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authorPierre Gondois <pierre.gondois@arm.com>2022-05-18 11:08:57 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2022-05-19 19:45:34 +0200
commit0651ab90e4ade17f1d4f4367b70f6120480410f3 (patch)
tree5876bb3f8913c34b617e391d7fa36d59a8a02ed7 /drivers/acpi
parent514ff1bcd98d7f57361025e2200b803d3ddde6c8 (diff)
ACPI: CPPC: Check _OSC for flexible address space
ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities': Starting with ACPI Specification 6.2, all _CPC registers can be in PCC, System Memory, System IO, or Functional Fixed Hardware address spaces. OSPM support for this more flexible register space scheme is indicated by the “Flexible Address Space for CPPC Registers” _OSC bit Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in: - PCC or Functional Fixed Hardware address space if defined - SystemMemory address space (NULL register) if not defined Add the corresponding _OSC bit and check it when parsing _CPC objects. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/bus.c18
-rw-r--r--drivers/acpi/cppc_acpi.c9
2 files changed, 27 insertions, 0 deletions
diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
index 3e58b613a2c4..9eca43d1d941 100644
--- a/drivers/acpi/bus.c
+++ b/drivers/acpi/bus.c
@@ -279,6 +279,20 @@ bool osc_pc_lpi_support_confirmed;
EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
/*
+ * ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
+ * Starting with ACPI Specification 6.2, all _CPC registers can be in
+ * PCC, System Memory, System IO, or Functional Fixed Hardware address
+ * spaces. OSPM support for this more flexible register space scheme is
+ * indicated by the “Flexible Address Space for CPPC Registers” _OSC bit.
+ *
+ * Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
+ * - PCC or Functional Fixed Hardware address space if defined
+ * - SystemMemory address space (NULL register) if not defined
+ */
+bool osc_cpc_flexible_adr_space_confirmed;
+EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
+
+/*
* ACPI 6.4 Operating System Capabilities for USB.
*/
bool osc_sb_native_usb4_support_confirmed;
@@ -321,6 +335,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
}
#endif
+ capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
+
if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
@@ -366,6 +382,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
osc_sb_native_usb4_support_confirmed =
capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
+ osc_cpc_flexible_adr_space_confirmed =
+ capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
}
kfree(context.ret.pointer);
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index bc1454789a06..6f09fe011544 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -736,6 +736,11 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
if (gas_t->address) {
void __iomem *addr;
+ if (!osc_cpc_flexible_adr_space_confirmed) {
+ pr_debug("Flexible address space capability not supported\n");
+ goto out_free;
+ }
+
addr = ioremap(gas_t->address, gas_t->bit_width/8);
if (!addr)
goto out_free;
@@ -758,6 +763,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
gas_t->address);
goto out_free;
}
+ if (!osc_cpc_flexible_adr_space_confirmed) {
+ pr_debug("Flexible address space capability not supported\n");
+ goto out_free;
+ }
} else {
if (gas_t->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE || !cpc_ffh_supported()) {
/* Support only PCC, SystemMemory, SystemIO, and FFH type regs. */