spl: add squashfs support

Implement spl_load_image_sqfs() in spl code.

This will be used in MMC to read a file from a squashfs partition.

Also, loosen squashfs read checks on file size by not failing when a
bigger size than the actual file size is requested. (Just read the file)
This is needed for FIT loading, because the length is ALIGNed.

Signed-off-by: Richard Genoud <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Reviewed-by: João Marcos Costa <[email protected]>

2 files changed, 79 insertions, 0 deletions

diff --git a/common/spl/Makefile b/common/spl/Makefile
index 4c9482bd309..53cc45fc5b9 100644
--- a/common/spl/Makefile
+++ b/common/spl/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_$(PHASE_)OPENSBI) += spl_opensbi.o
 obj-$(CONFIG_$(PHASE_)USB_STORAGE) += spl_usb.o
 obj-$(CONFIG_$(PHASE_)FS_FAT) += spl_fat.o
 obj-$(CONFIG_$(PHASE_)FS_EXT4) += spl_ext.o
+obj-$(CONFIG_$(PHASE_)FS_SQUASHFS) += spl_squashfs.o
 obj-$(CONFIG_$(PHASE_)LOAD_IMX_CONTAINER) += spl_imx_container.o
 obj-$(CONFIG_$(PHASE_)SATA) += spl_sata.o
 obj-$(CONFIG_$(PHASE_)NVME) += spl_nvme.o
diff --git a/common/spl/spl_squashfs.c b/common/spl/spl_squashfs.c
new file mode 100644
index 00000000000..d3b1c70bfc4
--- /dev/null
+++ b/common/spl/spl_squashfs.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 Paratronic
+ * Copyright (C) 2026 Bootlin
+ *
+ * Author: Richard Genoud <[email protected]>
+ *
+ */
+
+#include <env.h>
+#include <part.h>
+#include <spl.h>
+#include <spl_load.h>
+#include <squashfs.h>
+#include <errno.h>
+#include <image.h>
+
+static ulong spl_fit_read(struct spl_load_info *load, ulong file_offset,
+			  ulong size, void *buf)
+{
+	struct legacy_img_hdr *header;
+	char *filename = load->priv;
+	loff_t actread;
+	int ret;
+
+	ret = sqfs_read(filename, buf, file_offset, size, &actread);
+	if (ret)
+		return ret;
+
+	if (CONFIG_IS_ENABLED(OS_BOOT)) {
+		header = (struct legacy_img_hdr *)buf;
+		if (image_get_magic(header) != FDT_MAGIC)
+			return size;
+	}
+
+	return actread;
+}
+
+int spl_load_image_sqfs(struct spl_image_info *spl_image,
+			struct spl_boot_device *bootdev,
+			struct blk_desc *block_dev, int partition,
+			const char *filename)
+{
+	int err;
+	loff_t size = 0;
+	struct spl_load_info load;
+	struct disk_partition part_info = {};
+
+	err = part_get_info(block_dev, partition, &part_info);
+	if (err) {
+		printf("spl: no partition table found\n");
+		goto end;
+	}
+
+	err = sqfs_probe(block_dev, &part_info);
+	if (err) {
+		printf("spl: sqfs probe err part_name:%s type=%s err=%d\n",
+		       part_info.name, part_info.type, err);
+		goto end;
+	}
+
+	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT_FULL)) {
+		err = sqfs_size(filename, &size);
+		if (err)
+			goto end;
+	}
+
+	spl_load_init(&load, spl_fit_read, (void *)filename, 1);
+
+	err = spl_load(spl_image, bootdev, &load, size, 0);
+
+end:
+	if (err < 0)
+		printf("%s: error reading image %s, err - %d\n",
+		       __func__, filename, err);
+
+	return err;
+}