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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_EFI_H
#define _ASM_EFI_H
#include <asm/boot.h>
#include <asm/cpufeature.h>
#include <asm/fpsimd.h>
#include <asm/io.h>
#include <asm/memory.h>
#include <asm/mmu_context.h>
#include <asm/neon.h>
#include <asm/ptrace.h>
#include <asm/tlbflush.h>
#ifdef CONFIG_EFI
extern void efi_init(void);
bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg);
#else
#define efi_init()
static inline
bool efi_runtime_fixup_exception(struct pt_regs *regs, const char *msg)
{
return false;
}
#endif
int efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md);
int efi_set_mapping_permissions(struct mm_struct *mm, efi_memory_desc_t *md,
bool has_bti);
#define arch_efi_call_virt_setup() \
({ \
efi_virtmap_load(); \
__efi_fpsimd_begin(); \
raw_spin_lock(&efi_rt_lock); \
})
#undef arch_efi_call_virt
#define arch_efi_call_virt(p, f, args...) \
__efi_rt_asm_wrapper((p)->f, #f, args)
#define arch_efi_call_virt_teardown() \
({ \
raw_spin_unlock(&efi_rt_lock); \
__efi_fpsimd_end(); \
efi_virtmap_unload(); \
})
extern raw_spinlock_t efi_rt_lock;
extern u64 *efi_rt_stack_top;
efi_status_t __efi_rt_asm_wrapper(void *, const char *, ...);
/*
* efi_rt_stack_top[-1] contains the value the stack pointer had before
* switching to the EFI runtime stack.
*/
#define current_in_efi() \
(!preemptible() && efi_rt_stack_top != NULL && \
on_task_stack(current, READ_ONCE(efi_rt_stack_top[-1]), 1))
#define ARCH_EFI_IRQ_FLAGS_MASK (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)
/*
* Even when Linux uses IRQ priorities for IRQ disabling, EFI does not.
* And EFI shouldn't really play around with priority masking as it is not aware
* which priorities the OS has assigned to its interrupts.
*/
#define arch_efi_save_flags(state_flags) \
((void)((state_flags) = read_sysreg(daif)))
#define arch_efi_restore_flags(state_flags) write_sysreg(state_flags, daif)
/* arch specific definitions used by the stub code */
/*
* In some configurations (e.g. VMAP_STACK && 64K pages), stacks built into the
* kernel need greater alignment than we require the segments to be padded to.
*/
#define EFI_KIMG_ALIGN \
(SEGMENT_ALIGN > THREAD_ALIGN ? SEGMENT_ALIGN : THREAD_ALIGN)
/*
* On arm64, we have to ensure that the initrd ends up in the linear region,
* which is a 1 GB aligned region of size '1UL << (VA_BITS_MIN - 1)' that is
* guaranteed to cover the kernel Image.
*
* Since the EFI stub is part of the kernel Image, we can relax the
* usual requirements in Documentation/arch/arm64/booting.rst, which still
* apply to other bootloaders, and are required for some kernel
* configurations.
*/
static inline unsigned long efi_get_max_initrd_addr(unsigned long image_addr)
{
return (image_addr & ~(SZ_1G - 1UL)) + (1UL << (VA_BITS_MIN - 1));
}
static inline unsigned long efi_get_kimg_min_align(void)
{
extern bool efi_nokaslr;
/*
* Although relocatable kernels can fix up the misalignment with
* respect to MIN_KIMG_ALIGN, the resulting virtual text addresses are
* subtly out of sync with those recorded in the vmlinux when kaslr is
* disabled but the image required relocation anyway. Therefore retain
* 2M alignment if KASLR was explicitly disabled, even if it was not
* going to be activated to begin with.
*/
return efi_nokaslr ? MIN_KIMG_ALIGN : EFI_KIMG_ALIGN;
}
#define EFI_ALLOC_ALIGN SZ_64K
#define EFI_ALLOC_LIMIT ((1UL << 48) - 1)
extern unsigned long primary_entry_offset(void);
/*
* On ARM systems, virtually remapped UEFI runtime services are set up in two
* distinct stages:
* - The stub retrieves the final version of the memory map from UEFI, populates
* the virt_addr fields and calls the SetVirtualAddressMap() [SVAM] runtime
* service to communicate the new mapping to the firmware (Note that the new
* mapping is not live at this time)
* - During an early initcall(), the EFI system table is permanently remapped
* and the virtual remapping of the UEFI Runtime Services regions is loaded
* into a private set of page tables. If this all succeeds, the Runtime
* Services are enabled and the EFI_RUNTIME_SERVICES bit set.
*/
static inline void efi_set_pgd(struct mm_struct *mm)
{
__switch_mm(mm);
if (system_uses_ttbr0_pan()) {
if (mm != current->active_mm) {
/*
* Update the current thread's saved ttbr0 since it is
* restored as part of a return from exception. Enable
* access to the valid TTBR0_EL1 and invoke the errata
* workaround directly since there is no return from
* exception when invoking the EFI run-time services.
*/
update_saved_ttbr0(current, mm);
uaccess_ttbr0_enable();
post_ttbr_update_workaround();
} else {
/*
* Defer the switch to the current thread's TTBR0_EL1
* until uaccess_enable(). Restore the current
* thread's saved ttbr0 corresponding to its active_mm
*/
uaccess_ttbr0_disable();
update_saved_ttbr0(current, current->active_mm);
}
}
}
void efi_virtmap_load(void);
void efi_virtmap_unload(void);
static inline void efi_capsule_flush_cache_range(void *addr, int size)
{
dcache_clean_inval_poc((unsigned long)addr, (unsigned long)addr + size);
}
efi_status_t efi_handle_corrupted_x18(efi_status_t s, const char *f);
#endif /* _ASM_EFI_H */
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