lenovo/x60: CST table: use MWAIT requests instead of P_LVLx I/O reads
Requesting low power acpi cpu c-states has two software interfaces:
Using P_LVLx I/O reads or using equivalent MWAIT requests.
This change makes it more consistent with newer targets that use MWAIT
requests.
There also exists extended intel acpi c-states which can be enabled
in two ways:
- using a substate hint to the mwait request (defined in bios);
- setting a model specific register (msr)
Currently this is done by setting the right msr bits but with this
change one can experiment by adding substate hints.
Change-Id: I9eeb5b008e2ddc2193725667f2c13582a4877e3c
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/14801
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
diff --git a/src/mainboard/lenovo/x60/mainboard.c b/src/mainboard/lenovo/x60/mainboard.c
index 5ea4221..b1096d2 100644
--- a/src/mainboard/lenovo/x60/mainboard.c
+++ b/src/mainboard/lenovo/x60/mainboard.c
@@ -38,10 +38,37 @@
#define PANEL INT15_5F35_CL_DISPLAY_DEFAULT
+#define MWAIT_RES(state, sub_state) \
+ { \
+ .space_id = ACPI_ADDRESS_SPACE_FIXED, \
+ .bit_width = ACPI_FFIXEDHW_VENDOR_INTEL, \
+ .bit_offset = ACPI_FFIXEDHW_CLASS_MWAIT, \
+ { \
+ .resv = 0, \
+ }, \
+ .addrl = (((state) << 4) | (sub_state)), \
+ .addrh = 0, \
+ }
+
static acpi_cstate_t cst_entries[] = {
- { 1, 1, 1000, { 0x7f, 1, 2, { 0 }, 1, 0 } },
- { 2, 1, 500, { 0x01, 8, 0, { 0 }, DEFAULT_PMBASE + LV2, 0 } },
- { 2, 17, 250, { 0x01, 8, 0, { 0 }, DEFAULT_PMBASE + LV3, 0 } },
+ {
+ .ctype = 1,
+ .latency = 1,
+ .power = 1000,
+ .resource = MWAIT_RES(0, 0),
+ },
+ {
+ .ctype = 2,
+ .latency = 1,
+ .power = 500,
+ .resource = MWAIT_RES(1, 0),
+ },
+ {
+ .ctype = 3,
+ .latency = 17,
+ .power = 250,
+ .resource = MWAIT_RES(2, 0),
+ },
};
int get_cst_entries(acpi_cstate_t **entries)