target/linux/bcm27xx/patches-6.1/950-0916-dmaengine-bcm2835-Fix-dma-driver-for-BCM2835-38.patch

   1 From 75f44d1416c5de17865247d6d012c37f7650437c Mon Sep 17 00:00:00 2001
   2 From: Dom Cobley <popcornmix@gmail.com>
   3 Date: Wed, 24 May 2023 19:32:16 +0100
   4 Subject: [PATCH] dmaengine: bcm2835: Fix dma driver for BCM2835-38
   5
   6 The previous commit broke support on older devices.
   7 Make the breaking parts of patch conditional on
   8 the device being used.
   9
  10 Fixes: 6e1856ac7c39 ("dmaengine: bcm2835: HACK: Support DMA-Lite channels")
  11
  12 Signed-off-by: Dom Cobley <popcornmix@gmail.com>
  13 ---
  14  drivers/dma/bcm2835-dma.c | 17 +++++++++++++----
  15  1 file changed, 13 insertions(+), 4 deletions(-)
  16
  17 --- a/drivers/dma/bcm2835-dma.c
  18 +++ b/drivers/dma/bcm2835-dma.c
  19 @@ -102,6 +102,7 @@ struct bcm2835_chan {
  20
  21         bool is_lite_channel;
  22         bool is_40bit_channel;
  23 +       bool is_2712;
  24  };
  25
  26  struct bcm2835_desc {
  27 @@ -550,7 +551,11 @@ static struct bcm2835_desc *bcm2835_dma_
  28                         control_block->info = info;
  29                         control_block->src = src;
  30                         control_block->dst = dst;
  31 -                       control_block->stride = (upper_32_bits(dst) << 8) | upper_32_bits(src);
  32 +                       if (c->is_2712)
  33 +                               control_block->stride = (upper_32_bits(dst) << 8) |
  34 +                                                       upper_32_bits(src);
  35 +                       else
  36 +                               control_block->stride = 0;
  37                         control_block->next = 0;
  38                 }
  39
  40 @@ -575,7 +580,8 @@ static struct bcm2835_desc *bcm2835_dma_
  41                          d->cb_list[frame - 1].cb)->next_cb =
  42                                 to_40bit_cbaddr(cb_entry->paddr);
  43                 if (frame && !c->is_40bit_channel)
  44 -                       d->cb_list[frame - 1].cb->next = to_40bit_cbaddr(cb_entry->paddr);
  45 +                       d->cb_list[frame - 1].cb->next = c->is_2712 ?
  46 +                       to_40bit_cbaddr(cb_entry->paddr) : cb_entry->paddr;
  47
  48                 /* update src and dst and length */
  49                 if (src && (info & BCM2835_DMA_S_INC)) {
  50 @@ -762,7 +768,7 @@ static void bcm2835_dma_start_desc(struc
  51         } else {
  52                 writel(BIT(31), c->chan_base + BCM2835_DMA_CS);
  53
  54 -               writel(to_40bit_cbaddr(d->cb_list[0].paddr),
  55 +               writel(c->is_2712 ? to_40bit_cbaddr(d->cb_list[0].paddr) : d->cb_list[0].paddr,
  56                        c->chan_base + BCM2835_DMA_ADDR);
  57                 writel(BCM2835_DMA_ACTIVE | BCM2835_DMA_CS_FLAGS(c->dreq),
  58                        c->chan_base + BCM2835_DMA_CS);
  59 @@ -1132,7 +1138,8 @@ static struct dma_async_tx_descriptor *b
  60                  d->cb_list[frames - 1].cb)->next_cb =
  61                         to_40bit_cbaddr(d->cb_list[0].paddr);
  62         else
  63 -               d->cb_list[d->frames - 1].cb->next = to_40bit_cbaddr(d->cb_list[0].paddr);
  64 +               d->cb_list[d->frames - 1].cb->next = c->is_2712 ?
  65 +               to_40bit_cbaddr(d->cb_list[0].paddr) : d->cb_list[0].paddr;
  66
  67         return vchan_tx_prep(&c->vc, &d->vd, flags);
  68  }
  69 @@ -1199,6 +1206,8 @@ static int bcm2835_dma_chan_init(struct
  70         else if (readl(c->chan_base + BCM2835_DMA_DEBUG) &
  71                  BCM2835_DMA_DEBUG_LITE)
  72                 c->is_lite_channel = true;
  73 +       if (d->cfg_data->dma_mask == DMA_BIT_MASK(40))
  74 +               c->is_2712 = true;
  75
  76         return 0;
  77  }