diff options
Diffstat (limited to 'src/soc/intel/skylake/bootblock/cpu.c')
| -rw-r--r-- | src/soc/intel/skylake/bootblock/cpu.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/src/soc/intel/skylake/bootblock/cpu.c b/src/soc/intel/skylake/bootblock/cpu.c new file mode 100644 index 0000000000..3a47d13f0a --- /dev/null +++ b/src/soc/intel/skylake/bootblock/cpu.c @@ -0,0 +1,142 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2014 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <stdint.h> +#include <arch/cpu.h> +#include <cpu/x86/cache.h> +#include <cpu/x86/msr.h> +#include <cpu/x86/mtrr.h> +#include <arch/io.h> +#include <halt.h> +#include <cpu/intel/microcode/microcode.c> +#include <soc/rcba.h> +#include <soc/msr.h> + +static void set_var_mtrr( + unsigned reg, unsigned base, unsigned size, unsigned type) + +{ + /* Bit Bit 32-35 of MTRRphysMask should be set to 1 */ + 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); +} + +static void enable_rom_caching(void) +{ + msr_t msr; + + disable_cache(); + /* Why only top 4MiB ? */ + set_var_mtrr(1, CACHE_ROM_BASE, CACHE_ROM_SIZE, MTRR_TYPE_WRPROT); + enable_cache(); + + /* Enable Variable MTRRs */ + msr.hi = 0x00000000; + msr.lo = 0x00000800; + wrmsr(MTRRdefType_MSR, msr); +} + +static void bootblock_mdelay(int ms) +{ + u32 target = ms * 24 * 1000; + msr_t current; + msr_t start = rdmsr(MSR_COUNTER_24_MHZ); + + do { + current = rdmsr(MSR_COUNTER_24_MHZ); + } while ((current.lo - start.lo) < target); +} + +static void set_flex_ratio_to_tdp_nominal(void) +{ + msr_t flex_ratio, msr; + u32 soft_reset; + u8 nominal_ratio; + + /* Check for Flex Ratio support */ + flex_ratio = rdmsr(MSR_FLEX_RATIO); + if (!(flex_ratio.lo & FLEX_RATIO_EN)) + return; + + /* Check for >0 configurable TDPs */ + msr = rdmsr(MSR_PLATFORM_INFO); + if (((msr.hi >> 1) & 3) == 0) + return; + + /* Use nominal TDP ratio for flex ratio */ + msr = rdmsr(MSR_CONFIG_TDP_NOMINAL); + nominal_ratio = msr.lo & 0xff; + + /* See if flex ratio is already set to nominal TDP ratio */ + if (((flex_ratio.lo >> 8) & 0xff) == nominal_ratio) + return; + + /* Set flex ratio to nominal TDP ratio */ + flex_ratio.lo &= ~0xff00; + flex_ratio.lo |= nominal_ratio << 8; + flex_ratio.lo |= FLEX_RATIO_LOCK; + wrmsr(MSR_FLEX_RATIO, flex_ratio); + + /* Set flex ratio in soft reset data register bits 11:6. + * RCBA region is enabled in southbridge bootblock */ + soft_reset = RCBA32(SOFT_RESET_DATA); + soft_reset &= ~(0x3f << 6); + soft_reset |= (nominal_ratio & 0x3f) << 6; + RCBA32(SOFT_RESET_DATA) = soft_reset; + + /* Set soft reset control to use register value */ + RCBA32_OR(SOFT_RESET_CTRL, 1); + + /* Delay before reset to avoid potential TPM lockout */ + bootblock_mdelay(30); + + /* Issue warm reset, will be "CPU only" due to soft reset data */ + outb(0x0, 0xcf9); + outb(0x6, 0xcf9); + halt(); +} + +static void check_for_clean_reset(void) +{ + msr_t msr; + msr = rdmsr(MTRRdefType_MSR); + + /* Use the MTRR default type MSR as a proxy for detecting INIT#. + * Reset the system if any known bits are set in that MSR. That is + * an indication of the CPU not being properly reset. */ + if (msr.lo & (MTRRdefTypeEn | MTRRdefTypeFixEn)) { + outb(0x0, 0xcf9); + outb(0x6, 0xcf9); + halt(); + } +} + +static void bootblock_cpu_init(void) +{ + /* Set flex ratio and reset if needed */ + set_flex_ratio_to_tdp_nominal(); + check_for_clean_reset(); + enable_rom_caching(); + intel_update_microcode_from_cbfs(); +} |