diff options
| -rw-r--r-- | arch/x86/include/asm/memtype.h | 5 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/cacheinfo.c | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/mtrr/mtrr.c | 12 | ||||
| -rw-r--r-- | arch/x86/kernel/setup.c | 13 | ||||
| -rw-r--r-- | arch/x86/mm/pat/memtype.c | 152 |
5 files changed, 57 insertions, 128 deletions
diff --git a/arch/x86/include/asm/memtype.h b/arch/x86/include/asm/memtype.h index 9ca760e430b9..113b2fa51849 100644 --- a/arch/x86/include/asm/memtype.h +++ b/arch/x86/include/asm/memtype.h @@ -6,9 +6,8 @@ #include <asm/pgtable_types.h> extern bool pat_enabled(void); -extern void pat_disable(const char *reason); -extern void pat_init(void); -extern void init_cache_modes(void); +extern void pat_bp_init(void); +extern void pat_cpu_init(void); extern int memtype_reserve(u64 start, u64 end, enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm); diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c index 4e155bd2574f..c830f853e3b1 100644 --- a/arch/x86/kernel/cpu/cacheinfo.c +++ b/arch/x86/kernel/cpu/cacheinfo.c @@ -1133,7 +1133,7 @@ static void cache_cpu_init(void) mtrr_generic_set_state(); if (memory_caching_control & CACHE_PAT) - pat_init(); + pat_cpu_init(); cache_enable(); local_irq_restore(flags); @@ -1162,6 +1162,7 @@ static int cache_rendezvous_handler(void *unused) void __init cache_bp_init(void) { mtrr_bp_init(); + pat_bp_init(); if (memory_caching_control) cache_cpu_init(); diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c index 99b6973a69b4..8403daf34158 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.c +++ b/arch/x86/kernel/cpu/mtrr/mtrr.c @@ -725,7 +725,7 @@ void __init mtrr_bp_init(void) if (mtrr_if == &generic_mtrr_ops) { /* BIOS may override */ if (get_mtrr_state()) { - memory_caching_control |= CACHE_MTRR | CACHE_PAT; + memory_caching_control |= CACHE_MTRR; changed_by_mtrr_cleanup = mtrr_cleanup(phys_addr); } else { mtrr_if = NULL; @@ -733,16 +733,8 @@ void __init mtrr_bp_init(void) } } - if (!mtrr_enabled()) { + if (!mtrr_enabled()) pr_info("Disabled\n"); - - /* - * PAT initialization relies on MTRR's rendezvous handler. - * Skip PAT init until the handler can initialize both - * features independently. - */ - pat_disable("MTRRs disabled, skipping PAT initialization too."); - } } /** diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index e0e185ee0229..aacaa96f0195 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -1075,24 +1075,13 @@ void __init setup_arch(char **cmdline_p) max_pfn = e820__end_of_ram_pfn(); /* update e820 for memory not covered by WB MTRRs */ - if (IS_ENABLED(CONFIG_MTRR)) - cache_bp_init(); - else - pat_disable("PAT support disabled because CONFIG_MTRR is disabled in the kernel."); - + cache_bp_init(); if (mtrr_trim_uncached_memory(max_pfn)) max_pfn = e820__end_of_ram_pfn(); max_possible_pfn = max_pfn; /* - * This call is required when the CPU does not support PAT. If - * mtrr_bp_init() invoked it already via pat_init() the call has no - * effect. - */ - init_cache_modes(); - - /* * Define random base addresses for memory sections after max_pfn is * defined and before each memory section base is used. */ diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index 66a209f7eb86..9aab17d660cd 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -43,6 +43,7 @@ #include <linux/rbtree.h> #include <asm/cacheflush.h> +#include <asm/cacheinfo.h> #include <asm/processor.h> #include <asm/tlbflush.h> #include <asm/x86_init.h> @@ -60,41 +61,34 @@ #undef pr_fmt #define pr_fmt(fmt) "" fmt -static bool __read_mostly pat_bp_initialized; static bool __read_mostly pat_disabled = !IS_ENABLED(CONFIG_X86_PAT); -static bool __initdata pat_force_disabled = !IS_ENABLED(CONFIG_X86_PAT); -static bool __read_mostly pat_bp_enabled; -static bool __read_mostly pat_cm_initialized; +static u64 __ro_after_init pat_msr_val; /* * PAT support is enabled by default, but can be disabled for * various user-requested or hardware-forced reasons: */ -void pat_disable(const char *msg_reason) +static void __init pat_disable(const char *msg_reason) { if (pat_disabled) return; - if (pat_bp_initialized) { - WARN_ONCE(1, "x86/PAT: PAT cannot be disabled after initialization\n"); - return; - } - pat_disabled = true; pr_info("x86/PAT: %s\n", msg_reason); + + memory_caching_control &= ~CACHE_PAT; } static int __init nopat(char *str) { pat_disable("PAT support disabled via boot option."); - pat_force_disabled = true; return 0; } early_param("nopat", nopat); bool pat_enabled(void) { - return pat_bp_enabled; + return !pat_disabled; } EXPORT_SYMBOL_GPL(pat_enabled); @@ -192,7 +186,8 @@ enum { #define CM(c) (_PAGE_CACHE_MODE_ ## c) -static enum page_cache_mode pat_get_cache_mode(unsigned pat_val, char *msg) +static enum page_cache_mode __init pat_get_cache_mode(unsigned int pat_val, + char *msg) { enum page_cache_mode cache; char *cache_mode; @@ -219,14 +214,12 @@ static enum page_cache_mode pat_get_cache_mode(unsigned pat_val, char *msg) * configuration. * Using lower indices is preferred, so we start with highest index. */ -static void __init_cache_modes(u64 pat) +static void __init init_cache_modes(u64 pat) { enum page_cache_mode cache; char pat_msg[33]; int i; - WARN_ON_ONCE(pat_cm_initialized); - pat_msg[32] = 0; for (i = 7; i >= 0; i--) { cache = pat_get_cache_mode((pat >> (i * 8)) & 7, @@ -234,34 +227,9 @@ static void __init_cache_modes(u64 pat) update_cache_mode_entry(i, cache); } pr_info("x86/PAT: Configuration [0-7]: %s\n", pat_msg); - - pat_cm_initialized = true; } -#define PAT(x, y) ((u64)PAT_ ## y << ((x)*8)) - -static void pat_bp_init(u64 pat) -{ - u64 tmp_pat; - - if (!boot_cpu_has(X86_FEATURE_PAT)) { - pat_disable("PAT not supported by the CPU."); - return; - } - - rdmsrl(MSR_IA32_CR_PAT, tmp_pat); - if (!tmp_pat) { - pat_disable("PAT support disabled by the firmware."); - return; - } - - wrmsrl(MSR_IA32_CR_PAT, pat); - pat_bp_enabled = true; - - __init_cache_modes(pat); -} - -static void pat_ap_init(u64 pat) +void pat_cpu_init(void) { if (!boot_cpu_has(X86_FEATURE_PAT)) { /* @@ -271,30 +239,39 @@ static void pat_ap_init(u64 pat) panic("x86/PAT: PAT enabled, but not supported by secondary CPU\n"); } - wrmsrl(MSR_IA32_CR_PAT, pat); + wrmsrl(MSR_IA32_CR_PAT, pat_msr_val); } -void __init init_cache_modes(void) +/** + * pat_bp_init - Initialize the PAT MSR value and PAT table + * + * This function initializes PAT MSR value and PAT table with an OS-defined + * value to enable additional cache attributes, WC, WT and WP. + * + * This function prepares the calls of pat_cpu_init() via cache_cpu_init() + * on all CPUs. + */ +void __init pat_bp_init(void) { - u64 pat = 0; + struct cpuinfo_x86 *c = &boot_cpu_data; +#define PAT(p0, p1, p2, p3, p4, p5, p6, p7) \ + (((u64)PAT_ ## p0) | ((u64)PAT_ ## p1 << 8) | \ + ((u64)PAT_ ## p2 << 16) | ((u64)PAT_ ## p3 << 24) | \ + ((u64)PAT_ ## p4 << 32) | ((u64)PAT_ ## p5 << 40) | \ + ((u64)PAT_ ## p6 << 48) | ((u64)PAT_ ## p7 << 56)) - if (pat_cm_initialized) - return; - if (boot_cpu_has(X86_FEATURE_PAT)) { - /* - * CPU supports PAT. Set PAT table to be consistent with - * PAT MSR. This case supports "nopat" boot option, and - * virtual machine environments which support PAT without - * MTRRs. In specific, Xen has unique setup to PAT MSR. - * - * If PAT MSR returns 0, it is considered invalid and emulates - * as No PAT. - */ - rdmsrl(MSR_IA32_CR_PAT, pat); - } + if (!IS_ENABLED(CONFIG_X86_PAT)) + pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n"); + + if (!cpu_feature_enabled(X86_FEATURE_PAT)) + pat_disable("PAT not supported by the CPU."); + else + rdmsrl(MSR_IA32_CR_PAT, pat_msr_val); + + if (!pat_msr_val) { + pat_disable("PAT support disabled by the firmware."); - if (!pat) { /* * No PAT. Emulate the PAT table that corresponds to the two * cache bits, PWT (Write Through) and PCD (Cache Disable). @@ -313,40 +290,17 @@ void __init init_cache_modes(void) * NOTE: When WC or WP is used, it is redirected to UC- per * the default setup in __cachemode2pte_tbl[]. */ - pat = PAT(0, WB) | PAT(1, WT) | PAT(2, UC_MINUS) | PAT(3, UC) | - PAT(4, WB) | PAT(5, WT) | PAT(6, UC_MINUS) | PAT(7, UC); - } else if (!pat_force_disabled && cpu_feature_enabled(X86_FEATURE_HYPERVISOR)) { - /* - * Clearly PAT is enabled underneath. Allow pat_enabled() to - * reflect this. - */ - pat_bp_enabled = true; + pat_msr_val = PAT(WB, WT, UC_MINUS, UC, WB, WT, UC_MINUS, UC); } - __init_cache_modes(pat); -} - -/** - * pat_init - Initialize the PAT MSR and PAT table on the current CPU - * - * This function initializes PAT MSR and PAT table with an OS-defined value - * to enable additional cache attributes, WC, WT and WP. - * - * This function must be called on all CPUs using the specific sequence of - * operations defined in Intel SDM. mtrr_rendezvous_handler() provides this - * procedure for PAT. - */ -void pat_init(void) -{ - u64 pat; - struct cpuinfo_x86 *c = &boot_cpu_data; - -#ifndef CONFIG_X86_PAT - pr_info_once("x86/PAT: PAT support disabled because CONFIG_X86_PAT is disabled in the kernel.\n"); -#endif - - if (pat_disabled) + /* + * Xen PV doesn't allow to set PAT MSR, but all cache modes are + * supported. + */ + if (pat_disabled || cpu_feature_enabled(X86_FEATURE_XENPV)) { + init_cache_modes(pat_msr_val); return; + } if ((c->x86_vendor == X86_VENDOR_INTEL) && (((c->x86 == 0x6) && (c->x86_model <= 0xd)) || @@ -371,8 +325,7 @@ void pat_init(void) * NOTE: When WT or WP is used, it is redirected to UC- per * the default setup in __cachemode2pte_tbl[]. */ - pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) | - PAT(4, WB) | PAT(5, WC) | PAT(6, UC_MINUS) | PAT(7, UC); + pat_msr_val = PAT(WB, WC, UC_MINUS, UC, WB, WC, UC_MINUS, UC); } else { /* * Full PAT support. We put WT in slot 7 to improve @@ -400,19 +353,14 @@ void pat_init(void) * The reserved slots are unused, but mapped to their * corresponding types in the presence of PAT errata. */ - pat = PAT(0, WB) | PAT(1, WC) | PAT(2, UC_MINUS) | PAT(3, UC) | - PAT(4, WB) | PAT(5, WP) | PAT(6, UC_MINUS) | PAT(7, WT); + pat_msr_val = PAT(WB, WC, UC_MINUS, UC, WB, WP, UC_MINUS, WT); } - if (!pat_bp_initialized) { - pat_bp_init(pat); - pat_bp_initialized = true; - } else { - pat_ap_init(pat); - } -} + memory_caching_control |= CACHE_PAT; + init_cache_modes(pat_msr_val); #undef PAT +} static DEFINE_SPINLOCK(memtype_lock); /* protects memtype accesses */ |