Revert "ACPI: CPPC: Only probe for _CPC if CPPC v2 is acked"

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2164217
Upstream Status: RHEL Only

This reverts commit 19f75aa. The
upstream commit was backported incorrectly and needs to be reapplied.

Signed-off-by: Mark Langsdorf <mlangsdo@redhat.com>

Author: mlangsdorf

drivers/acpi/bus.c

@@ -297,7 +297,7 @@ EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
 bool osc_sb_native_usb4_support_confirmed;
 EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed);
 
-bool osc_sb_cppc2_support_acked;
+bool osc_sb_cppc_not_supported;
 
 static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48";
 static void acpi_bus_osc_negotiate_platform_control(void)
@@ -357,6 +357,12 @@ static void acpi_bus_osc_negotiate_platform_control(void)
 		return;
 	}
 
+#ifdef CONFIG_X86
+	if (boot_cpu_has(X86_FEATURE_HWP))
+		osc_sb_cppc_not_supported = !(capbuf_ret[OSC_SUPPORT_DWORD] &
+				(OSC_SB_CPC_SUPPORT | OSC_SB_CPCV2_SUPPORT));
+#endif
+
 	/*
 	 * Now run _OSC again with query flag clear and with the caps
 	 * supported by both the OS and the platform.
@@ -370,10 +376,6 @@ static void acpi_bus_osc_negotiate_platform_control(void)
 
 	capbuf_ret = context.ret.pointer;
 	if (context.ret.length > OSC_SUPPORT_DWORD) {
-#ifdef CONFIG_X86
-		osc_sb_cppc2_support_acked = capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPCV2_SUPPORT;
-#endif
-
 		osc_sb_apei_support_acked =
 			capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_APEI_SUPPORT;
 		osc_pc_lpi_support_confirmed =

drivers/acpi/cppc_acpi.c

@@ -673,11 +673,8 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 	acpi_status status;
 	int ret = -ENODATA;
 
-	if (!osc_sb_cppc2_support_acked) {
-		pr_debug("CPPC v2 _OSC not acked\n");
-		if (!cpc_supported_by_cpu())
-			return -ENODEV;
-	}
+	if (osc_sb_cppc_not_supported)
+		return -ENODEV;
 
 	/* Parse the ACPI _CPC table for this CPU. */
 	status = acpi_evaluate_object_typed(handle, "_CPC", NULL, &output,

include/linux/acpi.h

@@ -585,7 +585,7 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context);
 extern bool osc_sb_apei_support_acked;
 extern bool osc_pc_lpi_support_confirmed;
 extern bool osc_sb_native_usb4_support_confirmed;
-extern bool osc_sb_cppc2_support_acked;
+extern bool osc_sb_cppc_not_supported;
 extern bool osc_cpc_flexible_adr_space_confirmed;
 
 /* USB4 Capabilities */