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authorMark Brown <broonie@kernel.org>2023-08-18 22:46:19 +0100
committerMark Brown <broonie@kernel.org>2023-08-18 22:46:19 +0100
commitab4724302feedcd33633fd409667a8ee0016f13d (patch)
tree245c7082ca66780da02df0b7cedc91a5090b795f /arch/x86/kernel/cpu/amd.c
parent46f53bde6e69edf8a2e0943babb3f160b30ee436 (diff)
parentef75e767167a8f30c7690bc4689dba76329ee06e (diff)
Add cs42l43 PC focused SoundWire CODEC
Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>: This patch chain adds support for the Cirrus Logic cs42l43 PC focused SoundWire CODEC.
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r--arch/x86/kernel/cpu/amd.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 26ad7ca423e7..70f9d56f9305 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -73,8 +73,13 @@ static const int amd_erratum_1054[] =
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 bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
{
int osvw_id = *erratum++;
@@ -1130,6 +1135,11 @@ static void init_amd(struct cpuinfo_x86 *c)
WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
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);
+ }
}
#ifdef CONFIG_X86_32
@@ -1290,3 +1300,32 @@ void amd_check_microcode(void)
{
on_each_cpu(zenbleed_check_cpu, NULL, 1);
}
+
+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;
+ }
+}
+
+/*
+ * 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));
+}