Re: [PATCH v2 1/1] mtd: nand: pxa3xx: Set FORCE_CSX bit to ARMADA370 variants.

From: Miquel RAYNAL
Date: Wed Sep 27 2017 - 02:53:28 EST


Hello Kalyan,

On Wed, 27 Sep 2017 13:55:16 +1300
Kalyan Kinthada <kalyan.kinthada@xxxxxxxxxxxxxxxxxxx> wrote:

> When the arbitration between NOR and NAND flash is enabled
> the <FORCE_CSX> field bit[21] in the Data Flash Control Register
> needs to be set to 1 according to guidleine GL-5830741.
>
> This commit sets the FORCE_CSX bit to 1 for all
> ARMADA370 variants as the arbitration is always enabled by default.

Maybe you could mention here that this does not apply for pxa3xx
variant as this bit does not exist/is reserved on the NFCv1.

>
> Signed-off-by: Kalyan Kinthada <kalyan.kinthada@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/mtd/nand/pxa3xx_nand.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/mtd/nand/pxa3xx_nand.c
> b/drivers/mtd/nand/pxa3xx_nand.c index 85cff68643e0..b2753eea567c
> 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c
> +++ b/drivers/mtd/nand/pxa3xx_nand.c
> @@ -68,6 +68,7 @@
> #define NDCR_PAGE_SZ (0x1 << 24)
> #define NDCR_NCSX (0x1 << 23)
> #define NDCR_ND_MODE (0x3 << 21)
> +#define NDCR_FORCE_CSX (0x1 << 21)
> #define NDCR_NAND_MODE (0x0)

The three lines above seems to have the same purpose.
I had a look to the specs (pxa/370/375/xp/380/390), and I could
not find any reference to a valid bit 22 in NDCR (it is always
reserved). Maybe you could delete NDCR_ND_MODE and
NDCR_NAND_MODE then ?

> #define NDCR_CLR_PG_CNT (0x1 << 20)
> #define NFCV1_NDCR_ARB_CNTL (0x1 << 19)
> @@ -1464,6 +1465,9 @@ static int pxa3xx_nand_config_ident(struct
> pxa3xx_nand_info *info) info->chunk_size = PAGE_CHUNK_SIZE;
> info->reg_ndcr = 0x0; /* enable all interrupts */
> info->reg_ndcr |= (pdata->enable_arbiter) ? NDCR_ND_ARB_EN :
> 0;
> + /* Set FORCE_CSX bit for all ARMADAGL-5830741370 Variants.
> Ref#: GL-5830741*/

You miss a space between "GL-5830741" and "*/".

> + if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370)
> + info->reg_ndcr |= NDCR_FORCE_CSX;
> info->reg_ndcr |= NDCR_RD_ID_CNT(READ_ID_BYTES);
> info->reg_ndcr |= NDCR_SPARE_EN;
>
> @@ -1498,6 +1502,9 @@ static void pxa3xx_nand_detect_config(struct
> pxa3xx_nand_info *info) info->reg_ndcr = ndcr &
> ~(NDCR_INT_MASK | NDCR_ND_ARB_EN |
> NFCV1_NDCR_ARB_CNTL); info->reg_ndcr |= (pdata->enable_arbiter) ?
> NDCR_ND_ARB_EN : 0;
> + /* Set FORCE_CSX bit for all ARMADA370 Variants. Ref#:
> GL-5830741*/

Same here.

> + if (info->variant == PXA3XX_NAND_VARIANT_ARMADA370)
> + info->reg_ndcr |= NDCR_FORCE_CSX;
> info->ndtr0cs0 = nand_readl(info, NDTR0CS0);
> info->ndtr1cs0 = nand_readl(info, NDTR1CS0);
> }


Thanks,
MiquÃl

--
Miquel Raynal, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com