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- // SPDX-License-Identifier: GPL-2.0-only
- #include <linux/export.h>
- #include <linux/bitops.h>
- #include <linux/elf.h>
- #include <linux/mm.h>
- #include <linux/io.h>
- #include <linux/sched.h>
- #include <linux/sched/clock.h>
- #include <linux/random.h>
- #include <linux/topology.h>
- #include <asm/processor.h>
- #include <asm/apic.h>
- #include <asm/cacheinfo.h>
- #include <asm/cpu.h>
- #include <asm/spec-ctrl.h>
- #include <asm/smp.h>
- #include <asm/numa.h>
- #include <asm/pci-direct.h>
- #include <asm/delay.h>
- #include <asm/debugreg.h>
- #include <asm/resctrl.h>
- #ifdef CONFIG_X86_64
- # include <asm/mmconfig.h>
- #endif
- #include "cpu.h"
- /*
- * nodes_per_socket: Stores the number of nodes per socket.
- * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
- * Node Identifiers[10:8]
- */
- static u32 nodes_per_socket = 1;
- /*
- * AMD errata checking
- *
- * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
- * 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().
- *
- * Example:
- *
- * const int amd_erratum_319[] =
- * AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
- * AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
- * AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
- */
- #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));
- static const int amd_erratum_383[] =
- AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
- /* #1054: Instructions Retired Performance Counter May Be Inaccurate */
- static const int amd_erratum_1054[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf));
- static const int amd_zenbleed[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf),
- AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf),
- AMD_MODEL_RANGE(0x17, 0x90, 0x0, 0x91, 0xf),
- AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf));
- static const int amd_div0[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x00, 0x0, 0x2f, 0xf),
- AMD_MODEL_RANGE(0x17, 0x50, 0x0, 0x5f, 0xf));
- static const int amd_erratum_1485[] =
- AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf),
- AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf));
- static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
- {
- int osvw_id = *erratum++;
- u32 range;
- u32 ms;
- if (osvw_id >= 0 && osvw_id < 65536 &&
- cpu_has(cpu, X86_FEATURE_OSVW)) {
- u64 osvw_len;
- rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
- if (osvw_id < osvw_len) {
- u64 osvw_bits;
- rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
- osvw_bits);
- return osvw_bits & (1ULL << (osvw_id & 0x3f));
- }
- }
- /* OSVW unavailable or ID unknown, match family-model-stepping range */
- ms = (cpu->x86_model << 4) | cpu->x86_stepping;
- while ((range = *erratum++))
- if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
- (ms >= AMD_MODEL_RANGE_START(range)) &&
- (ms <= AMD_MODEL_RANGE_END(range)))
- return true;
- return false;
- }
- 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);
- }
- /*
- * B step AMD K6 before B 9730xxxx have hardware bugs that can cause
- * misexecution of code under Linux. Owners of such processors should
- * contact AMD for precise details and a CPU swap.
- *
- * See http://www.multimania.com/poulot/k6bug.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..
- */
- #ifdef CONFIG_X86_32
- extern __visible void vide(void);
- __asm__(".text\n"
- ".globl vide\n"
- ".type vide, @function\n"
- ".align 4\n"
- "vide: ret\n");
- #endif
- static void init_amd_k5(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_X86_32
- /*
- * General Systems BIOSen alias the cpu frequency registers
- * of the Elan at 0x000df000. Unfortunately, one of the Linux
- * drivers subsequently pokes it, and changes the CPU speed.
- * Workaround : Remove the unneeded alias.
- */
- #define CBAR (0xfffc) /* Configuration Base Address (32-bit) */
- #define CBAR_ENB (0x80000000)
- #define CBAR_KEY (0X000000CB)
- if (c->x86_model == 9 || c->x86_model == 10) {
- if (inl(CBAR) & CBAR_ENB)
- outl(0 | CBAR_KEY, CBAR);
- }
- #endif
- }
- static void init_amd_k6(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_X86_32
- u32 l, h;
- int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
- if (c->x86_model < 6) {
- /* Based on AMD doc 20734R - June 2000 */
- if (c->x86_model == 0) {
- clear_cpu_cap(c, X86_FEATURE_APIC);
- set_cpu_cap(c, X86_FEATURE_PGE);
- }
- return;
- }
- if (c->x86_model == 6 && c->x86_stepping == 1) {
- const int K6_BUG_LOOP = 1000000;
- int n;
- void (*f_vide)(void);
- u64 d, d2;
- pr_info("AMD K6 stepping B detected - ");
- /*
- * It looks like AMD fixed the 2.6.2 bug and improved indirect
- * calls at the same time.
- */
- n = K6_BUG_LOOP;
- f_vide = vide;
- OPTIMIZER_HIDE_VAR(f_vide);
- d = rdtsc();
- while (n--)
- f_vide();
- d2 = rdtsc();
- d = d2-d;
- if (d > 20*K6_BUG_LOOP)
- pr_cont("system stability may be impaired when more than 32 MB are used.\n");
- else
- pr_cont("probably OK (after B9730xxxx).\n");
- }
- /* K6 with old style WHCR */
- if (c->x86_model < 8 ||
- (c->x86_model == 8 && c->x86_stepping < 8)) {
- /* We can only write allocate on the low 508Mb */
- if (mbytes > 508)
- mbytes = 508;
- rdmsr(MSR_K6_WHCR, l, h);
- if ((l&0x0000FFFF) == 0) {
- unsigned long flags;
- l = (1<<0)|((mbytes/4)<<1);
- local_irq_save(flags);
- wbinvd();
- wrmsr(MSR_K6_WHCR, l, h);
- local_irq_restore(flags);
- pr_info("Enabling old style K6 write allocation for %d Mb\n",
- mbytes);
- }
- return;
- }
- if ((c->x86_model == 8 && c->x86_stepping > 7) ||
- c->x86_model == 9 || c->x86_model == 13) {
- /* The more serious chips .. */
- if (mbytes > 4092)
- mbytes = 4092;
- rdmsr(MSR_K6_WHCR, l, h);
- if ((l&0xFFFF0000) == 0) {
- unsigned long flags;
- l = ((mbytes>>2)<<22)|(1<<16);
- local_irq_save(flags);
- wbinvd();
- wrmsr(MSR_K6_WHCR, l, h);
- local_irq_restore(flags);
- pr_info("Enabling new style K6 write allocation for %d Mb\n",
- mbytes);
- }
- return;
- }
- if (c->x86_model == 10) {
- /* AMD Geode LX is model 10 */
- /* placeholder for any needed mods */
- return;
- }
- #endif
- }
- static void init_amd_k7(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_X86_32
- u32 l, h;
- /*
- * Bit 15 of Athlon specific MSR 15, needs to be 0
- * to enable SSE on Palomino/Morgan/Barton CPU's.
- * If the BIOS didn't enable it already, enable it here.
- */
- if (c->x86_model >= 6 && c->x86_model <= 10) {
- if (!cpu_has(c, X86_FEATURE_XMM)) {
- pr_info("Enabling disabled K7/SSE Support.\n");
- msr_clear_bit(MSR_K7_HWCR, 15);
- set_cpu_cap(c, X86_FEATURE_XMM);
- }
- }
- /*
- * It's been determined by AMD that Athlons since model 8 stepping 1
- * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
- * As per AMD technical note 27212 0.2
- */
- if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
- rdmsr(MSR_K7_CLK_CTL, l, h);
- if ((l & 0xfff00000) != 0x20000000) {
- pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
- l, ((l & 0x000fffff)|0x20000000));
- wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
- }
- }
- /* calling is from identify_secondary_cpu() ? */
- if (!c->cpu_index)
- return;
- /*
- * Certain Athlons might work (for various values of 'work') in SMP
- * but they are not certified as MP capable.
- */
- /* Athlon 660/661 is valid. */
- if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
- (c->x86_stepping == 1)))
- return;
- /* Duron 670 is valid */
- if ((c->x86_model == 7) && (c->x86_stepping == 0))
- return;
- /*
- * Athlon 662, Duron 671, and Athlon >model 7 have capability
- * bit. It's worth noting that the A5 stepping (662) of some
- * Athlon XP's have the MP bit set.
- * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
- * more.
- */
- if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
- ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
- (c->x86_model > 7))
- if (cpu_has(c, X86_FEATURE_MP))
- return;
- /* If we get here, not a certified SMP capable AMD system. */
- /*
- * Don't taint if we are running SMP kernel on a single non-MP
- * approved Athlon
- */
- WARN_ONCE(1, "WARNING: This combination of AMD"
- " processors is not suitable for SMP.\n");
- add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
- #endif
- }
- #ifdef CONFIG_NUMA
- /*
- * To workaround broken NUMA config. Read the comment in
- * srat_detect_node().
- */
- static int nearby_node(int apicid)
- {
- int i, node;
- for (i = apicid - 1; i >= 0; i--) {
- node = __apicid_to_node[i];
- if (node != NUMA_NO_NODE && node_online(node))
- return node;
- }
- for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
- node = __apicid_to_node[i];
- if (node != NUMA_NO_NODE && node_online(node))
- return node;
- }
- return first_node(node_online_map); /* Shouldn't happen */
- }
- #endif
- /*
- * Fix up cpu_core_id for pre-F17h systems to be in the
- * [0 .. cores_per_node - 1] range. Not really needed but
- * kept so as not to break existing setups.
- */
- static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
- {
- u32 cus_per_node;
- if (c->x86 >= 0x17)
- return;
- cus_per_node = c->x86_max_cores / nodes_per_socket;
- c->cpu_core_id %= cus_per_node;
- }
- /*
- * Fixup core topology information for
- * (1) AMD multi-node processors
- * Assumption: Number of cores in each internal node is the same.
- * (2) AMD processors supporting compute units
- */
- static void amd_get_topology(struct cpuinfo_x86 *c)
- {
- int cpu = smp_processor_id();
- /* get information required for multi-node processors */
- if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
- int err;
- u32 eax, ebx, ecx, edx;
- cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
- c->cpu_die_id = ecx & 0xff;
- if (c->x86 == 0x15)
- c->cu_id = ebx & 0xff;
- if (c->x86 >= 0x17) {
- c->cpu_core_id = ebx & 0xff;
- if (smp_num_siblings > 1)
- c->x86_max_cores /= smp_num_siblings;
- }
- /*
- * In case leaf B is available, use it to derive
- * topology information.
- */
- err = detect_extended_topology(c);
- if (!err)
- c->x86_coreid_bits = get_count_order(c->x86_max_cores);
- cacheinfo_amd_init_llc_id(c, cpu);
- } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
- u64 value;
- rdmsrl(MSR_FAM10H_NODE_ID, value);
- c->cpu_die_id = value & 7;
- per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
- } else
- return;
- if (nodes_per_socket > 1) {
- set_cpu_cap(c, X86_FEATURE_AMD_DCM);
- legacy_fixup_core_id(c);
- }
- }
- /*
- * 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 amd_detect_cmp(struct cpuinfo_x86 *c)
- {
- unsigned bits;
- int cpu = smp_processor_id();
- bits = c->x86_coreid_bits;
- /* Low order bits define the core id (index of core in socket) */
- c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
- /* Convert the initial APIC ID into the socket ID */
- c->phys_proc_id = c->initial_apicid >> bits;
- /* use socket ID also for last level cache */
- per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
- }
- u32 amd_get_nodes_per_socket(void)
- {
- return nodes_per_socket;
- }
- EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
- static void srat_detect_node(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_NUMA
- int cpu = smp_processor_id();
- int node;
- unsigned apicid = c->apicid;
- node = numa_cpu_node(cpu);
- if (node == NUMA_NO_NODE)
- node = get_llc_id(cpu);
- /*
- * On multi-fabric platform (e.g. Numascale NumaChip) a
- * platform-specific handler needs to be called to fixup some
- * IDs of the CPU.
- */
- if (x86_cpuinit.fixup_cpu_id)
- x86_cpuinit.fixup_cpu_id(c, node);
- if (!node_online(node)) {
- /*
- * Two possibilities here:
- *
- * - The CPU is missing memory and no node was created. In
- * that case try picking one from a nearby CPU.
- *
- * - The APIC IDs differ from the HyperTransport node IDs
- * which the K8 northbridge parsing fills in. Assume
- * they are all increased by a constant offset, but in
- * the same order as the HT nodeids. If that doesn't
- * result in a usable node fall back to the path for the
- * previous case.
- *
- * This workaround operates directly on the mapping between
- * APIC ID and NUMA node, assuming certain relationship
- * between APIC ID, HT node ID and NUMA topology. As going
- * through CPU mapping may alter the outcome, directly
- * access __apicid_to_node[].
- */
- int ht_nodeid = c->initial_apicid;
- if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
- node = __apicid_to_node[ht_nodeid];
- /* Pick a nearby node */
- if (!node_online(node))
- node = nearby_node(apicid);
- }
- numa_set_node(cpu, node);
- #endif
- }
- static void early_init_amd_mc(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_SMP
- unsigned bits, ecx;
- /* Multi core CPU? */
- if (c->extended_cpuid_level < 0x80000008)
- return;
- ecx = cpuid_ecx(0x80000008);
- c->x86_max_cores = (ecx & 0xff) + 1;
- /* CPU telling us the core id bits shift? */
- bits = (ecx >> 12) & 0xF;
- /* Otherwise recompute */
- if (bits == 0) {
- while ((1 << bits) < c->x86_max_cores)
- bits++;
- }
- c->x86_coreid_bits = bits;
- #endif
- }
- static void bsp_init_amd(struct cpuinfo_x86 *c)
- {
- if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
- if (c->x86 > 0x10 ||
- (c->x86 == 0x10 && c->x86_model >= 0x2)) {
- u64 val;
- rdmsrl(MSR_K7_HWCR, val);
- if (!(val & BIT(24)))
- pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
- }
- }
- if (c->x86 == 0x15) {
- unsigned long upperbit;
- u32 cpuid, assoc;
- cpuid = cpuid_edx(0x80000005);
- assoc = cpuid >> 16 & 0xff;
- upperbit = ((cpuid >> 24) << 10) / assoc;
- va_align.mask = (upperbit - 1) & PAGE_MASK;
- va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
- /* A random value per boot for bit slice [12:upper_bit) */
- va_align.bits = get_random_u32() & va_align.mask;
- }
- if (cpu_has(c, X86_FEATURE_MWAITX))
- use_mwaitx_delay();
- if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
- u32 ecx;
- ecx = cpuid_ecx(0x8000001e);
- __max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
- } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
- u64 value;
- rdmsrl(MSR_FAM10H_NODE_ID, value);
- __max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
- }
- if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
- !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
- c->x86 >= 0x15 && c->x86 <= 0x17) {
- unsigned int bit;
- switch (c->x86) {
- case 0x15: bit = 54; break;
- case 0x16: bit = 33; break;
- case 0x17: bit = 10; break;
- default: return;
- }
- /*
- * Try to cache the base value so further operations can
- * avoid RMW. If that faults, do not enable SSBD.
- */
- if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
- setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
- setup_force_cpu_cap(X86_FEATURE_SSBD);
- x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
- }
- }
- resctrl_cpu_detect(c);
- }
- static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
- {
- u64 msr;
- /*
- * BIOS support is required for SME and SEV.
- * For SME: If BIOS has enabled SME then adjust x86_phys_bits by
- * the SME physical address space reduction value.
- * If BIOS has not enabled SME then don't advertise the
- * SME feature (set in scattered.c).
- * If the kernel has not enabled SME via any means then
- * don't advertise the SME feature.
- * For SEV: If BIOS has not enabled SEV then don't advertise the
- * SEV and SEV_ES feature (set in scattered.c).
- *
- * In all cases, since support for SME and SEV requires long mode,
- * don't advertise the feature under CONFIG_X86_32.
- */
- if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
- /* Check if memory encryption is enabled */
- rdmsrl(MSR_AMD64_SYSCFG, msr);
- if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
- goto clear_all;
- /*
- * Always adjust physical address bits. Even though this
- * will be a value above 32-bits this is still done for
- * CONFIG_X86_32 so that accurate values are reported.
- */
- c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
- if (IS_ENABLED(CONFIG_X86_32))
- goto clear_all;
- if (!sme_me_mask)
- setup_clear_cpu_cap(X86_FEATURE_SME);
- rdmsrl(MSR_K7_HWCR, msr);
- if (!(msr & MSR_K7_HWCR_SMMLOCK))
- goto clear_sev;
- return;
- clear_all:
- setup_clear_cpu_cap(X86_FEATURE_SME);
- clear_sev:
- setup_clear_cpu_cap(X86_FEATURE_SEV);
- setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
- }
- }
- static void early_init_amd(struct cpuinfo_x86 *c)
- {
- u64 value;
- u32 dummy;
- early_init_amd_mc(c);
- if (c->x86 >= 0xf)
- set_cpu_cap(c, X86_FEATURE_K8);
- rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
- /*
- * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
- * with P/T states and does not stop in deep C-states
- */
- if (c->x86_power & (1 << 8)) {
- set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
- set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
- }
- /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
- if (c->x86_power & BIT(12))
- set_cpu_cap(c, X86_FEATURE_ACC_POWER);
- /* Bit 14 indicates the Runtime Average Power Limit interface. */
- if (c->x86_power & BIT(14))
- set_cpu_cap(c, X86_FEATURE_RAPL);
- #ifdef CONFIG_X86_64
- set_cpu_cap(c, X86_FEATURE_SYSCALL32);
- #else
- /* Set MTRR capability flag if appropriate */
- if (c->x86 == 5)
- if (c->x86_model == 13 || c->x86_model == 9 ||
- (c->x86_model == 8 && c->x86_stepping >= 8))
- set_cpu_cap(c, X86_FEATURE_K6_MTRR);
- #endif
- #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
- /*
- * ApicID can always be treated as an 8-bit value for AMD APIC versions
- * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
- * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
- * after 16h.
- */
- if (boot_cpu_has(X86_FEATURE_APIC)) {
- if (c->x86 > 0x16)
- set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
- else if (c->x86 >= 0xf) {
- /* check CPU config space for extended APIC ID */
- unsigned int val;
- val = read_pci_config(0, 24, 0, 0x68);
- if ((val >> 17 & 0x3) == 0x3)
- set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
- }
- }
- #endif
- /*
- * This is only needed to tell the kernel whether to use VMCALL
- * and VMMCALL. VMMCALL is never executed except under virt, so
- * we can set it unconditionally.
- */
- set_cpu_cap(c, X86_FEATURE_VMMCALL);
- /* F16h erratum 793, CVE-2013-6885 */
- if (c->x86 == 0x16 && c->x86_model <= 0xf)
- msr_set_bit(MSR_AMD64_LS_CFG, 15);
- /*
- * Check whether the machine is affected by erratum 400. This is
- * used to select the proper idle routine and to enable the check
- * whether the machine is affected in arch_post_acpi_init(), which
- * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
- */
- if (cpu_has_amd_erratum(c, amd_erratum_400))
- set_cpu_bug(c, X86_BUG_AMD_E400);
- early_detect_mem_encrypt(c);
- /* Re-enable TopologyExtensions if switched off by BIOS */
- if (c->x86 == 0x15 &&
- (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
- !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_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
- }
- }
- }
- if (cpu_has(c, X86_FEATURE_TOPOEXT))
- smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
- }
- static void init_amd_k8(struct cpuinfo_x86 *c)
- {
- u32 level;
- u64 value;
- /* On C+ stepping K8 rep microcode works well for copy/memset */
- level = cpuid_eax(1);
- if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
- set_cpu_cap(c, X86_FEATURE_REP_GOOD);
- /*
- * Some BIOSes incorrectly force this feature, but only K8 revision D
- * (model = 0x14) and later actually support it.
- * (AMD Erratum #110, docId: 25759).
- */
- if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
- clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
- if (!rdmsrl_amd_safe(0xc001100d, &value)) {
- value &= ~BIT_64(32);
- wrmsrl_amd_safe(0xc001100d, value);
- }
- }
- if (!c->x86_model_id[0])
- strcpy(c->x86_model_id, "Hammer");
- #ifdef CONFIG_SMP
- /*
- * Disable TLB flush filter by setting HWCR.FFDIS on K8
- * bit 6 of msr C001_0015
- *
- * Errata 63 for SH-B3 steppings
- * Errata 122 for all steppings (F+ have it disabled by default)
- */
- msr_set_bit(MSR_K7_HWCR, 6);
- #endif
- set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
- }
- static void init_amd_gh(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_MMCONF_FAM10H
- /* do this for boot cpu */
- if (c == &boot_cpu_data)
- check_enable_amd_mmconf_dmi();
- fam10h_check_enable_mmcfg();
- #endif
- /*
- * 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, we do it here as suggested by the BKDG.
- *
- * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
- */
- msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
- /*
- * 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);
- }
- static void init_amd_ln(struct cpuinfo_x86 *c)
- {
- /*
- * Apply erratum 665 fix unconditionally so machines without a BIOS
- * fix work.
- */
- msr_set_bit(MSR_AMD64_DE_CFG, 31);
- }
- static bool rdrand_force;
- static int __init rdrand_cmdline(char *str)
- {
- if (!str)
- return -EINVAL;
- if (!strcmp(str, "force"))
- rdrand_force = true;
- else
- return -EINVAL;
- return 0;
- }
- early_param("rdrand", rdrand_cmdline);
- static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
- {
- /*
- * Saving of the MSR used to hide the RDRAND support during
- * suspend/resume is done by arch/x86/power/cpu.c, which is
- * dependent on CONFIG_PM_SLEEP.
- */
- if (!IS_ENABLED(CONFIG_PM_SLEEP))
- return;
- /*
- * The self-test can clear X86_FEATURE_RDRAND, so check for
- * RDRAND support using the CPUID function directly.
- */
- if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
- return;
- msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
- /*
- * Verify that the CPUID change has occurred in case the kernel is
- * running virtualized and the hypervisor doesn't support the MSR.
- */
- if (cpuid_ecx(1) & BIT(30)) {
- pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
- return;
- }
- clear_cpu_cap(c, X86_FEATURE_RDRAND);
- pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
- }
- static void init_amd_jg(struct cpuinfo_x86 *c)
- {
- /*
- * Some BIOS implementations do not restore proper RDRAND support
- * across suspend and resume. Check on whether to hide the RDRAND
- * instruction support via CPUID.
- */
- clear_rdrand_cpuid_bit(c);
- }
- static void init_amd_bd(struct cpuinfo_x86 *c)
- {
- u64 value;
- /*
- * The way access filter has a performance penalty on some workloads.
- * Disable it on the affected CPUs.
- */
- if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
- if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
- value |= 0x1E;
- wrmsrl_safe(MSR_F15H_IC_CFG, value);
- }
- }
- /*
- * Some BIOS implementations do not restore proper RDRAND support
- * across suspend and resume. Check on whether to hide the RDRAND
- * instruction support via CPUID.
- */
- clear_rdrand_cpuid_bit(c);
- }
- void init_spectral_chicken(struct cpuinfo_x86 *c)
- {
- #ifdef CONFIG_CPU_UNRET_ENTRY
- u64 value;
- /*
- * On Zen2 we offer this chicken (bit) on the altar of Speculation.
- *
- * This suppresses speculation from the middle of a basic block, i.e. it
- * suppresses non-branch predictions.
- *
- * We use STIBP as a heuristic to filter out Zen2 from the rest of F17H
- */
- if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && cpu_has(c, X86_FEATURE_AMD_STIBP)) {
- if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
- value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
- wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
- }
- }
- #endif
- /*
- * Work around Erratum 1386. The XSAVES instruction malfunctions in
- * certain circumstances on Zen1/2 uarch, and not all parts have had
- * updated microcode at the time of writing (March 2023).
- *
- * Affected parts all have no supervisor XSAVE states, meaning that
- * the XSAVEC instruction (which works fine) is equivalent.
- */
- clear_cpu_cap(c, X86_FEATURE_XSAVES);
- }
- static void init_amd_zn(struct cpuinfo_x86 *c)
- {
- set_cpu_cap(c, X86_FEATURE_ZEN);
- #ifdef CONFIG_NUMA
- node_reclaim_distance = 32;
- #endif
- /* Fix up CPUID bits, but only if not virtualised. */
- if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
- /* Erratum 1076: CPB feature bit not being set in CPUID. */
- if (!cpu_has(c, X86_FEATURE_CPB))
- set_cpu_cap(c, X86_FEATURE_CPB);
- /*
- * Zen3 (Fam19 model < 0x10) parts are not susceptible to
- * Branch Type Confusion, but predate the allocation of the
- * BTC_NO bit.
- */
- if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
- set_cpu_cap(c, X86_FEATURE_BTC_NO);
- }
- }
- static bool cpu_has_zenbleed_microcode(void)
- {
- u32 good_rev = 0;
- switch (boot_cpu_data.x86_model) {
- case 0x30 ... 0x3f: good_rev = 0x0830107a; break;
- case 0x60 ... 0x67: good_rev = 0x0860010b; break;
- case 0x68 ... 0x6f: good_rev = 0x08608105; break;
- case 0x70 ... 0x7f: good_rev = 0x08701032; break;
- case 0xa0 ... 0xaf: good_rev = 0x08a00008; break;
- default:
- return false;
- break;
- }
- if (boot_cpu_data.microcode < good_rev)
- return false;
- return true;
- }
- static void zenbleed_check(struct cpuinfo_x86 *c)
- {
- if (!cpu_has_amd_erratum(c, amd_zenbleed))
- return;
- if (cpu_has(c, X86_FEATURE_HYPERVISOR))
- return;
- if (!cpu_has(c, X86_FEATURE_AVX))
- return;
- if (!cpu_has_zenbleed_microcode()) {
- pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
- msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
- } else {
- msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
- }
- }
- static void init_amd(struct cpuinfo_x86 *c)
- {
- early_init_amd(c);
- /*
- * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
- * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
- */
- clear_cpu_cap(c, 0*32+31);
- if (c->x86 >= 0x10)
- set_cpu_cap(c, X86_FEATURE_REP_GOOD);
- /* get apicid instead of initial apic id from cpuid */
- c->apicid = hard_smp_processor_id();
- /* K6s reports MCEs but don't actually have all the MSRs */
- if (c->x86 < 6)
- clear_cpu_cap(c, X86_FEATURE_MCE);
- switch (c->x86) {
- case 4: init_amd_k5(c); break;
- case 5: init_amd_k6(c); break;
- case 6: init_amd_k7(c); break;
- case 0xf: init_amd_k8(c); break;
- case 0x10: init_amd_gh(c); break;
- case 0x12: init_amd_ln(c); break;
- case 0x15: init_amd_bd(c); break;
- case 0x16: init_amd_jg(c); break;
- case 0x17: init_spectral_chicken(c);
- fallthrough;
- case 0x19: init_amd_zn(c); break;
- }
- /*
- * Enable workaround for FXSAVE leak on CPUs
- * without a XSaveErPtr feature
- */
- if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
- set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
- cpu_detect_cache_sizes(c);
- amd_detect_cmp(c);
- amd_get_topology(c);
- srat_detect_node(c);
- init_amd_cacheinfo(c);
- if (cpu_has(c, X86_FEATURE_XMM2)) {
- /*
- * Use LFENCE for execution serialization. On families which
- * don't have that MSR, LFENCE is already serializing.
- * msr_set_bit() uses the safe accessors, too, even if the MSR
- * is not present.
- */
- msr_set_bit(MSR_AMD64_DE_CFG,
- MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
- /* A serializing LFENCE stops RDTSC speculation */
- set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
- }
- /*
- * Family 0x12 and above processors have APIC timer
- * running in deep C states.
- */
- if (c->x86 > 0x11)
- set_cpu_cap(c, X86_FEATURE_ARAT);
- /* 3DNow or LM implies PREFETCHW */
- if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
- if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
- set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
- /* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
- if (!cpu_has(c, X86_FEATURE_XENPV))
- set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
- /*
- * Turn on the Instructions Retired free counter on machines not
- * susceptible to erratum #1054 "Instructions Retired Performance
- * Counter May Be Inaccurate".
- */
- if (cpu_has(c, X86_FEATURE_IRPERF) &&
- !cpu_has_amd_erratum(c, amd_erratum_1054))
- msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
- check_null_seg_clears_base(c);
- zenbleed_check(c);
- if (cpu_has_amd_erratum(c, amd_div0)) {
- pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
- setup_force_cpu_bug(X86_BUG_DIV0);
- }
- if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
- cpu_has_amd_erratum(c, amd_erratum_1485))
- msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
- }
- #ifdef CONFIG_X86_32
- static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
- {
- /* AMD errata T13 (order #21922) */
- if (c->x86 == 6) {
- /* Duron Rev A0 */
- if (c->x86_model == 3 && c->x86_stepping == 0)
- size = 64;
- /* Tbird rev A1/A2 */
- if (c->x86_model == 4 &&
- (c->x86_stepping == 0 || c->x86_stepping == 1))
- size = 256;
- }
- return size;
- }
- #endif
- 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;
- }
- static const struct cpu_dev amd_cpu_dev = {
- .c_vendor = "AMD",
- .c_ident = { "AuthenticAMD" },
- #ifdef CONFIG_X86_32
- .legacy_models = {
- { .family = 4, .model_names =
- {
- [3] = "486 DX/2",
- [7] = "486 DX/2-WB",
- [8] = "486 DX/4",
- [9] = "486 DX/4-WB",
- [14] = "Am5x86-WT",
- [15] = "Am5x86-WB"
- }
- },
- },
- .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,
- };
- cpu_dev_register(amd_cpu_dev);
- void set_dr_addr_mask(unsigned long mask, int dr)
- {
- if (!boot_cpu_has(X86_FEATURE_BPEXT))
- return;
- switch (dr) {
- case 0:
- wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
- break;
- case 1:
- case 2:
- case 3:
- wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
- break;
- default:
- break;
- }
- }
- u32 amd_get_highest_perf(void)
- {
- struct cpuinfo_x86 *c = &boot_cpu_data;
- if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
- (c->x86_model >= 0x70 && c->x86_model < 0x80)))
- return 166;
- if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
- (c->x86_model >= 0x40 && c->x86_model < 0x70)))
- return 166;
- return 255;
- }
- EXPORT_SYMBOL_GPL(amd_get_highest_perf);
- bool cpu_has_ibpb_brtype_microcode(void)
- {
- switch (boot_cpu_data.x86) {
- /* Zen1/2 IBPB flushes branch type predictions too. */
- case 0x17:
- return boot_cpu_has(X86_FEATURE_AMD_IBPB);
- case 0x19:
- /* Poke the MSR bit on Zen3/4 to check its presence. */
- if (!wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
- setup_force_cpu_cap(X86_FEATURE_SBPB);
- return true;
- } else {
- return false;
- }
- default:
- return false;
- }
- }
- static void zenbleed_check_cpu(void *unused)
- {
- struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
- zenbleed_check(c);
- }
- void amd_check_microcode(void)
- {
- if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
- return;
- on_each_cpu(zenbleed_check_cpu, NULL, 1);
- }
- /*
- * Issue a DIV 0/1 insn to clear any division data from previous DIV
- * operations.
- */
- void noinstr amd_clear_divider(void)
- {
- asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
- :: "a" (0), "d" (0), "r" (1));
- }
- EXPORT_SYMBOL_GPL(amd_clear_divider);
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