| // SPDX-License-Identifier: GPL-2.0-only |
| /* sun3x_esp.c: ESP front-end for Sun3x systems. |
| * |
| * Copyright (C) 2007,2008 Thomas Bogendoerfer (tsbogend@alpha.franken.de) |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/gfp.h> |
| #include <linux/types.h> |
| #include <linux/delay.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/platform_device.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| |
| #include <asm/sun3x.h> |
| #include <asm/dma.h> |
| #include <asm/dvma.h> |
| |
| /* DMA controller reg offsets */ |
| #define DMA_CSR 0x00UL /* rw DMA control/status register 0x00 */ |
| #define DMA_ADDR 0x04UL /* rw DMA transfer address register 0x04 */ |
| #define DMA_COUNT 0x08UL /* rw DMA transfer count register 0x08 */ |
| #define DMA_TEST 0x0cUL /* rw DMA test/debug register 0x0c */ |
| |
| #include <scsi/scsi_host.h> |
| |
| #include "esp_scsi.h" |
| |
| #define DRV_MODULE_NAME "sun3x_esp" |
| #define PFX DRV_MODULE_NAME ": " |
| #define DRV_VERSION "1.000" |
| #define DRV_MODULE_RELDATE "Nov 1, 2007" |
| |
| /* |
| * m68k always assumes readl/writel operate on little endian |
| * mmio space; this is wrong at least for Sun3x, so we |
| * need to workaround this until a proper way is found |
| */ |
| #if 0 |
| #define dma_read32(REG) \ |
| readl(esp->dma_regs + (REG)) |
| #define dma_write32(VAL, REG) \ |
| writel((VAL), esp->dma_regs + (REG)) |
| #else |
| #define dma_read32(REG) \ |
| *(volatile u32 *)(esp->dma_regs + (REG)) |
| #define dma_write32(VAL, REG) \ |
| do { *(volatile u32 *)(esp->dma_regs + (REG)) = (VAL); } while (0) |
| #endif |
| |
| static void sun3x_esp_write8(struct esp *esp, u8 val, unsigned long reg) |
| { |
| writeb(val, esp->regs + (reg * 4UL)); |
| } |
| |
| static u8 sun3x_esp_read8(struct esp *esp, unsigned long reg) |
| { |
| return readb(esp->regs + (reg * 4UL)); |
| } |
| |
| static int sun3x_esp_irq_pending(struct esp *esp) |
| { |
| if (dma_read32(DMA_CSR) & (DMA_HNDL_INTR | DMA_HNDL_ERROR)) |
| return 1; |
| return 0; |
| } |
| |
| static void sun3x_esp_reset_dma(struct esp *esp) |
| { |
| u32 val; |
| |
| val = dma_read32(DMA_CSR); |
| dma_write32(val | DMA_RST_SCSI, DMA_CSR); |
| dma_write32(val & ~DMA_RST_SCSI, DMA_CSR); |
| |
| /* Enable interrupts. */ |
| val = dma_read32(DMA_CSR); |
| dma_write32(val | DMA_INT_ENAB, DMA_CSR); |
| } |
| |
| static void sun3x_esp_dma_drain(struct esp *esp) |
| { |
| u32 csr; |
| int lim; |
| |
| csr = dma_read32(DMA_CSR); |
| if (!(csr & DMA_FIFO_ISDRAIN)) |
| return; |
| |
| dma_write32(csr | DMA_FIFO_STDRAIN, DMA_CSR); |
| |
| lim = 1000; |
| while (dma_read32(DMA_CSR) & DMA_FIFO_ISDRAIN) { |
| if (--lim == 0) { |
| printk(KERN_ALERT PFX "esp%d: DMA will not drain!\n", |
| esp->host->unique_id); |
| break; |
| } |
| udelay(1); |
| } |
| } |
| |
| static void sun3x_esp_dma_invalidate(struct esp *esp) |
| { |
| u32 val; |
| int lim; |
| |
| lim = 1000; |
| while ((val = dma_read32(DMA_CSR)) & DMA_PEND_READ) { |
| if (--lim == 0) { |
| printk(KERN_ALERT PFX "esp%d: DMA will not " |
| "invalidate!\n", esp->host->unique_id); |
| break; |
| } |
| udelay(1); |
| } |
| |
| val &= ~(DMA_ENABLE | DMA_ST_WRITE | DMA_BCNT_ENAB); |
| val |= DMA_FIFO_INV; |
| dma_write32(val, DMA_CSR); |
| val &= ~DMA_FIFO_INV; |
| dma_write32(val, DMA_CSR); |
| } |
| |
| static void sun3x_esp_send_dma_cmd(struct esp *esp, u32 addr, u32 esp_count, |
| u32 dma_count, int write, u8 cmd) |
| { |
| u32 csr; |
| |
| BUG_ON(!(cmd & ESP_CMD_DMA)); |
| |
| sun3x_esp_write8(esp, (esp_count >> 0) & 0xff, ESP_TCLOW); |
| sun3x_esp_write8(esp, (esp_count >> 8) & 0xff, ESP_TCMED); |
| csr = dma_read32(DMA_CSR); |
| csr |= DMA_ENABLE; |
| if (write) |
| csr |= DMA_ST_WRITE; |
| else |
| csr &= ~DMA_ST_WRITE; |
| dma_write32(csr, DMA_CSR); |
| dma_write32(addr, DMA_ADDR); |
| |
| scsi_esp_cmd(esp, cmd); |
| } |
| |
| static int sun3x_esp_dma_error(struct esp *esp) |
| { |
| u32 csr = dma_read32(DMA_CSR); |
| |
| if (csr & DMA_HNDL_ERROR) |
| return 1; |
| |
| return 0; |
| } |
| |
| static const struct esp_driver_ops sun3x_esp_ops = { |
| .esp_write8 = sun3x_esp_write8, |
| .esp_read8 = sun3x_esp_read8, |
| .irq_pending = sun3x_esp_irq_pending, |
| .reset_dma = sun3x_esp_reset_dma, |
| .dma_drain = sun3x_esp_dma_drain, |
| .dma_invalidate = sun3x_esp_dma_invalidate, |
| .send_dma_cmd = sun3x_esp_send_dma_cmd, |
| .dma_error = sun3x_esp_dma_error, |
| }; |
| |
| static int esp_sun3x_probe(struct platform_device *dev) |
| { |
| const struct scsi_host_template *tpnt = &scsi_esp_template; |
| struct Scsi_Host *host; |
| struct esp *esp; |
| struct resource *res; |
| int err = -ENOMEM; |
| |
| host = scsi_host_alloc(tpnt, sizeof(struct esp)); |
| if (!host) |
| goto fail; |
| |
| host->max_id = 8; |
| esp = shost_priv(host); |
| |
| esp->host = host; |
| esp->dev = &dev->dev; |
| esp->ops = &sun3x_esp_ops; |
| |
| res = platform_get_resource(dev, IORESOURCE_MEM, 0); |
| if (!res || !res->start) |
| goto fail_unlink; |
| |
| esp->regs = ioremap(res->start, 0x20); |
| if (!esp->regs) |
| goto fail_unmap_regs; |
| |
| res = platform_get_resource(dev, IORESOURCE_MEM, 1); |
| if (!res || !res->start) |
| goto fail_unmap_regs; |
| |
| esp->dma_regs = ioremap(res->start, 0x10); |
| |
| esp->command_block = dma_alloc_coherent(esp->dev, 16, |
| &esp->command_block_dma, |
| GFP_KERNEL); |
| if (!esp->command_block) |
| goto fail_unmap_regs_dma; |
| |
| host->irq = err = platform_get_irq(dev, 0); |
| if (err < 0) |
| goto fail_unmap_command_block; |
| err = request_irq(host->irq, scsi_esp_intr, IRQF_SHARED, |
| "SUN3X ESP", esp); |
| if (err < 0) |
| goto fail_unmap_command_block; |
| |
| esp->scsi_id = 7; |
| esp->host->this_id = esp->scsi_id; |
| esp->scsi_id_mask = (1 << esp->scsi_id); |
| esp->cfreq = 20000000; |
| |
| dev_set_drvdata(&dev->dev, esp); |
| |
| err = scsi_esp_register(esp); |
| if (err) |
| goto fail_free_irq; |
| |
| return 0; |
| |
| fail_free_irq: |
| free_irq(host->irq, esp); |
| fail_unmap_command_block: |
| dma_free_coherent(esp->dev, 16, |
| esp->command_block, |
| esp->command_block_dma); |
| fail_unmap_regs_dma: |
| iounmap(esp->dma_regs); |
| fail_unmap_regs: |
| iounmap(esp->regs); |
| fail_unlink: |
| scsi_host_put(host); |
| fail: |
| return err; |
| } |
| |
| static void esp_sun3x_remove(struct platform_device *dev) |
| { |
| struct esp *esp = dev_get_drvdata(&dev->dev); |
| unsigned int irq = esp->host->irq; |
| u32 val; |
| |
| scsi_esp_unregister(esp); |
| |
| /* Disable interrupts. */ |
| val = dma_read32(DMA_CSR); |
| dma_write32(val & ~DMA_INT_ENAB, DMA_CSR); |
| |
| free_irq(irq, esp); |
| dma_free_coherent(esp->dev, 16, |
| esp->command_block, |
| esp->command_block_dma); |
| |
| scsi_host_put(esp->host); |
| } |
| |
| static struct platform_driver esp_sun3x_driver = { |
| .probe = esp_sun3x_probe, |
| .remove_new = esp_sun3x_remove, |
| .driver = { |
| .name = "sun3x_esp", |
| }, |
| }; |
| module_platform_driver(esp_sun3x_driver); |
| |
| MODULE_DESCRIPTION("Sun3x ESP SCSI driver"); |
| MODULE_AUTHOR("Thomas Bogendoerfer (tsbogend@alpha.franken.de)"); |
| MODULE_LICENSE("GPL"); |
| MODULE_VERSION(DRV_VERSION); |
| MODULE_ALIAS("platform:sun3x_esp"); |