diff options
Diffstat (limited to 'drivers/pci/controller/pcie-brcmstb.c')
| -rw-r--r-- | drivers/pci/controller/pcie-brcmstb.c | 1015 |
1 files changed, 1015 insertions, 0 deletions
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c new file mode 100644 index 000000000000..d20aabc26273 --- /dev/null +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -0,0 +1,1015 @@ +// 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_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) * 4) + +#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) * 4) + +#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 pci_bus *root_bus; + 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 || + (*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; + + /* Reset the bridge */ + brcm_pcie_bridge_sw_init_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++; + } + + /* + * 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", + PCIE_SPEED2STR(cls + PCI_SPEED_133MHz_PCIX_533), + 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); + clk_put(pcie->clk); +} + +static int brcm_pcie_remove(struct platform_device *pdev) +{ + struct brcm_pcie *pcie = platform_get_drvdata(pdev); + + pci_stop_root_bus(pcie->root_bus); + pci_remove_root_bus(pcie->root_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; + struct pci_bus *child; + struct resource *res; + 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; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pcie->base = devm_ioremap_resource(&pdev->dev, res); + 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 = pci_parse_request_of_pci_ranges(pcie->dev, &bridge->windows, + &bridge->dma_ranges, NULL); + if (ret) + return ret; + + 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->dev.parent = &pdev->dev; + bridge->busnr = 0; + bridge->ops = &brcm_pcie_ops; + bridge->sysdata = pcie; + bridge->map_irq = of_irq_parse_and_map_pci; + bridge->swizzle_irq = pci_common_swizzle; + + ret = pci_scan_root_bus_bridge(bridge); + if (ret < 0) { + dev_err(pcie->dev, "Scanning root bridge failed\n"); + goto fail; + } + + pci_assign_unassigned_bus_resources(bridge->bus); + list_for_each_entry(child, &bridge->bus->children, node) + pcie_bus_configure_settings(child); + pci_bus_add_devices(bridge->bus); + platform_set_drvdata(pdev, pcie); + pcie->root_bus = bridge->bus; + + return 0; +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"); |