| Message ID | 1402579245-13377-6-git-send-email-LW@KARO-electronics.de |
|---|---|
| State | Changes Requested |
| Headers | show |
Hi Lothar, On Thu, Jun 12, 2014 at 03:20:45PM +0200, Lothar Waßmann wrote: > Without blockmark swapping, there is no use in creating a BBT from > scratch, so use a BBT descriptor with NAND_BBT_CREATE unset in this > case. I'm curious: what is your plan if there is no BBT available on your device, or if it ever gets corrupted? IIUC, nand_bbt will just assume you have no bad blocks, and it will never write a bad block table to flash. This also means no subsequent discoverable bad blocks can be recorded across power cycles, I believe. Maybe you don't want to specify your own nand_bbt_descr's at all, but you just need to set: chip->bbt_options |= NAND_BBT_CREATE_EMPTY | NAND_BBT_NO_OOB; (Note: there's a little bit of fuzziness about NAND_BBT_* flags, where some are targeted for the nand_chip::bbt_options field, and others belong in struct nand_bbt_descr::options.) But if for some reason we need to keep this patch, a comment below: > Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> > --- > drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 28 +++++++++++++++++++++++++++- > 1 file changed, 27 insertions(+), 1 deletion(-) > > diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > index 37537b4..fc710d7 100644 > --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > @@ -43,6 +43,29 @@ static struct nand_bbt_descr gpmi_bbt_descr = { > .pattern = scan_ff_pattern > }; > > +static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' }; > +static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' }; > + > +static struct nand_bbt_descr bbt_main_no_oob_descr = { > + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | > + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | > + NAND_BBT_NO_OOB, Please indent the above two lines a bit, preferably matching the indentation of NAND_BBT_LASTBLOCK. It should be clear that this is a continuation of the '.options' initialization. > + .len = 4, > + .veroffs = 4, > + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, > + .pattern = bbt_pattern, > +}; > + > +static struct nand_bbt_descr bbt_mirror_no_oob_descr = { > + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | > + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | > + NAND_BBT_NO_OOB, Same here. > + .len = 4, > + .veroffs = 4, > + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, > + .pattern = mirror_pattern, > +}; > + > /* > * We may change the layout if we can get the ECC info from the datasheet, > * else we will use all the (page + OOB). > @@ -1728,8 +1751,11 @@ static int gpmi_nand_init(struct gpmi_nand_data *this) > chip->bbt_options |= NAND_BBT_NO_OOB_BBM; > > if (of_property_read_bool(this->dev->of_node, > - "fsl,no-blockmark-swap")) > + "fsl,no-blockmark-swap")) { > this->swap_block_mark = false; > + chip->bbt_td = &bbt_main_no_oob_descr; > + chip->bbt_md = &bbt_mirror_no_oob_descr; My initial recommendation for this patch and the previous patch means that you could just drop both patches and replace them with the following: /* Comment here to explain why... */ chip->bbt_options |= NAND_BBT_CREATE_EMPTY | NAND_BBT_NO_OOB | NAND_BBT_NO_OOB_BBM; > + } > } > dev_dbg(this->dev, "Blockmark swapping %sabled\n", > this->swap_block_mark ? "en" : "dis"); Brian
Hi, Brian Norris wrote: > Hi Lothar, > > On Thu, Jun 12, 2014 at 03:20:45PM +0200, Lothar Waßmann wrote: > > Without blockmark swapping, there is no use in creating a BBT from > > scratch, so use a BBT descriptor with NAND_BBT_CREATE unset in this > > case. > > I'm curious: what is your plan if there is no BBT available on your > device, or if it ever gets corrupted? IIUC, nand_bbt will just assume > you have no bad blocks, and it will never write a bad block table to > flash. This also means no subsequent discoverable bad blocks can be > recorded across power cycles, I believe. > That won't happen (unless it's not possible to create a BBT because all the possible blocks for the BBT are bad), because the bootloader will have created one before Linux is started. > Maybe you don't want to specify your own nand_bbt_descr's at all, but > you just need to set: > > chip->bbt_options |= NAND_BBT_CREATE_EMPTY | NAND_BBT_NO_OOB; > > (Note: there's a little bit of fuzziness about NAND_BBT_* flags, where > some are targeted for the nand_chip::bbt_options field, and others > belong in struct nand_bbt_descr::options.) > > But if for some reason we need to keep this patch, a comment below: > > > Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> > > --- > > drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 28 +++++++++++++++++++++++++++- > > 1 file changed, 27 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > > index 37537b4..fc710d7 100644 > > --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > > +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c > > @@ -43,6 +43,29 @@ static struct nand_bbt_descr gpmi_bbt_descr = { > > .pattern = scan_ff_pattern > > }; > > > > +static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' }; > > +static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' }; > > + > > +static struct nand_bbt_descr bbt_main_no_oob_descr = { > > + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | > > + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | > > + NAND_BBT_NO_OOB, > > Please indent the above two lines a bit, preferably matching the > indentation of NAND_BBT_LASTBLOCK. It should be clear that this is a > continuation of the '.options' initialization. > OK. > > + .len = 4, > > + .veroffs = 4, > > + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, > > + .pattern = bbt_pattern, > > +}; > > + > > +static struct nand_bbt_descr bbt_mirror_no_oob_descr = { > > + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | > > + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | > > + NAND_BBT_NO_OOB, > > Same here. > > > + .len = 4, > > + .veroffs = 4, > > + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, > > + .pattern = mirror_pattern, > > +}; > > + > > /* > > * We may change the layout if we can get the ECC info from the datasheet, > > * else we will use all the (page + OOB). > > @@ -1728,8 +1751,11 @@ static int gpmi_nand_init(struct gpmi_nand_data *this) > > chip->bbt_options |= NAND_BBT_NO_OOB_BBM; > > > > if (of_property_read_bool(this->dev->of_node, > > - "fsl,no-blockmark-swap")) > > + "fsl,no-blockmark-swap")) { > > this->swap_block_mark = false; > > + chip->bbt_td = &bbt_main_no_oob_descr; > > + chip->bbt_md = &bbt_mirror_no_oob_descr; > > My initial recommendation for this patch and the previous patch means > that you could just drop both patches and replace them with the > following: > > /* Comment here to explain why... */ > chip->bbt_options |= NAND_BBT_CREATE_EMPTY | > NAND_BBT_NO_OOB | > NAND_BBT_NO_OOB_BBM; OK. Lothar Waßmann
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c index 37537b4..fc710d7 100644 --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c @@ -43,6 +43,29 @@ static struct nand_bbt_descr gpmi_bbt_descr = { .pattern = scan_ff_pattern }; +static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' }; +static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' }; + +static struct nand_bbt_descr bbt_main_no_oob_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | + NAND_BBT_NO_OOB, + .len = 4, + .veroffs = 4, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = bbt_pattern, +}; + +static struct nand_bbt_descr bbt_mirror_no_oob_descr = { + .options = NAND_BBT_LASTBLOCK | NAND_BBT_WRITE | + NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP | + NAND_BBT_NO_OOB, + .len = 4, + .veroffs = 4, + .maxblocks = NAND_BBT_SCAN_MAXBLOCKS, + .pattern = mirror_pattern, +}; + /* * We may change the layout if we can get the ECC info from the datasheet, * else we will use all the (page + OOB). @@ -1728,8 +1751,11 @@ static int gpmi_nand_init(struct gpmi_nand_data *this) chip->bbt_options |= NAND_BBT_NO_OOB_BBM; if (of_property_read_bool(this->dev->of_node, - "fsl,no-blockmark-swap")) + "fsl,no-blockmark-swap")) { this->swap_block_mark = false; + chip->bbt_td = &bbt_main_no_oob_descr; + chip->bbt_md = &bbt_mirror_no_oob_descr; + } } dev_dbg(this->dev, "Blockmark swapping %sabled\n", this->swap_block_mark ? "en" : "dis");
Without blockmark swapping, there is no use in creating a BBT from scratch, so use a BBT descriptor with NAND_BBT_CREATE unset in this case. Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de> --- drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-)