Re: [PATCH V3] mtd: rawnand: qcom: update last code word register

From: Manivannan Sadhasivam
Date: Thu Jan 14 2021 - 11:32:43 EST

On Thu, Jan 14, 2021 at 04:53:25PM +0100, Miquel Raynal wrote:
> Hello,
>
> Md Sadre Alam <mdalam@xxxxxxxxxxxxxx> wrote on Sun, 10 Jan 2021
> 09:31:45 +0530:
>
> > From QPIC version 2.0 onwards new register got added to
>
> a
>
> > read last codeword. This change will update the same.
>
> the? ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> Please reword this sentence.
>
> > For first three code word READ_LOCATION_n register will be
> > use.For last code word READ_LOCATION_LAST_CW_n register will be
> > use.
>
> "For the first three codewords, READ_LOCATION_n registers will be used.
> The last codeword register will be accessed through
> READ_LOCATION_LAST_CW_n."
>
> Also, please specify what these registers store.
>
> > Signed-off-by: Md Sadre Alam <mdalam@xxxxxxxxxxxxxx>
>
> Could someone please test this patch?
>

This is on my TODO list. Will get back to it once I'm back from holidays
or sooner if I find some time in the middle.

Thanks,
Mani

> > ---
> > [V3]
> > * Added else condition for last code word in update_rw_regs().
> > drivers/mtd/nand/raw/qcom_nandc.c | 84 ++++++++++++++++++++++++++++++++-------
> > 1 file changed, 70 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> > index 667e4bf..50ff6e3 100644
> > --- a/drivers/mtd/nand/raw/qcom_nandc.c
> > +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> > @@ -48,6 +48,10 @@
> > #define NAND_READ_LOCATION_1 0xf24
> > #define NAND_READ_LOCATION_2 0xf28
> > #define NAND_READ_LOCATION_3 0xf2c
> > +#define NAND_READ_LOCATION_LAST_CW_0 0xf40
> > +#define NAND_READ_LOCATION_LAST_CW_1 0xf44
> > +#define NAND_READ_LOCATION_LAST_CW_2 0xf48
> > +#define NAND_READ_LOCATION_LAST_CW_3 0xf4c
> >
> > /* dummy register offsets, used by write_reg_dma */
> > #define NAND_DEV_CMD1_RESTORE 0xdead
> > @@ -187,6 +191,12 @@ nandc_set_reg(nandc, NAND_READ_LOCATION_##reg, \
> > ((size) << READ_LOCATION_SIZE) | \
> > ((is_last) << READ_LOCATION_LAST))
> >
> > +#define nandc_set_read_loc_last(nandc, reg, offset, size, is_last) \
> > +nandc_set_reg(nandc, NAND_READ_LOCATION_LAST_CW_##reg, \
> > + ((offset) << READ_LOCATION_OFFSET) | \
> > + ((size) << READ_LOCATION_SIZE) | \
> > + ((is_last) << READ_LOCATION_LAST))
> > +
> > /*
> > * Returns the actual register address for all NAND_DEV_ registers
> > * (i.e. NAND_DEV_CMD0, NAND_DEV_CMD1, NAND_DEV_CMD2 and NAND_DEV_CMD_VLD)
> > @@ -316,6 +326,10 @@ struct nandc_regs {
> > __le32 read_location1;
> > __le32 read_location2;
> > __le32 read_location3;
> > + __le32 read_location_last0;
> > + __le32 read_location_last1;
> > + __le32 read_location_last2;
> > + __le32 read_location_last3;
> >
> > __le32 erased_cw_detect_cfg_clr;
> > __le32 erased_cw_detect_cfg_set;
> > @@ -644,6 +658,14 @@ static __le32 *offset_to_nandc_reg(struct nandc_regs *regs, int offset)
> > return &regs->read_location2;
> > case NAND_READ_LOCATION_3:
> > return &regs->read_location3;
> > + case NAND_READ_LOCATION_LAST_CW_0:
> > + return &regs->read_location_last0;
> > + case NAND_READ_LOCATION_LAST_CW_1:
> > + return &regs->read_location_last1;
> > + case NAND_READ_LOCATION_LAST_CW_2:
> > + return &regs->read_location_last2;
> > + case NAND_READ_LOCATION_LAST_CW_3:
> > + return &regs->read_location_last3;
> > default:
> > return NULL;
> > }
> > @@ -719,9 +741,14 @@ static void update_rw_regs(struct qcom_nand_host *host, int num_cw, bool read)
> > nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
> > nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
> >
> > - if (read)
> > - nandc_set_read_loc(nandc, 0, 0, host->use_ecc ?
> > - host->cw_data : host->cw_size, 1);
> > + if (read) {
> > + if (nandc->props->qpic_v2)
> > + nandc_set_read_loc_last(nandc, 0, 0, host->use_ecc ?
> > + host->cw_data : host->cw_size, 1);
> > + else
> > + nandc_set_read_loc(nandc, 0, 0, host->use_ecc ?
> > + host->cw_data : host->cw_size, 1);
> > + }
> > }
> >
> > /*
> > @@ -1096,9 +1123,13 @@ static void config_nand_page_read(struct qcom_nand_controller *nandc)
> > static void
> > config_nand_cw_read(struct qcom_nand_controller *nandc, bool use_ecc)
> > {
> > - if (nandc->props->is_bam)
> > + if (nandc->props->is_bam) {
> > + if (nandc->props->qpic_v2)
> > + write_reg_dma(nandc, NAND_READ_LOCATION_LAST_CW_0,
> > + 1, NAND_BAM_NEXT_SGL);
> > write_reg_dma(nandc, NAND_READ_LOCATION_0, 4,
> > NAND_BAM_NEXT_SGL);
> > + }
> >
> > write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> > write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> > @@ -1633,16 +1664,28 @@ qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
> > }
> >
> > if (nandc->props->is_bam) {
> > - nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0);
> > + if (nandc->props->qpic_v2 && cw == (ecc->steps - 1))
> > + nandc_set_read_loc_last(nandc, 0, read_loc, data_size1, 0);
> > + else
> > + nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0);
>
> You repeat many times this logic, a helper to avoid this extra
> indentation level with the if/else block is needed.
>
> > read_loc += data_size1;
> >
> > - nandc_set_read_loc(nandc, 1, read_loc, oob_size1, 0);
> > + if (nandc->props->qpic_v2 && cw == (ecc->steps - 1))
> > + nandc_set_read_loc_last(nandc, 1, read_loc, oob_size1, 0);
> > + else
> > + nandc_set_read_loc(nandc, 1, read_loc, oob_size1, 0);
> > read_loc += oob_size1;
> >
> > - nandc_set_read_loc(nandc, 2, read_loc, data_size2, 0);
> > + if (nandc->props->qpic_v2 && cw == (ecc->steps - 1))
> > + nandc_set_read_loc_last(nandc, 2, read_loc, data_size2, 0);
> > + else
> > + nandc_set_read_loc(nandc, 2, read_loc, data_size2, 0);
> > read_loc += data_size2;
> >
> > - nandc_set_read_loc(nandc, 3, read_loc, oob_size2, 1);
> > + if (nandc->props->qpic_v2 && cw == (ecc->steps - 1))
> > + nandc_set_read_loc_last(nandc, 3, read_loc, oob_size2, 0);
> > + else
> > + nandc_set_read_loc(nandc, 3, read_loc, oob_size2, 1);
> > }
>
> Thanks,
> Miquèl