coreboot-kgpe-d16/util/cbfstool/cbfs-payload-linux.c

322 lines
8.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
#include "cbfs.h"
#include "linux.h"
/* trampoline */
extern unsigned char trampoline[];
extern unsigned int trampoline_len;
/*
* Current max number of segments include:
*
* 1. parameters
* 2. kernel
* 3. trampoline
* 4. optional cmdline
* 5. optional initrd
* 6. terminating entry segment
*/
#define MAX_NUM_SEGMENTS 6
struct bzpayload {
/* Input variables. */
int num_segments;
struct cbfs_payload_segment segs[MAX_NUM_SEGMENTS];
struct buffer parameters;
struct buffer kernel;
struct buffer trampoline;
struct buffer cmdline;
struct buffer initrd;
/* Output variables. */
enum cbfs_compression algo;
comp_func_ptr compress;
struct buffer output;
size_t offset;
struct cbfs_payload_segment *out_seg;
};
static int bzp_init(struct bzpayload *bzp, enum cbfs_compression algo)
{
memset(bzp, 0, sizeof(*bzp));
/*
* Need at least the terminating entry segment.
*/
bzp->num_segments = 1;
bzp->algo = algo;
bzp->compress = compression_function(algo);
if (bzp->compress == NULL) {
ERROR("Invalid compression algorithm specified.\n");
return -1;
}
return 0;
}
static int bzp_add_initrd(struct bzpayload *bzp, const char *fname)
{
if (fname == NULL)
return 0;
if (buffer_from_file(&bzp->initrd, fname)) {
ERROR("could not open initrd.\n");
return -1;
}
bzp->num_segments++;
return 0;
}
static void bzp_add_segment(struct bzpayload *bzp, struct buffer *b, void *data,
size_t size)
{
buffer_init(b, NULL, data, size);
bzp->num_segments++;
}
static int bzp_add_trampoline(struct bzpayload *bzp)
{
bzp_add_segment(bzp, &bzp->trampoline, trampoline,
trampoline_len);
return 0;
}
static int bzp_add_cmdline(struct bzpayload *bzp, char *cmdline)
{
if (cmdline == NULL)
return 0;
bzp_add_segment(bzp, &bzp->cmdline, cmdline, strlen(cmdline) + 1);
return 0;
}
static int bzp_add_params(struct bzpayload *bzp, struct linux_params *params)
{
bzp_add_segment(bzp, &bzp->parameters, params, sizeof(*params));
return 0;
}
static int bzp_add_kernel(struct bzpayload *bzp, const struct buffer *in,
size_t setup_size)
{
char *input = buffer_get(in);
size_t kern_sz = buffer_size(in) - setup_size;
bzp_add_segment(bzp, &bzp->kernel, &input[setup_size], kern_sz);
return 0;
}
static int bzp_init_output(struct bzpayload *bzp, const char *name)
{
size_t sz = 0;
sz += buffer_size(&bzp->parameters);
sz += buffer_size(&bzp->kernel);
sz += buffer_size(&bzp->trampoline);
sz += buffer_size(&bzp->cmdline);
sz += buffer_size(&bzp->initrd);
bzp->offset = bzp->num_segments * sizeof(struct cbfs_payload_segment);
sz += bzp->offset;
if (buffer_create(&bzp->output, sz, name) != 0)
return -1;
bzp->out_seg = &bzp->segs[0];
return 0;
}
static void bzp_output_segment(struct bzpayload *bzp, struct buffer *b,
uint32_t type, uint64_t load_addr)
{
struct buffer out;
struct cbfs_payload_segment *seg;
int len = 0;
/* Don't process empty buffers. */
if (b != NULL && buffer_size(b) == 0)
return;
seg = bzp->out_seg;
seg->type = type;
seg->load_addr = load_addr;
bzp->out_seg++;
/* No buffer associated with segment. */
if (b == NULL)
return;
/* Use a temp buffer for easier management. */
buffer_splice(&out, &bzp->output, bzp->offset, buffer_size(b));
seg->mem_len = buffer_size(b);
seg->offset = bzp->offset;
bzp->compress(buffer_get(b), buffer_size(b), buffer_get(&out), &len);
seg->compression = bzp->algo;
seg->len = len;
/* Update output offset. */
bzp->offset += len;
}
/* TODO:
* handle special arguments
* mem= argument - only affects loading decisions (kernel + initrd), not e820 -> build time
* vga= argument (FILO ignores this)
* add support for more parameters to trampoline:
* alt_mem_k, ext_mem_k (not strictly necessary since e820 takes precedence)
* framebuffer/console values
*
* larger work:
* is compress() safe to use in a size constrained buffer? ie. do(es) the
* compression algorithm(s) stop once the compression result reaches input
* size (ie. incompressible data)?
*/
int parse_bzImage_to_payload(const struct buffer *input,
struct buffer *output, const char *initrd_name,
char *cmdline, enum cbfs_compression algo)
{
struct bzpayload bzp;
unsigned int initrd_base = 64*1024*1024;
struct linux_header *hdr = (struct linux_header *)input->data;
unsigned int setup_size = 4 * 512;
if (bzp_init(&bzp, algo) != 0)
return -1;
if (bzp_add_trampoline(&bzp) != 0)
return -1;
if (bzp_add_initrd(&bzp, initrd_name) != 0)
return -1;
if (bzp_add_cmdline(&bzp, cmdline) != 0)
return -1;
if (hdr->setup_sects != 0) {
setup_size = (hdr->setup_sects + 1) * 512;
} else {
WARN("hdr->setup_sects is 0, which could cause boot problems.\n");
}
/* Setup parameter block. Imitate FILO. */
struct linux_params params;
memset(&params, 0, sizeof(struct linux_params));
params.mount_root_rdonly = hdr->root_flags;
params.orig_root_dev = hdr->root_dev;
params.init_size = hdr->init_size;
/* Sensible video defaults. Might be overridden on runtime by coreboot tables. */
params.orig_video_mode = 3;
params.orig_video_cols = 80;
params.orig_video_lines = 25;
params.orig_video_isVGA = 1;
params.orig_video_points = 16;
params.loader_type = 0xff; /* Unregistered Linux loader */
if (cmdline != NULL) {
if (hdr->protocol_version < 0x202) {
params.cl_magic = CL_MAGIC_VALUE;
params.cl_offset = COMMAND_LINE_LOC - LINUX_PARAM_LOC;
} else {
params.cmd_line_ptr = COMMAND_LINE_LOC;
}
}
unsigned long kernel_base = 0x100000;
if ((hdr->protocol_version < 0x200) || !(hdr->loadflags & 1)) {
kernel_base = 0x1000; /* zImage kernel */
}
/* kernel prefers an address, so listen */
if ((hdr->protocol_version >= 0x20a) && (!(hdr->pref_address >> 32))) {
kernel_base = hdr->pref_address;
}
if (hdr->protocol_version >= 0x205) {
params.relocatable_kernel = hdr->relocatable_kernel;
params.kernel_alignment = hdr->kernel_alignment;
if (hdr->relocatable_kernel != 0) {
/* 16 MB should be way outside coreboot's playground,
* so if possible (relocatable kernel) use that to
* avoid a trampoline copy. */
kernel_base = ALIGN(16*1024*1024, params.kernel_alignment);
if (hdr->init_size == 0) {
ERROR("init_size 0 for relocatable kernel\n");
return -1;
}
}
}
/* We have a trampoline and use that, but it can simply use
* this information for its jump to real Linux. */
params.kernel_start = kernel_base;
if (bzp_add_kernel(&bzp, input, setup_size) != 0)
return -1;
if (buffer_size(&bzp.initrd) != 0) {
/* TODO: this is a bit of a hack. Linux recommends to store
* initrd near to end-of-mem, but that's hard to do on build
* time. It definitely fails to read the image if it's too
* close to the kernel, so give it some room.
*/
initrd_base = kernel_base + buffer_size(&bzp.kernel);
initrd_base = ALIGN(initrd_base, 64*1024*1024);
params.initrd_start = initrd_base;
params.initrd_size = buffer_size(&bzp.initrd);
}
if (bzp_add_params(&bzp, &params) != 0)
return -1;
if (bzp_init_output(&bzp, input->name) != 0)
return -1;
/* parameter block */
bzp_output_segment(&bzp, &bzp.parameters,
PAYLOAD_SEGMENT_DATA, LINUX_PARAM_LOC);
/* code block */
bzp_output_segment(&bzp, &bzp.kernel,
PAYLOAD_SEGMENT_CODE, kernel_base);
/* trampoline */
bzp_output_segment(&bzp, &bzp.trampoline,
PAYLOAD_SEGMENT_CODE, TRAMPOLINE_ENTRY_LOC);
/* cmdline */
bzp_output_segment(&bzp, &bzp.cmdline,
PAYLOAD_SEGMENT_DATA, COMMAND_LINE_LOC);
/* initrd */
bzp_output_segment(&bzp, &bzp.initrd,
PAYLOAD_SEGMENT_DATA, initrd_base);
/* Terminating entry segment. */
bzp_output_segment(&bzp, NULL, PAYLOAD_SEGMENT_ENTRY, TRAMPOLINE_ENTRY_LOC);
/* Set size of buffer taking into account potential compression. */
buffer_set_size(&bzp.output, bzp.offset);
/* Make passed-in output buffer be valid. */
buffer_clone(output, &bzp.output);
/* Serialize the segments with the correct encoding. */
xdr_segs(output, bzp.segs, bzp.num_segments);
return 0;
}