platform/x86/amd: pmf: Add infrastructure for quirking supported funcs

In the event of a BIOS bug add infrastructure that will be utilized
to override the return value for supported_funcs to avoid enabling
features.

Signed-off-by: Mario Limonciello <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Ilpo Järvinen <[email protected]>
Signed-off-by: Ilpo Järvinen <[email protected]>

Author: superm1

drivers/platform/x86/amd/pmf/Makefile

@@ -7,4 +7,4 @@
 obj-$(CONFIG_AMD_PMF) += amd-pmf.o
 amd-pmf-objs := core.o acpi.o sps.o \
 		auto-mode.o cnqf.o \
-		tee-if.o spc.o
+		tee-if.o spc.o pmf-quirks.o

drivers/platform/x86/amd/pmf/acpi.c

@@ -343,7 +343,10 @@ static int apmf_if_verify_interface(struct amd_pmf_dev *pdev)
 	if (err)
 		return err;
 
-	pdev->supported_func = output.supported_functions;
+	/* only set if not already set by a quirk */
+	if (!pdev->supported_func)
+		pdev->supported_func = output.supported_functions;
+
 	dev_dbg(pdev->dev, "supported functions:0x%x notifications:0x%x version:%u\n",
 		output.supported_functions, output.notification_mask, output.version);
 

drivers/platform/x86/amd/pmf/core.c

@@ -445,6 +445,7 @@ static int amd_pmf_probe(struct platform_device *pdev)
 	mutex_init(&dev->lock);
 	mutex_init(&dev->update_mutex);
 
+	amd_pmf_quirks_init(dev);
 	apmf_acpi_init(dev);
 	platform_set_drvdata(pdev, dev);
 	amd_pmf_dbgfs_register(dev);

drivers/platform/x86/amd/pmf/pmf-quirks.c

@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AMD Platform Management Framework Driver Quirks
+ *
+ * Copyright (c) 2024, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: Mario Limonciello <[email protected]>
+ */
+
+#include <linux/dmi.h>
+
+#include "pmf.h"
+
+struct quirk_entry {
+	u32 supported_func;
+};
+
+static struct quirk_entry quirk_no_sps_bug = {
+	.supported_func = 0x4003,
+};
+
+static const struct dmi_system_id fwbug_list[] = {
+	{}
+};
+
+void amd_pmf_quirks_init(struct amd_pmf_dev *dev)
+{
+	const struct dmi_system_id *dmi_id;
+	struct quirk_entry *quirks;
+
+	dmi_id = dmi_first_match(fwbug_list);
+	if (!dmi_id)
+		return;
+
+	quirks = dmi_id->driver_data;
+	if (quirks->supported_func) {
+		dev->supported_func = quirks->supported_func;
+		pr_info("Using supported funcs quirk to avoid %s platform firmware bug\n",
+			dmi_id->ident);
+	}
+}
+

drivers/platform/x86/amd/pmf/pmf.h

@@ -720,4 +720,7 @@ int apmf_check_smart_pc(struct amd_pmf_dev *pmf_dev);
 void amd_pmf_populate_ta_inputs(struct amd_pmf_dev *dev, struct ta_pmf_enact_table *in);
 void amd_pmf_dump_ta_inputs(struct amd_pmf_dev *dev, struct ta_pmf_enact_table *in);
 
+/* Quirk infrastructure */
+void amd_pmf_quirks_init(struct amd_pmf_dev *dev);
+
 #endif /* PMF_H */