linux/arch/x86/kernel/cpu/zhaoxin.c
Tony W Wang-oc 283bab9809 x86/cpu: Remove redundant cpu_detect_cache_sizes() call
Both functions call init_intel_cacheinfo() which computes L2 and L3 cache
sizes from CPUID(4). But then they also call cpu_detect_cache_sizes() a
bit later which computes ->x86_tlbsize and L2 size from CPUID(80000006).

However, the latter call is not needed because

 - on these CPUs, CPUID(80000006).EBX for ->x86_tlbsize is reserved

 - CPUID(80000006).ECX for the L2 size has the same result as CPUID(4)

Therefore, remove the latter call to simplify the code.

 [ bp: Rewrite commit message. ]

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1579075257-6985-1-git-send-email-TonyWWang-oc@zhaoxin.com
2020-01-20 16:32:35 +01:00

133 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/sched.h>
#include <linux/sched/clock.h>
#include <asm/cpufeature.h>
#include "cpu.h"
#define MSR_ZHAOXIN_FCR57 0x00001257
#define ACE_PRESENT (1 << 6)
#define ACE_ENABLED (1 << 7)
#define ACE_FCR (1 << 7) /* MSR_ZHAOXIN_FCR */
#define RNG_PRESENT (1 << 2)
#define RNG_ENABLED (1 << 3)
#define RNG_ENABLE (1 << 8) /* MSR_ZHAOXIN_RNG */
static void init_zhaoxin_cap(struct cpuinfo_x86 *c)
{
u32 lo, hi;
/* Test for Extended Feature Flags presence */
if (cpuid_eax(0xC0000000) >= 0xC0000001) {
u32 tmp = cpuid_edx(0xC0000001);
/* Enable ACE unit, if present and disabled */
if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
rdmsr(MSR_ZHAOXIN_FCR57, lo, hi);
/* Enable ACE unit */
lo |= ACE_FCR;
wrmsr(MSR_ZHAOXIN_FCR57, lo, hi);
pr_info("CPU: Enabled ACE h/w crypto\n");
}
/* Enable RNG unit, if present and disabled */
if ((tmp & (RNG_PRESENT | RNG_ENABLED)) == RNG_PRESENT) {
rdmsr(MSR_ZHAOXIN_FCR57, lo, hi);
/* Enable RNG unit */
lo |= RNG_ENABLE;
wrmsr(MSR_ZHAOXIN_FCR57, lo, hi);
pr_info("CPU: Enabled h/w RNG\n");
}
/*
* Store Extended Feature Flags as word 5 of the CPU
* capability bit array
*/
c->x86_capability[CPUID_C000_0001_EDX] = cpuid_edx(0xC0000001);
}
if (c->x86 >= 0x6)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
}
static void early_init_zhaoxin(struct cpuinfo_x86 *c)
{
if (c->x86 >= 0x6)
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_SYSENTER32);
#endif
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
}
if (c->cpuid_level >= 0x00000001) {
u32 eax, ebx, ecx, edx;
cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
/*
* If HTT (EDX[28]) is set EBX[16:23] contain the number of
* apicids which are reserved per package. Store the resulting
* shift value for the package management code.
*/
if (edx & (1U << 28))
c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
}
}
static void init_zhaoxin(struct cpuinfo_x86 *c)
{
early_init_zhaoxin(c);
init_intel_cacheinfo(c);
detect_num_cpu_cores(c);
#ifdef CONFIG_X86_32
detect_ht(c);
#endif
if (c->cpuid_level > 9) {
unsigned int eax = cpuid_eax(10);
/*
* Check for version and the number of counters
* Version(eax[7:0]) can't be 0;
* Counters(eax[15:8]) should be greater than 1;
*/
if ((eax & 0xff) && (((eax >> 8) & 0xff) > 1))
set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
}
if (c->x86 >= 0x6)
init_zhaoxin_cap(c);
#ifdef CONFIG_X86_64
set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
#endif
init_ia32_feat_ctl(c);
}
#ifdef CONFIG_X86_32
static unsigned int
zhaoxin_size_cache(struct cpuinfo_x86 *c, unsigned int size)
{
return size;
}
#endif
static const struct cpu_dev zhaoxin_cpu_dev = {
.c_vendor = "zhaoxin",
.c_ident = { " Shanghai " },
.c_early_init = early_init_zhaoxin,
.c_init = init_zhaoxin,
#ifdef CONFIG_X86_32
.legacy_cache_size = zhaoxin_size_cache,
#endif
.c_x86_vendor = X86_VENDOR_ZHAOXIN,
};
cpu_dev_register(zhaoxin_cpu_dev);