Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1309 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..c1d09c884
--- /dev/null
+++ b/arch/x86/kernel/cpu/amd.c
@@ -0,0 +1,1309 @@
+// 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);