[PATCH v5 16/17] irqchip/sifive-plic: Add ACPI support

Sunil V L
2024-05-01T12:20:08Z

Add ACPI support in PLIC driver. Use the mapping created early during
boot to get details about the PLIC.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Co-developed-by: Haibo Xu <haibo1.xu@intel.com>
Signed-off-by: Haibo Xu <haibo1.xu@intel.com>
---
drivers/irqchip/irq-sifive-plic.c | 89 +++++++++++++++++++++++--------
1 file changed, 68 insertions(+), 21 deletions(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 8fb183ced1e7..b6b04b5923c2 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
*/
+#include <linux/acpi.h>
#include <linux/cpu.h>
#include <linux/interrupt.h>
#include <linux/io.h>
@@ -70,6 +71,8 @@ struct plic_priv {
unsigned long plic_quirks;
unsigned int nr_irqs;
unsigned long *prio_save;
+ u32 gsi_base;
+ int id;
};

struct plic_handler {
@@ -324,6 +327,10 @@ static int plic_irq_domain_translate(struct irq_domain *d,
{
struct plic_priv *priv = d->host_data;

+ /* For DT, gsi_base is always zero. */
+ if (fwspec->param[0] >= priv->gsi_base)
+ fwspec->param[0] = fwspec->param[0] - priv->gsi_base;
+
if (test_bit(PLIC_QUIRK_EDGE_INTERRUPT, &priv->plic_quirks))
return irq_domain_translate_twocell(d, fwspec, hwirq, type);

@@ -424,18 +431,32 @@ static const struct of_device_id plic_match[] = {
{}
};

+#ifdef CONFIG_ACPI
+
+static const struct acpi_device_id plic_acpi_match[] = {
+ { "RSCV0001", 0 },
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, plic_acpi_match);
+
+#endif
static int plic_parse_nr_irqs_and_contexts(struct platform_device *pdev,
- u32 *nr_irqs, u32 *nr_contexts)
+ u32 *nr_irqs, u32 *nr_contexts,
+ u32 *gsi_base, u32 *id)
{
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;
+ if (!is_of_node(dev->fwnode)) {
+ riscv_acpi_get_gsi_info(dev->fwnode, gsi_base, id, nr_irqs, NULL);
+ acpi_get_plic_nr_contexts(*id, nr_contexts);
+ if (WARN_ON(!*nr_contexts)) {
+ dev_err(dev, "no PLIC context available\n");
+ return -EINVAL;
+ }
+
+ return 0;
+ }

rc = of_property_read_u32(to_of_node(dev->fwnode), "riscv,ndev", nr_irqs);
if (rc) {
@@ -449,23 +470,29 @@ static int plic_parse_nr_irqs_and_contexts(struct platform_device *pdev,
return -EINVAL;
}

+ *gsi_base = 0;
+ *id = 0;
+
return 0;
}

static int plic_parse_context_parent(struct platform_device *pdev, u32 context,
- u32 *parent_hwirq, int *parent_cpu)
+ u32 *parent_hwirq, int *parent_cpu, u32 id)
{
struct device *dev = &pdev->dev;
struct of_phandle_args parent;
unsigned long hartid;
int rc;

- /*
- * Currently, only OF fwnode is supported so extend this
- * function for ACPI support.
- */
- if (!is_of_node(dev->fwnode))
- return -EINVAL;
+ if (!is_of_node(dev->fwnode)) {
+ rc = acpi_get_ext_intc_parent_hartid(id, context, &hartid);
+ if (rc)
+ return rc;
+
+ *parent_cpu = riscv_hartid_to_cpuid(hartid);
+ *parent_hwirq = RV_IRQ_EXT;
+ return 0;
+ }

rc = of_irq_parse_one(to_of_node(dev->fwnode), context, &parent);
if (rc)
@@ -490,7 +517,9 @@ static int plic_probe(struct platform_device *pdev)
struct irq_domain *domain;
struct plic_priv *priv;
irq_hw_number_t hwirq;
+ int id, context_id;
bool cpuhp_setup;
+ u32 gsi_base;

if (is_of_node(dev->fwnode)) {
const struct of_device_id *id;
@@ -500,7 +529,7 @@ static int plic_probe(struct platform_device *pdev)
plic_quirks = (unsigned long)id->data;
}

- error = plic_parse_nr_irqs_and_contexts(pdev, &nr_irqs, &nr_contexts);
+ error = plic_parse_nr_irqs_and_contexts(pdev, &nr_irqs, &nr_contexts, &gsi_base, &id);
if (error)
return error;

@@ -511,6 +540,8 @@ static int plic_probe(struct platform_device *pdev)
priv->dev = dev;
priv->plic_quirks = plic_quirks;
priv->nr_irqs = nr_irqs;
+ priv->gsi_base = gsi_base;
+ priv->id = id;

priv->regs = devm_platform_ioremap_resource(pdev, 0);
if (WARN_ON(!priv->regs))
@@ -521,12 +552,22 @@ static int plic_probe(struct platform_device *pdev)
return -ENOMEM;

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

+ if (is_of_node(dev->fwnode)) {
+ context_id = i;
+ } else {
+ error = acpi_get_plic_context(priv->id, i, &context_id);
+ if (error) {
+ dev_warn(dev, "invalid context id for context%d\n", i);
+ continue;
+ }
+ }
+
/*
* Skip contexts other than external interrupts for our
* privilege level.
@@ -572,10 +613,10 @@ static int plic_probe(struct platform_device *pdev)
cpumask_set_cpu(cpu, &priv->lmask);
handler->present = true;
handler->hart_base = priv->regs + CONTEXT_BASE +
- i * CONTEXT_SIZE;
+ context_id * CONTEXT_SIZE;
raw_spin_lock_init(&handler->enable_lock);
handler->enable_base = priv->regs + CONTEXT_ENABLE_BASE +
- i * CONTEXT_ENABLE_SIZE;
+ context_id * CONTEXT_ENABLE_SIZE;
handler->priv = priv;

handler->enable_save = devm_kcalloc(dev, DIV_ROUND_UP(nr_irqs, 32),
@@ -591,8 +632,8 @@ static int plic_probe(struct platform_device *pdev)
nr_handlers++;
}

- priv->irqdomain = irq_domain_add_linear(to_of_node(dev->fwnode), nr_irqs + 1,
- &plic_irqdomain_ops, priv);
+ priv->irqdomain = irq_domain_create_linear(dev->fwnode, nr_irqs + 1,
+ &plic_irqdomain_ops, priv);
if (WARN_ON(!priv->irqdomain))
goto fail_cleanup_contexts;

@@ -619,13 +660,18 @@ static int plic_probe(struct platform_device *pdev)
}
}

+#ifdef CONFIG_ACPI
+ if (!acpi_disabled)
+ acpi_dev_clear_dependencies(ACPI_COMPANION(dev));
+#endif
+
dev_info(dev, "mapped %d interrupts with %d handlers for %d contexts.\n",
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(pdev, i, &parent_hwirq, &cpu, priv->id))
continue;
if (parent_hwirq != RV_IRQ_EXT || cpu < 0)
continue;
@@ -644,6 +690,7 @@ static struct platform_driver plic_driver = {
.driver = {
.name = "riscv-plic",
.of_match_table = plic_match,
+ .acpi_match_table = ACPI_PTR(plic_acpi_match),
},
.probe = plic_probe,
};
--
2.40.1