Re: [PATCH v2 2/5] dmaengine: sun6i-dma: Add set_addr function pointer for variable address widths

From: Frank Li

Date: Sun Jun 21 2026 - 18:17:10 EST


On Sun, Jun 21, 2026 at 09:40:55PM +0000, Yuanshen Cao wrote:
> The A733 DMA controller supports higher address (up to 32G) compared to
> previous generations. The existing `sun6i_dma_set_addr` function uses a
> hardcoded logic for setting the high-address bits in the LLI parameters.
>
> By moving `set_addr` into the `sun6i_dma_config` structure, we can
> provide specialized implementations for different hardware. This allows
> the A733 to use a version of `set_addr` that correctly handles its
> specific `SRC_HIGH_ADDR_32G` and `DST_HIGH_ADDR_32G` in the `set_addr`
> register later in the series.
>
> Changes:
> - Added `set_addr` function pointer to `struct sun6i_dma_config`.
> - Refactored `sun6i_dma_set_addr` and introduced
> `sun6i_dma_set_addr_a31/a100` (keeping the logic for previous
> generations).
> - Updated all existing configuration structs to include the new
> `set_addr` pointer.
> - Removed `has_high_addr` since the logic is replaced by
> `sun6i_dma_set_addr_a100`.
>
> Signed-off-by: Yuanshen Cao <alex.caoys@xxxxxxxxx>
> ---

Reviewed-by: Frank Li <Frank.Li@xxxxxxx>

> drivers/dma/sun6i-dma.c | 35 +++++++++++++++++++++++++++++------
> 1 file changed, 29 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
> index ef3052c4ab36..9984b9033cbb 100644
> --- a/drivers/dma/sun6i-dma.c
> +++ b/drivers/dma/sun6i-dma.c
> @@ -112,6 +112,7 @@
>
> /* forward declaration */
> struct sun6i_dma_dev;
> +struct sun6i_dma_lli;
>
> /*
> * Hardware channels / ports representation
> @@ -138,6 +139,8 @@ struct sun6i_dma_config {
> void (*set_burst_length)(u32 *p_cfg, s8 src_burst, s8 dst_burst);
> void (*set_drq)(u32 *p_cfg, s8 src_drq, s8 dst_drq);
> void (*set_mode)(u32 *p_cfg, s8 src_mode, s8 dst_mode);
> + void (*set_addr)(struct sun6i_dma_dev *sdev, struct sun6i_dma_lli *v_lli,
> + dma_addr_t src, dma_addr_t dst);
> void (*dump_com_regs)(struct sun6i_dma_dev *sdev);
> u32 (*read_irq_en)(struct sun6i_dma_dev *sdev, u32 irq_reg);
> void (*write_irq_en)(struct sun6i_dma_dev *sdev, u32 irq_reg, u32 irq_val);
> @@ -147,7 +150,6 @@ struct sun6i_dma_config {
> u32 dst_burst_lengths;
> u32 src_addr_widths;
> u32 dst_addr_widths;
> - bool has_high_addr;
> bool has_mbus_clk;
> };
>
> @@ -673,16 +675,30 @@ static int set_config(struct sun6i_dma_dev *sdev,
> return 0;
> }
>
> -static inline void sun6i_dma_set_addr(struct sun6i_dma_dev *sdev,
> +static void sun6i_dma_set_addr_a31(struct sun6i_dma_dev *sdev,
> + struct sun6i_dma_lli *v_lli,
> + dma_addr_t src, dma_addr_t dst)
> +{
> + v_lli->src = lower_32_bits(src);
> + v_lli->dst = lower_32_bits(dst);
> +}
> +
> +static void sun6i_dma_set_addr_a100(struct sun6i_dma_dev *sdev,
> struct sun6i_dma_lli *v_lli,
> dma_addr_t src, dma_addr_t dst)
> {
> v_lli->src = lower_32_bits(src);
> v_lli->dst = lower_32_bits(dst);
>
> - if (sdev->cfg->has_high_addr)
> - v_lli->para |= SRC_HIGH_ADDR(upper_32_bits(src)) |
> - DST_HIGH_ADDR(upper_32_bits(dst));
> + v_lli->para |= SRC_HIGH_ADDR(upper_32_bits(src)) |
> + DST_HIGH_ADDR(upper_32_bits(dst));
> +}
> +
> +static inline void sun6i_dma_set_addr(struct sun6i_dma_dev *sdev,
> + struct sun6i_dma_lli *v_lli,
> + dma_addr_t src, dma_addr_t dst)
> +{
> + sdev->cfg->set_addr(sdev, v_lli, src, dst);
> }
>
> static struct dma_async_tx_descriptor *sun6i_dma_prep_dma_memcpy(
> @@ -1156,6 +1172,7 @@ static struct sun6i_dma_config sun6i_a31_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_a31,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(8),
> .dst_burst_lengths = BIT(1) | BIT(8),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1180,6 +1197,7 @@ static struct sun6i_dma_config sun8i_a23_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_a31,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(8),
> .dst_burst_lengths = BIT(1) | BIT(8),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1199,6 +1217,7 @@ static struct sun6i_dma_config sun8i_a83t_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_a31,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(8),
> .dst_burst_lengths = BIT(1) | BIT(8),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1225,6 +1244,7 @@ static struct sun6i_dma_config sun8i_h3_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_h3,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1247,6 +1267,7 @@ static struct sun6i_dma_config sun50i_a64_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_h3,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1269,6 +1290,7 @@ static struct sun6i_dma_config sun50i_a100_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_h3,
> .set_drq = sun6i_set_drq_h6,
> .set_mode = sun6i_set_mode_h6,
> + .set_addr = sun6i_dma_set_addr_a100,
> .src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1279,7 +1301,6 @@ static struct sun6i_dma_config sun50i_a100_dma_cfg = {
> BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
> BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
> BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
> - .has_high_addr = true,
> .has_mbus_clk = true,
> SUN6I_DMA_IRQ_A31_COMMON_OPS
> };
> @@ -1293,6 +1314,7 @@ static struct sun6i_dma_config sun50i_h6_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_h3,
> .set_drq = sun6i_set_drq_h6,
> .set_mode = sun6i_set_mode_h6,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .dst_burst_lengths = BIT(1) | BIT(4) | BIT(8) | BIT(16),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> @@ -1320,6 +1342,7 @@ static struct sun6i_dma_config sun8i_v3s_dma_cfg = {
> .set_burst_length = sun6i_set_burst_length_a31,
> .set_drq = sun6i_set_drq_a31,
> .set_mode = sun6i_set_mode_a31,
> + .set_addr = sun6i_dma_set_addr_a31,
> .src_burst_lengths = BIT(1) | BIT(8),
> .dst_burst_lengths = BIT(1) | BIT(8),
> .src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
>
> --
> 2.54.0
>