diff options
Diffstat (limited to 'src/arch/arm64')
-rw-r--r-- | src/arch/arm64/Makefile.inc | 1 | ||||
-rw-r--r-- | src/arch/arm64/fit_payload.c | 262 |
2 files changed, 263 insertions, 0 deletions
diff --git a/src/arch/arm64/Makefile.inc b/src/arch/arm64/Makefile.inc index f57ef720b9..3c3cd20370 100644 --- a/src/arch/arm64/Makefile.inc +++ b/src/arch/arm64/Makefile.inc @@ -136,6 +136,7 @@ ramstage-y += memcpy.S ramstage-y += memmove.S ramstage-$(CONFIG_ARM64_USE_ARM_TRUSTED_FIRMWARE) += arm_tf.c ramstage-y += transition.c transition_asm.S +ramstage-$(CONFIG_PAYLOAD_FIT_SUPPORT) += fit_payload.c rmodules_arm64-y += memset.S rmodules_arm64-y += memcpy.S diff --git a/src/arch/arm64/fit_payload.c b/src/arch/arm64/fit_payload.c new file mode 100644 index 0000000000..c4bbceee4c --- /dev/null +++ b/src/arch/arm64/fit_payload.c @@ -0,0 +1,262 @@ +/* + * Copyright 2013 Google Inc. + * Copyright 2018 Facebook, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <console/console.h> +#include <bootmem.h> +#include <stdlib.h> +#include <program_loading.h> +#include <string.h> +#include <commonlib/compression.h> +#include <commonlib/cbfs_serialized.h> +#include <lib.h> +#include <fit.h> +#include <endian.h> + +#define MAX_KERNEL_SIZE (64*MiB) + +struct arm64_kernel_header { + u32 code0; + u32 code1; + u64 text_offset; + u64 image_size; + u64 flags; + u64 res2; + u64 res3; + u64 res4; + u32 magic; +#define KERNEL_HEADER_MAGIC 0x644d5241 + u32 res5; +}; + +static struct { + union { + struct arm64_kernel_header header; + u8 raw[sizeof(struct arm64_kernel_header) + 0x100]; + }; +#define SCRATCH_CANARY_VALUE 0xdeadbeef + u32 canary; +} scratch; + +/* Returns true if decompressing was successful and it looks like a kernel. */ +static bool decompress_kernel_header(const struct fit_image_node *node) +{ + /* Partially decompress to get text_offset. Can't check for errors. */ + scratch.canary = SCRATCH_CANARY_VALUE; + switch (node->compression) { + case CBFS_COMPRESS_NONE: + memcpy(scratch.raw, node->data, sizeof(scratch.raw)); + break; + case CBFS_COMPRESS_LZMA: + ulzman(node->data, node->size, + scratch.raw, sizeof(scratch.raw)); + break; + case CBFS_COMPRESS_LZ4: + ulz4fn(node->data, node->size, + scratch.raw, sizeof(scratch.raw)); + break; + default: + printk(BIOS_ERR, "ERROR: Unsupported compression algorithm!\n"); + return false; + } + + /* Should never happen, but if it does we'll want to know. */ + if (scratch.canary != SCRATCH_CANARY_VALUE) + die("ERROR: Partial decompression ran over scratchbuf!\n"); + + if (scratch.header.magic != KERNEL_HEADER_MAGIC) { + printk(BIOS_ERR, + "ERROR: Invalid kernel magic: %#.8x\n != %#.8x\n", + scratch.header.magic, KERNEL_HEADER_MAGIC); + return false; + } + + /** + * Prior to v3.17, the endianness of text_offset was not specified. In + * these cases image_size is zero and text_offset is 0x80000 in the + * endianness of the kernel. Where image_size is non-zero image_size is + * little-endian and must be respected. Where image_size is zero, + * text_offset can be assumed to be 0x80000. + */ + if (!scratch.header.image_size) + scratch.header.text_offset = cpu_to_le64(0x80000); + + return true; +} + +static size_t get_kernel_size(const struct fit_image_node *node) +{ + if (scratch.header.image_size) + return le64_to_cpu(scratch.header.image_size); + + /** + * When image_size is zero, a bootloader should attempt to keep as much + * memory as possible free for use by the kernel immediately after the + * end of the kernel image. The amount of space required will vary + * depending on selected features, and is effectively unbound. + */ + + printk(BIOS_WARNING, "FIT: image_size not set in kernel header.\n" + "Leaving additional %u MiB of free space after kernel.\n", + MAX_KERNEL_SIZE >> 20); + + return node->size + MAX_KERNEL_SIZE; +} + +static bool fit_place_kernel(const struct range_entry *r, void *arg) +{ + struct region *region = arg; + resource_t start; + + if (range_entry_tag(r) != BM_MEM_RAM) + return true; + + /** + * The Image must be placed text_offset bytes from a 2MB aligned base + * address anywhere in usable system RAM and called there. The region + * between the 2 MB aligned base address and the start of the image has + * no special significance to the kernel, and may be used for other + * purposes. + * + * If the reserved memory (BL31 for example) is smaller than text_offset + * we can use the 2 MiB base address, otherwise use the next 2 MiB page. + * It's not mandatory, but wastes less memory below the kernel. + */ + start = ALIGN_DOWN(range_entry_base(r), 2 * MiB) + + le64_to_cpu(scratch.header.text_offset); + + if (start < range_entry_base(r)) + start += 2 * MiB; + /** + * At least image_size bytes from the start of the image must be free + * for use by the kernel. + */ + if (start + region->size < range_entry_end(r)) { + region->offset = (size_t)start; + return false; + } + + return true; +} + +/** + * Place the region in free memory range. + * + * The caller has to set region->offset to the minimum allowed address. + * The region->offset is usually 0 on kernel >v4.6 and kernel_base + kernel_size + * on kernel <v4.6. + */ +static bool fit_place_mem(const struct range_entry *r, void *arg) +{ + struct region *region = arg; + resource_t start; + + if (range_entry_tag(r) != BM_MEM_RAM) + return true; + + /* Linux 4.15 doesn't like 4KiB alignment. Align to 1 MiB for now. */ + start = ALIGN_UP(MAX(region->offset, range_entry_base(r)), 1 * MiB); + + if (start + region->size < range_entry_end(r)) { + region->offset = (size_t)start; + return false; + } + + return true; +} + +bool fit_payload_arch(struct prog *payload, struct fit_config_node *config, + struct region *kernel, + struct region *fdt, + struct region *initrd) +{ + bool place_anywhere; + void *arg = NULL; + + if (!config->fdt || !fdt) { + printk(BIOS_CRIT, "CRIT: Providing a valid FDT is mandatory to " + "boot an ARM64 kernel!\n"); + return false; + } + + if (!decompress_kernel_header(config->kernel_node)) { + printk(BIOS_CRIT, "CRIT: Payload doesn't look like an ARM64" + " kernel Image.\n"); + return false; + } + + /* Update kernel size from image header, if possible */ + kernel->size = get_kernel_size(config->kernel_node); + printk(BIOS_DEBUG, "FIT: Using kernel size of 0x%zx bytes\n", + kernel->size); + + /** + * The code assumes that bootmem_walk provides a sorted list of memory + * regions, starting from the lowest address. + * The order of the calls here doesn't matter, as the placement is + * enforced in the called functions. + * For details check code on top. + */ + + if (!bootmem_walk(fit_place_kernel, kernel)) + return false; + + /* Mark as reserved for future allocations. */ + bootmem_add_range(kernel->offset, kernel->size, BM_MEM_PAYLOAD); + + /** + * NOTE: versions prior to v4.6 cannot make use of memory below the + * physical offset of the Image so it is recommended that the Image be + * placed as close as possible to the start of system RAM. + * + * For kernel <v4.6 the INITRD and FDT can't be placed below the kernel. + * In that case set region offset to an address on top of kernel. + */ + place_anywhere = !!(le64_to_cpu(scratch.header.flags) & (1 << 3)); + printk(BIOS_DEBUG, "FIT: Placing FDT and INITRD %s\n", + place_anywhere ? "anywhere" : "on top of kernel"); + + /* Place INITRD */ + if (config->ramdisk) { + if (place_anywhere) + initrd->offset = 0; + else + initrd->offset = kernel->offset + kernel->size; + + if (!bootmem_walk(fit_place_mem, initrd)) + return false; + /* Mark as reserved for future allocations. */ + bootmem_add_range(initrd->offset, initrd->size, BM_MEM_PAYLOAD); + } + + /* Place FDT */ + if (place_anywhere) + fdt->offset = 0; + else + fdt->offset = kernel->offset + kernel->size; + + if (!bootmem_walk(fit_place_mem, fdt)) + return false; + /* Mark as reserved for future allocations. */ + bootmem_add_range(fdt->offset, fdt->size, BM_MEM_PAYLOAD); + + /* Kernel expects FDT as argument */ + arg = (void *)fdt->offset; + + prog_set_entry(payload, (void *)kernel->offset, arg); + + bootmem_dump_ranges(); + + return true; +} |