From 655f231bde27f5201b5d35a95bc39f26e34899a3 Mon Sep 17 00:00:00 2001 From: Babu Moger Date: Mon, 15 Jan 2024 16:52:27 -0600 Subject: [PATCH] x86/resctrl: Remove hard-coded memory bandwidth limit [ Upstream commit 0976783bb123f30981bc1e7a14d9626a6f63aeac ] The QOS Memory Bandwidth Enforcement Limit is reported by CPUID_Fn80000020_EAX_x01 and CPUID_Fn80000020_EAX_x02: Bits Description 31:0 BW_LEN: Size of the QOS Memory Bandwidth Enforcement Limit. Newer processors can support higher bandwidth limit than the current hard-coded value. Remove latter and detect using CPUID instead. Also, update the register variables eax and edx to match the AMD CPUID definition. The CPUID details are documented in the Processor Programming Reference (PPR) Vol 1.1 for AMD Family 19h Model 11h B1 - 55901 Rev 0.25 in the Link tag below. Fixes: 4d05bf71f157 ("x86/resctrl: Introduce AMD QOS feature") Signed-off-by: Babu Moger Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 Link: https://lore.kernel.org/r/c26a8ca79d399ed076cf8bf2e9fbc58048808289.1705359148.git.babu.moger@amd.com Signed-off-by: Sasha Levin --- arch/x86/kernel/cpu/resctrl/core.c | 10 ++++------ arch/x86/kernel/cpu/resctrl/internal.h | 1 - 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 030d3b409768..8073fd304293 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -230,9 +230,7 @@ static bool __get_mem_config_intel(struct rdt_resource *r) static bool __rdt_get_mem_config_amd(struct rdt_resource *r) { struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r); - union cpuid_0x10_3_eax eax; - union cpuid_0x10_x_edx edx; - u32 ebx, ecx, subleaf; + u32 eax, ebx, ecx, edx, subleaf; /* * Query CPUID_Fn80000020_EDX_x01 for MBA and @@ -240,9 +238,9 @@ static bool __rdt_get_mem_config_amd(struct rdt_resource *r) */ subleaf = (r->rid == RDT_RESOURCE_SMBA) ? 2 : 1; - cpuid_count(0x80000020, subleaf, &eax.full, &ebx, &ecx, &edx.full); - hw_res->num_closid = edx.split.cos_max + 1; - r->default_ctrl = MAX_MBA_BW_AMD; + cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx); + hw_res->num_closid = edx + 1; + r->default_ctrl = 1 << eax; /* AMD does not use delay */ r->membw.delay_linear = false; diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index 85ceaf9a31ac..81d90f1a8ce5 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -18,7 +18,6 @@ #define MBM_OVERFLOW_INTERVAL 1000 #define MAX_MBA_BW 100u #define MBA_IS_LINEAR 0x4 -#define MAX_MBA_BW_AMD 0x800 #define MBM_CNTR_WIDTH_OFFSET_AMD 20 #define RMID_VAL_ERROR BIT_ULL(63)