target/linux/bcm27xx/patches-5.15/950-0274-bcm2835-dma-Advertise-the-full-DMA-range.patch

   1 From 775277f1d6585ea048c73ca001ed2867a32396a4 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.com>
   3 Date: Wed, 22 Jul 2020 17:59:31 +0100
   4 Subject: [PATCH] bcm2835-dma: Advertise the full DMA range
   5
   6 Unless the DMA mask is set wider than 32 bits, DMA mapping will use a
   7 bounce buffer.
   8
   9 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
  10 ---
  11  drivers/dma/bcm2835-dma.c | 18 +++++++++++++++---
  12  1 file changed, 15 insertions(+), 3 deletions(-)
  13
  14 --- a/drivers/dma/bcm2835-dma.c
  15 +++ b/drivers/dma/bcm2835-dma.c
  16 @@ -41,6 +41,7 @@
  17  #define BCM2711_DMA_MEMCPY_CHAN 14
  18
  19  struct bcm2835_dma_cfg_data {
  20 +       u64     dma_mask;
  21         u32     chan_40bit_mask;
  22  };
  23
  24 @@ -300,10 +301,12 @@ DEFINE_SPINLOCK(memcpy_lock);
  25
  26  static const struct bcm2835_dma_cfg_data bcm2835_dma_cfg = {
  27         .chan_40bit_mask = 0,
  28 +       .dma_mask = DMA_BIT_MASK(32),
  29  };
  30
  31  static const struct bcm2835_dma_cfg_data bcm2711_dma_cfg = {
  32         .chan_40bit_mask = BIT(11) | BIT(12) | BIT(13) | BIT(14),
  33 +       .dma_mask = DMA_BIT_MASK(36),
  34  };
  35
  36  static inline size_t bcm2835_dma_max_frame_length(struct bcm2835_chan *c)
  37 @@ -1180,6 +1183,8 @@ static struct dma_chan *bcm2835_dma_xlat
  38
  39  static int bcm2835_dma_probe(struct platform_device *pdev)
  40  {
  41 +       const struct bcm2835_dma_cfg_data *cfg_data;
  42 +       const struct of_device_id *of_id;
  43         struct bcm2835_dmadev *od;
  44         struct resource *res;
  45         void __iomem *base;
  46 @@ -1189,13 +1194,20 @@ static int bcm2835_dma_probe(struct plat
  47         int irq_flags;
  48         uint32_t chans_available;
  49         char chan_name[BCM2835_DMA_CHAN_NAME_SIZE];
  50 -       const struct of_device_id *of_id;
  51         int chan_count, chan_start, chan_end;
  52
  53 +       of_id = of_match_node(bcm2835_dma_of_match, pdev->dev.of_node);
  54 +       if (!of_id) {
  55 +               dev_err(&pdev->dev, "Failed to match compatible string\n");
  56 +               return -EINVAL;
  57 +       }
  58 +
  59 +       cfg_data = of_id->data;
  60 +
  61         if (!pdev->dev.dma_mask)
  62                 pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
  63
  64 -       rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
  65 +       rc = dma_set_mask_and_coherent(&pdev->dev, cfg_data->dma_mask);
  66         if (rc) {
  67                 dev_err(&pdev->dev, "Unable to set DMA mask\n");
  68                 return rc;
  69 @@ -1260,7 +1272,7 @@ static int bcm2835_dma_probe(struct plat
  70                 return -EINVAL;
  71         }
  72
  73 -       od->cfg_data = of_id->data;
  74 +       od->cfg_data = cfg_data;
  75
  76         /* Request DMA channel mask from device tree */
  77         if (of_property_read_u32(pdev->dev.of_node,