[PATCH v6 13/17] irqchip/riscv-intc: Add ACPI support for AIA

Sunil V L
2024-06-01T15:05:54Z

The RINTC subtype structure in MADT also has information about other
interrupt controllers. Save this information and provide interfaces to
retrieve them when required by corresponding drivers.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
---
arch/riscv/include/asm/irq.h | 33 ++++++++++++
drivers/irqchip/irq-riscv-intc.c | 90 ++++++++++++++++++++++++++++++++
2 files changed, 123 insertions(+)

diff --git a/arch/riscv/include/asm/irq.h b/arch/riscv/include/asm/irq.h
index 44a0b128c602..51d86f0b80d2 100644
--- a/arch/riscv/include/asm/irq.h
+++ b/arch/riscv/include/asm/irq.h
@@ -12,6 +12,8 @@

#include <asm-generic/irq.h>

+#define INVALID_CONTEXT UINT_MAX
+
void riscv_set_intc_hwnode_fn(struct fwnode_handle *(*fn)(void));

struct fwnode_handle *riscv_get_intc_hwnode(void);
@@ -28,6 +30,11 @@ enum riscv_irqchip_type {
int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
u32 *id, u32 *nr_irqs, u32 *nr_idcs);
struct fwnode_handle *riscv_acpi_get_gsi_domain_id(u32 gsi);
+unsigned long acpi_get_intc_index_hartid(u32 index);
+unsigned long acpi_get_ext_intc_parent_hartid(unsigned int plic_id, unsigned int ctxt_idx);
+unsigned int acpi_get_plic_nr_contexts(unsigned int plic_id);
+unsigned int acpi_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx);
+int __init acpi_get_imsic_mmio_info(u32 index, struct resource *res);

#else
static inline int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
@@ -36,6 +43,32 @@ static inline int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi
return 0;
}

+static inline unsigned long acpi_get_intc_index_hartid(u32 index)
+{
+ return INVALID_HARTID;
+}
+
+static inline unsigned long acpi_get_ext_intc_parent_hartid(unsigned int plic_id,
+ unsigned int ctxt_idx)
+{
+ return INVALID_HARTID;
+}
+
+static inline unsigned int acpi_get_plic_nr_contexts(unsigned int plic_id)
+{
+ return INVALID_CONTEXT;
+}
+
+static inline unsigned int acpi_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx)
+{
+ return INVALID_CONTEXT;
+}
+
+static inline int __init acpi_get_imsic_mmio_info(u32 index, struct resource *res)
+{
+ return 0;
+}
+
#endif /* CONFIG_ACPI */

#endif /* _ASM_RISCV_IRQ_H */
diff --git a/drivers/irqchip/irq-riscv-intc.c b/drivers/irqchip/irq-riscv-intc.c
index 4f3a12383a1e..3c6494f1cb02 100644
--- a/drivers/irqchip/irq-riscv-intc.c
+++ b/drivers/irqchip/irq-riscv-intc.c
@@ -250,6 +250,85 @@ IRQCHIP_DECLARE(andes, "andestech,cpu-intc", riscv_intc_init);

#ifdef CONFIG_ACPI

+struct rintc_data {
+ union {
+ u32 ext_intc_id;
+ struct {
+ u32 context_id : 16,
+ reserved : 8,
+ aplic_plic_id : 8;
+ };
+ };
+ unsigned long hart_id;
+ u64 imsic_addr;
+ u32 imsic_size;
+};
+
+static u32 nr_rintc;
+static struct rintc_data *rintc_acpi_data[NR_CPUS];
+
+#define for_each_matching_plic(_plic_id) \
+ unsigned int _plic; \
+ \
+ for (_plic = 0; _plic < nr_rintc; _plic++) \
+ if (rintc_acpi_data[_plic]->aplic_plic_id != _plic_id) \
+ continue; \
+ else
+
+unsigned int acpi_get_plic_nr_contexts(unsigned int plic_id)
+{
+ unsigned int nctx = 0;
+
+ for_each_matching_plic(plic_id)
+ nctx++;
+
+ return nctx;
+}
+
+static struct rintc_data *get_plic_context(unsigned int plic_id, unsigned int ctxt_idx)
+{
+ unsigned int ctxt = 0;
+
+ for_each_matching_plic(plic_id) {
+ if (ctxt == ctxt_idx)
+ return rintc_acpi_data[_plic];
+
+ ctxt++;
+ }
+
+ return NULL;
+}
+
+unsigned long acpi_get_ext_intc_parent_hartid(unsigned int plic_id, unsigned int ctxt_idx)
+{
+ struct rintc_data *data = get_plic_context(plic_id, ctxt_idx);
+
+ return data ? data->hart_id : INVALID_HARTID;
+}
+
+unsigned int acpi_get_plic_context(unsigned int plic_id, unsigned int ctxt_idx)
+{
+ struct rintc_data *data = get_plic_context(plic_id, ctxt_idx);
+
+ return data ? data->context_id : INVALID_CONTEXT;
+}
+
+unsigned long acpi_get_intc_index_hartid(u32 index)
+{
+ return index >= nr_rintc ? INVALID_HARTID : rintc_acpi_data[index]->hart_id;
+}
+
+int acpi_get_imsic_mmio_info(u32 index, struct resource *res)
+{
+ if (index >= nr_rintc)
+ return -1;
+
+ res->start = rintc_acpi_data[index]->imsic_addr;
+ res->end = res->start + rintc_acpi_data[index]->imsic_size - 1;
+ res->flags = IORESOURCE_MEM;
+ return 0;
+}
+
static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header,
const unsigned long end)
{
@@ -258,6 +337,15 @@ static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header,
int rc;

rintc = (struct acpi_madt_rintc *)header;
+ rintc_acpi_data[nr_rintc] = kzalloc(sizeof(*rintc_acpi_data[0]), GFP_KERNEL);
+ if (!rintc_acpi_data[nr_rintc])
+ return -ENOMEM;
+
+ rintc_acpi_data[nr_rintc]->ext_intc_id = rintc->ext_intc_id;
+ rintc_acpi_data[nr_rintc]->hart_id = rintc->hart_id;
+ rintc_acpi_data[nr_rintc]->imsic_addr = rintc->imsic_addr;
+ rintc_acpi_data[nr_rintc]->imsic_size = rintc->imsic_size;
+ nr_rintc++;

/*
* The ACPI MADT will have one INTC for each CPU (or HART)
@@ -277,6 +365,8 @@ static int __init riscv_intc_acpi_init(union acpi_subtable_headers *header,
rc = riscv_intc_init_common(fn, &riscv_intc_chip);
if (rc)
irq_domain_free_fwnode(fn);
+ else
+ acpi_set_irq_model(ACPI_IRQ_MODEL_RINTC, riscv_acpi_get_gsi_domain_id);

return rc;
}
--
2.40.1