Commit 113c6097 authored by Fenghua Yu's avatar Fenghua Yu Committed by Thomas Gleixner

x86/intel_rdt: Add Haswell feature discovery

Some Haswell generation CPUs support RDT, but they don't enumerate this via
CPUID.  Use rdmsr_safe() and wrmsr_safe() to probe the MSRs on cpu model 63
(INTEL_FAM6_HASWELL_X)

Move the relevant defines into a common header file which is shared between
RDT/CQM and RDT/Allocation to avoid duplication.
Signed-off-by: default avatarFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-8-git-send-email-fenghua.yu@intel.comSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 78e99b4a
...@@ -7,9 +7,9 @@ ...@@ -7,9 +7,9 @@
#include <linux/perf_event.h> #include <linux/perf_event.h>
#include <linux/slab.h> #include <linux/slab.h>
#include <asm/cpu_device_id.h> #include <asm/cpu_device_id.h>
#include <asm/intel_rdt_common.h>
#include "../perf_event.h" #include "../perf_event.h"
#define MSR_IA32_PQR_ASSOC 0x0c8f
#define MSR_IA32_QM_CTR 0x0c8e #define MSR_IA32_QM_CTR 0x0c8e
#define MSR_IA32_QM_EVTSEL 0x0c8d #define MSR_IA32_QM_EVTSEL 0x0c8d
......
#ifndef _ASM_X86_INTEL_RDT_H
#define _ASM_X86_INTEL_RDT_H
#define IA32_L3_CBM_BASE 0xc90
#endif /* _ASM_X86_INTEL_RDT_H */
#ifndef _ASM_X86_INTEL_RDT_COMMON_H
#define _ASM_X86_INTEL_RDT_COMMON_H
#define MSR_IA32_PQR_ASSOC 0x0c8f
#endif /* _ASM_X86_INTEL_RDT_COMMON_H */
...@@ -27,16 +27,57 @@ ...@@ -27,16 +27,57 @@
#include <linux/slab.h> #include <linux/slab.h>
#include <linux/err.h> #include <linux/err.h>
#include <asm/intel_rdt_common.h>
#include <asm/intel-family.h>
#include <asm/intel_rdt.h>
/*
* cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs
* as they do not have CPUID enumeration support for Cache allocation.
* The check for Vendor/Family/Model is not enough to guarantee that
* the MSRs won't #GP fault because only the following SKUs support
* CAT:
* Intel(R) Xeon(R) CPU E5-2658 v3 @ 2.20GHz
* Intel(R) Xeon(R) CPU E5-2648L v3 @ 1.80GHz
* Intel(R) Xeon(R) CPU E5-2628L v3 @ 2.00GHz
* Intel(R) Xeon(R) CPU E5-2618L v3 @ 2.30GHz
* Intel(R) Xeon(R) CPU E5-2608L v3 @ 2.00GHz
* Intel(R) Xeon(R) CPU E5-2658A v3 @ 2.20GHz
*
* Probe by trying to write the first of the L3 cach mask registers
* and checking that the bits stick. Max CLOSids is always 4 and max cbm length
* is always 20 on hsw server parts. The minimum cache bitmask length
* allowed for HSW server is always 2 bits. Hardcode all of them.
*/
static inline bool cache_alloc_hsw_probe(void)
{
if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
boot_cpu_data.x86 == 6 &&
boot_cpu_data.x86_model == INTEL_FAM6_HASWELL_X) {
u32 l, h, max_cbm = BIT_MASK(20) - 1;
if (wrmsr_safe(IA32_L3_CBM_BASE, max_cbm, 0))
return false;
rdmsr(IA32_L3_CBM_BASE, l, h);
/* If all the bits were set in MSR, return success */
return l == max_cbm;
}
return false;
}
static inline bool get_rdt_resources(void) static inline bool get_rdt_resources(void)
{ {
bool ret = false; if (cache_alloc_hsw_probe())
return true;
if (!boot_cpu_has(X86_FEATURE_RDT_A)) if (!boot_cpu_has(X86_FEATURE_RDT_A))
return false; return false;
if (boot_cpu_has(X86_FEATURE_CAT_L3)) if (!boot_cpu_has(X86_FEATURE_CAT_L3))
ret = true; return false;
return ret; return true;
} }
static int __init intel_rdt_late_init(void) static int __init intel_rdt_late_init(void)
......
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