Re: [PATCH v4 14/20] mtd: nand: qcom: add command elements in BAM transaction

[Archit Taneja <architt@codeaurora.org>]

On 08/11/2017 05:09 PM, 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@codeaurora.org>

Thanks,
Archit

> 
> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> ---
>   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 c0c140b..d17c466 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
> @@ -196,6 +197,7 @@
>   /* Returns the actual register address for NAND_FLASH_DEV_* */
>   #define nandc_dev_addr(nandc, reg) ((nandc)->props->flash_dev_offset + (reg))
>   
> +#define QPIC_PER_CW_CMD_ELEMENTS	32
>   #define QPIC_PER_CW_CMD_SGL		32
>   #define QPIC_PER_CW_DATA_SGL		8
>   
> @@ -215,8 +217,13 @@
>   /*
>    * 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.
> @@ -225,8 +232,11 @@
>    * @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;
> @@ -456,7 +466,8 @@ 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);
> @@ -466,6 +477,10 @@ 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;
> @@ -483,6 +498,8 @@ 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;
> 

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