Commit 09b3c323 authored by Russell King - ARM Linux's avatar Russell King - ARM Linux Committed by Dan Williams
Browse files

ARM: PL08x: assign ccfg DMA request signal in prep_phy_channel() 



There is no need to wait until we start processing a tx descriptor
before setting up the DMA request selection in the ccfg register.
We know which channel and request will be used in prep_phy_channel(),
so setup the ccfg request selection at txd creation time in
prep_phy_channel().

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Acked-by: default avatarLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 4983a04f

drivers/dma/amba-pl08x.c

+9 −11
Original line number Diff line number Diff line
@@ -194,18 +194,10 @@ static void pl08x_start_txd(struct pl08x_dma_chan *plchan, 
	struct pl08x_driver_data *pl08x = plchan->host;

	struct pl08x_phy_chan *phychan = plchan->phychan;

	struct pl08x_lli *lli = &txd->llis_va[0];

	u32 val, ccfg = txd->ccfg;

	u32 val;



	plchan->at = txd;



	/* Assign the flow control signal to this channel */

	if (txd->direction == DMA_TO_DEVICE)

		/* Select signal as destination */

		ccfg |= phychan->signal << PL080_CONFIG_DST_SEL_SHIFT;

	else if (txd->direction == DMA_FROM_DEVICE)

		/* Select signal as source */

		ccfg |= phychan->signal << PL080_CONFIG_SRC_SEL_SHIFT;



	/* Wait for channel inactive */

	while (pl08x_phy_channel_busy(phychan))

		cpu_relax();
@@ -214,13 +206,13 @@ static void pl08x_start_txd(struct pl08x_dma_chan *plchan, 
		"WRITE channel %d: csrc=0x%08x, cdst=0x%08x, "

		"clli=0x%08x, cctl=0x%08x, ccfg=0x%08x\n",

		phychan->id, lli->src, lli->dst, lli->lli, lli->cctl,

		ccfg);

		txd->ccfg);



	writel(lli->src, phychan->base + PL080_CH_SRC_ADDR);

	writel(lli->dst, phychan->base + PL080_CH_DST_ADDR);

	writel(lli->lli, phychan->base + PL080_CH_LLI);

	writel(lli->cctl, phychan->base + PL080_CH_CONTROL);

	writel(ccfg, phychan->base + PL080_CH_CONFIG);

	writel(txd->ccfg, phychan->base + PL080_CH_CONFIG);



	/* Enable the DMA channel */

	/* Do not access config register until channel shows as disabled */
@@ -1001,6 +993,12 @@ static int prep_phy_channel(struct pl08x_dma_chan *plchan, 
			return -EBUSY;

		}

		ch->signal = ret;



		/* Assign the flow control signal to this channel */

		if (txd->direction == DMA_TO_DEVICE)

			txd->ccfg |= ch->signal << PL080_CONFIG_DST_SEL_SHIFT;

		else if (txd->direction == DMA_FROM_DEVICE)

			txd->ccfg |= ch->signal << PL080_CONFIG_SRC_SEL_SHIFT;

	}



	dev_dbg(&pl08x->adev->dev, "allocated physical channel %d and signal %d for xfer on %s\n",

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