Re: [PATCH v2 5/7] dmaengine: sun6i: Add support for H6 DMA

From: ClÃment PÃron
Date: Sun May 26 2019 - 15:16:03 EST


Hi Maxime,

On Sun, 26 May 2019 at 20:34, Maxime Ripard <maxime.ripard@xxxxxxxxxxx> wrote:
>
> On Sat, May 25, 2019 at 06:38:17PM +0200, ClÃment PÃron wrote:
> > From: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> >
> > H6 DMA has more than 32 supported DRQs, which means that configuration
> > register is slightly rearranged. It also needs additional clock to be
> > enabled.
> >
> > Add support for it.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> > Signed-off-by: ClÃment PÃron <peron.clem@xxxxxxxxx>
> > ---
> > drivers/dma/sun6i-dma.c | 44 +++++++++++++++++++++++++++++++++++++++--
> > 1 file changed, 42 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/dma/sun6i-dma.c b/drivers/dma/sun6i-dma.c
> > index f5cb5e89bf7b..8d44ddae926a 100644
> > --- a/drivers/dma/sun6i-dma.c
> > +++ b/drivers/dma/sun6i-dma.c
> > @@ -69,14 +69,19 @@
> >
> > #define DMA_CHAN_CUR_CFG 0x0c
> > #define DMA_CHAN_MAX_DRQ_A31 0x1f
> > +#define DMA_CHAN_MAX_DRQ_H6 0x3f
> > #define DMA_CHAN_CFG_SRC_DRQ_A31(x) ((x) & DMA_CHAN_MAX_DRQ_A31)
> > +#define DMA_CHAN_CFG_SRC_DRQ_H6(x) ((x) & DMA_CHAN_MAX_DRQ_H6)
> > #define DMA_CHAN_CFG_SRC_MODE_A31(x) (((x) & 0x1) << 5)
> > +#define DMA_CHAN_CFG_SRC_MODE_H6(x) (((x) & 0x1) << 8)
> > #define DMA_CHAN_CFG_SRC_BURST_A31(x) (((x) & 0x3) << 7)
> > #define DMA_CHAN_CFG_SRC_BURST_H3(x) (((x) & 0x3) << 6)
> > #define DMA_CHAN_CFG_SRC_WIDTH(x) (((x) & 0x3) << 9)
> >
> > #define DMA_CHAN_CFG_DST_DRQ_A31(x) (DMA_CHAN_CFG_SRC_DRQ_A31(x) << 16)
> > +#define DMA_CHAN_CFG_DST_DRQ_H6(x) (DMA_CHAN_CFG_SRC_DRQ_H6(x) << 16)
> > #define DMA_CHAN_CFG_DST_MODE_A31(x) (DMA_CHAN_CFG_SRC_MODE_A31(x) << 16)
> > +#define DMA_CHAN_CFG_DST_MODE_H6(x) (DMA_CHAN_CFG_SRC_MODE_H6(x) << 16)
> > #define DMA_CHAN_CFG_DST_BURST_A31(x) (DMA_CHAN_CFG_SRC_BURST_A31(x) << 16)
> > #define DMA_CHAN_CFG_DST_BURST_H3(x) (DMA_CHAN_CFG_SRC_BURST_H3(x) << 16)
> > #define DMA_CHAN_CFG_DST_WIDTH(x) (DMA_CHAN_CFG_SRC_WIDTH(x) << 16)
> > @@ -319,12 +324,24 @@ static void sun6i_set_drq_a31(u32 *p_cfg, s8 src_drq, s8 dst_drq)
> > DMA_CHAN_CFG_DST_DRQ_A31(dst_drq);
> > }
> >
> > +static void sun6i_set_drq_h6(u32 *p_cfg, s8 src_drq, s8 dst_drq)
> > +{
> > + *p_cfg |= DMA_CHAN_CFG_SRC_DRQ_H6(src_drq) |
> > + DMA_CHAN_CFG_DST_DRQ_H6(dst_drq);
> > +}
> > +
> > static void sun6i_set_mode_a31(u32 *p_cfg, s8 src_mode, s8 dst_mode)
> > {
> > *p_cfg |= DMA_CHAN_CFG_SRC_MODE_A31(src_mode) |
> > DMA_CHAN_CFG_DST_MODE_A31(dst_mode);
> > }
> >
> > +static void sun6i_set_mode_h6(u32 *p_cfg, s8 src_mode, s8 dst_mode)
> > +{
> > + *p_cfg |= DMA_CHAN_CFG_SRC_MODE_H6(src_mode) |
> > + DMA_CHAN_CFG_DST_MODE_H6(dst_mode);
> > +}
> > +
> > static size_t sun6i_get_chan_size(struct sun6i_pchan *pchan)
> > {
> > struct sun6i_desc *txd = pchan->desc;
> > @@ -1160,6 +1177,28 @@ static struct sun6i_dma_config sun50i_a64_dma_cfg = {
> > BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
> > };
> >
> > +/*
> > + * The H6 binding uses the number of dma channels from the
> > + * device tree node.
> > + */
> > +static struct sun6i_dma_config sun50i_h6_dma_cfg = {
> > + .clock_autogate_enable = sun6i_enable_clock_autogate_h3,
> > + .set_burst_length = sun6i_set_burst_length_h3,
> > + .set_drq = sun6i_set_drq_h6,
> > + .set_mode = sun6i_set_mode_h6,
> > + .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) |
> > + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
> > + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
> > + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
> > + .dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
> > + BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
> > + BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) |
> > + BIT(DMA_SLAVE_BUSWIDTH_8_BYTES),
> > + .has_mbus_clk = true,
> > +};
> > +
> > /*
> > * The V3s have only 8 physical channels, a maximum DRQ port id of 23,
> > * and a total of 24 usable source and destination endpoints.
> > @@ -1190,6 +1229,7 @@ static const struct of_device_id sun6i_dma_match[] = {
> > { .compatible = "allwinner,sun8i-h3-dma", .data = &sun8i_h3_dma_cfg },
> > { .compatible = "allwinner,sun8i-v3s-dma", .data = &sun8i_v3s_dma_cfg },
> > { .compatible = "allwinner,sun50i-a64-dma", .data = &sun50i_a64_dma_cfg },
> > + { .compatible = "allwinner,sun50i-h6-dma", .data = &sun50i_h6_dma_cfg },
> > { /* sentinel */ }
> > };
> > MODULE_DEVICE_TABLE(of, sun6i_dma_match);
> > @@ -1288,8 +1328,8 @@ static int sun6i_dma_probe(struct platform_device *pdev)
> > ret = of_property_read_u32(np, "dma-requests", &sdc->max_request);
> > if (ret && !sdc->max_request) {
> > dev_info(&pdev->dev, "Missing dma-requests, using %u.\n",
> > - DMA_CHAN_MAX_DRQ_A31);
> > - sdc->max_request = DMA_CHAN_MAX_DRQ_A31;
> > + DMA_CHAN_MAX_DRQ_H6);
> > + sdc->max_request = DMA_CHAN_MAX_DRQ_H6;
>
> This is changing the binding though, since we're changing the
> default. This should be reflected in the binding, and we should keep
> the same default in the device tree binding.

Agree, H6 device-tree will have the "dma-request" property.
As this modification is not mandatory, we can drop it to avoid
bindings modification.

What do you think?

Thanks for your review,
ClÃment

>
> Maxime
>
> --
> Maxime Ripard, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com