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Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r--arch/x86/kernel/cpu/amd.c309
1 files changed, 209 insertions, 100 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index f4773f4aae3..ce8b8ff0e0e 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -1,23 +1,55 @@
#include <linux/export.h>
-#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/elf.h>
#include <linux/mm.h>
#include <linux/io.h>
+#include <linux/sched.h>
#include <asm/processor.h>
#include <asm/apic.h>
#include <asm/cpu.h>
#include <asm/pci-direct.h>
#ifdef CONFIG_X86_64
-# include <asm/numa_64.h>
# include <asm/mmconfig.h>
# include <asm/cacheflush.h>
#endif
#include "cpu.h"
+static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
+{
+ u32 gprs[8] = { 0 };
+ int err;
+
+ WARN_ONCE((boot_cpu_data.x86 != 0xf),
+ "%s should only be used on K8!\n", __func__);
+
+ gprs[1] = msr;
+ gprs[7] = 0x9c5a203a;
+
+ err = rdmsr_safe_regs(gprs);
+
+ *p = gprs[0] | ((u64)gprs[2] << 32);
+
+ return err;
+}
+
+static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
+{
+ u32 gprs[8] = { 0 };
+
+ WARN_ONCE((boot_cpu_data.x86 != 0xf),
+ "%s should only be used on K8!\n", __func__);
+
+ gprs[0] = (u32)val;
+ gprs[1] = msr;
+ gprs[2] = val >> 32;
+ gprs[7] = 0x9c5a203a;
+
+ return wrmsr_safe_regs(gprs);
+}
+
#ifdef CONFIG_X86_32
/*
* B step AMD K6 before B 9730xxxx have hardware bugs that can cause
@@ -25,17 +57,18 @@
* contact AMD for precise details and a CPU swap.
*
* See http://www.multimania.com/poulot/k6bug.html
- * http://www.amd.com/K6/k6docs/revgd.html
+ * and section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
+ * (Publication # 21266 Issue Date: August 1998)
*
* The following test is erm.. interesting. AMD neglected to up
* the chip setting when fixing the bug but they also tweaked some
* performance at the same time..
*/
-extern void vide(void);
-__asm__(".align 4\nvide: ret");
+extern __visible void vide(void);
+__asm__(".globl vide\n\t.align 4\nvide: ret");
-static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
+static void init_amd_k5(struct cpuinfo_x86 *c)
{
/*
* General Systems BIOSen alias the cpu frequency registers
@@ -53,10 +86,10 @@ static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
}
-static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
+static void init_amd_k6(struct cpuinfo_x86 *c)
{
u32 l, h;
- int mbytes = num_physpages >> (20-PAGE_SHIFT);
+ int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
if (c->x86_model < 6) {
/* Based on AMD doc 20734R - June 2000 */
@@ -93,7 +126,6 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
"system stability may be impaired when more than 32 MB are used.\n");
else
printk(KERN_CONT "probably OK (after B9730xxxx).\n");
- printk(KERN_INFO "Please see http://membres.lycos.fr/poulot/k6bug.html\n");
}
/* K6 with old style WHCR */
@@ -146,7 +178,7 @@ static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
}
}
-static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
+static void amd_k7_smp_check(struct cpuinfo_x86 *c)
{
/* calling is from identify_secondary_cpu() ? */
if (!c->cpu_index)
@@ -159,11 +191,11 @@ static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
/* Athlon 660/661 is valid. */
if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
(c->x86_mask == 1)))
- goto valid_k7;
+ return;
/* Duron 670 is valid */
if ((c->x86_model == 7) && (c->x86_mask == 0))
- goto valid_k7;
+ return;
/*
* Athlon 662, Duron 671, and Athlon >model 7 have capability
@@ -176,7 +208,7 @@ static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
((c->x86_model == 7) && (c->x86_mask >= 1)) ||
(c->x86_model > 7))
if (cpu_has_mp)
- goto valid_k7;
+ return;
/* If we get here, not a certified SMP capable AMD system. */
@@ -186,14 +218,10 @@ static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
*/
WARN_ONCE(1, "WARNING: This combination of AMD"
" processors is not suitable for SMP.\n");
- if (!test_taint(TAINT_UNSAFE_SMP))
- add_taint(TAINT_UNSAFE_SMP);
-
-valid_k7:
- ;
+ add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
}
-static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
+static void init_amd_k7(struct cpuinfo_x86 *c)
{
u32 l, h;
@@ -205,9 +233,7 @@ static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
if (c->x86_model >= 6 && c->x86_model <= 10) {
if (!cpu_has(c, X86_FEATURE_XMM)) {
printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
- rdmsr(MSR_K7_HWCR, l, h);
- l &= ~0x00008000;
- wrmsr(MSR_K7_HWCR, l, h);
+ msr_clear_bit(MSR_K7_HWCR, 15);
set_cpu_cap(c, X86_FEATURE_XMM);
}
}
@@ -238,7 +264,7 @@ static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
* To workaround broken NUMA config. Read the comment in
* srat_detect_node().
*/
-static int __cpuinit nearby_node(int apicid)
+static int nearby_node(int apicid)
{
int i, node;
@@ -263,14 +289,14 @@ static int __cpuinit nearby_node(int apicid)
* (2) AMD processors supporting compute units
*/
#ifdef CONFIG_X86_HT
-static void __cpuinit amd_get_topology(struct cpuinfo_x86 *c)
+static void amd_get_topology(struct cpuinfo_x86 *c)
{
u32 nodes, cores_per_cu = 1;
u8 node_id;
int cpu = smp_processor_id();
/* get information required for multi-node processors */
- if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
+ if (cpu_has_topoext) {
u32 eax, ebx, ecx, edx;
cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
@@ -310,10 +336,10 @@ static void __cpuinit amd_get_topology(struct cpuinfo_x86 *c)
#endif
/*
- * On a AMD dual core setup the lower bits of the APIC id distingush the cores.
+ * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
* Assumes number of cores is a power of two.
*/
-static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
+static void amd_detect_cmp(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_HT
unsigned bits;
@@ -330,9 +356,9 @@ static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
#endif
}
-int amd_get_nb_id(int cpu)
+u16 amd_get_nb_id(int cpu)
{
- int id = 0;
+ u16 id = 0;
#ifdef CONFIG_SMP
id = per_cpu(cpu_llc_id, cpu);
#endif
@@ -340,7 +366,7 @@ int amd_get_nb_id(int cpu)
}
EXPORT_SYMBOL_GPL(amd_get_nb_id);
-static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
+static void srat_detect_node(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_NUMA
int cpu = smp_processor_id();
@@ -352,10 +378,11 @@ static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
node = per_cpu(cpu_llc_id, cpu);
/*
- * If core numbers are inconsistent, it's likely a multi-fabric platform,
- * so invoke platform-specific handler
+ * On multi-fabric platform (e.g. Numascale NumaChip) a
+ * platform-specific handler needs to be called to fixup some
+ * IDs of the CPU.
*/
- if (c->phys_proc_id != node)
+ if (x86_cpuinit.fixup_cpu_id)
x86_cpuinit.fixup_cpu_id(c, node);
if (!node_online(node)) {
@@ -391,7 +418,7 @@ static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
#endif
}
-static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
+static void early_init_amd_mc(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_HT
unsigned bits, ecx;
@@ -417,7 +444,7 @@ static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
#endif
}
-static void __cpuinit bsp_init_amd(struct cpuinfo_x86 *c)
+static void bsp_init_amd(struct cpuinfo_x86 *c)
{
if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
@@ -445,7 +472,7 @@ static void __cpuinit bsp_init_amd(struct cpuinfo_x86 *c)
}
}
-static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
+static void early_init_amd(struct cpuinfo_x86 *c)
{
early_init_amd_mc(c);
@@ -456,6 +483,8 @@ static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
if (c->x86_power & (1 << 8)) {
set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
+ if (!check_tsc_unstable())
+ set_sched_clock_stable();
}
#ifdef CONFIG_X86_64
@@ -476,15 +505,22 @@ static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
}
#endif
+
+ /* F16h erratum 793, CVE-2013-6885 */
+ if (c->x86 == 0x16 && c->x86_model <= 0xf)
+ msr_set_bit(MSR_AMD64_LS_CFG, 15);
}
-static void __cpuinit init_amd(struct cpuinfo_x86 *c)
+static const int amd_erratum_383[];
+static const int amd_erratum_400[];
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
+
+static void init_amd(struct cpuinfo_x86 *c)
{
u32 dummy;
-
-#ifdef CONFIG_SMP
unsigned long long value;
+#ifdef CONFIG_SMP
/*
* Disable TLB flush filter by setting HWCR.FFDIS on K8
* bit 6 of msr C001_0015
@@ -492,11 +528,8 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
* Errata 63 for SH-B3 steppings
* Errata 122 for all steppings (F+ have it disabled by default)
*/
- if (c->x86 == 0xf) {
- rdmsrl(MSR_K7_HWCR, value);
- value |= 1 << 6;
- wrmsrl(MSR_K7_HWCR, value);
- }
+ if (c->x86 == 0xf)
+ msr_set_bit(MSR_K7_HWCR, 6);
#endif
early_init_amd(c);
@@ -522,12 +555,10 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
* (AMD Erratum #110, docId: 25759).
*/
if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
- u64 val;
-
clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
- if (!rdmsrl_amd_safe(0xc001100d, &val)) {
- val &= ~(1ULL << 32);
- wrmsrl_amd_safe(0xc001100d, val);
+ if (!rdmsrl_amd_safe(0xc001100d, &value)) {
+ value &= ~(1ULL << 32);
+ wrmsrl_amd_safe(0xc001100d, value);
}
}
@@ -576,6 +607,33 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
}
}
+ /* re-enable TopologyExtensions if switched off by BIOS */
+ if ((c->x86 == 0x15) &&
+ (c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
+ !cpu_has(c, X86_FEATURE_TOPOEXT)) {
+
+ if (msr_set_bit(0xc0011005, 54) > 0) {
+ rdmsrl(0xc0011005, value);
+ if (value & BIT_64(54)) {
+ set_cpu_cap(c, X86_FEATURE_TOPOEXT);
+ pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
+ }
+ }
+ }
+
+ /*
+ * The way access filter has a performance penalty on some workloads.
+ * Disable it on the affected CPUs.
+ */
+ if ((c->x86 == 0x15) &&
+ (c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
+
+ if (!rdmsrl_safe(0xc0011021, &value) && !(value & 0x1E)) {
+ value |= 0x1E;
+ wrmsrl_safe(0xc0011021, value);
+ }
+ }
+
cpu_detect_cache_sizes(c);
/* Multi core CPU? */
@@ -588,12 +646,7 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
detect_ht(c);
#endif
- if (c->extended_cpuid_level >= 0x80000006) {
- if (cpuid_edx(0x80000006) & 0xf000)
- num_cache_leaves = 4;
- else
- num_cache_leaves = 3;
- }
+ init_amd_cacheinfo(c);
if (c->x86 >= 0xf)
set_cpu_cap(c, X86_FEATURE_K8);
@@ -621,12 +674,10 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
* benefit in doing so.
*/
if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
+ unsigned long pfn = tseg >> PAGE_SHIFT;
+
printk(KERN_DEBUG "tseg: %010llx\n", tseg);
- if ((tseg>>PMD_SHIFT) <
- (max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||
- ((tseg>>PMD_SHIFT) <
- (max_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) &&
- (tseg>>PMD_SHIFT) >= (1ULL<<(32 - PMD_SHIFT))))
+ if (pfn_range_is_mapped(pfn, pfn + 1))
set_memory_4k((unsigned long)__va(tseg), 1);
}
}
@@ -639,34 +690,42 @@ static void __cpuinit init_amd(struct cpuinfo_x86 *c)
if (c->x86 > 0x11)
set_cpu_cap(c, X86_FEATURE_ARAT);
- /*
- * Disable GART TLB Walk Errors on Fam10h. We do this here
- * because this is always needed when GART is enabled, even in a
- * kernel which has no MCE support built in.
- */
if (c->x86 == 0x10) {
/*
- * BIOS should disable GartTlbWlk Errors themself. If
- * it doesn't do it here as suggested by the BKDG.
+ * Disable GART TLB Walk Errors on Fam10h. We do this here
+ * because this is always needed when GART is enabled, even in a
+ * kernel which has no MCE support built in.
+ * BIOS should disable GartTlbWlk Errors already. If
+ * it doesn't, do it here as suggested by the BKDG.
*
* Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
*/
- u64 mask;
- int err;
+ msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
- err = rdmsrl_safe(MSR_AMD64_MCx_MASK(4), &mask);
- if (err == 0) {
- mask |= (1 << 10);
- checking_wrmsrl(MSR_AMD64_MCx_MASK(4), mask);
- }
+ /*
+ * On family 10h BIOS may not have properly enabled WC+ support,
+ * causing it to be converted to CD memtype. This may result in
+ * performance degradation for certain nested-paging guests.
+ * Prevent this conversion by clearing bit 24 in
+ * MSR_AMD64_BU_CFG2.
+ *
+ * NOTE: we want to use the _safe accessors so as not to #GP kvm
+ * guests on older kvm hosts.
+ */
+ msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
+
+ if (cpu_has_amd_erratum(c, amd_erratum_383))
+ set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
}
+ if (cpu_has_amd_erratum(c, amd_erratum_400))
+ set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
+
rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
}
#ifdef CONFIG_X86_32
-static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c,
- unsigned int size)
+static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
{
/* AMD errata T13 (order #21922) */
if ((c->x86 == 6)) {
@@ -682,12 +741,68 @@ static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c,
}
#endif
-static const struct cpu_dev __cpuinitconst amd_cpu_dev = {
+static void cpu_set_tlb_flushall_shift(struct cpuinfo_x86 *c)
+{
+ tlb_flushall_shift = 6;
+}
+
+static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
+{
+ u32 ebx, eax, ecx, edx;
+ u16 mask = 0xfff;
+
+ if (c->x86 < 0xf)
+ return;
+
+ if (c->extended_cpuid_level < 0x80000006)
+ return;
+
+ cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
+
+ tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
+ tlb_lli_4k[ENTRIES] = ebx & mask;
+
+ /*
+ * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
+ * characteristics from the CPUID function 0x80000005 instead.
+ */
+ if (c->x86 == 0xf) {
+ cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
+ mask = 0xff;
+ }
+
+ /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+ if (!((eax >> 16) & mask))
+ tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
+ else
+ tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
+
+ /* a 4M entry uses two 2M entries */
+ tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
+
+ /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
+ if (!(eax & mask)) {
+ /* Erratum 658 */
+ if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
+ tlb_lli_2m[ENTRIES] = 1024;
+ } else {
+ cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
+ tlb_lli_2m[ENTRIES] = eax & 0xff;
+ }
+ } else
+ tlb_lli_2m[ENTRIES] = eax & mask;
+
+ tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
+
+ cpu_set_tlb_flushall_shift(c);
+}
+
+static const struct cpu_dev amd_cpu_dev = {
.c_vendor = "AMD",
.c_ident = { "AuthenticAMD" },
#ifdef CONFIG_X86_32
- .c_models = {
- { .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
+ .legacy_models = {
+ { .family = 4, .model_names =
{
[3] = "486 DX/2",
[7] = "486 DX/2-WB",
@@ -698,9 +813,10 @@ static const struct cpu_dev __cpuinitconst amd_cpu_dev = {
}
},
},
- .c_size_cache = amd_size_cache,
+ .legacy_cache_size = amd_size_cache,
#endif
.c_early_init = early_init_amd,
+ .c_detect_tlb = cpu_detect_tlb_amd,
.c_bsp_init = bsp_init_amd,
.c_init = init_amd,
.c_x86_vendor = X86_VENDOR_AMD,
@@ -715,8 +831,7 @@ cpu_dev_register(amd_cpu_dev);
* AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
* have an OSVW id assigned, which it takes as first argument. Both take a
* variable number of family-specific model-stepping ranges created by
- * AMD_MODEL_RANGE(). Each erratum also has to be declared as extern const
- * int[] in arch/x86/include/asm/processor.h.
+ * AMD_MODEL_RANGE().
*
* Example:
*
@@ -726,32 +841,28 @@ cpu_dev_register(amd_cpu_dev);
* AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
*/
-const int amd_erratum_400[] =
+#define AMD_LEGACY_ERRATUM(...) { -1, __VA_ARGS__, 0 }
+#define AMD_OSVW_ERRATUM(osvw_id, ...) { osvw_id, __VA_ARGS__, 0 }
+#define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
+ ((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
+#define AMD_MODEL_RANGE_FAMILY(range) (((range) >> 24) & 0xff)
+#define AMD_MODEL_RANGE_START(range) (((range) >> 12) & 0xfff)
+#define AMD_MODEL_RANGE_END(range) ((range) & 0xfff)
+
+static const int amd_erratum_400[] =
AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
-EXPORT_SYMBOL_GPL(amd_erratum_400);
-const int amd_erratum_383[] =
+static const int amd_erratum_383[] =
AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
-EXPORT_SYMBOL_GPL(amd_erratum_383);
-bool cpu_has_amd_erratum(const int *erratum)
+
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
{
- struct cpuinfo_x86 *cpu = __this_cpu_ptr(&cpu_info);
int osvw_id = *erratum++;
u32 range;
u32 ms;
- /*
- * If called early enough that current_cpu_data hasn't been initialized
- * yet, fall back to boot_cpu_data.
- */
- if (cpu->x86 == 0)
- cpu = &boot_cpu_data;
-
- if (cpu->x86_vendor != X86_VENDOR_AMD)
- return false;
-
if (osvw_id >= 0 && osvw_id < 65536 &&
cpu_has(cpu, X86_FEATURE_OSVW)) {
u64 osvw_len;
@@ -776,5 +887,3 @@ bool cpu_has_amd_erratum(const int *erratum)
return false;
}
-
-EXPORT_SYMBOL_GPL(cpu_has_amd_erratum);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 01:04:20 +0000