target/linux/brcm2708/patches-4.4/0388-Revert-bcm2835-dma-Fix-up-convert-to-DMA-pool.patch

   1 From 80e7256b69b395f91738b44dc259c9fa4d15dda3 Mon Sep 17 00:00:00 2001
   2 From: Martin Sperl <kernel@martin.sperl.org>
   3 Date: Fri, 22 Apr 2016 17:17:13 +0000
   4 Subject: [PATCH] Revert "bcm2835-dma: Fix up convert to DMA pool"
   5
   6 This reverts commit ec2e48fda22c57cab56a4332d1a095f91c919493.
   7 ---
   8  drivers/dma/bcm2835-dma.c | 36 ++++++++++--------------------------
   9  1 file changed, 10 insertions(+), 26 deletions(-)
  10
  11 --- a/drivers/dma/bcm2835-dma.c
  12 +++ b/drivers/dma/bcm2835-dma.c
  13 @@ -488,17 +488,6 @@ static struct dma_async_tx_descriptor *b
  14         c->cyclic = true;
  15
  16         return vchan_tx_prep(&c->vc, &d->vd, flags);
  17 -error_cb:
  18 -       i--;
  19 -       for (; i >= 0; i--) {
  20 -               struct bcm2835_cb_entry *cb_entry = &d->cb_list[i];
  21 -
  22 -               dma_pool_free(c->cb_pool, cb_entry->cb, cb_entry->paddr);
  23 -       }
  24 -
  25 -       kfree(d->cb_list);
  26 -       kfree(d);
  27 -       return NULL;
  28  }
  29
  30  static struct dma_async_tx_descriptor *
  31 @@ -545,7 +534,6 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  32         if (!d)
  33                 return NULL;
  34
  35 -       d->c = c;
  36         d->dir = direction;
  37
  38         if (c->ch >= 8) /* LITE channel */
  39 @@ -565,21 +553,15 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  40                 d->frames += len / max_size + 1;
  41         }
  42
  43 -       d->cb_list = kcalloc(d->frames, sizeof(*d->cb_list), GFP_KERNEL);
  44 -       if (!d->cb_list) {
  45 +       /* Allocate memory for control blocks */
  46 +       d->control_block_size = d->frames * sizeof(struct bcm2835_dma_cb);
  47 +       d->control_block_base = dma_zalloc_coherent(chan->device->dev,
  48 +                       d->control_block_size, &d->control_block_base_phys,
  49 +                       GFP_NOWAIT);
  50 +       if (!d->control_block_base) {
  51                 kfree(d);
  52                 return NULL;
  53         }
  54 -       /* Allocate memory for control blocks */
  55 -       for (i = 0; i < d->frames; i++) {
  56 -               struct bcm2835_cb_entry *cb_entry = &d->cb_list[i];
  57 -
  58 -               cb_entry->cb = dma_pool_zalloc(c->cb_pool, GFP_ATOMIC,
  59 -                                               &cb_entry->paddr);
  60 -
  61 -               if (!cb_entry->cb)
  62 -                       goto error_cb;
  63 -       }
  64
  65         /*
  66          * Iterate over all SG entries, create a control block
  67 @@ -596,7 +578,7 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  68
  69                 for (j = 0; j < len; j += max_size) {
  70                         struct bcm2835_dma_cb *control_block =
  71 -                               d->cb_list[i + split_cnt].cb;
  72 +                               &d->control_block_base[i + split_cnt];
  73
  74                         /* Setup addresses */
  75                         if (d->dir == DMA_DEV_TO_MEM) {
  76 @@ -638,7 +620,9 @@ bcm2835_dma_prep_slave_sg(struct dma_cha
  77                         if (i < sg_len - 1 || len - j > max_size) {
  78                                 /* Next block is the next frame. */
  79                                 control_block->next =
  80 -                                       d->cb_list[i + split_cnt + 1].paddr;
  81 +                                       d->control_block_base_phys +
  82 +                                       sizeof(struct bcm2835_dma_cb) *
  83 +                                       (i + split_cnt + 1);
  84                         } else {
  85                                 /* Next block is empty. */
  86                                 control_block->next = 0;