| Message ID | 1486572781-28808-2-git-send-email-kdasu.kdev@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 02/08/2017 05:53 PM, Kamal Dasu wrote: > Refactored spi_nor_scan() code to add spi_nor_reset() function that > programs the nand device to: nand device ? > 1) remove flash protection if applicable > 2) set read mode to quad mode if configured such > 3) set the address width based on the flash size and vendor > > On pm resume spi-nor flash may need to be reconfigured after power > reset, there is no need to go through a full spi_nor_scan(), flash > device driver needs to call spi_nor_reset() to reprogram the flash > to its probed state. > > Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> > --- > drivers/mtd/spi-nor/spi-nor.c | 62 ++++++++++++++++++++++++++++--------------- > include/linux/mtd/spi-nor.h | 21 ++++++++++++++- > 2 files changed, 61 insertions(+), 22 deletions(-) > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index da7cd69..8e3d8bd 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -1312,6 +1312,41 @@ static int spi_nor_check(struct spi_nor *nor) > return 0; > } > > +int spi_nor_reset(struct spi_nor *nor) > +{ > + int ret = 0; > + const struct flash_info *info = nor->info; > + struct device *dev = nor->dev; Does this reset the SPI NOR (as in, really send a reset opcode) ? It doesn't, so the naming is confusing. This should probably be something like "spi_nor_init()" or "spi_nor_setup()" , no ? > + /* > + * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up > + * with the software protection bits set > + */ > + > + if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || > + JEDEC_MFR(info) == SNOR_MFR_INTEL || > + JEDEC_MFR(info) == SNOR_MFR_SST || > + info->flags & SPI_NOR_HAS_LOCK) { > + write_enable(nor); > + write_sr(nor, 0); > + spi_nor_wait_till_ready(nor); > + } > + > + if (nor->flash_read == SPI_NOR_QUAD) { > + ret = set_quad_mode(nor, info); > + if (ret) { > + dev_err(dev, "quad mode not supported\n"); > + return ret; > + } > + } > + > + if (nor->addr_width == 4 && JEDEC_MFR(info) != SNOR_MFR_SPANSION) > + set_4byte(nor, info, 1); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(spi_nor_reset); > + > int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > { > const struct flash_info *info = NULL; > @@ -1357,22 +1392,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > } > } > > + nor->info = info; > mutex_init(&nor->lock); > > - /* > - * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up > - * with the software protection bits set > - */ > - > - if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || > - JEDEC_MFR(info) == SNOR_MFR_INTEL || > - JEDEC_MFR(info) == SNOR_MFR_SST || > - info->flags & SPI_NOR_HAS_LOCK) { > - write_enable(nor); > - write_sr(nor, 0); > - spi_nor_wait_till_ready(nor); > - } > - > if (!mtd->name) > mtd->name = dev_name(dev); > mtd->priv = nor; > @@ -1447,11 +1469,6 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > > /* Quad/Dual-read mode takes precedence over fast/normal */ > if (mode == SPI_NOR_QUAD && info->flags & SPI_NOR_QUAD_READ) { > - ret = set_quad_mode(nor, info); > - if (ret) { > - dev_err(dev, "quad mode not supported\n"); > - return ret; > - } > nor->flash_read = SPI_NOR_QUAD; > } else if (mode == SPI_NOR_DUAL && info->flags & SPI_NOR_DUAL_READ) { > nor->flash_read = SPI_NOR_DUAL; > @@ -1503,8 +1520,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > /* No small sector erase for 4-byte command set */ > nor->erase_opcode = SPINOR_OP_SE_4B; > mtd->erasesize = info->sector_size; > - } else > - set_4byte(nor, info, 1); > + } > } else { > nor->addr_width = 3; > } > @@ -1517,6 +1533,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > > nor->read_dummy = spi_nor_read_dummy_cycles(nor); > > + ret = spi_nor_reset(nor); > + if (ret) > + return ret; > + > dev_info(dev, "%s (%lld Kbytes)\n", info->name, > (long long)mtd->size >> 10); > > diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h > index c425c7b..4733c04 100644 > --- a/include/linux/mtd/spi-nor.h > +++ b/include/linux/mtd/spi-nor.h > @@ -121,6 +121,8 @@ enum spi_nor_option_flags { > SNOR_F_HAS_SR_TB = BIT(1), > }; > > +struct flash_info; > + > /** > * struct spi_nor - Structure for defining a the SPI NOR layer > * @mtd: point to a mtd_info structure > @@ -154,6 +156,7 @@ enum spi_nor_option_flags { > * @priv: the private data > */ > struct spi_nor { > + const struct flash_info *info; > struct mtd_info mtd; > struct mutex lock; > struct device *dev; > @@ -198,12 +201,28 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor) > } > > /** > + * spi_nor_reset() - reset scan the SPI NOR > + * @nor: the spi_nor structure > + * > + * The drivers uses this function to reset the SPI NOR flash device to > + * its initial scanned state, it shall use all nor information set on poweron > + * for the read mode, address width and enabling write mode for certain > + * manufacturers. This would be needed to be called for flash devices that are > + * reset during power management. > + * > + * The chip type name can be provided through the @name parameter. > + * > + * Return: 0 for success, others for failure. > + */ > +int spi_nor_reset(struct spi_nor *nor); > + > +/** > * spi_nor_scan() - scan the SPI NOR > * @nor: the spi_nor structure > * @name: the chip type name > * @mode: the read mode supported by the driver > * > - * The drivers can use this fuction to scan the SPI NOR. > + * The drivers can use this function to scan the SPI NOR. > * In the scanning, it will try to get all the necessary information to > * fill the mtd_info{} and the spi_nor{}. > * >
Hi Kamal, Le 08/02/2017 à 17:53, Kamal Dasu a écrit : > Refactored spi_nor_scan() code to add spi_nor_reset() function that > programs the nand device to: > 1) remove flash protection if applicable > 2) set read mode to quad mode if configured such > 3) set the address width based on the flash size and vendor > > On pm resume spi-nor flash may need to be reconfigured after power > reset, there is no need to go through a full spi_nor_scan(), flash > device driver needs to call spi_nor_reset() to reprogram the flash > to its probed state. > > Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> > --- > drivers/mtd/spi-nor/spi-nor.c | 62 ++++++++++++++++++++++++++++--------------- > include/linux/mtd/spi-nor.h | 21 ++++++++++++++- > 2 files changed, 61 insertions(+), 22 deletions(-) > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index da7cd69..8e3d8bd 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -1312,6 +1312,41 @@ static int spi_nor_check(struct spi_nor *nor) > return 0; > } > > +int spi_nor_reset(struct spi_nor *nor) > +{ > + int ret = 0; > + const struct flash_info *info = nor->info; > + struct device *dev = nor->dev; > + > + /* > + * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up > + * with the software protection bits set > + */ > + > + if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || > + JEDEC_MFR(info) == SNOR_MFR_INTEL || > + JEDEC_MFR(info) == SNOR_MFR_SST || > + info->flags & SPI_NOR_HAS_LOCK) { > + write_enable(nor); > + write_sr(nor, 0); > + spi_nor_wait_till_ready(nor); > + } > + > + if (nor->flash_read == SPI_NOR_QUAD) { > + ret = set_quad_mode(nor, info); > + if (ret) { > + dev_err(dev, "quad mode not supported\n"); > + return ret; > + } > + } > + > + if (nor->addr_width == 4 && JEDEC_MFR(info) != SNOR_MFR_SPANSION) > + set_4byte(nor, info, 1); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(spi_nor_reset); > + > int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > { > const struct flash_info *info = NULL; > @@ -1357,22 +1392,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > } > } > > + nor->info = info; > mutex_init(&nor->lock); > > - /* > - * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up > - * with the software protection bits set > - */ > - > - if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || > - JEDEC_MFR(info) == SNOR_MFR_INTEL || > - JEDEC_MFR(info) == SNOR_MFR_SST || > - info->flags & SPI_NOR_HAS_LOCK) { > - write_enable(nor); > - write_sr(nor, 0); > - spi_nor_wait_till_ready(nor); > - } > - > if (!mtd->name) > mtd->name = dev_name(dev); > mtd->priv = nor; > @@ -1447,11 +1469,6 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > > /* Quad/Dual-read mode takes precedence over fast/normal */ > if (mode == SPI_NOR_QUAD && info->flags & SPI_NOR_QUAD_READ) { > - ret = set_quad_mode(nor, info); > - if (ret) { > - dev_err(dev, "quad mode not supported\n"); > - return ret; > - } > nor->flash_read = SPI_NOR_QUAD; > } else if (mode == SPI_NOR_DUAL && info->flags & SPI_NOR_DUAL_READ) { > nor->flash_read = SPI_NOR_DUAL; > @@ -1503,8 +1520,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > /* No small sector erase for 4-byte command set */ > nor->erase_opcode = SPINOR_OP_SE_4B; > mtd->erasesize = info->sector_size; It seems that you didn't base your patch on the spi-nor tree. Before your patch, you should have something like: else if (mtd->size > 0x1000000) { /* enable 4-byte addressing if the device exceeds 16MiB */ nor->addr_width = 4; if (JEDEC_MFR(info) == SNOR_MFR_SPANSION || info->flags & SPI_NOR_4B_OPCODES) spi_nor_set_4byte_opcodes(nor, info); else set_4byte(nor, info, 1); } else { nor->addr_width = 3; } That's why in my comment of review 1, I was talking about handling the case where spi_nor_set_4byte_opcodes() is called instead of set_4byte(): indeed when the manufacturer id is Spansion or when the SPI_NOR_4B_OPCODES flag is set. Hence in spi_nor_reset(), or whatever name you choose, set_4byte() must not be called if the SPI_NOR_4B_OPCODES flag is set in info->flags. Besides, for now I don't know that much about how power management is handled by the Linux kernel, especially which events trigger the call of .suspend() or .resume(). I've started to read documentation about that topic so please be patient because I need some time to figure out the potential side effects this series may introduce. I know you test your patches before submitting them, so this is not a question of trust but I'd rather understand what patches actually do instead of blindly merge them! :) Also maybe this patch can help you: http://patchwork.ozlabs.org/patch/719777/ It's not related to power management but it also reworks spi_nor_scan() so all settings (op codes, protocols, number of dummy cycles, ...) are chosen once for all by spi_nor_init_params() then the actual memory device is configured by spi_nor_setup(). I can rework spi_nor_setup() a little bit as the first part of its code is needed to be done only once from spi_nor_scan() whereas the final part almost matches what's your "spi_nor_reset()" function will do in term. We should regroup {unlock sectors, enable_quad_io() and set_4byte() (if not set_nor_set_4byte_opcodes)} codes. That is to say, the minimum set of SPI commands we have to send to the memory at each power on. Best regards, Cyrille > - } else > - set_4byte(nor, info, 1); > + } > } else { > nor->addr_width = 3; > } > @@ -1517,6 +1533,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) > > nor->read_dummy = spi_nor_read_dummy_cycles(nor); > > + ret = spi_nor_reset(nor); > + if (ret) > + return ret; > + > dev_info(dev, "%s (%lld Kbytes)\n", info->name, > (long long)mtd->size >> 10); > > diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h > index c425c7b..4733c04 100644 > --- a/include/linux/mtd/spi-nor.h > +++ b/include/linux/mtd/spi-nor.h > @@ -121,6 +121,8 @@ enum spi_nor_option_flags { > SNOR_F_HAS_SR_TB = BIT(1), > }; > > +struct flash_info; > + > /** > * struct spi_nor - Structure for defining a the SPI NOR layer > * @mtd: point to a mtd_info structure > @@ -154,6 +156,7 @@ enum spi_nor_option_flags { > * @priv: the private data > */ > struct spi_nor { > + const struct flash_info *info; > struct mtd_info mtd; > struct mutex lock; > struct device *dev; > @@ -198,12 +201,28 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor) > } > > /** > + * spi_nor_reset() - reset scan the SPI NOR > + * @nor: the spi_nor structure > + * > + * The drivers uses this function to reset the SPI NOR flash device to > + * its initial scanned state, it shall use all nor information set on poweron > + * for the read mode, address width and enabling write mode for certain > + * manufacturers. This would be needed to be called for flash devices that are > + * reset during power management. > + * > + * The chip type name can be provided through the @name parameter. > + * > + * Return: 0 for success, others for failure. > + */ > +int spi_nor_reset(struct spi_nor *nor); > + > +/** > * spi_nor_scan() - scan the SPI NOR > * @nor: the spi_nor structure > * @name: the chip type name > * @mode: the read mode supported by the driver > * > - * The drivers can use this fuction to scan the SPI NOR. > + * The drivers can use this function to scan the SPI NOR. > * In the scanning, it will try to get all the necessary information to > * fill the mtd_info{} and the spi_nor{}. > * > -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Feb 9, 2017 at 12:49 PM, Cyrille Pitchen <cyrille.pitchen@atmel.com> wrote: > Hi Kamal, > > Le 08/02/2017 à 17:53, Kamal Dasu a écrit : >> Refactored spi_nor_scan() code to add spi_nor_reset() function that >> programs the nand device to: >> 1) remove flash protection if applicable >> 2) set read mode to quad mode if configured such >> 3) set the address width based on the flash size and vendor >> >> On pm resume spi-nor flash may need to be reconfigured after power >> reset, there is no need to go through a full spi_nor_scan(), flash >> device driver needs to call spi_nor_reset() to reprogram the flash >> to its probed state. >> >> Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> >> --- >> drivers/mtd/spi-nor/spi-nor.c | 62 ++++++++++++++++++++++++++++--------------- >> include/linux/mtd/spi-nor.h | 21 ++++++++++++++- >> 2 files changed, 61 insertions(+), 22 deletions(-) >> >> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c >> index da7cd69..8e3d8bd 100644 >> --- a/drivers/mtd/spi-nor/spi-nor.c >> +++ b/drivers/mtd/spi-nor/spi-nor.c >> @@ -1312,6 +1312,41 @@ static int spi_nor_check(struct spi_nor *nor) >> return 0; >> } >> >> +int spi_nor_reset(struct spi_nor *nor) >> +{ >> + int ret = 0; >> + const struct flash_info *info = nor->info; >> + struct device *dev = nor->dev; >> + >> + /* >> + * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up >> + * with the software protection bits set >> + */ >> + >> + if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || >> + JEDEC_MFR(info) == SNOR_MFR_INTEL || >> + JEDEC_MFR(info) == SNOR_MFR_SST || >> + info->flags & SPI_NOR_HAS_LOCK) { >> + write_enable(nor); >> + write_sr(nor, 0); >> + spi_nor_wait_till_ready(nor); >> + } >> + >> + if (nor->flash_read == SPI_NOR_QUAD) { >> + ret = set_quad_mode(nor, info); >> + if (ret) { >> + dev_err(dev, "quad mode not supported\n"); >> + return ret; >> + } >> + } >> + >> + if (nor->addr_width == 4 && JEDEC_MFR(info) != SNOR_MFR_SPANSION) >> + set_4byte(nor, info, 1); >> + >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(spi_nor_reset); >> + >> int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) >> { >> const struct flash_info *info = NULL; >> @@ -1357,22 +1392,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) >> } >> } >> >> + nor->info = info; >> mutex_init(&nor->lock); >> >> - /* >> - * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up >> - * with the software protection bits set >> - */ >> - >> - if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || >> - JEDEC_MFR(info) == SNOR_MFR_INTEL || >> - JEDEC_MFR(info) == SNOR_MFR_SST || >> - info->flags & SPI_NOR_HAS_LOCK) { >> - write_enable(nor); >> - write_sr(nor, 0); >> - spi_nor_wait_till_ready(nor); >> - } >> - >> if (!mtd->name) >> mtd->name = dev_name(dev); >> mtd->priv = nor; >> @@ -1447,11 +1469,6 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) >> >> /* Quad/Dual-read mode takes precedence over fast/normal */ >> if (mode == SPI_NOR_QUAD && info->flags & SPI_NOR_QUAD_READ) { >> - ret = set_quad_mode(nor, info); >> - if (ret) { >> - dev_err(dev, "quad mode not supported\n"); >> - return ret; >> - } >> nor->flash_read = SPI_NOR_QUAD; >> } else if (mode == SPI_NOR_DUAL && info->flags & SPI_NOR_DUAL_READ) { >> nor->flash_read = SPI_NOR_DUAL; >> @@ -1503,8 +1520,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) >> /* No small sector erase for 4-byte command set */ >> nor->erase_opcode = SPINOR_OP_SE_4B; >> mtd->erasesize = info->sector_size; > > It seems that you didn't base your patch on the spi-nor tree. Before your > patch, you should have something like: I rebased to the linus tree. I will rebase to the spi-nor tree for the next version. > > else if (mtd->size > 0x1000000) { > /* enable 4-byte addressing if the device exceeds 16MiB */ > nor->addr_width = 4; > if (JEDEC_MFR(info) == SNOR_MFR_SPANSION || > info->flags & SPI_NOR_4B_OPCODES) > spi_nor_set_4byte_opcodes(nor, info); > else > set_4byte(nor, info, 1); > } else { > nor->addr_width = 3; > } > > That's why in my comment of review 1, I was talking about handling the > case where spi_nor_set_4byte_opcodes() is called instead of set_4byte(): > indeed when the manufacturer id is Spansion or when the SPI_NOR_4B_OPCODES > flag is set. > Ok I need to use the spi-nor tree. > Hence in spi_nor_reset(), or whatever name you choose, set_4byte() must not > be called if the SPI_NOR_4B_OPCODES flag is set in info->flags. > > Besides, for now I don't know that much about how power management is > handled by the Linux kernel, especially which events trigger the call of > .suspend() or .resume(). > I've started to read documentation about that topic so please be patient > because I need some time to figure out the potential side effects this > series may introduce. > I know you test your patches before submitting them, so this is not a > question of trust but I'd rather understand what patches actually do > instead of blindly merge them! :) > I will make sure I use the right codebase. > Also maybe this patch can help you: > http://patchwork.ozlabs.org/patch/719777/ > I do see that the m25p80 and spi-nor drivers are implementing and distinguishing spi protocol and cmds based on the address width and transfer modes. And is spi-nor refactoring the same parts of the code which I have touched. so will follow up in this change. > It's not related to power management but it also reworks spi_nor_scan() > so all settings (op codes, protocols, number of dummy cycles, ...) are > chosen once for all by spi_nor_init_params() then the actual memory device > is configured by spi_nor_setup(). > > I can rework spi_nor_setup() a little bit as the first part of its code is > needed to be done only once from spi_nor_scan() whereas the final part > almost matches what's your "spi_nor_reset()" function will do in term. > > We should regroup {unlock sectors, enable_quad_io() and set_4byte() (if not > set_nor_set_4byte_opcodes)} codes. That is to say, the minimum set of SPI > commands we have to send to the memory at each power on. > Yes that sounds right. Regarding the pm do we want to use the m25p80 resume, or let the spi master somehow invoke the setup from its resume. If there was a way to do that cleanly within the current framework of m25p, spi-nor, spi master it might leave that decision to the spi controller driver. Also in our case we are a spi master controller driver mtd and spi-nor m25p80 structures and its ops are transparent. > Best regards, > > Cyrille > > >> - } else >> - set_4byte(nor, info, 1); >> + } >> } else { >> nor->addr_width = 3; >> } >> @@ -1517,6 +1533,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) >> >> nor->read_dummy = spi_nor_read_dummy_cycles(nor); >> >> + ret = spi_nor_reset(nor); >> + if (ret) >> + return ret; >> + >> dev_info(dev, "%s (%lld Kbytes)\n", info->name, >> (long long)mtd->size >> 10); >> >> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h >> index c425c7b..4733c04 100644 >> --- a/include/linux/mtd/spi-nor.h >> +++ b/include/linux/mtd/spi-nor.h >> @@ -121,6 +121,8 @@ enum spi_nor_option_flags { >> SNOR_F_HAS_SR_TB = BIT(1), >> }; >> >> +struct flash_info; >> + >> /** >> * struct spi_nor - Structure for defining a the SPI NOR layer >> * @mtd: point to a mtd_info structure >> @@ -154,6 +156,7 @@ enum spi_nor_option_flags { >> * @priv: the private data >> */ >> struct spi_nor { >> + const struct flash_info *info; >> struct mtd_info mtd; >> struct mutex lock; >> struct device *dev; >> @@ -198,12 +201,28 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor) >> } >> >> /** >> + * spi_nor_reset() - reset scan the SPI NOR >> + * @nor: the spi_nor structure >> + * >> + * The drivers uses this function to reset the SPI NOR flash device to >> + * its initial scanned state, it shall use all nor information set on poweron >> + * for the read mode, address width and enabling write mode for certain >> + * manufacturers. This would be needed to be called for flash devices that are >> + * reset during power management. >> + * >> + * The chip type name can be provided through the @name parameter. >> + * >> + * Return: 0 for success, others for failure. >> + */ >> +int spi_nor_reset(struct spi_nor *nor); >> + >> +/** >> * spi_nor_scan() - scan the SPI NOR >> * @nor: the spi_nor structure >> * @name: the chip type name >> * @mode: the read mode supported by the driver >> * >> - * The drivers can use this fuction to scan the SPI NOR. >> + * The drivers can use this function to scan the SPI NOR. >> * In the scanning, it will try to get all the necessary information to >> * fill the mtd_info{} and the spi_nor{}. >> * >> > -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index da7cd69..8e3d8bd 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -1312,6 +1312,41 @@ static int spi_nor_check(struct spi_nor *nor) return 0; } +int spi_nor_reset(struct spi_nor *nor) +{ + int ret = 0; + const struct flash_info *info = nor->info; + struct device *dev = nor->dev; + + /* + * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up + * with the software protection bits set + */ + + if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || + JEDEC_MFR(info) == SNOR_MFR_INTEL || + JEDEC_MFR(info) == SNOR_MFR_SST || + info->flags & SPI_NOR_HAS_LOCK) { + write_enable(nor); + write_sr(nor, 0); + spi_nor_wait_till_ready(nor); + } + + if (nor->flash_read == SPI_NOR_QUAD) { + ret = set_quad_mode(nor, info); + if (ret) { + dev_err(dev, "quad mode not supported\n"); + return ret; + } + } + + if (nor->addr_width == 4 && JEDEC_MFR(info) != SNOR_MFR_SPANSION) + set_4byte(nor, info, 1); + + return ret; +} +EXPORT_SYMBOL_GPL(spi_nor_reset); + int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) { const struct flash_info *info = NULL; @@ -1357,22 +1392,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) } } + nor->info = info; mutex_init(&nor->lock); - /* - * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up - * with the software protection bits set - */ - - if (JEDEC_MFR(info) == SNOR_MFR_ATMEL || - JEDEC_MFR(info) == SNOR_MFR_INTEL || - JEDEC_MFR(info) == SNOR_MFR_SST || - info->flags & SPI_NOR_HAS_LOCK) { - write_enable(nor); - write_sr(nor, 0); - spi_nor_wait_till_ready(nor); - } - if (!mtd->name) mtd->name = dev_name(dev); mtd->priv = nor; @@ -1447,11 +1469,6 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) /* Quad/Dual-read mode takes precedence over fast/normal */ if (mode == SPI_NOR_QUAD && info->flags & SPI_NOR_QUAD_READ) { - ret = set_quad_mode(nor, info); - if (ret) { - dev_err(dev, "quad mode not supported\n"); - return ret; - } nor->flash_read = SPI_NOR_QUAD; } else if (mode == SPI_NOR_DUAL && info->flags & SPI_NOR_DUAL_READ) { nor->flash_read = SPI_NOR_DUAL; @@ -1503,8 +1520,7 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) /* No small sector erase for 4-byte command set */ nor->erase_opcode = SPINOR_OP_SE_4B; mtd->erasesize = info->sector_size; - } else - set_4byte(nor, info, 1); + } } else { nor->addr_width = 3; } @@ -1517,6 +1533,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, enum read_mode mode) nor->read_dummy = spi_nor_read_dummy_cycles(nor); + ret = spi_nor_reset(nor); + if (ret) + return ret; + dev_info(dev, "%s (%lld Kbytes)\n", info->name, (long long)mtd->size >> 10); diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index c425c7b..4733c04 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -121,6 +121,8 @@ enum spi_nor_option_flags { SNOR_F_HAS_SR_TB = BIT(1), }; +struct flash_info; + /** * struct spi_nor - Structure for defining a the SPI NOR layer * @mtd: point to a mtd_info structure @@ -154,6 +156,7 @@ enum spi_nor_option_flags { * @priv: the private data */ struct spi_nor { + const struct flash_info *info; struct mtd_info mtd; struct mutex lock; struct device *dev; @@ -198,12 +201,28 @@ static inline struct device_node *spi_nor_get_flash_node(struct spi_nor *nor) } /** + * spi_nor_reset() - reset scan the SPI NOR + * @nor: the spi_nor structure + * + * The drivers uses this function to reset the SPI NOR flash device to + * its initial scanned state, it shall use all nor information set on poweron + * for the read mode, address width and enabling write mode for certain + * manufacturers. This would be needed to be called for flash devices that are + * reset during power management. + * + * The chip type name can be provided through the @name parameter. + * + * Return: 0 for success, others for failure. + */ +int spi_nor_reset(struct spi_nor *nor); + +/** * spi_nor_scan() - scan the SPI NOR * @nor: the spi_nor structure * @name: the chip type name * @mode: the read mode supported by the driver * - * The drivers can use this fuction to scan the SPI NOR. + * The drivers can use this function to scan the SPI NOR. * In the scanning, it will try to get all the necessary information to * fill the mtd_info{} and the spi_nor{}. *
Refactored spi_nor_scan() code to add spi_nor_reset() function that programs the nand device to: 1) remove flash protection if applicable 2) set read mode to quad mode if configured such 3) set the address width based on the flash size and vendor On pm resume spi-nor flash may need to be reconfigured after power reset, there is no need to go through a full spi_nor_scan(), flash device driver needs to call spi_nor_reset() to reprogram the flash to its probed state. Signed-off-by: Kamal Dasu <kdasu.kdev@gmail.com> --- drivers/mtd/spi-nor/spi-nor.c | 62 ++++++++++++++++++++++++++++--------------- include/linux/mtd/spi-nor.h | 21 ++++++++++++++- 2 files changed, 61 insertions(+), 22 deletions(-)