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From: "Verma, Devendra" <devverma@amd.com>
To: Devendra K Verma <devendra.verma@amd.com>,
	bhelgaas@google.com, mani@kernel.org, vkoul@kernel.org,
	Frank.Li@kernel.org
Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
	michal.simek@amd.com
Subject: Re: [PATCH RESEND v4] dmaengine: dw-edma: Enable HDMA 64R/W Channels
Date: Tue, 23 Jun 2026 16:58:51 +0530	[thread overview]
Message-ID: <095b8734-d599-46eb-be59-98107e73404f@amd.com> (raw)
In-Reply-To: <20260623112308.3377168-1-devendra.verma@amd.com>

Please ignore this resend. Details related to version change
got missed.

regards,
Devendra

On 23-Jun-26 16:53, Devendra K Verma wrote:
> As per 'Designware Cores PCI Express Controller Databook',
> Section 7.1 - Overview, HDMA supports 64 Read and 64 Write
> channels. Current controller driver supports up to 8 read and
> write channels only. In order to utilize all the channels the
> controller driver need to have the channel related structs
> and variables as per the number of channels supported by IP.
> Following changes are made to enable 64 Read / 64 Write
> channel support:
> 
>   o Defined HDMA specific macros to reflect the channel count.
>   o The count of ll_regions and dt_regions in dw_edma_chip and
>     dw_edma_pcie_data shall be in accordance to number of read
>     and write channels.
>   o In dw_edma_probe() configure the channels as per the channels
>     of the IP used.
>   o Changed mask types to u64 for higher channel counts.
> 
> Signed-off-by: Devendra K Verma <devendra.verma@amd.com>
> ---
>   drivers/dma/dw-edma/dw-edma-core.c    | 19 ++++++++++-----
>   drivers/dma/dw-edma/dw-edma-core.h    |  4 ++--
>   drivers/dma/dw-edma/dw-edma-pcie.c    |  8 +++----
>   drivers/dma/dw-edma/dw-hdma-v0-core.c | 33 ++++++++++++++++++++-------
>   drivers/dma/dw-edma/dw-hdma-v0-regs.h |  2 +-
>   include/linux/dma/edma.h              | 10 ++++----
>   6 files changed, 51 insertions(+), 25 deletions(-)
> 
> diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c
> index c2feb3adc79f..adf1b3939f96 100644
> --- a/drivers/dma/dw-edma/dw-edma-core.c
> +++ b/drivers/dma/dw-edma/dw-edma-core.c
> @@ -925,9 +925,9 @@ static int dw_edma_channel_setup(struct dw_edma *dw, u32 wr_alloc, u32 rd_alloc)
>   		irq = &dw->irq[pos];
>   
>   		if (chan->dir == EDMA_DIR_WRITE)
> -			irq->wr_mask |= BIT(chan->id);
> +			irq->wr_mask |= BIT_ULL(chan->id);
>   		else
> -			irq->rd_mask |= BIT(chan->id);
> +			irq->rd_mask |= BIT_ULL(chan->id);
>   
>   		irq->dw = dw;
>   		memcpy(&chan->msi, &irq->msi, sizeof(chan->msi));
> @@ -1079,6 +1079,8 @@ int dw_edma_probe(struct dw_edma_chip *chip)
>   	struct dw_edma *dw;
>   	u32 wr_alloc = 0;
>   	u32 rd_alloc = 0;
> +	u16 max_wr_cnt;
> +	u16 max_rd_cnt;
>   	int i, err;
>   
>   	if (!chip)
> @@ -1094,20 +1096,25 @@ int dw_edma_probe(struct dw_edma_chip *chip)
>   
>   	dw->chip = chip;
>   
> -	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE)
> +	if (dw->chip->mf == EDMA_MF_HDMA_NATIVE) {
>   		dw_hdma_v0_core_register(dw);
> -	else
> +		max_wr_cnt = HDMA_MAX_WR_CH;
> +		max_rd_cnt = HDMA_MAX_RD_CH;
> +	} else {
>   		dw_edma_v0_core_register(dw);
> +		max_wr_cnt = EDMA_MAX_WR_CH;
> +		max_rd_cnt = EDMA_MAX_RD_CH;
> +	}
>   
>   	raw_spin_lock_init(&dw->lock);
>   
>   	dw->wr_ch_cnt = min_t(u16, chip->ll_wr_cnt,
>   			      dw_edma_core_ch_count(dw, EDMA_DIR_WRITE));
> -	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH);
> +	dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, max_wr_cnt);
>   
>   	dw->rd_ch_cnt = min_t(u16, chip->ll_rd_cnt,
>   			      dw_edma_core_ch_count(dw, EDMA_DIR_READ));
> -	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH);
> +	dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, max_rd_cnt);
>   
>   	if (!dw->wr_ch_cnt && !dw->rd_ch_cnt)
>   		return -EINVAL;
> diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h
> index 902574b1ba86..d12fefbf3952 100644
> --- a/drivers/dma/dw-edma/dw-edma-core.h
> +++ b/drivers/dma/dw-edma/dw-edma-core.h
> @@ -91,8 +91,8 @@ struct dw_edma_chan {
>   
>   struct dw_edma_irq {
>   	struct msi_msg                  msi;
> -	u32				wr_mask;
> -	u32				rd_mask;
> +	u64				wr_mask;
> +	u64				rd_mask;
>   	struct dw_edma			*dw;
>   };
>   
> diff --git a/drivers/dma/dw-edma/dw-edma-pcie.c b/drivers/dma/dw-edma/dw-edma-pcie.c
> index 0b30ce138503..79f653da8e0f 100644
> --- a/drivers/dma/dw-edma/dw-edma-pcie.c
> +++ b/drivers/dma/dw-edma/dw-edma-pcie.c
> @@ -61,11 +61,11 @@ struct dw_edma_pcie_data {
>   	/* eDMA registers location */
>   	struct dw_edma_block		rg;
>   	/* eDMA memory linked list location */
> -	struct dw_edma_block		ll_wr[EDMA_MAX_WR_CH];
> -	struct dw_edma_block		ll_rd[EDMA_MAX_RD_CH];
> +	struct dw_edma_block		ll_wr[HDMA_MAX_WR_CH];
> +	struct dw_edma_block		ll_rd[HDMA_MAX_RD_CH];
>   	/* eDMA memory data location */
> -	struct dw_edma_block		dt_wr[EDMA_MAX_WR_CH];
> -	struct dw_edma_block		dt_rd[EDMA_MAX_RD_CH];
> +	struct dw_edma_block		dt_wr[HDMA_MAX_WR_CH];
> +	struct dw_edma_block		dt_rd[HDMA_MAX_RD_CH];
>   	/* Other */
>   	enum dw_edma_map_format		mf;
>   	u8				irqs;
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-core.c b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> index 632abb8b481c..84b0076f78bf 100644
> --- a/drivers/dma/dw-edma/dw-hdma-v0-core.c
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-core.c
> @@ -53,13 +53,24 @@ __dw_ch_regs(struct dw_edma *dw, enum dw_edma_dir dir, u16 ch)
>   static void dw_hdma_v0_core_off(struct dw_edma *dw)
>   {
>   	int id;
> +	enum dw_edma_dir dir;
> +
> +	dir = EDMA_DIR_WRITE;
> +	for (id = 0; id < dw->wr_ch_cnt; id++) {
> +		SET_CH_32(dw, dir, id, int_setup,
> +			  HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> +		SET_CH_32(dw, dir, id, int_clear,
> +			  HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> +		SET_CH_32(dw, dir, id, ch_en, 0);
> +	}
>   
> -	for (id = 0; id < HDMA_V0_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,
> -			       HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> -		SET_BOTH_CH_32(dw, id, ch_en, 0);
> +	dir = EDMA_DIR_READ;
> +	for (id = 0; id < dw->rd_ch_cnt; id++) {
> +		SET_CH_32(dw, dir, id, int_setup,
> +			  HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> +		SET_CH_32(dw, dir, id, int_clear,
> +			  HDMA_V0_STOP_INT_MASK | HDMA_V0_ABORT_INT_MASK);
> +		SET_CH_32(dw, dir, id, ch_en, 0);
>   	}
>   }
>   
> @@ -118,7 +129,8 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
>   	unsigned long total, pos, val;
>   	irqreturn_t ret = IRQ_NONE;
>   	struct dw_edma_chan *chan;
> -	unsigned long off, mask;
> +	unsigned long off;
> +	u64 mask;
>   
>   	if (dir == EDMA_DIR_WRITE) {
>   		total = dw->wr_ch_cnt;
> @@ -130,7 +142,11 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
>   		mask = dw_irq->rd_mask;
>   	}
>   
> -	for_each_set_bit(pos, &mask, total) {
> +	while (mask) {
> +		pos = __ffs64(mask);
> +		if (pos >= total)
> +			break;
> +
>   		chan = &dw->chan[pos + off];
>   
>   		val = dw_hdma_v0_core_status_int(chan);
> @@ -147,6 +163,7 @@ dw_hdma_v0_core_handle_int(struct dw_edma_irq *dw_irq, enum dw_edma_dir dir,
>   
>   			ret = IRQ_HANDLED;
>   		}
> +		mask &= mask - 1;
>   	}
>   
>   	return ret;
> diff --git a/drivers/dma/dw-edma/dw-hdma-v0-regs.h b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> index 7759ba9b4850..48e40efceb2e 100644
> --- a/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> +++ b/drivers/dma/dw-edma/dw-hdma-v0-regs.h
> @@ -11,7 +11,7 @@
>   
>   #include <linux/dmaengine.h>
>   
> -#define HDMA_V0_MAX_NR_CH			8
> +#define HDMA_V0_MAX_NR_CH			64
>   #define HDMA_V0_CH_EN				BIT(0)
>   #define HDMA_V0_LOCAL_ABORT_INT_EN		BIT(6)
>   #define HDMA_V0_REMOTE_ABORT_INT_EN		BIT(5)
> diff --git a/include/linux/dma/edma.h b/include/linux/dma/edma.h
> index 1fafd5b0e315..da7a5cc93ad4 100644
> --- a/include/linux/dma/edma.h
> +++ b/include/linux/dma/edma.h
> @@ -14,6 +14,8 @@
>   
>   #define EDMA_MAX_WR_CH                                  8
>   #define EDMA_MAX_RD_CH                                  8
> +#define HDMA_MAX_WR_CH                                  64
> +#define HDMA_MAX_RD_CH                                  64
>   
>   struct dw_edma;
>   
> @@ -89,12 +91,12 @@ struct dw_edma_chip {
>   	u16			ll_wr_cnt;
>   	u16			ll_rd_cnt;
>   	/* link list address */
> -	struct dw_edma_region	ll_region_wr[EDMA_MAX_WR_CH];
> -	struct dw_edma_region	ll_region_rd[EDMA_MAX_RD_CH];
> +	struct dw_edma_region	ll_region_wr[HDMA_MAX_WR_CH];
> +	struct dw_edma_region	ll_region_rd[HDMA_MAX_RD_CH];
>   
>   	/* data region */
> -	struct dw_edma_region	dt_region_wr[EDMA_MAX_WR_CH];
> -	struct dw_edma_region	dt_region_rd[EDMA_MAX_RD_CH];
> +	struct dw_edma_region	dt_region_wr[HDMA_MAX_WR_CH];
> +	struct dw_edma_region	dt_region_rd[HDMA_MAX_RD_CH];
>   
>   	/* interrupt emulation */
>   	int			db_irq;


  reply	other threads:[~2026-06-23 11:29 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-23 11:23 [PATCH RESEND v4] dmaengine: dw-edma: Enable HDMA 64R/W Channels Devendra K Verma
2026-06-23 11:28 ` Verma, Devendra [this message]
2026-06-23 11:39 ` sashiko-bot
  -- strict thread matches above, loose matches on Subject: below --
2026-06-23 11:26 Devendra K Verma
2026-06-23 11:41 ` sashiko-bot

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