diff options
Diffstat (limited to 'arch/arm64/kernel/efi-entry.S')
| -rw-r--r-- | arch/arm64/kernel/efi-entry.S | 86 |
1 files changed, 17 insertions, 69 deletions
diff --git a/arch/arm64/kernel/efi-entry.S b/arch/arm64/kernel/efi-entry.S index 304d5b02ca67..4cfd03c35c49 100644 --- a/arch/arm64/kernel/efi-entry.S +++ b/arch/arm64/kernel/efi-entry.S @@ -10,81 +10,35 @@ #include <asm/assembler.h> -#define EFI_LOAD_ERROR 0x8000000000000001 - __INIT - /* - * We arrive here from the EFI boot manager with: - * - * * CPU in little-endian mode - * * MMU on with identity-mapped RAM - * * Icache and Dcache on - * - * We will most likely be running from some place other than where - * we want to be. The kernel image wants to be placed at TEXT_OFFSET - * from start of RAM. - */ -ENTRY(entry) - /* - * Create a stack frame to save FP/LR with extra space - * for image_addr variable passed to efi_entry(). - */ - stp x29, x30, [sp, #-32]! - mov x29, sp - - /* - * Call efi_entry to do the real work. - * x0 and x1 are already set up by firmware. Current runtime - * address of image is calculated and passed via *image_addr. - * - * unsigned long efi_entry(void *handle, - * efi_system_table_t *sys_table, - * unsigned long *image_addr) ; - */ - adr_l x8, _text - add x2, sp, 16 - str x8, [x2] - bl efi_entry - cmn x0, #1 - b.eq efi_load_fail - +ENTRY(efi_enter_kernel) /* * efi_entry() will have copied the kernel image if necessary and we - * return here with device tree address in x0 and the kernel entry - * point stored at *image_addr. Save those values in registers which - * are callee preserved. - */ - mov x20, x0 // DTB address - ldr x0, [sp, #16] // relocated _text address - ldr w21, =stext_offset - add x21, x0, x21 - - /* - * Calculate size of the kernel Image (same for original and copy). + * end up here with device tree address in x1 and the kernel entry + * point stored in x0. Save those values in registers which are + * callee preserved. */ - adr_l x1, _text - adr_l x2, _edata - sub x1, x2, x1 + mov x19, x0 // relocated Image address + mov x20, x1 // DTB address /* * Flush the copied Image to the PoC, and ensure it is not shadowed by * stale icache entries from before relocation. */ + ldr w1, =kernel_size bl __flush_dcache_area ic ialluis + dsb sy /* - * Ensure that the rest of this function (in the original Image) is - * visible when the caches are disabled. The I-cache can't have stale - * entries for the VA range of the current image, so no maintenance is - * necessary. + * Jump across, into the copy of the image that we just cleaned + * to the PoC, so that we can safely disable the MMU and caches. */ - adr x0, entry - adr x1, entry_end - sub x1, x1, x0 - bl __flush_dcache_area - + ldr w0, .Ljmp + sub x0, x19, w0, sxtw + br x0 +0: /* Turn off Dcache and MMU */ mrs x0, CurrentEL cmp x0, #CurrentEL_EL2 @@ -109,12 +63,6 @@ ENTRY(entry) mov x1, xzr mov x2, xzr mov x3, xzr - br x21 - -efi_load_fail: - mov x0, #EFI_LOAD_ERROR - ldp x29, x30, [sp], #32 - ret - -entry_end: -ENDPROC(entry) + b stext +ENDPROC(efi_enter_kernel) +.Ljmp: .long _text - 0b |