efi-entry.S (1510B)
1/* SPDX-License-Identifier: GPL-2.0-only */ 2/* 3 * EFI entry point. 4 * 5 * Copyright (C) 2013, 2014 Red Hat, Inc. 6 * Author: Mark Salter <msalter@redhat.com> 7 */ 8#include <linux/linkage.h> 9#include <linux/init.h> 10 11#include <asm/assembler.h> 12 13 __INIT 14 15SYM_CODE_START(efi_enter_kernel) 16 /* 17 * efi_pe_entry() will have copied the kernel image if necessary and we 18 * end up here with device tree address in x1 and the kernel entry 19 * point stored in x0. Save those values in registers which are 20 * callee preserved. 21 */ 22 ldr w2, =primary_entry_offset 23 add x19, x0, x2 // relocated Image entrypoint 24 mov x20, x1 // DTB address 25 26 /* 27 * Clean the copied Image to the PoC, and ensure it is not shadowed by 28 * stale icache entries from before relocation. 29 */ 30 ldr w1, =kernel_size 31 add x1, x0, x1 32 bl dcache_clean_poc 33 ic ialluis 34 35 /* 36 * Clean the remainder of this routine to the PoC 37 * so that we can safely disable the MMU and caches. 38 */ 39 adr x0, 0f 40 adr x1, 3f 41 bl dcache_clean_poc 420: 43 /* Turn off Dcache and MMU */ 44 mrs x0, CurrentEL 45 cmp x0, #CurrentEL_EL2 46 b.ne 1f 47 mrs x0, sctlr_el2 48 bic x0, x0, #1 << 0 // clear SCTLR.M 49 bic x0, x0, #1 << 2 // clear SCTLR.C 50 pre_disable_mmu_workaround 51 msr sctlr_el2, x0 52 isb 53 b 2f 541: 55 mrs x0, sctlr_el1 56 bic x0, x0, #1 << 0 // clear SCTLR.M 57 bic x0, x0, #1 << 2 // clear SCTLR.C 58 pre_disable_mmu_workaround 59 msr sctlr_el1, x0 60 isb 612: 62 /* Jump to kernel entry point */ 63 mov x0, x20 64 mov x1, xzr 65 mov x2, xzr 66 mov x3, xzr 67 br x19 683: 69SYM_CODE_END(efi_enter_kernel)