[PATCH V2 2/4] mtd: nand: mxs_nand_spl: Fix bad block skipping
Michael Nazzareno Trimarchi
michael at amarulasolutions.com
Sun May 1 08:36:15 CEST 2022
Dear Han and Fabio
On Thu, Apr 28, 2022 at 7:01 AM Michael Nazzareno Trimarchi
<michael at amarulasolutions.com> wrote:
>
> Hi
>
> On Thu, Apr 28, 2022 at 2:27 AM Han Xu <han.xu at nxp.com> wrote:
> >
> >
> >
> > > -----Original Message-----
> > > From: Michael Trimarchi <michael at amarulasolutions.com>
> > > Sent: Wednesday, April 27, 2022 12:50 AM
> > > To: Han Xu <han.xu at nxp.com>; U-Boot-Denx <u-boot at lists.denx.de>
> > > Cc: Ye Li <ye.li at nxp.com>; Stefano Babic <sbabic at denx.de>; Miquel Raynal
> > > <miquel.raynal at bootlin.com>; Fabio Estevam <festevam at denx.de>; Dario
> > > Binacchi <dario.binacchi at amarulasolutions.com>; Sean Anderson
> > > <sean.anderson at seco.com>; linux-kernel at amarulasolutions.com; Jagan Teki
> > > <jagan at amarulasolutions.com>; Ariel D'Alessandro
> > > <ariel.dalessandro at collabora.com>; Fabio Estevam <festevam at gmail.com>
> > > Subject: [PATCH V2 2/4] mtd: nand: mxs_nand_spl: Fix bad block skipping
> > >
> > > The specific implementation was having bug. Those bugs are since the beginning
> > > of the implementation. Some manufactures can receive this bug in their SPL code.
> > > This bug start to be more visible on architecture that has complicated boot
> > > process like imx8mn. Older version of uboot has the same problem only if the
> > > bad block appear in correspoding of befine of u-boot image. In order to adjust
> > > the function we scan from the first block. The logic is not changed to have a
> > > simple way to fix without get regression.
> > >
> > > The problematic part of old code was in this part:
> > >
> > > while (is_badblock(mtd, offs, 1)) {
> > > page = page + nand_page_per_block;
> > > /* Check i we've reached the end of flash. */
> > > if (page >= mtd->size >> chip->page_shift) {
> > > free(page_buf);
> > > return -ENOMEM;
> > > }
> > > }
> > >
> > > Even we fix it adding increment of the offset of one erase block size we don't fix
> > > the problem, because the first erase block where the image start is not checked.
> >
> > Could you please describe more details about your test? Thanks.
>
> Suppose you have a badblock on 5 or 6. Let's start to have only 6
> and you write uboot from 5 and let's the uboot be enough big to cover 5, 6, 7, 8
>
>
> Case 1)
> When you write the block 6 the code will skip it as bad during
> programming. THe image of uboot (or flash.bin) will
> be on 5 7 8 9, because the 6 is skipped. The while loop on spl will
> read (from raw offset the 5) and then he will found the
> bad block on next erase block in the while loop and will exists at the
> end of the flash because the test
> is done on the offset and not on the page that is not incremented
>
> Case 2)
>
> Now same example but let's suppose to have block 5 bad. So you write
> your image and it will start
> from a raw offset 5 but it will be written starting from 6. The spl
> loader will fail because it will not skip
> the first block and then will fail anyway to read the image. The patch
> try to fix the above behavior
>
> Case 3) can be any combination
>
Do I need to resend v3?
Michael
> Michael
>
>
>
> >
> > > The code was tested on an imx8mn where the boot rom api was not able to skip
> > > it. Apart of that other architecure are using this code and all boards that has
> > > nand as boot device can be affected
> > >
> > > Cc: Han Xu <han.xu at nxp.com>
> > > Cc: Fabio Estevam <festevam at gmail.com>
> > > Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
> > > ---
> > > V1->V2:
> > > - Adjust the commit message
> > > - Add Cc Han Xu and Fabio
> > > - fix size >= 0 to > 0
> > > ---
> > > drivers/mtd/nand/raw/mxs_nand_spl.c | 90 ++++++++++++++++-------------
> > > 1 file changed, 49 insertions(+), 41 deletions(-)
> > >
> > > diff --git a/drivers/mtd/nand/raw/mxs_nand_spl.c
> > > b/drivers/mtd/nand/raw/mxs_nand_spl.c
> > > index 59a67ee414..2bfb181007 100644
> > > --- a/drivers/mtd/nand/raw/mxs_nand_spl.c
> > > +++ b/drivers/mtd/nand/raw/mxs_nand_spl.c
> > > @@ -218,14 +218,14 @@ void nand_init(void)
> > > mxs_nand_setup_ecc(mtd);
> > > }
> > >
> > > -int nand_spl_load_image(uint32_t offs, unsigned int size, void *buf)
> > > +int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
> > > {
> > > - struct nand_chip *chip;
> > > - unsigned int page;
> > > + unsigned int sz;
> > > + unsigned int block, lastblock;
> > > + unsigned int page, page_offset;
> > > unsigned int nand_page_per_block;
> > > - unsigned int sz = 0;
> > > + struct nand_chip *chip;
> > > u8 *page_buf = NULL;
> > > - u32 page_off;
> > >
> > > chip = mtd_to_nand(mtd);
> > > if (!chip->numchips)
> > > @@ -235,47 +235,42 @@ int nand_spl_load_image(uint32_t offs, unsigned int
> > > size, void *buf)
> > > if (!page_buf)
> > > return -ENOMEM;
> > >
> > > - page = offs >> chip->page_shift;
> > > - page_off = offs & (mtd->writesize - 1);
> > > + /* offs has to be aligned to a page address! */
> > > + block = offs / mtd->erasesize;
> > > + lastblock = (offs + size - 1) / mtd->erasesize;
> > > + page = (offs % mtd->erasesize) / mtd->writesize;
> > > + page_offset = offs % mtd->writesize;
> > > nand_page_per_block = mtd->e
> Copy Link
> MA
> Copy Link
> NA
> Copy Link
> rasesize / mtd->writesize;
> > >
> > > - debug("%s offset:0x%08x len:%d page:%x\n", __func__, offs, size, page);
> > > -
> > > - while (size) {
> > > - if (mxs_read_page_ecc(mtd, page_buf, page) < 0)
> > > - return -1;
> > > -
> > > - if (size > (mtd->writesize - page_off))
> > > - sz = (mtd->writesize - page_off);
> > > - else
> > > - sz = size;
> > > -
> > > - memcpy(buf, page_buf + page_off, sz);
> > > -
> > > - offs += mtd->writesize;
> > > - page++;
> > > - buf += (mtd->writesize - page_off);
> > > - page_off = 0;
> > > - size -= sz;
> > > -
> > > - /*
> > > - * Check if we have crossed a block boundary, and if so
> > > - * check for bad block.
> > > - */
> > > - if (!(page % nand_page_per_block)) {
> > > - /*
> > > - * Yes, new block. See if this block is good. If not,
> > > - * loop until we find a good block.
> > > - */
> > > - while (is_badblock(mtd, offs, 1)) {
> > > - page = page + nand_page_per_block;
> > > - /* Check i we've reached the end of flash. */
> > > - if (page >= mtd->size >> chip->page_shift) {
> > > + while (block <= lastblock && size > 0) {
> > > + if (!is_badblock(mtd, mtd->erasesize * block, 1)) {
> > > + /* Skip bad blocks */
> > > + while (page < nand_page_per_block) {
> > > + int curr_page = nand_page_per_block * block +
> > > page;
> > > +
> > > + if (mxs_read_page_ecc(mtd, page_buf, curr_page)
> > > < 0) {
> > > free(page_buf);
> > > - return -ENOMEM;
> > > + return -EIO;
> > > }
> > > +
> > > + if (size > (mtd->writesize - page_offset))
> > > + sz = (mtd->writesize - page_offset);
> > > + else
> > > + sz = size;
> > > +
> > > + memcpy(dst, page_buf + page_offset, sz);
> > > + dst += sz;
> > > + size -= sz;
> > > + page_offset = 0;
> > > + page++;
> > > }
> > > +
> > > + page = 0;
> > > + } else {
> > > + lastblock++;
> > > }
> > > +
> > > + block++;
> > > }
> > >
> > > free(page_buf);
> > > @@ -294,6 +289,19 @@ void nand_deselect(void)
> > >
> > > u32 nand_spl_adjust_offset(u32 sector, u32 offs) {
> > > - /* Handle the offset adjust in nand_spl_load_image,*/
> > > + unsigned int block, lastblock;
> > > +
> > > + block = sector / mtd->erasesize;
> > > + lastblock = (sector + offs) / mtd->erasesize;
> > > +
> > > + while (block <= lastblock) {
> > > + if (is_badblock(mtd, block * mtd->erasesize, 1)) {
> > > + offs += mtd->erasesize;
> > > + lastblock++;
> > > + }
> > > +
> > > + block++;
> > > + }
> > > +
> > > return offs;
> > > }
> > > --
> > > 2.25.1
> >
>
>
> --
> Michael Nazzareno Trimarchi
> Co-Founder & Chief Executive Officer
> M. +39 347 913 2170
> michael at amarulasolutions.com
> __________________________________
>
> Amarula Solutions BV
> Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
> T. +31 (0)85 111 9172
> info at amarulasolutions.com
> www.amarulasolutions.com
--
Michael Nazzareno Trimarchi
Co-Founder & Chief Executive Officer
M. +39 347 913 2170
michael at amarulasolutions.com
__________________________________
Amarula Solutions BV
Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
T. +31 (0)85 111 9172
info at amarulasolutions.com
www.amarulasolutions.com
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