dmaengine: ti: edma: Add support for handling reserved channels (31f4b28f) · Commits · 戴 / test

drivers/dma/ti/edma.c

+53 −6

Original line number	Diff line number	Diff line
		@@ -260,6 +260,13 @@ struct edma_cc {
		*/
		unsigned long *slot_inuse;

		/*
		* For tracking reserved channels used by DSP.
		* If the bit is cleared, the channel is allocated to be used by DSP
		* and Linux must not touch it.
		*/
		unsigned long *channels_mask;

		struct dma_device dma_slave;
		struct dma_device *dma_memcpy;
		struct edma_chan *slave_chans;
		@@ -716,6 +723,12 @@ static int edma_alloc_channel(struct edma_chan *echan,
		struct edma_cc *ecc = echan->ecc;
		int channel = EDMA_CHAN_SLOT(echan->ch_num);

		if (!test_bit(echan->ch_num, ecc->channels_mask)) {
		dev_err(ecc->dev, "Channel%d is reserved, can not be used!\n",
		echan->ch_num);
		return -EINVAL;
		}

		/* ensure access through shadow region 0 */
		edma_or_array2(ecc, EDMA_DRAE, 0, EDMA_REG_ARRAY_INDEX(channel),
		EDMA_CHANNEL_BIT(channel));
		@@ -2249,7 +2262,7 @@ static int edma_probe(struct platform_device *pdev)
		{
		struct edma_soc_info *info = pdev->dev.platform_data;
		s8 (*queue_priority_mapping)[2];
		const s16 (*rsv_slots)[2];
		const s16 (*reserved)[2];
		int i, irq;
		char *irq_name;
		struct resource *mem;
		@@ -2329,15 +2342,32 @@ static int edma_probe(struct platform_device *pdev)
		if (!ecc->slot_inuse)
		return -ENOMEM;

		ecc->channels_mask = devm_kcalloc(dev,
		BITS_TO_LONGS(ecc->num_channels),
		sizeof(unsigned long), GFP_KERNEL);
		if (!ecc->channels_mask)
		return -ENOMEM;

		/* Mark all channels available initially */
		bitmap_fill(ecc->channels_mask, ecc->num_channels);

		ecc->default_queue = info->default_queue;

		if (info->rsv) {
		/* Set the reserved slots in inuse list */
		rsv_slots = info->rsv->rsv_slots;
		if (rsv_slots) {
		for (i = 0; rsv_slots[i][0] != -1; i++)
		bitmap_set(ecc->slot_inuse, rsv_slots[i][0],
		rsv_slots[i][1]);
		reserved = info->rsv->rsv_slots;
		if (reserved) {
		for (i = 0; reserved[i][0] != -1; i++)
		bitmap_set(ecc->slot_inuse, reserved[i][0],
		reserved[i][1]);
		}

		/* Clear channels not usable for Linux */
		reserved = info->rsv->rsv_chans;
		if (reserved) {
		for (i = 0; reserved[i][0] != -1; i++)
		bitmap_clear(ecc->channels_mask, reserved[i][0],
		reserved[i][1]);
		}
		}

		@@ -2389,6 +2419,7 @@ static int edma_probe(struct platform_device *pdev)

		if (!ecc->legacy_mode) {
		int lowest_priority = 0;
		unsigned int array_max;
		struct of_phandle_args tc_args;

		ecc->tc_list = devm_kcalloc(dev, ecc->num_tc,
		@@ -2410,6 +2441,18 @@ static int edma_probe(struct platform_device *pdev)
		info->default_queue = i;
		}
		}

		/* See if we have optional dma-channel-mask array */
		array_max = DIV_ROUND_UP(ecc->num_channels, BITS_PER_TYPE(u32));
		ret = of_property_read_variable_u32_array(node,
		"dma-channel-mask",
		(u32 *)ecc->channels_mask,
		1, array_max);
		if (ret > 0 && ret != array_max)
		dev_warn(dev, "dma-channel-mask is not complete.\n");
		else if (ret == -EOVERFLOW \|\| ret == -ENODATA)
		dev_warn(dev,
		"dma-channel-mask is out of range or empty\n");
		}

		/* Event queue priority mapping */
		@@ -2427,6 +2470,10 @@ static int edma_probe(struct platform_device *pdev)
		edma_dma_init(ecc, legacy_mode);

		for (i = 0; i < ecc->num_channels; i++) {
		/* Do not touch reserved channels */
		if (!test_bit(i, ecc->channels_mask))
		continue;

		/* Assign all channels to the default queue */
		edma_assign_channel_eventq(&ecc->slave_chans[i],
		info->default_queue);

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