[PATCH 10/24] ACPI: processor_core: RISC-V: Enable mapping processor to the hartid

Sunil V L
2023-01-30T18:24:27Z

processor_core needs arch specific functions to map the ACPI ID
to the physical ID. In RISC-V platforms, hartid is the physical id
and RINTC structure in MADT provides this mapping. Add arch specific
function to get this mapping from RINTC.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
---
arch/riscv/include/asm/acpi.h | 3 +++
drivers/acpi/processor_core.c | 28 ++++++++++++++++++++++++++++
2 files changed, 31 insertions(+)

diff --git a/arch/riscv/include/asm/acpi.h b/arch/riscv/include/asm/acpi.h
index 8b9babaf3f25..c5cb9f96d404 100644
--- a/arch/riscv/include/asm/acpi.h
+++ b/arch/riscv/include/asm/acpi.h
@@ -15,6 +15,9 @@
/* Basic configuration for ACPI */
#ifdef CONFIG_ACPI

+typedef u64 phys_cpuid_t;
+#define PHYS_CPUID_INVALID INVALID_HARTID
+
/* ACPI table mapping after acpi_permanent_mmap is set */
void *acpi_os_ioremap(acpi_physical_address phys, acpi_size size);
#define acpi_os_ioremap acpi_os_ioremap
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 2ac48cda5b20..889f495b3481 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -106,6 +106,31 @@ static int map_gicc_mpidr(struct acpi_subtable_header *entry,
return -EINVAL;
}

+/*
+ * Retrieve the RISC-V hartid for the processor
+ */
+static int map_rintc_hartid(struct acpi_subtable_header *entry,
+ int device_declaration, u32 acpi_id, phys_cpuid_t *hartid)
+{
+ struct acpi_madt_rintc *rintc =
+ container_of(entry, struct acpi_madt_rintc, header);
+
+ if (!(rintc->flags & ACPI_MADT_ENABLED))
+ return -ENODEV;
+
+ /* device_declaration means Device object in DSDT, in the
+ * RISC-V, logical processors are required to
+ * have a Processor Device object in the DSDT, so we should
+ * check device_declaration here
+ */
+ if (device_declaration && (rintc->uid == acpi_id)) {
+ *hartid = rintc->hart_id;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
int type, u32 acpi_id)
{
@@ -136,6 +161,9 @@ static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
break;
+ } else if (header->type == ACPI_MADT_TYPE_RINTC) {
+ if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
+ break;
}
entry += header->length;
}
--
2.38.0