1 files changed, 193 insertions, 0 deletions
diff --git a/boot/bootmeth_extlinux.c b/boot/bootmeth_extlinux.c
new file mode 100644
index 0000000000..24be076022
--- /dev/null
+++ b/boot/bootmeth_extlinux.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Bootmethod for extlinux 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 <dm.h>
+#include <extlinux.h>
+#include <fs.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <mmc.h>
+#include <pxe_utils.h>
+
+static int extlinux_get_state_desc(struct udevice *dev, char *buf, int maxsize)
+{
+	if (IS_ENABLED(CONFIG_SANDBOX)) {
+		int len;
+
+		len = snprintf(buf, maxsize, "OK");
+
+		return len + 1 < maxsize ? 0 : -ENOSPC;
+	}
+
+	return 0;
+}
+
+static int extlinux_getfile(struct pxe_context *ctx, const char *file_path,
+			    char *file_addr, ulong *sizep)
+{
+	struct extlinux_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 extlinux_check(struct udevice *dev, struct bootflow_iter *iter)
+{
+	int ret;
+
+	/* This only works on block devices */
+	ret = bootflow_iter_check_blk(iter);
+	if (ret)
+		return log_msg_ret("blk", ret);
+
+	return 0;
+}
+
+/**
+ * extlinux_fill_info() - Decode the extlinux file to find out its info
+ *
+ * @bflow: Bootflow to process
+ * @return 0 if OK, -ve on error
+ */
+static int extlinux_fill_info(struct bootflow *bflow)
+{
+	struct membuff mb;
+	char line[200];
+	char *data;
+	int len;
+
+	log_debug("parsing bflow file size %x\n", bflow->size);
+	membuff_init(&mb, bflow->buf, bflow->size);
+	membuff_putraw(&mb, bflow->size, true, &data);
+	while (len = membuff_readline(&mb, line, sizeof(line) - 1, ' '), len) {
+		char *tok, *p = line;
+
+		tok = strsep(&p, " ");
+		if (p) {
+			if (!strcmp("label", tok)) {
+				bflow->os_name = strdup(p);
+				if (!bflow->os_name)
+					return log_msg_ret("os", -ENOMEM);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int extlinux_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, EXTLINUX_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);
+
+	ret = extlinux_fill_info(bflow);
+	if (ret)
+		return log_msg_ret("inf", ret);
+
+	return 0;
+}
+
+static int extlinux_boot(struct udevice *dev, struct bootflow *bflow)
+{
+	struct cmd_tbl cmdtp = {};	/* dummy */
+	struct pxe_context ctx;
+	struct extlinux_info info;
+	ulong addr;
+	int ret;
+
+	addr = map_to_sysmem(bflow->buf);
+	info.dev = dev;
+	info.bflow = bflow;
+	ret = pxe_setup_ctx(&ctx, &cmdtp, extlinux_getfile, &info, true,
+			    bflow->subdir, false);
+	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 extlinux_bootmeth_bind(struct udevice *dev)
+{
+	struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
+
+	plat->desc = IS_ENABLED(CONFIG_BOOTSTD_FULL) ?
+		"Extlinux boot from a block device" : "extlinux";
+
+	return 0;
+}
+
+static struct bootmeth_ops extlinux_bootmeth_ops = {
+	.get_state_desc	= extlinux_get_state_desc,
+	.check		= extlinux_check,
+	.read_bootflow	= extlinux_read_bootflow,
+	.read_file	= bootmeth_common_read_file,
+	.boot		= extlinux_boot,
+};
+
+static const struct udevice_id extlinux_bootmeth_ids[] = {
+	{ .compatible = "u-boot,extlinux" },
+	{ }
+};
+
+U_BOOT_DRIVER(bootmeth_extlinux) = {
+	.name		= "bootmeth_extlinux",
+	.id		= UCLASS_BOOTMETH,
+	.of_match	= extlinux_bootmeth_ids,
+	.ops		= &extlinux_bootmeth_ops,
+	.bind		= extlinux_bootmeth_bind,
+};