| /* |
| * SuperH on-chip serial module support. (SCI with no FIFO / with FIFO) |
| * |
| * Copyright (C) 2002 - 2011 Paul Mundt |
| * Copyright (C) 2015 Glider bvba |
| * Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007). |
| * |
| * based off of the old drivers/char/sh-sci.c by: |
| * |
| * Copyright (C) 1999, 2000 Niibe Yutaka |
| * Copyright (C) 2000 Sugioka Toshinobu |
| * Modified to support multiple serial ports. Stuart Menefy (May 2000). |
| * Modified to support SecureEdge. David McCullough (2002) |
| * Modified to support SH7300 SCIF. Takashi Kusuda (Jun 2003). |
| * Removed SH7300 support (Jul 2007). |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) |
| #define SUPPORT_SYSRQ |
| #endif |
| |
| #undef DEBUG |
| |
| #include <linux/clk.h> |
| #include <linux/console.h> |
| #include <linux/ctype.h> |
| #include <linux/cpufreq.h> |
| #include <linux/delay.h> |
| #include <linux/dmaengine.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/err.h> |
| #include <linux/errno.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/ioport.h> |
| #include <linux/major.h> |
| #include <linux/module.h> |
| #include <linux/mm.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/scatterlist.h> |
| #include <linux/serial.h> |
| #include <linux/serial_sci.h> |
| #include <linux/sh_dma.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/sysrq.h> |
| #include <linux/timer.h> |
| #include <linux/tty.h> |
| #include <linux/tty_flip.h> |
| |
| #ifdef CONFIG_SUPERH |
| #include <asm/sh_bios.h> |
| #endif |
| |
| #include "serial_mctrl_gpio.h" |
| #include "sh-sci.h" |
| |
| /* Offsets into the sci_port->irqs array */ |
| enum { |
| SCIx_ERI_IRQ, |
| SCIx_RXI_IRQ, |
| SCIx_TXI_IRQ, |
| SCIx_BRI_IRQ, |
| SCIx_NR_IRQS, |
| |
| SCIx_MUX_IRQ = SCIx_NR_IRQS, /* special case */ |
| }; |
| |
| #define SCIx_IRQ_IS_MUXED(port) \ |
| ((port)->irqs[SCIx_ERI_IRQ] == \ |
| (port)->irqs[SCIx_RXI_IRQ]) || \ |
| ((port)->irqs[SCIx_ERI_IRQ] && \ |
| ((port)->irqs[SCIx_RXI_IRQ] < 0)) |
| |
| enum SCI_CLKS { |
| SCI_FCK, /* Functional Clock */ |
| SCI_SCK, /* Optional External Clock */ |
| SCI_BRG_INT, /* Optional BRG Internal Clock Source */ |
| SCI_SCIF_CLK, /* Optional BRG External Clock Source */ |
| SCI_NUM_CLKS |
| }; |
| |
| /* Bit x set means sampling rate x + 1 is supported */ |
| #define SCI_SR(x) BIT((x) - 1) |
| #define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1) |
| |
| #define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \ |
| SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \ |
| SCI_SR(19) | SCI_SR(27) |
| |
| #define min_sr(_port) ffs((_port)->sampling_rate_mask) |
| #define max_sr(_port) fls((_port)->sampling_rate_mask) |
| |
| /* Iterate over all supported sampling rates, from high to low */ |
| #define for_each_sr(_sr, _port) \ |
| for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \ |
| if ((_port)->sampling_rate_mask & SCI_SR((_sr))) |
| |
| struct sci_port { |
| struct uart_port port; |
| |
| /* Platform configuration */ |
| struct plat_sci_port *cfg; |
| unsigned int overrun_reg; |
| unsigned int overrun_mask; |
| unsigned int error_mask; |
| unsigned int error_clear; |
| unsigned int sampling_rate_mask; |
| resource_size_t reg_size; |
| struct mctrl_gpios *gpios; |
| |
| /* Break timer */ |
| struct timer_list break_timer; |
| int break_flag; |
| |
| /* Clocks */ |
| struct clk *clks[SCI_NUM_CLKS]; |
| unsigned long clk_rates[SCI_NUM_CLKS]; |
| |
| int irqs[SCIx_NR_IRQS]; |
| char *irqstr[SCIx_NR_IRQS]; |
| |
| struct dma_chan *chan_tx; |
| struct dma_chan *chan_rx; |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| dma_cookie_t cookie_tx; |
| dma_cookie_t cookie_rx[2]; |
| dma_cookie_t active_rx; |
| dma_addr_t tx_dma_addr; |
| unsigned int tx_dma_len; |
| struct scatterlist sg_rx[2]; |
| void *rx_buf[2]; |
| size_t buf_len_rx; |
| struct work_struct work_tx; |
| struct timer_list rx_timer; |
| unsigned int rx_timeout; |
| #endif |
| |
| bool autorts; |
| }; |
| |
| #define SCI_NPORTS CONFIG_SERIAL_SH_SCI_NR_UARTS |
| |
| static struct sci_port sci_ports[SCI_NPORTS]; |
| static struct uart_driver sci_uart_driver; |
| |
| static inline struct sci_port * |
| to_sci_port(struct uart_port *uart) |
| { |
| return container_of(uart, struct sci_port, port); |
| } |
| |
| struct plat_sci_reg { |
| u8 offset, size; |
| }; |
| |
| /* Helper for invalidating specific entries of an inherited map. */ |
| #define sci_reg_invalid { .offset = 0, .size = 0 } |
| |
| static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = { |
| [SCIx_PROBE_REGTYPE] = { |
| [0 ... SCIx_NR_REGS - 1] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SCI definitions, dependent on the port's regshift |
| * value. |
| */ |
| [SCIx_SCI_REGTYPE] = { |
| [SCSMR] = { 0x00, 8 }, |
| [SCBRR] = { 0x01, 8 }, |
| [SCSCR] = { 0x02, 8 }, |
| [SCxTDR] = { 0x03, 8 }, |
| [SCxSR] = { 0x04, 8 }, |
| [SCxRDR] = { 0x05, 8 }, |
| [SCFCR] = sci_reg_invalid, |
| [SCFDR] = sci_reg_invalid, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common definitions for legacy IrDA ports, dependent on |
| * regshift value. |
| */ |
| [SCIx_IRDA_REGTYPE] = { |
| [SCSMR] = { 0x00, 8 }, |
| [SCBRR] = { 0x01, 8 }, |
| [SCSCR] = { 0x02, 8 }, |
| [SCxTDR] = { 0x03, 8 }, |
| [SCxSR] = { 0x04, 8 }, |
| [SCxRDR] = { 0x05, 8 }, |
| [SCFCR] = { 0x06, 8 }, |
| [SCFDR] = { 0x07, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SCIFA definitions. |
| */ |
| [SCIx_SCIFA_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x20, 8 }, |
| [SCxSR] = { 0x14, 16 }, |
| [SCxRDR] = { 0x24, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = { 0x30, 16 }, |
| [SCPDR] = { 0x34, 16 }, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SCIFB definitions. |
| */ |
| [SCIx_SCIFB_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x40, 8 }, |
| [SCxSR] = { 0x14, 16 }, |
| [SCxRDR] = { 0x60, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = sci_reg_invalid, |
| [SCTFDR] = { 0x38, 16 }, |
| [SCRFDR] = { 0x3c, 16 }, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = { 0x30, 16 }, |
| [SCPDR] = { 0x34, 16 }, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SH-2(A) SCIF definitions for ports with FIFO data |
| * count registers. |
| */ |
| [SCIx_SH2_SCIF_FIFODATA_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = { 0x20, 16 }, |
| [SCLSR] = { 0x24, 16 }, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SH-3 SCIF definitions. |
| */ |
| [SCIx_SH3_SCIF_REGTYPE] = { |
| [SCSMR] = { 0x00, 8 }, |
| [SCBRR] = { 0x02, 8 }, |
| [SCSCR] = { 0x04, 8 }, |
| [SCxTDR] = { 0x06, 8 }, |
| [SCxSR] = { 0x08, 16 }, |
| [SCxRDR] = { 0x0a, 8 }, |
| [SCFCR] = { 0x0c, 8 }, |
| [SCFDR] = { 0x0e, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SH-4(A) SCIF(B) definitions. |
| */ |
| [SCIx_SH4_SCIF_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = { 0x20, 16 }, |
| [SCLSR] = { 0x24, 16 }, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SCIF definitions for ports with a Baud Rate Generator for |
| * External Clock (BRG). |
| */ |
| [SCIx_SH4_SCIF_BRG_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = { 0x20, 16 }, |
| [SCLSR] = { 0x24, 16 }, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = { 0x30, 16 }, |
| [SCCKS] = { 0x34, 16 }, |
| }, |
| |
| /* |
| * Common HSCIF definitions. |
| */ |
| [SCIx_HSCIF_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = { 0x20, 16 }, |
| [SCLSR] = { 0x24, 16 }, |
| [HSSRR] = { 0x40, 16 }, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = { 0x30, 16 }, |
| [SCCKS] = { 0x34, 16 }, |
| }, |
| |
| /* |
| * Common SH-4(A) SCIF(B) definitions for ports without an SCSPTR |
| * register. |
| */ |
| [SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = { 0x24, 16 }, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * Common SH-4(A) SCIF(B) definitions for ports with FIFO data |
| * count registers. |
| */ |
| [SCIx_SH4_SCIF_FIFODATA_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x0c, 8 }, |
| [SCxSR] = { 0x10, 16 }, |
| [SCxRDR] = { 0x14, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = { 0x1c, 16 }, /* aliased to SCFDR */ |
| [SCRFDR] = { 0x20, 16 }, |
| [SCSPTR] = { 0x24, 16 }, |
| [SCLSR] = { 0x28, 16 }, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| |
| /* |
| * SH7705-style SCIF(B) ports, lacking both SCSPTR and SCLSR |
| * registers. |
| */ |
| [SCIx_SH7705_SCIF_REGTYPE] = { |
| [SCSMR] = { 0x00, 16 }, |
| [SCBRR] = { 0x04, 8 }, |
| [SCSCR] = { 0x08, 16 }, |
| [SCxTDR] = { 0x20, 8 }, |
| [SCxSR] = { 0x14, 16 }, |
| [SCxRDR] = { 0x24, 8 }, |
| [SCFCR] = { 0x18, 16 }, |
| [SCFDR] = { 0x1c, 16 }, |
| [SCTFDR] = sci_reg_invalid, |
| [SCRFDR] = sci_reg_invalid, |
| [SCSPTR] = sci_reg_invalid, |
| [SCLSR] = sci_reg_invalid, |
| [HSSRR] = sci_reg_invalid, |
| [SCPCR] = sci_reg_invalid, |
| [SCPDR] = sci_reg_invalid, |
| [SCDL] = sci_reg_invalid, |
| [SCCKS] = sci_reg_invalid, |
| }, |
| }; |
| |
| #define sci_getreg(up, offset) (sci_regmap[to_sci_port(up)->cfg->regtype] + offset) |
| |
| /* |
| * The "offset" here is rather misleading, in that it refers to an enum |
| * value relative to the port mapping rather than the fixed offset |
| * itself, which needs to be manually retrieved from the platform's |
| * register map for the given port. |
| */ |
| static unsigned int sci_serial_in(struct uart_port *p, int offset) |
| { |
| const struct plat_sci_reg *reg = sci_getreg(p, offset); |
| |
| if (reg->size == 8) |
| return ioread8(p->membase + (reg->offset << p->regshift)); |
| else if (reg->size == 16) |
| return ioread16(p->membase + (reg->offset << p->regshift)); |
| else |
| WARN(1, "Invalid register access\n"); |
| |
| return 0; |
| } |
| |
| static void sci_serial_out(struct uart_port *p, int offset, int value) |
| { |
| const struct plat_sci_reg *reg = sci_getreg(p, offset); |
| |
| if (reg->size == 8) |
| iowrite8(value, p->membase + (reg->offset << p->regshift)); |
| else if (reg->size == 16) |
| iowrite16(value, p->membase + (reg->offset << p->regshift)); |
| else |
| WARN(1, "Invalid register access\n"); |
| } |
| |
| static int sci_probe_regmap(struct plat_sci_port *cfg) |
| { |
| switch (cfg->type) { |
| case PORT_SCI: |
| cfg->regtype = SCIx_SCI_REGTYPE; |
| break; |
| case PORT_IRDA: |
| cfg->regtype = SCIx_IRDA_REGTYPE; |
| break; |
| case PORT_SCIFA: |
| cfg->regtype = SCIx_SCIFA_REGTYPE; |
| break; |
| case PORT_SCIFB: |
| cfg->regtype = SCIx_SCIFB_REGTYPE; |
| break; |
| case PORT_SCIF: |
| /* |
| * The SH-4 is a bit of a misnomer here, although that's |
| * where this particular port layout originated. This |
| * configuration (or some slight variation thereof) |
| * remains the dominant model for all SCIFs. |
| */ |
| cfg->regtype = SCIx_SH4_SCIF_REGTYPE; |
| break; |
| case PORT_HSCIF: |
| cfg->regtype = SCIx_HSCIF_REGTYPE; |
| break; |
| default: |
| pr_err("Can't probe register map for given port\n"); |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static void sci_port_enable(struct sci_port *sci_port) |
| { |
| unsigned int i; |
| |
| if (!sci_port->port.dev) |
| return; |
| |
| pm_runtime_get_sync(sci_port->port.dev); |
| |
| for (i = 0; i < SCI_NUM_CLKS; i++) { |
| clk_prepare_enable(sci_port->clks[i]); |
| sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]); |
| } |
| sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK]; |
| } |
| |
| static void sci_port_disable(struct sci_port *sci_port) |
| { |
| unsigned int i; |
| |
| if (!sci_port->port.dev) |
| return; |
| |
| /* Cancel the break timer to ensure that the timer handler will not try |
| * to access the hardware with clocks and power disabled. Reset the |
| * break flag to make the break debouncing state machine ready for the |
| * next break. |
| */ |
| del_timer_sync(&sci_port->break_timer); |
| sci_port->break_flag = 0; |
| |
| for (i = SCI_NUM_CLKS; i-- > 0; ) |
| clk_disable_unprepare(sci_port->clks[i]); |
| |
| pm_runtime_put_sync(sci_port->port.dev); |
| } |
| |
| static inline unsigned long port_rx_irq_mask(struct uart_port *port) |
| { |
| /* |
| * Not all ports (such as SCIFA) will support REIE. Rather than |
| * special-casing the port type, we check the port initialization |
| * IRQ enable mask to see whether the IRQ is desired at all. If |
| * it's unset, it's logically inferred that there's no point in |
| * testing for it. |
| */ |
| return SCSCR_RIE | (to_sci_port(port)->cfg->scscr & SCSCR_REIE); |
| } |
| |
| static void sci_start_tx(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| unsigned short ctrl; |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| u16 new, scr = serial_port_in(port, SCSCR); |
| if (s->chan_tx) |
| new = scr | SCSCR_TDRQE; |
| else |
| new = scr & ~SCSCR_TDRQE; |
| if (new != scr) |
| serial_port_out(port, SCSCR, new); |
| } |
| |
| if (s->chan_tx && !uart_circ_empty(&s->port.state->xmit) && |
| dma_submit_error(s->cookie_tx)) { |
| s->cookie_tx = 0; |
| schedule_work(&s->work_tx); |
| } |
| #endif |
| |
| if (!s->chan_tx || port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| /* Set TIE (Transmit Interrupt Enable) bit in SCSCR */ |
| ctrl = serial_port_in(port, SCSCR); |
| serial_port_out(port, SCSCR, ctrl | SCSCR_TIE); |
| } |
| } |
| |
| static void sci_stop_tx(struct uart_port *port) |
| { |
| unsigned short ctrl; |
| |
| /* Clear TIE (Transmit Interrupt Enable) bit in SCSCR */ |
| ctrl = serial_port_in(port, SCSCR); |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| ctrl &= ~SCSCR_TDRQE; |
| |
| ctrl &= ~SCSCR_TIE; |
| |
| serial_port_out(port, SCSCR, ctrl); |
| } |
| |
| static void sci_start_rx(struct uart_port *port) |
| { |
| unsigned short ctrl; |
| |
| ctrl = serial_port_in(port, SCSCR) | port_rx_irq_mask(port); |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| ctrl &= ~SCSCR_RDRQE; |
| |
| serial_port_out(port, SCSCR, ctrl); |
| } |
| |
| static void sci_stop_rx(struct uart_port *port) |
| { |
| unsigned short ctrl; |
| |
| ctrl = serial_port_in(port, SCSCR); |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| ctrl &= ~SCSCR_RDRQE; |
| |
| ctrl &= ~port_rx_irq_mask(port); |
| |
| serial_port_out(port, SCSCR, ctrl); |
| } |
| |
| static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask) |
| { |
| if (port->type == PORT_SCI) { |
| /* Just store the mask */ |
| serial_port_out(port, SCxSR, mask); |
| } else if (to_sci_port(port)->overrun_mask == SCIFA_ORER) { |
| /* SCIFA/SCIFB and SCIF on SH7705/SH7720/SH7721 */ |
| /* Only clear the status bits we want to clear */ |
| serial_port_out(port, SCxSR, |
| serial_port_in(port, SCxSR) & mask); |
| } else { |
| /* Store the mask, clear parity/framing errors */ |
| serial_port_out(port, SCxSR, mask & ~(SCIF_FERC | SCIF_PERC)); |
| } |
| } |
| |
| #if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \ |
| defined(CONFIG_SERIAL_SH_SCI_EARLYCON) |
| |
| #ifdef CONFIG_CONSOLE_POLL |
| static int sci_poll_get_char(struct uart_port *port) |
| { |
| unsigned short status; |
| int c; |
| |
| do { |
| status = serial_port_in(port, SCxSR); |
| if (status & SCxSR_ERRORS(port)) { |
| sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port)); |
| continue; |
| } |
| break; |
| } while (1); |
| |
| if (!(status & SCxSR_RDxF(port))) |
| return NO_POLL_CHAR; |
| |
| c = serial_port_in(port, SCxRDR); |
| |
| /* Dummy read */ |
| serial_port_in(port, SCxSR); |
| sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port)); |
| |
| return c; |
| } |
| #endif |
| |
| static void sci_poll_put_char(struct uart_port *port, unsigned char c) |
| { |
| unsigned short status; |
| |
| do { |
| status = serial_port_in(port, SCxSR); |
| } while (!(status & SCxSR_TDxE(port))); |
| |
| serial_port_out(port, SCxTDR, c); |
| sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port)); |
| } |
| #endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE || |
| CONFIG_SERIAL_SH_SCI_EARLYCON */ |
| |
| static void sci_init_pins(struct uart_port *port, unsigned int cflag) |
| { |
| struct sci_port *s = to_sci_port(port); |
| |
| /* |
| * Use port-specific handler if provided. |
| */ |
| if (s->cfg->ops && s->cfg->ops->init_pins) { |
| s->cfg->ops->init_pins(port, cflag); |
| return; |
| } |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| u16 ctrl = serial_port_in(port, SCPCR); |
| |
| /* Enable RXD and TXD pin functions */ |
| ctrl &= ~(SCPCR_RXDC | SCPCR_TXDC); |
| if (to_sci_port(port)->cfg->capabilities & SCIx_HAVE_RTSCTS) { |
| /* RTS# is output, driven 1 */ |
| ctrl |= SCPCR_RTSC; |
| serial_port_out(port, SCPDR, |
| serial_port_in(port, SCPDR) | SCPDR_RTSD); |
| /* Enable CTS# pin function */ |
| ctrl &= ~SCPCR_CTSC; |
| } |
| serial_port_out(port, SCPCR, ctrl); |
| } else if (sci_getreg(port, SCSPTR)->size) { |
| u16 status = serial_port_in(port, SCSPTR); |
| |
| /* RTS# is output, driven 1 */ |
| status |= SCSPTR_RTSIO | SCSPTR_RTSDT; |
| /* CTS# and SCK are inputs */ |
| status &= ~(SCSPTR_CTSIO | SCSPTR_SCKIO); |
| serial_port_out(port, SCSPTR, status); |
| } |
| } |
| |
| static int sci_txfill(struct uart_port *port) |
| { |
| const struct plat_sci_reg *reg; |
| |
| reg = sci_getreg(port, SCTFDR); |
| if (reg->size) |
| return serial_port_in(port, SCTFDR) & ((port->fifosize << 1) - 1); |
| |
| reg = sci_getreg(port, SCFDR); |
| if (reg->size) |
| return serial_port_in(port, SCFDR) >> 8; |
| |
| return !(serial_port_in(port, SCxSR) & SCI_TDRE); |
| } |
| |
| static int sci_txroom(struct uart_port *port) |
| { |
| return port->fifosize - sci_txfill(port); |
| } |
| |
| static int sci_rxfill(struct uart_port *port) |
| { |
| const struct plat_sci_reg *reg; |
| |
| reg = sci_getreg(port, SCRFDR); |
| if (reg->size) |
| return serial_port_in(port, SCRFDR) & ((port->fifosize << 1) - 1); |
| |
| reg = sci_getreg(port, SCFDR); |
| if (reg->size) |
| return serial_port_in(port, SCFDR) & ((port->fifosize << 1) - 1); |
| |
| return (serial_port_in(port, SCxSR) & SCxSR_RDxF(port)) != 0; |
| } |
| |
| /* |
| * SCI helper for checking the state of the muxed port/RXD pins. |
| */ |
| static inline int sci_rxd_in(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| |
| if (s->cfg->port_reg <= 0) |
| return 1; |
| |
| /* Cast for ARM damage */ |
| return !!__raw_readb((void __iomem *)(uintptr_t)s->cfg->port_reg); |
| } |
| |
| /* ********************************************************************** * |
| * the interrupt related routines * |
| * ********************************************************************** */ |
| |
| static void sci_transmit_chars(struct uart_port *port) |
| { |
| struct circ_buf *xmit = &port->state->xmit; |
| unsigned int stopped = uart_tx_stopped(port); |
| unsigned short status; |
| unsigned short ctrl; |
| int count; |
| |
| status = serial_port_in(port, SCxSR); |
| if (!(status & SCxSR_TDxE(port))) { |
| ctrl = serial_port_in(port, SCSCR); |
| if (uart_circ_empty(xmit)) |
| ctrl &= ~SCSCR_TIE; |
| else |
| ctrl |= SCSCR_TIE; |
| serial_port_out(port, SCSCR, ctrl); |
| return; |
| } |
| |
| count = sci_txroom(port); |
| |
| do { |
| unsigned char c; |
| |
| if (port->x_char) { |
| c = port->x_char; |
| port->x_char = 0; |
| } else if (!uart_circ_empty(xmit) && !stopped) { |
| c = xmit->buf[xmit->tail]; |
| xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); |
| } else { |
| break; |
| } |
| |
| serial_port_out(port, SCxTDR, c); |
| |
| port->icount.tx++; |
| } while (--count > 0); |
| |
| sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port)); |
| |
| if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| uart_write_wakeup(port); |
| if (uart_circ_empty(xmit)) { |
| sci_stop_tx(port); |
| } else { |
| ctrl = serial_port_in(port, SCSCR); |
| |
| if (port->type != PORT_SCI) { |
| serial_port_in(port, SCxSR); /* Dummy read */ |
| sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port)); |
| } |
| |
| ctrl |= SCSCR_TIE; |
| serial_port_out(port, SCSCR, ctrl); |
| } |
| } |
| |
| /* On SH3, SCIF may read end-of-break as a space->mark char */ |
| #define STEPFN(c) ({int __c = (c); (((__c-1)|(__c)) == -1); }) |
| |
| static void sci_receive_chars(struct uart_port *port) |
| { |
| struct sci_port *sci_port = to_sci_port(port); |
| struct tty_port *tport = &port->state->port; |
| int i, count, copied = 0; |
| unsigned short status; |
| unsigned char flag; |
| |
| status = serial_port_in(port, SCxSR); |
| if (!(status & SCxSR_RDxF(port))) |
| return; |
| |
| while (1) { |
| /* Don't copy more bytes than there is room for in the buffer */ |
| count = tty_buffer_request_room(tport, sci_rxfill(port)); |
| |
| /* If for any reason we can't copy more data, we're done! */ |
| if (count == 0) |
| break; |
| |
| if (port->type == PORT_SCI) { |
| char c = serial_port_in(port, SCxRDR); |
| if (uart_handle_sysrq_char(port, c) || |
| sci_port->break_flag) |
| count = 0; |
| else |
| tty_insert_flip_char(tport, c, TTY_NORMAL); |
| } else { |
| for (i = 0; i < count; i++) { |
| char c = serial_port_in(port, SCxRDR); |
| |
| status = serial_port_in(port, SCxSR); |
| #if defined(CONFIG_CPU_SH3) |
| /* Skip "chars" during break */ |
| if (sci_port->break_flag) { |
| if ((c == 0) && |
| (status & SCxSR_FER(port))) { |
| count--; i--; |
| continue; |
| } |
| |
| /* Nonzero => end-of-break */ |
| dev_dbg(port->dev, "debounce<%02x>\n", c); |
| sci_port->break_flag = 0; |
| |
| if (STEPFN(c)) { |
| count--; i--; |
| continue; |
| } |
| } |
| #endif /* CONFIG_CPU_SH3 */ |
| if (uart_handle_sysrq_char(port, c)) { |
| count--; i--; |
| continue; |
| } |
| |
| /* Store data and status */ |
| if (status & SCxSR_FER(port)) { |
| flag = TTY_FRAME; |
| port->icount.frame++; |
| dev_notice(port->dev, "frame error\n"); |
| } else if (status & SCxSR_PER(port)) { |
| flag = TTY_PARITY; |
| port->icount.parity++; |
| dev_notice(port->dev, "parity error\n"); |
| } else |
| flag = TTY_NORMAL; |
| |
| tty_insert_flip_char(tport, c, flag); |
| } |
| } |
| |
| serial_port_in(port, SCxSR); /* dummy read */ |
| sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port)); |
| |
| copied += count; |
| port->icount.rx += count; |
| } |
| |
| if (copied) { |
| /* Tell the rest of the system the news. New characters! */ |
| tty_flip_buffer_push(tport); |
| } else { |
| serial_port_in(port, SCxSR); /* dummy read */ |
| sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port)); |
| } |
| } |
| |
| #define SCI_BREAK_JIFFIES (HZ/20) |
| |
| /* |
| * The sci generates interrupts during the break, |
| * 1 per millisecond or so during the break period, for 9600 baud. |
| * So dont bother disabling interrupts. |
| * But dont want more than 1 break event. |
| * Use a kernel timer to periodically poll the rx line until |
| * the break is finished. |
| */ |
| static inline void sci_schedule_break_timer(struct sci_port *port) |
| { |
| mod_timer(&port->break_timer, jiffies + SCI_BREAK_JIFFIES); |
| } |
| |
| /* Ensure that two consecutive samples find the break over. */ |
| static void sci_break_timer(unsigned long data) |
| { |
| struct sci_port *port = (struct sci_port *)data; |
| |
| if (sci_rxd_in(&port->port) == 0) { |
| port->break_flag = 1; |
| sci_schedule_break_timer(port); |
| } else if (port->break_flag == 1) { |
| /* break is over. */ |
| port->break_flag = 2; |
| sci_schedule_break_timer(port); |
| } else |
| port->break_flag = 0; |
| } |
| |
| static int sci_handle_errors(struct uart_port *port) |
| { |
| int copied = 0; |
| unsigned short status = serial_port_in(port, SCxSR); |
| struct tty_port *tport = &port->state->port; |
| struct sci_port *s = to_sci_port(port); |
| |
| /* Handle overruns */ |
| if (status & s->overrun_mask) { |
| port->icount.overrun++; |
| |
| /* overrun error */ |
| if (tty_insert_flip_char(tport, 0, TTY_OVERRUN)) |
| copied++; |
| |
| dev_notice(port->dev, "overrun error\n"); |
| } |
| |
| if (status & SCxSR_FER(port)) { |
| if (sci_rxd_in(port) == 0) { |
| /* Notify of BREAK */ |
| struct sci_port *sci_port = to_sci_port(port); |
| |
| if (!sci_port->break_flag) { |
| port->icount.brk++; |
| |
| sci_port->break_flag = 1; |
| sci_schedule_break_timer(sci_port); |
| |
| /* Do sysrq handling. */ |
| if (uart_handle_break(port)) |
| return 0; |
| |
| dev_dbg(port->dev, "BREAK detected\n"); |
| |
| if (tty_insert_flip_char(tport, 0, TTY_BREAK)) |
| copied++; |
| } |
| |
| } else { |
| /* frame error */ |
| port->icount.frame++; |
| |
| if (tty_insert_flip_char(tport, 0, TTY_FRAME)) |
| copied++; |
| |
| dev_notice(port->dev, "frame error\n"); |
| } |
| } |
| |
| if (status & SCxSR_PER(port)) { |
| /* parity error */ |
| port->icount.parity++; |
| |
| if (tty_insert_flip_char(tport, 0, TTY_PARITY)) |
| copied++; |
| |
| dev_notice(port->dev, "parity error\n"); |
| } |
| |
| if (copied) |
| tty_flip_buffer_push(tport); |
| |
| return copied; |
| } |
| |
| static int sci_handle_fifo_overrun(struct uart_port *port) |
| { |
| struct tty_port *tport = &port->state->port; |
| struct sci_port *s = to_sci_port(port); |
| const struct plat_sci_reg *reg; |
| int copied = 0; |
| u16 status; |
| |
| reg = sci_getreg(port, s->overrun_reg); |
| if (!reg->size) |
| return 0; |
| |
| status = serial_port_in(port, s->overrun_reg); |
| if (status & s->overrun_mask) { |
| status &= ~s->overrun_mask; |
| serial_port_out(port, s->overrun_reg, status); |
| |
| port->icount.overrun++; |
| |
| tty_insert_flip_char(tport, 0, TTY_OVERRUN); |
| tty_flip_buffer_push(tport); |
| |
| dev_dbg(port->dev, "overrun error\n"); |
| copied++; |
| } |
| |
| return copied; |
| } |
| |
| static int sci_handle_breaks(struct uart_port *port) |
| { |
| int copied = 0; |
| unsigned short status = serial_port_in(port, SCxSR); |
| struct tty_port *tport = &port->state->port; |
| struct sci_port *s = to_sci_port(port); |
| |
| if (uart_handle_break(port)) |
| return 0; |
| |
| if (!s->break_flag && status & SCxSR_BRK(port)) { |
| #if defined(CONFIG_CPU_SH3) |
| /* Debounce break */ |
| s->break_flag = 1; |
| #endif |
| |
| port->icount.brk++; |
| |
| /* Notify of BREAK */ |
| if (tty_insert_flip_char(tport, 0, TTY_BREAK)) |
| copied++; |
| |
| dev_dbg(port->dev, "BREAK detected\n"); |
| } |
| |
| if (copied) |
| tty_flip_buffer_push(tport); |
| |
| copied += sci_handle_fifo_overrun(port); |
| |
| return copied; |
| } |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| static void sci_dma_tx_complete(void *arg) |
| { |
| struct sci_port *s = arg; |
| struct uart_port *port = &s->port; |
| struct circ_buf *xmit = &port->state->xmit; |
| unsigned long flags; |
| |
| dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| |
| xmit->tail += s->tx_dma_len; |
| xmit->tail &= UART_XMIT_SIZE - 1; |
| |
| port->icount.tx += s->tx_dma_len; |
| |
| if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) |
| uart_write_wakeup(port); |
| |
| if (!uart_circ_empty(xmit)) { |
| s->cookie_tx = 0; |
| schedule_work(&s->work_tx); |
| } else { |
| s->cookie_tx = -EINVAL; |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| u16 ctrl = serial_port_in(port, SCSCR); |
| serial_port_out(port, SCSCR, ctrl & ~SCSCR_TIE); |
| } |
| } |
| |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| /* Locking: called with port lock held */ |
| static int sci_dma_rx_push(struct sci_port *s, void *buf, size_t count) |
| { |
| struct uart_port *port = &s->port; |
| struct tty_port *tport = &port->state->port; |
| int copied; |
| |
| copied = tty_insert_flip_string(tport, buf, count); |
| if (copied < count) { |
| dev_warn(port->dev, "Rx overrun: dropping %zu bytes\n", |
| count - copied); |
| port->icount.buf_overrun++; |
| } |
| |
| port->icount.rx += copied; |
| |
| return copied; |
| } |
| |
| static int sci_dma_rx_find_active(struct sci_port *s) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < ARRAY_SIZE(s->cookie_rx); i++) |
| if (s->active_rx == s->cookie_rx[i]) |
| return i; |
| |
| dev_err(s->port.dev, "%s: Rx cookie %d not found!\n", __func__, |
| s->active_rx); |
| return -1; |
| } |
| |
| static void sci_rx_dma_release(struct sci_port *s, bool enable_pio) |
| { |
| struct dma_chan *chan = s->chan_rx; |
| struct uart_port *port = &s->port; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| s->chan_rx = NULL; |
| s->cookie_rx[0] = s->cookie_rx[1] = -EINVAL; |
| spin_unlock_irqrestore(&port->lock, flags); |
| dmaengine_terminate_all(chan); |
| dma_free_coherent(chan->device->dev, s->buf_len_rx * 2, s->rx_buf[0], |
| sg_dma_address(&s->sg_rx[0])); |
| dma_release_channel(chan); |
| if (enable_pio) |
| sci_start_rx(port); |
| } |
| |
| static void sci_dma_rx_complete(void *arg) |
| { |
| struct sci_port *s = arg; |
| struct dma_chan *chan = s->chan_rx; |
| struct uart_port *port = &s->port; |
| struct dma_async_tx_descriptor *desc; |
| unsigned long flags; |
| int active, count = 0; |
| |
| dev_dbg(port->dev, "%s(%d) active cookie %d\n", __func__, port->line, |
| s->active_rx); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| |
| active = sci_dma_rx_find_active(s); |
| if (active >= 0) |
| count = sci_dma_rx_push(s, s->rx_buf[active], s->buf_len_rx); |
| |
| mod_timer(&s->rx_timer, jiffies + s->rx_timeout); |
| |
| if (count) |
| tty_flip_buffer_push(&port->state->port); |
| |
| desc = dmaengine_prep_slave_sg(s->chan_rx, &s->sg_rx[active], 1, |
| DMA_DEV_TO_MEM, |
| DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| if (!desc) |
| goto fail; |
| |
| desc->callback = sci_dma_rx_complete; |
| desc->callback_param = s; |
| s->cookie_rx[active] = dmaengine_submit(desc); |
| if (dma_submit_error(s->cookie_rx[active])) |
| goto fail; |
| |
| s->active_rx = s->cookie_rx[!active]; |
| |
| dma_async_issue_pending(chan); |
| |
| dev_dbg(port->dev, "%s: cookie %d #%d, new active cookie %d\n", |
| __func__, s->cookie_rx[active], active, s->active_rx); |
| spin_unlock_irqrestore(&port->lock, flags); |
| return; |
| |
| fail: |
| spin_unlock_irqrestore(&port->lock, flags); |
| dev_warn(port->dev, "Failed submitting Rx DMA descriptor\n"); |
| sci_rx_dma_release(s, true); |
| } |
| |
| static void sci_tx_dma_release(struct sci_port *s, bool enable_pio) |
| { |
| struct dma_chan *chan = s->chan_tx; |
| struct uart_port *port = &s->port; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| s->chan_tx = NULL; |
| s->cookie_tx = -EINVAL; |
| spin_unlock_irqrestore(&port->lock, flags); |
| dmaengine_terminate_all(chan); |
| dma_unmap_single(chan->device->dev, s->tx_dma_addr, UART_XMIT_SIZE, |
| DMA_TO_DEVICE); |
| dma_release_channel(chan); |
| if (enable_pio) |
| sci_start_tx(port); |
| } |
| |
| static void sci_submit_rx(struct sci_port *s) |
| { |
| struct dma_chan *chan = s->chan_rx; |
| int i; |
| |
| for (i = 0; i < 2; i++) { |
| struct scatterlist *sg = &s->sg_rx[i]; |
| struct dma_async_tx_descriptor *desc; |
| |
| desc = dmaengine_prep_slave_sg(chan, |
| sg, 1, DMA_DEV_TO_MEM, |
| DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| if (!desc) |
| goto fail; |
| |
| desc->callback = sci_dma_rx_complete; |
| desc->callback_param = s; |
| s->cookie_rx[i] = dmaengine_submit(desc); |
| if (dma_submit_error(s->cookie_rx[i])) |
| goto fail; |
| |
| dev_dbg(s->port.dev, "%s(): cookie %d to #%d\n", __func__, |
| s->cookie_rx[i], i); |
| } |
| |
| s->active_rx = s->cookie_rx[0]; |
| |
| dma_async_issue_pending(chan); |
| return; |
| |
| fail: |
| if (i) |
| dmaengine_terminate_all(chan); |
| for (i = 0; i < 2; i++) |
| s->cookie_rx[i] = -EINVAL; |
| s->active_rx = -EINVAL; |
| dev_warn(s->port.dev, "Failed to re-start Rx DMA, using PIO\n"); |
| sci_rx_dma_release(s, true); |
| } |
| |
| static void work_fn_tx(struct work_struct *work) |
| { |
| struct sci_port *s = container_of(work, struct sci_port, work_tx); |
| struct dma_async_tx_descriptor *desc; |
| struct dma_chan *chan = s->chan_tx; |
| struct uart_port *port = &s->port; |
| struct circ_buf *xmit = &port->state->xmit; |
| dma_addr_t buf; |
| |
| /* |
| * DMA is idle now. |
| * Port xmit buffer is already mapped, and it is one page... Just adjust |
| * offsets and lengths. Since it is a circular buffer, we have to |
| * transmit till the end, and then the rest. Take the port lock to get a |
| * consistent xmit buffer state. |
| */ |
| spin_lock_irq(&port->lock); |
| buf = s->tx_dma_addr + (xmit->tail & (UART_XMIT_SIZE - 1)); |
| s->tx_dma_len = min_t(unsigned int, |
| CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE), |
| CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE)); |
| spin_unlock_irq(&port->lock); |
| |
| desc = dmaengine_prep_slave_single(chan, buf, s->tx_dma_len, |
| DMA_MEM_TO_DEV, |
| DMA_PREP_INTERRUPT | DMA_CTRL_ACK); |
| if (!desc) { |
| dev_warn(port->dev, "Failed preparing Tx DMA descriptor\n"); |
| /* switch to PIO */ |
| sci_tx_dma_release(s, true); |
| return; |
| } |
| |
| dma_sync_single_for_device(chan->device->dev, buf, s->tx_dma_len, |
| DMA_TO_DEVICE); |
| |
| spin_lock_irq(&port->lock); |
| desc->callback = sci_dma_tx_complete; |
| desc->callback_param = s; |
| spin_unlock_irq(&port->lock); |
| s->cookie_tx = dmaengine_submit(desc); |
| if (dma_submit_error(s->cookie_tx)) { |
| dev_warn(port->dev, "Failed submitting Tx DMA descriptor\n"); |
| /* switch to PIO */ |
| sci_tx_dma_release(s, true); |
| return; |
| } |
| |
| dev_dbg(port->dev, "%s: %p: %d...%d, cookie %d\n", |
| __func__, xmit->buf, xmit->tail, xmit->head, s->cookie_tx); |
| |
| dma_async_issue_pending(chan); |
| } |
| |
| static void rx_timer_fn(unsigned long arg) |
| { |
| struct sci_port *s = (struct sci_port *)arg; |
| struct dma_chan *chan = s->chan_rx; |
| struct uart_port *port = &s->port; |
| struct dma_tx_state state; |
| enum dma_status status; |
| unsigned long flags; |
| unsigned int read; |
| int active, count; |
| u16 scr; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| |
| dev_dbg(port->dev, "DMA Rx timed out\n"); |
| |
| active = sci_dma_rx_find_active(s); |
| if (active < 0) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| return; |
| } |
| |
| status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state); |
| if (status == DMA_COMPLETE) { |
| dev_dbg(port->dev, "Cookie %d #%d has already completed\n", |
| s->active_rx, active); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| /* Let packet complete handler take care of the packet */ |
| return; |
| } |
| |
| dmaengine_pause(chan); |
| |
| /* |
| * sometimes DMA transfer doesn't stop even if it is stopped and |
| * data keeps on coming until transaction is complete so check |
| * for DMA_COMPLETE again |
| * Let packet complete handler take care of the packet |
| */ |
| status = dmaengine_tx_status(s->chan_rx, s->active_rx, &state); |
| if (status == DMA_COMPLETE) { |
| spin_unlock_irqrestore(&port->lock, flags); |
| dev_dbg(port->dev, "Transaction complete after DMA engine was stopped"); |
| return; |
| } |
| |
| /* Handle incomplete DMA receive */ |
| dmaengine_terminate_all(s->chan_rx); |
| read = sg_dma_len(&s->sg_rx[active]) - state.residue; |
| dev_dbg(port->dev, "Read %u bytes with cookie %d\n", read, |
| s->active_rx); |
| |
| if (read) { |
| count = sci_dma_rx_push(s, s->rx_buf[active], read); |
| if (count) |
| tty_flip_buffer_push(&port->state->port); |
| } |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| sci_submit_rx(s); |
| |
| /* Direct new serial port interrupts back to CPU */ |
| scr = serial_port_in(port, SCSCR); |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| scr &= ~SCSCR_RDRQE; |
| enable_irq(s->irqs[SCIx_RXI_IRQ]); |
| } |
| serial_port_out(port, SCSCR, scr | SCSCR_RIE); |
| |
| spin_unlock_irqrestore(&port->lock, flags); |
| } |
| |
| static struct dma_chan *sci_request_dma_chan(struct uart_port *port, |
| enum dma_transfer_direction dir, |
| unsigned int id) |
| { |
| dma_cap_mask_t mask; |
| struct dma_chan *chan; |
| struct dma_slave_config cfg; |
| int ret; |
| |
| dma_cap_zero(mask); |
| dma_cap_set(DMA_SLAVE, mask); |
| |
| chan = dma_request_slave_channel_compat(mask, shdma_chan_filter, |
| (void *)(unsigned long)id, port->dev, |
| dir == DMA_MEM_TO_DEV ? "tx" : "rx"); |
| if (!chan) { |
| dev_warn(port->dev, |
| "dma_request_slave_channel_compat failed\n"); |
| return NULL; |
| } |
| |
| memset(&cfg, 0, sizeof(cfg)); |
| cfg.direction = dir; |
| if (dir == DMA_MEM_TO_DEV) { |
| cfg.dst_addr = port->mapbase + |
| (sci_getreg(port, SCxTDR)->offset << port->regshift); |
| cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; |
| } else { |
| cfg.src_addr = port->mapbase + |
| (sci_getreg(port, SCxRDR)->offset << port->regshift); |
| cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; |
| } |
| |
| ret = dmaengine_slave_config(chan, &cfg); |
| if (ret) { |
| dev_warn(port->dev, "dmaengine_slave_config failed %d\n", ret); |
| dma_release_channel(chan); |
| return NULL; |
| } |
| |
| return chan; |
| } |
| |
| static void sci_request_dma(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| struct dma_chan *chan; |
| |
| dev_dbg(port->dev, "%s: port %d\n", __func__, port->line); |
| |
| if (!port->dev->of_node && |
| (s->cfg->dma_slave_tx <= 0 || s->cfg->dma_slave_rx <= 0)) |
| return; |
| |
| s->cookie_tx = -EINVAL; |
| chan = sci_request_dma_chan(port, DMA_MEM_TO_DEV, s->cfg->dma_slave_tx); |
| dev_dbg(port->dev, "%s: TX: got channel %p\n", __func__, chan); |
| if (chan) { |
| s->chan_tx = chan; |
| /* UART circular tx buffer is an aligned page. */ |
| s->tx_dma_addr = dma_map_single(chan->device->dev, |
| port->state->xmit.buf, |
| UART_XMIT_SIZE, |
| DMA_TO_DEVICE); |
| if (dma_mapping_error(chan->device->dev, s->tx_dma_addr)) { |
| dev_warn(port->dev, "Failed mapping Tx DMA descriptor\n"); |
| dma_release_channel(chan); |
| s->chan_tx = NULL; |
| } else { |
| dev_dbg(port->dev, "%s: mapped %lu@%p to %pad\n", |
| __func__, UART_XMIT_SIZE, |
| port->state->xmit.buf, &s->tx_dma_addr); |
| } |
| |
| INIT_WORK(&s->work_tx, work_fn_tx); |
| } |
| |
| chan = sci_request_dma_chan(port, DMA_DEV_TO_MEM, s->cfg->dma_slave_rx); |
| dev_dbg(port->dev, "%s: RX: got channel %p\n", __func__, chan); |
| if (chan) { |
| unsigned int i; |
| dma_addr_t dma; |
| void *buf; |
| |
| s->chan_rx = chan; |
| |
| s->buf_len_rx = 2 * max_t(size_t, 16, port->fifosize); |
| buf = dma_alloc_coherent(chan->device->dev, s->buf_len_rx * 2, |
| &dma, GFP_KERNEL); |
| if (!buf) { |
| dev_warn(port->dev, |
| "Failed to allocate Rx dma buffer, using PIO\n"); |
| dma_release_channel(chan); |
| s->chan_rx = NULL; |
| return; |
| } |
| |
| for (i = 0; i < 2; i++) { |
| struct scatterlist *sg = &s->sg_rx[i]; |
| |
| sg_init_table(sg, 1); |
| s->rx_buf[i] = buf; |
| sg_dma_address(sg) = dma; |
| sg_dma_len(sg) = s->buf_len_rx; |
| |
| buf += s->buf_len_rx; |
| dma += s->buf_len_rx; |
| } |
| |
| setup_timer(&s->rx_timer, rx_timer_fn, (unsigned long)s); |
| |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| sci_submit_rx(s); |
| } |
| } |
| |
| static void sci_free_dma(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| |
| if (s->chan_tx) |
| sci_tx_dma_release(s, false); |
| if (s->chan_rx) |
| sci_rx_dma_release(s, false); |
| } |
| #else |
| static inline void sci_request_dma(struct uart_port *port) |
| { |
| } |
| |
| static inline void sci_free_dma(struct uart_port *port) |
| { |
| } |
| #endif |
| |
| static irqreturn_t sci_rx_interrupt(int irq, void *ptr) |
| { |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| struct uart_port *port = ptr; |
| struct sci_port *s = to_sci_port(port); |
| |
| if (s->chan_rx) { |
| u16 scr = serial_port_in(port, SCSCR); |
| u16 ssr = serial_port_in(port, SCxSR); |
| |
| /* Disable future Rx interrupts */ |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| disable_irq_nosync(irq); |
| scr |= SCSCR_RDRQE; |
| } else { |
| scr &= ~SCSCR_RIE; |
| sci_submit_rx(s); |
| } |
| serial_port_out(port, SCSCR, scr); |
| /* Clear current interrupt */ |
| serial_port_out(port, SCxSR, |
| ssr & ~(SCIF_DR | SCxSR_RDxF(port))); |
| dev_dbg(port->dev, "Rx IRQ %lu: setup t-out in %u jiffies\n", |
| jiffies, s->rx_timeout); |
| mod_timer(&s->rx_timer, jiffies + s->rx_timeout); |
| |
| return IRQ_HANDLED; |
| } |
| #endif |
| |
| /* I think sci_receive_chars has to be called irrespective |
| * of whether the I_IXOFF is set, otherwise, how is the interrupt |
| * to be disabled? |
| */ |
| sci_receive_chars(ptr); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t sci_tx_interrupt(int irq, void *ptr) |
| { |
| struct uart_port *port = ptr; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&port->lock, flags); |
| sci_transmit_chars(port); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t sci_er_interrupt(int irq, void *ptr) |
| { |
| struct uart_port *port = ptr; |
| struct sci_port *s = to_sci_port(port); |
| |
| /* Handle errors */ |
| if (port->type == PORT_SCI) { |
| if (sci_handle_errors(port)) { |
| /* discard character in rx buffer */ |
| serial_port_in(port, SCxSR); |
| sci_clear_SCxSR(port, SCxSR_RDxF_CLEAR(port)); |
| } |
| } else { |
| sci_handle_fifo_overrun(port); |
| if (!s->chan_rx) |
| sci_receive_chars(ptr); |
| } |
| |
| sci_clear_SCxSR(port, SCxSR_ERROR_CLEAR(port)); |
| |
| /* Kick the transmission */ |
| if (!s->chan_tx) |
| sci_tx_interrupt(irq, ptr); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t sci_br_interrupt(int irq, void *ptr) |
| { |
| struct uart_port *port = ptr; |
| |
| /* Handle BREAKs */ |
| sci_handle_breaks(port); |
| sci_clear_SCxSR(port, SCxSR_BREAK_CLEAR(port)); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t sci_mpxed_interrupt(int irq, void *ptr) |
| { |
| unsigned short ssr_status, scr_status, err_enabled, orer_status = 0; |
| struct uart_port *port = ptr; |
| struct sci_port *s = to_sci_port(port); |
| irqreturn_t ret = IRQ_NONE; |
| |
| ssr_status = serial_port_in(port, SCxSR); |
| scr_status = serial_port_in(port, SCSCR); |
| if (s->overrun_reg == SCxSR) |
| orer_status = ssr_status; |
| else { |
| if (sci_getreg(port, s->overrun_reg)->size) |
| orer_status = serial_port_in(port, s->overrun_reg); |
| } |
| |
| err_enabled = scr_status & port_rx_irq_mask(port); |
| |
| /* Tx Interrupt */ |
| if ((ssr_status & SCxSR_TDxE(port)) && (scr_status & SCSCR_TIE) && |
| !s->chan_tx) |
| ret = sci_tx_interrupt(irq, ptr); |
| |
| /* |
| * Rx Interrupt: if we're using DMA, the DMA controller clears RDF / |
| * DR flags |
| */ |
| if (((ssr_status & SCxSR_RDxF(port)) || s->chan_rx) && |
| (scr_status & SCSCR_RIE)) |
| ret = sci_rx_interrupt(irq, ptr); |
| |
| /* Error Interrupt */ |
| if ((ssr_status & SCxSR_ERRORS(port)) && err_enabled) |
| ret = sci_er_interrupt(irq, ptr); |
| |
| /* Break Interrupt */ |
| if ((ssr_status & SCxSR_BRK(port)) && err_enabled) |
| ret = sci_br_interrupt(irq, ptr); |
| |
| /* Overrun Interrupt */ |
| if (orer_status & s->overrun_mask) { |
| sci_handle_fifo_overrun(port); |
| ret = IRQ_HANDLED; |
| } |
| |
| return ret; |
| } |
| |
| static const struct sci_irq_desc { |
| const char *desc; |
| irq_handler_t handler; |
| } sci_irq_desc[] = { |
| /* |
| * Split out handlers, the default case. |
| */ |
| [SCIx_ERI_IRQ] = { |
| .desc = "rx err", |
| .handler = sci_er_interrupt, |
| }, |
| |
| [SCIx_RXI_IRQ] = { |
| .desc = "rx full", |
| .handler = sci_rx_interrupt, |
| }, |
| |
| [SCIx_TXI_IRQ] = { |
| .desc = "tx empty", |
| .handler = sci_tx_interrupt, |
| }, |
| |
| [SCIx_BRI_IRQ] = { |
| .desc = "break", |
| .handler = sci_br_interrupt, |
| }, |
| |
| /* |
| * Special muxed handler. |
| */ |
| [SCIx_MUX_IRQ] = { |
| .desc = "mux", |
| .handler = sci_mpxed_interrupt, |
| }, |
| }; |
| |
| static int sci_request_irq(struct sci_port *port) |
| { |
| struct uart_port *up = &port->port; |
| int i, j, ret = 0; |
| |
| for (i = j = 0; i < SCIx_NR_IRQS; i++, j++) { |
| const struct sci_irq_desc *desc; |
| int irq; |
| |
| if (SCIx_IRQ_IS_MUXED(port)) { |
| i = SCIx_MUX_IRQ; |
| irq = up->irq; |
| } else { |
| irq = port->irqs[i]; |
| |
| /* |
| * Certain port types won't support all of the |
| * available interrupt sources. |
| */ |
| if (unlikely(irq < 0)) |
| continue; |
| } |
| |
| desc = sci_irq_desc + i; |
| port->irqstr[j] = kasprintf(GFP_KERNEL, "%s:%s", |
| dev_name(up->dev), desc->desc); |
| if (!port->irqstr[j]) |
| goto out_nomem; |
| |
| ret = request_irq(irq, desc->handler, up->irqflags, |
| port->irqstr[j], port); |
| if (unlikely(ret)) { |
| dev_err(up->dev, "Can't allocate %s IRQ\n", desc->desc); |
| goto out_noirq; |
| } |
| } |
| |
| return 0; |
| |
| out_noirq: |
| while (--i >= 0) |
| free_irq(port->irqs[i], port); |
| |
| out_nomem: |
| while (--j >= 0) |
| kfree(port->irqstr[j]); |
| |
| return ret; |
| } |
| |
| static void sci_free_irq(struct sci_port *port) |
| { |
| int i; |
| |
| /* |
| * Intentionally in reverse order so we iterate over the muxed |
| * IRQ first. |
| */ |
| for (i = 0; i < SCIx_NR_IRQS; i++) { |
| int irq = port->irqs[i]; |
| |
| /* |
| * Certain port types won't support all of the available |
| * interrupt sources. |
| */ |
| if (unlikely(irq < 0)) |
| continue; |
| |
| free_irq(port->irqs[i], port); |
| kfree(port->irqstr[i]); |
| |
| if (SCIx_IRQ_IS_MUXED(port)) { |
| /* If there's only one IRQ, we're done. */ |
| return; |
| } |
| } |
| } |
| |
| static unsigned int sci_tx_empty(struct uart_port *port) |
| { |
| unsigned short status = serial_port_in(port, SCxSR); |
| unsigned short in_tx_fifo = sci_txfill(port); |
| |
| return (status & SCxSR_TEND(port)) && !in_tx_fifo ? TIOCSER_TEMT : 0; |
| } |
| |
| static void sci_set_rts(struct uart_port *port, bool state) |
| { |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| u16 data = serial_port_in(port, SCPDR); |
| |
| /* Active low */ |
| if (state) |
| data &= ~SCPDR_RTSD; |
| else |
| data |= SCPDR_RTSD; |
| serial_port_out(port, SCPDR, data); |
| |
| /* RTS# is output */ |
| serial_port_out(port, SCPCR, |
| serial_port_in(port, SCPCR) | SCPCR_RTSC); |
| } else if (sci_getreg(port, SCSPTR)->size) { |
| u16 ctrl = serial_port_in(port, SCSPTR); |
| |
| /* Active low */ |
| if (state) |
| ctrl &= ~SCSPTR_RTSDT; |
| else |
| ctrl |= SCSPTR_RTSDT; |
| serial_port_out(port, SCSPTR, ctrl); |
| } |
| } |
| |
| static bool sci_get_cts(struct uart_port *port) |
| { |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| /* Active low */ |
| return !(serial_port_in(port, SCPDR) & SCPDR_CTSD); |
| } else if (sci_getreg(port, SCSPTR)->size) { |
| /* Active low */ |
| return !(serial_port_in(port, SCSPTR) & SCSPTR_CTSDT); |
| } |
| |
| return true; |
| } |
| |
| /* |
| * Modem control is a bit of a mixed bag for SCI(F) ports. Generally |
| * CTS/RTS is supported in hardware by at least one port and controlled |
| * via SCSPTR (SCxPCR for SCIFA/B parts), or external pins (presently |
| * handled via the ->init_pins() op, which is a bit of a one-way street, |
| * lacking any ability to defer pin control -- this will later be |
| * converted over to the GPIO framework). |
| * |
| * Other modes (such as loopback) are supported generically on certain |
| * port types, but not others. For these it's sufficient to test for the |
| * existence of the support register and simply ignore the port type. |
| */ |
| static void sci_set_mctrl(struct uart_port *port, unsigned int mctrl) |
| { |
| struct sci_port *s = to_sci_port(port); |
| |
| if (mctrl & TIOCM_LOOP) { |
| const struct plat_sci_reg *reg; |
| |
| /* |
| * Standard loopback mode for SCFCR ports. |
| */ |
| reg = sci_getreg(port, SCFCR); |
| if (reg->size) |
| serial_port_out(port, SCFCR, |
| serial_port_in(port, SCFCR) | |
| SCFCR_LOOP); |
| } |
| |
| mctrl_gpio_set(s->gpios, mctrl); |
| |
| if (!(s->cfg->capabilities & SCIx_HAVE_RTSCTS)) |
| return; |
| |
| if (!(mctrl & TIOCM_RTS)) { |
| /* Disable Auto RTS */ |
| serial_port_out(port, SCFCR, |
| serial_port_in(port, SCFCR) & ~SCFCR_MCE); |
| |
| /* Clear RTS */ |
| sci_set_rts(port, 0); |
| } else if (s->autorts) { |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) { |
| /* Enable RTS# pin function */ |
| serial_port_out(port, SCPCR, |
| serial_port_in(port, SCPCR) & ~SCPCR_RTSC); |
| } |
| |
| /* Enable Auto RTS */ |
| serial_port_out(port, SCFCR, |
| serial_port_in(port, SCFCR) | SCFCR_MCE); |
| } else { |
| /* Set RTS */ |
| sci_set_rts(port, 1); |
| } |
| } |
| |
| static unsigned int sci_get_mctrl(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| struct mctrl_gpios *gpios = s->gpios; |
| unsigned int mctrl = 0; |
| |
| mctrl_gpio_get(gpios, &mctrl); |
| |
| /* |
| * CTS/RTS is handled in hardware when supported, while nothing |
| * else is wired up. |
| */ |
| if (s->autorts) { |
| if (sci_get_cts(port)) |
| mctrl |= TIOCM_CTS; |
| } else if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_CTS))) { |
| mctrl |= TIOCM_CTS; |
| } |
| if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DSR))) |
| mctrl |= TIOCM_DSR; |
| if (IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(gpios, UART_GPIO_DCD))) |
| mctrl |= TIOCM_CAR; |
| |
| return mctrl; |
| } |
| |
| static void sci_enable_ms(struct uart_port *port) |
| { |
| mctrl_gpio_enable_ms(to_sci_port(port)->gpios); |
| } |
| |
| static void sci_break_ctl(struct uart_port *port, int break_state) |
| { |
| unsigned short scscr, scsptr; |
| |
| /* check wheter the port has SCSPTR */ |
| if (!sci_getreg(port, SCSPTR)->size) { |
| /* |
| * Not supported by hardware. Most parts couple break and rx |
| * interrupts together, with break detection always enabled. |
| */ |
| return; |
| } |
| |
| scsptr = serial_port_in(port, SCSPTR); |
| scscr = serial_port_in(port, SCSCR); |
| |
| if (break_state == -1) { |
| scsptr = (scsptr | SCSPTR_SPB2IO) & ~SCSPTR_SPB2DT; |
| scscr &= ~SCSCR_TE; |
| } else { |
| scsptr = (scsptr | SCSPTR_SPB2DT) & ~SCSPTR_SPB2IO; |
| scscr |= SCSCR_TE; |
| } |
| |
| serial_port_out(port, SCSPTR, scsptr); |
| serial_port_out(port, SCSCR, scscr); |
| } |
| |
| static int sci_startup(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| int ret; |
| |
| dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); |
| |
| ret = sci_request_irq(s); |
| if (unlikely(ret < 0)) |
| return ret; |
| |
| sci_request_dma(port); |
| |
| return 0; |
| } |
| |
| static void sci_shutdown(struct uart_port *port) |
| { |
| struct sci_port *s = to_sci_port(port); |
| unsigned long flags; |
| u16 scr; |
| |
| dev_dbg(port->dev, "%s(%d)\n", __func__, port->line); |
| |
| s->autorts = false; |
| mctrl_gpio_disable_ms(to_sci_port(port)->gpios); |
| |
| spin_lock_irqsave(&port->lock, flags); |
| sci_stop_rx(port); |
| sci_stop_tx(port); |
| /* Stop RX and TX, disable related interrupts, keep clock source */ |
| scr = serial_port_in(port, SCSCR); |
| serial_port_out(port, SCSCR, scr & (SCSCR_CKE1 | SCSCR_CKE0)); |
| spin_unlock_irqrestore(&port->lock, flags); |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| if (s->chan_rx) { |
| dev_dbg(port->dev, "%s(%d) deleting rx_timer\n", __func__, |
| port->line); |
| del_timer_sync(&s->rx_timer); |
| } |
| #endif |
| |
| sci_free_dma(port); |
| sci_free_irq(s); |
| } |
| |
| static int sci_sck_calc(struct sci_port *s, unsigned int bps, |
| unsigned int *srr) |
| { |
| unsigned long freq = s->clk_rates[SCI_SCK]; |
| int err, min_err = INT_MAX; |
| unsigned int sr; |
| |
| if (s->port.type != PORT_HSCIF) |
| freq *= 2; |
| |
| for_each_sr(sr, s) { |
| err = DIV_ROUND_CLOSEST(freq, sr) - bps; |
| if (abs(err) >= abs(min_err)) |
| continue; |
| |
| min_err = err; |
| *srr = sr - 1; |
| |
| if (!err) |
| break; |
| } |
| |
| dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err, |
| *srr + 1); |
| return min_err; |
| } |
| |
| static int sci_brg_calc(struct sci_port *s, unsigned int bps, |
| unsigned long freq, unsigned int *dlr, |
| unsigned int *srr) |
| { |
| int err, min_err = INT_MAX; |
| unsigned int sr, dl; |
| |
| if (s->port.type != PORT_HSCIF) |
| freq *= 2; |
| |
| for_each_sr(sr, s) { |
| dl = DIV_ROUND_CLOSEST(freq, sr * bps); |
| dl = clamp(dl, 1U, 65535U); |
| |
| err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps; |
| if (abs(err) >= abs(min_err)) |
| continue; |
| |
| min_err = err; |
| *dlr = dl; |
| *srr = sr - 1; |
| |
| if (!err) |
| break; |
| } |
| |
| dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps, |
| min_err, *dlr, *srr + 1); |
| return min_err; |
| } |
| |
| /* calculate sample rate, BRR, and clock select */ |
| static int sci_scbrr_calc(struct sci_port *s, unsigned int bps, |
| unsigned int *brr, unsigned int *srr, |
| unsigned int *cks) |
| { |
| unsigned long freq = s->clk_rates[SCI_FCK]; |
| unsigned int sr, br, prediv, scrate, c; |
| int err, min_err = INT_MAX; |
| |
| if (s->port.type != PORT_HSCIF) |
| freq *= 2; |
| |
| /* |
| * Find the combination of sample rate and clock select with the |
| * smallest deviation from the desired baud rate. |
| * Prefer high sample rates to maximise the receive margin. |
| * |
| * M: Receive margin (%) |
| * N: Ratio of bit rate to clock (N = sampling rate) |
| * D: Clock duty (D = 0 to 1.0) |
| * L: Frame length (L = 9 to 12) |
| * F: Absolute value of clock frequency deviation |
| * |
| * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) - |
| * (|D - 0.5| / N * (1 + F))| |
| * NOTE: Usually, treat D for 0.5, F is 0 by this calculation. |
| */ |
| for_each_sr(sr, s) { |
| for (c = 0; c <= 3; c++) { |
| /* integerized formulas from HSCIF documentation */ |
| prediv = sr * (1 << (2 * c + 1)); |
| |
| /* |
| * We need to calculate: |
| * |
| * br = freq / (prediv * bps) clamped to [1..256] |
| * err = freq / (br * prediv) - bps |
| * |
| * Watch out for overflow when calculating the desired |
| * sampling clock rate! |
| */ |
| if (bps > UINT_MAX / prediv) |
| break; |
| |
| scrate = prediv * bps; |
| br = DIV_ROUND_CLOSEST(freq, scrate); |
| br = clamp(br, 1U, 256U); |
| |
| err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps; |
| if (abs(err) >= abs(min_err)) |
| continue; |
| |
| min_err = err; |
| *brr = br - 1; |
| *srr = sr - 1; |
| *cks = c; |
| |
| if (!err) |
| goto found; |
| } |
| } |
| |
| found: |
| dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps, |
| min_err, *brr, *srr + 1, *cks); |
| return min_err; |
| } |
| |
| static void sci_reset(struct uart_port *port) |
| { |
| const struct plat_sci_reg *reg; |
| unsigned int status; |
| |
| do { |
| status = serial_port_in(port, SCxSR); |
| } while (!(status & SCxSR_TEND(port))); |
| |
| serial_port_out(port, SCSCR, 0x00); /* TE=0, RE=0, CKE1=0 */ |
| |
| reg = sci_getreg(port, SCFCR); |
| if (reg->size) |
| serial_port_out(port, SCFCR, SCFCR_RFRST | SCFCR_TFRST); |
| |
| sci_clear_SCxSR(port, |
| SCxSR_RDxF_CLEAR(port) & SCxSR_ERROR_CLEAR(port) & |
| SCxSR_BREAK_CLEAR(port)); |
| if (sci_getreg(port, SCLSR)->size) { |
| status = serial_port_in(port, SCLSR); |
| status &= ~(SCLSR_TO | SCLSR_ORER); |
| serial_port_out(port, SCLSR, status); |
| } |
| } |
| |
| static void sci_set_termios(struct uart_port *port, struct ktermios *termios, |
| struct ktermios *old) |
| { |
| unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i; |
| unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0; |
| unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0; |
| struct sci_port *s = to_sci_port(port); |
| const struct plat_sci_reg *reg; |
| int min_err = INT_MAX, err; |
| unsigned long max_freq = 0; |
| int best_clk = -1; |
| |
| if ((termios->c_cflag & CSIZE) == CS7) |
| smr_val |= SCSMR_CHR; |
| if (termios->c_cflag & PARENB) |
| smr_val |= SCSMR_PE; |
| if (termios->c_cflag & PARODD) |
| smr_val |= SCSMR_PE | SCSMR_ODD; |
| if (termios->c_cflag & CSTOPB) |
| smr_val |= SCSMR_STOP; |
| |
| /* |
| * earlyprintk comes here early on with port->uartclk set to zero. |
| * the clock framework is not up and running at this point so here |
| * we assume that 115200 is the maximum baud rate. please note that |
| * the baud rate is not programmed during earlyprintk - it is assumed |
| * that the previous boot loader has enabled required clocks and |
| * setup the baud rate generator hardware for us already. |
| */ |
| if (!port->uartclk) { |
| baud = uart_get_baud_rate(port, termios, old, 0, 115200); |
| goto done; |
| } |
| |
| for (i = 0; i < SCI_NUM_CLKS; i++) |
| max_freq = max(max_freq, s->clk_rates[i]); |
| |
| baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s)); |
| if (!baud) |
| goto done; |
| |
| /* |
| * There can be multiple sources for the sampling clock. Find the one |
| * that gives us the smallest deviation from the desired baud rate. |
| */ |
| |
| /* Optional Undivided External Clock */ |
| if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA && |
| port->type != PORT_SCIFB) { |
| err = sci_sck_calc(s, baud, &srr1); |
| if (abs(err) < abs(min_err)) { |
| best_clk = SCI_SCK; |
| scr_val = SCSCR_CKE1; |
| sccks = SCCKS_CKS; |
| min_err = err; |
| srr = srr1; |
| if (!err) |
| goto done; |
| } |
| } |
| |
| /* Optional BRG Frequency Divided External Clock */ |
| if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) { |
| err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1, |
| &srr1); |
| if (abs(err) < abs(min_err)) { |
| best_clk = SCI_SCIF_CLK; |
| scr_val = SCSCR_CKE1; |
| sccks = 0; |
| min_err = err; |
| dl = dl1; |
| srr = srr1; |
| if (!err) |
| goto done; |
| } |
| } |
| |
| /* Optional BRG Frequency Divided Internal Clock */ |
| if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) { |
| err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1, |
| &srr1); |
| if (abs(err) < abs(min_err)) { |
| best_clk = SCI_BRG_INT; |
| scr_val = SCSCR_CKE1; |
| sccks = SCCKS_XIN; |
| min_err = err; |
| dl = dl1; |
| srr = srr1; |
| if (!min_err) |
| goto done; |
| } |
| } |
| |
| /* Divided Functional Clock using standard Bit Rate Register */ |
| err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1); |
| if (abs(err) < abs(min_err)) { |
| best_clk = SCI_FCK; |
| scr_val = 0; |
| min_err = err; |
| brr = brr1; |
| srr = srr1; |
| cks = cks1; |
| } |
| |
| done: |
| if (best_clk >= 0) |
| dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n", |
| s->clks[best_clk], baud, min_err); |
| |
| sci_port_enable(s); |
| |
| /* |
| * Program the optional External Baud Rate Generator (BRG) first. |
| * It controls the mux to select (H)SCK or frequency divided clock. |
| */ |
| if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) { |
| serial_port_out(port, SCDL, dl); |
| serial_port_out(port, SCCKS, sccks); |
| } |
| |
| sci_reset(port); |
| |
| uart_update_timeout(port, termios->c_cflag, baud); |
| |
| if (best_clk >= 0) { |
| if (port->type == PORT_SCIFA || port->type == PORT_SCIFB) |
| switch (srr + 1) { |
| case 5: smr_val |= SCSMR_SRC_5; break; |
| case 7: smr_val |= SCSMR_SRC_7; break; |
| case 11: smr_val |= SCSMR_SRC_11; break; |
| case 13: smr_val |= SCSMR_SRC_13; break; |
| case 16: smr_val |= SCSMR_SRC_16; break; |
| case 17: smr_val |= SCSMR_SRC_17; break; |
| case 19: smr_val |= SCSMR_SRC_19; break; |
| case 27: smr_val |= SCSMR_SRC_27; break; |
| } |
| smr_val |= cks; |
| dev_dbg(port->dev, |
| "SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n", |
| scr_val, smr_val, brr, sccks, dl, srr); |
| serial_port_out(port, SCSCR, scr_val); |
| serial_port_out(port, SCSMR, smr_val); |
| serial_port_out(port, SCBRR, brr); |
| if (sci_getreg(port, HSSRR)->size) |
| serial_port_out(port, HSSRR, srr | HSCIF_SRE); |
| |
| /* Wait one bit interval */ |
| udelay((1000000 + (baud - 1)) / baud); |
| } else { |
| /* Don't touch the bit rate configuration */ |
| scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0); |
| smr_val |= serial_port_in(port, SCSMR) & |
| (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS); |
| dev_dbg(port->dev, "SCR 0x%x SMR 0x%x\n", scr_val, smr_val); |
| serial_port_out(port, SCSCR, scr_val); |
| serial_port_out(port, SCSMR, smr_val); |
| } |
| |
| sci_init_pins(port, termios->c_cflag); |
| |
| port->status &= ~UPSTAT_AUTOCTS; |
| s->autorts = false; |
| reg = sci_getreg(port, SCFCR); |
| if (reg->size) { |
| unsigned short ctrl = serial_port_in(port, SCFCR); |
| |
| if ((port->flags & UPF_HARD_FLOW) && |
| (termios->c_cflag & CRTSCTS)) { |
| /* There is no CTS interrupt to restart the hardware */ |
| port->status |= UPSTAT_AUTOCTS; |
| /* MCE is enabled when RTS is raised */ |
| s->autorts = true; |
| } |
| |
| /* |
| * As we've done a sci_reset() above, ensure we don't |
| * interfere with the FIFOs while toggling MCE. As the |
| * reset values could still be set, simply mask them out. |
| */ |
| ctrl &= ~(SCFCR_RFRST | SCFCR_TFRST); |
| |
| serial_port_out(port, SCFCR, ctrl); |
| } |
| |
| scr_val |= s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0); |
| dev_dbg(port->dev, "SCSCR 0x%x\n", scr_val); |
| serial_port_out(port, SCSCR, scr_val); |
| if ((srr + 1 == 5) && |
| (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) { |
| /* |
| * In asynchronous mode, when the sampling rate is 1/5, first |
| * received data may become invalid on some SCIFA and SCIFB. |
| * To avoid this problem wait more than 1 serial data time (1 |
| * bit time x serial data number) after setting SCSCR.RE = 1. |
| */ |
| udelay(DIV_ROUND_UP(10 * 1000000, baud)); |
| } |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_DMA |
| /* |
| * Calculate delay for 2 DMA buffers (4 FIFO). |
| * See serial_core.c::uart_update_timeout(). |
| * With 10 bits (CS8), 250Hz, 115200 baud and 64 bytes FIFO, the above |
| * function calculates 1 jiffie for the data plus 5 jiffies for the |
| * "slop(e)." Then below we calculate 5 jiffies (20ms) for 2 DMA |
| * buffers (4 FIFO sizes), but when performing a faster transfer, the |
| * value obtained by this formula is too small. Therefore, if the value |
| * is smaller than 20ms, use 20ms as the timeout value for DMA. |
| */ |
| if (s->chan_rx) { |
| unsigned int bits; |
| |
| /* byte size and parity */ |
| switch (termios->c_cflag & CSIZE) { |
| case CS5: |
| bits = 7; |
| break; |
| case CS6: |
| bits = 8; |
| break; |
| case CS7: |
| bits = 9; |
| break; |
| default: |
| bits = 10; |
| break; |
| } |
| |
| if (termios->c_cflag & CSTOPB) |
| bits++; |
| if (termios->c_cflag & PARENB) |
| bits++; |
| s->rx_timeout = DIV_ROUND_UP((s->buf_len_rx * 2 * bits * HZ) / |
| (baud / 10), 10); |
| dev_dbg(port->dev, "DMA Rx t-out %ums, tty t-out %u jiffies\n", |
| s->rx_timeout * 1000 / HZ, port->timeout); |
| if (s->rx_timeout < msecs_to_jiffies(20)) |
| s->rx_timeout = msecs_to_jiffies(20); |
| } |
| #endif |
| |
| if ((termios->c_cflag & CREAD) != 0) |
| sci_start_rx(port); |
| |
| sci_port_disable(s); |
| |
| if (UART_ENABLE_MS(port, termios->c_cflag)) |
| sci_enable_ms(port); |
| } |
| |
| static void sci_pm(struct uart_port *port, unsigned int state, |
| unsigned int oldstate) |
| { |
| struct sci_port *sci_port = to_sci_port(port); |
| |
| switch (state) { |
| case UART_PM_STATE_OFF: |
| sci_port_disable(sci_port); |
| break; |
| default: |
| sci_port_enable(sci_port); |
| break; |
| } |
| } |
| |
| static const char *sci_type(struct uart_port *port) |
| { |
| switch (port->type) { |
| case PORT_IRDA: |
| return "irda"; |
| case PORT_SCI: |
| return "sci"; |
| case PORT_SCIF: |
| return "scif"; |
| case PORT_SCIFA: |
| return "scifa"; |
| case PORT_SCIFB: |
| return "scifb"; |
| case PORT_HSCIF: |
| return "hscif"; |
| } |
| |
| return NULL; |
| } |
| |
| static int sci_remap_port(struct uart_port *port) |
| { |
| struct sci_port *sport = to_sci_port(port); |
| |
| /* |
| * Nothing to do if there's already an established membase. |
| */ |
| if (port->membase) |
| return 0; |
| |
| if (port->flags & UPF_IOREMAP) { |
| port->membase = ioremap_nocache(port->mapbase, sport->reg_size); |
| if (unlikely(!port->membase)) { |
| dev_err(port->dev, "can't remap port#%d\n", port->line); |
| return -ENXIO; |
| } |
| } else { |
| /* |
| * For the simple (and majority of) cases where we don't |
| * need to do any remapping, just cast the cookie |
| * directly. |
| */ |
| port->membase = (void __iomem *)(uintptr_t)port->mapbase; |
| } |
| |
| return 0; |
| } |
| |
| static void sci_release_port(struct uart_port *port) |
| { |
| struct sci_port *sport = to_sci_port(port); |
| |
| if (port->flags & UPF_IOREMAP) { |
| iounmap(port->membase); |
| port->membase = NULL; |
| } |
| |
| release_mem_region(port->mapbase, sport->reg_size); |
| } |
| |
| static int sci_request_port(struct uart_port *port) |
| { |
| struct resource *res; |
| struct sci_port *sport = to_sci_port(port); |
| int ret; |
| |
| res = request_mem_region(port->mapbase, sport->reg_size, |
| dev_name(port->dev)); |
| if (unlikely(res == NULL)) { |
| dev_err(port->dev, "request_mem_region failed."); |
| return -EBUSY; |
| } |
| |
| ret = sci_remap_port(port); |
| if (unlikely(ret != 0)) { |
| release_resource(res); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static void sci_config_port(struct uart_port *port, int flags) |
| { |
| if (flags & UART_CONFIG_TYPE) { |
| struct sci_port *sport = to_sci_port(port); |
| |
| port->type = sport->cfg->type; |
| sci_request_port(port); |
| } |
| } |
| |
| static int sci_verify_port(struct uart_port *port, struct serial_struct *ser) |
| { |
| if (ser->baud_base < 2400) |
| /* No paper tape reader for Mitch.. */ |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static const struct uart_ops sci_uart_ops = { |
| .tx_empty = sci_tx_empty, |
| .set_mctrl = sci_set_mctrl, |
| .get_mctrl = sci_get_mctrl, |
| .start_tx = sci_start_tx, |
| .stop_tx = sci_stop_tx, |
| .stop_rx = sci_stop_rx, |
| .enable_ms = sci_enable_ms, |
| .break_ctl = sci_break_ctl, |
| .startup = sci_startup, |
| .shutdown = sci_shutdown, |
| .set_termios = sci_set_termios, |
| .pm = sci_pm, |
| .type = sci_type, |
| .release_port = sci_release_port, |
| .request_port = sci_request_port, |
| .config_port = sci_config_port, |
| .verify_port = sci_verify_port, |
| #ifdef CONFIG_CONSOLE_POLL |
| .poll_get_char = sci_poll_get_char, |
| .poll_put_char = sci_poll_put_char, |
| #endif |
| }; |
| |
| static int sci_init_clocks(struct sci_port *sci_port, struct device *dev) |
| { |
| const char *clk_names[] = { |
| [SCI_FCK] = "fck", |
| [SCI_SCK] = "sck", |
| [SCI_BRG_INT] = "brg_int", |
| [SCI_SCIF_CLK] = "scif_clk", |
| }; |
| struct clk *clk; |
| unsigned int i; |
| |
| if (sci_port->cfg->type == PORT_HSCIF) |
| clk_names[SCI_SCK] = "hsck"; |
| |
| for (i = 0; i < SCI_NUM_CLKS; i++) { |
| clk = devm_clk_get(dev, clk_names[i]); |
| if (PTR_ERR(clk) == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| |
| if (IS_ERR(clk) && i == SCI_FCK) { |
| /* |
| * "fck" used to be called "sci_ick", and we need to |
| * maintain DT backward compatibility. |
| */ |
| clk = devm_clk_get(dev, "sci_ick"); |
| if (PTR_ERR(clk) == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| |
| if (!IS_ERR(clk)) |
| goto found; |
| |
| /* |
| * Not all SH platforms declare a clock lookup entry |
| * for SCI devices, in which case we need to get the |
| * global "peripheral_clk" clock. |
| */ |
| clk = devm_clk_get(dev, "peripheral_clk"); |
| if (!IS_ERR(clk)) |
| goto found; |
| |
| dev_err(dev, "failed to get %s (%ld)\n", clk_names[i], |
| PTR_ERR(clk)); |
| return PTR_ERR(clk); |
| } |
| |
| found: |
| if (IS_ERR(clk)) |
| dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i], |
| PTR_ERR(clk)); |
| else |
| dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i], |
| clk, clk); |
| sci_port->clks[i] = IS_ERR(clk) ? NULL : clk; |
| } |
| return 0; |
| } |
| |
| static int sci_init_single(struct platform_device *dev, |
| struct sci_port *sci_port, unsigned int index, |
| struct plat_sci_port *p, bool early) |
| { |
| struct uart_port *port = &sci_port->port; |
| const struct resource *res; |
| unsigned int i; |
| int ret; |
| |
| sci_port->cfg = p; |
| |
| port->ops = &sci_uart_ops; |
| port->iotype = UPIO_MEM; |
| port->line = index; |
| |
| res = platform_get_resource(dev, IORESOURCE_MEM, 0); |
| if (res == NULL) |
| return -ENOMEM; |
| |
| port->mapbase = res->start; |
| sci_port->reg_size = resource_size(res); |
| |
| for (i = 0; i < ARRAY_SIZE(sci_port->irqs); ++i) |
| sci_port->irqs[i] = platform_get_irq(dev, i); |
| |
| /* The SCI generates several interrupts. They can be muxed together or |
| * connected to different interrupt lines. In the muxed case only one |
| * interrupt resource is specified. In the non-muxed case three or four |
| * interrupt resources are specified, as the BRI interrupt is optional. |
| */ |
| if (sci_port->irqs[0] < 0) |
| return -ENXIO; |
| |
| if (sci_port->irqs[1] < 0) { |
| sci_port->irqs[1] = sci_port->irqs[0]; |
| sci_port->irqs[2] = sci_port->irqs[0]; |
| sci_port->irqs[3] = sci_port->irqs[0]; |
| } |
| |
| if (p->regtype == SCIx_PROBE_REGTYPE) { |
| ret = sci_probe_regmap(p); |
| if (unlikely(ret)) |
| return ret; |
| } |
| |
| switch (p->type) { |
| case PORT_SCIFB: |
| port->fifosize = 256; |
| sci_port->overrun_reg = SCxSR; |
| sci_port->overrun_mask = SCIFA_ORER; |
| sci_port->sampling_rate_mask = SCI_SR_SCIFAB; |
| break; |
| case PORT_HSCIF: |
| port->fifosize = 128; |
| sci_port->overrun_reg = SCLSR; |
| sci_port->overrun_mask = SCLSR_ORER; |
| sci_port->sampling_rate_mask = SCI_SR_RANGE(8, 32); |
| break; |
| case PORT_SCIFA: |
| port->fifosize = 64; |
| sci_port->overrun_reg = SCxSR; |
| sci_port->overrun_mask = SCIFA_ORER; |
| sci_port->sampling_rate_mask = SCI_SR_SCIFAB; |
| break; |
| case PORT_SCIF: |
| port->fifosize = 16; |
| if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) { |
| sci_port->overrun_reg = SCxSR; |
| sci_port->overrun_mask = SCIFA_ORER; |
| sci_port->sampling_rate_mask = SCI_SR(16); |
| } else { |
| sci_port->overrun_reg = SCLSR; |
| sci_port->overrun_mask = SCLSR_ORER; |
| sci_port->sampling_rate_mask = SCI_SR(32); |
| } |
| break; |
| default: |
| port->fifosize = 1; |
| sci_port->overrun_reg = SCxSR; |
| sci_port->overrun_mask = SCI_ORER; |
| sci_port->sampling_rate_mask = SCI_SR(32); |
| break; |
| } |
| |
| /* SCIFA on sh7723 and sh7724 need a custom sampling rate that doesn't |
| * match the SoC datasheet, this should be investigated. Let platform |
| * data override the sampling rate for now. |
| */ |
| if (p->sampling_rate) |
| sci_port->sampling_rate_mask = SCI_SR(p->sampling_rate); |
| |
| if (!early) { |
| ret = sci_init_clocks(sci_port, &dev->dev); |
| if (ret < 0) |
| return ret; |
| |
| port->dev = &dev->dev; |
| |
| pm_runtime_enable(&dev->dev); |
| } |
| |
| sci_port->break_timer.data = (unsigned long)sci_port; |
| sci_port->break_timer.function = sci_break_timer; |
| init_timer(&sci_port->break_timer); |
| |
| /* |
| * Establish some sensible defaults for the error detection. |
| */ |
| if (p->type == PORT_SCI) { |
| sci_port->error_mask = SCI_DEFAULT_ERROR_MASK; |
| sci_port->error_clear = SCI_ERROR_CLEAR; |
| } else { |
| sci_port->error_mask = SCIF_DEFAULT_ERROR_MASK; |
| sci_port->error_clear = SCIF_ERROR_CLEAR; |
| } |
| |
| /* |
| * Make the error mask inclusive of overrun detection, if |
| * supported. |
| */ |
| if (sci_port->overrun_reg == SCxSR) { |
| sci_port->error_mask |= sci_port->overrun_mask; |
| sci_port->error_clear &= ~sci_port->overrun_mask; |
| } |
| |
| port->type = p->type; |
| port->flags = UPF_FIXED_PORT | p->flags; |
| port->regshift = p->regshift; |
| |
| /* |
| * The UART port needs an IRQ value, so we peg this to the RX IRQ |
| * for the multi-IRQ ports, which is where we are primarily |
| * concerned with the shutdown path synchronization. |
| * |
| * For the muxed case there's nothing more to do. |
| */ |
| port->irq = sci_port->irqs[SCIx_RXI_IRQ]; |
| port->irqflags = 0; |
| |
| port->serial_in = sci_serial_in; |
| port->serial_out = sci_serial_out; |
| |
| if (p->dma_slave_tx > 0 && p->dma_slave_rx > 0) |
| dev_dbg(port->dev, "DMA tx %d, rx %d\n", |
| p->dma_slave_tx, p->dma_slave_rx); |
| |
| return 0; |
| } |
| |
| static void sci_cleanup_single(struct sci_port *port) |
| { |
| pm_runtime_disable(port->port.dev); |
| } |
| |
| #if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \ |
| defined(CONFIG_SERIAL_SH_SCI_EARLYCON) |
| static void serial_console_putchar(struct uart_port *port, int ch) |
| { |
| sci_poll_put_char(port, ch); |
| } |
| |
| /* |
| * Print a string to the serial port trying not to disturb |
| * any possible real use of the port... |
| */ |
| static void serial_console_write(struct console *co, const char *s, |
| unsigned count) |
| { |
| struct sci_port *sci_port = &sci_ports[co->index]; |
| struct uart_port *port = &sci_port->port; |
| unsigned short bits, ctrl, ctrl_temp; |
| unsigned long flags; |
| int locked = 1; |
| |
| local_irq_save(flags); |
| #if defined(SUPPORT_SYSRQ) |
| if (port->sysrq) |
| locked = 0; |
| else |
| #endif |
| if (oops_in_progress) |
| locked = spin_trylock(&port->lock); |
| else |
| spin_lock(&port->lock); |
| |
| /* first save SCSCR then disable interrupts, keep clock source */ |
| ctrl = serial_port_in(port, SCSCR); |
| ctrl_temp = (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) | |
| (ctrl & (SCSCR_CKE1 | SCSCR_CKE0)); |
| serial_port_out(port, SCSCR, ctrl_temp); |
| |
| uart_console_write(port, s, count, serial_console_putchar); |
| |
| /* wait until fifo is empty and last bit has been transmitted */ |
| bits = SCxSR_TDxE(port) | SCxSR_TEND(port); |
| while ((serial_port_in(port, SCxSR) & bits) != bits) |
| cpu_relax(); |
| |
| /* restore the SCSCR */ |
| serial_port_out(port, SCSCR, ctrl); |
| |
| if (locked) |
| spin_unlock(&port->lock); |
| local_irq_restore(flags); |
| } |
| |
| static int serial_console_setup(struct console *co, char *options) |
| { |
| struct sci_port *sci_port; |
| struct uart_port *port; |
| int baud = 115200; |
| int bits = 8; |
| int parity = 'n'; |
| int flow = 'n'; |
| int ret; |
| |
| /* |
| * Refuse to handle any bogus ports. |
| */ |
| if (co->index < 0 || co->index >= SCI_NPORTS) |
| return -ENODEV; |
| |
| sci_port = &sci_ports[co->index]; |
| port = &sci_port->port; |
| |
| /* |
| * Refuse to handle uninitialized ports. |
| */ |
| if (!port->ops) |
| return -ENODEV; |
| |
| ret = sci_remap_port(port); |
| if (unlikely(ret != 0)) |
| return ret; |
| |
| if (options) |
| uart_parse_options(options, &baud, &parity, &bits, &flow); |
| |
| return uart_set_options(port, co, baud, parity, bits, flow); |
| } |
| |
| static struct console serial_console = { |
| .name = "ttySC", |
| .device = uart_console_device, |
| .write = serial_console_write, |
| .setup = serial_console_setup, |
| .flags = CON_PRINTBUFFER, |
| .index = -1, |
| .data = &sci_uart_driver, |
| }; |
| |
| static struct console early_serial_console = { |
| .name = "early_ttySC", |
| .write = serial_console_write, |
| .flags = CON_PRINTBUFFER, |
| .index = -1, |
| }; |
| |
| static char early_serial_buf[32]; |
| |
| static int sci_probe_earlyprintk(struct platform_device *pdev) |
| { |
| struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev); |
| |
| if (early_serial_console.data) |
| return -EEXIST; |
| |
| early_serial_console.index = pdev->id; |
| |
| sci_init_single(pdev, &sci_ports[pdev->id], pdev->id, cfg, true); |
| |
| serial_console_setup(&early_serial_console, early_serial_buf); |
| |
| if (!strstr(early_serial_buf, "keep")) |
| early_serial_console.flags |= CON_BOOT; |
| |
| register_console(&early_serial_console); |
| return 0; |
| } |
| |
| #define SCI_CONSOLE (&serial_console) |
| |
| #else |
| static inline int sci_probe_earlyprintk(struct platform_device *pdev) |
| { |
| return -EINVAL; |
| } |
| |
| #define SCI_CONSOLE NULL |
| |
| #endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */ |
| |
| static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized"; |
| |
| static struct uart_driver sci_uart_driver = { |
| .owner = THIS_MODULE, |
| .driver_name = "sci", |
| .dev_name = "ttySC", |
| .major = SCI_MAJOR, |
| .minor = SCI_MINOR_START, |
| .nr = SCI_NPORTS, |
| .cons = SCI_CONSOLE, |
| }; |
| |
| static int sci_remove(struct platform_device *dev) |
| { |
| struct sci_port *port = platform_get_drvdata(dev); |
| |
| uart_remove_one_port(&sci_uart_driver, &port->port); |
| |
| sci_cleanup_single(port); |
| |
| return 0; |
| } |
| |
| |
| #define SCI_OF_DATA(type, regtype) (void *)((type) << 16 | (regtype)) |
| #define SCI_OF_TYPE(data) ((unsigned long)(data) >> 16) |
| #define SCI_OF_REGTYPE(data) ((unsigned long)(data) & 0xffff) |
| |
| static const struct of_device_id of_sci_match[] = { |
| /* SoC-specific types */ |
| { |
| .compatible = "renesas,scif-r7s72100", |
| .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE), |
| }, |
| /* Family-specific types */ |
| { |
| .compatible = "renesas,rcar-gen1-scif", |
| .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE), |
| }, { |
| .compatible = "renesas,rcar-gen2-scif", |
| .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE), |
| }, { |
| .compatible = "renesas,rcar-gen3-scif", |
| .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE), |
| }, |
| /* Generic types */ |
| { |
| .compatible = "renesas,scif", |
| .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE), |
| }, { |
| .compatible = "renesas,scifa", |
| .data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE), |
| }, { |
| .compatible = "renesas,scifb", |
| .data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE), |
| }, { |
| .compatible = "renesas,hscif", |
| .data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE), |
| }, { |
| .compatible = "renesas,sci", |
| .data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE), |
| }, { |
| /* Terminator */ |
| }, |
| }; |
| MODULE_DEVICE_TABLE(of, of_sci_match); |
| |
| static struct plat_sci_port * |
| sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id) |
| { |
| struct device_node *np = pdev->dev.of_node; |
| const struct of_device_id *match; |
| struct plat_sci_port *p; |
| int id; |
| |
| if (!IS_ENABLED(CONFIG_OF) || !np) |
| return NULL; |
| |
| match = of_match_node(of_sci_match, np); |
| if (!match) |
| return NULL; |
| |
| p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL); |
| if (!p) |
| return NULL; |
| |
| /* Get the line number from the aliases node. */ |
| id = of_alias_get_id(np, "serial"); |
| if (id < 0) { |
| dev_err(&pdev->dev, "failed to get alias id (%d)\n", id); |
| return NULL; |
| } |
| |
| *dev_id = id; |
| |
| p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; |
| p->type = SCI_OF_TYPE(match->data); |
| p->regtype = SCI_OF_REGTYPE(match->data); |
| p->scscr = SCSCR_RE | SCSCR_TE; |
| |
| if (of_find_property(np, "uart-has-rtscts", NULL)) |
| p->capabilities |= SCIx_HAVE_RTSCTS; |
| |
| return p; |
| } |
| |
| static int sci_probe_single(struct platform_device *dev, |
| unsigned int index, |
| struct plat_sci_port *p, |
| struct sci_port *sciport) |
| { |
| int ret; |
| |
| /* Sanity check */ |
| if (unlikely(index >= SCI_NPORTS)) { |
| dev_notice(&dev->dev, "Attempting to register port %d when only %d are available\n", |
| index+1, SCI_NPORTS); |
| dev_notice(&dev->dev, "Consider bumping CONFIG_SERIAL_SH_SCI_NR_UARTS!\n"); |
| return -EINVAL; |
| } |
| |
| ret = sci_init_single(dev, sciport, index, p, false); |
| if (ret) |
| return ret; |
| |
| sciport->gpios = mctrl_gpio_init(&sciport->port, 0); |
| if (IS_ERR(sciport->gpios) && PTR_ERR(sciport->gpios) != -ENOSYS) |
| return PTR_ERR(sciport->gpios); |
| |
| if (p->capabilities & SCIx_HAVE_RTSCTS) { |
| if (!IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios, |
| UART_GPIO_CTS)) || |
| !IS_ERR_OR_NULL(mctrl_gpio_to_gpiod(sciport->gpios, |
| UART_GPIO_RTS))) { |
| dev_err(&dev->dev, "Conflicting RTS/CTS config\n"); |
| return -EINVAL; |
| } |
| sciport->port.flags |= UPF_HARD_FLOW; |
| } |
| |
| ret = uart_add_one_port(&sci_uart_driver, &sciport->port); |
| if (ret) { |
| sci_cleanup_single(sciport); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int sci_probe(struct platform_device *dev) |
| { |
| struct plat_sci_port *p; |
| struct sci_port *sp; |
| unsigned int dev_id; |
| int ret; |
| |
| /* |
| * If we've come here via earlyprintk initialization, head off to |
| * the special early probe. We don't have sufficient device state |
| * to make it beyond this yet. |
| */ |
| if (is_early_platform_device(dev)) |
| return sci_probe_earlyprintk(dev); |
| |
| if (dev->dev.of_node) { |
| p = sci_parse_dt(dev, &dev_id); |
| if (p == NULL) |
| return -EINVAL; |
| } else { |
| p = dev->dev.platform_data; |
| if (p == NULL) { |
| dev_err(&dev->dev, "no platform data supplied\n"); |
| return -EINVAL; |
| } |
| |
| dev_id = dev->id; |
| } |
| |
| sp = &sci_ports[dev_id]; |
| platform_set_drvdata(dev, sp); |
| |
| ret = sci_probe_single(dev, dev_id, p, sp); |
| if (ret) |
| return ret; |
| |
| #ifdef CONFIG_SH_STANDARD_BIOS |
| sh_bios_gdb_detach(); |
| #endif |
| |
| return 0; |
| } |
| |
| static __maybe_unused int sci_suspend(struct device *dev) |
| { |
| struct sci_port *sport = dev_get_drvdata(dev); |
| |
| if (sport) |
| uart_suspend_port(&sci_uart_driver, &sport->port); |
| |
| return 0; |
| } |
| |
| static __maybe_unused int sci_resume(struct device *dev) |
| { |
| struct sci_port *sport = dev_get_drvdata(dev); |
| |
| if (sport) |
| uart_resume_port(&sci_uart_driver, &sport->port); |
| |
| return 0; |
| } |
| |
| static SIMPLE_DEV_PM_OPS(sci_dev_pm_ops, sci_suspend, sci_resume); |
| |
| static struct platform_driver sci_driver = { |
| .probe = sci_probe, |
| .remove = sci_remove, |
| .driver = { |
| .name = "sh-sci", |
| .pm = &sci_dev_pm_ops, |
| .of_match_table = of_match_ptr(of_sci_match), |
| }, |
| }; |
| |
| static int __init sci_init(void) |
| { |
| int ret; |
| |
| pr_info("%s\n", banner); |
| |
| ret = uart_register_driver(&sci_uart_driver); |
| if (likely(ret == 0)) { |
| ret = platform_driver_register(&sci_driver); |
| if (unlikely(ret)) |
| uart_unregister_driver(&sci_uart_driver); |
| } |
| |
| return ret; |
| } |
| |
| static void __exit sci_exit(void) |
| { |
| platform_driver_unregister(&sci_driver); |
| uart_unregister_driver(&sci_uart_driver); |
| } |
| |
| #ifdef CONFIG_SERIAL_SH_SCI_CONSOLE |
| early_platform_init_buffer("earlyprintk", &sci_driver, |
| early_serial_buf, ARRAY_SIZE(early_serial_buf)); |
| #endif |
| #ifdef CONFIG_SERIAL_SH_SCI_EARLYCON |
| static struct __init plat_sci_port port_cfg; |
| |
| static int __init early_console_setup(struct earlycon_device *device, |
| int type) |
| { |
| if (!device->port.membase) |
| return -ENODEV; |
| |
| device->port.serial_in = sci_serial_in; |
| device->port.serial_out = sci_serial_out; |
| device->port.type = type; |
| memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port)); |
| sci_ports[0].cfg = &port_cfg; |
| sci_ports[0].cfg->type = type; |
| sci_probe_regmap(sci_ports[0].cfg); |
| port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR) | |
| SCSCR_RE | SCSCR_TE; |
| sci_serial_out(&sci_ports[0].port, SCSCR, port_cfg.scscr); |
| |
| device->con->write = serial_console_write; |
| return 0; |
| } |
| static int __init sci_early_console_setup(struct earlycon_device *device, |
| const char *opt) |
| { |
| return early_console_setup(device, PORT_SCI); |
| } |
| static int __init scif_early_console_setup(struct earlycon_device *device, |
| const char *opt) |
| { |
| return early_console_setup(device, PORT_SCIF); |
| } |
| static int __init scifa_early_console_setup(struct earlycon_device *device, |
| const char *opt) |
| { |
| return early_console_setup(device, PORT_SCIFA); |
| } |
| static int __init scifb_early_console_setup(struct earlycon_device *device, |
| const char *opt) |
| { |
| return early_console_setup(device, PORT_SCIFB); |
| } |
| static int __init hscif_early_console_setup(struct earlycon_device *device, |
| const char *opt) |
| { |
| return early_console_setup(device, PORT_HSCIF); |
| } |
| |
| OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup); |
| OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup); |
| OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup); |
| OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup); |
| OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup); |
| #endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */ |
| |
| module_init(sci_init); |
| module_exit(sci_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:sh-sci"); |
| MODULE_AUTHOR("Paul Mundt"); |
| MODULE_DESCRIPTION("SuperH (H)SCI(F) serial driver"); |