#ifndef EARLYMTRR_C #define EARLYMTRR_C #include #include #include #include static void set_var_mtrr( unsigned reg, unsigned base, unsigned size, unsigned type) { /* Bit Bit 32-35 of MTRRphysMask should be set to 1 */ /* FIXME: It only support 4G less range */ msr_t basem, maskm; basem.lo = base | type; basem.hi = 0; wrmsr(MTRRphysBase_MSR(reg), basem); maskm.lo = ~(size - 1) | MTRRphysMaskValid; maskm.hi = (1 << (CONFIG_CPU_ADDR_BITS - 32)) - 1; wrmsr(MTRRphysMask_MSR(reg), maskm); } #if !defined(CONFIG_CACHE_AS_RAM) || (CONFIG_CACHE_AS_RAM == 0) static void cache_lbmem(int type) { /* Enable caching for 0 - 1MB using variable mtrr */ disable_cache(); set_var_mtrr(0, 0x00000000, CONFIG_RAMTOP, type); enable_cache(); } const int addr_det = 0; /* the fixed and variable MTTRs are power-up with random values, * clear them to MTRR_TYPE_UNCACHEABLE for safty. */ static void do_early_mtrr_init(const unsigned long *mtrr_msrs) { /* Precondition: * The cache is not enabled in cr0 nor in MTRRdefType_MSR * entry32.inc ensures the cache is not enabled in cr0 */ msr_t msr; const unsigned long *msr_addr; /* Inialize all of the relevant msrs to 0 */ msr.lo = 0; msr.hi = 0; unsigned long msr_nr; for(msr_addr = mtrr_msrs; (msr_nr = *msr_addr); msr_addr++) { wrmsr(msr_nr, msr); } #if defined(CONFIG_XIP_ROM_SIZE) /* enable write through caching so we can do execute in place * on the flash rom. * Determine address by calculating the XIP_ROM_SIZE sized area with * XIP_ROM_SIZE alignment that contains the global variable defined above; */ unsigned long f = (unsigned long)&addr_det & ~(CONFIG_XIP_ROM_SIZE - 1); set_var_mtrr(1, f, CONFIG_XIP_ROM_SIZE, MTRR_TYPE_WRBACK); #endif /* Set the default memory type and enable fixed and variable MTRRs */ /* Enable Variable MTRRs */ msr.hi = 0x00000000; msr.lo = 0x00000800; wrmsr(MTRRdefType_MSR, msr); } static inline void early_mtrr_init(void) { static const unsigned long mtrr_msrs[] = { /* fixed mtrr */ 0x250, 0x258, 0x259, 0x268, 0x269, 0x26A, 0x26B, 0x26C, 0x26D, 0x26E, 0x26F, /* var mtrr */ 0x200, 0x201, 0x202, 0x203, 0x204, 0x205, 0x206, 0x207, 0x208, 0x209, 0x20A, 0x20B, 0x20C, 0x20D, 0x20E, 0x20F, /* NULL end of table */ 0 }; disable_cache(); do_early_mtrr_init(mtrr_msrs); enable_cache(); } static inline int early_mtrr_init_detected(void) { msr_t msr; /* See if MTRR's are enabled. * a #RESET disables them while an #INIT * preserves their state. This works * on both Intel and AMD cpus, at least * according to the documentation. */ msr = rdmsr(MTRRdefType_MSR); return msr.lo & MTRRdefTypeEn; } #endif #endif /* EARLYMTRR_C */