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-rw-r--r--arch/x86/kernel/cpu/amd.c1177
1 files changed, 1177 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
new file mode 100644
index 000000000..98c23126f
--- /dev/null
+++ b/arch/x86/kernel/cpu/amd.c
@@ -0,0 +1,1177 @@
+#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 <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/pci-direct.h>
+#include <asm/delay.h>
+
+#ifdef CONFIG_X86_64
+# include <asm/mmconfig.h>
+# include <asm/set_memory.h>
+#endif
+
+#include "cpu.h"
+
+static const int amd_erratum_383[];
+static const int amd_erratum_400[];
+static const int amd_erratum_1054[];
+static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
+
+/*
+ * 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;
+
+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..
+ */
+
+extern __visible void vide(void);
+__asm__(".globl vide\n"
+ ".type vide, @function\n"
+ ".align 4\n"
+ "vide: ret\n");
+
+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;
+}
+
+
+static void amd_get_topology_early(struct cpuinfo_x86 *c)
+{
+ if (cpu_has(c, X86_FEATURE_TOPOEXT))
+ smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
+}
+
+/*
+ * 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)
+{
+ u8 node_id;
+ 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);
+
+ node_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, node_id);
+
+ } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
+ u64 value;
+
+ rdmsrl(MSR_FAM10H_NODE_ID, value);
+ node_id = value & 7;
+
+ per_cpu(cpu_llc_id, cpu) = node_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->phys_proc_id;
+}
+
+u16 amd_get_nb_id(int cpu)
+{
+ return per_cpu(cpu_llc_id, cpu);
+}
+EXPORT_SYMBOL_GPL(amd_get_nb_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 = per_cpu(cpu_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)
+{
+
+#ifdef CONFIG_X86_64
+ if (c->x86 >= 0xf) {
+ unsigned long long tseg;
+
+ /*
+ * Split up direct mapping around the TSEG SMM area.
+ * Don't do it for gbpages because there seems very little
+ * benefit in doing so.
+ */
+ if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
+ unsigned long pfn = tseg >> PAGE_SHIFT;
+
+ pr_debug("tseg: %010llx\n", tseg);
+ if (pfn_range_is_mapped(pfn, pfn + 1))
+ set_memory_4k((unsigned long)__va(tseg), 1);
+ }
+ }
+#endif
+
+ 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_int() & 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);
+ nodes_per_socket = ((ecx >> 8) & 7) + 1;
+ } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
+ u64 value;
+
+ rdmsrl(MSR_FAM10H_NODE_ID, value);
+ 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;
+ }
+ }
+}
+
+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).
+ * For SEV: If BIOS has not enabled SEV then don't advertise the
+ * SEV 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_K8_SYSCFG, msr);
+ if (!(msr & MSR_K8_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;
+
+ 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);
+ }
+}
+
+static void early_init_amd(struct cpuinfo_x86 *c)
+{
+ u64 value;
+ u32 dummy;
+
+ early_init_amd_mc(c);
+
+#ifdef CONFIG_X86_32
+ if (c->x86 == 6)
+ set_cpu_cap(c, X86_FEATURE_K7);
+#endif
+
+ 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);
+
+#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");
+ }
+ }
+ }
+
+ amd_get_topology_early(c);
+}
+
+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);
+}
+
+#define MSR_AMD64_DE_CFG 0xC0011029
+
+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 nordrand option 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);
+}
+
+static void init_amd_zn(struct cpuinfo_x86 *c)
+{
+ set_cpu_cap(c, X86_FEATURE_ZEN);
+
+ /*
+ * Fix erratum 1076: CPB feature bit not being set in CPUID.
+ * Always set it, except when running under a hypervisor.
+ */
+ if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_CPB))
+ set_cpu_cap(c, X86_FEATURE_CPB);
+}
+
+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_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)) {
+ unsigned long long val;
+ int ret;
+
+ /*
+ * A serializing LFENCE has less overhead than MFENCE, so
+ * use it 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_F10H_DECFG,
+ MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT);
+
+ /*
+ * Verify that the MSR write was successful (could be running
+ * under a hypervisor) and only then assume that LFENCE is
+ * serializing.
+ */
+ ret = rdmsrl_safe(MSR_F10H_DECFG, &val);
+ if (!ret && (val & MSR_F10H_DECFG_LFENCE_SERIALIZE)) {
+ /* A serializing LFENCE stops RDTSC speculation */
+ set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
+ } else {
+ /* MFENCE stops RDTSC speculation */
+ set_cpu_cap(c, X86_FEATURE_MFENCE_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);
+}
+
+#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);
+
+/*
+ * 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 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;
+}
+
+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;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 13:17:11 +0000