Re: [PATCH v1 4/6] dmaengine: dw-edma: Move HDMA_V0_MAX_NR_CH definition to edma.h

[Serge Semin]

Hi Mrinmay

On Fri, Jan 19, 2024 at 06:30:20PM +0530, Mrinmay Sarkar wrote:
> From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> 
> To maintain uniformity with eDMA, let's move the HDMA max channel
> definition to edma.h. While at it, let's also rename it to HDMA_MAX_NR_CH.

First of all include/linux/dma/edma.h already contains the common DW
EDMA and _HDMA_ settings/entities including the number of channels.
Both of these IP-cores have the same constraints on the max amount of
channels. Moreover the EDMA_MAX_WR_CH/EDMA_MAX_RD_CH macros are
already utilized in the common dw_edma_probe() method. So to speak you
can freely use these macros for HDMA too. Thus this change is
redundant. So is the patches 1/6 and 2/6.

Note currently all the common DW EDMA driver code uses the EDMA_/edma_
prefixes. HDMA_/hdma_ prefixes are utilized in the Native
HDMA-specific module only. So if you wished to provide some IP-core
specific settings utilized in the common part of the driver, then the
best approach would be to provide a change for the entire driver
interface (for instance first convert it to having a neutral prefixes,
like xdma_/etc, and then use the IP-core specific ones). So please
just use the EDMA_MAX_WR_CH and EDMA_MAX_RD_CH macros and drop the
patches 1, 2, and 4.

-Serge(y)

> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Signed-off-by: Mrinmay Sarkar <quic_msarkar@xxxxxxxxxxx>
> ---
>  drivers/dma/dw-edma/dw-hdma-v0-core.c | 4 ++--
>  drivers/dma/dw-edma/dw-hdma-v0-regs.h | 3 +--
>  include/linux/dma/edma.h              | 1 +
>  3 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> index 1f4cb7d..819ef1f 100644
> --- a/drivers/dma/dw-edma/dw-hdma-v0-core.c
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> @@ -54,7 +54,7 @@ static void dw_hdma_v0_core_off(struct dw_edma *dw)
>  {
>  	int id;
>  
> -	for (id = 0; id < HDMA_V0_MAX_NR_CH; id++) {
> +	for (id = 0; id < HDMA_MAX_NR_CH; id++) {
>  		SET_BOTH_CH_32(dw, id, int_setup,
>  			       HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
>  		SET_BOTH_CH_32(dw, id, int_clear,
> @@ -70,7 +70,7 @@ static u16 dw_hdma_v0_core_ch_count(struct dw_edma *dw, enum dw_edma_dir dir)
>  	 * available, we set it to maximum channels and let the platform
>  	 * set the right number of channels.
>  	 */
> -	return HDMA_V0_MAX_NR_CH;
> +	return HDMA_MAX_NR_CH;
>  }
>  
>  static enum dma_status dw_hdma_v0_core_ch_status(struct dw_edma_chan *chan)
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-regs.h b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> index a974abd..cd7eab2 100644
> --- a/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> @@ -11,7 +11,6 @@
>  
>  #include <linux/dmaengine.h>
>  
> -#define HDMA_V0_MAX_NR_CH			8
>  #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
>  #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)
>  #define HDMA_V0_LOCAL_STOP_INT_EN		BIT(4)
> @@ -92,7 +91,7 @@ struct dw_hdma_v0_ch {
>  } __packed;
>  
>  struct dw_hdma_v0_regs {
> -	struct dw_hdma_v0_ch ch[HDMA_V0_MAX_NR_CH];	/* 0x0000..0x0fa8 */
> +	struct dw_hdma_v0_ch ch[HDMA_MAX_NR_CH];	/* 0x0000..0x0fa8 */
>  } __packed;
>  
>  struct dw_hdma_v0_lli {
> diff --git a/include/linux/dma/edma.h b/include/linux/dma/edma.h
> index 550f6a4..2cdf249a 100644
> --- a/include/linux/dma/edma.h
> +++ b/include/linux/dma/edma.h
> @@ -14,6 +14,7 @@
>  
>  #define EDMA_MAX_WR_CH                                  8
>  #define EDMA_MAX_RD_CH                                  8
> +#define HDMA_MAX_NR_CH					8
>  
>  struct dw_edma;
>  struct dw_edma_chip;
> -- 
> 2.7.4
>