From a4c447533a18ee86e07232d6344ba12b1f9c5077 Mon Sep 17 00:00:00 2001
From: Len Brown <len.brown@intel.com>
Date: Thu, 9 Nov 2017 02:19:39 -0500
Subject: [PATCH] intel_idle: Graceful probe failure when MWAIT is disabled
Git-commit: a4c447533a18ee86e07232d6344ba12b1f9c5077
Patch-mainline: v4.15-rc1
References: bsc#1174115
When MWAIT is disabled, intel_idle refuses to probe.
But it may mis-lead the user by blaming this on the model number:
Intel_idle: does not run on family 6 modesl 79
So defer the check for MWAIT until after the model# white-list check succeeds,
and if the MWAIT check fails, tell the user how to fix it:
Intel_idle: Please enable MWAIT in BIOS SETUP
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/idle/intel_idle.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 5db5e3176f6a..9c93abdf635f 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -1066,7 +1066,7 @@ static const struct idle_cpu idle_cpu_dnv = {
};
#define ICPU(model, cpu) \
- { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu }
+ { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, (unsigned long)&cpu }
static const struct x86_cpu_id intel_idle_ids[] __initconst = {
ICPU(INTEL_FAM6_NEHALEM_EP, idle_cpu_nehalem),
@@ -1130,6 +1130,11 @@ static int __init intel_idle_probe(void)
return -ENODEV;
}
+ if (!boot_cpu_has(X86_FEATURE_MWAIT)) {
+ pr_debug("Please enable MWAIT in BIOS SETUP\n");
+ return -ENODEV;
+ }
+
if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
return -ENODEV;
--
2.16.4