On 06/05/2020 11:36, Amit Singh Tomar wrote:
Hi,
> DMA controller present on S700 SoC is compatible with the one on S900
> (as most of registers are same), but it has different DMA descriptor
> structure where registers "fcnt" and "ctrlb" uses different encoding.
>
> For instance, on S900 "fcnt" starts at offset 0x0c and uses upper 12
> bits whereas on S700, it starts at offset 0x1c and uses lower 12 bits.
>
> This commit adds support for DMA controller present on S700.
>
> Signed-off-by: Amit Singh Tomar <amittomer25@xxxxxxxxx>
> ---
> drivers/dma/owl-dma.c | 99 ++++++++++++++++++++++++++++++++++++---------------
> 1 file changed, 70 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/dma/owl-dma.c b/drivers/dma/owl-dma.c
> index b0d80a2fa383..6c2f0d0aad4c 100644
> --- a/drivers/dma/owl-dma.c
> +++ b/drivers/dma/owl-dma.c
> @@ -134,6 +134,11 @@ enum owl_dmadesc_offsets {
> OWL_DMADESC_SIZE
> };
>
> +enum owl_dma_id {
> + S900_DMA,
> + S700_DMA,
> +};
> +
> /**
> * struct owl_dma_lli - Link list for dma transfer
> * @hw: hardware link list
> @@ -200,6 +205,7 @@ struct owl_dma_vchan {
> * @pchans: array of data for the physical channels
> * @nr_vchans: the number of physical channels
> * @vchans: array of data for the physical channels
> + * @devid: device id based on OWL SoC
> */
> struct owl_dma {
> struct dma_device dma;
> @@ -214,6 +220,7 @@ struct owl_dma {
>
> unsigned int nr_vchans;
> struct owl_dma_vchan *vchans;
> + enum owl_dma_id devid;
> };
>
> static void pchan_update(struct owl_dma_pchan *pchan, u32 reg,
> @@ -354,6 +361,7 @@ static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan,
> struct dma_slave_config *sconfig,
> bool is_cyclic)
> {
> + struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
> u32 mode, ctrlb;
>
> mode = OWL_DMA_MODE_PW(0);
> @@ -409,8 +417,14 @@ static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan,
> lli->hw[OWL_DMADESC_DADDR] = dst;
> lli->hw[OWL_DMADESC_SRC_STRIDE] = 0;
> lli->hw[OWL_DMADESC_DST_STRIDE] = 0;
> - lli->hw[OWL_DMADESC_FLEN] = len | 1 << 20;
> - lli->hw[OWL_DMADESC_CTRLB] = ctrlb;
> +
> + if (od->devid == S700_DMA) {
> + lli->hw[OWL_DMADESC_FLEN] = len;
> + lli->hw[OWL_DMADESC_CTRLB] = 1 | ctrlb;
> + } else {
> + lli->hw[OWL_DMADESC_FLEN] = len | 1 << 20;
> + lli->hw[OWL_DMADESC_CTRLB] = ctrlb;
> + }
>
> return 0;
> }
> @@ -562,26 +576,35 @@ static irqreturn_t owl_dma_interrupt(int irq, void *dev_id)
> dma_writel(od, OWL_DMA_IRQ_PD0, pending);
>
> /* Check missed pending IRQ */
> - for (i = 0; i < od->nr_pchans; i++) {
> - pchan = &od->pchans[i];
> - chan_irq_pending = pchan_readl(pchan, OWL_DMAX_INT_CTL) &
> - pchan_readl(pchan, OWL_DMAX_INT_STATUS);
> -
> - /* Dummy read to ensure OWL_DMA_IRQ_PD0 value is updated */
> - dma_readl(od, OWL_DMA_IRQ_PD0);
> + if (od->devid == S900_DMA) {
You should mention (at least in the commit message) why this is needed.
And please move this into a separate function, this indentation is
becoming mad here.
> + for (i = 0; i < od->nr_pchans; i++) {
> + pchan = &od->pchans[i];
> + chan_irq_pending = pchan_readl(pchan,
> + OWL_DMAX_INT_CTL) &
> + pchan_readl(pchan,
> + OWL_DMAX_INT_STATUS)
> + ;
> +
> + /* Dummy read to ensure OWL_DMA_IRQ_PD0 value is
> + * updated
> + */
> + dma_readl(od, OWL_DMA_IRQ_PD0);
>
> - global_irq_pending = dma_readl(od, OWL_DMA_IRQ_PD0);
> + global_irq_pending = dma_readl(od,
> + OWL_DMA_IRQ_PD0);
>
> - if (chan_irq_pending && !(global_irq_pending & BIT(i))) {
> - dev_dbg(od->dma.dev,
> - "global and channel IRQ pending match err\n");
> + if (chan_irq_pending && !(global_irq_pending &
> + BIT(i))) {
> + dev_dbg(od->dma.dev,
> + "global and channel IRQ pending match err\n");
>
> - /* Clear IRQ status for this pchan */
> - pchan_update(pchan, OWL_DMAX_INT_STATUS,
> - 0xff, false);
> + /* Clear IRQ status for this pchan */
> + pchan_update(pchan, OWL_DMAX_INT_STATUS,
> + 0xff, false);
>
> - /* Update global IRQ pending */
> - pending |= BIT(i);
> + /* Update global IRQ pending */
> + pending |= BIT(i);
> + }
> }
> }
>
> @@ -720,6 +743,7 @@ static int owl_dma_resume(struct dma_chan *chan)
>
> static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan)
> {
> + struct owl_dma *od = to_owl_dma(vchan->vc.chan.device);
> struct owl_dma_pchan *pchan;
> struct owl_dma_txd *txd;
> struct owl_dma_lli *lli;
> @@ -741,9 +765,15 @@ static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan)
> list_for_each_entry(lli, &txd->lli_list, node) {
> /* Start from the next active node */
> if (lli->phys == next_lli_phy) {
> - list_for_each_entry(lli, &txd->lli_list, node)
> - bytes += lli->hw[OWL_DMADESC_FLEN] &
> - GENMASK(19, 0);
> + list_for_each_entry(lli, &txd->lli_list, node) {
> + if (od->devid == S700_DMA)
> + bytes +=
> + lli->hw[OWL_DMADESC_FLEN];
> + else
> + bytes +=
> + lli->hw[OWL_DMADESC_FLEN] &
> + GENMASK(19, 0);
You should have an accessor for getting the frame len, that should avoid
the insane wrapping here. Or factor this out into a helper function.
Alternatively revert the if statement and continue, that saves you one
level of indentation.
I guess flen is limited to 20 bits anyway, so you might want to apply
the 20-bit mask unconditionally.
Cheers,
Andre
> + }
> break;
> }
> }
> @@ -756,6 +786,7 @@ static enum dma_status owl_dma_tx_status(struct dma_chan *chan,
> dma_cookie_t cookie,
> struct dma_tx_state *state)
> {
> + struct owl_dma *od = to_owl_dma(chan->device);
> struct owl_dma_vchan *vchan = to_owl_vchan(chan);
> struct owl_dma_lli *lli;
> struct virt_dma_desc *vd;
> @@ -773,8 +804,13 @@ static enum dma_status owl_dma_tx_status(struct dma_chan *chan,
> vd = vchan_find_desc(&vchan->vc, cookie);
> if (vd) {
> txd = to_owl_txd(&vd->tx);
> - list_for_each_entry(lli, &txd->lli_list, node)
> - bytes += lli->hw[OWL_DMADESC_FLEN] & GENMASK(19, 0);
> + list_for_each_entry(lli, &txd->lli_list, node) {
> + if (od->devid == S700_DMA)
> + bytes += lli->hw[OWL_DMADESC_FLEN];
> + else
> + bytes += lli->hw[OWL_DMADESC_FLEN] &
> + GENMASK(19, 0);
> + }
> } else {
> bytes = owl_dma_getbytes_chan(vchan);
> }
> @@ -1031,11 +1067,20 @@ static struct dma_chan *owl_dma_of_xlate(struct of_phandle_args *dma_spec,
> return chan;
> }
>
> +static const struct of_device_id owl_dma_match[] = {
> + { .compatible = "actions,s900-dma", .data = (void *)S900_DMA,},
> + { .compatible = "actions,s700-dma", .data = (void *)S700_DMA,},
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, owl_dma_match);
> +
> static int owl_dma_probe(struct platform_device *pdev)
> {
> struct device_node *np = pdev->dev.of_node;
> struct owl_dma *od;
> int ret, i, nr_channels, nr_requests;
> + const struct of_device_id *of_id =
> + of_match_device(owl_dma_match, &pdev->dev);
>
> od = devm_kzalloc(&pdev->dev, sizeof(*od), GFP_KERNEL);
> if (!od)
> @@ -1060,6 +1105,8 @@ static int owl_dma_probe(struct platform_device *pdev)
> dev_info(&pdev->dev, "dma-channels %d, dma-requests %d\n",
> nr_channels, nr_requests);
>
> + od->devid = (enum owl_dma_id)of_id->data;
> +
> od->nr_pchans = nr_channels;
> od->nr_vchans = nr_requests;
>
> @@ -1192,12 +1239,6 @@ static int owl_dma_remove(struct platform_device *pdev)
> return 0;
> }
>
> -static const struct of_device_id owl_dma_match[] = {
> - { .compatible = "actions,s900-dma", },
> - { /* sentinel */ }
> -};
> -MODULE_DEVICE_TABLE(of, owl_dma_match);
> -
> static struct platform_driver owl_dma_driver = {
> .probe = owl_dma_probe,
> .remove = owl_dma_remove,
>
