]> git.ipfire.org Git - thirdparty/kernel/linux.git/commitdiff
dmaengine: tegra: Support address width > 39 bits
authorAkhil R <akhilrajeev@nvidia.com>
Tue, 31 Mar 2026 10:22:59 +0000 (15:52 +0530)
committerVinod Koul <vkoul@kernel.org>
Thu, 4 Jun 2026 06:51:19 +0000 (12:21 +0530)
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>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Link: https://patch.msgid.link/20260331102303.33181-7-akhilrajeev@nvidia.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
drivers/dma/tegra186-gpc-dma.c

index b213c4ae07d2a5ff694974f465d77b74b21def82..3ac43ad19ed60f287497fe582ca45d3ebe23165c 100644 (file)
@@ -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);