diff options
| -rw-r--r-- | drivers/pci/host/pcie-rcar.c | 242 |
1 files changed, 241 insertions, 1 deletions
diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c index 3c524b9e60e5..8e06124aa80f 100644 --- a/drivers/pci/host/pcie-rcar.c +++ b/drivers/pci/host/pcie-rcar.c @@ -15,8 +15,11 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/msi.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/of_pci.h> @@ -35,6 +38,7 @@ #define PCIECDR 0x000020 #define PCIEMSR 0x000028 #define PCIEINTXR 0x000400 +#define PCIEMSITXR 0x000840 /* Transfer control */ #define PCIETCTLR 0x02000 @@ -43,6 +47,11 @@ #define DATA_LINK_ACTIVE 1 #define PCIEERRFR 0x02020 #define UNSUPPORTED_REQUEST (1 << 4) +#define PCIEMSIFR 0x02044 +#define PCIEMSIALR 0x02048 +#define MSIFE 1 +#define PCIEMSIAUR 0x0204c +#define PCIEMSIIER 0x02050 /* root port address */ #define PCIEPRAR(x) (0x02080 + ((x) * 0x4)) @@ -85,6 +94,8 @@ #define H1_PCIEPHYDOUTR 0x040014 #define H1_PCIEPHYSR 0x040018 +#define INT_PCI_MSI_NR 32 + #define RCONF(x) (PCICONF(0)+(x)) #define RPMCAP(x) (PMCAP(0)+(x)) #define REXPCAP(x) (EXPCAP(0)+(x)) @@ -97,6 +108,21 @@ #define PCI_MAX_RESOURCES 4 #define MAX_NR_INBOUND_MAPS 6 +struct rcar_msi { + DECLARE_BITMAP(used, INT_PCI_MSI_NR); + struct irq_domain *domain; + struct msi_chip chip; + unsigned long pages; + struct mutex lock; + int irq1; + int irq2; +}; + +static inline struct rcar_msi *to_rcar_msi(struct msi_chip *chip) +{ + return container_of(chip, struct rcar_msi, chip); +} + /* Structure representing the PCIe interface */ struct rcar_pcie { struct device *dev; @@ -106,6 +132,7 @@ struct rcar_pcie { int root_bus_nr; struct clk *clk; struct clk *bus_clk; + struct rcar_msi msi; }; static inline struct rcar_pcie *sys_to_pcie(struct pci_sys_data *sys) @@ -356,10 +383,20 @@ static int rcar_pcie_setup(int nr, struct pci_sys_data *sys) return 1; } +static void rcar_pcie_add_bus(struct pci_bus *bus) +{ + if (IS_ENABLED(CONFIG_PCI_MSI)) { + struct rcar_pcie *pcie = sys_to_pcie(bus->sysdata); + + bus->msi = &pcie->msi.chip; + } +} + struct hw_pci rcar_pci = { .setup = rcar_pcie_setup, .map_irq = of_irq_parse_and_map_pci, .ops = &rcar_pcie_ops, + .add_bus = rcar_pcie_add_bus, }; static void rcar_pcie_enable(struct rcar_pcie *pcie) @@ -477,6 +514,10 @@ static int rcar_pcie_hw_init(struct rcar_pcie *pcie) /* Enable MAC data scrambling. */ rcar_rmw32(pcie, MACCTLR, SCRAMBLE_DISABLE, 0); + /* Enable MSI */ + if (IS_ENABLED(CONFIG_PCI_MSI)) + pci_write_reg(pcie, 0x101f0000, PCIEMSITXR); + /* Finish initialization - establish a PCI Express link */ pci_write_reg(pcie, CFINIT, PCIETCTLR); @@ -530,11 +571,184 @@ static int rcar_pcie_hw_init_h1(struct rcar_pcie *pcie) return -ETIMEDOUT; } +static int rcar_msi_alloc(struct rcar_msi *chip) +{ + int msi; + + mutex_lock(&chip->lock); + + msi = find_first_zero_bit(chip->used, INT_PCI_MSI_NR); + if (msi < INT_PCI_MSI_NR) + set_bit(msi, chip->used); + else + msi = -ENOSPC; + + mutex_unlock(&chip->lock); + + return msi; +} + +static void rcar_msi_free(struct rcar_msi *chip, unsigned long irq) +{ + mutex_lock(&chip->lock); + clear_bit(irq, chip->used); + mutex_unlock(&chip->lock); +} + +static irqreturn_t rcar_pcie_msi_irq(int irq, void *data) +{ + struct rcar_pcie *pcie = data; + struct rcar_msi *msi = &pcie->msi; + unsigned long reg; + + reg = pci_read_reg(pcie, PCIEMSIFR); + + /* MSI & INTx share an interrupt - we only handle MSI here */ + if (!reg) + return IRQ_NONE; + + while (reg) { + unsigned int index = find_first_bit(®, 32); + unsigned int irq; + + /* clear the interrupt */ + pci_write_reg(pcie, 1 << index, PCIEMSIFR); + + irq = irq_find_mapping(msi->domain, index); + if (irq) { + if (test_bit(index, msi->used)) + generic_handle_irq(irq); + else + dev_info(pcie->dev, "unhandled MSI\n"); + } else { + /* Unknown MSI, just clear it */ + dev_dbg(pcie->dev, "unexpected MSI\n"); + } + + /* see if there's any more pending in this vector */ + reg = pci_read_reg(pcie, PCIEMSIFR); + } + + return IRQ_HANDLED; +} + +static int rcar_msi_setup_irq(struct msi_chip *chip, struct pci_dev *pdev, + struct msi_desc *desc) +{ + struct rcar_msi *msi = to_rcar_msi(chip); + struct rcar_pcie *pcie = container_of(chip, struct rcar_pcie, msi.chip); + struct msi_msg msg; + unsigned int irq; + int hwirq; + + hwirq = rcar_msi_alloc(msi); + if (hwirq < 0) + return hwirq; + + irq = irq_create_mapping(msi->domain, hwirq); + if (!irq) { + rcar_msi_free(msi, hwirq); + return -EINVAL; + } + + irq_set_msi_desc(irq, desc); + + msg.address_lo = pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE; + msg.address_hi = pci_read_reg(pcie, PCIEMSIAUR); + msg.data = hwirq; + + write_msi_msg(irq, &msg); + + return 0; +} + +static void rcar_msi_teardown_irq(struct msi_chip *chip, unsigned int irq) +{ + struct rcar_msi *msi = to_rcar_msi(chip); + struct irq_data *d = irq_get_irq_data(irq); + + rcar_msi_free(msi, d->hwirq); +} + +static struct irq_chip rcar_msi_irq_chip = { + .name = "R-Car PCIe MSI", + .irq_enable = unmask_msi_irq, + .irq_disable = mask_msi_irq, + .irq_mask = mask_msi_irq, + .irq_unmask = unmask_msi_irq, +}; + +static int rcar_msi_map(struct irq_domain *domain, unsigned int irq, + irq_hw_number_t hwirq) +{ + irq_set_chip_and_handler(irq, &rcar_msi_irq_chip, handle_simple_irq); + irq_set_chip_data(irq, domain->host_data); + set_irq_flags(irq, IRQF_VALID); + + return 0; +} + +static const struct irq_domain_ops msi_domain_ops = { + .map = rcar_msi_map, +}; + +static int rcar_pcie_enable_msi(struct rcar_pcie *pcie) +{ + struct platform_device *pdev = to_platform_device(pcie->dev); + struct rcar_msi *msi = &pcie->msi; + unsigned long base; + int err; + + mutex_init(&msi->lock); + + msi->chip.dev = pcie->dev; + msi->chip.setup_irq = rcar_msi_setup_irq; + msi->chip.teardown_irq = rcar_msi_teardown_irq; + + msi->domain = irq_domain_add_linear(pcie->dev->of_node, INT_PCI_MSI_NR, + &msi_domain_ops, &msi->chip); + if (!msi->domain) { + dev_err(&pdev->dev, "failed to create IRQ domain\n"); + return -ENOMEM; + } + + /* Two irqs are for MSI, but they are also used for non-MSI irqs */ + err = devm_request_irq(&pdev->dev, msi->irq1, rcar_pcie_msi_irq, + IRQF_SHARED, rcar_msi_irq_chip.name, pcie); + if (err < 0) { + dev_err(&pdev->dev, "failed to request IRQ: %d\n", err); + goto err; + } + + err = devm_request_irq(&pdev->dev, msi->irq2, rcar_pcie_msi_irq, + IRQF_SHARED, rcar_msi_irq_chip.name, pcie); + if (err < 0) { + dev_err(&pdev->dev, "failed to request IRQ: %d\n", err); + goto err; + } + + /* setup MSI data target */ + msi->pages = __get_free_pages(GFP_KERNEL, 0); + base = virt_to_phys((void *)msi->pages); + + pci_write_reg(pcie, base | MSIFE, PCIEMSIALR); + pci_write_reg(pcie, 0, PCIEMSIAUR); + + /* enable all MSI interrupts */ + pci_write_reg(pcie, 0xffffffff, PCIEMSIIER); + + return 0; + +err: + irq_domain_remove(msi->domain); + return err; +} + static int rcar_pcie_get_resources(struct platform_device *pdev, struct rcar_pcie *pcie) { struct resource res; - int err; + int err, i; err = of_address_to_resource(pdev->dev.of_node, 0, &res); if (err) @@ -559,6 +773,22 @@ static int rcar_pcie_get_resources(struct platform_device *pdev, if (err) goto err_map_reg; + i = irq_of_parse_and_map(pdev->dev.of_node, 0); + if (i < 0) { + dev_err(pcie->dev, "cannot get platform resources for msi interrupt\n"); + err = -ENOENT; + goto err_map_reg; + } + pcie->msi.irq1 = i; + + i = irq_of_parse_and_map(pdev->dev.of_node, 1); + if (i < 0) { + dev_err(pcie->dev, "cannot get platform resources for msi interrupt\n"); + err = -ENOENT; + goto err_map_reg; + } + pcie->msi.irq2 = i; + pcie->base = devm_ioremap_resource(&pdev->dev, &res); if (IS_ERR(pcie->base)) { err = PTR_ERR(pcie->base); @@ -732,6 +962,16 @@ static int rcar_pcie_probe(struct platform_device *pdev) if (err) return err; + if (IS_ENABLED(CONFIG_PCI_MSI)) { + err = rcar_pcie_enable_msi(pcie); + if (err < 0) { + dev_err(&pdev->dev, + "failed to enable MSI support: %d\n", + err); + return err; + } + } + of_id = of_match_device(rcar_pcie_of_match, pcie->dev); if (!of_id || !of_id->data) return -EINVAL; |