Re: [PATCH 5/6] dmaengine: sun6i: Add support for H6 DMA

From: Jernej Åkrabec
Date: Sat Mar 16 2019 - 07:37:48 EST


Dne sobota, 16. marec 2019 ob 12:13:24 CET je Vinod Koul napisal(a):
> On 07-03-19, 17:58, Jernej Skrabec wrote:
> > H6 DMA has more than 32 supported DRQs, which means that configuration
> > register is slightly rearranged. It also needs additional clock to be
> > enabled.
>
> Okay how many register are rearraged in the new IP block. If there are
> large changes, consider using regmap_fields to abstract the register and
> bit differences..

Only one, config register. Regmap unfortunately is not an option here, because
how DMA peripheral works. Register values are actually stored in linked list
somewhere in RAM and when current DMA request is finished, DMA peripheral auto
loads next set of registers from memory.

>
> > Add support for it.
> >
> > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> > ---
> >
> > 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 6a37f8bb39b1..eceedd139651 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),
> > + .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;
> >
> > }
> >
> > /*