| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * EFI entry point. |
| * |
| * Copyright (C) 2013, 2014 Red Hat, Inc. |
| * Author: Mark Salter <msalter@redhat.com> |
| */ |
| #include <linux/linkage.h> |
| #include <linux/init.h> |
| |
| #include <asm/assembler.h> |
| |
| __INIT |
| |
| SYM_CODE_START(efi_enter_kernel) |
| /* |
| * efi_pe_entry() will have copied the kernel image if necessary and we |
| * 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. |
| */ |
| ldr w2, =primary_entry_offset |
| add x19, x0, x2 // relocated Image entrypoint |
| mov x20, x1 // DTB address |
| |
| /* |
| * Clean the copied Image to the PoC, and ensure it is not shadowed by |
| * stale icache entries from before relocation. |
| */ |
| ldr w1, =kernel_size |
| bl __clean_dcache_area_poc |
| ic ialluis |
| |
| /* |
| * Clean the remainder of this routine to the PoC |
| * so that we can safely disable the MMU and caches. |
| */ |
| adr x0, 0f |
| ldr w1, 3f |
| bl __clean_dcache_area_poc |
| 0: |
| /* Turn off Dcache and MMU */ |
| mrs x0, CurrentEL |
| cmp x0, #CurrentEL_EL2 |
| b.ne 1f |
| mrs x0, sctlr_el2 |
| bic x0, x0, #1 << 0 // clear SCTLR.M |
| bic x0, x0, #1 << 2 // clear SCTLR.C |
| pre_disable_mmu_workaround |
| msr sctlr_el2, x0 |
| isb |
| b 2f |
| 1: |
| mrs x0, sctlr_el1 |
| bic x0, x0, #1 << 0 // clear SCTLR.M |
| bic x0, x0, #1 << 2 // clear SCTLR.C |
| pre_disable_mmu_workaround |
| msr sctlr_el1, x0 |
| isb |
| 2: |
| /* Jump to kernel entry point */ |
| mov x0, x20 |
| mov x1, xzr |
| mov x2, xzr |
| mov x3, xzr |
| br x19 |
| SYM_CODE_END(efi_enter_kernel) |
| 3: .long . - 0b |
