blob: bac63d04297f0740ae4a1ab6889bed1da0d148ef [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2009 - 2019 Broadcom */
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/compiler.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/msi.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/printk.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include "../pci.h"
/* BRCM_PCIE_CAP_REGS - Offset for the mandatory capability config regs */
#define BRCM_PCIE_CAP_REGS 0x00ac
/* Broadcom STB PCIe Register Offsets */
#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1 0x0188
#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK 0xc
#define PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN 0x0
#define PCIE_RC_CFG_PRIV1_ID_VAL3 0x043c
#define PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK 0xffffff
#define PCIE_RC_CFG_PRIV1_LINK_CAPABILITY 0x04dc
#define PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK 0xc00
#define PCIE_RC_DL_MDIO_ADDR 0x1100
#define PCIE_RC_DL_MDIO_WR_DATA 0x1104
#define PCIE_RC_DL_MDIO_RD_DATA 0x1108
#define PCIE_MISC_MISC_CTRL 0x4008
#define PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK 0x1000
#define PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK 0x2000
#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK 0x300000
#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128 0x0
#define PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK 0xf8000000
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO 0x400c
#define PCIE_MEM_WIN0_LO(win) \
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO + ((win) * 8)
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI 0x4010
#define PCIE_MEM_WIN0_HI(win) \
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI + ((win) * 8)
#define PCIE_MISC_RC_BAR1_CONFIG_LO 0x402c
#define PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK 0x1f
#define PCIE_MISC_RC_BAR2_CONFIG_LO 0x4034
#define PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK 0x1f
#define PCIE_MISC_RC_BAR2_CONFIG_HI 0x4038
#define PCIE_MISC_RC_BAR3_CONFIG_LO 0x403c
#define PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK 0x1f
#define PCIE_MISC_MSI_BAR_CONFIG_LO 0x4044
#define PCIE_MISC_MSI_BAR_CONFIG_HI 0x4048
#define PCIE_MISC_MSI_DATA_CONFIG 0x404c
#define PCIE_MISC_MSI_DATA_CONFIG_VAL 0xffe06540
#define PCIE_MISC_PCIE_CTRL 0x4064
#define PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK 0x1
#define PCIE_MISC_PCIE_STATUS 0x4068
#define PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK 0x80
#define PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK 0x20
#define PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK 0x10
#define PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK 0x40
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT 0x4070
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK 0xfff00000
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK 0xfff0
#define PCIE_MEM_WIN0_BASE_LIMIT(win) \
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT + ((win) * 4)
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI 0x4080
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK 0xff
#define PCIE_MEM_WIN0_BASE_HI(win) \
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI + ((win) * 8)
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI 0x4084
#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK 0xff
#define PCIE_MEM_WIN0_LIMIT_HI(win) \
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI + ((win) * 8)
#define PCIE_MISC_HARD_PCIE_HARD_DEBUG 0x4204
#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK 0x2
#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK 0x08000000
#define PCIE_MSI_INTR2_STATUS 0x4500
#define PCIE_MSI_INTR2_CLR 0x4508
#define PCIE_MSI_INTR2_MASK_SET 0x4510
#define PCIE_MSI_INTR2_MASK_CLR 0x4514
#define PCIE_EXT_CFG_DATA 0x8000
#define PCIE_EXT_CFG_INDEX 0x9000
#define PCIE_EXT_BUSNUM_SHIFT 20
#define PCIE_EXT_SLOT_SHIFT 15
#define PCIE_EXT_FUNC_SHIFT 12
#define PCIE_RGR1_SW_INIT_1 0x9210
#define PCIE_RGR1_SW_INIT_1_PERST_MASK 0x1
#define PCIE_RGR1_SW_INIT_1_INIT_MASK 0x2
/* PCIe parameters */
#define BRCM_NUM_PCIE_OUT_WINS 0x4
#define BRCM_INT_PCI_MSI_NR 32
/* MSI target adresses */
#define BRCM_MSI_TARGET_ADDR_LT_4GB 0x0fffffffcULL
#define BRCM_MSI_TARGET_ADDR_GT_4GB 0xffffffffcULL
/* MDIO registers */
#define MDIO_PORT0 0x0
#define MDIO_DATA_MASK 0x7fffffff
#define MDIO_PORT_MASK 0xf0000
#define MDIO_REGAD_MASK 0xffff
#define MDIO_CMD_MASK 0xfff00000
#define MDIO_CMD_READ 0x1
#define MDIO_CMD_WRITE 0x0
#define MDIO_DATA_DONE_MASK 0x80000000
#define MDIO_RD_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 1 : 0)
#define MDIO_WT_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 0 : 1)
#define SSC_REGS_ADDR 0x1100
#define SET_ADDR_OFFSET 0x1f
#define SSC_CNTL_OFFSET 0x2
#define SSC_CNTL_OVRD_EN_MASK 0x8000
#define SSC_CNTL_OVRD_VAL_MASK 0x4000
#define SSC_STATUS_OFFSET 0x1
#define SSC_STATUS_SSC_MASK 0x400
#define SSC_STATUS_PLL_LOCK_MASK 0x800
struct brcm_msi {
struct device *dev;
void __iomem *base;
struct device_node *np;
struct irq_domain *msi_domain;
struct irq_domain *inner_domain;
struct mutex lock; /* guards the alloc/free operations */
u64 target_addr;
int irq;
/* used indicates which MSI interrupts have been alloc'd */
unsigned long used;
};
/* Internal PCIe Host Controller Information.*/
struct brcm_pcie {
struct device *dev;
void __iomem *base;
struct clk *clk;
struct device_node *np;
bool ssc;
int gen;
u64 msi_target_addr;
struct brcm_msi *msi;
};
/*
* This is to convert the size of the inbound "BAR" region to the
* non-linear values of PCIE_X_MISC_RC_BAR[123]_CONFIG_LO.SIZE
*/
static int brcm_pcie_encode_ibar_size(u64 size)
{
int log2_in = ilog2(size);
if (log2_in >= 12 && log2_in <= 15)
/* Covers 4KB to 32KB (inclusive) */
return (log2_in - 12) + 0x1c;
else if (log2_in >= 16 && log2_in <= 35)
/* Covers 64KB to 32GB, (inclusive) */
return log2_in - 15;
/* Something is awry so disable */
return 0;
}
static u32 brcm_pcie_mdio_form_pkt(int port, int regad, int cmd)
{
u32 pkt = 0;
pkt |= FIELD_PREP(MDIO_PORT_MASK, port);
pkt |= FIELD_PREP(MDIO_REGAD_MASK, regad);
pkt |= FIELD_PREP(MDIO_CMD_MASK, cmd);
return pkt;
}
/* negative return value indicates error */
static int brcm_pcie_mdio_read(void __iomem *base, u8 port, u8 regad, u32 *val)
{
int tries;
u32 data;
writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_READ),
base + PCIE_RC_DL_MDIO_ADDR);
readl(base + PCIE_RC_DL_MDIO_ADDR);
data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
for (tries = 0; !MDIO_RD_DONE(data) && tries < 10; tries++) {
udelay(10);
data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
}
*val = FIELD_GET(MDIO_DATA_MASK, data);
return MDIO_RD_DONE(data) ? 0 : -EIO;
}
/* negative return value indicates error */
static int brcm_pcie_mdio_write(void __iomem *base, u8 port,
u8 regad, u16 wrdata)
{
int tries;
u32 data;
writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_WRITE),
base + PCIE_RC_DL_MDIO_ADDR);
readl(base + PCIE_RC_DL_MDIO_ADDR);
writel(MDIO_DATA_DONE_MASK | wrdata, base + PCIE_RC_DL_MDIO_WR_DATA);
data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
for (tries = 0; !MDIO_WT_DONE(data) && tries < 10; tries++) {
udelay(10);
data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
}
return MDIO_WT_DONE(data) ? 0 : -EIO;
}
/*
* Configures device for Spread Spectrum Clocking (SSC) mode; a negative
* return value indicates error.
*/
static int brcm_pcie_set_ssc(struct brcm_pcie *pcie)
{
int pll, ssc;
int ret;
u32 tmp;
ret = brcm_pcie_mdio_write(pcie->base, MDIO_PORT0, SET_ADDR_OFFSET,
SSC_REGS_ADDR);
if (ret < 0)
return ret;
ret = brcm_pcie_mdio_read(pcie->base, MDIO_PORT0,
SSC_CNTL_OFFSET, &tmp);
if (ret < 0)
return ret;
u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_EN_MASK);
u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_VAL_MASK);
ret = brcm_pcie_mdio_write(pcie->base, MDIO_PORT0,
SSC_CNTL_OFFSET, tmp);
if (ret < 0)
return ret;
usleep_range(1000, 2000);
ret = brcm_pcie_mdio_read(pcie->base, MDIO_PORT0,
SSC_STATUS_OFFSET, &tmp);
if (ret < 0)
return ret;
ssc = FIELD_GET(SSC_STATUS_SSC_MASK, tmp);
pll = FIELD_GET(SSC_STATUS_PLL_LOCK_MASK, tmp);
return ssc && pll ? 0 : -EIO;
}
/* Limits operation to a specific generation (1, 2, or 3) */
static void brcm_pcie_set_gen(struct brcm_pcie *pcie, int gen)
{
u16 lnkctl2 = readw(pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
u32 lnkcap = readl(pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
lnkcap = (lnkcap & ~PCI_EXP_LNKCAP_SLS) | gen;
writel(lnkcap, pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
lnkctl2 = (lnkctl2 & ~0xf) | gen;
writew(lnkctl2, pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
}
static void brcm_pcie_set_outbound_win(struct brcm_pcie *pcie,
unsigned int win, u64 cpu_addr,
u64 pcie_addr, u64 size)
{
u32 cpu_addr_mb_high, limit_addr_mb_high;
phys_addr_t cpu_addr_mb, limit_addr_mb;
int high_addr_shift;
u32 tmp;
/* Set the base of the pcie_addr window */
writel(lower_32_bits(pcie_addr), pcie->base + PCIE_MEM_WIN0_LO(win));
writel(upper_32_bits(pcie_addr), pcie->base + PCIE_MEM_WIN0_HI(win));
/* Write the addr base & limit lower bits (in MBs) */
cpu_addr_mb = cpu_addr / SZ_1M;
limit_addr_mb = (cpu_addr + size - 1) / SZ_1M;
tmp = readl(pcie->base + PCIE_MEM_WIN0_BASE_LIMIT(win));
u32p_replace_bits(&tmp, cpu_addr_mb,
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK);
u32p_replace_bits(&tmp, limit_addr_mb,
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK);
writel(tmp, pcie->base + PCIE_MEM_WIN0_BASE_LIMIT(win));
/* Write the cpu & limit addr upper bits */
high_addr_shift =
HWEIGHT32(PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK);
cpu_addr_mb_high = cpu_addr_mb >> high_addr_shift;
tmp = readl(pcie->base + PCIE_MEM_WIN0_BASE_HI(win));
u32p_replace_bits(&tmp, cpu_addr_mb_high,
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK);
writel(tmp, pcie->base + PCIE_MEM_WIN0_BASE_HI(win));
limit_addr_mb_high = limit_addr_mb >> high_addr_shift;
tmp = readl(pcie->base + PCIE_MEM_WIN0_LIMIT_HI(win));
u32p_replace_bits(&tmp, limit_addr_mb_high,
PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK);
writel(tmp, pcie->base + PCIE_MEM_WIN0_LIMIT_HI(win));
}
static struct irq_chip brcm_msi_irq_chip = {
.name = "BRCM STB PCIe MSI",
.irq_ack = irq_chip_ack_parent,
.irq_mask = pci_msi_mask_irq,
.irq_unmask = pci_msi_unmask_irq,
};
static struct msi_domain_info brcm_msi_domain_info = {
/* Multi MSI is supported by the controller, but not by this driver */
.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
.chip = &brcm_msi_irq_chip,
};
static void brcm_pcie_msi_isr(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned long status, virq;
struct brcm_msi *msi;
struct device *dev;
u32 bit;
chained_irq_enter(chip, desc);
msi = irq_desc_get_handler_data(desc);
dev = msi->dev;
status = readl(msi->base + PCIE_MSI_INTR2_STATUS);
for_each_set_bit(bit, &status, BRCM_INT_PCI_MSI_NR) {
virq = irq_find_mapping(msi->inner_domain, bit);
if (virq)
generic_handle_irq(virq);
else
dev_dbg(dev, "unexpected MSI\n");
}
chained_irq_exit(chip, desc);
}
static void brcm_msi_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
struct brcm_msi *msi = irq_data_get_irq_chip_data(data);
msg->address_lo = lower_32_bits(msi->target_addr);
msg->address_hi = upper_32_bits(msi->target_addr);
msg->data = (0xffff & PCIE_MISC_MSI_DATA_CONFIG_VAL) | data->hwirq;
}
static int brcm_msi_set_affinity(struct irq_data *irq_data,
const struct cpumask *mask, bool force)
{
return -EINVAL;
}
static void brcm_msi_ack_irq(struct irq_data *data)
{
struct brcm_msi *msi = irq_data_get_irq_chip_data(data);
writel(1 << data->hwirq, msi->base + PCIE_MSI_INTR2_CLR);
}
static struct irq_chip brcm_msi_bottom_irq_chip = {
.name = "BRCM STB MSI",
.irq_compose_msi_msg = brcm_msi_compose_msi_msg,
.irq_set_affinity = brcm_msi_set_affinity,
.irq_ack = brcm_msi_ack_irq,
};
static int brcm_msi_alloc(struct brcm_msi *msi)
{
int hwirq;
mutex_lock(&msi->lock);
hwirq = bitmap_find_free_region(&msi->used, BRCM_INT_PCI_MSI_NR, 0);
mutex_unlock(&msi->lock);
return hwirq;
}
static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq)
{
mutex_lock(&msi->lock);
bitmap_release_region(&msi->used, hwirq, 0);
mutex_unlock(&msi->lock);
}
static int brcm_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *args)
{
struct brcm_msi *msi = domain->host_data;
int hwirq;
hwirq = brcm_msi_alloc(msi);
if (hwirq < 0)
return hwirq;
irq_domain_set_info(domain, virq, (irq_hw_number_t)hwirq,
&brcm_msi_bottom_irq_chip, domain->host_data,
handle_edge_irq, NULL, NULL);
return 0;
}
static void brcm_irq_domain_free(struct irq_domain *domain,
unsigned int virq, unsigned int nr_irqs)
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct brcm_msi *msi = irq_data_get_irq_chip_data(d);
brcm_msi_free(msi, d->hwirq);
}
static const struct irq_domain_ops msi_domain_ops = {
.alloc = brcm_irq_domain_alloc,
.free = brcm_irq_domain_free,
};
static int brcm_allocate_domains(struct brcm_msi *msi)
{
struct fwnode_handle *fwnode = of_node_to_fwnode(msi->np);
struct device *dev = msi->dev;
msi->inner_domain = irq_domain_add_linear(NULL, BRCM_INT_PCI_MSI_NR,
&msi_domain_ops, msi);
if (!msi->inner_domain) {
dev_err(dev, "failed to create IRQ domain\n");
return -ENOMEM;
}
msi->msi_domain = pci_msi_create_irq_domain(fwnode,
&brcm_msi_domain_info,
msi->inner_domain);
if (!msi->msi_domain) {
dev_err(dev, "failed to create MSI domain\n");
irq_domain_remove(msi->inner_domain);
return -ENOMEM;
}
return 0;
}
static void brcm_free_domains(struct brcm_msi *msi)
{
irq_domain_remove(msi->msi_domain);
irq_domain_remove(msi->inner_domain);
}
static void brcm_msi_remove(struct brcm_pcie *pcie)
{
struct brcm_msi *msi = pcie->msi;
if (!msi)
return;
irq_set_chained_handler(msi->irq, NULL);
irq_set_handler_data(msi->irq, NULL);
brcm_free_domains(msi);
}
static void brcm_msi_set_regs(struct brcm_msi *msi)
{
writel(0xffffffff, msi->base + PCIE_MSI_INTR2_MASK_CLR);
/*
* The 0 bit of PCIE_MISC_MSI_BAR_CONFIG_LO is repurposed to MSI
* enable, which we set to 1.
*/
writel(lower_32_bits(msi->target_addr) | 0x1,
msi->base + PCIE_MISC_MSI_BAR_CONFIG_LO);
writel(upper_32_bits(msi->target_addr),
msi->base + PCIE_MISC_MSI_BAR_CONFIG_HI);
writel(PCIE_MISC_MSI_DATA_CONFIG_VAL,
msi->base + PCIE_MISC_MSI_DATA_CONFIG);
}
static int brcm_pcie_enable_msi(struct brcm_pcie *pcie)
{
struct brcm_msi *msi;
int irq, ret;
struct device *dev = pcie->dev;
irq = irq_of_parse_and_map(dev->of_node, 1);
if (irq <= 0) {
dev_err(dev, "cannot map MSI interrupt\n");
return -ENODEV;
}
msi = devm_kzalloc(dev, sizeof(struct brcm_msi), GFP_KERNEL);
if (!msi)
return -ENOMEM;
mutex_init(&msi->lock);
msi->dev = dev;
msi->base = pcie->base;
msi->np = pcie->np;
msi->target_addr = pcie->msi_target_addr;
msi->irq = irq;
ret = brcm_allocate_domains(msi);
if (ret)
return ret;
irq_set_chained_handler_and_data(msi->irq, brcm_pcie_msi_isr, msi);
brcm_msi_set_regs(msi);
pcie->msi = msi;
return 0;
}
/* The controller is capable of serving in both RC and EP roles */
static bool brcm_pcie_rc_mode(struct brcm_pcie *pcie)
{
void __iomem *base = pcie->base;
u32 val = readl(base + PCIE_MISC_PCIE_STATUS);
return !!FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK, val);
}
static bool brcm_pcie_link_up(struct brcm_pcie *pcie)
{
u32 val = readl(pcie->base + PCIE_MISC_PCIE_STATUS);
u32 dla = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK, val);
u32 plu = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK, val);
return dla && plu;
}
/* Configuration space read/write support */
static inline int brcm_pcie_cfg_index(int busnr, int devfn, int reg)
{
return ((PCI_SLOT(devfn) & 0x1f) << PCIE_EXT_SLOT_SHIFT)
| ((PCI_FUNC(devfn) & 0x07) << PCIE_EXT_FUNC_SHIFT)
| (busnr << PCIE_EXT_BUSNUM_SHIFT)
| (reg & ~3);
}
static void __iomem *brcm_pcie_map_conf(struct pci_bus *bus, unsigned int devfn,
int where)
{
struct brcm_pcie *pcie = bus->sysdata;
void __iomem *base = pcie->base;
int idx;
/* Accesses to the RC go right to the RC registers if slot==0 */
if (pci_is_root_bus(bus))
return PCI_SLOT(devfn) ? NULL : base + where;
/* For devices, write to the config space index register */
idx = brcm_pcie_cfg_index(bus->number, devfn, 0);
writel(idx, pcie->base + PCIE_EXT_CFG_INDEX);
return base + PCIE_EXT_CFG_DATA + where;
}
static struct pci_ops brcm_pcie_ops = {
.map_bus = brcm_pcie_map_conf,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
static inline void brcm_pcie_bridge_sw_init_set(struct brcm_pcie *pcie, u32 val)
{
u32 tmp;
tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_INIT_MASK);
writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
}
static inline void brcm_pcie_perst_set(struct brcm_pcie *pcie, u32 val)
{
u32 tmp;
tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_PERST_MASK);
writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
}
static inline int brcm_pcie_get_rc_bar2_size_and_offset(struct brcm_pcie *pcie,
u64 *rc_bar2_size,
u64 *rc_bar2_offset)
{
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
struct device *dev = pcie->dev;
struct resource_entry *entry;
entry = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);
if (!entry)
return -ENODEV;
/*
* The controller expects the inbound window offset to be calculated as
* the difference between PCIe's address space and CPU's. The offset
* provided by the firmware is calculated the opposite way, so we
* negate it.
*/
*rc_bar2_offset = -entry->offset;
*rc_bar2_size = 1ULL << fls64(entry->res->end - entry->res->start);
/*
* We validate the inbound memory view even though we should trust
* whatever the device-tree provides. This is because of an HW issue on
* early Raspberry Pi 4's revisions (bcm2711). It turns out its
* firmware has to dynamically edit dma-ranges due to a bug on the
* PCIe controller integration, which prohibits any access above the
* lower 3GB of memory. Given this, we decided to keep the dma-ranges
* in check, avoiding hard to debug device-tree related issues in the
* future:
*
* The PCIe host controller by design must set the inbound viewport to
* be a contiguous arrangement of all of the system's memory. In
* addition, its size mut be a power of two. To further complicate
* matters, the viewport must start on a pcie-address that is aligned
* on a multiple of its size. If a portion of the viewport does not
* represent system memory -- e.g. 3GB of memory requires a 4GB
* viewport -- we can map the outbound memory in or after 3GB and even
* though the viewport will overlap the outbound memory the controller
* will know to send outbound memory downstream and everything else
* upstream.
*
* For example:
*
* - The best-case scenario, memory up to 3GB, is to place the inbound
* region in the first 4GB of pcie-space, as some legacy devices can
* only address 32bits. We would also like to put the MSI under 4GB
* as well, since some devices require a 32bit MSI target address.
*
* - If the system memory is 4GB or larger we cannot start the inbound
* region at location 0 (since we have to allow some space for
* outbound memory @ 3GB). So instead it will start at the 1x
* multiple of its size
*/
if (!*rc_bar2_size || (*rc_bar2_offset & (*rc_bar2_size - 1)) ||
(*rc_bar2_offset < SZ_4G && *rc_bar2_offset > SZ_2G)) {
dev_err(dev, "Invalid rc_bar2_offset/size: size 0x%llx, off 0x%llx\n",
*rc_bar2_size, *rc_bar2_offset);
return -EINVAL;
}
return 0;
}
static int brcm_pcie_setup(struct brcm_pcie *pcie)
{
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
u64 rc_bar2_offset, rc_bar2_size;
void __iomem *base = pcie->base;
struct device *dev = pcie->dev;
struct resource_entry *entry;
unsigned int scb_size_val;
bool ssc_good = false;
struct resource *res;
int num_out_wins = 0;
u16 nlw, cls, lnksta;
int i, ret;
u32 tmp, aspm_support;
/* Reset the bridge */
brcm_pcie_bridge_sw_init_set(pcie, 1);
brcm_pcie_perst_set(pcie, 1);
usleep_range(100, 200);
/* Take the bridge out of reset */
brcm_pcie_bridge_sw_init_set(pcie, 0);
tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
tmp &= ~PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK;
writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
/* Wait for SerDes to be stable */
usleep_range(100, 200);
/* Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN */
u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK);
u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK);
u32p_replace_bits(&tmp, PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128,
PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK);
writel(tmp, base + PCIE_MISC_MISC_CTRL);
ret = brcm_pcie_get_rc_bar2_size_and_offset(pcie, &rc_bar2_size,
&rc_bar2_offset);
if (ret)
return ret;
tmp = lower_32_bits(rc_bar2_offset);
u32p_replace_bits(&tmp, brcm_pcie_encode_ibar_size(rc_bar2_size),
PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK);
writel(tmp, base + PCIE_MISC_RC_BAR2_CONFIG_LO);
writel(upper_32_bits(rc_bar2_offset),
base + PCIE_MISC_RC_BAR2_CONFIG_HI);
scb_size_val = rc_bar2_size ?
ilog2(rc_bar2_size) - 15 : 0xf; /* 0xf is 1GB */
tmp = readl(base + PCIE_MISC_MISC_CTRL);
u32p_replace_bits(&tmp, scb_size_val,
PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK);
writel(tmp, base + PCIE_MISC_MISC_CTRL);
/*
* We ideally want the MSI target address to be located in the 32bit
* addressable memory area. Some devices might depend on it. This is
* possible either when the inbound window is located above the lower
* 4GB or when the inbound area is smaller than 4GB (taking into
* account the rounding-up we're forced to perform).
*/
if (rc_bar2_offset >= SZ_4G || (rc_bar2_size + rc_bar2_offset) < SZ_4G)
pcie->msi_target_addr = BRCM_MSI_TARGET_ADDR_LT_4GB;
else
pcie->msi_target_addr = BRCM_MSI_TARGET_ADDR_GT_4GB;
/* disable the PCIe->GISB memory window (RC_BAR1) */
tmp = readl(base + PCIE_MISC_RC_BAR1_CONFIG_LO);
tmp &= ~PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK;
writel(tmp, base + PCIE_MISC_RC_BAR1_CONFIG_LO);
/* disable the PCIe->SCB memory window (RC_BAR3) */
tmp = readl(base + PCIE_MISC_RC_BAR3_CONFIG_LO);
tmp &= ~PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK;
writel(tmp, base + PCIE_MISC_RC_BAR3_CONFIG_LO);
/* Mask all interrupts since we are not handling any yet */
writel(0xffffffff, pcie->base + PCIE_MSI_INTR2_MASK_SET);
/* clear any interrupts we find on boot */
writel(0xffffffff, pcie->base + PCIE_MSI_INTR2_CLR);
if (pcie->gen)
brcm_pcie_set_gen(pcie, pcie->gen);
/* Unassert the fundamental reset */
brcm_pcie_perst_set(pcie, 0);
/*
* Give the RC/EP time to wake up, before trying to configure RC.
* Intermittently check status for link-up, up to a total of 100ms.
*/
for (i = 0; i < 100 && !brcm_pcie_link_up(pcie); i += 5)
msleep(5);
if (!brcm_pcie_link_up(pcie)) {
dev_err(dev, "link down\n");
return -ENODEV;
}
if (!brcm_pcie_rc_mode(pcie)) {
dev_err(dev, "PCIe misconfigured; is in EP mode\n");
return -EINVAL;
}
resource_list_for_each_entry(entry, &bridge->windows) {
res = entry->res;
if (resource_type(res) != IORESOURCE_MEM)
continue;
if (num_out_wins >= BRCM_NUM_PCIE_OUT_WINS) {
dev_err(pcie->dev, "too many outbound wins\n");
return -EINVAL;
}
brcm_pcie_set_outbound_win(pcie, num_out_wins, res->start,
res->start - entry->offset,
resource_size(res));
num_out_wins++;
}
/* Don't advertise L0s capability if 'aspm-no-l0s' */
aspm_support = PCIE_LINK_STATE_L1;
if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
aspm_support |= PCIE_LINK_STATE_L0S;
tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
u32p_replace_bits(&tmp, aspm_support,
PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
/*
* For config space accesses on the RC, show the right class for
* a PCIe-PCIe bridge (the default setting is to be EP mode).
*/
tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
u32p_replace_bits(&tmp, 0x060400,
PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
if (pcie->ssc) {
ret = brcm_pcie_set_ssc(pcie);
if (ret == 0)
ssc_good = true;
else
dev_err(dev, "failed attempt to enter ssc mode\n");
}
lnksta = readw(base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKSTA);
cls = FIELD_GET(PCI_EXP_LNKSTA_CLS, lnksta);
nlw = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta);
dev_info(dev, "link up, %s x%u %s\n",
pci_speed_string(pcie_link_speed[cls]), nlw,
ssc_good ? "(SSC)" : "(!SSC)");
/* PCIe->SCB endian mode for BAR */
tmp = readl(base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
u32p_replace_bits(&tmp, PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN,
PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK);
writel(tmp, base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
/*
* Refclk from RC should be gated with CLKREQ# input when ASPM L0s,L1
* is enabled => setting the CLKREQ_DEBUG_ENABLE field to 1.
*/
tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK;
writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
return 0;
}
/* L23 is a low-power PCIe link state */
static void brcm_pcie_enter_l23(struct brcm_pcie *pcie)
{
void __iomem *base = pcie->base;
int l23, i;
u32 tmp;
/* Assert request for L23 */
tmp = readl(base + PCIE_MISC_PCIE_CTRL);
u32p_replace_bits(&tmp, 1, PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK);
writel(tmp, base + PCIE_MISC_PCIE_CTRL);
/* Wait up to 36 msec for L23 */
tmp = readl(base + PCIE_MISC_PCIE_STATUS);
l23 = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK, tmp);
for (i = 0; i < 15 && !l23; i++) {
usleep_range(2000, 2400);
tmp = readl(base + PCIE_MISC_PCIE_STATUS);
l23 = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK,
tmp);
}
if (!l23)
dev_err(pcie->dev, "failed to enter low-power link state\n");
}
static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
{
void __iomem *base = pcie->base;
int tmp;
if (brcm_pcie_link_up(pcie))
brcm_pcie_enter_l23(pcie);
/* Assert fundamental reset */
brcm_pcie_perst_set(pcie, 1);
/* Deassert request for L23 in case it was asserted */
tmp = readl(base + PCIE_MISC_PCIE_CTRL);
u32p_replace_bits(&tmp, 0, PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK);
writel(tmp, base + PCIE_MISC_PCIE_CTRL);
/* Turn off SerDes */
tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
u32p_replace_bits(&tmp, 1, PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
/* Shutdown PCIe bridge */
brcm_pcie_bridge_sw_init_set(pcie, 1);
}
static void __brcm_pcie_remove(struct brcm_pcie *pcie)
{
brcm_msi_remove(pcie);
brcm_pcie_turn_off(pcie);
clk_disable_unprepare(pcie->clk);
}
static int brcm_pcie_remove(struct platform_device *pdev)
{
struct brcm_pcie *pcie = platform_get_drvdata(pdev);
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
pci_stop_root_bus(bridge->bus);
pci_remove_root_bus(bridge->bus);
__brcm_pcie_remove(pcie);
return 0;
}
static int brcm_pcie_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node, *msi_np;
struct pci_host_bridge *bridge;
struct brcm_pcie *pcie;
int ret;
bridge = devm_pci_alloc_host_bridge(&pdev->dev, sizeof(*pcie));
if (!bridge)
return -ENOMEM;
pcie = pci_host_bridge_priv(bridge);
pcie->dev = &pdev->dev;
pcie->np = np;
pcie->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(pcie->base))
return PTR_ERR(pcie->base);
pcie->clk = devm_clk_get_optional(&pdev->dev, "sw_pcie");
if (IS_ERR(pcie->clk))
return PTR_ERR(pcie->clk);
ret = of_pci_get_max_link_speed(np);
pcie->gen = (ret < 0) ? 0 : ret;
pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc");
ret = clk_prepare_enable(pcie->clk);
if (ret) {
dev_err(&pdev->dev, "could not enable clock\n");
return ret;
}
ret = brcm_pcie_setup(pcie);
if (ret)
goto fail;
msi_np = of_parse_phandle(pcie->np, "msi-parent", 0);
if (pci_msi_enabled() && msi_np == pcie->np) {
ret = brcm_pcie_enable_msi(pcie);
if (ret) {
dev_err(pcie->dev, "probe of internal MSI failed");
goto fail;
}
}
bridge->ops = &brcm_pcie_ops;
bridge->sysdata = pcie;
platform_set_drvdata(pdev, pcie);
return pci_host_probe(bridge);
fail:
__brcm_pcie_remove(pcie);
return ret;
}
static const struct of_device_id brcm_pcie_match[] = {
{ .compatible = "brcm,bcm2711-pcie" },
{},
};
MODULE_DEVICE_TABLE(of, brcm_pcie_match);
static struct platform_driver brcm_pcie_driver = {
.probe = brcm_pcie_probe,
.remove = brcm_pcie_remove,
.driver = {
.name = "brcm-pcie",
.of_match_table = brcm_pcie_match,
},
};
module_platform_driver(brcm_pcie_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Broadcom STB PCIe RC driver");
MODULE_AUTHOR("Broadcom");