[PATCH v3] irqchip/sifive-plic: Probe plic driver early for Allwinner D1 platform
Anup Patel
apatel at ventanamicro.com
Mon Aug 19 20:48:50 PDT 2024
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.
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.
As a work-around, retrofit plic probing such that 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 patches because PLIC device
pointer is not available in all probing paths.
More detailed discussion can found here:
https://lore.kernel.org/lkml/20240814145642.344485-1-emil.renner.berthing@canonical.com/
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 at linutronix.de>
Reviewed-by: Samuel Holland <samuel.holland at sifive.com>
Tested-by: Samuel Holland <samuel.holland at sifive.com>
Tested-by: Emil Renner Berthing <emil.renner.berthing at canonical.com>
Reviewed-by: Charlie Jenkins <charlie at rivosinc.com>
Tested-by: Charlie Jenkins <charlie at rivosinc.com>
Signed-off-by: Anup Patel <apatel at ventanamicro.com>
---
Changes since v2:
- Use SoC specific PLIC compatible string for Allwinner D1
Changes since v1:
- Set suppress_bind_attrs for PLIC platform driver
---
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 9e22f7e378f5..4d9ea718086d 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 @@ static int plic_probe(struct platform_device *pdev)
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 @@ static int plic_probe(struct platform_device *pdev)
}
}
- 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 @@ static int plic_probe(struct platform_device *pdev)
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);
--
2.34.1
More information about the linux-riscv
mailing list