Hi Miquel On Tue, Nov 28, 2023 at 11:56 AM Miquel Raynal <[email protected]> wrote: > > This is a debug command to monitor the retention state of the data on > the array. The command needs a duplication of the mtd_read_oob() > function to actually return the maximum number of bitflips encountered > while reading the page. We could write a specific implementation for the > Sunxi driver but this is probably enough. > > nand watch <off> <size> - check an area for bitflips > nand watch.part <part> - check a partition for bitflips > nand watch.chip - check the whole device for bitflips > > The output may be a bit verbose and could look like: >
I have rebased and I will take a look on this patch tomorrow. I think having it is ok. Michael > => nand watch.chip > device 0 whole chip > size adjusted to 0xff60000 (5 bad blocks) > > NAND watch for bitflips in area 0x0-0xff60000: > Page 0 (0x00000000) -> error -74 > Page 1 (0x00000800) -> error -74 > Page 2 (0x00001000) -> error -74 > Page 3 (0x00001800) -> error -74 > Page 4 (0x00002000) -> error -74 > Page 5 (0x00002800) -> error -74 > Page 6 (0x00003000) -> error -74 > Page 7 (0x00003800) -> error -74 > Page 8 (0x00004000) -> error -74 > Page 9 (0x00004800) -> error -74 > Page 10 (0x00005000) -> error -74 > Page 11 (0x00005800) -> error -74 > Page 12 (0x00006000) -> error -74 > Page 13 (0x00006800) -> error -74 > Page 14 (0x00007000) -> error -74 > Page 15 (0x00007800) -> error -74 > Page 16 (0x00008000) -> error -74 > Page 17 (0x00008800) -> error -74 > Page 18 (0x00009000) -> error -74 > Page 19 (0x00009800) -> error -74 > Page 20 (0x0000a000) -> error -74 > Page 21 (0x0000a800) -> error -74 > Page 22 (0x0000b000) -> error -74 > Page 23 (0x0000b800) -> error -74 > Page 1110 (0x0022b000) -> up to 1 bf/chunk > Page 1122 (0x00231000) -> up to 1 bf/chunk > Page 1132 (0x00236000) -> up to 1 bf/chunk > Page 1362 (0x002a9000) -> up to 1 bf/chunk > Page 4990 (0x009bf000) -> up to 1 bf/chunk > Page 5728 (0x00b30000) -> up to 1 bf/chunk > Page 7116 (0x00de6000) -> up to 1 bf/chunk > Page 7160 (0x00dfc000) -> up to 1 bf/chunk > Page 7494 (0x00ea3000) -> up to 1 bf/chunk > Page 10842 (0x0152d000) -> up to 1 bf/chunk > Page 11614 (0x016af000) -> up to 1 bf/chunk > Page 11970 (0x01761000) -> up to 1 bf/chunk > Page 12536 (0x0187c000) -> up to 1 bf/chunk > Page 12687 (0x018c7800) -> up to 1 bf/chunk > Page 14298 (0x01bed000) -> up to 1 bf/chunk > Page 18268 (0x023ae000) -> up to 1 bf/chunk > Page 18760 (0x024a4000) -> up to 1 bf/chunk > Page 21440 (0x029e0000) -> up to 1 bf/chunk > Page 22336 (0x02ba0000) -> up to 1 bf/chunk > Page 22592 (0x02c20000) -> up to 1 bf/chunk > Page 23872 (0x02ea0000) -> up to 1 bf/chunk > Page 27584 (0x035e0000) -> up to 1 bf/chunk > Page 35008 (0x04460000) -> up to 1 bf/chunk > Page 37184 (0x048a0000) -> up to 1 bf/chunk > Page 41728 (0x05180000) -> up to 1 bf/chunk > Page 42176 (0x05260000) -> up to 1 bf/chunk > Page 43200 (0x05460000) -> up to 1 bf/chunk > Page 43328 (0x054a0000) -> up to 1 bf/chunk > Page 45376 (0x058a0000) -> up to 1 bf/chunk > Page 47040 (0x05be0000) -> up to 1 bf/chunk > Page 47552 (0x05ce0000) -> up to 1 bf/chunk > Page 49344 (0x06060000) -> up to 1 bf/chunk > Page 49856 (0x06160000) -> up to 1 bf/chunk > Page 62784 (0x07aa0000) -> up to 1 bf/chunk > Page 65153 (0x07f40800) -> up to 1 bf/chunk > Page 65228 (0x07f66000) -> up to 1 bf/chunk > Page 65382 (0x07fb3000) -> up to 1 bf/chunk > Page 98624 (0x0c0a0000) -> up to 1 bf/chunk > Page 101952 (0x0c720000) -> up to 1 bf/chunk > Page 107584 (0x0d220000) -> up to 1 bf/chunk > Page 118208 (0x0e6e0000) -> up to 1 bf/chunk > Page 126656 (0x0f760000) -> up to 1 bf/chunk > Page 127680 (0x0f960000) -> up to 1 bf/chunk > Page 129920 (0x0fdc0000) -> up to 1 bf/chunk > Maximum number of bitflips: 1 > Pages with bitflips: 44/130752 > > It is also possible to reduce the output with the .quiet suffix in order > to just show the summary. > > => nand watch.chip > device 0 whole chip > size adjusted to 0xff60000 (5 bad blocks) > > NAND watch for bitflips in area 0x0-0xff60000: > Maximum number of bitflips: 1 > Pages with bitflips: 44/130752 > > Signed-off-by: Miquel Raynal <[email protected]> > --- > > Hello, I recently came across a batch of NANDs with a lot of "natural" > bitflips so in order to easily and objectively characterize how > unstable these parts were, I wrote this little tool which was pretty > handy to have in U-Boot. I believe it can be useful for others as well, > so here is the patch. > Cheers, Miquèl > > cmd/Kconfig | 5 ++ > cmd/nand.c | 103 ++++++++++++++++++++++++++++++++++++++++ > drivers/mtd/mtdcore.c | 22 +++++++++ > include/linux/mtd/mtd.h | 1 + > 4 files changed, 131 insertions(+) > > diff --git a/cmd/Kconfig b/cmd/Kconfig > index 451baa3ecac..0524328d373 100644 > --- a/cmd/Kconfig > +++ b/cmd/Kconfig > @@ -1384,6 +1384,11 @@ config CMD_NAND_TORTURE > help > NAND torture support. > > +config CMD_NAND_WATCH > + bool "nand watch" > + help > + NAND watch bitflip support. > + > endif # CMD_NAND > > config CMD_NVME > diff --git a/cmd/nand.c b/cmd/nand.c > index 71b8f964429..3bf67f5b65e 100644 > --- a/cmd/nand.c > +++ b/cmd/nand.c > @@ -231,6 +231,54 @@ free_dat: > return ret; > } > > +#ifdef CONFIG_CMD_NAND_WATCH > +static int nand_watch_bf(struct mtd_info *mtd, ulong off, ulong size, bool > quiet) > +{ > + unsigned int max_bf = 0, pages_wbf = 0; > + unsigned int first_page, pages, i; > + struct mtd_oob_ops ops = {}; > + u_char *buf; > + int ret; > + > + buf = memalign(ARCH_DMA_MINALIGN, mtd->writesize); > + if (!buf) { > + puts("No memory for page buffer\n"); > + return 1; > + } > + > + first_page = off / mtd->writesize; > + pages = size / mtd->writesize; > + > + ops.datbuf = buf; > + ops.len = mtd->writesize; > + for (i = first_page; i < first_page + pages; i++) { > + ulong addr = mtd->writesize * i; > + ret = mtd_read_oob_bf(mtd, addr, &ops); > + if (ret < 0) { > + if (quiet) > + continue; > + > + printf("Page %7d (0x%08lx) -> error %d\n", > + i, addr, ret); > + } else if (ret) { > + max_bf = max(max_bf, (unsigned int)ret); > + pages_wbf++; > + if (quiet) > + continue; > + printf("Page %7d (0x%08lx) -> up to %2d bf/chunk\n", > + i, addr, ret); > + } > + } > + > + printf("Maximum number of bitflips: %u\n", max_bf); > + printf("Pages with bitflips: %u/%u\n", pages_wbf, pages); > + > + free(buf); > + > + return 0; > +} > +#endif > + > /* ------------------------------------------------------------------------- > */ > > static int set_dev(int dev) > @@ -778,6 +826,55 @@ static int do_nand(struct cmd_tbl *cmdtp, int flag, int > argc, > return ret == 0 ? 0 : 1; > } > > +#ifdef CONFIG_CMD_NAND_WATCH > + if (strncmp(cmd, "watch", 5) == 0) { > + int args = 2; > + > + if (cmd[5]) { > + if (!strncmp(&cmd[5], ".part", 5)) { > + args = 1; > + } else if (!strncmp(&cmd[5], ".chip", 5)) { > + args = 0; > + } else { > + goto usage; > + } > + } > + > + if (cmd[10]) > + if (!strncmp(&cmd[10], ".quiet", 6)) > + quiet = true; > + > + if (argc != 2 + args) > + goto usage; > + > + ret = mtd_arg_off_size(argc - 2, argv + 2, &dev, &off, &size, > + &maxsize, MTD_DEV_TYPE_NAND, > mtd->size); > + if (ret) > + return ret; > + > + /* size is unspecified */ > + if (argc < 4) > + adjust_size_for_badblocks(&size, off, dev); > + > + if ((off & (mtd->writesize - 1)) || > + (size & (mtd->writesize - 1))) { > + printf("Attempt to read non page-aligned data\n"); > + return -EINVAL; > + } > + > + ret = set_dev(dev); > + if (ret) > + return ret; > + > + mtd = get_nand_dev_by_index(dev); > + > + printf("\nNAND watch for bitflips in area 0x%llx-0x%llx:\n", > + off, off + size); > + > + return nand_watch_bf(mtd, off, size, quiet); > + } > +#endif > + > #ifdef CONFIG_CMD_NAND_TORTURE > if (strcmp(cmd, "torture") == 0) { > loff_t endoff; > @@ -943,6 +1040,12 @@ U_BOOT_LONGHELP(nand, > "nand erase.chip [clean] - erase entire chip'\n" > "nand bad - show bad blocks\n" > "nand dump[.oob] off - dump page\n" > +#ifdef CONFIG_CMD_NAND_WATCH > + "nand watch <off> <size> - check an area for bitflips\n" > + "nand watch.part <part> - check a partition for bitflips\n" > + "nand watch.chip - check the whole device for bitflips\n" > + "\t\t.quiet - Query only the summary, not the details\n" > +#endif > #ifdef CONFIG_CMD_NAND_TORTURE > "nand torture off - torture one block at offset\n" > "nand torture off [size] - torture blocks from off to off+size\n" > diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c > index aa78d41a55e..2baf92a9056 100644 > --- a/drivers/mtd/mtdcore.c > +++ b/drivers/mtd/mtdcore.c > @@ -1126,6 +1126,28 @@ int mtd_read_oob(struct mtd_info *mtd, loff_t from, > struct mtd_oob_ops *ops) > } > EXPORT_SYMBOL_GPL(mtd_read_oob); > > +/* This is a bare copy of mtd_read_oob returning the actual number of > bitflips */ > +int mtd_read_oob_bf(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops > *ops) > +{ > + int ret_code; > + ops->retlen = ops->oobretlen = 0; > + if (!mtd->_read_oob) > + return -EOPNOTSUPP; > + /* > + * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics > + * similar to mtd->_read(), returning a non-negative integer > + * representing max bitflips. In other cases, mtd->_read_oob() may > + * return -EUCLEAN. In all cases, perform similar logic to mtd_read(). > + */ > + ret_code = mtd->_read_oob(mtd, from, ops); > + if (unlikely(ret_code < 0)) > + return ret_code; > + if (mtd->ecc_strength == 0) > + return 0; /* device lacks ecc */ > + return ret_code; > +} > +EXPORT_SYMBOL_GPL(mtd_read_oob_bf); > + > int mtd_write_oob(struct mtd_info *mtd, loff_t to, > struct mtd_oob_ops *ops) > { > diff --git a/include/linux/mtd/mtd.h b/include/linux/mtd/mtd.h > index 09f52698877..28afbb86ea9 100644 > --- a/include/linux/mtd/mtd.h > +++ b/include/linux/mtd/mtd.h > @@ -413,6 +413,7 @@ int mtd_panic_write(struct mtd_info *mtd, loff_t to, > size_t len, size_t *retlen, > const u_char *buf); > > int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops); > +int mtd_read_oob_bf(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops > *ops); > int mtd_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops); > > int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen, > -- > 2.34.1 > -- Michael Nazzareno Trimarchi Co-Founder & Chief Executive Officer M. +39 347 913 2170 [email protected] __________________________________ Amarula Solutions BV Joop Geesinkweg 125, 1114 AB, Amsterdam, NL T. +31 (0)85 111 9172 [email protected] www.amarulasolutions.com
