[PATCH v3 19/23] ACPI: RISC-V: Add RPMI System MSI to GSI mapping

Anup Patel
2025-05-11T13:42:46Z

From: Sunil V L <sunilvl@ventanamicro.com>

The RPMI System MSI device will provide GSIs to downstream devices
(such as GED) so add it to the RISC-V GSI to fwnode mapping.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
---
arch/riscv/include/asm/irq.h | 1 +
drivers/acpi/riscv/irq.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)

diff --git a/arch/riscv/include/asm/irq.h b/arch/riscv/include/asm/irq.h
index ef4aff62fba7..d28f90a25421 100644
--- a/arch/riscv/include/asm/irq.h
+++ b/arch/riscv/include/asm/irq.h
@@ -30,6 +30,7 @@ enum riscv_irqchip_type {
ACPI_RISCV_IRQCHIP_IMSIC = 0x01,
ACPI_RISCV_IRQCHIP_PLIC = 0x02,
ACPI_RISCV_IRQCHIP_APLIC = 0x03,
+ ACPI_RISCV_IRQCHIP_SMSI = 0x04,
};

int riscv_acpi_get_gsi_info(struct fwnode_handle *fwnode, u32 *gsi_base,
diff --git a/drivers/acpi/riscv/irq.c b/drivers/acpi/riscv/irq.c
index 2ce311042627..42f79940a69d 100644
--- a/drivers/acpi/riscv/irq.c
+++ b/drivers/acpi/riscv/irq.c
@@ -173,6 +173,33 @@ static int __init riscv_acpi_register_ext_intc(u32 gsi_base, u32 nr_irqs, u32 nr
return 0;
}

+static acpi_status __init riscv_acpi_create_gsi_map_smsi(acpi_handle handle, u32 level,
+ void *context, void **return_value)
+{
+ acpi_status status;
+ u64 gbase;
+
+ if (!acpi_has_method(handle, "_GSB")) {
+ acpi_handle_err(handle, "_GSB method not found\n");
+ return AE_ERROR;
+ }
+
+ status = acpi_evaluate_integer(handle, "_GSB", NULL, &gbase);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_err(handle, "failed to evaluate _GSB method\n");
+ return status;
+ }
+
+ riscv_acpi_register_ext_intc(gbase, 0, 0, 0, ACPI_RISCV_IRQCHIP_SMSI);
+ status = riscv_acpi_update_gsi_handle((u32)gbase, handle);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_err(handle, "failed to find the GSI mapping entry\n");
+ return status;
+ }
+
+ return AE_OK;
+}
+
static acpi_status __init riscv_acpi_create_gsi_map(acpi_handle handle, u32 level,
void *context, void **return_value)
{
@@ -227,6 +254,9 @@ void __init riscv_acpi_init_gsi_mapping(void)

if (acpi_table_parse_madt(ACPI_MADT_TYPE_APLIC, riscv_acpi_aplic_parse_madt, 0) > 0)
acpi_get_devices("RSCV0002", riscv_acpi_create_gsi_map, NULL, NULL);
+
+ /* Unlike PLIC/APLIC, SYSMSI doesn't have MADT */
+ acpi_get_devices("RSCV0006", riscv_acpi_create_gsi_map_smsi, NULL, NULL);
}

static acpi_handle riscv_acpi_get_gsi_handle(u32 gsi)
--
2.43.0