Commit c4994a98 authored by Li Yu's avatar Li Yu Committed by Vinod Koul
Browse files

dmaengine: k3dma: Add support for dma-channel-mask 



Add dma-channel-mask as a property for k3dma, it defines
available dma channels which a non-secure mode driver can use.

One sample usage of this is in Hi3660 SoC. DMA channel 0 is
reserved to lpm3, which is a coprocessor for power management. So
as a result, any request in kernel (which runs on main processor
and in non-secure mode) should start from at least channel 1.

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Tanglei Han <hantanglei@huawei.com>
Cc: Zhuangluan Su <suzhuangluan@hisilicon.com>
Cc: Ryan Grachek <ryan@edited.us>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Guodong Xu <guodong.xu@linaro.org>
Cc: dmaengine@vger.kernel.org
Signed-off-by: default avatarLi Yu <liyu65@hisilicon.com>
[jstultz: Reworked to use a channel mask]
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 1200e070

drivers/dma/k3dma.c

+19 −1
Original line number Diff line number Diff line
@@ -111,6 +111,7 @@ struct k3_dma_dev { 
	struct dma_pool		*pool;

	u32			dma_channels;

	u32			dma_requests;

	u32			dma_channel_mask;

	unsigned int		irq;

};
@@ -319,6 +320,9 @@ static void k3_dma_tasklet(unsigned long arg) 
	/* check new channel request in d->chan_pending */

	spin_lock_irq(&d->lock);

	for (pch = 0; pch < d->dma_channels; pch++) {

		if (!(d->dma_channel_mask & (1 << pch)))

			continue;



		p = &d->phy[pch];



		if (p->vchan == NULL && !list_empty(&d->chan_pending)) {
@@ -336,6 +340,9 @@ static void k3_dma_tasklet(unsigned long arg) 
	spin_unlock_irq(&d->lock);



	for (pch = 0; pch < d->dma_channels; pch++) {

		if (!(d->dma_channel_mask & (1 << pch)))

			continue;



		if (pch_alloc & (1 << pch)) {

			p = &d->phy[pch];

			c = p->vchan;
@@ -856,6 +863,13 @@ static int k3_dma_probe(struct platform_device *op) 
				"dma-channels", &d->dma_channels);

		of_property_read_u32((&op->dev)->of_node,

				"dma-requests", &d->dma_requests);

		ret = of_property_read_u32((&op->dev)->of_node,

				"dma-channel-mask", &d->dma_channel_mask);

		if (ret) {

			dev_warn(&op->dev,

				 "dma-channel-mask doesn't exist, considering all as available.\n");

			d->dma_channel_mask = (u32)~0UL;

		}

	}



	if (!(soc_data->flags & K3_FLAG_NOCLK)) {
@@ -887,8 +901,12 @@ static int k3_dma_probe(struct platform_device *op) 
		return -ENOMEM;



	for (i = 0; i < d->dma_channels; i++) {

		struct k3_dma_phy *p = &d->phy[i];

		struct k3_dma_phy *p;



		if (!(d->dma_channel_mask & BIT(i)))

			continue;



		p = &d->phy[i];

		p->idx = i;

		p->base = d->base + i * 0x40;

	}

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