drivers/acpi/bus.c | 85 +++++++++++++++++++++++++---------------------------- 1 file changed, 41 insertions(+), 44 deletions(-)
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The feature mask creation for \_SB._OSC is messy and hard to follow,
so clean it up and make all of the CPPC-related features depend on
CONFIG_ACPI_CPPC_LIB as they will not work if it is not set anyway.
Also make acpi_bus_osc_negotiate_platform_control() print a message
including a bit mask representig the features for which control has
been granted.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
---
v1 -> v2.1:
* Print one more message including the initial feature mask before processing.
* Add R-by from Jonathan (assuming it still applies).
---
drivers/acpi/bus.c | 85 +++++++++++++++++++++++++----------------------------
1 file changed, 41 insertions(+), 44 deletions(-)
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -445,73 +445,70 @@ bool osc_sb_cppc2_support_acked;
static void acpi_bus_osc_negotiate_platform_control(void)
{
static const u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
- u32 capbuf[2];
+ u32 capbuf[2], feature_mask;
struct acpi_buffer cap = {
.pointer = capbuf,
.length = sizeof(capbuf),
};
acpi_handle handle;
- capbuf[OSC_SUPPORT_DWORD] = OSC_SB_PR3_SUPPORT; /* _PR3 is in use */
+ feature_mask = OSC_SB_PR3_SUPPORT | OSC_SB_HOTPLUG_OST_SUPPORT |
+ OSC_SB_PCLPI_SUPPORT | OSC_SB_OVER_16_PSTATES_SUPPORT |
+ OSC_SB_GED_SUPPORT | OSC_SB_IRQ_RESOURCE_SOURCE_SUPPORT;
+
+ if (IS_ENABLED(CONFIG_ARM64) || IS_ENABLED(CONFIG_X86))
+ feature_mask |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
+
+ if (IS_ENABLED(CONFIG_ACPI_CPPC_LIB)) {
+ feature_mask |= OSC_SB_CPC_SUPPORT | OSC_SB_CPCV2_SUPPORT |
+ OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+ if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
+ feature_mask |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
+ }
+
if (IS_ENABLED(CONFIG_ACPI_PROCESSOR_AGGREGATOR))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PAD_SUPPORT;
+ feature_mask |= OSC_SB_PAD_SUPPORT;
+
if (IS_ENABLED(CONFIG_ACPI_PROCESSOR))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PPC_OST_SUPPORT;
+ feature_mask |= OSC_SB_PPC_OST_SUPPORT;
+
if (IS_ENABLED(CONFIG_ACPI_THERMAL))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_FAST_THERMAL_SAMPLING_SUPPORT;
+ feature_mask |= OSC_SB_FAST_THERMAL_SAMPLING_SUPPORT;
+
if (IS_ENABLED(CONFIG_ACPI_BATTERY))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_BATTERY_CHARGE_LIMITING_SUPPORT;
+ feature_mask |= OSC_SB_BATTERY_CHARGE_LIMITING_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_HOTPLUG_OST_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PCLPI_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_OVER_16_PSTATES_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GED_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_IRQ_RESOURCE_SOURCE_SUPPORT;
if (IS_ENABLED(CONFIG_ACPI_PRMT))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_PRM_SUPPORT;
- if (IS_ENABLED(CONFIG_ACPI_FFH))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_FFH_OPR_SUPPORT;
-
-#ifdef CONFIG_ARM64
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
-#endif
-#ifdef CONFIG_X86
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_GENERIC_INITIATOR_SUPPORT;
-#endif
-
-#ifdef CONFIG_ACPI_CPPC_LIB
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_SUPPORT;
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPCV2_SUPPORT;
-#endif
-
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+ feature_mask |= OSC_SB_PRM_SUPPORT;
- if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
+ if (IS_ENABLED(CONFIG_ACPI_FFH))
+ feature_mask |= OSC_SB_FFH_OPR_SUPPORT;
if (IS_ENABLED(CONFIG_USB4))
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_NATIVE_USB4_SUPPORT;
+ feature_mask |= OSC_SB_NATIVE_USB4_SUPPORT;
if (!ghes_disable)
- capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_APEI_SUPPORT;
+ feature_mask |= OSC_SB_APEI_SUPPORT;
+
if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
return;
+ capbuf[OSC_SUPPORT_DWORD] = feature_mask;
+
+ acpi_handle_info(handle, "platform _OSC: OS support mask [%08x]\n", feature_mask);
+
if (acpi_osc_handshake(handle, sb_uuid_str, 1, &cap))
return;
-#ifdef CONFIG_ACPI_CPPC_LIB
- osc_sb_cppc2_support_acked = capbuf[OSC_SUPPORT_DWORD] & OSC_SB_CPCV2_SUPPORT;
-#endif
-
- osc_sb_apei_support_acked =
- capbuf[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
- osc_pc_lpi_support_confirmed =
- capbuf[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
- osc_sb_native_usb4_support_confirmed =
- capbuf[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
- osc_cpc_flexible_adr_space_confirmed =
- capbuf[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+ feature_mask = capbuf[OSC_SUPPORT_DWORD];
+
+ acpi_handle_info(handle, "platform _OSC: OS control mask [%08x]\n", feature_mask);
+
+ osc_sb_cppc2_support_acked = feature_mask & OSC_SB_CPCV2_SUPPORT;
+ osc_sb_apei_support_acked = feature_mask & OSC_SB_APEI_SUPPORT;
+ osc_pc_lpi_support_confirmed = feature_mask & OSC_SB_PCLPI_SUPPORT;
+ osc_sb_native_usb4_support_confirmed = feature_mask & OSC_SB_NATIVE_USB4_SUPPORT;
+ osc_cpc_flexible_adr_space_confirmed = feature_mask & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
}
/*On Mon, 22 Dec 2025 20:23:29 +0100 "Rafael J. Wysocki" <rafael@kernel.org> wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > The feature mask creation for \_SB._OSC is messy and hard to follow, > so clean it up and make all of the CPPC-related features depend on > CONFIG_ACPI_CPPC_LIB as they will not work if it is not set anyway. > > Also make acpi_bus_osc_negotiate_platform_control() print a message > including a bit mask representig the features for which control has > been granted. > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com> > --- > > v1 -> v2.1: > * Print one more message including the initial feature mask before processing. > * Add R-by from Jonathan (assuming it still applies). FWIW the extra message makes sense to me. So RB definitely still applies.
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