[S] Change in coreboot[master]: acpigen: Add a runtime method to override exposed _Sx sleep states

[Lean Sheng Tan (Code Review)]

Lean Sheng Tan has submitted this change. ( https://review.coreboot.org/c/coreboot/+/74762 )

Change subject: acpigen: Add a runtime method to override exposed _Sx sleep states
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acpigen: Add a runtime method to override exposed _Sx sleep states

This allows mainboards to override available sleep states at runtime.
This is done by adding a IntObj in SSDT that DSDT consumes to override
the available _Sx states.

Signed-off-by: Arthur Heymans 
Change-Id: Ic21830c1ef9c183b1e3005cc1f8b7daf7e9ea998
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74762
Reviewed-by: Nico Huber 
Reviewed-by: Jakub Czapiga 
Reviewed-by: Jan Samek 
Tested-by: build bot (Jenkins) 
Reviewed-by: Lean Sheng Tan 
---
M src/acpi/acpigen.c
M src/include/acpi/acpigen.h
M src/southbridge/intel/common/acpi/sleepstates.asl
3 files changed, 43 insertions(+), 0 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Nico Huber: Looks good to me, but someone else must approve
  Lean Sheng Tan: Looks good to me, approved
  Jan Samek: Looks good to me, but someone else must approve
  Jakub Czapiga: Looks good to me, but someone else must approve

diff --git a/src/acpi/acpigen.c b/src/acpi/acpigen.c
index d613bec..94a6f90 100644
--- a/src/acpi/acpigen.c
+++ b/src/acpi/acpigen.c
@@ -2364,3 +2364,17 @@
    acpigen_emit_byte(LOCAL7_OP);
    acpigen_pop_len(); /* While */
 }
+
+void acpigen_ssdt_override_sleep_states(bool enable_s1, bool enable_s2, bool enable_s3,
+					bool enable_s4)
+{
+	assert(!(enable_s1 && CONFIG(ACPI_S1_NOT_SUPPORTED)));
+	assert(!(enable_s3 && !CONFIG(HAVE_ACPI_RESUME)));
+	assert(!(enable_s4 && CONFIG(DISABLE_ACPI_HIBERNATE)));
+
+	acpigen_write_scope("\");
+	uint32_t sleep_enable = (enable_s1 << 0) | (enable_s2 << 1)
+		| (enable_s3 << 2) | (enable_s4 << 3);
+	acpigen_write_name_dword("OSFG", sleep_enable);
+	acpigen_pop_len();
+}
diff --git a/src/include/acpi/acpigen.h b/src/include/acpi/acpigen.h
index 180e937..fc1d01b 100644
--- a/src/include/acpi/acpigen.h
+++ b/src/include/acpi/acpigen.h
@@ -695,4 +695,8 @@
 /* Emits Notify(namestr, value) */
 void acpigen_notify(const char *namestr, int value);

+/* Create a namespace \OSFG to override the enabled sleep states */
+void acpigen_ssdt_override_sleep_states(bool enable_s1, bool enable_s2, bool enable_s3,
+					bool enable_s4);
+
 #endif /* __ACPI_ACPIGEN_H__ */
diff --git a/src/southbridge/intel/common/acpi/sleepstates.asl b/src/southbridge/intel/common/acpi/sleepstates.asl
index 079ab1a..14ed86e 100644
--- a/src/southbridge/intel/common/acpi/sleepstates.asl
+++ b/src/southbridge/intel/common/acpi/sleepstates.asl
@@ -15,6 +15,11 @@
    SSFG &= 0xf7
 }

+External (\OSFG, IntObj)
+If (CondRefOf(\OSFG)) {
+	SSFG = \OSFG
+}
+
 /* Supported sleep states: */
 Name(_S0, Package () {0x00, 0x00, 0x00, 0x00} )	/* (S0) - working state */