| Roy Franz | 81a0bc3 | 2015-09-23 20:17:54 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 Linaro Ltd; <roy.franz@linaro.org> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | */ |
| 9 | #include <linux/efi.h> |
| 10 | #include <asm/efi.h> |
| 11 | |
| 12 | efi_status_t handle_kernel_image(efi_system_table_t *sys_table, |
| 13 | unsigned long *image_addr, |
| 14 | unsigned long *image_size, |
| 15 | unsigned long *reserve_addr, |
| 16 | unsigned long *reserve_size, |
| 17 | unsigned long dram_base, |
| 18 | efi_loaded_image_t *image) |
| 19 | { |
| 20 | unsigned long nr_pages; |
| 21 | efi_status_t status; |
| 22 | /* Use alloc_addr to tranlsate between types */ |
| 23 | efi_physical_addr_t alloc_addr; |
| 24 | |
| 25 | /* |
| 26 | * Verify that the DRAM base address is compatible with the ARM |
| 27 | * boot protocol, which determines the base of DRAM by masking |
| 28 | * off the low 27 bits of the address at which the zImage is |
| 29 | * loaded. These assumptions are made by the decompressor, |
| 30 | * before any memory map is available. |
| 31 | */ |
| 32 | dram_base = round_up(dram_base, SZ_128M); |
| 33 | |
| 34 | /* |
| 35 | * Reserve memory for the uncompressed kernel image. This is |
| 36 | * all that prevents any future allocations from conflicting |
| 37 | * with the kernel. Since we can't tell from the compressed |
| 38 | * image how much DRAM the kernel actually uses (due to BSS |
| 39 | * size uncertainty) we allocate the maximum possible size. |
| 40 | * Do this very early, as prints can cause memory allocations |
| 41 | * that may conflict with this. |
| 42 | */ |
| 43 | alloc_addr = dram_base; |
| 44 | *reserve_size = MAX_UNCOMP_KERNEL_SIZE; |
| 45 | nr_pages = round_up(*reserve_size, EFI_PAGE_SIZE) / EFI_PAGE_SIZE; |
| 46 | status = sys_table->boottime->allocate_pages(EFI_ALLOCATE_ADDRESS, |
| 47 | EFI_LOADER_DATA, |
| 48 | nr_pages, &alloc_addr); |
| 49 | if (status != EFI_SUCCESS) { |
| 50 | *reserve_size = 0; |
| 51 | pr_efi_err(sys_table, "Unable to allocate memory for uncompressed kernel.\n"); |
| 52 | return status; |
| 53 | } |
| 54 | *reserve_addr = alloc_addr; |
| 55 | |
| 56 | /* |
| 57 | * Relocate the zImage, so that it appears in the lowest 128 MB |
| 58 | * memory window. |
| 59 | */ |
| 60 | *image_size = image->image_size; |
| 61 | status = efi_relocate_kernel(sys_table, image_addr, *image_size, |
| 62 | *image_size, |
| 63 | dram_base + MAX_UNCOMP_KERNEL_SIZE, 0); |
| 64 | if (status != EFI_SUCCESS) { |
| 65 | pr_efi_err(sys_table, "Failed to relocate kernel.\n"); |
| 66 | efi_free(sys_table, *reserve_size, *reserve_addr); |
| 67 | *reserve_size = 0; |
| 68 | return status; |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * Check to see if we were able to allocate memory low enough |
| 73 | * in memory. The kernel determines the base of DRAM from the |
| 74 | * address at which the zImage is loaded. |
| 75 | */ |
| 76 | if (*image_addr + *image_size > dram_base + ZIMAGE_OFFSET_LIMIT) { |
| 77 | pr_efi_err(sys_table, "Failed to relocate kernel, no low memory available.\n"); |
| 78 | efi_free(sys_table, *reserve_size, *reserve_addr); |
| 79 | *reserve_size = 0; |
| 80 | efi_free(sys_table, *image_size, *image_addr); |
| 81 | *image_size = 0; |
| 82 | return EFI_LOAD_ERROR; |
| 83 | } |
| 84 | return EFI_SUCCESS; |
| 85 | } |