diff options
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/controller/Kconfig | 1 | ||||
| -rw-r--r-- | drivers/pci/controller/pcie-brcmstb.c | 262 |
2 files changed, 262 insertions, 1 deletions
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig index 27504f108ee5..918e283bbff1 100644 --- a/drivers/pci/controller/Kconfig +++ b/drivers/pci/controller/Kconfig @@ -257,6 +257,7 @@ config PCIE_BRCMSTB tristate "Broadcom Brcmstb PCIe host controller" depends on ARCH_BCM2835 || COMPILE_TEST depends on OF + depends on PCI_MSI_IRQ_DOMAIN help Say Y here to enable PCIe host controller support for Broadcom STB based SoCs, like the Raspberry Pi 4. diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c index 3250a2e6b1b4..d20aabc26273 100644 --- a/drivers/pci/controller/pcie-brcmstb.c +++ b/drivers/pci/controller/pcie-brcmstb.c @@ -2,6 +2,7 @@ /* 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> @@ -9,11 +10,13 @@ #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> @@ -67,6 +70,12 @@ #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 @@ -114,6 +123,11 @@ /* 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 @@ -135,6 +149,19 @@ #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; @@ -144,6 +171,8 @@ struct brcm_pcie { struct device_node *np; bool ssc; int gen; + u64 msi_target_addr; + struct brcm_msi *msi; }; /* @@ -309,6 +338,215 @@ static void brcm_pcie_set_outbound_win(struct brcm_pcie *pcie, 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) { @@ -497,6 +735,18 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie) 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; @@ -646,6 +896,7 @@ static void brcm_pcie_turn_off(struct brcm_pcie *pcie) 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); @@ -664,7 +915,7 @@ static int brcm_pcie_remove(struct platform_device *pdev) static int brcm_pcie_probe(struct platform_device *pdev) { - struct device_node *np = pdev->dev.of_node; + struct device_node *np = pdev->dev.of_node, *msi_np; struct pci_host_bridge *bridge; struct brcm_pcie *pcie; struct pci_bus *child; @@ -708,6 +959,15 @@ static int brcm_pcie_probe(struct platform_device *pdev) 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; |