From 2c99e55f795593c5f029f65c4b4ab2a72bb076a3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:32 +0100 Subject: [PATCH 01/14] PCI: tegra: Convert to MSI domains In anticipation of the removal of the msi_controller structure, convert the Tegra host controller driver to MSI domains. We end-up with the usual two domain structure, the top one being a generic PCI/MSI domain, the bottom one being Tegra-specific and handling the actual HW interrupt allocation. While at it, convert the normal interrupt handler to a chained handler, handle the controller's MSI IRQ edge triggered, support multiple MSIs per device and use the AFI_MSI_EN_VEC* registers to provide MSI masking. [treding@nvidia.com: fix, clean up and address TODOs from Marc's draft] Link: https://lore.kernel.org/r/20210330151145.997953-2-maz@kernel.org Signed-off-by: Thierry Reding Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/controller/Kconfig | 1 - drivers/pci/controller/pci-tegra.c | 363 ++++++++++++++++------------- 2 files changed, 198 insertions(+), 166 deletions(-) diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig index 5aa8977d7b0f..be8f9ff512a0 100644 --- a/drivers/pci/controller/Kconfig +++ b/drivers/pci/controller/Kconfig @@ -41,7 +41,6 @@ config PCI_TEGRA bool "NVIDIA Tegra PCIe controller" depends on ARCH_TEGRA || COMPILE_TEST depends on PCI_MSI_IRQ_DOMAIN - select PCI_MSI_ARCH_FALLBACKS help Say Y here if you want support for the PCIe host controller found on NVIDIA Tegra SoCs. diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c index 8fcabed7c6a6..8069bd9232d4 100644 --- a/drivers/pci/controller/pci-tegra.c +++ b/drivers/pci/controller/pci-tegra.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -78,23 +79,8 @@ #define AFI_MSI_FPCI_BAR_ST 0x64 #define AFI_MSI_AXI_BAR_ST 0x68 -#define AFI_MSI_VEC0 0x6c -#define AFI_MSI_VEC1 0x70 -#define AFI_MSI_VEC2 0x74 -#define AFI_MSI_VEC3 0x78 -#define AFI_MSI_VEC4 0x7c -#define AFI_MSI_VEC5 0x80 -#define AFI_MSI_VEC6 0x84 -#define AFI_MSI_VEC7 0x88 - -#define AFI_MSI_EN_VEC0 0x8c -#define AFI_MSI_EN_VEC1 0x90 -#define AFI_MSI_EN_VEC2 0x94 -#define AFI_MSI_EN_VEC3 0x98 -#define AFI_MSI_EN_VEC4 0x9c -#define AFI_MSI_EN_VEC5 0xa0 -#define AFI_MSI_EN_VEC6 0xa4 -#define AFI_MSI_EN_VEC7 0xa8 +#define AFI_MSI_VEC(x) (0x6c + ((x) * 4)) +#define AFI_MSI_EN_VEC(x) (0x8c + ((x) * 4)) #define AFI_CONFIGURATION 0xac #define AFI_CONFIGURATION_EN_FPCI (1 << 0) @@ -280,10 +266,10 @@ #define LINK_RETRAIN_TIMEOUT 100000 /* in usec */ struct tegra_msi { - struct msi_controller chip; DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; - struct mutex lock; + struct mutex map_lock; + spinlock_t mask_lock; void *virt; dma_addr_t phys; int irq; @@ -333,11 +319,6 @@ struct tegra_pcie_soc { } ectl; }; -static inline struct tegra_msi *to_tegra_msi(struct msi_controller *chip) -{ - return container_of(chip, struct tegra_msi, chip); -} - struct tegra_pcie { struct device *dev; @@ -372,6 +353,11 @@ struct tegra_pcie { struct dentry *debugfs; }; +static inline struct tegra_pcie *msi_to_pcie(struct tegra_msi *msi) +{ + return container_of(msi, struct tegra_pcie, msi); +} + struct tegra_pcie_port { struct tegra_pcie *pcie; struct device_node *np; @@ -1432,7 +1418,6 @@ static void tegra_pcie_phys_put(struct tegra_pcie *pcie) } } - static int tegra_pcie_get_resources(struct tegra_pcie *pcie) { struct device *dev = pcie->dev; @@ -1509,6 +1494,7 @@ static int tegra_pcie_get_resources(struct tegra_pcie *pcie) phys_put: if (soc->program_uphy) tegra_pcie_phys_put(pcie); + return err; } @@ -1551,161 +1537,227 @@ static void tegra_pcie_pme_turnoff(struct tegra_pcie_port *port) afi_writel(pcie, val, AFI_PCIE_PME); } -static int tegra_msi_alloc(struct tegra_msi *chip) +static void tegra_pcie_msi_irq(struct irq_desc *desc) { - 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 tegra_msi_free(struct tegra_msi *chip, unsigned long irq) -{ - struct device *dev = chip->chip.dev; - - mutex_lock(&chip->lock); - - if (!test_bit(irq, chip->used)) - dev_err(dev, "trying to free unused MSI#%lu\n", irq); - else - clear_bit(irq, chip->used); - - mutex_unlock(&chip->lock); -} - -static irqreturn_t tegra_pcie_msi_irq(int irq, void *data) -{ - struct tegra_pcie *pcie = data; - struct device *dev = pcie->dev; + struct tegra_pcie *pcie = irq_desc_get_handler_data(desc); + struct irq_chip *chip = irq_desc_get_chip(desc); struct tegra_msi *msi = &pcie->msi; - unsigned int i, processed = 0; + struct device *dev = pcie->dev; + unsigned int i; + + chained_irq_enter(chip, desc); for (i = 0; i < 8; i++) { - unsigned long reg = afi_readl(pcie, AFI_MSI_VEC0 + i * 4); + unsigned long reg = afi_readl(pcie, AFI_MSI_VEC(i)); while (reg) { unsigned int offset = find_first_bit(®, 32); unsigned int index = i * 32 + offset; unsigned int irq; - /* clear the interrupt */ - afi_writel(pcie, 1 << offset, AFI_MSI_VEC0 + i * 4); - - irq = irq_find_mapping(msi->domain, index); + irq = irq_find_mapping(msi->domain->parent, index); if (irq) { - if (test_bit(index, msi->used)) - generic_handle_irq(irq); - else - dev_info(dev, "unhandled MSI\n"); + generic_handle_irq(irq); } else { /* * that's weird who triggered this? * just clear it */ dev_info(dev, "unexpected MSI\n"); + afi_writel(pcie, BIT(index % 32), AFI_MSI_VEC(index)); } /* see if there's any more pending in this vector */ - reg = afi_readl(pcie, AFI_MSI_VEC0 + i * 4); - - processed++; + reg = afi_readl(pcie, AFI_MSI_VEC(i)); } } - return processed > 0 ? IRQ_HANDLED : IRQ_NONE; + chained_irq_exit(chip, desc); } -static int tegra_msi_setup_irq(struct msi_controller *chip, - struct pci_dev *pdev, struct msi_desc *desc) +static void tegra_msi_top_irq_ack(struct irq_data *d) { - struct tegra_msi *msi = to_tegra_msi(chip); - struct msi_msg msg; - unsigned int irq; - int hwirq; - - hwirq = tegra_msi_alloc(msi); - if (hwirq < 0) - return hwirq; - - irq = irq_create_mapping(msi->domain, hwirq); - if (!irq) { - tegra_msi_free(msi, hwirq); - return -EINVAL; - } - - irq_set_msi_desc(irq, desc); - - msg.address_lo = lower_32_bits(msi->phys); - msg.address_hi = upper_32_bits(msi->phys); - msg.data = hwirq; - - pci_write_msi_msg(irq, &msg); - - return 0; + irq_chip_ack_parent(d); } -static void tegra_msi_teardown_irq(struct msi_controller *chip, - unsigned int irq) +static void tegra_msi_top_irq_mask(struct irq_data *d) { - struct tegra_msi *msi = to_tegra_msi(chip); - struct irq_data *d = irq_get_irq_data(irq); - irq_hw_number_t hwirq = irqd_to_hwirq(d); - - irq_dispose_mapping(irq); - tegra_msi_free(msi, hwirq); + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); } -static struct irq_chip tegra_msi_irq_chip = { - .name = "Tegra PCIe MSI", - .irq_enable = pci_msi_unmask_irq, - .irq_disable = pci_msi_mask_irq, - .irq_mask = pci_msi_mask_irq, - .irq_unmask = pci_msi_unmask_irq, +static void tegra_msi_top_irq_unmask(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip tegra_msi_top_chip = { + .name = "Tegra PCIe MSI", + .irq_ack = tegra_msi_top_irq_ack, + .irq_mask = tegra_msi_top_irq_mask, + .irq_unmask = tegra_msi_top_irq_unmask, }; -static int tegra_msi_map(struct irq_domain *domain, unsigned int irq, - irq_hw_number_t hwirq) +static void tegra_msi_irq_ack(struct irq_data *d) { - irq_set_chip_and_handler(irq, &tegra_msi_irq_chip, handle_simple_irq); - irq_set_chip_data(irq, domain->host_data); + struct tegra_msi *msi = irq_data_get_irq_chip_data(d); + struct tegra_pcie *pcie = msi_to_pcie(msi); + unsigned int index = d->hwirq / 32; + + /* clear the interrupt */ + afi_writel(pcie, BIT(d->hwirq % 32), AFI_MSI_VEC(index)); +} + +static void tegra_msi_irq_mask(struct irq_data *d) +{ + struct tegra_msi *msi = irq_data_get_irq_chip_data(d); + struct tegra_pcie *pcie = msi_to_pcie(msi); + unsigned int index = d->hwirq / 32; + unsigned long flags; + u32 value; + + spin_lock_irqsave(&msi->mask_lock, flags); + value = afi_readl(pcie, AFI_MSI_EN_VEC(index)); + value &= ~BIT(d->hwirq % 32); + afi_writel(pcie, value, AFI_MSI_EN_VEC(index)); + spin_unlock_irqrestore(&msi->mask_lock, flags); +} + +static void tegra_msi_irq_unmask(struct irq_data *d) +{ + struct tegra_msi *msi = irq_data_get_irq_chip_data(d); + struct tegra_pcie *pcie = msi_to_pcie(msi); + unsigned int index = d->hwirq / 32; + unsigned long flags; + u32 value; + + spin_lock_irqsave(&msi->mask_lock, flags); + value = afi_readl(pcie, AFI_MSI_EN_VEC(index)); + value |= BIT(d->hwirq % 32); + afi_writel(pcie, value, AFI_MSI_EN_VEC(index)); + spin_unlock_irqrestore(&msi->mask_lock, flags); +} + +static int tegra_msi_set_affinity(struct irq_data *d, const struct cpumask *mask, bool force) +{ + return -EINVAL; +} + +static void tegra_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct tegra_msi *msi = irq_data_get_irq_chip_data(data); + + msg->address_lo = lower_32_bits(msi->phys); + msg->address_hi = upper_32_bits(msi->phys); + msg->data = data->hwirq; +} + +static struct irq_chip tegra_msi_bottom_chip = { + .name = "Tegra MSI", + .irq_ack = tegra_msi_irq_ack, + .irq_mask = tegra_msi_irq_mask, + .irq_unmask = tegra_msi_irq_unmask, + .irq_set_affinity = tegra_msi_set_affinity, + .irq_compose_msi_msg = tegra_compose_msi_msg, +}; + +static int tegra_msi_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct tegra_msi *msi = domain->host_data; + unsigned int i; + int hwirq; + + mutex_lock(&msi->map_lock); + + hwirq = bitmap_find_free_region(msi->used, INT_PCI_MSI_NR, order_base_2(nr_irqs)); + + mutex_unlock(&msi->map_lock); + + if (hwirq < 0) + return -ENOSPC; + + for (i = 0; i < nr_irqs; i++) + irq_domain_set_info(domain, virq + i, hwirq + i, + &tegra_msi_bottom_chip, domain->host_data, + handle_edge_irq, NULL, NULL); tegra_cpuidle_pcie_irqs_in_use(); return 0; } -static const struct irq_domain_ops msi_domain_ops = { - .map = tegra_msi_map, +static void tegra_msi_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 tegra_msi *msi = domain->host_data; + + mutex_lock(&msi->map_lock); + + bitmap_release_region(msi->used, d->hwirq, order_base_2(nr_irqs)); + + mutex_unlock(&msi->map_lock); +} + +static const struct irq_domain_ops tegra_msi_domain_ops = { + .alloc = tegra_msi_domain_alloc, + .free = tegra_msi_domain_free, }; +static struct msi_domain_info tegra_msi_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_PCI_MSIX), + .chip = &tegra_msi_top_chip, +}; + +static int tegra_allocate_domains(struct tegra_msi *msi) +{ + struct tegra_pcie *pcie = msi_to_pcie(msi); + struct fwnode_handle *fwnode = dev_fwnode(pcie->dev); + struct irq_domain *parent; + + parent = irq_domain_create_linear(fwnode, INT_PCI_MSI_NR, + &tegra_msi_domain_ops, msi); + if (!parent) { + dev_err(pcie->dev, "failed to create IRQ domain\n"); + return -ENOMEM; + } + irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS); + + msi->domain = pci_msi_create_irq_domain(fwnode, &tegra_msi_info, parent); + if (!msi->domain) { + dev_err(pcie->dev, "failed to create MSI domain\n"); + irq_domain_remove(parent); + return -ENOMEM; + } + + return 0; +} + +static void tegra_free_domains(struct tegra_msi *msi) +{ + struct irq_domain *parent = msi->domain->parent; + + irq_domain_remove(msi->domain); + irq_domain_remove(parent); +} + static int tegra_pcie_msi_setup(struct tegra_pcie *pcie) { - struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie); struct platform_device *pdev = to_platform_device(pcie->dev); struct tegra_msi *msi = &pcie->msi; struct device *dev = pcie->dev; int err; - mutex_init(&msi->lock); + mutex_init(&msi->map_lock); + spin_lock_init(&msi->mask_lock); - msi->chip.dev = dev; - msi->chip.setup_irq = tegra_msi_setup_irq; - msi->chip.teardown_irq = tegra_msi_teardown_irq; - - msi->domain = irq_domain_add_linear(dev->of_node, INT_PCI_MSI_NR, - &msi_domain_ops, &msi->chip); - if (!msi->domain) { - dev_err(dev, "failed to create IRQ domain\n"); - return -ENOMEM; + if (IS_ENABLED(CONFIG_PCI_MSI)) { + err = tegra_allocate_domains(msi); + if (err) + return err; } err = platform_get_irq_byname(pdev, "msi"); @@ -1714,12 +1766,7 @@ static int tegra_pcie_msi_setup(struct tegra_pcie *pcie) msi->irq = err; - err = request_irq(msi->irq, tegra_pcie_msi_irq, IRQF_NO_THREAD, - tegra_msi_irq_chip.name, pcie); - if (err < 0) { - dev_err(dev, "failed to request IRQ: %d\n", err); - goto free_irq_domain; - } + irq_set_chained_handler_and_data(msi->irq, tegra_pcie_msi_irq, pcie); /* Though the PCIe controller can address >32-bit address space, to * facilitate endpoints that support only 32-bit MSI target address, @@ -1740,14 +1787,14 @@ static int tegra_pcie_msi_setup(struct tegra_pcie *pcie) goto free_irq; } - host->msi = &msi->chip; - return 0; free_irq: - free_irq(msi->irq, pcie); + irq_set_chained_handler_and_data(msi->irq, NULL, NULL); free_irq_domain: - irq_domain_remove(msi->domain); + if (IS_ENABLED(CONFIG_PCI_MSI)) + tegra_free_domains(msi); + return err; } @@ -1755,22 +1802,18 @@ static void tegra_pcie_enable_msi(struct tegra_pcie *pcie) { const struct tegra_pcie_soc *soc = pcie->soc; struct tegra_msi *msi = &pcie->msi; - u32 reg; + u32 reg, msi_state[INT_PCI_MSI_NR / 32]; + int i; afi_writel(pcie, msi->phys >> soc->msi_base_shift, AFI_MSI_FPCI_BAR_ST); afi_writel(pcie, msi->phys, AFI_MSI_AXI_BAR_ST); /* this register is in 4K increments */ afi_writel(pcie, 1, AFI_MSI_BAR_SZ); - /* enable all MSI vectors */ - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC0); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC1); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC2); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC3); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC4); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC5); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC6); - afi_writel(pcie, 0xffffffff, AFI_MSI_EN_VEC7); + /* Restore the MSI allocation state */ + bitmap_to_arr32(msi_state, msi->used, INT_PCI_MSI_NR); + for (i = 0; i < ARRAY_SIZE(msi_state); i++) + afi_writel(pcie, msi_state[i], AFI_MSI_EN_VEC(i)); /* and unmask the MSI interrupt */ reg = afi_readl(pcie, AFI_INTR_MASK); @@ -1786,16 +1829,16 @@ static void tegra_pcie_msi_teardown(struct tegra_pcie *pcie) dma_free_attrs(pcie->dev, PAGE_SIZE, msi->virt, msi->phys, DMA_ATTR_NO_KERNEL_MAPPING); - if (msi->irq > 0) - free_irq(msi->irq, pcie); - for (i = 0; i < INT_PCI_MSI_NR; i++) { irq = irq_find_mapping(msi->domain, i); if (irq > 0) - irq_dispose_mapping(irq); + irq_domain_free_irqs(irq, 1); } - irq_domain_remove(msi->domain); + irq_set_chained_handler_and_data(msi->irq, NULL, NULL); + + if (IS_ENABLED(CONFIG_PCI_MSI)) + tegra_free_domains(msi); } static int tegra_pcie_disable_msi(struct tegra_pcie *pcie) @@ -1807,16 +1850,6 @@ static int tegra_pcie_disable_msi(struct tegra_pcie *pcie) value &= ~AFI_INTR_MASK_MSI_MASK; afi_writel(pcie, value, AFI_INTR_MASK); - /* disable all MSI vectors */ - afi_writel(pcie, 0, AFI_MSI_EN_VEC0); - afi_writel(pcie, 0, AFI_MSI_EN_VEC1); - afi_writel(pcie, 0, AFI_MSI_EN_VEC2); - afi_writel(pcie, 0, AFI_MSI_EN_VEC3); - afi_writel(pcie, 0, AFI_MSI_EN_VEC4); - afi_writel(pcie, 0, AFI_MSI_EN_VEC5); - afi_writel(pcie, 0, AFI_MSI_EN_VEC6); - afi_writel(pcie, 0, AFI_MSI_EN_VEC7); - return 0; } From 93cd1bb4862d71298ad5ec86991eac0a119d024d Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:33 +0100 Subject: [PATCH 02/14] PCI: rcar: Don't allocate extra memory for the MSI capture address A long cargo-culted behaviour of PCI drivers is to allocate memory to obtain an address that is fed to the controller as the MSI capture address (i.e. the MSI doorbell). But there is no actual requirement for this address to be RAM. All it needs to be is a suitable aligned address that will *not* be DMA'd to. Since the rcar platform already has a requirement that this address should be in the first 4GB of the physical address space, use the controller's own base address as the capture address. Link: https://lore.kernel.org/r/20210330151145.997953-3-maz@kernel.org Tested-by: Yoshihiro Shimoda Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Reviewed-by: Yoshihiro Shimoda --- drivers/pci/controller/pcie-rcar-host.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index a728e8f9ad3c..ce952403e22c 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -36,7 +36,6 @@ struct rcar_msi { DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; struct msi_controller chip; - unsigned long pages; struct mutex lock; int irq1; int irq2; @@ -680,14 +679,15 @@ static void rcar_pcie_unmap_msi(struct rcar_pcie_host *host) static void rcar_pcie_hw_enable_msi(struct rcar_pcie_host *host) { struct rcar_pcie *pcie = &host->pcie; - struct rcar_msi *msi = &host->msi; - unsigned long base; + struct device *dev = pcie->dev; + struct resource res; + + if (WARN_ON(of_address_to_resource(dev->of_node, 0, &res))) + return; /* setup MSI data target */ - base = virt_to_phys((void *)msi->pages); - - rcar_pci_write_reg(pcie, lower_32_bits(base) | MSIFE, PCIEMSIALR); - rcar_pci_write_reg(pcie, upper_32_bits(base), PCIEMSIAUR); + rcar_pci_write_reg(pcie, lower_32_bits(res.start) | MSIFE, PCIEMSIALR); + rcar_pci_write_reg(pcie, upper_32_bits(res.start), PCIEMSIAUR); /* enable all MSI interrupts */ rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER); @@ -735,7 +735,6 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) } /* setup MSI data target */ - msi->pages = __get_free_pages(GFP_KERNEL | GFP_DMA32, 0); rcar_pcie_hw_enable_msi(host); return 0; @@ -748,7 +747,6 @@ err: static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host) { struct rcar_pcie *pcie = &host->pcie; - struct rcar_msi *msi = &host->msi; /* Disable all MSI interrupts */ rcar_pci_write_reg(pcie, 0, PCIEMSIIER); @@ -756,8 +754,6 @@ static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host) /* Disable address decoding of the MSI interrupt, MSIFE */ rcar_pci_write_reg(pcie, 0, PCIEMSIALR); - free_pages(msi->pages, 0); - rcar_pcie_unmap_msi(host); } From 83ed8d4fa656d37d17bb83203485e3f7a2360e7a Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:34 +0100 Subject: [PATCH 03/14] PCI: rcar: Convert to MSI domains In anticipation of the removal of the msi_controller structure, convert the Rcar host controller driver to MSI domains. We end-up with the usual two domain structure, the top one being a generic PCI/MSI domain, the bottom one being Rcar-specific and handling the actual HW interrupt allocation. Link: https://lore.kernel.org/r/20210330151145.997953-4-maz@kernel.org Tested-by: Marek Vasut Signed-off-by: Marc Zyngier [lorenzo.pieralisi@arm.com: merged fix https://lore.kernel.org/linux-pci/87y2e2p9wk.wl-maz@kernel.org] Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/controller/Kconfig | 1 - drivers/pci/controller/pcie-rcar-host.c | 369 ++++++++++++------------ 2 files changed, 178 insertions(+), 192 deletions(-) diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig index be8f9ff512a0..5cc07d28a3a0 100644 --- a/drivers/pci/controller/Kconfig +++ b/drivers/pci/controller/Kconfig @@ -58,7 +58,6 @@ config PCIE_RCAR_HOST bool "Renesas R-Car PCIe host controller" depends on ARCH_RENESAS || COMPILE_TEST depends on PCI_MSI_IRQ_DOMAIN - select PCI_MSI_ARCH_FALLBACKS help Say Y here if you want PCIe controller support on R-Car SoCs in host mode. diff --git a/drivers/pci/controller/pcie-rcar-host.c b/drivers/pci/controller/pcie-rcar-host.c index ce952403e22c..765cf2b45e24 100644 --- a/drivers/pci/controller/pcie-rcar-host.c +++ b/drivers/pci/controller/pcie-rcar-host.c @@ -35,17 +35,12 @@ struct rcar_msi { DECLARE_BITMAP(used, INT_PCI_MSI_NR); struct irq_domain *domain; - struct msi_controller chip; - struct mutex lock; + struct mutex map_lock; + spinlock_t mask_lock; int irq1; int irq2; }; -static inline struct rcar_msi *to_rcar_msi(struct msi_controller *chip) -{ - return container_of(chip, struct rcar_msi, chip); -} - /* Structure representing the PCIe interface */ struct rcar_pcie_host { struct rcar_pcie pcie; @@ -55,6 +50,11 @@ struct rcar_pcie_host { int (*phy_init_fn)(struct rcar_pcie_host *host); }; +static struct rcar_pcie_host *msi_to_host(struct rcar_msi *msi) +{ + return container_of(msi, struct rcar_pcie_host, msi); +} + static u32 rcar_read_conf(struct rcar_pcie *pcie, int where) { unsigned int shift = BITS_PER_BYTE * (where & 3); @@ -291,8 +291,6 @@ static int rcar_pcie_enable(struct rcar_pcie_host *host) bridge->sysdata = host; bridge->ops = &rcar_pcie_ops; - if (IS_ENABLED(CONFIG_PCI_MSI)) - bridge->msi = &host->msi.chip; return pci_host_probe(bridge); } @@ -472,42 +470,6 @@ static int rcar_pcie_phy_init_gen3(struct rcar_pcie_host *host) return err; } -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 int rcar_msi_alloc_region(struct rcar_msi *chip, int no_irqs) -{ - int msi; - - mutex_lock(&chip->lock); - msi = bitmap_find_free_region(chip->used, INT_PCI_MSI_NR, - order_base_2(no_irqs)); - 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_host *host = data; @@ -526,18 +488,13 @@ static irqreturn_t rcar_pcie_msi_irq(int irq, void *data) unsigned int index = find_first_bit(®, 32); unsigned int msi_irq; - /* clear the interrupt */ - rcar_pci_write_reg(pcie, 1 << index, PCIEMSIFR); - - msi_irq = irq_find_mapping(msi->domain, index); + msi_irq = irq_find_mapping(msi->domain->parent, index); if (msi_irq) { - if (test_bit(index, msi->used)) - generic_handle_irq(msi_irq); - else - dev_info(dev, "unhandled MSI\n"); + generic_handle_irq(msi_irq); } else { /* Unknown MSI, just clear it */ dev_dbg(dev, "unexpected MSI\n"); + rcar_pci_write_reg(pcie, BIT(index), PCIEMSIFR); } /* see if there's any more pending in this vector */ @@ -547,150 +504,169 @@ static irqreturn_t rcar_pcie_msi_irq(int irq, void *data) return IRQ_HANDLED; } -static int rcar_msi_setup_irq(struct msi_controller *chip, struct pci_dev *pdev, - struct msi_desc *desc) +static void rcar_msi_top_irq_ack(struct irq_data *d) { - struct rcar_msi *msi = to_rcar_msi(chip); - struct rcar_pcie_host *host = container_of(chip, struct rcar_pcie_host, - msi.chip); - struct rcar_pcie *pcie = &host->pcie; - struct msi_msg msg; - unsigned int irq; - int hwirq; - - hwirq = rcar_msi_alloc(msi); - if (hwirq < 0) - return hwirq; - - irq = irq_find_mapping(msi->domain, hwirq); - if (!irq) { - rcar_msi_free(msi, hwirq); - return -EINVAL; - } - - irq_set_msi_desc(irq, desc); - - msg.address_lo = rcar_pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE; - msg.address_hi = rcar_pci_read_reg(pcie, PCIEMSIAUR); - msg.data = hwirq; - - pci_write_msi_msg(irq, &msg); - - return 0; + irq_chip_ack_parent(d); } -static int rcar_msi_setup_irqs(struct msi_controller *chip, - struct pci_dev *pdev, int nvec, int type) +static void rcar_msi_top_irq_mask(struct irq_data *d) { - struct rcar_msi *msi = to_rcar_msi(chip); - struct rcar_pcie_host *host = container_of(chip, struct rcar_pcie_host, - msi.chip); - struct rcar_pcie *pcie = &host->pcie; - struct msi_desc *desc; - struct msi_msg msg; - unsigned int irq; + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void rcar_msi_top_irq_unmask(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip rcar_msi_top_chip = { + .name = "PCIe MSI", + .irq_ack = rcar_msi_top_irq_ack, + .irq_mask = rcar_msi_top_irq_mask, + .irq_unmask = rcar_msi_top_irq_unmask, +}; + +static void rcar_msi_irq_ack(struct irq_data *d) +{ + struct rcar_msi *msi = irq_data_get_irq_chip_data(d); + struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; + + /* clear the interrupt */ + rcar_pci_write_reg(pcie, BIT(d->hwirq), PCIEMSIFR); +} + +static void rcar_msi_irq_mask(struct irq_data *d) +{ + struct rcar_msi *msi = irq_data_get_irq_chip_data(d); + struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; + unsigned long flags; + u32 value; + + spin_lock_irqsave(&msi->mask_lock, flags); + value = rcar_pci_read_reg(pcie, PCIEMSIIER); + value &= ~BIT(d->hwirq); + rcar_pci_write_reg(pcie, value, PCIEMSIIER); + spin_unlock_irqrestore(&msi->mask_lock, flags); +} + +static void rcar_msi_irq_unmask(struct irq_data *d) +{ + struct rcar_msi *msi = irq_data_get_irq_chip_data(d); + struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; + unsigned long flags; + u32 value; + + spin_lock_irqsave(&msi->mask_lock, flags); + value = rcar_pci_read_reg(pcie, PCIEMSIIER); + value |= BIT(d->hwirq); + rcar_pci_write_reg(pcie, value, PCIEMSIIER); + spin_unlock_irqrestore(&msi->mask_lock, flags); +} + +static int rcar_msi_set_affinity(struct irq_data *d, const struct cpumask *mask, bool force) +{ + return -EINVAL; +} + +static void rcar_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct rcar_msi *msi = irq_data_get_irq_chip_data(data); + struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; + + msg->address_lo = rcar_pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE; + msg->address_hi = rcar_pci_read_reg(pcie, PCIEMSIAUR); + msg->data = data->hwirq; +} + +static struct irq_chip rcar_msi_bottom_chip = { + .name = "Rcar MSI", + .irq_ack = rcar_msi_irq_ack, + .irq_mask = rcar_msi_irq_mask, + .irq_unmask = rcar_msi_irq_unmask, + .irq_set_affinity = rcar_msi_set_affinity, + .irq_compose_msi_msg = rcar_compose_msi_msg, +}; + +static int rcar_msi_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct rcar_msi *msi = domain->host_data; + unsigned int i; int hwirq; - int i; - /* MSI-X interrupts are not supported */ - if (type == PCI_CAP_ID_MSIX) - return -EINVAL; + mutex_lock(&msi->map_lock); - WARN_ON(!list_is_singular(&pdev->dev.msi_list)); - desc = list_entry(pdev->dev.msi_list.next, struct msi_desc, list); + hwirq = bitmap_find_free_region(msi->used, INT_PCI_MSI_NR, order_base_2(nr_irqs)); + + mutex_unlock(&msi->map_lock); - hwirq = rcar_msi_alloc_region(msi, nvec); if (hwirq < 0) return -ENOSPC; - irq = irq_find_mapping(msi->domain, hwirq); - if (!irq) - return -ENOSPC; - - for (i = 0; i < nvec; i++) { - /* - * irq_create_mapping() called from rcar_pcie_probe() pre- - * allocates descs, so there is no need to allocate descs here. - * We can therefore assume that if irq_find_mapping() above - * returns non-zero, then the descs are also successfully - * allocated. - */ - if (irq_set_msi_desc_off(irq, i, desc)) { - /* TODO: clear */ - return -EINVAL; - } - } - - desc->nvec_used = nvec; - desc->msi_attrib.multiple = order_base_2(nvec); - - msg.address_lo = rcar_pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE; - msg.address_hi = rcar_pci_read_reg(pcie, PCIEMSIAUR); - msg.data = hwirq; - - pci_write_msi_msg(irq, &msg); + for (i = 0; i < nr_irqs; i++) + irq_domain_set_info(domain, virq + i, hwirq + i, + &rcar_msi_bottom_chip, domain->host_data, + handle_edge_irq, NULL, NULL); return 0; } -static void rcar_msi_teardown_irq(struct msi_controller *chip, unsigned int irq) +static void rcar_msi_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) { - struct rcar_msi *msi = to_rcar_msi(chip); - struct irq_data *d = irq_get_irq_data(irq); + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + struct rcar_msi *msi = domain->host_data; - rcar_msi_free(msi, d->hwirq); + mutex_lock(&msi->map_lock); + + bitmap_release_region(msi->used, d->hwirq, order_base_2(nr_irqs)); + + mutex_unlock(&msi->map_lock); } -static struct irq_chip rcar_msi_irq_chip = { - .name = "R-Car PCIe MSI", - .irq_enable = pci_msi_unmask_irq, - .irq_disable = pci_msi_mask_irq, - .irq_mask = pci_msi_mask_irq, - .irq_unmask = pci_msi_unmask_irq, +static const struct irq_domain_ops rcar_msi_domain_ops = { + .alloc = rcar_msi_domain_alloc, + .free = rcar_msi_domain_free, }; -static int rcar_msi_map(struct irq_domain *domain, unsigned int irq, - irq_hw_number_t hwirq) +static struct msi_domain_info rcar_msi_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_MULTI_PCI_MSI), + .chip = &rcar_msi_top_chip, +}; + +static int rcar_allocate_domains(struct rcar_msi *msi) { - irq_set_chip_and_handler(irq, &rcar_msi_irq_chip, handle_simple_irq); - irq_set_chip_data(irq, domain->host_data); + struct rcar_pcie *pcie = &msi_to_host(msi)->pcie; + struct fwnode_handle *fwnode = dev_fwnode(pcie->dev); + struct irq_domain *parent; + + parent = irq_domain_create_linear(fwnode, INT_PCI_MSI_NR, + &rcar_msi_domain_ops, msi); + if (!parent) { + dev_err(pcie->dev, "failed to create IRQ domain\n"); + return -ENOMEM; + } + irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS); + + msi->domain = pci_msi_create_irq_domain(fwnode, &rcar_msi_info, parent); + if (!msi->domain) { + dev_err(pcie->dev, "failed to create MSI domain\n"); + irq_domain_remove(parent); + return -ENOMEM; + } return 0; } -static const struct irq_domain_ops msi_domain_ops = { - .map = rcar_msi_map, -}; - -static void rcar_pcie_unmap_msi(struct rcar_pcie_host *host) +static void rcar_free_domains(struct rcar_msi *msi) { - struct rcar_msi *msi = &host->msi; - int i, irq; - - for (i = 0; i < INT_PCI_MSI_NR; i++) { - irq = irq_find_mapping(msi->domain, i); - if (irq > 0) - irq_dispose_mapping(irq); - } + struct irq_domain *parent = msi->domain->parent; irq_domain_remove(msi->domain); -} - -static void rcar_pcie_hw_enable_msi(struct rcar_pcie_host *host) -{ - struct rcar_pcie *pcie = &host->pcie; - struct device *dev = pcie->dev; - struct resource res; - - if (WARN_ON(of_address_to_resource(dev->of_node, 0, &res))) - return; - - /* setup MSI data target */ - rcar_pci_write_reg(pcie, lower_32_bits(res.start) | MSIFE, PCIEMSIALR); - rcar_pci_write_reg(pcie, upper_32_bits(res.start), PCIEMSIAUR); - - /* enable all MSI interrupts */ - rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER); + irq_domain_remove(parent); } static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) @@ -698,29 +674,24 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) struct rcar_pcie *pcie = &host->pcie; struct device *dev = pcie->dev; struct rcar_msi *msi = &host->msi; - int err, i; + struct resource res; + int err; - mutex_init(&msi->lock); + mutex_init(&msi->map_lock); + spin_lock_init(&msi->mask_lock); - msi->chip.dev = dev; - msi->chip.setup_irq = rcar_msi_setup_irq; - msi->chip.setup_irqs = rcar_msi_setup_irqs; - msi->chip.teardown_irq = rcar_msi_teardown_irq; + err = of_address_to_resource(dev->of_node, 0, &res); + if (err) + return err; - msi->domain = irq_domain_add_linear(dev->of_node, INT_PCI_MSI_NR, - &msi_domain_ops, &msi->chip); - if (!msi->domain) { - dev_err(dev, "failed to create IRQ domain\n"); - return -ENOMEM; - } - - for (i = 0; i < INT_PCI_MSI_NR; i++) - irq_create_mapping(msi->domain, i); + err = rcar_allocate_domains(msi); + if (err) + return err; /* Two irqs are for MSI, but they are also used for non-MSI irqs */ err = devm_request_irq(dev, msi->irq1, rcar_pcie_msi_irq, IRQF_SHARED | IRQF_NO_THREAD, - rcar_msi_irq_chip.name, host); + rcar_msi_bottom_chip.name, host); if (err < 0) { dev_err(dev, "failed to request IRQ: %d\n", err); goto err; @@ -728,19 +699,26 @@ static int rcar_pcie_enable_msi(struct rcar_pcie_host *host) err = devm_request_irq(dev, msi->irq2, rcar_pcie_msi_irq, IRQF_SHARED | IRQF_NO_THREAD, - rcar_msi_irq_chip.name, host); + rcar_msi_bottom_chip.name, host); if (err < 0) { dev_err(dev, "failed to request IRQ: %d\n", err); goto err; } - /* setup MSI data target */ - rcar_pcie_hw_enable_msi(host); + /* disable all MSIs */ + rcar_pci_write_reg(pcie, 0, PCIEMSIIER); + + /* + * Setup MSI data target using RC base address address, which + * is guaranteed to be in the low 32bit range on any RCar HW. + */ + rcar_pci_write_reg(pcie, lower_32_bits(res.start) | MSIFE, PCIEMSIALR); + rcar_pci_write_reg(pcie, upper_32_bits(res.start), PCIEMSIAUR); return 0; err: - rcar_pcie_unmap_msi(host); + rcar_free_domains(msi); return err; } @@ -754,7 +732,7 @@ static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host) /* Disable address decoding of the MSI interrupt, MSIFE */ rcar_pci_write_reg(pcie, 0, PCIEMSIALR); - rcar_pcie_unmap_msi(host); + rcar_free_domains(&host->msi); } static int rcar_pcie_get_resources(struct rcar_pcie_host *host) @@ -1007,8 +985,17 @@ static int __maybe_unused rcar_pcie_resume(struct device *dev) dev_info(dev, "PCIe x%d: link up\n", (data >> 20) & 0x3f); /* Enable MSI */ - if (IS_ENABLED(CONFIG_PCI_MSI)) - rcar_pcie_hw_enable_msi(host); + if (IS_ENABLED(CONFIG_PCI_MSI)) { + struct resource res; + u32 val; + + of_address_to_resource(dev->of_node, 0, &res); + rcar_pci_write_reg(pcie, upper_32_bits(res.start), PCIEMSIAUR); + rcar_pci_write_reg(pcie, lower_32_bits(res.start) | MSIFE, PCIEMSIALR); + + bitmap_to_arr32(&val, host->msi.used, INT_PCI_MSI_NR); + rcar_pci_write_reg(pcie, val, PCIEMSIIER); + } rcar_pcie_hw_enable(host); From 161260e7f7bc58d6a0972eb41a6072e82d0b58a5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:35 +0100 Subject: [PATCH 04/14] PCI: xilinx: Don't allocate extra memory for the MSI capture address A long cargo-culted behaviour of PCI drivers is to allocate memory to obtain an address that is fed to the controller as the MSI capture address (i.e. the MSI doorbell). But there is no actual requirement for this address to be RAM. All it needs to be is a suitable aligned address that will *not* be DMA'd to. Use the physical address of the 'port' data structure as the MSI capture address, aligned on a 4K boundary. Link: https://lore.kernel.org/r/20210330151145.997953-5-maz@kernel.org Tested-by: Bharat Kumar Gogada Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi --- drivers/pci/controller/pcie-xilinx.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/pci/controller/pcie-xilinx.c b/drivers/pci/controller/pcie-xilinx.c index fa5baeb82653..e127a7b6e535 100644 --- a/drivers/pci/controller/pcie-xilinx.c +++ b/drivers/pci/controller/pcie-xilinx.c @@ -94,7 +94,6 @@ * struct xilinx_pcie_port - PCIe port information * @reg_base: IO Mapped Register Base * @irq: Interrupt number - * @msi_pages: MSI pages * @dev: Device pointer * @msi_domain: MSI IRQ domain pointer * @leg_domain: Legacy IRQ domain pointer @@ -103,7 +102,6 @@ struct xilinx_pcie_port { void __iomem *reg_base; u32 irq; - unsigned long msi_pages; struct device *dev; struct irq_domain *msi_domain; struct irq_domain *leg_domain; @@ -274,10 +272,10 @@ static int xilinx_pcie_msi_setup_irq(struct msi_controller *chip, irq_set_msi_desc(irq, desc); - msg_addr = virt_to_phys((void *)port->msi_pages); + msg_addr = ALIGN_DOWN(virt_to_phys(port), SZ_4K); - msg.address_hi = 0; - msg.address_lo = msg_addr; + msg.address_hi = upper_32_bits(msg_addr); + msg.address_lo = lower_32_bits(msg_addr); msg.data = irq; pci_write_msi_msg(irq, &msg); @@ -330,13 +328,9 @@ static int xilinx_pcie_enable_msi(struct xilinx_pcie_port *port) { phys_addr_t msg_addr; - port->msi_pages = __get_free_pages(GFP_KERNEL, 0); - if (!port->msi_pages) - return -ENOMEM; - - msg_addr = virt_to_phys((void *)port->msi_pages); - pcie_write(port, 0x0, XILINX_PCIE_REG_MSIBASE1); - pcie_write(port, msg_addr, XILINX_PCIE_REG_MSIBASE2); + msg_addr = ALIGN_DOWN(virt_to_phys(port), SZ_4K); + pcie_write(port, upper_32_bits(msg_addr), XILINX_PCIE_REG_MSIBASE1); + pcie_write(port, lower_32_bits(msg_addr), XILINX_PCIE_REG_MSIBASE2); return 0; } From 313b64c3ae52bc8e953319077204cf1d286a8a99 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:36 +0100 Subject: [PATCH 05/14] PCI: xilinx: Convert to MSI domains In anticipation of the removal of the msi_controller structure, convert the ancient xilinx host controller driver to MSI domains. We end-up with the usual two domain structure, the top one being a generic PCI/MSI domain, the bottom one being xilinx-specific and handling the actual HW interrupt allocation. This allows us to fix some of the most appaling MSI programming, where the message programmed in the device is the virtual IRQ number instead of the allocated vector number. The allocator is also made safe with a mutex. This should allow support for MultiMSI, but I decided not to even try, since I cannot test it. Link: https://lore.kernel.org/r/20210330151145.997953-6-maz@kernel.org Tested-by: Bharat Kumar Gogada Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/controller/Kconfig | 2 +- drivers/pci/controller/pcie-xilinx.c | 270 ++++++++++++--------------- 2 files changed, 120 insertions(+), 152 deletions(-) diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig index 5cc07d28a3a0..60045f7aafc5 100644 --- a/drivers/pci/controller/Kconfig +++ b/drivers/pci/controller/Kconfig @@ -86,7 +86,7 @@ config PCI_HOST_GENERIC config PCIE_XILINX bool "Xilinx AXI PCIe host bridge support" depends on OF || COMPILE_TEST - select PCI_MSI_ARCH_FALLBACKS + depends on PCI_MSI_IRQ_DOMAIN help Say 'Y' here if you want kernel to support the Xilinx AXI PCIe Host Bridge driver. diff --git a/drivers/pci/controller/pcie-xilinx.c b/drivers/pci/controller/pcie-xilinx.c index e127a7b6e535..14001febf59a 100644 --- a/drivers/pci/controller/pcie-xilinx.c +++ b/drivers/pci/controller/pcie-xilinx.c @@ -93,23 +93,23 @@ /** * struct xilinx_pcie_port - PCIe port information * @reg_base: IO Mapped Register Base - * @irq: Interrupt number * @dev: Device pointer + * @msi_map: Bitmap of allocated MSIs + * @map_lock: Mutex protecting the MSI allocation * @msi_domain: MSI IRQ domain pointer * @leg_domain: Legacy IRQ domain pointer * @resources: Bus Resources */ struct xilinx_pcie_port { void __iomem *reg_base; - u32 irq; struct device *dev; + unsigned long msi_map[BITS_TO_LONGS(XILINX_NUM_MSI_IRQS)]; + struct mutex map_lock; struct irq_domain *msi_domain; struct irq_domain *leg_domain; struct list_head resources; }; -static DECLARE_BITMAP(msi_irq_in_use, XILINX_NUM_MSI_IRQS); - static inline u32 pcie_read(struct xilinx_pcie_port *port, u32 reg) { return readl(port->reg_base + reg); @@ -194,145 +194,116 @@ static struct pci_ops xilinx_pcie_ops = { /* MSI functions */ -/** - * xilinx_pcie_destroy_msi - Free MSI number - * @irq: IRQ to be freed - */ -static void xilinx_pcie_destroy_msi(unsigned int irq) +static void xilinx_msi_top_irq_ack(struct irq_data *d) { - struct msi_desc *msi; - struct xilinx_pcie_port *port; - struct irq_data *d = irq_get_irq_data(irq); - irq_hw_number_t hwirq = irqd_to_hwirq(d); - - if (!test_bit(hwirq, msi_irq_in_use)) { - msi = irq_get_msi_desc(irq); - port = msi_desc_to_pci_sysdata(msi); - dev_err(port->dev, "Trying to free unused MSI#%d\n", irq); - } else { - clear_bit(hwirq, msi_irq_in_use); - } + /* + * xilinx_pcie_intr_handler() will have performed the Ack. + * Eventually, this should be fixed and the Ack be moved in + * the respective callbacks for INTx and MSI. + */ } -/** - * xilinx_pcie_assign_msi - Allocate MSI number - * - * Return: A valid IRQ on success and error value on failure. - */ -static int xilinx_pcie_assign_msi(void) -{ - int pos; +static struct irq_chip xilinx_msi_top_chip = { + .name = "PCIe MSI", + .irq_ack = xilinx_msi_top_irq_ack, +}; - pos = find_first_zero_bit(msi_irq_in_use, XILINX_NUM_MSI_IRQS); - if (pos < XILINX_NUM_MSI_IRQS) - set_bit(pos, msi_irq_in_use); - else +static int xilinx_msi_set_affinity(struct irq_data *d, const struct cpumask *mask, bool force) +{ + return -EINVAL; +} + +static void xilinx_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct xilinx_pcie_port *pcie = irq_data_get_irq_chip_data(data); + phys_addr_t pa = ALIGN_DOWN(virt_to_phys(pcie), SZ_4K); + + msg->address_lo = lower_32_bits(pa); + msg->address_hi = upper_32_bits(pa); + msg->data = data->hwirq; +} + +static struct irq_chip xilinx_msi_bottom_chip = { + .name = "Xilinx MSI", + .irq_set_affinity = xilinx_msi_set_affinity, + .irq_compose_msi_msg = xilinx_compose_msi_msg, +}; + +static int xilinx_msi_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct xilinx_pcie_port *port = domain->host_data; + int hwirq, i; + + mutex_lock(&port->map_lock); + + hwirq = bitmap_find_free_region(port->msi_map, XILINX_NUM_MSI_IRQS, order_base_2(nr_irqs)); + + mutex_unlock(&port->map_lock); + + if (hwirq < 0) return -ENOSPC; - return pos; -} - -/** - * xilinx_msi_teardown_irq - Destroy the MSI - * @chip: MSI Chip descriptor - * @irq: MSI IRQ to destroy - */ -static void xilinx_msi_teardown_irq(struct msi_controller *chip, - unsigned int irq) -{ - xilinx_pcie_destroy_msi(irq); - irq_dispose_mapping(irq); -} - -/** - * xilinx_pcie_msi_setup_irq - Setup MSI request - * @chip: MSI chip pointer - * @pdev: PCIe device pointer - * @desc: MSI descriptor pointer - * - * Return: '0' on success and error value on failure - */ -static int xilinx_pcie_msi_setup_irq(struct msi_controller *chip, - struct pci_dev *pdev, - struct msi_desc *desc) -{ - struct xilinx_pcie_port *port = pdev->bus->sysdata; - unsigned int irq; - int hwirq; - struct msi_msg msg; - phys_addr_t msg_addr; - - hwirq = xilinx_pcie_assign_msi(); - if (hwirq < 0) - return hwirq; - - irq = irq_create_mapping(port->msi_domain, hwirq); - if (!irq) - return -EINVAL; - - irq_set_msi_desc(irq, desc); - - msg_addr = ALIGN_DOWN(virt_to_phys(port), SZ_4K); - - msg.address_hi = upper_32_bits(msg_addr); - msg.address_lo = lower_32_bits(msg_addr); - msg.data = irq; - - pci_write_msi_msg(irq, &msg); + for (i = 0; i < nr_irqs; i++) + irq_domain_set_info(domain, virq + i, hwirq + i, + &xilinx_msi_bottom_chip, domain->host_data, + handle_edge_irq, NULL, NULL); return 0; } -/* MSI Chip Descriptor */ -static struct msi_controller xilinx_pcie_msi_chip = { - .setup_irq = xilinx_pcie_msi_setup_irq, - .teardown_irq = xilinx_msi_teardown_irq, -}; - -/* HW Interrupt Chip Descriptor */ -static struct irq_chip xilinx_msi_irq_chip = { - .name = "Xilinx PCIe MSI", - .irq_enable = pci_msi_unmask_irq, - .irq_disable = pci_msi_mask_irq, - .irq_mask = pci_msi_mask_irq, - .irq_unmask = pci_msi_unmask_irq, -}; - -/** - * xilinx_pcie_msi_map - Set the handler for the MSI and mark IRQ as valid - * @domain: IRQ domain - * @irq: Virtual IRQ number - * @hwirq: HW interrupt number - * - * Return: Always returns 0. - */ -static int xilinx_pcie_msi_map(struct irq_domain *domain, unsigned int irq, - irq_hw_number_t hwirq) +static void xilinx_msi_domain_free(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs) { - irq_set_chip_and_handler(irq, &xilinx_msi_irq_chip, handle_simple_irq); - irq_set_chip_data(irq, domain->host_data); + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + struct xilinx_pcie_port *port = domain->host_data; + + mutex_lock(&port->map_lock); + + bitmap_release_region(port->msi_map, d->hwirq, order_base_2(nr_irqs)); + + mutex_unlock(&port->map_lock); +} + +static const struct irq_domain_ops xilinx_msi_domain_ops = { + .alloc = xilinx_msi_domain_alloc, + .free = xilinx_msi_domain_free, +}; + +static struct msi_domain_info xilinx_msi_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .chip = &xilinx_msi_top_chip, +}; + +static int xilinx_allocate_msi_domains(struct xilinx_pcie_port *pcie) +{ + struct fwnode_handle *fwnode = dev_fwnode(pcie->dev); + struct irq_domain *parent; + + parent = irq_domain_create_linear(fwnode, XILINX_NUM_MSI_IRQS, + &xilinx_msi_domain_ops, pcie); + if (!parent) { + dev_err(pcie->dev, "failed to create IRQ domain\n"); + return -ENOMEM; + } + irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS); + + pcie->msi_domain = pci_msi_create_irq_domain(fwnode, &xilinx_msi_info, parent); + if (!pcie->msi_domain) { + dev_err(pcie->dev, "failed to create MSI domain\n"); + irq_domain_remove(parent); + return -ENOMEM; + } return 0; } -/* IRQ Domain operations */ -static const struct irq_domain_ops msi_domain_ops = { - .map = xilinx_pcie_msi_map, -}; - -/** - * xilinx_pcie_enable_msi - Enable MSI support - * @port: PCIe port information - */ -static int xilinx_pcie_enable_msi(struct xilinx_pcie_port *port) +static void xilinx_free_msi_domains(struct xilinx_pcie_port *pcie) { - phys_addr_t msg_addr; + struct irq_domain *parent = pcie->msi_domain->parent; - msg_addr = ALIGN_DOWN(virt_to_phys(port), SZ_4K); - pcie_write(port, upper_32_bits(msg_addr), XILINX_PCIE_REG_MSIBASE1); - pcie_write(port, lower_32_bits(msg_addr), XILINX_PCIE_REG_MSIBASE2); - - return 0; + irq_domain_remove(pcie->msi_domain); + irq_domain_remove(parent); } /* INTx Functions */ @@ -414,6 +385,8 @@ static irqreturn_t xilinx_pcie_intr_handler(int irq, void *data) } if (status & (XILINX_PCIE_INTR_INTX | XILINX_PCIE_INTR_MSI)) { + unsigned int irq; + val = pcie_read(port, XILINX_PCIE_REG_RPIFR1); /* Check whether interrupt valid */ @@ -426,20 +399,19 @@ static irqreturn_t xilinx_pcie_intr_handler(int irq, void *data) if (val & XILINX_PCIE_RPIFR1_MSI_INTR) { val = pcie_read(port, XILINX_PCIE_REG_RPIFR2) & XILINX_PCIE_RPIFR2_MSG_DATA; + irq = irq_find_mapping(port->msi_domain->parent, val); } else { val = (val & XILINX_PCIE_RPIFR1_INTR_MASK) >> XILINX_PCIE_RPIFR1_INTR_SHIFT; - val = irq_find_mapping(port->leg_domain, val); + irq = irq_find_mapping(port->leg_domain, val); } /* Clear interrupt FIFO register 1 */ pcie_write(port, XILINX_PCIE_RPIFR1_ALL_MASK, XILINX_PCIE_REG_RPIFR1); - /* Handle the interrupt */ - if (IS_ENABLED(CONFIG_PCI_MSI) || - !(val & XILINX_PCIE_RPIFR1_MSI_INTR)) - generic_handle_irq(val); + if (irq) + generic_handle_irq(irq); } if (status & XILINX_PCIE_INTR_SLV_UNSUPP) @@ -485,12 +457,11 @@ error: static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port) { struct device *dev = port->dev; - struct device_node *node = dev->of_node; struct device_node *pcie_intc_node; int ret; /* Setup INTx */ - pcie_intc_node = of_get_next_child(node, NULL); + pcie_intc_node = of_get_next_child(dev->of_node, NULL); if (!pcie_intc_node) { dev_err(dev, "No PCIe Intc node found\n"); return -ENODEV; @@ -507,18 +478,14 @@ static int xilinx_pcie_init_irq_domain(struct xilinx_pcie_port *port) /* Setup MSI */ if (IS_ENABLED(CONFIG_PCI_MSI)) { - port->msi_domain = irq_domain_add_linear(node, - XILINX_NUM_MSI_IRQS, - &msi_domain_ops, - &xilinx_pcie_msi_chip); - if (!port->msi_domain) { - dev_err(dev, "Failed to get a MSI IRQ domain\n"); - return -ENODEV; - } + phys_addr_t pa = ALIGN_DOWN(virt_to_phys(port), SZ_4K); - ret = xilinx_pcie_enable_msi(port); + ret = xilinx_allocate_msi_domains(port); if (ret) return ret; + + pcie_write(port, upper_32_bits(pa), XILINX_PCIE_REG_MSIBASE1); + pcie_write(port, lower_32_bits(pa), XILINX_PCIE_REG_MSIBASE2); } return 0; @@ -566,6 +533,7 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port) struct device *dev = port->dev; struct device_node *node = dev->of_node; struct resource regs; + unsigned int irq; int err; err = of_address_to_resource(node, 0, ®s); @@ -578,12 +546,12 @@ static int xilinx_pcie_parse_dt(struct xilinx_pcie_port *port) if (IS_ERR(port->reg_base)) return PTR_ERR(port->reg_base); - port->irq = irq_of_parse_and_map(node, 0); - err = devm_request_irq(dev, port->irq, xilinx_pcie_intr_handler, + irq = irq_of_parse_and_map(node, 0); + err = devm_request_irq(dev, irq, xilinx_pcie_intr_handler, IRQF_SHARED | IRQF_NO_THREAD, "xilinx-pcie", port); if (err) { - dev_err(dev, "unable to request irq %d\n", port->irq); + dev_err(dev, "unable to request irq %d\n", irq); return err; } @@ -611,7 +579,7 @@ static int xilinx_pcie_probe(struct platform_device *pdev) return -ENODEV; port = pci_host_bridge_priv(bridge); - + mutex_init(&port->map_lock); port->dev = dev; err = xilinx_pcie_parse_dt(port); @@ -631,11 +599,11 @@ static int xilinx_pcie_probe(struct platform_device *pdev) bridge->sysdata = port; bridge->ops = &xilinx_pcie_ops; -#ifdef CONFIG_PCI_MSI - xilinx_pcie_msi_chip.dev = dev; - bridge->msi = &xilinx_pcie_msi_chip; -#endif - return pci_host_probe(bridge); + err = pci_host_probe(bridge); + if (err) + xilinx_free_msi_domains(port); + + return err; } static const struct of_device_id xilinx_pcie_of_match[] = { From e0fad163b6e7482be32ae99662240268aa0e1bf1 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:37 +0100 Subject: [PATCH 06/14] PCI: hv: Drop msi_controller structure The Hyper-V PCI driver still makes use of a msi_controller structure, but it looks more like a distant leftover than anything actually useful, since it is initialised to 0 and never used for anything. Just remove it. Link: https://lore.kernel.org/r/20210330151145.997953-7-maz@kernel.org Tested-by: Michael Kelley Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Reviewed-by: Michael Kelley Acked-by: Bjorn Helgaas --- drivers/pci/controller/pci-hyperv.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c index 27a17a1e4a7c..2c014ba7ed4b 100644 --- a/drivers/pci/controller/pci-hyperv.c +++ b/drivers/pci/controller/pci-hyperv.c @@ -473,7 +473,6 @@ struct hv_pcibus_device { struct list_head dr_list; struct msi_domain_info msi_info; - struct msi_controller msi_chip; struct irq_domain *irq_domain; spinlock_t retarget_msi_interrupt_lock; @@ -1866,9 +1865,6 @@ static int create_root_hv_pci_bus(struct hv_pcibus_device *hbus) if (!hbus->pci_bus) return -ENODEV; - hbus->pci_bus->msi = &hbus->msi_chip; - hbus->pci_bus->msi->dev = &hbus->hdev->device; - pci_lock_rescan_remove(); pci_scan_child_bus(hbus->pci_bus); hv_pci_assign_numa_node(hbus); From 3a05d08f6cc75b74079290c33d6127b2857226fa Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:38 +0100 Subject: [PATCH 07/14] PCI/MSI: Drop use of msi_controller from core code As there is no driver using msi_controller, we can now safely remove its use from the PCI probe code. Link: https://lore.kernel.org/r/20210330151145.997953-8-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/msi.c | 23 +---------------------- drivers/pci/probe.c | 2 -- include/linux/pci.h | 2 -- 3 files changed, 1 insertion(+), 26 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 3162f88fe940..79b5a995bd02 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -64,39 +64,18 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) /* Arch hooks */ int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc) { - struct msi_controller *chip = dev->bus->msi; - int err; - - if (!chip || !chip->setup_irq) - return -EINVAL; - - err = chip->setup_irq(chip, dev, desc); - if (err < 0) - return err; - - irq_set_chip_data(desc->irq, chip); - - return 0; + return -EINVAL; } void __weak arch_teardown_msi_irq(unsigned int irq) { - struct msi_controller *chip = irq_get_chip_data(irq); - - if (!chip || !chip->teardown_irq) - return; - - chip->teardown_irq(chip, irq); } int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) { - struct msi_controller *chip = dev->bus->msi; struct msi_desc *entry; int ret; - if (chip && chip->setup_irqs) - return chip->setup_irqs(chip, dev, nvec, type); /* * If an architecture wants to support multiple MSI, it needs to * override arch_setup_msi_irqs() diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 953f15abc850..fb04fc81a8bd 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -895,7 +895,6 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) /* Temporarily move resources off the list */ list_splice_init(&bridge->windows, &resources); bus->sysdata = bridge->sysdata; - bus->msi = bridge->msi; bus->ops = bridge->ops; bus->number = bus->busn_res.start = bridge->busnr; #ifdef CONFIG_PCI_DOMAINS_GENERIC @@ -1053,7 +1052,6 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, return NULL; child->parent = parent; - child->msi = parent->msi; child->sysdata = parent->sysdata; child->bus_flags = parent->bus_flags; diff --git a/include/linux/pci.h b/include/linux/pci.h index 86c799c97b77..ebf557e59d87 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -540,7 +540,6 @@ struct pci_host_bridge { int (*map_irq)(const struct pci_dev *, u8, u8); void (*release_fn)(struct pci_host_bridge *); void *release_data; - struct msi_controller *msi; unsigned int ignore_reset_delay:1; /* For entire hierarchy */ unsigned int no_ext_tags:1; /* No Extended Tags */ unsigned int native_aer:1; /* OS may use PCIe AER */ @@ -621,7 +620,6 @@ struct pci_bus { struct resource busn_res; /* Bus numbers routed to this bus */ struct pci_ops *ops; /* Configuration access functions */ - struct msi_controller *msi; /* MSI controller */ void *sysdata; /* Hook for sys-specific extension */ struct proc_dir_entry *procdir; /* Directory entry in /proc/bus/pci */ From b227be0d7314d0869d4e28c199ac1fc7075cf06e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:39 +0100 Subject: [PATCH 08/14] PCI/MSI: Kill msi_controller structure msi_controller had a good, long life as the abstraction for a driver providing MSIs to PCI devices. But it has been replaced in all drivers by the more expressive generic MSI framework. Farewell, struct msi_controller. Link: https://lore.kernel.org/r/20210330151145.997953-9-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- include/linux/msi.h | 16 +--------------- 1 file changed, 1 insertion(+), 15 deletions(-) diff --git a/include/linux/msi.h b/include/linux/msi.h index aef35fd1cf11..3f21e77b57b7 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -240,8 +240,7 @@ void pci_msi_unmask_irq(struct irq_data *data); /* * The arch hooks to setup up msi irqs. Default functions are implemented * as weak symbols so that they /can/ be overriden by architecture specific - * code if needed. These hooks must be enabled by the architecture or by - * drivers which depend on them via msi_controller based MSI handling. + * code if needed. These hooks can only be enabled by the architecture. * * If CONFIG_PCI_MSI_ARCH_FALLBACKS is not selected they are replaced by * stubs with warnings. @@ -272,19 +271,6 @@ static inline void arch_teardown_msi_irqs(struct pci_dev *dev) void arch_restore_msi_irqs(struct pci_dev *dev); void default_restore_msi_irqs(struct pci_dev *dev); -struct msi_controller { - struct module *owner; - struct device *dev; - struct device_node *of_node; - struct list_head list; - - int (*setup_irq)(struct msi_controller *chip, struct pci_dev *dev, - struct msi_desc *desc); - int (*setup_irqs)(struct msi_controller *chip, struct pci_dev *dev, - int nvec, int type); - void (*teardown_irq)(struct msi_controller *chip, unsigned int irq); -}; - #ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN #include From f8bcf249d9cf292c6ceb3d9f5bd90815090f5286 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:40 +0100 Subject: [PATCH 09/14] PCI/MSI: Kill default_teardown_msi_irqs() It doesn't have any caller left. Link: https://lore.kernel.org/r/20210330151145.997953-10-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/msi.c | 11 +---------- include/linux/msi.h | 1 - 2 files changed, 1 insertion(+), 11 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 79b5a995bd02..d9c73c173c14 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -94,11 +94,7 @@ int __weak arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) return 0; } -/* - * We have a default implementation available as a separate non-weak - * function, as it is used by the Xen x86 PCI code - */ -void default_teardown_msi_irqs(struct pci_dev *dev) +void __weak arch_teardown_msi_irqs(struct pci_dev *dev) { int i; struct msi_desc *entry; @@ -108,11 +104,6 @@ void default_teardown_msi_irqs(struct pci_dev *dev) for (i = 0; i < entry->nvec_used; i++) arch_teardown_msi_irq(entry->irq + i); } - -void __weak arch_teardown_msi_irqs(struct pci_dev *dev) -{ - return default_teardown_msi_irqs(dev); -} #endif /* CONFIG_PCI_MSI_ARCH_FALLBACKS */ static void default_restore_msi_irq(struct pci_dev *dev, int irq) diff --git a/include/linux/msi.h b/include/linux/msi.h index 3f21e77b57b7..6aff469e511d 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -250,7 +250,6 @@ int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc); void arch_teardown_msi_irq(unsigned int irq); int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type); void arch_teardown_msi_irqs(struct pci_dev *dev); -void default_teardown_msi_irqs(struct pci_dev *dev); #else static inline int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) { From 94e89b145371b68fa0ea294855adebcd03e0522e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:41 +0100 Subject: [PATCH 10/14] PCI/MSI: Let PCI host bridges declare their reliance on MSI domains There is a whole class of host bridges that cannot know whether MSIs will be provided or not, as they rely on other blocks to provide the MSI functionnality, using MSI domains. This is the case for example on systems that use the ARM GIC architecture. Introduce a new attribute ('msi_domain') indicating that implicit dependency, and use this property to set the NO_MSI flag when no MSI domain is found at probe time. Link: https://lore.kernel.org/r/20210330151145.997953-11-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/probe.c | 2 ++ include/linux/pci.h | 1 + 2 files changed, 3 insertions(+) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index fb04fc81a8bd..aa6fba35f5d1 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -925,6 +925,8 @@ static int pci_register_host_bridge(struct pci_host_bridge *bridge) device_enable_async_suspend(bus->bridge); pci_set_bus_of_node(bus); pci_set_bus_msi_domain(bus); + if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev)) + bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI; if (!parent) set_dev_node(bus->bridge, pcibus_to_node(bus)); diff --git a/include/linux/pci.h b/include/linux/pci.h index ebf557e59d87..ede0aef2cfd4 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -550,6 +550,7 @@ struct pci_host_bridge { unsigned int native_dpc:1; /* OS may use PCIe DPC */ unsigned int preserve_config:1; /* Preserve FW resource setup */ unsigned int size_windows:1; /* Enable root bus sizing */ + unsigned int msi_domain:1; /* Bridge wants MSI domain */ /* Resource alignment requirements */ resource_size_t (*align_resource)(struct pci_dev *dev, From 9ec37efb87832b578d7972fc80b04d94f5d2bbe3 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:42 +0100 Subject: [PATCH 11/14] PCI/MSI: Make pci_host_common_probe() declare its reliance on MSI domains The generic PCI host driver relies on MSI domains for MSIs to be provided to its end-points. Make this dependency explicit. This cures the warnings occuring on arm/arm64 VMs when booted with PCI virtio devices and no MSI controller (no GICv3 ITS, for example). It is likely that other drivers will need to express the same dependency. Link: https://lore.kernel.org/r/20210330151145.997953-12-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/controller/pci-host-common.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pci/controller/pci-host-common.c b/drivers/pci/controller/pci-host-common.c index 6ab694f8d283..d3924a44db02 100644 --- a/drivers/pci/controller/pci-host-common.c +++ b/drivers/pci/controller/pci-host-common.c @@ -79,6 +79,7 @@ int pci_host_common_probe(struct platform_device *pdev) bridge->sysdata = cfg; bridge->ops = (struct pci_ops *)&ops->pci_ops; + bridge->msi_domain = true; return pci_host_probe(bridge); } From 645e9c38383d7fcde2784ee537fa18ec9bed54d9 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 30 Mar 2021 16:11:43 +0100 Subject: [PATCH 12/14] PCI: mediatek: Advertise lack of built-in MSI handling Some Mediatek host bridges cannot handle MSIs, which is sad. This also results in an ugly warning at device probe time, as the core PCI code wasn't told that MSIs were not available. Advertise this fact to the rest of the core PCI code by using the 'msi_domain' attribute, which still opens the possibility for another block to provide the MSI functionnality. [maz: commit message, switched over to msi_domain attribute] Link: https://lore.kernel.org/r/20210330151145.997953-13-maz@kernel.org Reported-by: Frank Wunderlich Signed-off-by: Thomas Gleixner Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/controller/pcie-mediatek.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c index 23548b517e4b..9c10d87b6134 100644 --- a/drivers/pci/controller/pcie-mediatek.c +++ b/drivers/pci/controller/pcie-mediatek.c @@ -143,6 +143,7 @@ struct mtk_pcie_port; * struct mtk_pcie_soc - differentiate between host generations * @need_fix_class_id: whether this host's class ID needed to be fixed or not * @need_fix_device_id: whether this host's device ID needed to be fixed or not + * @no_msi: Bridge has no MSI support, and relies on an external block * @device_id: device ID which this host need to be fixed * @ops: pointer to configuration access functions * @startup: pointer to controller setting functions @@ -151,6 +152,7 @@ struct mtk_pcie_port; struct mtk_pcie_soc { bool need_fix_class_id; bool need_fix_device_id; + bool no_msi; unsigned int device_id; struct pci_ops *ops; int (*startup)(struct mtk_pcie_port *port); @@ -1087,6 +1089,7 @@ static int mtk_pcie_probe(struct platform_device *pdev) host->ops = pcie->soc->ops; host->sysdata = pcie; + host->msi_domain = pcie->soc->no_msi; err = pci_host_probe(host); if (err) @@ -1176,6 +1179,7 @@ static const struct dev_pm_ops mtk_pcie_pm_ops = { }; static const struct mtk_pcie_soc mtk_pcie_soc_v1 = { + .no_msi = true, .ops = &mtk_pcie_ops, .startup = mtk_pcie_startup_port, }; From 61af69296cbadf4c88a1076a3b3e5572827b04c8 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:44 +0100 Subject: [PATCH 13/14] PCI/MSI: Document the various ways of ending up with NO_MSI We have now three ways of ending up with NO_MSI being set. Document them. Link: https://lore.kernel.org/r/20210330151145.997953-14-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/msi.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index d9c73c173c14..217dc9f0231f 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -871,8 +871,15 @@ static int pci_msi_supported(struct pci_dev *dev, int nvec) * Any bridge which does NOT route MSI transactions from its * secondary bus to its primary bus must set NO_MSI flag on * the secondary pci_bus. - * We expect only arch-specific PCI host bus controller driver - * or quirks for specific PCI bridges to be setting NO_MSI. + * + * The NO_MSI flag can either be set directly by: + * - arch-specific PCI host bus controller drivers (deprecated) + * - quirks for specific PCI bridges + * + * or indirectly by platform-specific PCI host bridge drivers by + * advertising the 'msi_domain' property, which results in + * the NO_MSI flag when no MSI domain is found for this bridge + * at probe time. */ for (bus = dev->bus; bus; bus = bus->parent) if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI) From 557853f4e23e60b6c5a6ec4771bbdf39bbae15d0 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 30 Mar 2021 16:11:45 +0100 Subject: [PATCH 14/14] PCI: Refactor HT advertising of NO_MSI flag The few quirks that deal with NO_MSI tend to be copy-paste heavy. Refactor them so that the hierarchy of conditions is slightly cleaner. Link: https://lore.kernel.org/r/20210330151145.997953-15-maz@kernel.org Signed-off-by: Marc Zyngier Signed-off-by: Lorenzo Pieralisi Acked-by: Bjorn Helgaas --- drivers/pci/quirks.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 653660e3ba9e..972bb0f9f994 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2585,10 +2585,8 @@ static int msi_ht_cap_enabled(struct pci_dev *dev) /* Check the HyperTransport MSI mapping to know whether MSI is enabled or not */ static void quirk_msi_ht_cap(struct pci_dev *dev) { - if (dev->subordinate && !msi_ht_cap_enabled(dev)) { - pci_warn(dev, "MSI quirk detected; subordinate MSI disabled\n"); - dev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI; - } + if (!msi_ht_cap_enabled(dev)) + quirk_disable_msi(dev); } DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_HT2000_PCIE, quirk_msi_ht_cap); @@ -2601,9 +2599,6 @@ static void quirk_nvidia_ck804_msi_ht_cap(struct pci_dev *dev) { struct pci_dev *pdev; - if (!dev->subordinate) - return; - /* * Check HT MSI cap on this chipset and the root one. A single one * having MSI is enough to be sure that MSI is supported. @@ -2611,10 +2606,8 @@ static void quirk_nvidia_ck804_msi_ht_cap(struct pci_dev *dev) pdev = pci_get_slot(dev->bus, 0); if (!pdev) return; - if (!msi_ht_cap_enabled(dev) && !msi_ht_cap_enabled(pdev)) { - pci_warn(dev, "MSI quirk detected; subordinate MSI disabled\n"); - dev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI; - } + if (!msi_ht_cap_enabled(pdev)) + quirk_msi_ht_cap(dev); pci_dev_put(pdev); } DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_CK804_PCIE,