From e5bc22a42e4d46cc203fdfb6d2c76202b08666a0 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 30 Nov 2015 13:28:18 +0100 Subject: arm64/efi: split off EFI init and runtime code for reuse by 32-bit ARM This splits off the early EFI init and runtime code that - discovers the EFI params and the memory map from the FDT, and installs the memblocks and config tables. - prepares and installs the EFI page tables so that UEFI Runtime Services can be invoked at the virtual address installed by the stub. This will allow it to be reused for 32-bit ARM. Reviewed-by: Matt Fleming Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon --- drivers/firmware/efi/Makefile | 3 + drivers/firmware/efi/arm-init.c | 208 +++++++++++++++++++++++++++++++++++++ drivers/firmware/efi/arm-runtime.c | 151 +++++++++++++++++++++++++++ 3 files changed, 362 insertions(+) create mode 100644 drivers/firmware/efi/arm-init.c create mode 100644 drivers/firmware/efi/arm-runtime.c (limited to 'drivers') diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index ec379a4164cc..f292917b00e7 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -18,3 +18,6 @@ obj-$(CONFIG_EFI_RUNTIME_MAP) += runtime-map.o obj-$(CONFIG_EFI_RUNTIME_WRAPPERS) += runtime-wrappers.o obj-$(CONFIG_EFI_STUB) += libstub/ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o + +arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o +obj-$(CONFIG_ARM64) += $(arm-obj-y) diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c new file mode 100644 index 000000000000..ffdd76a51929 --- /dev/null +++ b/drivers/firmware/efi/arm-init.c @@ -0,0 +1,208 @@ +/* + * Extensible Firmware Interface + * + * Based on Extensible Firmware Interface Specification version 2.4 + * + * Copyright (C) 2013 - 2015 Linaro Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include + +#include + +struct efi_memory_map memmap; + +u64 efi_system_table; + +static int __init is_normal_ram(efi_memory_desc_t *md) +{ + if (md->attribute & EFI_MEMORY_WB) + return 1; + return 0; +} + +/* + * Translate a EFI virtual address into a physical address: this is necessary, + * as some data members of the EFI system table are virtually remapped after + * SetVirtualAddressMap() has been called. + */ +static phys_addr_t efi_to_phys(unsigned long addr) +{ + efi_memory_desc_t *md; + + for_each_efi_memory_desc(&memmap, md) { + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == 0) + /* no virtual mapping has been installed by the stub */ + break; + if (md->virt_addr <= addr && + (addr - md->virt_addr) < (md->num_pages << EFI_PAGE_SHIFT)) + return md->phys_addr + addr - md->virt_addr; + } + return addr; +} + +static int __init uefi_init(void) +{ + efi_char16_t *c16; + void *config_tables; + u64 table_size; + char vendor[100] = "unknown"; + int i, retval; + + efi.systab = early_memremap(efi_system_table, + sizeof(efi_system_table_t)); + if (efi.systab == NULL) { + pr_warn("Unable to map EFI system table.\n"); + return -ENOMEM; + } + + set_bit(EFI_BOOT, &efi.flags); + set_bit(EFI_64BIT, &efi.flags); + + /* + * Verify the EFI Table + */ + if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) { + pr_err("System table signature incorrect\n"); + retval = -EINVAL; + goto out; + } + if ((efi.systab->hdr.revision >> 16) < 2) + pr_warn("Warning: EFI system table version %d.%02d, expected 2.00 or greater\n", + efi.systab->hdr.revision >> 16, + efi.systab->hdr.revision & 0xffff); + + /* Show what we know for posterity */ + c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor), + sizeof(vendor) * sizeof(efi_char16_t)); + if (c16) { + for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i) + vendor[i] = c16[i]; + vendor[i] = '\0'; + early_memunmap(c16, sizeof(vendor) * sizeof(efi_char16_t)); + } + + pr_info("EFI v%u.%.02u by %s\n", + efi.systab->hdr.revision >> 16, + efi.systab->hdr.revision & 0xffff, vendor); + + table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables; + config_tables = early_memremap(efi_to_phys(efi.systab->tables), + table_size); + if (config_tables == NULL) { + pr_warn("Unable to map EFI config table array.\n"); + retval = -ENOMEM; + goto out; + } + retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, + sizeof(efi_config_table_64_t), NULL); + + early_memunmap(config_tables, table_size); +out: + early_memunmap(efi.systab, sizeof(efi_system_table_t)); + return retval; +} + +/* + * Return true for RAM regions we want to permanently reserve. + */ +static __init int is_reserve_region(efi_memory_desc_t *md) +{ + switch (md->type) { + case EFI_LOADER_CODE: + case EFI_LOADER_DATA: + case EFI_BOOT_SERVICES_CODE: + case EFI_BOOT_SERVICES_DATA: + case EFI_CONVENTIONAL_MEMORY: + case EFI_PERSISTENT_MEMORY: + return 0; + default: + break; + } + return is_normal_ram(md); +} + +static __init void reserve_regions(void) +{ + efi_memory_desc_t *md; + u64 paddr, npages, size; + + if (efi_enabled(EFI_DBG)) + pr_info("Processing EFI memory map:\n"); + + for_each_efi_memory_desc(&memmap, md) { + paddr = md->phys_addr; + npages = md->num_pages; + + if (efi_enabled(EFI_DBG)) { + char buf[64]; + + pr_info(" 0x%012llx-0x%012llx %s", + paddr, paddr + (npages << EFI_PAGE_SHIFT) - 1, + efi_md_typeattr_format(buf, sizeof(buf), md)); + } + + memrange_efi_to_native(&paddr, &npages); + size = npages << PAGE_SHIFT; + + if (is_normal_ram(md)) + early_init_dt_add_memory_arch(paddr, size); + + if (is_reserve_region(md)) { + memblock_mark_nomap(paddr, size); + if (efi_enabled(EFI_DBG)) + pr_cont("*"); + } + + if (efi_enabled(EFI_DBG)) + pr_cont("\n"); + } + + set_bit(EFI_MEMMAP, &efi.flags); +} + +void __init efi_init(void) +{ + struct efi_fdt_params params; + + /* Grab UEFI information placed in FDT by stub */ + if (!efi_get_fdt_params(¶ms)) + return; + + efi_system_table = params.system_table; + + memmap.phys_map = params.mmap; + memmap.map = early_memremap(params.mmap, params.mmap_size); + if (memmap.map == NULL) { + /* + * If we are booting via UEFI, the UEFI memory map is the only + * description of memory we have, so there is little point in + * proceeding if we cannot access it. + */ + panic("Unable to map EFI memory map.\n"); + } + memmap.map_end = memmap.map + params.mmap_size; + memmap.desc_size = params.desc_size; + memmap.desc_version = params.desc_ver; + + if (uefi_init() < 0) + return; + + reserve_regions(); + early_memunmap(memmap.map, params.mmap_size); + memblock_mark_nomap(params.mmap & PAGE_MASK, + PAGE_ALIGN(params.mmap_size + + (params.mmap & ~PAGE_MASK))); +} diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c new file mode 100644 index 000000000000..974743e13a4d --- /dev/null +++ b/drivers/firmware/efi/arm-runtime.c @@ -0,0 +1,151 @@ +/* + * Extensible Firmware Interface + * + * Based on Extensible Firmware Interface Specification version 2.4 + * + * Copyright (C) 2013, 2014 Linaro Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; + +extern u64 efi_system_table; + +static struct mm_struct efi_mm = { + .mm_rb = RB_ROOT, + .pgd = efi_pgd, + .mm_users = ATOMIC_INIT(2), + .mm_count = ATOMIC_INIT(1), + .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), + .page_table_lock = __SPIN_LOCK_UNLOCKED(efi_mm.page_table_lock), + .mmlist = LIST_HEAD_INIT(efi_mm.mmlist), +}; + +static bool __init efi_virtmap_init(void) +{ + efi_memory_desc_t *md; + + init_new_context(NULL, &efi_mm); + + for_each_efi_memory_desc(&memmap, md) { + pgprot_t prot; + + if (!(md->attribute & EFI_MEMORY_RUNTIME)) + continue; + if (md->virt_addr == 0) + return false; + + pr_info(" EFI remap 0x%016llx => %p\n", + md->phys_addr, (void *)md->virt_addr); + + /* + * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be + * executable, everything else can be mapped with the XN bits + * set. + */ + if ((md->attribute & EFI_MEMORY_WB) == 0) + prot = __pgprot(PROT_DEVICE_nGnRE); + else if (md->type == EFI_RUNTIME_SERVICES_CODE || + !PAGE_ALIGNED(md->phys_addr)) + prot = PAGE_KERNEL_EXEC; + else + prot = PAGE_KERNEL; + + create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr, + md->num_pages << EFI_PAGE_SHIFT, + __pgprot(pgprot_val(prot) | PTE_NG)); + } + return true; +} + +/* + * Enable the UEFI Runtime Services if all prerequisites are in place, i.e., + * non-early mapping of the UEFI system table and virtual mappings for all + * EFI_MEMORY_RUNTIME regions. + */ +static int __init arm64_enable_runtime_services(void) +{ + u64 mapsize; + + if (!efi_enabled(EFI_BOOT)) { + pr_info("EFI services will not be available.\n"); + return 0; + } + + if (efi_runtime_disabled()) { + pr_info("EFI runtime services will be disabled.\n"); + return 0; + } + + pr_info("Remapping and enabling EFI services.\n"); + + mapsize = memmap.map_end - memmap.map; + memmap.map = (__force void *)ioremap_cache(memmap.phys_map, + mapsize); + if (!memmap.map) { + pr_err("Failed to remap EFI memory map\n"); + return -ENOMEM; + } + memmap.map_end = memmap.map + mapsize; + efi.memmap = &memmap; + + efi.systab = (__force void *)ioremap_cache(efi_system_table, + sizeof(efi_system_table_t)); + if (!efi.systab) { + pr_err("Failed to remap EFI System Table\n"); + return -ENOMEM; + } + set_bit(EFI_SYSTEM_TABLES, &efi.flags); + + if (!efi_virtmap_init()) { + pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n"); + return -ENOMEM; + } + + /* Set up runtime services function pointers */ + efi_native_runtime_setup(); + set_bit(EFI_RUNTIME_SERVICES, &efi.flags); + + efi.runtime_version = efi.systab->hdr.revision; + + return 0; +} +early_initcall(arm64_enable_runtime_services); + +static void efi_set_pgd(struct mm_struct *mm) +{ + switch_mm(NULL, mm, NULL); +} + +void efi_virtmap_load(void) +{ + preempt_disable(); + efi_set_pgd(&efi_mm); +} + +void efi_virtmap_unload(void) +{ + efi_set_pgd(current->active_mm); + preempt_enable(); +} -- cgit v1.2.3 From f7d924894265794f447ea799dd853400749b5a22 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 30 Nov 2015 13:28:19 +0100 Subject: arm64/efi: refactor EFI init and runtime code for reuse by 32-bit ARM This refactors the EFI init and runtime code that will be shared between arm64 and ARM so that it can be built for both archs. Reviewed-by: Matt Fleming Signed-off-by: Ard Biesheuvel Signed-off-by: Will Deacon --- arch/arm64/include/asm/efi.h | 9 +++++++ arch/arm64/kernel/efi.c | 23 ++++++++++++++++++ drivers/firmware/efi/arm-init.c | 7 +++--- drivers/firmware/efi/arm-runtime.c | 48 +++++++++++++------------------------- drivers/firmware/efi/efi.c | 2 ++ 5 files changed, 54 insertions(+), 35 deletions(-) (limited to 'drivers') diff --git a/arch/arm64/include/asm/efi.h b/arch/arm64/include/asm/efi.h index ef572206f1c3..8e88a696c9cb 100644 --- a/arch/arm64/include/asm/efi.h +++ b/arch/arm64/include/asm/efi.h @@ -2,7 +2,9 @@ #define _ASM_EFI_H #include +#include #include +#include #ifdef CONFIG_EFI extern void efi_init(void); @@ -10,6 +12,8 @@ extern void efi_init(void); #define efi_init() #endif +int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md); + #define efi_call_virt(f, ...) \ ({ \ efi_##f##_t *__f; \ @@ -63,6 +67,11 @@ extern void efi_init(void); * Services are enabled and the EFI_RUNTIME_SERVICES bit set. */ +static inline void efi_set_pgd(struct mm_struct *mm) +{ + switch_mm(NULL, mm, NULL); +} + void efi_virtmap_load(void); void efi_virtmap_unload(void); diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index bd3b2f5adf0c..b6abc852f2a1 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -17,6 +17,29 @@ #include +int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) +{ + pteval_t prot_val; + + /* + * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be + * executable, everything else can be mapped with the XN bits + * set. + */ + if ((md->attribute & EFI_MEMORY_WB) == 0) + prot_val = PROT_DEVICE_nGnRE; + else if (md->type == EFI_RUNTIME_SERVICES_CODE || + !PAGE_ALIGNED(md->phys_addr)) + prot_val = pgprot_val(PAGE_KERNEL_EXEC); + else + prot_val = pgprot_val(PAGE_KERNEL); + + create_pgd_mapping(mm, md->phys_addr, md->virt_addr, + md->num_pages << EFI_PAGE_SHIFT, + __pgprot(prot_val | PTE_NG)); + return 0; +} + static int __init arm64_dmi_init(void) { /* diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c index ffdd76a51929..9e15d571b53c 100644 --- a/drivers/firmware/efi/arm-init.c +++ b/drivers/firmware/efi/arm-init.c @@ -57,7 +57,7 @@ static int __init uefi_init(void) { efi_char16_t *c16; void *config_tables; - u64 table_size; + size_t table_size; char vendor[100] = "unknown"; int i, retval; @@ -69,7 +69,8 @@ static int __init uefi_init(void) } set_bit(EFI_BOOT, &efi.flags); - set_bit(EFI_64BIT, &efi.flags); + if (IS_ENABLED(CONFIG_64BIT)) + set_bit(EFI_64BIT, &efi.flags); /* * Verify the EFI Table @@ -107,7 +108,7 @@ static int __init uefi_init(void) goto out; } retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, - sizeof(efi_config_table_64_t), NULL); + sizeof(efi_config_table_t), NULL); early_memunmap(config_tables, table_size); out: diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c index 974743e13a4d..6ae21e41a429 100644 --- a/drivers/firmware/efi/arm-runtime.c +++ b/drivers/firmware/efi/arm-runtime.c @@ -12,6 +12,7 @@ */ #include +#include #include #include #include @@ -23,18 +24,14 @@ #include #include -#include -#include #include +#include #include -static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss; - extern u64 efi_system_table; static struct mm_struct efi_mm = { .mm_rb = RB_ROOT, - .pgd = efi_pgd, .mm_users = ATOMIC_INIT(2), .mm_count = ATOMIC_INIT(1), .mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem), @@ -46,35 +43,27 @@ static bool __init efi_virtmap_init(void) { efi_memory_desc_t *md; + efi_mm.pgd = pgd_alloc(&efi_mm); init_new_context(NULL, &efi_mm); for_each_efi_memory_desc(&memmap, md) { - pgprot_t prot; + phys_addr_t phys = md->phys_addr; + int ret; if (!(md->attribute & EFI_MEMORY_RUNTIME)) continue; if (md->virt_addr == 0) return false; - pr_info(" EFI remap 0x%016llx => %p\n", - md->phys_addr, (void *)md->virt_addr); - - /* - * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be - * executable, everything else can be mapped with the XN bits - * set. - */ - if ((md->attribute & EFI_MEMORY_WB) == 0) - prot = __pgprot(PROT_DEVICE_nGnRE); - else if (md->type == EFI_RUNTIME_SERVICES_CODE || - !PAGE_ALIGNED(md->phys_addr)) - prot = PAGE_KERNEL_EXEC; - else - prot = PAGE_KERNEL; - - create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr, - md->num_pages << EFI_PAGE_SHIFT, - __pgprot(pgprot_val(prot) | PTE_NG)); + ret = efi_create_mapping(&efi_mm, md); + if (!ret) { + pr_info(" EFI remap %pa => %p\n", + &phys, (void *)(unsigned long)md->virt_addr); + } else { + pr_warn(" EFI remap %pa: failed to create mapping (%d)\n", + &phys, ret); + return false; + } } return true; } @@ -84,7 +73,7 @@ static bool __init efi_virtmap_init(void) * non-early mapping of the UEFI system table and virtual mappings for all * EFI_MEMORY_RUNTIME regions. */ -static int __init arm64_enable_runtime_services(void) +static int __init arm_enable_runtime_services(void) { u64 mapsize; @@ -131,12 +120,7 @@ static int __init arm64_enable_runtime_services(void) return 0; } -early_initcall(arm64_enable_runtime_services); - -static void efi_set_pgd(struct mm_struct *mm) -{ - switch_mm(NULL, mm, NULL); -} +early_initcall(arm_enable_runtime_services); void efi_virtmap_load(void) { diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 027ca212179f..cffa89b3317b 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -25,6 +25,8 @@ #include #include +#include + struct efi __read_mostly efi = { .mps = EFI_INVALID_TABLE_ADDR, .acpi = EFI_INVALID_TABLE_ADDR, -- cgit v1.2.3 From da58fb6571bf40e5b2287d6aa3bbca04965f5677 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 24 Sep 2015 13:49:52 -0700 Subject: ARM: wire up UEFI init and runtime support This adds support to the kernel proper for booting via UEFI. It shares most of the code with arm64, so this patch mostly just wires it up for use with ARM. Note that this does not include the EFI stub, it is added in a subsequent patch. Tested-by: Ryan Harkin Reviewed-by: Matt Fleming Signed-off-by: Ard Biesheuvel --- arch/arm/include/asm/efi.h | 60 ++++++++++++++++++++++++++++++++++++++ arch/arm/include/asm/mmu_context.h | 2 +- arch/arm/kernel/Makefile | 1 + arch/arm/kernel/efi.c | 38 ++++++++++++++++++++++++ arch/arm/kernel/setup.c | 3 ++ drivers/firmware/efi/Makefile | 1 + 6 files changed, 104 insertions(+), 1 deletion(-) create mode 100644 arch/arm/include/asm/efi.h create mode 100644 arch/arm/kernel/efi.c (limited to 'drivers') diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h new file mode 100644 index 000000000000..c91e330616ad --- /dev/null +++ b/arch/arm/include/asm/efi.h @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2015 Linaro Ltd + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#ifndef __ASM_ARM_EFI_H +#define __ASM_ARM_EFI_H + +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_EFI +void efi_init(void); + +int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md); + +#define efi_call_virt(f, ...) \ +({ \ + efi_##f##_t *__f; \ + efi_status_t __s; \ + \ + efi_virtmap_load(); \ + __f = efi.systab->runtime->f; \ + __s = __f(__VA_ARGS__); \ + efi_virtmap_unload(); \ + __s; \ +}) + +#define __efi_call_virt(f, ...) \ +({ \ + efi_##f##_t *__f; \ + \ + efi_virtmap_load(); \ + __f = efi.systab->runtime->f; \ + __f(__VA_ARGS__); \ + efi_virtmap_unload(); \ +}) + +static inline void efi_set_pgd(struct mm_struct *mm) +{ + check_and_switch_context(mm, NULL); +} + +void efi_virtmap_load(void); +void efi_virtmap_unload(void); + +#else +#define efi_init() +#endif /* CONFIG_EFI */ + +#endif /* _ASM_ARM_EFI_H */ diff --git a/arch/arm/include/asm/mmu_context.h b/arch/arm/include/asm/mmu_context.h index 9b32f76bb0dd..432ce8176498 100644 --- a/arch/arm/include/asm/mmu_context.h +++ b/arch/arm/include/asm/mmu_context.h @@ -26,7 +26,7 @@ void __check_vmalloc_seq(struct mm_struct *mm); #ifdef CONFIG_CPU_HAS_ASID void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk); -#define init_new_context(tsk,mm) ({ atomic64_set(&mm->context.id, 0); 0; }) +#define init_new_context(tsk,mm) ({ atomic64_set(&(mm)->context.id, 0); 0; }) #ifdef CONFIG_ARM_ERRATA_798181 void a15_erratum_get_cpumask(int this_cpu, struct mm_struct *mm, diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index af9e59bf3831..c90f4a70d646 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -77,6 +77,7 @@ CFLAGS_pj4-cp0.o := -marm AFLAGS_iwmmxt.o := -Wa,-mcpu=iwmmxt obj-$(CONFIG_ARM_CPU_TOPOLOGY) += topology.o obj-$(CONFIG_VDSO) += vdso.o +obj-$(CONFIG_EFI) += efi.o ifneq ($(CONFIG_ARCH_EBSA110),y) obj-y += io.o diff --git a/arch/arm/kernel/efi.c b/arch/arm/kernel/efi.c new file mode 100644 index 000000000000..ff8a9d8acfac --- /dev/null +++ b/arch/arm/kernel/efi.c @@ -0,0 +1,38 @@ +/* + * Copyright (C) 2015 Linaro Ltd + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include + +int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) +{ + struct map_desc desc = { + .virtual = md->virt_addr, + .pfn = __phys_to_pfn(md->phys_addr), + .length = md->num_pages * EFI_PAGE_SIZE, + }; + + /* + * Order is important here: memory regions may have all of the + * bits below set (and usually do), so we check them in order of + * preference. + */ + if (md->attribute & EFI_MEMORY_WB) + desc.type = MT_MEMORY_RWX; + else if (md->attribute & EFI_MEMORY_WT) + desc.type = MT_MEMORY_RWX_NONCACHED; + else if (md->attribute & EFI_MEMORY_WC) + desc.type = MT_DEVICE_WC; + else + desc.type = MT_DEVICE; + + create_mapping_late(mm, &desc, true); + return 0; +} diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 5df2bca57c42..b341b1c3b2fa 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -7,6 +7,7 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ +#include #include #include #include @@ -37,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -966,6 +968,7 @@ void __init setup_arch(char **cmdline_p) early_paging_init(mdesc); #endif setup_dma_zone(mdesc); + efi_init(); sanity_check_meminfo(); arm_memblock_init(mdesc); diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index f292917b00e7..62e654f255f4 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -20,4 +20,5 @@ obj-$(CONFIG_EFI_STUB) += libstub/ obj-$(CONFIG_EFI_FAKE_MEMMAP) += fake_mem.o arm-obj-$(CONFIG_EFI) := arm-init.o arm-runtime.o +obj-$(CONFIG_ARM) += $(arm-obj-y) obj-$(CONFIG_ARM64) += $(arm-obj-y) -- cgit v1.2.3 From 81a0bc39ea1960bbf8ece6a895d7cfd2d9efa28a Mon Sep 17 00:00:00 2001 From: Roy Franz Date: Wed, 23 Sep 2015 20:17:54 -0700 Subject: ARM: add UEFI stub support This patch adds EFI stub support for the ARM Linux kernel. The EFI stub operates similarly to the x86 and arm64 stubs: it is a shim between the EFI firmware and the normal zImage entry point, and sets up the environment that the zImage is expecting. This includes optionally loading the initrd and device tree from the system partition based on the kernel command line. Signed-off-by: Roy Franz Tested-by: Ryan Harkin Reviewed-by: Matt Fleming Signed-off-by: Ard Biesheuvel --- arch/arm/Kconfig | 19 +++++ arch/arm/boot/compressed/Makefile | 4 +- arch/arm/boot/compressed/efi-header.S | 130 ++++++++++++++++++++++++++++++ arch/arm/boot/compressed/head.S | 54 ++++++++++++- arch/arm/boot/compressed/vmlinux.lds.S | 7 ++ arch/arm/include/asm/efi.h | 23 ++++++ drivers/firmware/efi/libstub/Makefile | 9 +++ drivers/firmware/efi/libstub/arm-stub.c | 4 +- drivers/firmware/efi/libstub/arm32-stub.c | 85 +++++++++++++++++++ 9 files changed, 331 insertions(+), 4 deletions(-) create mode 100644 arch/arm/boot/compressed/efi-header.S create mode 100644 drivers/firmware/efi/libstub/arm32-stub.c (limited to 'drivers') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 446e49b56e6a..67f8303d513d 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -2041,6 +2041,25 @@ config AUTO_ZRELADDR 0xf8000000. This assumes the zImage being placed in the first 128MB from start of memory. +config EFI_STUB + bool + +config EFI + bool "UEFI runtime support" + depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL + select UCS2_STRING + select EFI_PARAMS_FROM_FDT + select EFI_STUB + select EFI_ARMSTUB + select EFI_RUNTIME_WRAPPERS + ---help--- + This option provides support for runtime services provided + by UEFI firmware (such as non-volatile variables, realtime + clock, and platform reset). A UEFI stub is also provided to + allow the kernel to be booted as an EFI application. This + is only useful for kernels that may run on systems that have + UEFI firmware. + endmenu menu "CPU Power Management" diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 3f9a9ebc77c3..4c23a68a0917 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -167,9 +167,11 @@ if [ $(words $(ZRELADDR)) -gt 1 -a "$(CONFIG_AUTO_ZRELADDR)" = "" ]; then \ false; \ fi +efi-obj-$(CONFIG_EFI_STUB) := $(objtree)/drivers/firmware/efi/libstub/lib.a + $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) \ - $(bswapsdi2) FORCE + $(bswapsdi2) $(efi-obj-y) FORCE @$(check_for_multiple_zreladdr) $(call if_changed,ld) @$(check_for_bad_syms) diff --git a/arch/arm/boot/compressed/efi-header.S b/arch/arm/boot/compressed/efi-header.S new file mode 100644 index 000000000000..9d5dc4fda3c1 --- /dev/null +++ b/arch/arm/boot/compressed/efi-header.S @@ -0,0 +1,130 @@ +/* + * Copyright (C) 2013-2015 Linaro Ltd + * Authors: Roy Franz + * Ard Biesheuvel + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + + .macro __nop +#ifdef CONFIG_EFI_STUB + @ This is almost but not quite a NOP, since it does clobber the + @ condition flags. But it is the best we can do for EFI, since + @ PE/COFF expects the magic string "MZ" at offset 0, while the + @ ARM/Linux boot protocol expects an executable instruction + @ there. + .inst 'M' | ('Z' << 8) | (0x1310 << 16) @ tstne r0, #0x4d000 +#else + mov r0, r0 +#endif + .endm + + .macro __EFI_HEADER +#ifdef CONFIG_EFI_STUB + b __efi_start + + .set start_offset, __efi_start - start + .org start + 0x3c + @ + @ The PE header can be anywhere in the file, but for + @ simplicity we keep it together with the MSDOS header + @ The offset to the PE/COFF header needs to be at offset + @ 0x3C in the MSDOS header. + @ The only 2 fields of the MSDOS header that are used are this + @ PE/COFF offset, and the "MZ" bytes at offset 0x0. + @ + .long pe_header - start @ Offset to the PE header. + +pe_header: + .ascii "PE\0\0" + +coff_header: + .short 0x01c2 @ ARM or Thumb + .short 2 @ nr_sections + .long 0 @ TimeDateStamp + .long 0 @ PointerToSymbolTable + .long 1 @ NumberOfSymbols + .short section_table - optional_header + @ SizeOfOptionalHeader + .short 0x306 @ Characteristics. + @ IMAGE_FILE_32BIT_MACHINE | + @ IMAGE_FILE_DEBUG_STRIPPED | + @ IMAGE_FILE_EXECUTABLE_IMAGE | + @ IMAGE_FILE_LINE_NUMS_STRIPPED + +optional_header: + .short 0x10b @ PE32 format + .byte 0x02 @ MajorLinkerVersion + .byte 0x14 @ MinorLinkerVersion + .long _end - __efi_start @ SizeOfCode + .long 0 @ SizeOfInitializedData + .long 0 @ SizeOfUninitializedData + .long efi_stub_entry - start @ AddressOfEntryPoint + .long start_offset @ BaseOfCode + .long 0 @ data + +extra_header_fields: + .long 0 @ ImageBase + .long 0x200 @ SectionAlignment + .long 0x200 @ FileAlignment + .short 0 @ MajorOperatingSystemVersion + .short 0 @ MinorOperatingSystemVersion + .short 0 @ MajorImageVersion + .short 0 @ MinorImageVersion + .short 0 @ MajorSubsystemVersion + .short 0 @ MinorSubsystemVersion + .long 0 @ Win32VersionValue + + .long _end - start @ SizeOfImage + .long start_offset @ SizeOfHeaders + .long 0 @ CheckSum + .short 0xa @ Subsystem (EFI application) + .short 0 @ DllCharacteristics + .long 0 @ SizeOfStackReserve + .long 0 @ SizeOfStackCommit + .long 0 @ SizeOfHeapReserve + .long 0 @ SizeOfHeapCommit + .long 0 @ LoaderFlags + .long 0x6 @ NumberOfRvaAndSizes + + .quad 0 @ ExportTable + .quad 0 @ ImportTable + .quad 0 @ ResourceTable + .quad 0 @ ExceptionTable + .quad 0 @ CertificationTable + .quad 0 @ BaseRelocationTable + +section_table: + @ + @ The EFI application loader requires a relocation section + @ because EFI applications must be relocatable. This is a + @ dummy section as far as we are concerned. + @ + .ascii ".reloc\0\0" + .long 0 @ VirtualSize + .long 0 @ VirtualAddress + .long 0 @ SizeOfRawData + .long 0 @ PointerToRawData + .long 0 @ PointerToRelocations + .long 0 @ PointerToLineNumbers + .short 0 @ NumberOfRelocations + .short 0 @ NumberOfLineNumbers + .long 0x42100040 @ Characteristics + + .ascii ".text\0\0\0" + .long _end - __efi_start @ VirtualSize + .long __efi_start @ VirtualAddress + .long _edata - __efi_start @ SizeOfRawData + .long __efi_start @ PointerToRawData + .long 0 @ PointerToRelocations + .long 0 @ PointerToLineNumbers + .short 0 @ NumberOfRelocations + .short 0 @ NumberOfLineNumbers + .long 0xe0500020 @ Characteristics + + .align 9 +__efi_start: +#endif + .endm diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 06e983f59980..af11c2f8f3b7 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -12,6 +12,8 @@ #include #include +#include "efi-header.S" + AR_CLASS( .arch armv7-a ) M_CLASS( .arch armv7-m ) @@ -126,7 +128,7 @@ start: .type start,#function .rept 7 - mov r0, r0 + __nop .endr ARM( mov r0, r0 ) ARM( b 1f ) @@ -139,7 +141,8 @@ start: .word 0x04030201 @ endianness flag THUMB( .thumb ) -1: +1: __EFI_HEADER + ARM_BE8( setend be ) @ go BE8 if compiled for BE8 AR_CLASS( mrs r9, cpsr ) #ifdef CONFIG_ARM_VIRT_EXT @@ -1353,6 +1356,53 @@ __enter_kernel: reloc_code_end: +#ifdef CONFIG_EFI_STUB + .align 2 +_start: .long start - . + +ENTRY(efi_stub_entry) + @ allocate space on stack for passing current zImage address + @ and for the EFI stub to return of new entry point of + @ zImage, as EFI stub may copy the kernel. Pointer address + @ is passed in r2. r0 and r1 are passed through from the + @ EFI firmware to efi_entry + adr ip, _start + ldr r3, [ip] + add r3, r3, ip + stmfd sp!, {r3, lr} + mov r2, sp @ pass zImage address in r2 + bl efi_entry + + @ Check for error return from EFI stub. r0 has FDT address + @ or error code. + cmn r0, #1 + beq efi_load_fail + + @ Preserve return value of efi_entry() in r4 + mov r4, r0 + bl cache_clean_flush + bl cache_off + + @ Set parameters for booting zImage according to boot protocol + @ put FDT address in r2, it was returned by efi_entry() + @ r1 is the machine type, and r0 needs to be 0 + mov r0, #0 + mov r1, #0xFFFFFFFF + mov r2, r4 + + @ Branch to (possibly) relocated zImage that is in [sp] + ldr lr, [sp] + ldr ip, =start_offset + add lr, lr, ip + mov pc, lr @ no mode switch + +efi_load_fail: + @ Return EFI_LOAD_ERROR to EFI firmware on error. + ldr r0, =0x80000001 + ldmfd sp!, {ip, pc} +ENDPROC(efi_stub_entry) +#endif + .align .section ".stack", "aw", %nobits .L_user_stack: .space 4096 diff --git a/arch/arm/boot/compressed/vmlinux.lds.S b/arch/arm/boot/compressed/vmlinux.lds.S index 2b60b843ac5e..81c493156ce8 100644 --- a/arch/arm/boot/compressed/vmlinux.lds.S +++ b/arch/arm/boot/compressed/vmlinux.lds.S @@ -48,6 +48,13 @@ SECTIONS *(.rodata) *(.rodata.*) } + .data : { + /* + * The EFI stub always executes from RAM, and runs strictly before the + * decompressor, so we can make an exception for its r/w data, and keep it + */ + *(.data.efistub) + } .piggydata : { *(.piggydata) } diff --git a/arch/arm/include/asm/efi.h b/arch/arm/include/asm/efi.h index c91e330616ad..e0eea72deb87 100644 --- a/arch/arm/include/asm/efi.h +++ b/arch/arm/include/asm/efi.h @@ -57,4 +57,27 @@ void efi_virtmap_unload(void); #define efi_init() #endif /* CONFIG_EFI */ +/* arch specific definitions used by the stub code */ + +#define efi_call_early(f, ...) sys_table_arg->boottime->f(__VA_ARGS__) + +/* + * A reasonable upper bound for the uncompressed kernel size is 32 MBytes, + * so we will reserve that amount of memory. We have no easy way to tell what + * the actuall size of code + data the uncompressed kernel will use. + * If this is insufficient, the decompressor will relocate itself out of the + * way before performing the decompression. + */ +#define MAX_UNCOMP_KERNEL_SIZE SZ_32M + +/* + * The kernel zImage should preferably be located between 32 MB and 128 MB + * from the base of DRAM. The min address leaves space for a maximal size + * uncompressed image, and the max address is due to how the zImage decompressor + * picks a destination address. + */ +#define ZIMAGE_OFFSET_LIMIT SZ_128M +#define MIN_ZIMAGE_OFFSET MAX_UNCOMP_KERNEL_SIZE +#define MAX_FDT_OFFSET ZIMAGE_OFFSET_LIMIT + #endif /* _ASM_ARM_EFI_H */ diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index 3c0467d3688c..8cf9ccbf42d5 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -34,6 +34,7 @@ $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \ $(patsubst %.c,lib-%.o,$(arm-deps)) +lib-$(CONFIG_ARM) += arm32-stub.o lib-$(CONFIG_ARM64) += arm64-stub.o CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) @@ -67,3 +68,11 @@ quiet_cmd_stubcopy = STUBCPY $@ $(OBJDUMP) -r $@ | grep $(STUBCOPY_RELOC-y) \ && (echo >&2 "$@: absolute symbol references not allowed in the EFI stub"; \ rm -f $@; /bin/false); else /bin/false; fi + +# +# ARM discards the .data section because it disallows r/w data in the +# decompressor. So move our .data to .data.efistub, which is preserved +# explicitly by the decompressor linker script. +# +STUBCOPY_FLAGS-$(CONFIG_ARM) += --rename-section .data=.data.efistub +STUBCOPY_RELOC-$(CONFIG_ARM) := R_ARM_ABS diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c index 950c87f5d279..3397902e4040 100644 --- a/drivers/firmware/efi/libstub/arm-stub.c +++ b/drivers/firmware/efi/libstub/arm-stub.c @@ -303,8 +303,10 @@ fail: * The value chosen is the largest non-zero power of 2 suitable for this purpose * both on 32-bit and 64-bit ARM CPUs, to maximize the likelihood that it can * be mapped efficiently. + * Since 32-bit ARM could potentially execute with a 1G/3G user/kernel split, + * map everything below 1 GB. */ -#define EFI_RT_VIRTUAL_BASE 0x40000000 +#define EFI_RT_VIRTUAL_BASE SZ_512M static int cmp_mem_desc(const void *l, const void *r) { diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c new file mode 100644 index 000000000000..495ebd657e38 --- /dev/null +++ b/drivers/firmware/efi/libstub/arm32-stub.c @@ -0,0 +1,85 @@ +/* + * Copyright (C) 2013 Linaro Ltd; + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include +#include + +efi_status_t handle_kernel_image(efi_system_table_t *sys_table, + unsigned long *image_addr, + unsigned long *image_size, + unsigned long *reserve_addr, + unsigned long *reserve_size, + unsigned long dram_base, + efi_loaded_image_t *image) +{ + unsigned long nr_pages; + efi_status_t status; + /* Use alloc_addr to tranlsate between types */ + efi_physical_addr_t alloc_addr; + + /* + * Verify that the DRAM base address is compatible with the ARM + * boot protocol, which determines the base of DRAM by masking + * off the low 27 bits of the address at which the zImage is + * loaded. These assumptions are made by the decompressor, + * before any memory map is available. + */ + dram_base = round_up(dram_base, SZ_128M); + + /* + * Reserve memory for the uncompressed kernel image. This is + * all that prevents any future allocations from conflicting + * with the kernel. Since we can't tell from the compressed + * image how much DRAM the kernel actually uses (due to BSS + * size uncertainty) we allocate the maximum possible size. + * Do this very early, as prints can cause memory allocations + * that may conflict with this. + */ + alloc_addr = dram_base; + *reserve_size = MAX_UNCOMP_KERNEL_SIZE; + nr_pages = round_up(*reserve_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; + status = sys_table->boottime->allocate_pages(EFI_ALLOCATE_ADDRESS, + EFI_LOADER_DATA, + nr_pages, &alloc_addr); + if (status != EFI_SUCCESS) { + *reserve_size = 0; + pr_efi_err(sys_table, "Unable to allocate memory for uncompressed kernel.\n"); + return status; + } + *reserve_addr = alloc_addr; + + /* + * Relocate the zImage, so that it appears in the lowest 128 MB + * memory window. + */ + *image_size = image->image_size; + status = efi_relocate_kernel(sys_table, image_addr, *image_size, + *image_size, + dram_base + MAX_UNCOMP_KERNEL_SIZE, 0); + if (status != EFI_SUCCESS) { + pr_efi_err(sys_table, "Failed to relocate kernel.\n"); + efi_free(sys_table, *reserve_size, *reserve_addr); + *reserve_size = 0; + return status; + } + + /* + * Check to see if we were able to allocate memory low enough + * in memory. The kernel determines the base of DRAM from the + * address at which the zImage is loaded. + */ + if (*image_addr + *image_size > dram_base + ZIMAGE_OFFSET_LIMIT) { + pr_efi_err(sys_table, "Failed to relocate kernel, no low memory available.\n"); + efi_free(sys_table, *reserve_size, *reserve_addr); + *reserve_size = 0; + efi_free(sys_table, *image_size, *image_addr); + *image_size = 0; + return EFI_LOAD_ERROR; + } + return EFI_SUCCESS; +} -- cgit v1.2.3