The PLIC driver does not require very early initialization so let us convert it into a platform driver. As part of the conversion, the PLIC probing undergoes the following changes: 1. Use dev_info(), dev_err() and dev_warn() instead of pr_info(), pr_err() and pr_warn() 2. Use devm_xyz() APIs wherever applicable 3. PLIC is now probed after CPUs are brought-up so we have to setup cpuhp state after context handler of all online CPUs are initialized otherwise we see crash on multi-socket systems Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx> --- drivers/irqchip/irq-sifive-plic.c | 269 ++++++++++++++++++++---------- 1 file changed, 177 insertions(+), 92 deletions(-) diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 5b7bc4fd9517..48483a1a41dd 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -3,7 +3,6 @@ * Copyright (C) 2017 SiFive * Copyright (C) 2018 Christoph Hellwig */ -#define pr_fmt(fmt) "plic: " fmt #include <linux/cpu.h> #include <linux/interrupt.h> #include <linux/io.h> @@ -64,6 +63,7 @@ #define PLIC_QUIRK_EDGE_INTERRUPT 0 struct plic_priv { + struct device *dev; struct cpumask lmask; struct irq_domain *irqdomain; void __iomem *regs; @@ -371,7 +371,8 @@ static void plic_handle_irq(struct irq_desc *desc) int err = generic_handle_domain_irq(handler->priv->irqdomain, hwirq); if (unlikely(err)) - pr_warn_ratelimited("can't find mapping for hwirq %lu\n", + dev_warn_ratelimited(handler->priv->dev, + "can't find mapping for hwirq %lu\n", hwirq); } @@ -406,57 +407,126 @@ static int plic_starting_cpu(unsigned int cpu) return 0; } -static int __init __plic_init(struct device_node *node, - struct device_node *parent, - unsigned long plic_quirks) +static const struct of_device_id plic_match[] = { + { .compatible = "sifive,plic-1.0.0" }, + { .compatible = "riscv,plic0" }, + { .compatible = "andestech,nceplic100", + .data = (const void *)BIT(PLIC_QUIRK_EDGE_INTERRUPT) }, + { .compatible = "thead,c900-plic", + .data = (const void *)BIT(PLIC_QUIRK_EDGE_INTERRUPT) }, + {} +}; + +static int plic_parse_nr_irqs_and_contexts(struct platform_device *pdev, + u32 *nr_irqs, u32 *nr_contexts) { - int error = 0, nr_contexts, nr_handlers = 0, i; - u32 nr_irqs; - struct plic_priv *priv; + struct device *dev = &pdev->dev; + int rc; + + /* + * Currently, only OF fwnode is supported so extend this + * function for ACPI support. + */ + if (!is_of_node(dev->fwnode)) + return -EINVAL; + + rc = of_property_read_u32(to_of_node(dev->fwnode), + "riscv,ndev", nr_irqs); + if (rc) { + dev_err(dev, "riscv,ndev property not available\n"); + return rc; + } + + *nr_contexts = of_irq_count(to_of_node(dev->fwnode)); + if (WARN_ON(!(*nr_contexts))) { + dev_err(dev, "no PLIC context available\n"); + return -EINVAL; + } + + return 0; +} + +static int plic_parse_context_parent_hwirq(struct platform_device *pdev, + u32 context, u32 *parent_hwirq, + unsigned long *parent_hartid) +{ + struct device *dev = &pdev->dev; + struct of_phandle_args parent; + int rc; + + /* + * Currently, only OF fwnode is supported so extend this + * function for ACPI support. + */ + if (!is_of_node(dev->fwnode)) + return -EINVAL; + + rc = of_irq_parse_one(to_of_node(dev->fwnode), context, &parent); + if (rc) + return rc; + + rc = riscv_of_parent_hartid(parent.np, parent_hartid); + if (rc) + return rc; + + *parent_hwirq = parent.args[0]; + return 0; +} + +static int plic_probe(struct platform_device *pdev) +{ + int rc, nr_contexts, nr_handlers = 0, i, cpu; + unsigned long plic_quirks = 0, hartid; + struct device *dev = &pdev->dev; struct plic_handler *handler; - unsigned int cpu; + u32 nr_irqs, parent_hwirq; + struct irq_domain *domain; + struct plic_priv *priv; + irq_hw_number_t hwirq; + struct resource *res; + bool cpuhp_setup; + + if (is_of_node(dev->fwnode)) { + const struct of_device_id *id; + + id = of_match_node(plic_match, to_of_node(dev->fwnode)); + if (id) + plic_quirks = (unsigned long)id->data; + } - priv = kzalloc(sizeof(*priv), GFP_KERNEL); + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; - + priv->dev = dev; priv->plic_quirks = plic_quirks; - priv->regs = of_iomap(node, 0); - if (WARN_ON(!priv->regs)) { - error = -EIO; - goto out_free_priv; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(dev, "failed to get MMIO resource\n"); + return -EINVAL; + } + priv->regs = devm_ioremap(dev, res->start, resource_size(res)); + if (!priv->regs) { + dev_err(dev, "failed map MMIO registers\n"); + return -EIO; } - error = -EINVAL; - of_property_read_u32(node, "riscv,ndev", &nr_irqs); - if (WARN_ON(!nr_irqs)) - goto out_iounmap; - + rc = plic_parse_nr_irqs_and_contexts(pdev, &nr_irqs, &nr_contexts); + if (rc) { + dev_err(dev, "failed to parse irqs and contexts\n"); + return rc; + } priv->nr_irqs = nr_irqs; - priv->prio_save = bitmap_alloc(nr_irqs, GFP_KERNEL); + priv->prio_save = devm_bitmap_zalloc(dev, nr_irqs, GFP_KERNEL); if (!priv->prio_save) - goto out_free_priority_reg; - - nr_contexts = of_irq_count(node); - if (WARN_ON(!nr_contexts)) - goto out_free_priority_reg; - - error = -ENOMEM; - priv->irqdomain = irq_domain_add_linear(node, nr_irqs + 1, - &plic_irqdomain_ops, priv); - if (WARN_ON(!priv->irqdomain)) - goto out_free_priority_reg; + return -ENOMEM; for (i = 0; i < nr_contexts; i++) { - struct of_phandle_args parent; - irq_hw_number_t hwirq; - int cpu; - unsigned long hartid; - - if (of_irq_parse_one(node, i, &parent)) { - pr_err("failed to parse parent for context %d.\n", i); + rc = plic_parse_context_parent_hwirq(pdev, i, + &parent_hwirq, &hartid); + if (rc) { + dev_warn(dev, "hwirq for context%d not found\n", i); continue; } @@ -464,7 +534,7 @@ static int __init __plic_init(struct device_node *node, * Skip contexts other than external interrupts for our * privilege level. */ - if (parent.args[0] != RV_IRQ_EXT) { + if (parent_hwirq != RV_IRQ_EXT) { /* Disable S-mode enable bits if running in M-mode. */ if (IS_ENABLED(CONFIG_RISCV_M_MODE)) { void __iomem *enable_base = priv->regs + @@ -477,21 +547,17 @@ static int __init __plic_init(struct device_node *node, continue; } - error = riscv_of_parent_hartid(parent.np, &hartid); - if (error < 0) { - pr_warn("failed to parse hart ID for context %d.\n", i); - continue; - } - cpu = riscv_hartid_to_cpuid(hartid); if (cpu < 0) { - pr_warn("Invalid cpuid for context %d\n", i); + dev_warn(dev, "Invalid cpuid for context %d\n", i); continue; } /* Find parent domain and register chained handler */ - if (!plic_parent_irq && irq_find_host(parent.np)) { - plic_parent_irq = irq_of_parse_and_map(node, i); + domain = irq_find_matching_fwnode(riscv_get_intc_hwnode(), + DOMAIN_BUS_ANY); + if (!plic_parent_irq && domain) { + plic_parent_irq = irq_create_mapping(domain, RV_IRQ_EXT); if (plic_parent_irq) irq_set_chained_handler(plic_parent_irq, plic_handle_irq); @@ -504,7 +570,7 @@ static int __init __plic_init(struct device_node *node, */ handler = per_cpu_ptr(&plic_handlers, cpu); if (handler->present) { - pr_warn("handler already present for context %d.\n", i); + dev_warn(dev, "handler already present for context%d.\n", i); plic_set_threshold(handler, PLIC_DISABLE_THRESHOLD); goto done; } @@ -518,10 +584,15 @@ static int __init __plic_init(struct device_node *node, i * CONTEXT_ENABLE_SIZE; handler->priv = priv; - handler->enable_save = kcalloc(DIV_ROUND_UP(nr_irqs, 32), - sizeof(*handler->enable_save), GFP_KERNEL); - if (!handler->enable_save) - goto out_free_enable_reg; + handler->enable_save = devm_kcalloc(dev, + DIV_ROUND_UP(nr_irqs, 32), + sizeof(*handler->enable_save), + GFP_KERNEL); + if (!handler->enable_save) { + rc = -ENOMEM; + goto fail_cleanup_contexts; + } + done: for (hwirq = 1; hwirq <= nr_irqs; hwirq++) { plic_toggle(handler, hwirq, 0); @@ -531,52 +602,66 @@ static int __init __plic_init(struct device_node *node, nr_handlers++; } + priv->irqdomain = irq_domain_create_linear(dev->fwnode, nr_irqs + 1, + &plic_irqdomain_ops, priv); + if (WARN_ON(!priv->irqdomain)) { + rc = -ENOMEM; + goto fail_cleanup_contexts; + } + /* * We can have multiple PLIC instances so setup cpuhp state - * and register syscore operations only when context handler - * for current/boot CPU is present. + * and register syscore operations only once after context + * handlers of all online CPUs are initialized. */ - handler = this_cpu_ptr(&plic_handlers); - if (handler->present && !plic_cpuhp_setup_done) { - cpuhp_setup_state(CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING, - "irqchip/sifive/plic:starting", - plic_starting_cpu, plic_dying_cpu); - register_syscore_ops(&plic_irq_syscore_ops); - plic_cpuhp_setup_done = true; + if (!plic_cpuhp_setup_done) { + cpuhp_setup = true; + for_each_online_cpu(cpu) { + handler = per_cpu_ptr(&plic_handlers, cpu); + if (!handler->present) { + cpuhp_setup = false; + break; + } + } + if (cpuhp_setup) { + cpuhp_setup_state(CPUHP_AP_IRQ_SIFIVE_PLIC_STARTING, + "irqchip/sifive/plic:starting", + plic_starting_cpu, plic_dying_cpu); + register_syscore_ops(&plic_irq_syscore_ops); + plic_cpuhp_setup_done = true; + } } - pr_info("%pOFP: mapped %d interrupts with %d handlers for" - " %d contexts.\n", node, nr_irqs, nr_handlers, nr_contexts); + dev_info(dev, "mapped %d interrupts with %d handlers for %d contexts.\n", + nr_irqs, nr_handlers, nr_contexts); return 0; -out_free_enable_reg: - for_each_cpu(cpu, cpu_present_mask) { +fail_cleanup_contexts: + for (i = 0; i < nr_contexts; i++) { + if (plic_parse_context_parent_hwirq(pdev, i, + &parent_hwirq, &hartid)) + continue; + if (parent_hwirq != RV_IRQ_EXT) + continue; + cpu = riscv_hartid_to_cpuid(hartid); + if (cpu < 0) + continue; + handler = per_cpu_ptr(&plic_handlers, cpu); - kfree(handler->enable_save); + handler->present = false; + handler->hart_base = NULL; + handler->enable_base = NULL; + handler->enable_save = NULL; + handler->priv = NULL; } -out_free_priority_reg: - kfree(priv->prio_save); -out_iounmap: - iounmap(priv->regs); -out_free_priv: - kfree(priv); - return error; + return rc; } -static int __init plic_init(struct device_node *node, - struct device_node *parent) -{ - return __plic_init(node, parent, 0); -} - -IRQCHIP_DECLARE(sifive_plic, "sifive,plic-1.0.0", plic_init); -IRQCHIP_DECLARE(riscv_plic0, "riscv,plic0", plic_init); /* for legacy systems */ - -static int __init plic_edge_init(struct device_node *node, - struct device_node *parent) -{ - return __plic_init(node, parent, BIT(PLIC_QUIRK_EDGE_INTERRUPT)); -} - -IRQCHIP_DECLARE(andestech_nceplic100, "andestech,nceplic100", plic_edge_init); -IRQCHIP_DECLARE(thead_c900_plic, "thead,c900-plic", plic_edge_init); +static struct platform_driver plic_driver = { + .driver = { + .name = "riscv-plic", + .of_match_table = plic_match, + }, + .probe = plic_probe, +}; +builtin_platform_driver(plic_driver); -- 2.34.1