[PATCH] mtd: bcm47xxpart.c: Extra TRX magics, NVRAM part handling

[Jonas Gorski]

Hi,

On Sat, Jul 25, 2015 at 2:13 PM, Joseph East <eastyjr at gmail.com> wrote:
> A combination of four patches from the OpenWRT project:

It's written "OpenWrt" ;p

>
> 1) Add Xaiomi TRX signatures
> 2) Detect T-Meter partitions
> 3) Block reservation if NVRAM partition not found
> 4) Add Belkin TRX signatures (Play max series)

If it's based on four patches, it should be also submitted as four
patches, especially as these four changes only have in common that
they touch the same file.

>
> Based off of dev.openwrt.org repo @44854
>
> <trunk/target/linux/generic/patches-3.18>
> 431-mtd-bcm47xx.part-support-for-Xaiomi-specific-board_da.patch
> 432-mtd-bcm47xx.part-detect-T_Meter_partition_da.patch
>
> <trunk/target/linux/brcm47xx/patches-3.18>
> 400-mtd-bcm47xxpart-get-nvram.patch
>
> Signed-off-by: Joseph East <eastyjr at gmail.com>
> ---
>  drivers/mtd/bcm47xxpart.c | 45 +++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 43 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
> index c0720c1..aa9e425 100644
> --- a/drivers/mtd/bcm47xxpart.c
> +++ b/drivers/mtd/bcm47xxpart.c
> @@ -33,16 +33,22 @@
>  /* Magics */
>  #define BOARD_DATA_MAGIC               0x5246504D      /* MPFR */
>  #define BOARD_DATA_MAGIC2              0xBD0D0BBD
> +#define BOARD_DATA_XIAOMI_MAGIC        0x474D4442Q     /* GMDB */
>  #define CFE_MAGIC                      0x43464531      /* 1EFC */
>  #define FACTORY_MAGIC                  0x59544346      /* FCTY */
>  #define NVRAM_HEADER                   0x48534C46      /* FLSH */
>  #define POT_MAGIC1                     0x54544f50      /* POTT */
>  #define POT_MAGIC2                     0x504f          /* OP */
> +#define T_METER_MAGIC                  0x4D540000      /* MT */
>  #define ML_MAGIC1                      0x39685a42
>  #define ML_MAGIC2                      0x26594131
>  #define TRX_MAGIC                      0x30524448
>  #define SHSQ_MAGIC                     0x71736873      /* shsq (weird ZTE H218N endianness) */
>  #define UBI_EC_MAGIC                   0x23494255      /* UBI# */
> +#define BELKIN_F7D3301_MAGIC           0x20100322      /* Belkin TRX */
> +#define BELKIN_F7D3302_MAGIC           0x20090928
> +#define BELKIN_F7D4302_MAGIC           0x20101006
> +#define BELKIN_F7D4401_MAGIC           0x00018517
>
>  struct trx_header {
>         uint32_t magic;
> @@ -53,6 +59,19 @@ struct trx_header {
>         uint32_t offset[3];
>  } __packed;
>
> +static bool is_trx_magic(uint32_t magic) {
> +       switch (magic) {
> +       case TRX_MAGIC:
> +       case BELKIN_F7D3301_MAGIC:
> +       case BELKIN_F7D3302_MAGIC:
> +       case BELKIN_F7D4302_MAGIC:
> +       case BELKIN_F7D4401_MAGIC:
> +               return true;
> +       default:
> +               return false;
> +       }
> +}
> +
>  static void bcm47xxpart_add_part(struct mtd_partition *part, const char *name,
>                                  u64 offset, uint32_t mask_flags)
>  {
> @@ -95,6 +114,7 @@ static int bcm47xxpart_parse(struct mtd_info *master,
>         int trx_part = -1;
>         int last_trx_part = -1;
>         int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
> +       bool found_nvram = false;
>
>         /*
>          * Some really old flashes (like AT45DB*) had smaller erasesize-s, but
> @@ -176,8 +196,17 @@ static int bcm47xxpart_parse(struct mtd_info *master,
>                         continue;
>                 }
>
> +               /* T_Meter */
> +               if ((le32_to_cpu(buf[0x000 / 4]) & 0xFFFF0000) == T_METER_MAGIC &&
> +                   (le32_to_cpu(buf[0x030 / 4]) & 0xFFFF0000) == T_METER_MAGIC &&
> +                   (le32_to_cpu(buf[0x060 / 4]) & 0xFFFF0000) == T_METER_MAGIC) {
> +                       bcm47xxpart_add_part(&parts[curr_part++], "T_Meter", offset,
> +                                            MTD_WRITEABLE);
> +                       continue;
> +               }
> +
>                 /* TRX */
> -               if (buf[0x000 / 4] == TRX_MAGIC) {
> +               if (is_trx_magic(buf[0x000 / 4])) {
>                         if (BCM47XXPART_MAX_PARTS - curr_part < 4) {
>                                 pr_warn("Not enough partitions left to register trx, scanning stopped!\n");
>                                 break;
> @@ -262,7 +291,8 @@ static int bcm47xxpart_parse(struct mtd_info *master,
>                 }
>
>                 /* Some devices (ex. WNDR3700v3) don't have a standard 'MPFR' */
> -               if (buf[0x000 / 4] == BOARD_DATA_MAGIC2) {
> +               if (buf[0x000 / 4] == BOARD_DATA_MAGIC2 ||
> +                   le32_to_cpu(buf[0x000 / 4]) == BOARD_DATA_XIAOMI_MAGIC) {
>                         bcm47xxpart_add_part(&parts[curr_part++], "board_data",
>                                              offset, MTD_WRITEABLE);
>                         continue;
> @@ -288,12 +318,23 @@ static int bcm47xxpart_parse(struct mtd_info *master,
>                 if (buf[0] == NVRAM_HEADER) {
>                         bcm47xxpart_add_part(&parts[curr_part++], "nvram",
>                                              master->size - blocksize, 0);
> +                       found_nvram = true;
>                         break;
>                 }
>         }
>
>         kfree(buf);
>
> +       if (!found_nvram) {
> +               pr_err("can not find a nvram partition reserve last block\n");

I have trouble parsing this sentence, do you mean somethign like
"Cannot find an nvram partition, therefore reserve the last block as
one."? Also this probably should be a pr_warn, not a pr_err, as you
don't abort here.


> +               bcm47xxpart_add_part(&parts[curr_part++], "nvram_guess",
> +                                    master->size - blocksize * 2, MTD_WRITEABLE);
> +               for (i = 0; i < curr_part; i++) {
> +                       if (parts[i].size + parts[i].offset == master->size)
> +                               parts[i].offset -= blocksize * 2;

... and you reserve the last *two* blocks here, not just the last block.

> +               }
> +       }
> +
>         /*
>          * Assume that partitions end at the beginning of the one they are
>          * followed by.


Regards
Jonas