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author | 2021-03-30 16:11:32 +0100 | |
---|---|---|
committer | 2021-04-20 14:11:01 +0100 | |
commit | 2c99e55f795593c5f029f65c4b4ab2a72bb076a3 (patch) | |
tree | 8a577adf26bad7055af43bd8cf6c4f2830863f18 /drivers/pci | |
parent | Linux 5.12-rc2 (diff) | |
download | linux-2c99e55f795593c5f029f65c4b4ab2a72bb076a3.tar.gz linux-2c99e55f795593c5f029f65c4b4ab2a72bb076a3.tar.bz2 linux-2c99e55f795593c5f029f65c4b4ab2a72bb076a3.zip |
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 <treding@nvidia.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/controller/Kconfig | 1 | ||||
-rw-r--r-- | drivers/pci/controller/pci-tegra.c | 349 |
2 files changed, 191 insertions, 159 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 <linux/interrupt.h> #include <linux/iopoll.h> #include <linux/irq.h> +#include <linux/irqchip/chained_irq.h> #include <linux/irqdomain.h> #include <linux/kernel.h> #include <linux/init.h> @@ -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) -{ - 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) +static void tegra_pcie_msi_irq(struct irq_desc *desc) { - 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; + irq_chip_ack_parent(d); +} - hwirq = tegra_msi_alloc(msi); - if (hwirq < 0) - return hwirq; +static void tegra_msi_top_irq_mask(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} - irq = irq_create_mapping(msi->domain, hwirq); - if (!irq) { - tegra_msi_free(msi, hwirq); - return -EINVAL; - } +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, +}; - irq_set_msi_desc(irq, desc); +static void tegra_msi_irq_ack(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; - msg.address_lo = lower_32_bits(msi->phys); - msg.address_hi = upper_32_bits(msi->phys); - msg.data = hwirq; + /* clear the interrupt */ + afi_writel(pcie, BIT(d->hwirq % 32), AFI_MSI_VEC(index)); +} - pci_write_msi_msg(irq, &msg); +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; - return 0; + 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_teardown_irq(struct msi_controller *chip, - unsigned int irq) +static void tegra_msi_irq_unmask(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); + 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; - irq_dispose_mapping(irq); - tegra_msi_free(msi, hwirq); + 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 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 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_map(struct irq_domain *domain, unsigned int irq, - irq_hw_number_t hwirq) +static int tegra_msi_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) { - 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 = 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); - - msi->chip.dev = dev; - msi->chip.setup_irq = tegra_msi_setup_irq; - msi->chip.teardown_irq = tegra_msi_teardown_irq; + mutex_init(&msi->map_lock); + spin_lock_init(&msi->mask_lock); - 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; } |