diff options
| -rw-r--r-- | arch/arm/include/asm/efi.h | 7 | ||||
| -rw-r--r-- | drivers/firmware/efi/arm-init.c | 34 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/arm32-stub.c | 54 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efi-stub.c | 3 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efistub.h | 2 | ||||
| -rw-r--r-- | include/linux/efi.h | 1 |
6 files changed, 98 insertions, 3 deletions
diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h index 84dc0ba822f5..5dcf3c6011b7 100644 --- a/arch/arm/include/asm/efi.h +++ b/arch/arm/include/asm/efi.h @@ -87,4 +87,11 @@ static inline unsigned long efi_get_max_initrd_addr(unsigned long dram_base, return dram_base + SZ_512M; } +struct efi_arm_entry_state { + u32 cpsr_before_ebs; + u32 sctlr_before_ebs; + u32 cpsr_after_ebs; + u32 sctlr_after_ebs; +}; + #endif /* _ASM_ARM_EFI_H */ diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c index 6f4baf70db16..71c445d20258 100644 --- a/drivers/firmware/efi/arm-init.c +++ b/drivers/firmware/efi/arm-init.c @@ -52,9 +52,11 @@ static phys_addr_t __init efi_to_phys(unsigned long addr) } static __initdata unsigned long screen_info_table = EFI_INVALID_TABLE_ADDR; +static __initdata unsigned long cpu_state_table = EFI_INVALID_TABLE_ADDR; static const efi_config_table_type_t arch_tables[] __initconst = { {LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID, &screen_info_table}, + {LINUX_EFI_ARM_CPU_STATE_TABLE_GUID, &cpu_state_table}, {} }; @@ -240,9 +242,37 @@ void __init efi_init(void) init_screen_info(); +#ifdef CONFIG_ARM /* ARM does not permit early mappings to persist across paging_init() */ - if (IS_ENABLED(CONFIG_ARM)) - efi_memmap_unmap(); + efi_memmap_unmap(); + + if (cpu_state_table != EFI_INVALID_TABLE_ADDR) { + struct efi_arm_entry_state *state; + bool dump_state = true; + + state = early_memremap_ro(cpu_state_table, + sizeof(struct efi_arm_entry_state)); + if (state == NULL) { + pr_warn("Unable to map CPU entry state table.\n"); + return; + } + + if ((state->sctlr_before_ebs & 1) == 0) + pr_warn(FW_BUG "EFI stub was entered with MMU and Dcache disabled, please fix your firmware!\n"); + else if ((state->sctlr_after_ebs & 1) == 0) + pr_warn(FW_BUG "ExitBootServices() returned with MMU and Dcache disabled, please fix your firmware!\n"); + else + dump_state = false; + + if (dump_state || efi_enabled(EFI_DBG)) { + pr_info("CPSR at EFI stub entry : 0x%08x\n", state->cpsr_before_ebs); + pr_info("SCTLR at EFI stub entry : 0x%08x\n", state->sctlr_before_ebs); + pr_info("CPSR after ExitBootServices() : 0x%08x\n", state->cpsr_after_ebs); + pr_info("SCTLR after ExitBootServices(): 0x%08x\n", state->sctlr_after_ebs); + } + early_memunmap(state, sizeof(struct efi_arm_entry_state)); + } +#endif } static bool efifb_overlaps_pci_range(const struct of_pci_range *range) diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c index 40243f524556..d08e5d55838c 100644 --- a/drivers/firmware/efi/libstub/arm32-stub.c +++ b/drivers/firmware/efi/libstub/arm32-stub.c @@ -7,10 +7,49 @@ #include "efistub.h" +static efi_guid_t cpu_state_guid = LINUX_EFI_ARM_CPU_STATE_TABLE_GUID; + +struct efi_arm_entry_state *efi_entry_state; + +static void get_cpu_state(u32 *cpsr, u32 *sctlr) +{ + asm("mrs %0, cpsr" : "=r"(*cpsr)); + if ((*cpsr & MODE_MASK) == HYP_MODE) + asm("mrc p15, 4, %0, c1, c0, 0" : "=r"(*sctlr)); + else + asm("mrc p15, 0, %0, c1, c0, 0" : "=r"(*sctlr)); +} + efi_status_t check_platform_features(void) { + efi_status_t status; + u32 cpsr, sctlr; int block; + get_cpu_state(&cpsr, &sctlr); + + efi_info("Entering in %s mode with MMU %sabled\n", + ((cpsr & MODE_MASK) == HYP_MODE) ? "HYP" : "SVC", + (sctlr & 1) ? "en" : "dis"); + + status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, + sizeof(*efi_entry_state), + (void **)&efi_entry_state); + if (status != EFI_SUCCESS) { + efi_err("allocate_pool() failed\n"); + return status; + } + + efi_entry_state->cpsr_before_ebs = cpsr; + efi_entry_state->sctlr_before_ebs = sctlr; + + status = efi_bs_call(install_configuration_table, &cpu_state_guid, + efi_entry_state); + if (status != EFI_SUCCESS) { + efi_err("install_configuration_table() failed\n"); + goto free_state; + } + /* non-LPAE kernels can run anywhere */ if (!IS_ENABLED(CONFIG_ARM_LPAE)) return EFI_SUCCESS; @@ -19,9 +58,22 @@ efi_status_t check_platform_features(void) block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0); if (block < 5) { efi_err("This LPAE kernel is not supported by your CPU\n"); - return EFI_UNSUPPORTED; + status = EFI_UNSUPPORTED; + goto drop_table; } return EFI_SUCCESS; + +drop_table: + efi_bs_call(install_configuration_table, &cpu_state_guid, NULL); +free_state: + efi_bs_call(free_pool, efi_entry_state); + return status; +} + +void efi_handle_post_ebs_state(void) +{ + get_cpu_state(&efi_entry_state->cpsr_after_ebs, + &efi_entry_state->sctlr_after_ebs); } static efi_guid_t screen_info_guid = LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID; diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c index e97370bdfdb0..3318ec3f8e5b 100644 --- a/drivers/firmware/efi/libstub/efi-stub.c +++ b/drivers/firmware/efi/libstub/efi-stub.c @@ -329,6 +329,9 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, if (status != EFI_SUCCESS) goto fail_free_initrd; + if (IS_ENABLED(CONFIG_ARM)) + efi_handle_post_ebs_state(); + efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr)); /* not reached */ diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index ac756f1fdb1a..2c9d42264c29 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -777,4 +777,6 @@ efi_status_t efi_load_initrd(efi_loaded_image_t *image, unsigned long soft_limit, unsigned long hard_limit); +void efi_handle_post_ebs_state(void); + #endif diff --git a/include/linux/efi.h b/include/linux/efi.h index c3449c9699d0..bb35f3305e55 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -350,6 +350,7 @@ void efi_native_runtime_setup(void); * associated with ConOut */ #define LINUX_EFI_ARM_SCREEN_INFO_TABLE_GUID EFI_GUID(0xe03fc20a, 0x85dc, 0x406e, 0xb9, 0x0e, 0x4a, 0xb5, 0x02, 0x37, 0x1d, 0x95) +#define LINUX_EFI_ARM_CPU_STATE_TABLE_GUID EFI_GUID(0xef79e4aa, 0x3c3d, 0x4989, 0xb9, 0x02, 0x07, 0xa9, 0x43, 0xe5, 0x50, 0xd2) #define LINUX_EFI_LOADER_ENTRY_GUID EFI_GUID(0x4a67b082, 0x0a4c, 0x41cf, 0xb6, 0xc7, 0x44, 0x0b, 0x29, 0xbb, 0x8c, 0x4f) #define LINUX_EFI_RANDOM_SEED_TABLE_GUID EFI_GUID(0x1ce1e5bc, 0x7ceb, 0x42f2, 0x81, 0xe5, 0x8a, 0xad, 0xf1, 0x80, 0xf5, 0x7b) #define LINUX_EFI_TPM_EVENT_LOG_GUID EFI_GUID(0xb7799cb0, 0xeca2, 0x4943, 0x96, 0x67, 0x1f, 0xae, 0x07, 0xb7, 0x47, 0xfa) |