Re: [PATCH v5 10/16] mtd: nand: qcom: add command elements in BAM transaction

[Abhishek Sahu]

On 2017-08-17 17:37, Abhishek Sahu wrote:
> All the QPIC register read/write through BAM DMA requires
> command descriptor which contains the array of command elements.
>
> Reviewed-by: Archit Taneja <architt@xxxxxxxxxxxxxx>
> Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx>
> ---
>
> * Changes from v4: None
>
> * BUILD DEPENDENCY:
>
>   This PATCH has build dependency over following BAM command descriptor
>   patch posted in DMA engine mailing list
>
>   http://www.spinics.net/lists/dmaengine/msg13665.html

 Hi Boris,

 These patch has build dependency over DMA engine patch
 http://www.spinics.net/lists/dmaengine/msg13665.html

 but this patch has been applied in your github
 https://github.com/bbrezillon/linux-0day/commits/nand/next

 The DMA change has not merged yet so could we drop this and
 next patch alone till the the DMA change is merged to prevent
 build error.

 Rest of the patch can go without any build or functionality
 failure.

 Thanks,
 Abhishek

>  drivers/mtd/nand/qcom_nandc.c | 19 ++++++++++++++++++-
>  1 file changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/qcom_nandc.c 
> b/drivers/mtd/nand/qcom_nandc.c
> index 7977a70..b0a4734 100644
> --- a/drivers/mtd/nand/qcom_nandc.c
> +++ b/drivers/mtd/nand/qcom_nandc.c
> @@ -22,6 +22,7 @@
>  #include <linux/of.h>
>  #include <linux/of_device.h>
>  #include <linux/delay.h>
> +#include <linux/dma/qcom_bam_dma.h>
>
>  /* NANDc reg offsets */
>  #define	NAND_FLASH_CMD			0x00
> @@ -199,6 +200,7 @@
>   */
>  #define dev_cmd_reg_addr(nandc, reg)
> ((nandc)->props->dev_cmd_reg_start + (reg))
>
> +#define QPIC_PER_CW_CMD_ELEMENTS	32
>  #define QPIC_PER_CW_CMD_SGL		32
>  #define QPIC_PER_CW_DATA_SGL		8
>
> @@ -221,8 +223,13 @@
>  /*
>   * This data type corresponds to the BAM transaction which will be 
> used for all
>   * NAND transfers.
> + * @bam_ce - the array of BAM command elements
>   * @cmd_sgl - sgl for NAND BAM command pipe
>   * @data_sgl - sgl for NAND BAM consumer/producer pipe
> + * @bam_ce_pos - the index in bam_ce which is available for next sgl
> + * @bam_ce_start - the index in bam_ce which marks the start position 
> ce
> + *		   for current sgl. It will be used for size calculation
> + *		   for current sgl
>   * @cmd_sgl_pos - current index in command sgl.
>   * @cmd_sgl_start - start index in command sgl.
>   * @tx_sgl_pos - current index in data sgl for tx.
> @@ -231,8 +238,11 @@
>   * @rx_sgl_start - start index in data sgl for rx.
>   */
>  struct bam_transaction {
> +	struct bam_cmd_element *bam_ce;
>  	struct scatterlist *cmd_sgl;
>  	struct scatterlist *data_sgl;
> +	u32 bam_ce_pos;
> +	u32 bam_ce_start;
>  	u32 cmd_sgl_pos;
>  	u32 cmd_sgl_start;
>  	u32 tx_sgl_pos;
> @@ -462,7 +472,8 @@ static void free_bam_transaction(struct
> qcom_nand_controller *nandc)
>
>  	bam_txn_size =
>  		sizeof(*bam_txn) + num_cw *
> -		((sizeof(*bam_txn->cmd_sgl) * QPIC_PER_CW_CMD_SGL) +
> +		((sizeof(*bam_txn->bam_ce) * QPIC_PER_CW_CMD_ELEMENTS) +
> +		(sizeof(*bam_txn->cmd_sgl) * QPIC_PER_CW_CMD_SGL) +
>  		(sizeof(*bam_txn->data_sgl) * QPIC_PER_CW_DATA_SGL));
>
>  	bam_txn_buf = devm_kzalloc(nandc->dev, bam_txn_size, GFP_KERNEL);
> @@ -472,6 +483,10 @@ static void free_bam_transaction(struct
> qcom_nand_controller *nandc)
>  	bam_txn = bam_txn_buf;
>  	bam_txn_buf += sizeof(*bam_txn);
>
> +	bam_txn->bam_ce = bam_txn_buf;
> +	bam_txn_buf +=
> +		sizeof(*bam_txn->bam_ce) * QPIC_PER_CW_CMD_ELEMENTS * num_cw;
> +
>  	bam_txn->cmd_sgl = bam_txn_buf;
>  	bam_txn_buf +=
>  		sizeof(*bam_txn->cmd_sgl) * QPIC_PER_CW_CMD_SGL * num_cw;
> @@ -489,6 +504,8 @@ static void clear_bam_transaction(struct
> qcom_nand_controller *nandc)
>  	if (!nandc->props->is_bam)
>  		return;
>
> +	bam_txn->bam_ce_pos = 0;
> +	bam_txn->bam_ce_start = 0;
>  	bam_txn->cmd_sgl_pos = 0;
>  	bam_txn->cmd_sgl_start = 0;
>  	bam_txn->tx_sgl_pos = 0;