RE: [PATCH v3 1/2] mtd: spi-nor: add support to non-uniform SFDP SPI NOR flash memories

From: Yogesh Narayan Gaur
Date: Mon Oct 22 2018 - 02:04:29 EST


Hi Boris, Tudor,

> -----Original Message-----
> From: Boris Brezillon [mailto:boris.brezillon@xxxxxxxxxxx]
> Sent: Wednesday, October 17, 2018 3:23 PM
> To: Yogesh Narayan Gaur <yogeshnarayan.gaur@xxxxxxx>
> Cc: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxx>; Tudor Ambarus
> <tudor.ambarus@xxxxxxxxxxxxx>; marek.vasut@xxxxxxxxx;
> dwmw2@xxxxxxxxxxxxx; computersforpeace@xxxxxxxxx; richard@xxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; nicolas.ferre@xxxxxxxxxxxxx;
> cyrille.pitchen@xxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; Cristian.Birsan@xxxxxxxxxxxxx
> Subject: Re: [PATCH v3 1/2] mtd: spi-nor: add support to non-uniform SFDP SPI
> NOR flash memories
>
> On Wed, 17 Oct 2018 07:46:30 +0000
> Yogesh Narayan Gaur <yogeshnarayan.gaur@xxxxxxx> wrote:
>
> > Hi Boris,
> >
> > > -----Original Message-----
> > > From: Boris Brezillon [mailto:boris.brezillon@xxxxxxxxxxx]
> > > Sent: Wednesday, October 17, 2018 1:00 PM
> > > To: Yogesh Narayan Gaur <yogeshnarayan.gaur@xxxxxxx>
> > > Cc: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxx>; Tudor Ambarus
> > > <tudor.ambarus@xxxxxxxxxxxxx>; marek.vasut@xxxxxxxxx;
> > > dwmw2@xxxxxxxxxxxxx; computersforpeace@xxxxxxxxx; richard@xxxxxx;
> > > linux-kernel@xxxxxxxxxxxxxxx; nicolas.ferre@xxxxxxxxxxxxx;
> > > cyrille.pitchen@xxxxxxxxxxxxx; linux-mtd@xxxxxxxxxxxxxxxxxxx;
> > > linux-arm- kernel@xxxxxxxxxxxxxxxxxxx; Cristian.Birsan@xxxxxxxxxxxxx
> > > Subject: Re: [PATCH v3 1/2] mtd: spi-nor: add support to non-uniform
> > > SFDP SPI NOR flash memories
> > >
> > > On Wed, 17 Oct 2018 09:10:45 +0200
> > > Boris Brezillon <boris.brezillon@xxxxxxxxxxx> wrote:
> > >
> > > > On Wed, 17 Oct 2018 09:07:24 +0200 Boris Brezillon
> > > > <boris.brezillon@xxxxxxxxxxx> wrote:
> > > >
> > > > > On Wed, 17 Oct 2018 02:07:43 +0000 Yogesh Narayan Gaur
> > > > > <yogeshnarayan.gaur@xxxxxxx> wrote:
> > > > >
> > > > > > >
> > > > > > Actually there is no entry of s25fs512s in current spi-nor.c file.
> > > > > > For my connected flash part, jedec ID read points to
> > > > > > s25fl512s. I have asked my board team to confirm the name of
> > > > > > exact connected flash part. When I check the data sheet of
> > > > > > s25fs512s, it also points to the same Jedec ID information. {
> > > > > > "s25fl512s", INFO(0x010220, 0x4d00, 256
> > > > > > * 1024, 256, ....}
> > > > > >
> > > > > > But as stated earlier, if I skip reading SFDP or read using
> > > > > > 1-1-1 protocol then read are always correct. For 1-4-4
> > > > > > protocol read are wrong and on further debugging found that
> > > > > > Read code of 0x6C is being send as opcode instead of 0xEC.
> > > > > >
> > > > > > If I revert this patch, reads are working fine.
> > > > >
> > > > > Can you try with the following patch?
> > > > >
> > > >
> > > > Hm, nevermind. The problem is actually not related to 4B vs non-4B
> > > > mode but 1-1-4 vs 1-4-4 modes.
> > Yes, that's only I have stated in my first mail that instead of 1-4-4 mode read
> opcode is being sent for 1-1-4 mode.
> > > >
> > >
> > > Can you try with this patch applied?
> > >
> > With suggested patch, read for protocol 1-4-4 working correctly.
> >
> > [ 1.625360] m25p80 spi0.0: found s25fl512s, expected m25p80
> > [ 1.631094] m25p80 spi0.0: failed to parse SMPT (err = -22)
> > [ 1.636661] 261 8c4c780 opcode(read:eb, pp:2, erase:d8)
> > [ 1.641878] 266 8c4c780 opcode(read:ec, pp:12, erase:dc)
> > [ 1.647200] m25p80 spi0.0: s25fl512s (65536 Kbytes)
> >
>
> Okay, let's try this one to see why the SMPT parsing fails.
>

Please find the below info for the SMPT table read from the flash
[ 1.631085] spi_nor_get_map_in_use:2880 smpt[0]=08ff65fc
[ 1.636393] spi_nor_get_map_in_use:2880 smpt[1]=00000004
[ 1.641696] spi_nor_get_map_in_use:2880 smpt[2]=04ff65fc
[ 1.646998] spi_nor_get_map_in_use:2880 smpt[3]=00000002
[ 1.652302] spi_nor_get_map_in_use:2880 smpt[4]=02ff65fd
[ 1.657606] spi_nor_get_map_in_use:2880 smpt[5]=00000004
[ 1.662911] spi_nor_get_map_in_use:2880 smpt[6]=ff0201fe
[ 1.668215] spi_nor_get_map_in_use:2880 smpt[7]=00007ff1
[ 1.673520] spi_nor_get_map_in_use:2880 smpt[8]=00037ff4
[ 1.678825] spi_nor_get_map_in_use:2880 smpt[9]=03fbfff4
[ 1.684128] spi_nor_get_map_in_use:2880 smpt[10]=ff0203fe
[ 1.689519] spi_nor_get_map_in_use:2880 smpt[11]=03fbfff4
[ 1.694911] spi_nor_get_map_in_use:2880 smpt[12]=00037ff4
[ 1.700303] spi_nor_get_map_in_use:2880 smpt[13]=00007ff1
[ 1.705693] spi_nor_get_map_in_use:2880 smpt[14]=ff0005ff
[ 1.711081] spi_nor_get_map_in_use:2880 smpt[15]=03fffff4
[ 1.716470] spi_nor_get_map_in_use:2910 NO map_id
[ 1.721165] spi_nor_parse_smpt:3055
[ 1.724645] m25p80 spi0.0: failed to parse SMPT (err = -22)

I have checked that all these information are matching with the fields specified in this flash data sheet [1], page 131-133.

Below is the full debug patch.

--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -2863,22 +2863,28 @@ static u8 spi_nor_smpt_read_dummy(const struct spi_nor *nor, const u32 settings)
* @nor: pointer to a 'struct spi_nor'
* @smpt: pointer to the sector map parameter table
*/
-static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt)
+static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt, u32 smpt_len)
{
const u32 *ret = NULL;
- u32 i, addr;
+ u32 i, addr, nmaps;
int err;
u8 addr_width, read_opcode, read_dummy;
u8 read_data_mask, data_byte, map_id;
+ bool map_id_is_valid = false;

addr_width = nor->addr_width;
read_dummy = nor->read_dummy;
read_opcode = nor->read_opcode;

+ for (i = 0; i<smpt_len; i++)
+ pr_info("%s:%i smpt[%d]=%08x\n", __func__, __LINE__, i, smpt[i]);
+
map_id = 0;
- i = 0;
/* Determine if there are any optional Detection Command Descriptors */
- while (!(smpt[i] & SMPT_DESC_TYPE_MAP)) {
+ for (i = 0; i< smpt_len; i++) {
+ if (!(smpt[i] & SMPT_DESC_TYPE_MAP))
+ break;
+
read_data_mask = SMPT_CMD_READ_DATA(smpt[i]);
nor->addr_width = spi_nor_smpt_addr_width(nor, smpt[i]);
nor->read_dummy = spi_nor_smpt_read_dummy(nor, smpt[i]);
@@ -2894,18 +2900,35 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt)
* Configuration that is currently in use.
*/
map_id = map_id << 1 | !!(data_byte & read_data_mask);
+ map_id_is_valid = true;
i = i + 2;
}

- /* Find the matching configuration map */
- while (SMPT_MAP_ID(smpt[i]) != map_id) {
- if (smpt[i] & SMPT_DESC_END)
- goto out;
+ if (map_id_is_valid)
+ pr_info("%s:%i map_id=%d\n", __func__, __LINE__, map_id);
+ else
+ pr_info("%s:%i NO map_id\n", __func__, __LINE__);
+
+ for (nmaps = 0; nmaps< smpt_len; nmaps++) {
+ if(!(smpt[nmaps] & SMPT_DESC_TYPE_MAP))
+ continue;
+
+ if(!map_id_is_valid) {
+ if (nmaps) {
+ ret = NULL;
+ break;
+ }
+
+ ret = smpt+nmaps;
+ } else if (map_id == SMPT_MAP_ID(smpt[nmaps])) {
+ ret = smpt+nmaps;
+ break;
+ }
+
/* increment the table index to the next map */
- i += SMPT_MAP_REGION_COUNT(smpt[i]) + 1;
+ nmaps += SMPT_MAP_REGION_COUNT(smpt[nmaps]) + 1;
}

- ret = smpt + i;
/* fall through */
out:
nor->addr_width = addr_width;
@@ -3027,8 +3050,9 @@ static int spi_nor_parse_smpt(struct spi_nor *nor,
for (i = 0; i < smpt_header->length; i++)
smpt[i] = le32_to_cpu(smpt[i]);

- sector_map = spi_nor_get_map_in_use(nor, smpt);
+ sector_map = spi_nor_get_map_in_use(nor, smpt, smpt_header->length);
if (!sector_map) {
+ pr_info("%s:%i\n", __func__, __LINE__);
ret = -EINVAL;
goto out;
}
@@ -3139,6 +3167,17 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor,
switch (SFDP_PARAM_HEADER_ID(param_header)) {
case SFDP_SECTOR_MAP_ID:
err = spi_nor_parse_smpt(nor, param_header);
+ if (err) {
+ dev_warn(dev,
+ "failed to parse SMPT (err = %d)\n",
+ err);
+ /*
+ * SMPT parsing is optional, let's not drop
+ * all information we extracted so far just
+ * because it failed.
+ */
+ err = 0;
+ }
break;

default:
[1] http://www.cypress.com/documentation/datasheets/s25fs512s-512-mbit-18-v-serial-peripheral-interface-multi-io-non-volatile

--
Regards
Yogesh Gaur
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