bootstd: cros: Decode some kernel preamble fields

Decode the kernel start and size using the structures provided. This
accesses the same data, just in a cleaner way.

Add some logging for some of the fields in the kernel preamble.

Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass
2023-07-30 11:16:51 -06:00
parent 4cfe4510f1
commit 3257835e56

View File

@@ -27,10 +27,6 @@
enum {
PROBE_SIZE = SZ_4K, /* initial bytes read from partition */
/* Offsets in the kernel-partition header */
KERN_START = 0x4f0,
KERN_SIZE = 0x518,
SETUP_OFFSET = 0x1000, /* bytes before base */
CMDLINE_OFFSET = 0x2000, /* bytes before base */
OFFSET_BASE = 0x100000, /* assumed kernel load-address */
@@ -93,7 +89,7 @@ static int copy_cmdline(const char *from, const char *uuid, char **bufp)
* @hdrp: Return allocated keyblock header on success
*/
static int scan_part(struct udevice *blk, int partnum,
struct disk_partition *info, void **hdrp)
struct disk_partition *info, struct vb2_keyblock **hdrp)
{
struct blk_desc *desc = dev_get_uclass_plat(blk);
struct vb2_keyblock *hdr;
@@ -130,11 +126,14 @@ static int scan_part(struct udevice *blk, int partnum,
static int cros_read_bootflow(struct udevice *dev, struct bootflow *bflow)
{
struct blk_desc *desc = dev_get_uclass_plat(bflow->blk);
ulong base, start, size, setup, cmdline, num_blks, kern_base;
ulong base, start, setup, cmdline, num_blks, kern_base;
const struct vb2_kernel_preamble *preamble;
ulong body_offset, body_size;
struct disk_partition info;
const char *uuid = NULL;
void *buf, *hdr;
struct vb2_keyblock *hdr;
int part, ret;
void *buf;
log_debug("starting, part=%d\n", bflow->part);
@@ -155,18 +154,39 @@ static int cros_read_bootflow(struct udevice *dev, struct bootflow *bflow)
log_info("Selected parition %d, header at %lx\n", bflow->part,
(ulong)map_to_sysmem(hdr));
start = *(u32 *)(hdr + KERN_START);
size = ALIGN(*(u32 *)(hdr + KERN_SIZE), desc->blksz);
log_debug("Reading start %lx size %lx\n", start, size);
bflow->size = size;
preamble = (void *)hdr + hdr->keyblock_size;
log_debug("Kernel preamble at %lx, version major %x, minor %x\n",
(ulong)map_to_sysmem(preamble),
preamble->header_version_major,
preamble->header_version_minor);
buf = memalign(SZ_1K, size);
start = (ulong)preamble->bootloader_address;
log_debug(" - load_address %lx, bl_addr %lx, bl_size %lx\n",
(ulong)preamble->body_load_address,
(ulong)preamble->bootloader_address,
(ulong)preamble->bootloader_size);
body_offset = hdr->keyblock_size + preamble->preamble_size;
body_size = preamble->body_signature.data_size;
log_debug("Kernel body at %lx size %lx\n", body_offset, body_size);
bflow->size = body_size;
buf = memalign(SZ_1K, body_size);
if (!buf)
return log_msg_ret("buf", -ENOMEM);
num_blks = size >> desc->log2blksz;
log_debug("Reading data, blk=%s, start=%lx, blocks=%lx\n",
bflow->blk->name, (ulong)info.start, num_blks);
ret = blk_read(bflow->blk, (ulong)info.start + 0x80, num_blks, buf);
/* Check that the header is not smaller than permitted */
if (body_offset < PROBE_SIZE)
return log_msg_ret("san", EFAULT);
/* Read kernel body */
num_blks = body_size >> desc->log2blksz;
log_debug("Reading body to %lx, blk=%s, size=%lx, blocks=%lx\n",
(ulong)map_to_sysmem(buf), bflow->blk->name, body_size,
num_blks);
ret = blk_read(bflow->blk,
info.start + (body_offset >> desc->log2blksz),
num_blks, buf);
if (ret != num_blks)
return log_msg_ret("inf", -EIO);
base = map_to_sysmem(buf);