Re: [PATCH v2] spi: spi-fsl-dspi: Add DMA support for Vybrid

[Mark Brown]

On Mon, Oct 17, 2016 at 11:53:08AM +0530, maitysancha...@gmail.com wrote:
> Hello,
> 
> Ping?

Please don't send content free pings and please allow a reasonable time
for review.  People get busy, go on holiday, attend conferences and so 
on so unless there is some reason for urgency (like critical bug fixes)
please allow at least a couple of weeks for review.  If there have been
review comments then people may be waiting for those to be addressed.
Sending content free pings just adds to the mail volume (if they are
seen at all) and if something has gone wrong you'll have to resend the
patches anyway.

Please don't top post, reply in line with needed context.  This allows
readers to readily follow the flow of conversation and understand what
you are talking about and also helps ensure that everything in the
discussion is being addressed.


signature.asc
Description: PGP signature

Re: [PATCH v2] spi: spi-fsl-dspi: Add DMA support for Vybrid

[maitysanchayan]

Hello,

Ping?

Regards,
Sanchayan.

On 16-10-04 16:28:33, Sanchayan Maity wrote:
> Add DMA support for Vybrid.
> 
> Signed-off-by: Sanchayan Maity 
> ---
> Changes since v1:
> - Change in the dspi_dma_xfer function. Use more apt DSPI_FIFO_SIZE
> instead of sizeof(u32)
> - Do not set RSER on every iteration of loop
> 
> Tested on Toradex Colibri Vybrid VF61 module with spi based MCP CAN 251x
> and spidev using RX/TX loopback and based on shawn's for-next branch
> currently at 4.8-rc1.
> 
> Regards,
> Sanchayan.
> ---
>  drivers/spi/spi-fsl-dspi.c | 291 
> +
>  1 file changed, 291 insertions(+)
> 
> diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
> index 9e9dadb..0f81075 100644
> --- a/drivers/spi/spi-fsl-dspi.c
> +++ b/drivers/spi/spi-fsl-dspi.c
> @@ -15,6 +15,8 @@
>  
>  #include 
>  #include 
> +#include 
> +#include 
>  #include 
>  #include 
>  #include 
> @@ -40,6 +42,7 @@
>  #define TRAN_STATE_WORD_ODD_NUM  0x04
>  
>  #define DSPI_FIFO_SIZE   4
> +#define DSPI_DMA_BUFSIZE (DSPI_FIFO_SIZE * 1024)
>  
>  #define SPI_MCR  0x00
>  #define SPI_MCR_MASTER   (1 << 31)
> @@ -71,6 +74,11 @@
>  #define SPI_SR_EOQF  0x1000
>  #define SPI_SR_TCFQF 0x8000
>  
> +#define SPI_RSER_TFFFE   BIT(25)
> +#define SPI_RSER_TFFFD   BIT(24)
> +#define SPI_RSER_RFDFE   BIT(17)
> +#define SPI_RSER_RFDFD   BIT(16)
> +
>  #define SPI_RSER 0x30
>  #define SPI_RSER_EOQFE   0x1000
>  #define SPI_RSER_TCFQE   0x8000
> @@ -108,6 +116,8 @@
>  
>  #define SPI_TCR_TCNT_MAX 0x1
>  
> +#define DMA_COMPLETION_TIMEOUT   msecs_to_jiffies(3000)
> +
>  struct chip_data {
>   u32 mcr_val;
>   u32 ctar_val;
> @@ -117,6 +127,7 @@ struct chip_data {
>  enum dspi_trans_mode {
>   DSPI_EOQ_MODE = 0,
>   DSPI_TCFQ_MODE,
> + DSPI_DMA_MODE,
>  };
>  
>  struct fsl_dspi_devtype_data {
> @@ -139,6 +150,22 @@ static const struct fsl_dspi_devtype_data ls2085a_data = 
> {
>   .max_clock_factor = 8,
>  };
>  
> +struct fsl_dspi_dma {
> + u32 curr_xfer_len;
> +
> + u32 *tx_dma_buf;
> + struct dma_chan *chan_tx;
> + dma_addr_t tx_dma_phys;
> + struct completion cmd_tx_complete;
> + struct dma_async_tx_descriptor *tx_desc;
> +
> + u32 *rx_dma_buf;
> + struct dma_chan *chan_rx;
> + dma_addr_t rx_dma_phys;
> + struct completion cmd_rx_complete;
> + struct dma_async_tx_descriptor *rx_desc;
> +};
> +
>  struct fsl_dspi {
>   struct spi_master   *master;
>   struct platform_device  *pdev;
> @@ -165,6 +192,7 @@ struct fsl_dspi {
>   u32 waitflags;
>  
>   u32 spi_tcnt;
> + struct fsl_dspi_dma *dma;
>  };
>  
>  static inline int is_double_byte_mode(struct fsl_dspi *dspi)
> @@ -368,6 +396,259 @@ static void dspi_tcfq_read(struct fsl_dspi *dspi)
>   dspi_data_from_popr(dspi, rx_word);
>  }
>  
> +static void dspi_tx_dma_callback(void *arg)
> +{
> + struct fsl_dspi *dspi = arg;
> + struct fsl_dspi_dma *dma = dspi->dma;
> +
> + complete(&dma->cmd_tx_complete);
> +}
> +
> +static void dspi_rx_dma_callback(void *arg)
> +{
> + struct fsl_dspi *dspi = arg;
> + struct fsl_dspi_dma *dma = dspi->dma;
> + int rx_word;
> + int i, len;
> + u16 d;
> +
> + rx_word = is_double_byte_mode(dspi);
> +
> + len = rx_word ? (dma->curr_xfer_len / 2) : dma->curr_xfer_len;
> +
> + if (!(dspi->dataflags & TRAN_STATE_RX_VOID)) {
> + for (i = 0; i < len; i++) {
> + d = dspi->dma->rx_dma_buf[i];
> + rx_word ? (*(u16 *)dspi->rx = d) :
> + (*(u8 *)dspi->rx = d);
> + dspi->rx += rx_word + 1;
> + }
> + }
> +
> + complete(&dma->cmd_rx_complete);
> +}
> +
> +static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
> +{
> + struct fsl_dspi_dma *dma = dspi->dma;
> + struct device *dev = &dspi->pdev->dev;
> + int time_left;
> + int tx_word;
> + int i, len;
> + u16 val;
> +
> + tx_word = is_double_byte_mode(dspi);
> +
> + len = tx_word ? (dma->curr_xfer_len / 2) : dma->curr_xfer_len;
> +
> + for (i = 0; i < len - 1; i++) {
> + val = tx_word ? *(u16 *) dspi->tx : *(u8 *) dspi->tx;
> + dspi->dma->tx_dma_buf[i] =
> + SPI_PUSHR_TXDATA(val) | SPI_PUSHR_PCS(dspi->cs) |
> + SPI_PUSHR_CTAS(0) | SPI_PUSHR_CONT;
> + dspi->tx += tx_word + 1;
> + }
> +
> + val = tx_word ? *(u16 *) dspi->tx : *(u8 *) dspi->tx;
> + dspi->dma->tx_dma_buf[i] = SPI_PUSHR_TXDATA(val) |
> + SPI_PUSHR_PCS(dspi->cs) |
> + SPI_PUSHR_CTAS(0);
> + dspi->tx += tx_word + 1;
> +
> + d