[PATCH v6 06/10] dmaengine: tegra: Support address width > 39 bits

Akhil R posted 10 patches 23 hours ago
[PATCH v6 06/10] dmaengine: tegra: Support address width > 39 bits
Posted by Akhil R 23 hours ago
Tegra264 supports address width of 41 bits. Unlike older SoCs which use
a common high_addr register for upper address bits, Tegra264 has separate
src_high and dst_high registers to accommodate this wider address space.

Add an addr_bits property to the device data structure to specify the
number of address bits supported on each device and use that to program
the appropriate registers.

Update the sg_req struct to remove the high_addr field and use
dma_addr_t for src and dst to store the complete addresses. Extract
the high address bits only when programming the registers.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/tegra186-gpc-dma.c | 83 +++++++++++++++++++++-------------
 1 file changed, 52 insertions(+), 31 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index b213c4ae07d2..3ac43ad19ed6 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -146,6 +146,7 @@ struct tegra_dma_channel;
  */
 struct tegra_dma_chip_data {
 	bool hw_support_pause;
+	unsigned int addr_bits;
 	unsigned int nr_channels;
 	unsigned int channel_reg_size;
 	unsigned int max_dma_count;
@@ -161,6 +162,8 @@ struct tegra_dma_channel_regs {
 	u32 src;
 	u32 dst;
 	u32 high_addr;
+	u32 src_high;
+	u32 dst_high;
 	u32 mc_seq;
 	u32 mmio_seq;
 	u32 wcount;
@@ -179,10 +182,9 @@ struct tegra_dma_channel_regs {
  */
 struct tegra_dma_sg_req {
 	unsigned int len;
+	dma_addr_t src;
+	dma_addr_t dst;
 	u32 csr;
-	u32 src;
-	u32 dst;
-	u32 high_addr;
 	u32 mc_seq;
 	u32 mmio_seq;
 	u32 wcount;
@@ -266,6 +268,25 @@ static inline struct device *tdc2dev(struct tegra_dma_channel *tdc)
 	return tdc->vc.chan.device->dev;
 }
 
+static void tegra_dma_program_addr(struct tegra_dma_channel *tdc,
+				   struct tegra_dma_sg_req *sg_req)
+{
+	tdc_write(tdc, tdc->regs->src, lower_32_bits(sg_req->src));
+	tdc_write(tdc, tdc->regs->dst, lower_32_bits(sg_req->dst));
+
+	if (tdc->tdma->chip_data->addr_bits > 39) {
+		tdc_write(tdc, tdc->regs->src_high, upper_32_bits(sg_req->src));
+		tdc_write(tdc, tdc->regs->dst_high, upper_32_bits(sg_req->dst));
+	} else {
+		u32 src_high = FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR,
+					      upper_32_bits(sg_req->src));
+		u32 dst_high = FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR,
+					      upper_32_bits(sg_req->dst));
+
+		tdc_write(tdc, tdc->regs->high_addr, src_high | dst_high);
+	}
+}
+
 static void tegra_dma_dump_chan_regs(struct tegra_dma_channel *tdc)
 {
 	dev_dbg(tdc2dev(tdc), "DMA Channel %d name %s register dump:\n",
@@ -274,10 +295,20 @@ static void tegra_dma_dump_chan_regs(struct tegra_dma_channel *tdc)
 		tdc_read(tdc, tdc->regs->csr),
 		tdc_read(tdc, tdc->regs->status),
 		tdc_read(tdc, tdc->regs->csre));
-	dev_dbg(tdc2dev(tdc), "SRC %x DST %x HI ADDR %x\n",
-		tdc_read(tdc, tdc->regs->src),
-		tdc_read(tdc, tdc->regs->dst),
-		tdc_read(tdc, tdc->regs->high_addr));
+
+	if (tdc->tdma->chip_data->addr_bits > 39) {
+		dev_dbg(tdc2dev(tdc), "SRC %x SRC HI %x DST %x DST HI %x\n",
+			tdc_read(tdc, tdc->regs->src),
+			tdc_read(tdc, tdc->regs->src_high),
+			tdc_read(tdc, tdc->regs->dst),
+			tdc_read(tdc, tdc->regs->dst_high));
+	} else {
+		dev_dbg(tdc2dev(tdc), "SRC %x DST %x HI ADDR %x\n",
+			tdc_read(tdc, tdc->regs->src),
+			tdc_read(tdc, tdc->regs->dst),
+			tdc_read(tdc, tdc->regs->high_addr));
+	}
+
 	dev_dbg(tdc2dev(tdc), "MCSEQ %x IOSEQ %x WCNT %x XFER %x WSTA %x\n",
 		tdc_read(tdc, tdc->regs->mc_seq),
 		tdc_read(tdc, tdc->regs->mmio_seq),
@@ -480,9 +511,7 @@ static void tegra_dma_configure_next_sg(struct tegra_dma_channel *tdc)
 	sg_req = &dma_desc->sg_req[dma_desc->sg_idx];
 
 	tdc_write(tdc, tdc->regs->wcount, sg_req->wcount);
-	tdc_write(tdc, tdc->regs->src, sg_req->src);
-	tdc_write(tdc, tdc->regs->dst, sg_req->dst);
-	tdc_write(tdc, tdc->regs->high_addr, sg_req->high_addr);
+	tegra_dma_program_addr(tdc, sg_req);
 
 	/* Start DMA */
 	tdc_write(tdc, tdc->regs->csr,
@@ -510,11 +539,9 @@ static void tegra_dma_start(struct tegra_dma_channel *tdc)
 
 	sg_req = &dma_desc->sg_req[dma_desc->sg_idx];
 
+	tegra_dma_program_addr(tdc, sg_req);
 	tdc_write(tdc, tdc->regs->wcount, sg_req->wcount);
 	tdc_write(tdc, tdc->regs->csr, 0);
-	tdc_write(tdc, tdc->regs->src, sg_req->src);
-	tdc_write(tdc, tdc->regs->dst, sg_req->dst);
-	tdc_write(tdc, tdc->regs->high_addr, sg_req->high_addr);
 	tdc_write(tdc, tdc->regs->fixed_pattern, sg_req->fixed_pattern);
 	tdc_write(tdc, tdc->regs->mmio_seq, sg_req->mmio_seq);
 	tdc_write(tdc, tdc->regs->mc_seq, sg_req->mc_seq);
@@ -819,7 +846,7 @@ static unsigned int get_burst_size(struct tegra_dma_channel *tdc,
 
 static int get_transfer_param(struct tegra_dma_channel *tdc,
 			      enum dma_transfer_direction direction,
-			      u32 *apb_addr,
+			      dma_addr_t *apb_addr,
 			      u32 *mmio_seq,
 			      u32 *csr,
 			      unsigned int *burst_size,
@@ -897,11 +924,9 @@ tegra_dma_prep_dma_memset(struct dma_chan *dc, dma_addr_t dest, int value,
 	dma_desc->bytes_req = len;
 	dma_desc->sg_count = 1;
 	sg_req = dma_desc->sg_req;
-
 	sg_req[0].src = 0;
 	sg_req[0].dst = dest;
-	sg_req[0].high_addr =
-			FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32));
+
 	sg_req[0].fixed_pattern = value;
 	/* Word count reg takes value as (N +1) words */
 	sg_req[0].wcount = ((len - 4) >> 2);
@@ -969,10 +994,7 @@ tegra_dma_prep_dma_memcpy(struct dma_chan *dc, dma_addr_t dest,
 
 	sg_req[0].src = src;
 	sg_req[0].dst = dest;
-	sg_req[0].high_addr =
-		FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (src >> 32));
-	sg_req[0].high_addr |=
-		FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (dest >> 32));
+
 	/* Word count reg takes value as (N +1) words */
 	sg_req[0].wcount = ((len - 4) >> 2);
 	sg_req[0].csr = csr;
@@ -992,7 +1014,8 @@ tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 	unsigned int max_dma_count = tdc->tdma->chip_data->max_dma_count;
 	enum dma_slave_buswidth slave_bw = DMA_SLAVE_BUSWIDTH_UNDEFINED;
-	u32 csr, mc_seq, apb_ptr = 0, mmio_seq = 0;
+	u32 csr, mc_seq, mmio_seq = 0;
+	dma_addr_t apb_ptr = 0;
 	struct tegra_dma_sg_req *sg_req;
 	struct tegra_dma_desc *dma_desc;
 	struct scatterlist *sg;
@@ -1080,13 +1103,9 @@ tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
 		if (direction == DMA_MEM_TO_DEV) {
 			sg_req[i].src = mem;
 			sg_req[i].dst = apb_ptr;
-			sg_req[i].high_addr =
-				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32));
 		} else if (direction == DMA_DEV_TO_MEM) {
 			sg_req[i].src = apb_ptr;
 			sg_req[i].dst = mem;
-			sg_req[i].high_addr =
-				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32));
 		}
 
 		/*
@@ -1110,7 +1129,8 @@ tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_l
 			  unsigned long flags)
 {
 	enum dma_slave_buswidth slave_bw = DMA_SLAVE_BUSWIDTH_UNDEFINED;
-	u32 csr, mc_seq, apb_ptr = 0, mmio_seq = 0, burst_size;
+	u32 csr, mc_seq, mmio_seq = 0, burst_size;
+	dma_addr_t apb_ptr = 0;
 	unsigned int max_dma_count, len, period_count, i;
 	struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc);
 	struct tegra_dma_desc *dma_desc;
@@ -1201,13 +1221,9 @@ tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_l
 		if (direction == DMA_MEM_TO_DEV) {
 			sg_req[i].src = mem;
 			sg_req[i].dst = apb_ptr;
-			sg_req[i].high_addr =
-				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR, (mem >> 32));
 		} else if (direction == DMA_DEV_TO_MEM) {
 			sg_req[i].src = apb_ptr;
 			sg_req[i].dst = mem;
-			sg_req[i].high_addr =
-				FIELD_PREP(TEGRA_GPCDMA_HIGH_ADDR_DST_PTR, (mem >> 32));
 		}
 		/*
 		 * Word count register takes input in words. Writing a value
@@ -1304,6 +1320,7 @@ static const struct tegra_dma_channel_regs tegra186_reg_offsets = {
 
 static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
 	.nr_channels = 32,
+	.addr_bits = 39,
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = false,
@@ -1313,6 +1330,7 @@ static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
 
 static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
 	.nr_channels = 32,
+	.addr_bits = 39,
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = true,
@@ -1322,6 +1340,7 @@ static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
 
 static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
 	.nr_channels = 32,
+	.addr_bits = 39,
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = true,
@@ -1433,6 +1452,8 @@ static int tegra_dma_probe(struct platform_device *pdev)
 		tdc->stream_id = stream_id;
 	}
 
+	dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(cdata->addr_bits));
+
 	dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask);
 	dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask);
 	dma_cap_set(DMA_MEMCPY, tdma->dma_dev.cap_mask);
-- 
2.50.1