The following commit has been merged into the irq/urgent branch of tip:

Commit-ID: 4d936f10ff80274841537a26d1fbfe9984de0ef9 Gitweb: https://git.kernel.org/tip/4d936f10ff80274841537a26d1fbfe9984de0ef9 Author: Anup Patel apatel@ventanamicro.com AuthorDate: Tue, 20 Aug 2024 09:18:50 +05:30 Committer: Thomas Gleixner tglx@linutronix.de CommitterDate: Tue, 20 Aug 2024 16:45:20 +02:00

irqchip/sifive-plic: Probe plic driver early for Allwinner D1 platform

The latest Linux RISC-V no longer boots on the Allwinner D1 platform because the sun4i_timer driver fails to get an interrupt from PLIC due to the recent conversion of the PLIC to a platform driver. Converting the sun4i timer to a platform driver does not work either because the D1 does not have a SBI timer available so early boot hangs. See the 'Closes:' link for deeper analysis.

The real fix requires enabling the SBI time extension in the platform firmware (OpenSBI) and convert sun4i_timer into platform driver. Unfortunately, the real fix involves changing multiple places and can't be achieved in a short duration and aside of that requires users to update firmware.

As a work-around, retrofit PLIC probing such that the PLIC is probed early only for the Allwinner D1 platform and probed as a regular platform driver for rest of the RISC-V platforms. In the process, partially revert some of the previous changes because the PLIC device pointer is not available in all probing paths.

Fixes: e306a894bd51 ("irqchip/sifive-plic: Chain to parent IRQ after handlers are ready") Fixes: 8ec99b033147 ("irqchip/sifive-plic: Convert PLIC driver into a platform driver") Suggested-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Anup Patel apatel@ventanamicro.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Tested-by: Samuel Holland samuel.holland@sifive.com Tested-by: Emil Renner Berthing emil.renner.berthing@canonical.com Tested-by: Charlie Jenkins charlie@rivosinc.com Reviewed-by: Samuel Holland samuel.holland@sifive.com Reviewed-by: Charlie Jenkins charlie@rivosinc.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240820034850.3189912-1-apatel@ventanamicro.com Closes: https://lore.kernel.org/lkml/20240814145642.344485-1-emil.renner.berthing@ca... --- drivers/irqchip/irq-sifive-plic.c | 115 +++++++++++++++++------------ 1 file changed, 71 insertions(+), 44 deletions(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c index 9e22f7e..4d9ea71 100644 --- a/drivers/irqchip/irq-sifive-plic.c +++ b/drivers/irqchip/irq-sifive-plic.c @@ -3,6 +3,7 @@ * Copyright (C) 2017 SiFive * Copyright (C) 2018 Christoph Hellwig */ +#define pr_fmt(fmt) "riscv-plic: " fmt #include <linux/cpu.h> #include <linux/interrupt.h> #include <linux/io.h> @@ -63,7 +64,7 @@ #define PLIC_QUIRK_EDGE_INTERRUPT 0

struct plic_priv { - struct device *dev; + struct fwnode_handle *fwnode; struct cpumask lmask; struct irq_domain *irqdomain; void __iomem *regs; @@ -378,8 +379,8 @@ static void plic_handle_irq(struct irq_desc *desc) int err = generic_handle_domain_irq(handler->priv->irqdomain, hwirq); if (unlikely(err)) { - dev_warn_ratelimited(handler->priv->dev, - "can't find mapping for hwirq %lu\n", hwirq); + pr_warn_ratelimited("%pfwP: can't find mapping for hwirq %lu\n", + handler->priv->fwnode, hwirq); } }

@@ -408,7 +409,8 @@ static int plic_starting_cpu(unsigned int cpu) enable_percpu_irq(plic_parent_irq, irq_get_trigger_type(plic_parent_irq)); else - dev_warn(handler->priv->dev, "cpu%d: parent irq not available\n", cpu); + pr_warn("%pfwP: cpu%d: parent irq not available\n", + handler->priv->fwnode, cpu); plic_set_threshold(handler, PLIC_ENABLE_THRESHOLD);

return 0; @@ -424,38 +426,36 @@ static const struct of_device_id plic_match[] = { {} };

-static int plic_parse_nr_irqs_and_contexts(struct platform_device *pdev, +static int plic_parse_nr_irqs_and_contexts(struct fwnode_handle *fwnode, u32 *nr_irqs, u32 *nr_contexts) { - 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)) + if (!is_of_node(fwnode)) return -EINVAL;

- rc = of_property_read_u32(to_of_node(dev->fwnode), "riscv,ndev", nr_irqs); + rc = of_property_read_u32(to_of_node(fwnode), "riscv,ndev", nr_irqs); if (rc) { - dev_err(dev, "riscv,ndev property not available\n"); + pr_err("%pfwP: riscv,ndev property not available\n", fwnode); return rc; }

- *nr_contexts = of_irq_count(to_of_node(dev->fwnode)); + *nr_contexts = of_irq_count(to_of_node(fwnode)); if (WARN_ON(!(*nr_contexts))) { - dev_err(dev, "no PLIC context available\n"); + pr_err("%pfwP: no PLIC context available\n", fwnode); return -EINVAL; }

return 0; }

-static int plic_parse_context_parent(struct platform_device *pdev, u32 context, +static int plic_parse_context_parent(struct fwnode_handle *fwnode, u32 context, u32 *parent_hwirq, int *parent_cpu) { - struct device *dev = &pdev->dev; struct of_phandle_args parent; unsigned long hartid; int rc; @@ -464,10 +464,10 @@ static int plic_parse_context_parent(struct platform_device *pdev, u32 context, * Currently, only OF fwnode is supported so extend this * function for ACPI support. */ - if (!is_of_node(dev->fwnode)) + if (!is_of_node(fwnode)) return -EINVAL;

- rc = of_irq_parse_one(to_of_node(dev->fwnode), context, &parent); + rc = of_irq_parse_one(to_of_node(fwnode), context, &parent); if (rc) return rc;

@@ -480,48 +480,55 @@ static int plic_parse_context_parent(struct platform_device *pdev, u32 context, return 0; }

-static int plic_probe(struct platform_device *pdev) +static int plic_probe(struct fwnode_handle *fwnode) { int error = 0, nr_contexts, nr_handlers = 0, cpu, i; - struct device *dev = &pdev->dev; unsigned long plic_quirks = 0; struct plic_handler *handler; u32 nr_irqs, parent_hwirq; struct plic_priv *priv; irq_hw_number_t hwirq; + void __iomem *regs;

- if (is_of_node(dev->fwnode)) { + if (is_of_node(fwnode)) { const struct of_device_id *id;

- id = of_match_node(plic_match, to_of_node(dev->fwnode)); + id = of_match_node(plic_match, to_of_node(fwnode)); if (id) plic_quirks = (unsigned long)id->data; + + regs = of_iomap(to_of_node(fwnode), 0); + if (!regs) + return -ENOMEM; + } else { + return -ENODEV; }

- error = plic_parse_nr_irqs_and_contexts(pdev, &nr_irqs, &nr_contexts); + error = plic_parse_nr_irqs_and_contexts(fwnode, &nr_irqs, &nr_contexts); if (error) - return error; + goto fail_free_regs;

- priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); - if (!priv) - return -ENOMEM; + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) { + error = -ENOMEM; + goto fail_free_regs; + }

- priv->dev = dev; + priv->fwnode = fwnode; priv->plic_quirks = plic_quirks; priv->nr_irqs = nr_irqs; + priv->regs = regs;

- priv->regs = devm_platform_ioremap_resource(pdev, 0); - if (WARN_ON(!priv->regs)) - return -EIO; - - priv->prio_save = devm_bitmap_zalloc(dev, nr_irqs, GFP_KERNEL); - if (!priv->prio_save) - return -ENOMEM; + priv->prio_save = bitmap_zalloc(nr_irqs, GFP_KERNEL); + if (!priv->prio_save) { + error = -ENOMEM; + goto fail_free_priv; + }

for (i = 0; i < nr_contexts; i++) { - error = plic_parse_context_parent(pdev, i, &parent_hwirq, &cpu); + error = plic_parse_context_parent(fwnode, i, &parent_hwirq, &cpu); if (error) { - dev_warn(dev, "hwirq for context%d not found\n", i); + pr_warn("%pfwP: hwirq for context%d not found\n", fwnode, i); continue; }

@@ -543,7 +550,7 @@ static int plic_probe(struct platform_device *pdev) }

if (cpu < 0) { - dev_warn(dev, "Invalid cpuid for context %d\n", i); + pr_warn("%pfwP: Invalid cpuid for context %d\n", fwnode, i); continue; }

@@ -554,7 +561,7 @@ static int plic_probe(struct platform_device *pdev) */ handler = per_cpu_ptr(&plic_handlers, cpu); if (handler->present) { - dev_warn(dev, "handler already present for context %d.\n", i); + pr_warn("%pfwP: handler already present for context %d.\n", fwnode, i); plic_set_threshold(handler, PLIC_DISABLE_THRESHOLD); goto done; } @@ -568,8 +575,8 @@ static int plic_probe(struct platform_device *pdev) i * CONTEXT_ENABLE_SIZE; handler->priv = priv;

- handler->enable_save = devm_kcalloc(dev, DIV_ROUND_UP(nr_irqs, 32), - sizeof(*handler->enable_save), GFP_KERNEL); + handler->enable_save = kcalloc(DIV_ROUND_UP(nr_irqs, 32), + sizeof(*handler->enable_save), GFP_KERNEL); if (!handler->enable_save) goto fail_cleanup_contexts; done: @@ -581,7 +588,7 @@ done: nr_handlers++; }

- priv->irqdomain = irq_domain_add_linear(to_of_node(dev->fwnode), nr_irqs + 1, + priv->irqdomain = irq_domain_add_linear(to_of_node(fwnode), nr_irqs + 1, &plic_irqdomain_ops, priv); if (WARN_ON(!priv->irqdomain)) goto fail_cleanup_contexts; @@ -619,13 +626,13 @@ done: } }

- dev_info(dev, "mapped %d interrupts with %d handlers for %d contexts.\n", - nr_irqs, nr_handlers, nr_contexts); + pr_info("%pfwP: mapped %d interrupts with %d handlers for %d contexts.\n", + fwnode, nr_irqs, nr_handlers, nr_contexts); return 0;

fail_cleanup_contexts: for (i = 0; i < nr_contexts; i++) { - if (plic_parse_context_parent(pdev, i, &parent_hwirq, &cpu)) + if (plic_parse_context_parent(fwnode, i, &parent_hwirq, &cpu)) continue; if (parent_hwirq != RV_IRQ_EXT || cpu < 0) continue; @@ -634,17 +641,37 @@ fail_cleanup_contexts: handler->present = false; handler->hart_base = NULL; handler->enable_base = NULL; + kfree(handler->enable_save); handler->enable_save = NULL; handler->priv = NULL; } - return -ENOMEM; + bitmap_free(priv->prio_save); +fail_free_priv: + kfree(priv); +fail_free_regs: + iounmap(regs); + return error; +} + +static int plic_platform_probe(struct platform_device *pdev) +{ + return plic_probe(pdev->dev.fwnode); }

static struct platform_driver plic_driver = { .driver = { .name = "riscv-plic", .of_match_table = plic_match, + .suppress_bind_attrs = true, }, - .probe = plic_probe, + .probe = plic_platform_probe, }; builtin_platform_driver(plic_driver); + +static int __init plic_early_probe(struct device_node *node, + struct device_node *parent) +{ + return plic_probe(&node->fwnode); +} + +IRQCHIP_DECLARE(riscv, "allwinner,sun20i-d1-plic", plic_early_probe);