From: Akshu Agrawal <Akshu.Agrawal@amd.com>
Date: Thu, 18 Jan 2018 15:51:30 +0530
Subject: cpufreq: AMD: Ignore the check for ProcFeedback in ST/CZ
Git-commit: 59a3b3a8db16621574cbac69f6f1eddb9c60e821
Patch-mainline: v4.16-rc1
References: fate#327735

In ST/CZ CPUID 8000_0007_EDX[11, ProcFeedbackInterface] is 0,
but the mechanism is still available and can be used.

Signed-off-by: Akshu Agrawal <akshu.agrawal@amd.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
---
 drivers/cpufreq/amd_freq_sensitivity.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/amd_freq_sensitivity.c b/drivers/cpufreq/amd_freq_sensitivity.c
index 042023bbbf62..be926d9a66e5 100644
--- a/drivers/cpufreq/amd_freq_sensitivity.c
+++ b/drivers/cpufreq/amd_freq_sensitivity.c
@@ -14,6 +14,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/types.h>
+#include <linux/pci.h>
 #include <linux/percpu-defs.h>
 #include <linux/init.h>
 #include <linux/mod_devicetable.h>
@@ -109,12 +110,18 @@ static unsigned int amd_powersave_bias_target(struct cpufreq_policy *policy,
 static int __init amd_freq_sensitivity_init(void)
 {
 	u64 val;
+	struct pci_dev *pcidev;
 
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
 		return -ENODEV;
 
-	if (!static_cpu_has(X86_FEATURE_PROC_FEEDBACK))
-		return -ENODEV;
+	pcidev = pci_get_device(PCI_VENDOR_ID_AMD,
+			PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, NULL);
+
+	if (!pcidev) {
+		if (!static_cpu_has(X86_FEATURE_PROC_FEEDBACK))
+			return -ENODEV;
+	}
 
 	if (rdmsrl_safe(MSR_AMD64_FREQ_SENSITIVITY_ACTUAL, &val))
 		return -ENODEV;