diff options
Diffstat (limited to 'src/soc/intel/elkhartlake/smmrelocate.c')
| -rw-r--r-- | src/soc/intel/elkhartlake/smmrelocate.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/src/soc/intel/elkhartlake/smmrelocate.c b/src/soc/intel/elkhartlake/smmrelocate.c new file mode 100644 index 0000000000..11b631bb86 --- /dev/null +++ b/src/soc/intel/elkhartlake/smmrelocate.c @@ -0,0 +1,234 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include <console/console.h> +#include <cpu/intel/em64t101_save_state.h> +#include <cpu/intel/smm_reloc.h> +#include <cpu/x86/mp.h> +#include <cpu/x86/msr.h> +#include <cpu/x86/mtrr.h> +#include <cpu/x86/smm.h> +#include <device/device.h> +#include <device/pci.h> +#include <device/pci_ops.h> +#include <smp/node.h> +#include <soc/cpu.h> +#include <soc/msr.h> +#include <soc/pci_devs.h> +#include <soc/soc_chip.h> +#include <string.h> +#include <types.h> + +static void update_save_state(int cpu, uintptr_t curr_smbase, + uintptr_t staggered_smbase, + struct smm_relocation_params *relo_params) +{ + u32 smbase; + u32 iedbase; + + /* + * The relocated handler runs with all CPUs concurrently. Therefore + * stagger the entry points adjusting SMBASE downwards by save state + * size * CPU num. + */ + smbase = staggered_smbase; + iedbase = relo_params->ied_base; + + printk(BIOS_DEBUG, "New SMBASE=0x%08x IEDBASE=0x%08x\n", + smbase, iedbase); + + /* + * All threads need to set IEDBASE and SMBASE to the relocated + * handler region. However, the save state location depends on the + * smm_save_state_in_msrs field in the relocation parameters. If + * smm_save_state_in_msrs is non-zero then the CPUs are relocating + * the SMM handler in parallel, and each CPUs save state area is + * located in their respective MSR space. If smm_save_state_in_msrs + * is zero then the SMM relocation is happening serially so the + * save state is at the same default location for all CPUs. + */ + if (relo_params->smm_save_state_in_msrs) { + msr_t smbase_msr; + msr_t iedbase_msr; + + smbase_msr.lo = smbase; + smbase_msr.hi = 0; + + /* + * According the BWG the IEDBASE MSR is in bits 63:32. It's + * not clear why it differs from the SMBASE MSR. + */ + iedbase_msr.lo = 0; + iedbase_msr.hi = iedbase; + + wrmsr(SMBASE_MSR, smbase_msr); + wrmsr(IEDBASE_MSR, iedbase_msr); + } else { + em64t101_smm_state_save_area_t *save_state; + + save_state = (void *)(curr_smbase + SMM_DEFAULT_SIZE - + sizeof(*save_state)); + + save_state->smbase = smbase; + save_state->iedbase = iedbase; + } +} + +/* Returns 1 if SMM MSR save state was set. */ +static int bsp_setup_msr_save_state(struct smm_relocation_params *relo_params) +{ + msr_t smm_mca_cap; + + smm_mca_cap = rdmsr(SMM_MCA_CAP_MSR); + if (smm_mca_cap.hi & SMM_CPU_SVRSTR_MASK) { + msr_t smm_feature_control; + + smm_feature_control = rdmsr(SMM_FEATURE_CONTROL_MSR); + smm_feature_control.hi = 0; + smm_feature_control.lo |= SMM_CPU_SAVE_EN; + wrmsr(SMM_FEATURE_CONTROL_MSR, smm_feature_control); + relo_params->smm_save_state_in_msrs = 1; + } + return relo_params->smm_save_state_in_msrs; +} + +/* + * The relocation work is actually performed in SMM context, but the code + * resides in the ramstage module. This occurs by trampolining from the default + * SMRAM entry point to here. + */ +void smm_relocation_handler(int cpu, uintptr_t curr_smbase, + uintptr_t staggered_smbase) +{ + msr_t mtrr_cap; + struct smm_relocation_params *relo_params = &smm_reloc_params; + + printk(BIOS_DEBUG, "In relocation handler: CPU %d\n", cpu); + + /* + * Determine if the processor supports saving state in MSRs. If so, + * enable it before the non-BSPs run so that SMM relocation can occur + * in parallel in the non-BSP CPUs. + */ + if (cpu == 0) { + /* + * If smm_save_state_in_msrs is 1 then that means this is the + * 2nd time through the relocation handler for the BSP. + * Parallel SMM handler relocation is taking place. However, + * it is desired to access other CPUs save state in the real + * SMM handler. Therefore, disable the SMM save state in MSRs + * feature. + */ + if (relo_params->smm_save_state_in_msrs) { + msr_t smm_feature_control; + + smm_feature_control = rdmsr(SMM_FEATURE_CONTROL_MSR); + smm_feature_control.lo &= ~SMM_CPU_SAVE_EN; + wrmsr(SMM_FEATURE_CONTROL_MSR, smm_feature_control); + } else if (bsp_setup_msr_save_state(relo_params)) + /* + * Just return from relocation handler if MSR save + * state is enabled. In that case the BSP will come + * back into the relocation handler to setup the new + * SMBASE as well disabling SMM save state in MSRs. + */ + return; + } + + /* Make appropriate changes to the save state map. */ + update_save_state(cpu, curr_smbase, staggered_smbase, relo_params); + + /* Write SMRR MSRs based on indicated support. */ + mtrr_cap = rdmsr(MTRR_CAP_MSR); + if (mtrr_cap.lo & SMRR_SUPPORTED) + write_smrr(relo_params); +} + +static void fill_in_relocation_params(struct smm_relocation_params *params) +{ + uintptr_t tseg_base; + size_t tseg_size; + /* All range registers are aligned to 4KiB */ + const u32 rmask = ~(4 * KiB - 1); + + smm_region(&tseg_base, &tseg_size); + + if (!IS_ALIGNED(tseg_base, tseg_size)) { + printk(BIOS_WARNING, + "TSEG base not aligned with TSEG SIZE! Not setting SMRR\n"); + return; + } + + smm_subregion(SMM_SUBREGION_CHIPSET, ¶ms->ied_base, ¶ms->ied_size); + + /* SMRR has 32-bits of valid address aligned to 4KiB. */ + params->smrr_base.lo = (tseg_base & rmask) | MTRR_TYPE_WRBACK; + params->smrr_base.hi = 0; + params->smrr_mask.lo = (~(tseg_size - 1) & rmask) | MTRR_PHYS_MASK_VALID; + params->smrr_mask.hi = 0; +} + +static void setup_ied_area(struct smm_relocation_params *params) +{ + char *ied_base; + + struct ied_header ied = { + .signature = "INTEL RSVD", + .size = params->ied_size, + .reserved = {0}, + }; + + ied_base = (void *)params->ied_base; + + printk(BIOS_DEBUG, "IED base = 0x%08x\n", (u32)params->ied_base); + printk(BIOS_DEBUG, "IED size = 0x%08x\n", (u32)params->ied_size); + + /* Place IED header at IEDBASE. */ + memcpy(ied_base, &ied, sizeof(ied)); + + /* Zero out 32KiB at IEDBASE + 1MiB */ + memset(ied_base + 1 * MiB, 0, 32 * KiB); +} + +void smm_info(uintptr_t *perm_smbase, size_t *perm_smsize, + size_t *smm_save_state_size) +{ + printk(BIOS_DEBUG, "Setting up SMI for CPU\n"); + + fill_in_relocation_params(&smm_reloc_params); + + smm_subregion(SMM_SUBREGION_HANDLER, perm_smbase, perm_smsize); + + if (smm_reloc_params.ied_size) + setup_ied_area(&smm_reloc_params); + + *smm_save_state_size = sizeof(em64t101_smm_state_save_area_t); +} + +void smm_initialize(void) +{ + /* Clear the SMM state in the southbridge. */ + smm_southbridge_clear_state(); + + /* + * Run the relocation handler for on the BSP to check and set up + * parallel SMM relocation. + */ + smm_initiate_relocation(); + + if (smm_reloc_params.smm_save_state_in_msrs) + printk(BIOS_DEBUG, "Doing parallel SMM relocation.\n"); +} + +void smm_relocate(void) +{ + /* + * If smm_save_state_in_msrs is non-zero then parallel SMM relocation + * shall take place. Run the relocation handler a second time on the + * BSP to do * the final move. For APs, a relocation handler always + * needs to be run. + */ + if (smm_reloc_params.smm_save_state_in_msrs) + smm_initiate_relocation_parallel(); + else if (!boot_cpu()) + smm_initiate_relocation(); +} |