[PATCH v5 00/10] Add GPCDMA support in Tegra264

[PATCH v5 00/10] Add GPCDMA support in Tegra264

[Akhil R]

This series adds support for GPCDMA in Tegra264 with additional
support for separate stream ID for each channel. Tegra264 GPCDMA
controller has changes in the register offsets and uses 41-bit
addressing for memory. Add changes in the tegra186-gpc-dma driver
to support these.

v4->v5:
- Use dev_err_probe() when returning error from the probe function.
- Remove tegra194 and tegra234 compatible from the reset 'if' condition
  in the bindings as suggested in v2 (which I missed).
v3->v4:
- Split device tree changes to two patches.
- Reordered patches to have fixes first.
- Added fixes tag to dt-bindings and device tree changes.
v2->v3:
- Add description for iommu-map property and update commit descriptions.
- Use enum for compatible string instead of const.
- Remove unused registers from struct tegra_dma_channel_regs.
- Use devm_of_dma_controller_register() to register the DMA controller.
- Remove return value check for mask setting in the driver as the bitmask
  value is always greater than 32.
v1->v2:
- Fix dt_bindings_check warnings
- Drop fallback compatible "nvidia,tegra186-gpcdma" from Tegra264 DT
- Use dma_addr_t for sg_req src/dst fields and drop separate high_add
  variable and check for the addr_bits only when programming the
  registers.
- Update address width to 39 bits for Tegra234 and before since the SMMU
  supports only up to 39 bits till Tegra234.
- Add a patch to do managed DMA controller registration.
- Describe the second iteration in the probe.
- Update commit descriptions.

Akhil R (10):
  dt-bindings: dma: nvidia,tegra186-gpc-dma: Make reset optional
  arm64: tegra: Remove fallback compatible for GPCDMA
  dt-bindings: dma: nvidia,tegra186-gpc-dma: Add iommu-map property
  dmaengine: tegra: Make reset control optional
  dmaengine: tegra: Use struct for register offsets
  dmaengine: tegra: Support address width > 39 bits
  dmaengine: tegra: Use managed DMA controller registration
  dmaengine: tegra: Use iommu-map for stream ID
  dmaengine: tegra: Add Tegra264 support
  arm64: tegra: Enable GPCDMA in Tegra264 and add iommu-map

 .../bindings/dma/nvidia,tegra186-gpc-dma.yaml |  32 +-
 .../arm64/boot/dts/nvidia/tegra264-p3834.dtsi |   4 +
 arch/arm64/boot/dts/nvidia/tegra264.dtsi      |   3 +-
 drivers/dma/tegra186-gpc-dma.c                | 433 +++++++++++-------
 4 files changed, 288 insertions(+), 184 deletions(-)

-- 
2.50.1

[PATCH v5 01/10] dt-bindings: dma: nvidia,tegra186-gpc-dma: Make reset optional

[Akhil R]

On Tegra264, GPCDMA reset control is not exposed to Linux and is handled
by the boot firmware.

Although reset was not exposed in Tegra234 as well, the firmware supported
a dummy reset which just returns success on reset without doing an actual
reset. This is also not supported in Tegra264 BPMP. Therefore mark 'reset'
and 'reset-names' properties as required only for devices prior to
Tegra264.

This also necessitates that the Tegra264 compatible be standalone and
cannot have the fallback compatible of Tegra186. Since there is no
functional impact, we keep reset as required for Tegra234 to avoid
breaking the ABI.

Fixes: bb8c97571db5 ("dt-bindings: dma: Add Tegra264 compatible string")
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
---
 .../bindings/dma/nvidia,tegra186-gpc-dma.yaml | 23 +++++++++++++------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
index 0dabe9bbb219..64f1e9d9896d 100644
--- a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
@@ -15,16 +15,14 @@ maintainers:
   - Jon Hunter <jonathanh@nvidia.com>
   - Rajesh Gumasta <rgumasta@nvidia.com>
 
-allOf:
-  - $ref: dma-controller.yaml#
-
 properties:
   compatible:
     oneOf:
-      - const: nvidia,tegra186-gpcdma
+      - enum:
+          - nvidia,tegra264-gpcdma
+          - nvidia,tegra186-gpcdma
       - items:
           - enum:
-              - nvidia,tegra264-gpcdma
               - nvidia,tegra234-gpcdma
               - nvidia,tegra194-gpcdma
           - const: nvidia,tegra186-gpcdma
@@ -60,12 +58,23 @@ required:
   - compatible
   - reg
   - interrupts
-  - resets
-  - reset-names
   - "#dma-cells"
   - iommus
   - dma-channel-mask
 
+allOf:
+  - $ref: dma-controller.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - nvidia,tegra186-gpcdma
+    then:
+      required:
+        - resets
+        - reset-names
+
 additionalProperties: false
 
 examples:
-- 
2.50.1

[PATCH v5 02/10] arm64: tegra: Remove fallback compatible for GPCDMA

[Akhil R]

Remove the fallback compatible string "nvidia,tegra186-gpcdma" for GPCDMA
in Tegra264. Tegra186 compatible cannot work on Tegra264 because of the
register offset changes and absence of the reset property.

Fixes: 65ef237e4810 ("arm64: tegra: Add Tegra264 support")
Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra264.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra264.dtsi b/arch/arm64/boot/dts/nvidia/tegra264.dtsi
index 24cc2c51a272..af077420d7d9 100644
--- a/arch/arm64/boot/dts/nvidia/tegra264.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra264.dtsi
@@ -3208,7 +3208,7 @@ agic_page5: interrupt-controller@99b0000 {
 		};
 
 		gpcdma: dma-controller@8400000 {
-			compatible = "nvidia,tegra264-gpcdma", "nvidia,tegra186-gpcdma";
+			compatible = "nvidia,tegra264-gpcdma";
 			reg = <0x0 0x08400000 0x0 0x210000>;
 			interrupts = <GIC_SPI 584 IRQ_TYPE_LEVEL_HIGH>,
 				     <GIC_SPI 585 IRQ_TYPE_LEVEL_HIGH>,
-- 
2.50.1

[PATCH v5 03/10] dt-bindings: dma: nvidia,tegra186-gpc-dma: Add iommu-map property

[Akhil R]

Add iommu-map property to specify separate stream IDs for each DMA
channel. This enables each channel to be in its own IOMMU domain,
keeping memory isolated from other devices sharing the same DMA
controller.

Define the constraints such that if the channel and stream IDs are
contiguous, a single entry can map all the channels, but if the
channels or stream IDs are non-contiguous support multiple entries.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
---
 .../devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
index 64f1e9d9896d..bc093c783d98 100644
--- a/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
+++ b/Documentation/devicetree/bindings/dma/nvidia,tegra186-gpc-dma.yaml
@@ -14,6 +14,7 @@ description: |
 maintainers:
   - Jon Hunter <jonathanh@nvidia.com>
   - Rajesh Gumasta <rgumasta@nvidia.com>
+  - Akhil R <akhilrajeev@nvidia.com>
 
 properties:
   compatible:
@@ -49,6 +50,14 @@ properties:
   iommus:
     maxItems: 1
 
+  iommu-map:
+    description:
+      Maps DMA channel numbers to IOMMU stream IDs. A single entry can map all
+      channels when stream IDs are contiguous. In systems where the channels or
+      stream IDs are not contiguous, multiple entries may be needed.
+    minItems: 1
+    maxItems: 32
+
   dma-coherent: true
 
   dma-channel-mask:
-- 
2.50.1

[PATCH v5 04/10] dmaengine: tegra: Make reset control optional

[Akhil R]

On Tegra264, reset is not available for the driver to control as
this is handled by the boot firmware. Hence make the reset control
optional and update the error message to reflect the correct error.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/tegra186-gpc-dma.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index 5948fbf32c21..a0522a992ebc 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -1381,10 +1381,10 @@ static int tegra_dma_probe(struct platform_device *pdev)
 	if (IS_ERR(tdma->base_addr))
 		return PTR_ERR(tdma->base_addr);
 
-	tdma->rst = devm_reset_control_get_exclusive(&pdev->dev, "gpcdma");
+	tdma->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, "gpcdma");
 	if (IS_ERR(tdma->rst)) {
 		return dev_err_probe(&pdev->dev, PTR_ERR(tdma->rst),
-			      "Missing controller reset\n");
+			      "Failed to get controller reset\n");
 	}
 	reset_control_reset(tdma->rst);
 
-- 
2.50.1

[PATCH v5 05/10] dmaengine: tegra: Use struct for register offsets

[Akhil R]

Repurpose the struct tegra_dma_channel_regs to define offsets for all the
channel registers. Previously, the struct only held the register values
for each transfer and was wrapped within tegra_dma_sg_req. Move the
values directly into tegra_dma_sg_req and use channel_regs for
storing the register offsets. Update all register reads/writes to use
the struct channel_regs. This prepares for the register offset change
in Tegra264.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/tegra186-gpc-dma.c | 282 +++++++++++++++++----------------
 1 file changed, 142 insertions(+), 140 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index a0522a992ebc..b213c4ae07d2 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -22,7 +22,6 @@
 #include "virt-dma.h"
 
 /* CSR register */
-#define TEGRA_GPCDMA_CHAN_CSR			0x00
 #define TEGRA_GPCDMA_CSR_ENB			BIT(31)
 #define TEGRA_GPCDMA_CSR_IE_EOC			BIT(30)
 #define TEGRA_GPCDMA_CSR_ONCE			BIT(27)
@@ -58,7 +57,6 @@
 #define TEGRA_GPCDMA_CSR_WEIGHT			GENMASK(13, 10)
 
 /* STATUS register */
-#define TEGRA_GPCDMA_CHAN_STATUS		0x004
 #define TEGRA_GPCDMA_STATUS_BUSY		BIT(31)
 #define TEGRA_GPCDMA_STATUS_ISE_EOC		BIT(30)
 #define TEGRA_GPCDMA_STATUS_PING_PONG		BIT(28)
@@ -70,22 +68,13 @@
 #define TEGRA_GPCDMA_STATUS_IRQ_STA		BIT(21)
 #define TEGRA_GPCDMA_STATUS_IRQ_TRIG_STA	BIT(20)
 
-#define TEGRA_GPCDMA_CHAN_CSRE			0x008
 #define TEGRA_GPCDMA_CHAN_CSRE_PAUSE		BIT(31)
 
-/* Source address */
-#define TEGRA_GPCDMA_CHAN_SRC_PTR		0x00C
-
-/* Destination address */
-#define TEGRA_GPCDMA_CHAN_DST_PTR		0x010
-
 /* High address pointer */
-#define TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR		0x014
 #define TEGRA_GPCDMA_HIGH_ADDR_SRC_PTR		GENMASK(7, 0)
 #define TEGRA_GPCDMA_HIGH_ADDR_DST_PTR		GENMASK(23, 16)
 
 /* MC sequence register */
-#define TEGRA_GPCDMA_CHAN_MCSEQ			0x18
 #define TEGRA_GPCDMA_MCSEQ_DATA_SWAP		BIT(31)
 #define TEGRA_GPCDMA_MCSEQ_REQ_COUNT		GENMASK(30, 25)
 #define TEGRA_GPCDMA_MCSEQ_BURST		GENMASK(24, 23)
@@ -101,7 +90,6 @@
 #define TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK	GENMASK(6, 0)
 
 /* MMIO sequence register */
-#define TEGRA_GPCDMA_CHAN_MMIOSEQ			0x01c
 #define TEGRA_GPCDMA_MMIOSEQ_DBL_BUF		BIT(31)
 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH		GENMASK(30, 28)
 #define TEGRA_GPCDMA_MMIOSEQ_BUS_WIDTH_8	\
@@ -120,17 +108,7 @@
 #define TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD		GENMASK(18, 16)
 #define TEGRA_GPCDMA_MMIOSEQ_MMIO_PROT		GENMASK(8, 7)
 
-/* Channel WCOUNT */
-#define TEGRA_GPCDMA_CHAN_WCOUNT		0x20
-
-/* Transfer count */
-#define TEGRA_GPCDMA_CHAN_XFER_COUNT		0x24
-
-/* DMA byte count status */
-#define TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS	0x28
-
 /* Error Status Register */
-#define TEGRA_GPCDMA_CHAN_ERR_STATUS		0x30
 #define TEGRA_GPCDMA_CHAN_ERR_TYPE_SHIFT	8
 #define TEGRA_GPCDMA_CHAN_ERR_TYPE_MASK	0xF
 #define TEGRA_GPCDMA_CHAN_ERR_TYPE(err)	(			\
@@ -143,16 +121,6 @@
 #define TEGRA_DMA_MC_SLAVE_ERR			0xB
 #define TEGRA_DMA_MMIO_SLAVE_ERR		0xA
 
-/* Fixed Pattern */
-#define TEGRA_GPCDMA_CHAN_FIXED_PATTERN		0x34
-
-#define TEGRA_GPCDMA_CHAN_TZ			0x38
-#define TEGRA_GPCDMA_CHAN_TZ_MMIO_PROT_1	BIT(0)
-#define TEGRA_GPCDMA_CHAN_TZ_MC_PROT_1		BIT(1)
-
-#define TEGRA_GPCDMA_CHAN_SPARE			0x3c
-#define TEGRA_GPCDMA_CHAN_SPARE_EN_LEGACY_FC	BIT(16)
-
 /*
  * If any burst is in flight and DMA paused then this is the time to complete
  * on-flight burst and update DMA status register.
@@ -181,18 +149,24 @@ struct tegra_dma_chip_data {
 	unsigned int nr_channels;
 	unsigned int channel_reg_size;
 	unsigned int max_dma_count;
+	const struct tegra_dma_channel_regs *channel_regs;
 	int (*terminate)(struct tegra_dma_channel *tdc);
 };
 
 /* DMA channel registers */
 struct tegra_dma_channel_regs {
 	u32 csr;
-	u32 src_ptr;
-	u32 dst_ptr;
-	u32 high_addr_ptr;
+	u32 status;
+	u32 csre;
+	u32 src;
+	u32 dst;
+	u32 high_addr;
 	u32 mc_seq;
 	u32 mmio_seq;
 	u32 wcount;
+	u32 wxfer;
+	u32 wstatus;
+	u32 err_status;
 	u32 fixed_pattern;
 };
 
@@ -205,7 +179,14 @@ struct tegra_dma_channel_regs {
  */
 struct tegra_dma_sg_req {
 	unsigned int len;
-	struct tegra_dma_channel_regs ch_regs;
+	u32 csr;
+	u32 src;
+	u32 dst;
+	u32 high_addr;
+	u32 mc_seq;
+	u32 mmio_seq;
+	u32 wcount;
+	u32 fixed_pattern;
 };
 
 /*
@@ -228,19 +209,20 @@ struct tegra_dma_desc {
  * tegra_dma_channel: Channel specific information
  */
 struct tegra_dma_channel {
-	bool config_init;
-	char name[30];
-	enum dma_transfer_direction sid_dir;
-	enum dma_status status;
-	int id;
-	int irq;
-	int slave_id;
+	const struct tegra_dma_channel_regs *regs;
 	struct tegra_dma *tdma;
 	struct virt_dma_chan vc;
 	struct tegra_dma_desc *dma_desc;
 	struct dma_slave_config dma_sconfig;
+	enum dma_transfer_direction sid_dir;
+	enum dma_status status;
 	unsigned int stream_id;
 	unsigned long chan_base_offset;
+	bool config_init;
+	char name[30];
+	int id;
+	int irq;
+	int slave_id;
 };
 
 /*
@@ -288,22 +270,22 @@ static void tegra_dma_dump_chan_regs(struct tegra_dma_channel *tdc)
 {
 	dev_dbg(tdc2dev(tdc), "DMA Channel %d name %s register dump:\n",
 		tdc->id, tdc->name);
-	dev_dbg(tdc2dev(tdc), "CSR %x STA %x CSRE %x SRC %x DST %x\n",
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_DST_PTR)
-	);
-	dev_dbg(tdc2dev(tdc), "MCSEQ %x IOSEQ %x WCNT %x XFER %x BSTA %x\n",
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_WCOUNT),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT),
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_DMA_BYTE_STATUS)
-	);
+	dev_dbg(tdc2dev(tdc), "CSR %x STA %x CSRE %x\n",
+		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));
+	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),
+		tdc_read(tdc, tdc->regs->wcount),
+		tdc_read(tdc, tdc->regs->wxfer),
+		tdc_read(tdc, tdc->regs->wstatus));
 	dev_dbg(tdc2dev(tdc), "DMA ERR_STA %x\n",
-		tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS));
+		tdc_read(tdc, tdc->regs->err_status));
 }
 
 static int tegra_dma_sid_reserve(struct tegra_dma_channel *tdc,
@@ -377,13 +359,13 @@ static int tegra_dma_pause(struct tegra_dma_channel *tdc)
 	int ret;
 	u32 val;
 
-	val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE);
+	val = tdc_read(tdc, tdc->regs->csre);
 	val |= TEGRA_GPCDMA_CHAN_CSRE_PAUSE;
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, val);
+	tdc_write(tdc, tdc->regs->csre, val);
 
 	/* Wait until busy bit is de-asserted */
 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
-			tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS,
+			tdc->chan_base_offset + tdc->regs->status,
 			val,
 			!(val & TEGRA_GPCDMA_STATUS_BUSY),
 			TEGRA_GPCDMA_BURST_COMPLETE_TIME,
@@ -419,9 +401,9 @@ static void tegra_dma_resume(struct tegra_dma_channel *tdc)
 {
 	u32 val;
 
-	val = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSRE);
+	val = tdc_read(tdc, tdc->regs->csre);
 	val &= ~TEGRA_GPCDMA_CHAN_CSRE_PAUSE;
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSRE, val);
+	tdc_write(tdc, tdc->regs->csre, val);
 
 	tdc->status = DMA_IN_PROGRESS;
 }
@@ -456,27 +438,27 @@ static void tegra_dma_disable(struct tegra_dma_channel *tdc)
 {
 	u32 csr, status;
 
-	csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
+	csr = tdc_read(tdc, tdc->regs->csr);
 
 	/* Disable interrupts */
 	csr &= ~TEGRA_GPCDMA_CSR_IE_EOC;
 
 	/* Disable DMA */
 	csr &= ~TEGRA_GPCDMA_CSR_ENB;
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
+	tdc_write(tdc, tdc->regs->csr, csr);
 
 	/* Clear interrupt status if it is there */
-	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+	status = tdc_read(tdc, tdc->regs->status);
 	if (status & TEGRA_GPCDMA_STATUS_ISE_EOC) {
 		dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__);
-		tdc_write(tdc, TEGRA_GPCDMA_CHAN_STATUS, status);
+		tdc_write(tdc, tdc->regs->status, status);
 	}
 }
 
 static void tegra_dma_configure_next_sg(struct tegra_dma_channel *tdc)
 {
 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
-	struct tegra_dma_channel_regs *ch_regs;
+	struct tegra_dma_sg_req *sg_req;
 	int ret;
 	u32 val;
 
@@ -488,29 +470,29 @@ static void tegra_dma_configure_next_sg(struct tegra_dma_channel *tdc)
 
 	/* Configure next transfer immediately after DMA is busy */
 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
-			tdc->chan_base_offset + TEGRA_GPCDMA_CHAN_STATUS,
+			tdc->chan_base_offset + tdc->regs->status,
 			val,
 			(val & TEGRA_GPCDMA_STATUS_BUSY), 0,
 			TEGRA_GPCDMA_BURST_COMPLETION_TIMEOUT);
 	if (ret)
 		return;
 
-	ch_regs = &dma_desc->sg_req[dma_desc->sg_idx].ch_regs;
+	sg_req = &dma_desc->sg_req[dma_desc->sg_idx];
 
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_WCOUNT, ch_regs->wcount);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_regs->src_ptr);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_regs->dst_ptr);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR, ch_regs->high_addr_ptr);
+	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);
 
 	/* Start DMA */
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
-		  ch_regs->csr | TEGRA_GPCDMA_CSR_ENB);
+	tdc_write(tdc, tdc->regs->csr,
+		  sg_req->csr | TEGRA_GPCDMA_CSR_ENB);
 }
 
 static void tegra_dma_start(struct tegra_dma_channel *tdc)
 {
 	struct tegra_dma_desc *dma_desc = tdc->dma_desc;
-	struct tegra_dma_channel_regs *ch_regs;
+	struct tegra_dma_sg_req *sg_req;
 	struct virt_dma_desc *vdesc;
 
 	if (!dma_desc) {
@@ -526,21 +508,21 @@ static void tegra_dma_start(struct tegra_dma_channel *tdc)
 		tegra_dma_resume(tdc);
 	}
 
-	ch_regs = &dma_desc->sg_req[dma_desc->sg_idx].ch_regs;
+	sg_req = &dma_desc->sg_req[dma_desc->sg_idx];
 
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_WCOUNT, ch_regs->wcount);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, 0);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_SRC_PTR, ch_regs->src_ptr);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_DST_PTR, ch_regs->dst_ptr);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_HIGH_ADDR_PTR, ch_regs->high_addr_ptr);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_FIXED_PATTERN, ch_regs->fixed_pattern);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MMIOSEQ, ch_regs->mmio_seq);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, ch_regs->mc_seq);
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, ch_regs->csr);
+	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);
+	tdc_write(tdc, tdc->regs->csr, sg_req->csr);
 
 	/* Start DMA */
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR,
-		  ch_regs->csr | TEGRA_GPCDMA_CSR_ENB);
+	tdc_write(tdc, tdc->regs->csr,
+		  sg_req->csr | TEGRA_GPCDMA_CSR_ENB);
 }
 
 static void tegra_dma_xfer_complete(struct tegra_dma_channel *tdc)
@@ -601,19 +583,19 @@ static irqreturn_t tegra_dma_isr(int irq, void *dev_id)
 	u32 status;
 
 	/* Check channel error status register */
-	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS);
+	status = tdc_read(tdc, tdc->regs->err_status);
 	if (status) {
 		tegra_dma_chan_decode_error(tdc, status);
 		tegra_dma_dump_chan_regs(tdc);
-		tdc_write(tdc, TEGRA_GPCDMA_CHAN_ERR_STATUS, 0xFFFFFFFF);
+		tdc_write(tdc, tdc->regs->err_status, 0xFFFFFFFF);
 	}
 
 	spin_lock(&tdc->vc.lock);
-	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+	status = tdc_read(tdc, tdc->regs->status);
 	if (!(status & TEGRA_GPCDMA_STATUS_ISE_EOC))
 		goto irq_done;
 
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_STATUS,
+	tdc_write(tdc, tdc->regs->status,
 		  TEGRA_GPCDMA_STATUS_ISE_EOC);
 
 	if (!dma_desc)
@@ -673,10 +655,10 @@ static int tegra_dma_stop_client(struct tegra_dma_channel *tdc)
 	 * to stop DMA engine from starting any more bursts for
 	 * the given client and wait for in flight bursts to complete
 	 */
-	csr = tdc_read(tdc, TEGRA_GPCDMA_CHAN_CSR);
+	csr = tdc_read(tdc, tdc->regs->csr);
 	csr &= ~(TEGRA_GPCDMA_CSR_REQ_SEL_MASK);
 	csr |= TEGRA_GPCDMA_CSR_REQ_SEL_UNUSED;
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_CSR, csr);
+	tdc_write(tdc, tdc->regs->csr, csr);
 
 	/* Wait for in flight data transfer to finish */
 	udelay(TEGRA_GPCDMA_BURST_COMPLETE_TIME);
@@ -687,7 +669,7 @@ static int tegra_dma_stop_client(struct tegra_dma_channel *tdc)
 
 	ret = readl_relaxed_poll_timeout_atomic(tdc->tdma->base_addr +
 				tdc->chan_base_offset +
-				TEGRA_GPCDMA_CHAN_STATUS,
+				tdc->regs->status,
 				status,
 				!(status & (TEGRA_GPCDMA_STATUS_CHANNEL_TX |
 				TEGRA_GPCDMA_STATUS_CHANNEL_RX)),
@@ -739,14 +721,14 @@ static int tegra_dma_get_residual(struct tegra_dma_channel *tdc)
 	unsigned int bytes_xfer, residual;
 	u32 wcount = 0, status;
 
-	wcount = tdc_read(tdc, TEGRA_GPCDMA_CHAN_XFER_COUNT);
+	wcount = tdc_read(tdc, tdc->regs->wxfer);
 
 	/*
 	 * Set wcount = 0 if EOC bit is set. The transfer would have
 	 * already completed and the CHAN_XFER_COUNT could have updated
 	 * for the next transfer, specifically in case of cyclic transfers.
 	 */
-	status = tdc_read(tdc, TEGRA_GPCDMA_CHAN_STATUS);
+	status = tdc_read(tdc, tdc->regs->status);
 	if (status & TEGRA_GPCDMA_STATUS_ISE_EOC)
 		wcount = 0;
 
@@ -893,7 +875,7 @@ tegra_dma_prep_dma_memset(struct dma_chan *dc, dma_addr_t dest, int value,
 	/* Configure default priority weight for the channel */
 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
 
-	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+	mc_seq =  tdc_read(tdc, tdc->regs->mc_seq);
 	/* retain stream-id and clean rest */
 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
 
@@ -916,16 +898,16 @@ tegra_dma_prep_dma_memset(struct dma_chan *dc, dma_addr_t dest, int value,
 	dma_desc->sg_count = 1;
 	sg_req = dma_desc->sg_req;
 
-	sg_req[0].ch_regs.src_ptr = 0;
-	sg_req[0].ch_regs.dst_ptr = dest;
-	sg_req[0].ch_regs.high_addr_ptr =
+	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].ch_regs.fixed_pattern = value;
+	sg_req[0].fixed_pattern = value;
 	/* Word count reg takes value as (N +1) words */
-	sg_req[0].ch_regs.wcount = ((len - 4) >> 2);
-	sg_req[0].ch_regs.csr = csr;
-	sg_req[0].ch_regs.mmio_seq = 0;
-	sg_req[0].ch_regs.mc_seq = mc_seq;
+	sg_req[0].wcount = ((len - 4) >> 2);
+	sg_req[0].csr = csr;
+	sg_req[0].mmio_seq = 0;
+	sg_req[0].mc_seq = mc_seq;
 	sg_req[0].len = len;
 
 	dma_desc->cyclic = false;
@@ -961,7 +943,7 @@ tegra_dma_prep_dma_memcpy(struct dma_chan *dc, dma_addr_t dest,
 	/* Configure default priority weight for the channel */
 	csr |= FIELD_PREP(TEGRA_GPCDMA_CSR_WEIGHT, 1);
 
-	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+	mc_seq =  tdc_read(tdc, tdc->regs->mc_seq);
 	/* retain stream-id and clean rest */
 	mc_seq &= (TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK) |
 		  (TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK);
@@ -985,17 +967,17 @@ tegra_dma_prep_dma_memcpy(struct dma_chan *dc, dma_addr_t dest,
 	dma_desc->sg_count = 1;
 	sg_req = dma_desc->sg_req;
 
-	sg_req[0].ch_regs.src_ptr = src;
-	sg_req[0].ch_regs.dst_ptr = dest;
-	sg_req[0].ch_regs.high_addr_ptr =
+	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].ch_regs.high_addr_ptr |=
+	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].ch_regs.wcount = ((len - 4) >> 2);
-	sg_req[0].ch_regs.csr = csr;
-	sg_req[0].ch_regs.mmio_seq = 0;
-	sg_req[0].ch_regs.mc_seq = mc_seq;
+	sg_req[0].wcount = ((len - 4) >> 2);
+	sg_req[0].csr = csr;
+	sg_req[0].mmio_seq = 0;
+	sg_req[0].mc_seq = mc_seq;
 	sg_req[0].len = len;
 
 	dma_desc->cyclic = false;
@@ -1049,7 +1031,7 @@ tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
 	if (flags & DMA_PREP_INTERRUPT)
 		csr |= TEGRA_GPCDMA_CSR_IE_EOC;
 
-	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+	mc_seq =  tdc_read(tdc, tdc->regs->mc_seq);
 	/* retain stream-id and clean rest */
 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
 
@@ -1096,14 +1078,14 @@ tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
 		dma_desc->bytes_req += len;
 
 		if (direction == DMA_MEM_TO_DEV) {
-			sg_req[i].ch_regs.src_ptr = mem;
-			sg_req[i].ch_regs.dst_ptr = apb_ptr;
-			sg_req[i].ch_regs.high_addr_ptr =
+			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].ch_regs.src_ptr = apb_ptr;
-			sg_req[i].ch_regs.dst_ptr = mem;
-			sg_req[i].ch_regs.high_addr_ptr =
+			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));
 		}
 
@@ -1111,10 +1093,10 @@ tegra_dma_prep_slave_sg(struct dma_chan *dc, struct scatterlist *sgl,
 		 * Word count register takes input in words. Writing a value
 		 * of N into word count register means a req of (N+1) words.
 		 */
-		sg_req[i].ch_regs.wcount = ((len - 4) >> 2);
-		sg_req[i].ch_regs.csr = csr;
-		sg_req[i].ch_regs.mmio_seq = mmio_seq;
-		sg_req[i].ch_regs.mc_seq = mc_seq;
+		sg_req[i].wcount = ((len - 4) >> 2);
+		sg_req[i].csr = csr;
+		sg_req[i].mmio_seq = mmio_seq;
+		sg_req[i].mc_seq = mc_seq;
 		sg_req[i].len = len;
 	}
 
@@ -1186,7 +1168,7 @@ tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_l
 
 	mmio_seq |= FIELD_PREP(TEGRA_GPCDMA_MMIOSEQ_WRAP_WORD, 1);
 
-	mc_seq =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+	mc_seq =  tdc_read(tdc, tdc->regs->mc_seq);
 	/* retain stream-id and clean rest */
 	mc_seq &= TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK;
 
@@ -1217,24 +1199,24 @@ tegra_dma_prep_dma_cyclic(struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_l
 	for (i = 0; i < period_count; i++) {
 		mmio_seq |= get_burst_size(tdc, burst_size, slave_bw, len);
 		if (direction == DMA_MEM_TO_DEV) {
-			sg_req[i].ch_regs.src_ptr = mem;
-			sg_req[i].ch_regs.dst_ptr = apb_ptr;
-			sg_req[i].ch_regs.high_addr_ptr =
+			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].ch_regs.src_ptr = apb_ptr;
-			sg_req[i].ch_regs.dst_ptr = mem;
-			sg_req[i].ch_regs.high_addr_ptr =
+			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
 		 * of N into word count register means a req of (N+1) words.
 		 */
-		sg_req[i].ch_regs.wcount = ((len - 4) >> 2);
-		sg_req[i].ch_regs.csr = csr;
-		sg_req[i].ch_regs.mmio_seq = mmio_seq;
-		sg_req[i].ch_regs.mc_seq = mc_seq;
+		sg_req[i].wcount = ((len - 4) >> 2);
+		sg_req[i].csr = csr;
+		sg_req[i].mmio_seq = mmio_seq;
+		sg_req[i].mc_seq = mc_seq;
 		sg_req[i].len = len;
 
 		mem += len;
@@ -1304,11 +1286,28 @@ static struct dma_chan *tegra_dma_of_xlate(struct of_phandle_args *dma_spec,
 	return chan;
 }
 
+static const struct tegra_dma_channel_regs tegra186_reg_offsets = {
+	.csr = 0x0,
+	.status = 0x4,
+	.csre = 0x8,
+	.src = 0xc,
+	.dst = 0x10,
+	.high_addr = 0x14,
+	.mc_seq = 0x18,
+	.mmio_seq = 0x1c,
+	.wcount = 0x20,
+	.wxfer = 0x24,
+	.wstatus = 0x28,
+	.err_status = 0x30,
+	.fixed_pattern = 0x34,
+};
+
 static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
 	.nr_channels = 32,
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = false,
+	.channel_regs = &tegra186_reg_offsets,
 	.terminate = tegra_dma_stop_client,
 };
 
@@ -1317,6 +1316,7 @@ static const struct tegra_dma_chip_data tegra194_dma_chip_data = {
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = true,
+	.channel_regs = &tegra186_reg_offsets,
 	.terminate = tegra_dma_pause,
 };
 
@@ -1325,6 +1325,7 @@ static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
 	.channel_reg_size = SZ_64K,
 	.max_dma_count = SZ_1G,
 	.hw_support_pause = true,
+	.channel_regs = &tegra186_reg_offsets,
 	.terminate = tegra_dma_pause_noerr,
 };
 
@@ -1345,7 +1346,7 @@ MODULE_DEVICE_TABLE(of, tegra_dma_of_match);
 
 static int tegra_dma_program_sid(struct tegra_dma_channel *tdc, int stream_id)
 {
-	unsigned int reg_val =  tdc_read(tdc, TEGRA_GPCDMA_CHAN_MCSEQ);
+	unsigned int reg_val =  tdc_read(tdc, tdc->regs->mc_seq);
 
 	reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK);
 	reg_val &= ~(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK);
@@ -1353,7 +1354,7 @@ static int tegra_dma_program_sid(struct tegra_dma_channel *tdc, int stream_id)
 	reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID0_MASK, stream_id);
 	reg_val |= FIELD_PREP(TEGRA_GPCDMA_MCSEQ_STREAM_ID1_MASK, stream_id);
 
-	tdc_write(tdc, TEGRA_GPCDMA_CHAN_MCSEQ, reg_val);
+	tdc_write(tdc, tdc->regs->mc_seq, reg_val);
 	return 0;
 }
 
@@ -1419,6 +1420,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
 		tdc->chan_base_offset = TEGRA_GPCDMA_CHANNEL_BASE_ADDR_OFFSET +
 					i * cdata->channel_reg_size;
 		snprintf(tdc->name, sizeof(tdc->name), "gpcdma.%d", i);
+		tdc->regs = cdata->channel_regs;
 		tdc->tdma = tdma;
 		tdc->id = i;
 		tdc->slave_id = -1;
-- 
2.50.1

[PATCH v5 06/10] dmaengine: tegra: Support address width > 39 bits

[Akhil R]

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

[PATCH v5 07/10] dmaengine: tegra: Use managed DMA controller registration

[Akhil R]

Switch to managed registration in probe. This simplifies the error
paths in the probe and also removes the requirement of the driver
remove function.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Suggested-by: Frank Li <frank.li@nxp.com>
---
 drivers/dma/tegra186-gpc-dma.c | 19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index 3ac43ad19ed6..9bea2ffb3b9e 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -1483,37 +1483,27 @@ static int tegra_dma_probe(struct platform_device *pdev)
 	tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize;
 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 
-	ret = dma_async_device_register(&tdma->dma_dev);
+	ret = dmaenginem_async_device_register(&tdma->dma_dev);
 	if (ret < 0) {
 		dev_err_probe(&pdev->dev, ret,
 			      "GPC DMA driver registration failed\n");
 		return ret;
 	}
 
-	ret = of_dma_controller_register(pdev->dev.of_node,
-					 tegra_dma_of_xlate, tdma);
+	ret = devm_of_dma_controller_register(&pdev->dev, pdev->dev.of_node,
+					      tegra_dma_of_xlate, tdma);
 	if (ret < 0) {
 		dev_err_probe(&pdev->dev, ret,
 			      "GPC DMA OF registration failed\n");
-
-		dma_async_device_unregister(&tdma->dma_dev);
 		return ret;
 	}
 
-	dev_info(&pdev->dev, "GPC DMA driver register %lu channels\n",
+	dev_info(&pdev->dev, "GPC DMA driver registered %lu channels\n",
 		 hweight_long(tdma->chan_mask));
 
 	return 0;
 }
 
-static void tegra_dma_remove(struct platform_device *pdev)
-{
-	struct tegra_dma *tdma = platform_get_drvdata(pdev);
-
-	of_dma_controller_free(pdev->dev.of_node);
-	dma_async_device_unregister(&tdma->dma_dev);
-}
-
 static int __maybe_unused tegra_dma_pm_suspend(struct device *dev)
 {
 	struct tegra_dma *tdma = dev_get_drvdata(dev);
@@ -1564,7 +1554,6 @@ static struct platform_driver tegra_dma_driver = {
 		.of_match_table = tegra_dma_of_match,
 	},
 	.probe		= tegra_dma_probe,
-	.remove		= tegra_dma_remove,
 };
 
 module_platform_driver(tegra_dma_driver);
-- 
2.50.1

[PATCH v5 08/10] dmaengine: tegra: Use iommu-map for stream ID

[Akhil R]

Use 'iommu-map', when provided, to get the stream ID to be programmed
for each channel. Iterate over the channels registered and configure
each channel device separately using of_dma_configure_id() to allow
it to use a separate IOMMU domain for the transfer. However, do this
in a second loop since the first loop populates the DMA device channels
list and async_device_register() registers the channels. Both are
prerequisites for using the channel device in the next loop.

Channels will continue to use the same global stream ID if the
'iommu-map' property is not present in the device tree.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
---
 drivers/dma/tegra186-gpc-dma.c | 57 ++++++++++++++++++++++++++++------
 1 file changed, 48 insertions(+), 9 deletions(-)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index 9bea2ffb3b9e..64743d852dda 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -15,6 +15,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_dma.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
 #include <linux/slab.h>
@@ -1380,9 +1381,13 @@ static int tegra_dma_program_sid(struct tegra_dma_channel *tdc, int stream_id)
 static int tegra_dma_probe(struct platform_device *pdev)
 {
 	const struct tegra_dma_chip_data *cdata = NULL;
+	struct tegra_dma_channel *tdc;
+	struct tegra_dma *tdma;
+	struct dma_chan *chan;
+	struct device *chdev;
+	bool use_iommu_map = false;
 	unsigned int i;
 	u32 stream_id;
-	struct tegra_dma *tdma;
 	int ret;
 
 	cdata = of_device_get_match_data(&pdev->dev);
@@ -1410,9 +1415,12 @@ static int tegra_dma_probe(struct platform_device *pdev)
 
 	tdma->dma_dev.dev = &pdev->dev;
 
-	if (!tegra_dev_iommu_get_stream_id(&pdev->dev, &stream_id)) {
-		dev_err(&pdev->dev, "Missing iommu stream-id\n");
-		return -EINVAL;
+	use_iommu_map = of_property_present(pdev->dev.of_node, "iommu-map");
+	if (!use_iommu_map) {
+		if (!tegra_dev_iommu_get_stream_id(&pdev->dev, &stream_id)) {
+			dev_err(&pdev->dev, "Missing iommu stream-id\n");
+			return -EINVAL;
+		}
 	}
 
 	ret = device_property_read_u32(&pdev->dev, "dma-channel-mask",
@@ -1424,9 +1432,10 @@ static int tegra_dma_probe(struct platform_device *pdev)
 		tdma->chan_mask = TEGRA_GPCDMA_DEFAULT_CHANNEL_MASK;
 	}
 
+	/* Initialize vchan for each channel and populate the channels list */
 	INIT_LIST_HEAD(&tdma->dma_dev.channels);
 	for (i = 0; i < cdata->nr_channels; i++) {
-		struct tegra_dma_channel *tdc = &tdma->channels[i];
+		tdc = &tdma->channels[i];
 
 		/* Check for channel mask */
 		if (!(tdma->chan_mask & BIT(i)))
@@ -1446,10 +1455,6 @@ static int tegra_dma_probe(struct platform_device *pdev)
 
 		vchan_init(&tdc->vc, &tdma->dma_dev);
 		tdc->vc.desc_free = tegra_dma_desc_free;
-
-		/* program stream-id for this channel */
-		tegra_dma_program_sid(tdc, stream_id);
-		tdc->stream_id = stream_id;
 	}
 
 	dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(cdata->addr_bits));
@@ -1483,6 +1488,7 @@ static int tegra_dma_probe(struct platform_device *pdev)
 	tdma->dma_dev.device_synchronize = tegra_dma_chan_synchronize;
 	tdma->dma_dev.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
 
+	/* Register the DMA device and the channels */
 	ret = dmaenginem_async_device_register(&tdma->dma_dev);
 	if (ret < 0) {
 		dev_err_probe(&pdev->dev, ret,
@@ -1490,6 +1496,39 @@ static int tegra_dma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/*
+	 * Configure stream ID for each channel from the channels registered
+	 * above. This is done in a separate iteration to ensure that only
+	 * the channels available and registered for the DMA device are used.
+	 */
+	list_for_each_entry(chan, &tdma->dma_dev.channels, device_node) {
+		chdev = &chan->dev->device;
+		tdc = to_tegra_dma_chan(chan);
+
+		if (use_iommu_map) {
+			chdev->bus = pdev->dev.bus;
+			dma_coerce_mask_and_coherent(chdev, DMA_BIT_MASK(cdata->addr_bits));
+
+			ret = of_dma_configure_id(chdev, pdev->dev.of_node,
+						  true, &tdc->id);
+			if (ret)
+				return dev_err_probe(chdev, ret,
+					   "Failed to configure IOMMU for channel %d", tdc->id);
+
+			if (!tegra_dev_iommu_get_stream_id(chdev, &stream_id)) {
+				dev_err(chdev, "Failed to get stream ID for channel %d\n",
+					tdc->id);
+				return -EINVAL;
+			}
+
+			chan->dev->chan_dma_dev = true;
+		}
+
+		/* program stream-id for this channel */
+		tegra_dma_program_sid(tdc, stream_id);
+		tdc->stream_id = stream_id;
+	}
+
 	ret = devm_of_dma_controller_register(&pdev->dev, pdev->dev.of_node,
 					      tegra_dma_of_xlate, tdma);
 	if (ret < 0) {
-- 
2.50.1

Re: [PATCH v5 08/10] dmaengine: tegra: Use iommu-map for stream ID

[Frank Li]

On Mon, Mar 30, 2026 at 08:14:54PM +0530, Akhil R wrote:
> Use 'iommu-map', when provided, to get the stream ID to be programmed
> for each channel. Iterate over the channels registered and configure
> each channel device separately using of_dma_configure_id() to allow
> it to use a separate IOMMU domain for the transfer. However, do this
> in a second loop since the first loop populates the DMA device channels
> list and async_device_register() registers the channels. Both are
> prerequisites for using the channel device in the next loop.
>
> Channels will continue to use the same global stream ID if the
> 'iommu-map' property is not present in the device tree.
>
> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
> ---
...
>
> +	/*
> +	 * Configure stream ID for each channel from the channels registered
> +	 * above. This is done in a separate iteration to ensure that only
> +	 * the channels available and registered for the DMA device are used.
> +	 */
> +	list_for_each_entry(chan, &tdma->dma_dev.channels, device_node) {
> +		chdev = &chan->dev->device;
> +		tdc = to_tegra_dma_chan(chan);
> +
> +		if (use_iommu_map) {
> +			chdev->bus = pdev->dev.bus;
> +			dma_coerce_mask_and_coherent(chdev, DMA_BIT_MASK(cdata->addr_bits));
> +
> +			ret = of_dma_configure_id(chdev, pdev->dev.of_node,
> +						  true, &tdc->id);
> +			if (ret)
> +				return dev_err_probe(chdev, ret,
> +					   "Failed to configure IOMMU for channel %d", tdc->id);
> +
> +			if (!tegra_dev_iommu_get_stream_id(chdev, &stream_id)) {
> +				dev_err(chdev, "Failed to get stream ID for channel %d\n",
> +					tdc->id);
> +				return -EINVAL;

Can you check similar problem before post patch, here also can use
	return dev_err_probe()

Frank
> +			}
> +
> +			chan->dev->chan_dma_dev = true;
> +		}
> +
> +		/* program stream-id for this channel */
> +		tegra_dma_program_sid(tdc, stream_id);
> +		tdc->stream_id = stream_id;
> +	}
> +
>  	ret = devm_of_dma_controller_register(&pdev->dev, pdev->dev.of_node,
>  					      tegra_dma_of_xlate, tdma);
>  	if (ret < 0) {
> --
> 2.50.1
>

Re: [PATCH v5 08/10] dmaengine: tegra: Use iommu-map for stream ID

[Akhil R]

On Mon, 30 Mar 2026 12:47:24 -0400, Frank Li wrote:
> On Mon, Mar 30, 2026 at 08:14:54PM +0530, Akhil R wrote:
>> Use 'iommu-map', when provided, to get the stream ID to be programmed
>> for each channel. Iterate over the channels registered and configure
>> each channel device separately using of_dma_configure_id() to allow
>> it to use a separate IOMMU domain for the transfer. However, do this
>> in a second loop since the first loop populates the DMA device channels
>> list and async_device_register() registers the channels. Both are
>> prerequisites for using the channel device in the next loop.
>>
>> Channels will continue to use the same global stream ID if the
>> 'iommu-map' property is not present in the device tree.
>>
>> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
>> ---
> ...
>>
>> +	/*
>> +	 * Configure stream ID for each channel from the channels registered
>> +	 * above. This is done in a separate iteration to ensure that only
>> +	 * the channels available and registered for the DMA device are used.
>> +	 */
>> +	list_for_each_entry(chan, &tdma->dma_dev.channels, device_node) {
>> +		chdev = &chan->dev->device;
>> +		tdc = to_tegra_dma_chan(chan);
>> +
>> +		if (use_iommu_map) {
>> +			chdev->bus = pdev->dev.bus;
>> +			dma_coerce_mask_and_coherent(chdev, DMA_BIT_MASK(cdata->addr_bits));
>> +
>> +			ret = of_dma_configure_id(chdev, pdev->dev.of_node,
>> +						  true, &tdc->id);
>> +			if (ret)
>> +				return dev_err_probe(chdev, ret,
>> +					   "Failed to configure IOMMU for channel %d", tdc->id);
>> +
>> +			if (!tegra_dev_iommu_get_stream_id(chdev, &stream_id)) {
>> +				dev_err(chdev, "Failed to get stream ID for channel %d\n",
>> +					tdc->id);
>> +				return -EINVAL;
> 
> Can you check similar problem before post patch, here also can use
> 	return dev_err_probe()

I did notice that, but I thought dev_err_probe is to handle -EPROBE_DEFER
and we do not use it when we return a fixed value. It returns -EINVAL here
directly.

Best Regards,
Akhil

Re: [PATCH v5 08/10] dmaengine: tegra: Use iommu-map for stream ID

[Frank Li]

On Mon, Mar 30, 2026 at 11:32:40PM +0530, Akhil R wrote:
> On Mon, 30 Mar 2026 12:47:24 -0400, Frank Li wrote:
> > On Mon, Mar 30, 2026 at 08:14:54PM +0530, Akhil R wrote:
> >> Use 'iommu-map', when provided, to get the stream ID to be programmed
> >> for each channel. Iterate over the channels registered and configure
> >> each channel device separately using of_dma_configure_id() to allow
> >> it to use a separate IOMMU domain for the transfer. However, do this
> >> in a second loop since the first loop populates the DMA device channels
> >> list and async_device_register() registers the channels. Both are
> >> prerequisites for using the channel device in the next loop.
> >>
> >> Channels will continue to use the same global stream ID if the
> >> 'iommu-map' property is not present in the device tree.
> >>
> >> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
> >> ---
> > ...
> >>
> >> +	/*
> >> +	 * Configure stream ID for each channel from the channels registered
> >> +	 * above. This is done in a separate iteration to ensure that only
> >> +	 * the channels available and registered for the DMA device are used.
> >> +	 */
> >> +	list_for_each_entry(chan, &tdma->dma_dev.channels, device_node) {
> >> +		chdev = &chan->dev->device;
> >> +		tdc = to_tegra_dma_chan(chan);
> >> +
> >> +		if (use_iommu_map) {
> >> +			chdev->bus = pdev->dev.bus;
> >> +			dma_coerce_mask_and_coherent(chdev, DMA_BIT_MASK(cdata->addr_bits));
> >> +
> >> +			ret = of_dma_configure_id(chdev, pdev->dev.of_node,
> >> +						  true, &tdc->id);
> >> +			if (ret)
> >> +				return dev_err_probe(chdev, ret,
> >> +					   "Failed to configure IOMMU for channel %d", tdc->id);
> >> +
> >> +			if (!tegra_dev_iommu_get_stream_id(chdev, &stream_id)) {
> >> +				dev_err(chdev, "Failed to get stream ID for channel %d\n",
> >> +					tdc->id);
> >> +				return -EINVAL;
> >
> > Can you check similar problem before post patch, here also can use
> > 	return dev_err_probe()
>
> I did notice that, but I thought dev_err_probe is to handle -EPROBE_DEFER
> and we do not use it when we return a fixed value. It returns -EINVAL here
> directly.

even that, still can use return dev_err_probe(chddev, -EINVAL, ...) to
short your code.

Frank

>
> Best Regards,
> Akhil

Re: [PATCH v5 08/10] dmaengine: tegra: Use iommu-map for stream ID

[Akhil R]

On Mon, 30 Mar 2026 14:15:43 -0400, Frank Li wrote:
> On Mon, Mar 30, 2026 at 11:32:40PM +0530, Akhil R wrote:
>> On Mon, 30 Mar 2026 12:47:24 -0400, Frank Li wrote:
>> > On Mon, Mar 30, 2026 at 08:14:54PM +0530, Akhil R wrote:
>> >> Use 'iommu-map', when provided, to get the stream ID to be programmed
>> >> for each channel. Iterate over the channels registered and configure
>> >> each channel device separately using of_dma_configure_id() to allow
>> >> it to use a separate IOMMU domain for the transfer. However, do this
>> >> in a second loop since the first loop populates the DMA device channels
>> >> list and async_device_register() registers the channels. Both are
>> >> prerequisites for using the channel device in the next loop.
>> >>
>> >> Channels will continue to use the same global stream ID if the
>> >> 'iommu-map' property is not present in the device tree.
>> >>
>> >> Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
>> >> ---
>> > ...
>> >>
>> >> +	/*
>> >> +	 * Configure stream ID for each channel from the channels registered
>> >> +	 * above. This is done in a separate iteration to ensure that only
>> >> +	 * the channels available and registered for the DMA device are used.
>> >> +	 */
>> >> +	list_for_each_entry(chan, &tdma->dma_dev.channels, device_node) {
>> >> +		chdev = &chan->dev->device;
>> >> +		tdc = to_tegra_dma_chan(chan);
>> >> +
>> >> +		if (use_iommu_map) {
>> >> +			chdev->bus = pdev->dev.bus;
>> >> +			dma_coerce_mask_and_coherent(chdev, DMA_BIT_MASK(cdata->addr_bits));
>> >> +
>> >> +			ret = of_dma_configure_id(chdev, pdev->dev.of_node,
>> >> +						  true, &tdc->id);
>> >> +			if (ret)
>> >> +				return dev_err_probe(chdev, ret,
>> >> +					   "Failed to configure IOMMU for channel %d", tdc->id);
>> >> +
>> >> +			if (!tegra_dev_iommu_get_stream_id(chdev, &stream_id)) {
>> >> +				dev_err(chdev, "Failed to get stream ID for channel %d\n",
>> >> +					tdc->id);
>> >> +				return -EINVAL;
>> >
>> > Can you check similar problem before post patch, here also can use
>> > 	return dev_err_probe()
>>
>> I did notice that, but I thought dev_err_probe is to handle -EPROBE_DEFER
>> and we do not use it when we return a fixed value. It returns -EINVAL here
>> directly.
> 
> even that, still can use return dev_err_probe(chddev, -EINVAL, ...) to
> short your code.

I just saw in the dev_err_probe() description that it is not limited to
-EPROBE_DEFER. Thanks for pointing. I will update the patch.
 
Best Regards,
Akhil

[PATCH v5 09/10] dmaengine: tegra: Add Tegra264 support

[Akhil R]

Add compatible and chip data to support GPCDMA in Tegra264, which has
differences in register layout and address bits compared to previous
versions.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/tegra186-gpc-dma.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/dma/tegra186-gpc-dma.c b/drivers/dma/tegra186-gpc-dma.c
index 64743d852dda..0b7faf8bb80b 100644
--- a/drivers/dma/tegra186-gpc-dma.c
+++ b/drivers/dma/tegra186-gpc-dma.c
@@ -1319,6 +1319,23 @@ static const struct tegra_dma_channel_regs tegra186_reg_offsets = {
 	.fixed_pattern = 0x34,
 };
 
+static const struct tegra_dma_channel_regs tegra264_reg_offsets = {
+	.csr = 0x0,
+	.status = 0x4,
+	.csre = 0x8,
+	.src = 0xc,
+	.dst = 0x10,
+	.src_high = 0x14,
+	.dst_high = 0x18,
+	.mc_seq = 0x1c,
+	.mmio_seq = 0x20,
+	.wcount = 0x24,
+	.wxfer = 0x28,
+	.wstatus = 0x2c,
+	.err_status = 0x34,
+	.fixed_pattern = 0x38,
+};
+
 static const struct tegra_dma_chip_data tegra186_dma_chip_data = {
 	.nr_channels = 32,
 	.addr_bits = 39,
@@ -1349,6 +1366,16 @@ static const struct tegra_dma_chip_data tegra234_dma_chip_data = {
 	.terminate = tegra_dma_pause_noerr,
 };
 
+static const struct tegra_dma_chip_data tegra264_dma_chip_data = {
+	.nr_channels = 32,
+	.addr_bits = 41,
+	.channel_reg_size = SZ_64K,
+	.max_dma_count = SZ_1G,
+	.hw_support_pause = true,
+	.channel_regs = &tegra264_reg_offsets,
+	.terminate = tegra_dma_pause_noerr,
+};
+
 static const struct of_device_id tegra_dma_of_match[] = {
 	{
 		.compatible = "nvidia,tegra186-gpcdma",
@@ -1359,6 +1386,9 @@ static const struct of_device_id tegra_dma_of_match[] = {
 	}, {
 		.compatible = "nvidia,tegra234-gpcdma",
 		.data = &tegra234_dma_chip_data,
+	}, {
+		.compatible = "nvidia,tegra264-gpcdma",
+		.data = &tegra264_dma_chip_data,
 	}, {
 	},
 };
-- 
2.50.1

[PATCH v5 10/10] arm64: tegra: Enable GPCDMA in Tegra264 and add iommu-map

[Akhil R]

Enable GPCDMA in Tegra264 and add the iommu-map property so that each
channel uses a separate stream ID and gets its own IOMMU domain for
memory.

Signed-off-by: Akhil R <akhilrajeev@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi | 4 ++++
 arch/arm64/boot/dts/nvidia/tegra264.dtsi       | 1 +
 2 files changed, 5 insertions(+)

diff --git a/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi b/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
index 7e2c3e66c2ab..58cd81bc33d7 100644
--- a/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra264-p3834.dtsi
@@ -9,6 +9,10 @@ aliases {
 	};
 
 	bus@0 {
+		dma-controller@8400000 {
+			status = "okay";
+		};
+
 		serial@c4e0000 {
 			status = "okay";
 		};
diff --git a/arch/arm64/boot/dts/nvidia/tegra264.dtsi b/arch/arm64/boot/dts/nvidia/tegra264.dtsi
index af077420d7d9..b2f20d4b567a 100644
--- a/arch/arm64/boot/dts/nvidia/tegra264.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra264.dtsi
@@ -3244,6 +3244,7 @@ gpcdma: dma-controller@8400000 {
 				     <GIC_SPI 615 IRQ_TYPE_LEVEL_HIGH>;
 			#dma-cells = <1>;
 			iommus = <&smmu1 0x00000800>;
+			iommu-map = <1 &smmu1 0x801 31>;
 			dma-coherent;
 			dma-channel-mask = <0xfffffffe>;
 			status = "disabled";
-- 
2.50.1