spl: nand: Set bl_len to page size

Since commit 34793598c83 ("mtd: nand: mxs_nand_spl: Remove the page aligned
access") there are no longer any users of nand_get_mtd. However, it is
still important to know what the page size is so we can allocate a
large-enough buffer. If the image size is not page-aligned, we will go off
the end of the buffer and clobber some memory.

Introduce a new function nand_page_size which returns the page size. For
most drivers it is easy to determine the page size. However, a few need to
be modified since they only keep the page size around temporarily.

It's possible that this patch could cause a regression on some platforms if
the offset is non-aligned and there is invalid address space immediately
before the load address. spl_load_legacy_img does not (except when
compressing) respect bl_len, so only boards with SPL_LOAD_FIT (8 boards) or
SPL_LOAD_IMX_CONTAINER (none in tree) would be affected.

defconfig               CONFIG_TEXT_BASE
======================= ================
am335x_evm              0x80800000
am43xx_evm              0x80800000
am43xx_evm_rtconly      0x80800000
am43xx_evm_usbhost_boot 0x80800000
am43xx_hs_evm           0x80800000
dra7xx_evm              0x80800000
gwventana_nand          0x17800000
imx8mn_bsh_smm_s2       0x40200000

All the sitara boards have DDR mapped at 0x80000000. gwventana is an i.MX6Q
which has DDR at 0x10000000. I don't have the IMX8MNRM handy, but on the
i.MX8M DDR starts at 0x40000000. Therefore all of these boards can handle a
little underflow.

Signed-off-by: Sean Anderson <seanga2@gmail.com>

1 files changed, 3 insertions, 8 deletions

diff --git a/common/spl/spl_nand.c b/common/spl/spl_nand.c
index 5b6932bf7e0..57a7a1a73b9 100644
--- a/common/spl/spl_nand.c
+++ b/common/spl/spl_nand.c
@@ -72,23 +72,18 @@ static ulong spl_nand_legacy_read(struct spl_load_info *load, ulong offs,
 	return size;
 }
 
-struct mtd_info * __weak nand_get_mtd(void)
-{
-	return NULL;
-}
-
 static int spl_nand_load_element(struct spl_image_info *spl_image,
 				 struct spl_boot_device *bootdev,
 				 int offset, struct legacy_img_hdr *header)
 {
-	struct mtd_info *mtd = nand_get_mtd();
-	int bl_len = mtd ? mtd->writesize : 1;
+	int bl_len;
 	int err;
 
 	err = nand_spl_load_image(offset, sizeof(*header), (void *)header);
 	if (err)
 		return err;
 
+	bl_len = nand_page_size();
 	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
 	    image_get_magic(header) == FDT_MAGIC) {
 		struct spl_load_info load;
@@ -118,7 +113,7 @@ static int spl_nand_load_element(struct spl_image_info *spl_image,
 		load.dev = NULL;
 		load.priv = NULL;
 		load.filename = NULL;
-		load.bl_len = 1;
+		load.bl_len = IS_ENABLED(CONFIG_SPL_LZMA) ? bl_len : 1;
 		load.read = spl_nand_legacy_read;
 
 		return spl_load_legacy_img(spl_image, bootdev, &load, offset, header);