soc/amd/common/block/acpi/cpu_power_state: introduce get_cstate_io_base
Introduce the get_cstate_io_base helper function that write_cstate_entry
can call directly to get the C state control IO base address instead of
having get_cstate_info pass this Io address to each write_cstate_entry
call.
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Suggested-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Change-Id: I4cc80ded0a2fbc2dee9ca819e86284d9ffd58685
Reviewed-on: https://review.coreboot.org/c/coreboot/+/73533
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/soc/amd/common/block/acpi/cpu_power_state.c b/src/soc/amd/common/block/acpi/cpu_power_state.c
index 9eb636d..24b08f0 100644
--- a/src/soc/amd/common/block/acpi/cpu_power_state.c
+++ b/src/soc/amd/common/block/acpi/cpu_power_state.c
@@ -51,8 +51,19 @@
return pstate_count;
}
-static void write_cstate_entry(acpi_cstate_t *entry, const acpi_cstate_t *data,
- uint32_t cstate_io_base_address)
+static uint16_t get_cstate_io_base_address(void)
+{
+ static uint16_t cstate_io_base;
+
+ if (cstate_io_base)
+ return cstate_io_base;
+
+ cstate_io_base = rdmsr(MSR_CSTATE_ADDRESS).lo & MSR_CSTATE_ADDRESS_MASK;
+
+ return cstate_io_base;
+}
+
+static void write_cstate_entry(acpi_cstate_t *entry, const acpi_cstate_t *data)
{
if (!data->ctype) {
printk(BIOS_WARNING, "Invalid C-state data; skipping entry.\n");
@@ -76,9 +87,9 @@
.space_id = ACPI_ADDRESS_SPACE_IO,
.bit_width = 8,
.bit_offset = 0,
- /* ctype is 1-indexed while the offset into cstate_io_base_address is
- 0-indexed */
- .addrl = cstate_io_base_address + data->ctype - 1,
+ /* ctype is 1-indexed while the offset into the IO address returned by
+ get_cstate_io_base_address() is 0-indexed */
+ .addrl = get_cstate_io_base_address() + data->ctype - 1,
.addrh = 0,
.access_size = ACPI_ACCESS_SIZE_BYTE_ACCESS,
};
@@ -89,8 +100,6 @@
{
size_t i;
size_t cstate_count;
- uint32_t cstate_io_base_address =
- rdmsr(MSR_CSTATE_ADDRESS).lo & MSR_CSTATE_ADDRESS_MASK;
const acpi_cstate_t *cstate_config = get_cstate_config_data(&cstate_count);
if (cstate_count > MAX_CSTATE_COUNT) {
@@ -101,7 +110,7 @@
}
for (i = 0; i < cstate_count; i++) {
- write_cstate_entry(&cstate_values[i], &cstate_config[i], cstate_io_base_address);
+ write_cstate_entry(&cstate_values[i], &cstate_config[i]);
}
return i;