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linux
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 <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
authored by
Ard Biesheuvel
and committed by
Will Deacon
f7d92489
e5bc22a4
+54
-35
+9
arch/arm64/include/asm/efi.h
+9
arch/arm64/include/asm/efi.h
···
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#define _ASM_EFI_H
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#include <asm/io.h>
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#include <asm/mmu_context.h>
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#include <asm/neon.h>
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#include <asm/tlbflush.h>
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#ifdef CONFIG_EFI
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extern void efi_init(void);
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#else
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#define efi_init()
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#endif
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int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
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#define efi_call_virt(f, ...) \
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({ \
···
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* into a private set of page tables. If this all succeeds, the Runtime
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* Services are enabled and the EFI_RUNTIME_SERVICES bit set.
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*/
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static inline void efi_set_pgd(struct mm_struct *mm)
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{
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switch_mm(NULL, mm, NULL);
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}
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void efi_virtmap_load(void);
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void efi_virtmap_unload(void);
+23
arch/arm64/kernel/efi.c
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arch/arm64/kernel/efi.c
···
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#include <asm/efi.h>
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int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
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{
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pteval_t prot_val;
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/*
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* Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
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* executable, everything else can be mapped with the XN bits
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* set.
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*/
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if ((md->attribute & EFI_MEMORY_WB) == 0)
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prot_val = PROT_DEVICE_nGnRE;
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else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
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!PAGE_ALIGNED(md->phys_addr))
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prot_val = pgprot_val(PAGE_KERNEL_EXEC);
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else
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prot_val = pgprot_val(PAGE_KERNEL);
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create_pgd_mapping(mm, md->phys_addr, md->virt_addr,
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md->num_pages << EFI_PAGE_SHIFT,
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__pgprot(prot_val | PTE_NG));
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return 0;
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}
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static int __init arm64_dmi_init(void)
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{
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/*
+4
-3
drivers/firmware/efi/arm-init.c
+4
-3
drivers/firmware/efi/arm-init.c
···
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{
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efi_char16_t *c16;
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void *config_tables;
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-
u64 table_size;
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size_t table_size;
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char vendor[100] = "unknown";
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int i, retval;
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···
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}
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set_bit(EFI_BOOT, &efi.flags);
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-
set_bit(EFI_64BIT, &efi.flags);
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if (IS_ENABLED(CONFIG_64BIT))
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set_bit(EFI_64BIT, &efi.flags);
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/*
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* Verify the EFI Table
···
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goto out;
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}
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retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables,
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-
sizeof(efi_config_table_64_t), NULL);
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sizeof(efi_config_table_t), NULL);
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early_memunmap(config_tables, table_size);
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out:
+16
-32
drivers/firmware/efi/arm-runtime.c
+16
-32
drivers/firmware/efi/arm-runtime.c
···
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*/
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#include <linux/efi.h>
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#include <linux/io.h>
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#include <linux/memblock.h>
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#include <linux/mm_types.h>
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#include <linux/preempt.h>
···
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#include <asm/cacheflush.h>
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#include <asm/efi.h>
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-
#include <asm/tlbflush.h>
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-
#include <asm/mmu_context.h>
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#include <asm/mmu.h>
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#include <asm/pgalloc.h>
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#include <asm/pgtable.h>
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-
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static pgd_t efi_pgd[PTRS_PER_PGD] __page_aligned_bss;
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extern u64 efi_system_table;
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static struct mm_struct efi_mm = {
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.mm_rb = RB_ROOT,
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.pgd = efi_pgd,
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.mm_users = ATOMIC_INIT(2),
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.mm_count = ATOMIC_INIT(1),
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.mmap_sem = __RWSEM_INITIALIZER(efi_mm.mmap_sem),
···
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{
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efi_memory_desc_t *md;
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efi_mm.pgd = pgd_alloc(&efi_mm);
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init_new_context(NULL, &efi_mm);
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for_each_efi_memory_desc(&memmap, md) {
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pgprot_t prot;
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phys_addr_t phys = md->phys_addr;
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int ret;
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if (!(md->attribute & EFI_MEMORY_RUNTIME))
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continue;
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if (md->virt_addr == 0)
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return false;
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pr_info(" EFI remap 0x%016llx => %p\n",
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md->phys_addr, (void *)md->virt_addr);
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/*
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* Only regions of type EFI_RUNTIME_SERVICES_CODE need to be
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* executable, everything else can be mapped with the XN bits
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* set.
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*/
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if ((md->attribute & EFI_MEMORY_WB) == 0)
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prot = __pgprot(PROT_DEVICE_nGnRE);
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else if (md->type == EFI_RUNTIME_SERVICES_CODE ||
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!PAGE_ALIGNED(md->phys_addr))
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prot = PAGE_KERNEL_EXEC;
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else
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prot = PAGE_KERNEL;
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create_pgd_mapping(&efi_mm, md->phys_addr, md->virt_addr,
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md->num_pages << EFI_PAGE_SHIFT,
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__pgprot(pgprot_val(prot) | PTE_NG));
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ret = efi_create_mapping(&efi_mm, md);
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if (!ret) {
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pr_info(" EFI remap %pa => %p\n",
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&phys, (void *)(unsigned long)md->virt_addr);
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} else {
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pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
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&phys, ret);
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return false;
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}
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}
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return true;
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}
···
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* non-early mapping of the UEFI system table and virtual mappings for all
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* EFI_MEMORY_RUNTIME regions.
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*/
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static int __init arm64_enable_runtime_services(void)
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static int __init arm_enable_runtime_services(void)
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{
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u64 mapsize;
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···
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return 0;
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}
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early_initcall(arm64_enable_runtime_services);
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static void efi_set_pgd(struct mm_struct *mm)
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{
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switch_mm(NULL, mm, NULL);
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}
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early_initcall(arm_enable_runtime_services);
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void efi_virtmap_load(void)
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{