u-boot/boot/bootmeth_distro.c
Simon Glass 31aefaf89a bootstd: Add an implementation of distro boot
Add a bootmeth driver which handles distro boot from a disk, so we can
boot a bootflow using this commonly used mechanism.

In effect, this provides the same functionality as the 'sysboot' command
and shares the same code. But the interface into it is via a bootmeth.

For now this requires the 'pxe' command be enabled. Future work may tidy
this up so that it can be used without CONFIG_CMDLINE being enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
2022-04-25 10:00:04 -04:00

143 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Bootmethod for distro boot (syslinux boot from a block device)
*
* Copyright 2021 Google LLC
* Written by Simon Glass <sjg@chromium.org>
*/
#define LOG_CATEGORY UCLASS_BOOTSTD
#include <common.h>
#include <bootdev.h>
#include <bootflow.h>
#include <bootmeth.h>
#include <bootstd.h>
#include <command.h>
#include <distro.h>
#include <dm.h>
#include <fs.h>
#include <malloc.h>
#include <mapmem.h>
#include <mmc.h>
#include <pxe_utils.h>
static int disto_getfile(struct pxe_context *ctx, const char *file_path,
char *file_addr, ulong *sizep)
{
struct distro_info *info = ctx->userdata;
ulong addr;
int ret;
addr = simple_strtoul(file_addr, NULL, 16);
/* Allow up to 1GB */
*sizep = 1 << 30;
ret = bootmeth_read_file(info->dev, info->bflow, file_path, addr,
sizep);
if (ret)
return log_msg_ret("read", ret);
return 0;
}
static int distro_check(struct udevice *dev, struct bootflow_iter *iter)
{
int ret;
/* This only works on block devices */
ret = bootflow_iter_uses_blk_dev(iter);
if (ret)
return log_msg_ret("blk", ret);
return 0;
}
static int distro_read_bootflow(struct udevice *dev, struct bootflow *bflow)
{
struct blk_desc *desc;
const char *const *prefixes;
struct udevice *bootstd;
const char *prefix;
loff_t size;
int ret, i;
ret = uclass_first_device_err(UCLASS_BOOTSTD, &bootstd);
if (ret)
return log_msg_ret("std", ret);
/* If a block device, we require a partition table */
if (bflow->blk && !bflow->part)
return -ENOENT;
prefixes = bootstd_get_prefixes(bootstd);
i = 0;
desc = bflow->blk ? dev_get_uclass_plat(bflow->blk) : NULL;
do {
prefix = prefixes ? prefixes[i] : NULL;
ret = bootmeth_try_file(bflow, desc, prefix, DISTRO_FNAME);
} while (ret && prefixes && prefixes[++i]);
if (ret)
return log_msg_ret("try", ret);
size = bflow->size;
ret = bootmeth_alloc_file(bflow, 0x10000, 1);
if (ret)
return log_msg_ret("read", ret);
return 0;
}
static int distro_boot(struct udevice *dev, struct bootflow *bflow)
{
struct cmd_tbl cmdtp = {}; /* dummy */
struct pxe_context ctx;
struct distro_info info;
ulong addr;
int ret;
addr = map_to_sysmem(bflow->buf);
info.dev = dev;
info.bflow = bflow;
ret = pxe_setup_ctx(&ctx, &cmdtp, disto_getfile, &info, true,
bflow->subdir);
if (ret)
return log_msg_ret("ctx", -EINVAL);
ret = pxe_process(&ctx, addr, false);
if (ret)
return log_msg_ret("bread", -EINVAL);
return 0;
}
static int distro_bootmeth_bind(struct udevice *dev)
{
struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
plat->desc = IS_ENABLED(CONFIG_BOOTSTD_FULL) ?
"Syslinux boot from a block device" : "syslinux";
return 0;
}
static struct bootmeth_ops distro_bootmeth_ops = {
.check = distro_check,
.read_bootflow = distro_read_bootflow,
.read_file = bootmeth_common_read_file,
.boot = distro_boot,
};
static const struct udevice_id distro_bootmeth_ids[] = {
{ .compatible = "u-boot,distro-syslinux" },
{ }
};
U_BOOT_DRIVER(bootmeth_distro) = {
.name = "bootmeth_distro",
.id = UCLASS_BOOTMETH,
.of_match = distro_bootmeth_ids,
.ops = &distro_bootmeth_ops,
.bind = distro_bootmeth_bind,
};