2023-09-22 12:26:55

by Rouven Czerwinski

[permalink] [raw]
Subject: [PATCH] mtd: rawnand: check nand support for cache reads

Both the JEDEC and ONFI specification say that read cache sequential
support is an optional command. This means that we not only need to
check whether the individual controller implements the command, we also
need to check the parameter pages for both ONFI and JEDEC NAND flashes
before enabling sequential cache reads.

This fixes support for NAND flashes which don't support enabling cache
reads, i.e. Samsung K9F4G08U0F or Toshiba TC58NVG0S3HTA00.

Sequential cache reads are no only available for ONFI and JEDEC devices,
if individual vendors implement this, it needs to be enabled per vendor.

Tested on i.MX6Q with a Samsung NAND flash chip that doesn't support
sequential reads.

Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache reads")

Signed-off-by: Rouven Czerwinski <[email protected]>
---
@Martin, Måns:
I would appreciate if you could test this on your hardware.

@Miguel:
I didn't have the time to test this on ONFI/JEDEC devices with support
yet, I'd be fine if you hold off merging this.

drivers/mtd/nand/raw/nand_base.c | 3 +++
drivers/mtd/nand/raw/nand_jedec.c | 3 +++
drivers/mtd/nand/raw/nand_onfi.c | 3 +++
include/linux/mtd/jedec.h | 3 +++
include/linux/mtd/onfi.h | 1 +
include/linux/mtd/rawnand.h | 1 +
6 files changed, 14 insertions(+)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index d4b55155aeae..1fcac403cee6 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -5110,6 +5110,9 @@ static void rawnand_check_cont_read_support(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);

+ if (!chip->parameters.supports_read_cache)
+ return;
+
if (chip->read_retries)
return;

diff --git a/drivers/mtd/nand/raw/nand_jedec.c b/drivers/mtd/nand/raw/nand_jedec.c
index 836757717660..e6ecbc4b2493 100644
--- a/drivers/mtd/nand/raw/nand_jedec.c
+++ b/drivers/mtd/nand/raw/nand_jedec.c
@@ -94,6 +94,9 @@ int nand_jedec_detect(struct nand_chip *chip)
goto free_jedec_param_page;
}

+ if (p->opt_cmd[0] & JEDEC_OPT_CMD_READ_CACHE)
+ chip->parameters.supports_read_cache;
+
memorg->pagesize = le32_to_cpu(p->byte_per_page);
mtd->writesize = memorg->pagesize;

diff --git a/drivers/mtd/nand/raw/nand_onfi.c b/drivers/mtd/nand/raw/nand_onfi.c
index f15ef90aec8c..bf79bf2b5866 100644
--- a/drivers/mtd/nand/raw/nand_onfi.c
+++ b/drivers/mtd/nand/raw/nand_onfi.c
@@ -303,6 +303,9 @@ int nand_onfi_detect(struct nand_chip *chip)
ONFI_FEATURE_ADDR_TIMING_MODE, 1);
}

+ if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_READ_CACHE)
+ chip->parameters.supports_read_cache;
+
onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
if (!onfi) {
ret = -ENOMEM;
diff --git a/include/linux/mtd/jedec.h b/include/linux/mtd/jedec.h
index 0b6b59f7cfbd..56047a4e54c9 100644
--- a/include/linux/mtd/jedec.h
+++ b/include/linux/mtd/jedec.h
@@ -21,6 +21,9 @@ struct jedec_ecc_info {
/* JEDEC features */
#define JEDEC_FEATURE_16_BIT_BUS (1 << 0)

+/* JEDEC Optional Commands */
+#define JEDEC_OPT_CMD_READ_CACHE BIT(1)
+
struct nand_jedec_params {
/* rev info and features block */
/* 'J' 'E' 'S' 'D' */
diff --git a/include/linux/mtd/onfi.h b/include/linux/mtd/onfi.h
index a7376f9beddf..55ab2e4d62f9 100644
--- a/include/linux/mtd/onfi.h
+++ b/include/linux/mtd/onfi.h
@@ -55,6 +55,7 @@
#define ONFI_SUBFEATURE_PARAM_LEN 4

/* ONFI optional commands SET/GET FEATURES supported? */
+#define ONFI_OPT_CMD_READ_CACHE BIT(1)
#define ONFI_OPT_CMD_SET_GET_FEATURES BIT(2)

struct nand_onfi_params {
diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
index 90a141ba2a5a..766856fcaba8 100644
--- a/include/linux/mtd/rawnand.h
+++ b/include/linux/mtd/rawnand.h
@@ -233,6 +233,7 @@ struct nand_parameters {
/* Generic parameters */
const char *model;
bool supports_set_get_features;
+ bool supports_read_cache;
DECLARE_BITMAP(set_feature_list, ONFI_FEATURE_NUMBER);
DECLARE_BITMAP(get_feature_list, ONFI_FEATURE_NUMBER);

--
2.42.0


2023-09-22 13:50:33

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] mtd: rawnand: check nand support for cache reads

Hi Rouven,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.6-rc2 next-20230921]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Rouven-Czerwinski/mtd-rawnand-check-nand-support-for-cache-reads/20230922-180317
base: linus/master
patch link: https://lore.kernel.org/r/20230922100116.145090-1-r.czerwinski%40pengutronix.de
patch subject: [PATCH] mtd: rawnand: check nand support for cache reads
config: m68k-allyesconfig (https://download.01.org/0day-ci/archive/20230922/[email protected]/config)
compiler: m68k-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230922/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

drivers/mtd/nand/raw/nand_onfi.c: In function 'nand_onfi_detect':
>> drivers/mtd/nand/raw/nand_onfi.c:307:33: warning: statement with no effect [-Wunused-value]
307 | chip->parameters.supports_read_cache;
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
--
drivers/mtd/nand/raw/nand_jedec.c: In function 'nand_jedec_detect':
>> drivers/mtd/nand/raw/nand_jedec.c:98:33: warning: statement with no effect [-Wunused-value]
98 | chip->parameters.supports_read_cache;
| ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~


vim +307 drivers/mtd/nand/raw/nand_onfi.c

140
141 /*
142 * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
143 */
144 int nand_onfi_detect(struct nand_chip *chip)
145 {
146 struct nand_device *base = &chip->base;
147 struct mtd_info *mtd = nand_to_mtd(chip);
148 struct nand_memory_organization *memorg;
149 struct nand_onfi_params *p = NULL, *pbuf;
150 struct onfi_params *onfi;
151 bool use_datain = false;
152 int onfi_version = 0;
153 char id[4];
154 int i, ret, val;
155 u16 crc;
156
157 memorg = nanddev_get_memorg(&chip->base);
158
159 /* Try ONFI for unknown chip or LP */
160 ret = nand_readid_op(chip, 0x20, id, sizeof(id));
161 if (ret || strncmp(id, "ONFI", 4))
162 return 0;
163
164 /* ONFI chip: allocate a buffer to hold its parameter page */
165 pbuf = kzalloc((sizeof(*pbuf) * ONFI_PARAM_PAGES), GFP_KERNEL);
166 if (!pbuf)
167 return -ENOMEM;
168
169 if (!nand_has_exec_op(chip) || chip->controller->supported_op.data_only_read)
170 use_datain = true;
171
172 for (i = 0; i < ONFI_PARAM_PAGES; i++) {
173 if (!i)
174 ret = nand_read_param_page_op(chip, 0, &pbuf[i],
175 sizeof(*pbuf));
176 else if (use_datain)
177 ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf),
178 true, false);
179 else
180 ret = nand_change_read_column_op(chip, sizeof(*pbuf) * i,
181 &pbuf[i], sizeof(*pbuf),
182 true);
183 if (ret) {
184 ret = 0;
185 goto free_onfi_param_page;
186 }
187
188 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
189 if (crc == le16_to_cpu(pbuf[i].crc)) {
190 p = &pbuf[i];
191 break;
192 }
193 }
194
195 if (i == ONFI_PARAM_PAGES) {
196 const void *srcbufs[ONFI_PARAM_PAGES];
197 unsigned int j;
198
199 for (j = 0; j < ONFI_PARAM_PAGES; j++)
200 srcbufs[j] = pbuf + j;
201
202 pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
203 nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, pbuf,
204 sizeof(*pbuf));
205
206 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)pbuf, 254);
207 if (crc != le16_to_cpu(pbuf->crc)) {
208 pr_err("ONFI parameter recovery failed, aborting\n");
209 goto free_onfi_param_page;
210 }
211 p = pbuf;
212 }
213
214 if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
215 chip->manufacturer.desc->ops->fixup_onfi_param_page)
216 chip->manufacturer.desc->ops->fixup_onfi_param_page(chip, p);
217
218 /* Check version */
219 val = le16_to_cpu(p->revision);
220 if (val & ONFI_VERSION_2_3)
221 onfi_version = 23;
222 else if (val & ONFI_VERSION_2_2)
223 onfi_version = 22;
224 else if (val & ONFI_VERSION_2_1)
225 onfi_version = 21;
226 else if (val & ONFI_VERSION_2_0)
227 onfi_version = 20;
228 else if (val & ONFI_VERSION_1_0)
229 onfi_version = 10;
230
231 if (!onfi_version) {
232 pr_info("unsupported ONFI version: %d\n", val);
233 goto free_onfi_param_page;
234 }
235
236 sanitize_string(p->manufacturer, sizeof(p->manufacturer));
237 sanitize_string(p->model, sizeof(p->model));
238 chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
239 if (!chip->parameters.model) {
240 ret = -ENOMEM;
241 goto free_onfi_param_page;
242 }
243
244 memorg->pagesize = le32_to_cpu(p->byte_per_page);
245 mtd->writesize = memorg->pagesize;
246
247 /*
248 * pages_per_block and blocks_per_lun may not be a power-of-2 size
249 * (don't ask me who thought of this...). MTD assumes that these
250 * dimensions will be power-of-2, so just truncate the remaining area.
251 */
252 memorg->pages_per_eraseblock =
253 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
254 mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
255
256 memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
257 mtd->oobsize = memorg->oobsize;
258
259 memorg->luns_per_target = p->lun_count;
260 memorg->planes_per_lun = 1 << p->interleaved_bits;
261
262 /* See erasesize comment */
263 memorg->eraseblocks_per_lun =
264 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
265 memorg->max_bad_eraseblocks_per_lun = le32_to_cpu(p->blocks_per_lun);
266 memorg->bits_per_cell = p->bits_per_cell;
267
268 if (le16_to_cpu(p->features) & ONFI_FEATURE_16_BIT_BUS)
269 chip->options |= NAND_BUSWIDTH_16;
270
271 if (p->ecc_bits != 0xff) {
272 struct nand_ecc_props requirements = {
273 .strength = p->ecc_bits,
274 .step_size = 512,
275 };
276
277 nanddev_set_ecc_requirements(base, &requirements);
278 } else if (onfi_version >= 21 &&
279 (le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
280
281 /*
282 * The nand_flash_detect_ext_param_page() uses the
283 * Change Read Column command which maybe not supported
284 * by the chip->legacy.cmdfunc. So try to update the
285 * chip->legacy.cmdfunc now. We do not replace user supplied
286 * command function.
287 */
288 nand_legacy_adjust_cmdfunc(chip);
289
290 /* The Extended Parameter Page is supported since ONFI 2.1. */
291 if (nand_flash_detect_ext_param_page(chip, p))
292 pr_warn("Failed to detect ONFI extended param page\n");
293 } else {
294 pr_warn("Could not retrieve ONFI ECC requirements\n");
295 }
296
297 /* Save some parameters from the parameter page for future use */
298 if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES) {
299 chip->parameters.supports_set_get_features = true;
300 bitmap_set(chip->parameters.get_feature_list,
301 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
302 bitmap_set(chip->parameters.set_feature_list,
303 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
304 }
305
306 if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_READ_CACHE)
> 307 chip->parameters.supports_read_cache;

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

2023-09-22 14:04:45

by Miquel Raynal

[permalink] [raw]
Subject: Re: [PATCH] mtd: rawnand: check nand support for cache reads

Hi Rouven,

Thanks a lot for the investigation and the patch!

[email protected] wrote on Fri, 22 Sep 2023 12:01:13 +0200:

Would you mind changing the title to
"mtd: rawnand: Ensure the nand chip supports cached reads"

> Both the JEDEC and ONFI specification say that read cache sequential
> support is an optional command.

I clearly overlooked that part, just checking the set/get_features()
entries as usual, good catch.

> This means that we not only need to
> check whether the individual controller implements the command, we also

The controller itself does not implement the command, but may or may
not support it (can you please update the sentence?).

> need to check the parameter pages for both ONFI and JEDEC NAND flashes
> before enabling sequential cache reads.
>
> This fixes support for NAND flashes which don't support enabling cache
> reads, i.e. Samsung K9F4G08U0F or Toshiba TC58NVG0S3HTA00.
>
> Sequential cache reads are no only available for ONFI and JEDEC devices,
> if individual vendors implement this, it needs to be enabled per vendor.

Agreed.

> Tested on i.MX6Q with a Samsung NAND flash chip that doesn't support
> sequential reads.
>
> Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache reads")
>

Please remove this empty line and instead add:

Cc: [email protected]

> Signed-off-by: Rouven Czerwinski <[email protected]>
> ---
> @Martin, Måns:
> I would appreciate if you could test this on your hardware.

That would me much appreciated!

I also added Alexander who also had troubles with this patchset, could
you check on your setup if that solves the issue?

> @Miguel:
> I didn't have the time to test this on ONFI/JEDEC devices with support
> yet, I'd be fine if you hold off merging this.

Of course. I was about to send a revert but that looks a promising fix,
let's see how it goes.

>
> drivers/mtd/nand/raw/nand_base.c | 3 +++
> drivers/mtd/nand/raw/nand_jedec.c | 3 +++
> drivers/mtd/nand/raw/nand_onfi.c | 3 +++
> include/linux/mtd/jedec.h | 3 +++
> include/linux/mtd/onfi.h | 1 +
> include/linux/mtd/rawnand.h | 1 +
> 6 files changed, 14 insertions(+)
>

Thanks,
Miquèl

2023-09-22 16:27:43

by Martin Hundebøll

[permalink] [raw]
Subject: Re: [PATCH] mtd: rawnand: check nand support for cache reads

On Fri, 2023-09-22 at 12:01 +0200, Rouven Czerwinski wrote:
> Both the JEDEC and ONFI specification say that read cache sequential
> support is an optional command. This means that we not only need to
> check whether the individual controller implements the command, we
> also
> need to check the parameter pages for both ONFI and JEDEC NAND
> flashes
> before enabling sequential cache reads.
>
> This fixes support for NAND flashes which don't support enabling
> cache
> reads, i.e. Samsung K9F4G08U0F or Toshiba TC58NVG0S3HTA00.
>
> Sequential cache reads are no only available for ONFI and JEDEC
> devices,
> if individual vendors implement this, it needs to be enabled per
> vendor.
>
> Tested on i.MX6Q with a Samsung NAND flash chip that doesn't support
> sequential reads.
>
> Fixes: 003fe4b9545b ("mtd: rawnand: Support for sequential cache
> reads")
>
> Signed-off-by: Rouven Czerwinski <[email protected]>
> ---
> @Martin, Måns:
> I would appreciate if you could test this on your hardware.
>
> @Miguel:
> I didn't have the time to test this on ONFI/JEDEC devices with
> support
> yet, I'd be fine if you hold off merging this.
>
>  drivers/mtd/nand/raw/nand_base.c  | 3 +++
>  drivers/mtd/nand/raw/nand_jedec.c | 3 +++
>  drivers/mtd/nand/raw/nand_onfi.c  | 3 +++
>  include/linux/mtd/jedec.h         | 3 +++
>  include/linux/mtd/onfi.h          | 1 +
>  include/linux/mtd/rawnand.h       | 1 +
>  6 files changed, 14 insertions(+)
>
> diff --git a/drivers/mtd/nand/raw/nand_base.c
> b/drivers/mtd/nand/raw/nand_base.c
> index d4b55155aeae..1fcac403cee6 100644
> --- a/drivers/mtd/nand/raw/nand_base.c
> +++ b/drivers/mtd/nand/raw/nand_base.c
> @@ -5110,6 +5110,9 @@ static void
> rawnand_check_cont_read_support(struct nand_chip *chip)
>  {
>         struct mtd_info *mtd = nand_to_mtd(chip);
>  
> +       if (!chip->parameters.supports_read_cache)
> +               return;
> +
>         if (chip->read_retries)
>                 return;
>  
> diff --git a/drivers/mtd/nand/raw/nand_jedec.c
> b/drivers/mtd/nand/raw/nand_jedec.c
> index 836757717660..e6ecbc4b2493 100644
> --- a/drivers/mtd/nand/raw/nand_jedec.c
> +++ b/drivers/mtd/nand/raw/nand_jedec.c
> @@ -94,6 +94,9 @@ int nand_jedec_detect(struct nand_chip *chip)
>                 goto free_jedec_param_page;
>         }
>  
> +       if (p->opt_cmd[0] & JEDEC_OPT_CMD_READ_CACHE)
> +               chip->parameters.supports_read_cache;

Missing ` = true` here ?

> +
>         memorg->pagesize = le32_to_cpu(p->byte_per_page);
>         mtd->writesize = memorg->pagesize;
>  
> diff --git a/drivers/mtd/nand/raw/nand_onfi.c
> b/drivers/mtd/nand/raw/nand_onfi.c
> index f15ef90aec8c..bf79bf2b5866 100644
> --- a/drivers/mtd/nand/raw/nand_onfi.c
> +++ b/drivers/mtd/nand/raw/nand_onfi.c
> @@ -303,6 +303,9 @@ int nand_onfi_detect(struct nand_chip *chip)
>                            ONFI_FEATURE_ADDR_TIMING_MODE, 1);
>         }
>  
> +       if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_READ_CACHE)
> +               chip->parameters.supports_read_cache;

And here?

// Martin
> +
>         onfi = kzalloc(sizeof(*onfi), GFP_KERNEL);
>         if (!onfi) {
>                 ret = -ENOMEM;
> diff --git a/include/linux/mtd/jedec.h b/include/linux/mtd/jedec.h
> index 0b6b59f7cfbd..56047a4e54c9 100644
> --- a/include/linux/mtd/jedec.h
> +++ b/include/linux/mtd/jedec.h
> @@ -21,6 +21,9 @@ struct jedec_ecc_info {
>  /* JEDEC features */
>  #define JEDEC_FEATURE_16_BIT_BUS       (1 << 0)
>  
> +/* JEDEC Optional Commands */
> +#define JEDEC_OPT_CMD_READ_CACHE       BIT(1)
> +
>  struct nand_jedec_params {
>         /* rev info and features block */
>         /* 'J' 'E' 'S' 'D'  */
> diff --git a/include/linux/mtd/onfi.h b/include/linux/mtd/onfi.h
> index a7376f9beddf..55ab2e4d62f9 100644
> --- a/include/linux/mtd/onfi.h
> +++ b/include/linux/mtd/onfi.h
> @@ -55,6 +55,7 @@
>  #define ONFI_SUBFEATURE_PARAM_LEN      4
>  
>  /* ONFI optional commands SET/GET FEATURES supported? */
> +#define ONFI_OPT_CMD_READ_CACHE                BIT(1)
>  #define ONFI_OPT_CMD_SET_GET_FEATURES  BIT(2)
>  
>  struct nand_onfi_params {
> diff --git a/include/linux/mtd/rawnand.h
> b/include/linux/mtd/rawnand.h
> index 90a141ba2a5a..766856fcaba8 100644
> --- a/include/linux/mtd/rawnand.h
> +++ b/include/linux/mtd/rawnand.h
> @@ -233,6 +233,7 @@ struct nand_parameters {
>         /* Generic parameters */
>         const char *model;
>         bool supports_set_get_features;
> +       bool supports_read_cache;
>         DECLARE_BITMAP(set_feature_list, ONFI_FEATURE_NUMBER);
>         DECLARE_BITMAP(get_feature_list, ONFI_FEATURE_NUMBER);
>  

2023-09-29 23:13:29

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH] mtd: rawnand: check nand support for cache reads

Hi Rouven,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linus/master]
[also build test WARNING on v6.6-rc3 next-20230929]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Rouven-Czerwinski/mtd-rawnand-check-nand-support-for-cache-reads/20230922-180317
base: linus/master
patch link: https://lore.kernel.org/r/20230922100116.145090-1-r.czerwinski%40pengutronix.de
patch subject: [PATCH] mtd: rawnand: check nand support for cache reads
config: mips-qi_lb60_defconfig (https://download.01.org/0day-ci/archive/20230930/[email protected]/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230930/[email protected]/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

All warnings (new ones prefixed by >>):

>> drivers/mtd/nand/raw/nand_onfi.c:307:20: warning: expression result unused [-Wunused-value]
307 | chip->parameters.supports_read_cache;
| ~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~~~~
1 warning generated.
--
>> drivers/mtd/nand/raw/nand_jedec.c:98:20: warning: expression result unused [-Wunused-value]
98 | chip->parameters.supports_read_cache;
| ~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~~~~
1 warning generated.


vim +307 drivers/mtd/nand/raw/nand_onfi.c

140
141 /*
142 * Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
143 */
144 int nand_onfi_detect(struct nand_chip *chip)
145 {
146 struct nand_device *base = &chip->base;
147 struct mtd_info *mtd = nand_to_mtd(chip);
148 struct nand_memory_organization *memorg;
149 struct nand_onfi_params *p = NULL, *pbuf;
150 struct onfi_params *onfi;
151 bool use_datain = false;
152 int onfi_version = 0;
153 char id[4];
154 int i, ret, val;
155 u16 crc;
156
157 memorg = nanddev_get_memorg(&chip->base);
158
159 /* Try ONFI for unknown chip or LP */
160 ret = nand_readid_op(chip, 0x20, id, sizeof(id));
161 if (ret || strncmp(id, "ONFI", 4))
162 return 0;
163
164 /* ONFI chip: allocate a buffer to hold its parameter page */
165 pbuf = kzalloc((sizeof(*pbuf) * ONFI_PARAM_PAGES), GFP_KERNEL);
166 if (!pbuf)
167 return -ENOMEM;
168
169 if (!nand_has_exec_op(chip) || chip->controller->supported_op.data_only_read)
170 use_datain = true;
171
172 for (i = 0; i < ONFI_PARAM_PAGES; i++) {
173 if (!i)
174 ret = nand_read_param_page_op(chip, 0, &pbuf[i],
175 sizeof(*pbuf));
176 else if (use_datain)
177 ret = nand_read_data_op(chip, &pbuf[i], sizeof(*pbuf),
178 true, false);
179 else
180 ret = nand_change_read_column_op(chip, sizeof(*pbuf) * i,
181 &pbuf[i], sizeof(*pbuf),
182 true);
183 if (ret) {
184 ret = 0;
185 goto free_onfi_param_page;
186 }
187
188 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)&pbuf[i], 254);
189 if (crc == le16_to_cpu(pbuf[i].crc)) {
190 p = &pbuf[i];
191 break;
192 }
193 }
194
195 if (i == ONFI_PARAM_PAGES) {
196 const void *srcbufs[ONFI_PARAM_PAGES];
197 unsigned int j;
198
199 for (j = 0; j < ONFI_PARAM_PAGES; j++)
200 srcbufs[j] = pbuf + j;
201
202 pr_warn("Could not find a valid ONFI parameter page, trying bit-wise majority to recover it\n");
203 nand_bit_wise_majority(srcbufs, ONFI_PARAM_PAGES, pbuf,
204 sizeof(*pbuf));
205
206 crc = onfi_crc16(ONFI_CRC_BASE, (u8 *)pbuf, 254);
207 if (crc != le16_to_cpu(pbuf->crc)) {
208 pr_err("ONFI parameter recovery failed, aborting\n");
209 goto free_onfi_param_page;
210 }
211 p = pbuf;
212 }
213
214 if (chip->manufacturer.desc && chip->manufacturer.desc->ops &&
215 chip->manufacturer.desc->ops->fixup_onfi_param_page)
216 chip->manufacturer.desc->ops->fixup_onfi_param_page(chip, p);
217
218 /* Check version */
219 val = le16_to_cpu(p->revision);
220 if (val & ONFI_VERSION_2_3)
221 onfi_version = 23;
222 else if (val & ONFI_VERSION_2_2)
223 onfi_version = 22;
224 else if (val & ONFI_VERSION_2_1)
225 onfi_version = 21;
226 else if (val & ONFI_VERSION_2_0)
227 onfi_version = 20;
228 else if (val & ONFI_VERSION_1_0)
229 onfi_version = 10;
230
231 if (!onfi_version) {
232 pr_info("unsupported ONFI version: %d\n", val);
233 goto free_onfi_param_page;
234 }
235
236 sanitize_string(p->manufacturer, sizeof(p->manufacturer));
237 sanitize_string(p->model, sizeof(p->model));
238 chip->parameters.model = kstrdup(p->model, GFP_KERNEL);
239 if (!chip->parameters.model) {
240 ret = -ENOMEM;
241 goto free_onfi_param_page;
242 }
243
244 memorg->pagesize = le32_to_cpu(p->byte_per_page);
245 mtd->writesize = memorg->pagesize;
246
247 /*
248 * pages_per_block and blocks_per_lun may not be a power-of-2 size
249 * (don't ask me who thought of this...). MTD assumes that these
250 * dimensions will be power-of-2, so just truncate the remaining area.
251 */
252 memorg->pages_per_eraseblock =
253 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
254 mtd->erasesize = memorg->pages_per_eraseblock * memorg->pagesize;
255
256 memorg->oobsize = le16_to_cpu(p->spare_bytes_per_page);
257 mtd->oobsize = memorg->oobsize;
258
259 memorg->luns_per_target = p->lun_count;
260 memorg->planes_per_lun = 1 << p->interleaved_bits;
261
262 /* See erasesize comment */
263 memorg->eraseblocks_per_lun =
264 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
265 memorg->max_bad_eraseblocks_per_lun = le32_to_cpu(p->blocks_per_lun);
266 memorg->bits_per_cell = p->bits_per_cell;
267
268 if (le16_to_cpu(p->features) & ONFI_FEATURE_16_BIT_BUS)
269 chip->options |= NAND_BUSWIDTH_16;
270
271 if (p->ecc_bits != 0xff) {
272 struct nand_ecc_props requirements = {
273 .strength = p->ecc_bits,
274 .step_size = 512,
275 };
276
277 nanddev_set_ecc_requirements(base, &requirements);
278 } else if (onfi_version >= 21 &&
279 (le16_to_cpu(p->features) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
280
281 /*
282 * The nand_flash_detect_ext_param_page() uses the
283 * Change Read Column command which maybe not supported
284 * by the chip->legacy.cmdfunc. So try to update the
285 * chip->legacy.cmdfunc now. We do not replace user supplied
286 * command function.
287 */
288 nand_legacy_adjust_cmdfunc(chip);
289
290 /* The Extended Parameter Page is supported since ONFI 2.1. */
291 if (nand_flash_detect_ext_param_page(chip, p))
292 pr_warn("Failed to detect ONFI extended param page\n");
293 } else {
294 pr_warn("Could not retrieve ONFI ECC requirements\n");
295 }
296
297 /* Save some parameters from the parameter page for future use */
298 if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES) {
299 chip->parameters.supports_set_get_features = true;
300 bitmap_set(chip->parameters.get_feature_list,
301 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
302 bitmap_set(chip->parameters.set_feature_list,
303 ONFI_FEATURE_ADDR_TIMING_MODE, 1);
304 }
305
306 if (le16_to_cpu(p->opt_cmd) & ONFI_OPT_CMD_READ_CACHE)
> 307 chip->parameters.supports_read_cache;

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki