target/linux/layerscape/patches-5.4/701-net-0093-dpaa_eth-fix-iova-handling-for-contiguous-frames.patch

   1 From 39e4cf29431dec8aaad599d9734f7a0468a9c20b Mon Sep 17 00:00:00 2001
   2 From: Laurentiu Tudor <laurentiu.tudor@nxp.com>
   3 Date: Wed, 4 Apr 2018 12:31:05 +0300
   4 Subject: [PATCH] dpaa_eth: fix iova handling for contiguous frames
   5
   6 The driver relies on the no longer valid assumption that dma addresses
   7 (iovas) are identical to physical addressees and uses phys_to_virt() to
   8 make iova -> vaddr conversions. Fix this by adding a function that does
   9 proper iova -> phys conversions using the iommu api and update the code
  10 to use it.
  11 Also, a dma_unmap_single() call had to be moved further down the code
  12 because iova -> vaddr conversions were required before the unmap.
  13 For now only the contiguous frame case is handled and the SG case is
  14 split in a following patch.
  15 While at it, clean-up a redundant dpaa_bpid2pool() and pass the bp
  16 as parameter.
  17
  18 Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
  19 Acked-by: Madalin Bucur <madalin.bucur@nxp.com>
  20 ---
  21  drivers/net/ethernet/freescale/dpaa/dpaa_eth.c | 44 ++++++++++++++------------
  22  1 file changed, 24 insertions(+), 20 deletions(-)
  23
  24 --- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
  25 +++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
  26 @@ -50,6 +50,7 @@
  27  #include <linux/highmem.h>
  28  #include <linux/percpu.h>
  29  #include <linux/dma-mapping.h>
  30 +#include <linux/iommu.h>
  31  #include <linux/sort.h>
  32  #include <linux/phy_fixed.h>
  33  #include <soc/fsl/bman.h>
  34 @@ -1615,6 +1616,17 @@ static int dpaa_eth_refill_bpools(struct
  35         return 0;
  36  }
  37
  38 +static phys_addr_t dpaa_iova_to_phys(struct device *dev, dma_addr_t addr)
  39 +{
  40 +       struct iommu_domain *domain;
  41 +
  42 +       domain = iommu_get_domain_for_dev(dev);
  43 +       if (domain)
  44 +               return iommu_iova_to_phys(domain, addr);
  45 +       else
  46 +               return addr;
  47 +}
  48 +
  49  /* Cleanup function for outgoing frame descriptors that were built on Tx path,
  50   * either contiguous frames or scatter/gather ones.
  51   * Skb freeing is not handled here.
  52 @@ -1639,7 +1651,7 @@ static struct sk_buff *dpaa_cleanup_tx_f
  53         int nr_frags, i;
  54         u64 ns;
  55
  56 -       skbh = (struct sk_buff **)phys_to_virt(addr);
  57 +       skbh = (struct sk_buff **)phys_to_virt(dpaa_iova_to_phys(dev, addr));
  58         skb = *skbh;
  59
  60         if (unlikely(qm_fd_get_format(fd) == qm_fd_sg)) {
  61 @@ -1718,25 +1730,21 @@ static u8 rx_csum_offload(const struct d
  62   * accommodate the shared info area of the skb.
  63   */
  64  static struct sk_buff *contig_fd_to_skb(const struct dpaa_priv *priv,
  65 -                                       const struct qm_fd *fd)
  66 +                                       const struct qm_fd *fd,
  67 +                                       struct dpaa_bp *dpaa_bp,
  68 +                                       void *vaddr)
  69  {
  70         ssize_t fd_off = qm_fd_get_offset(fd);
  71 -       dma_addr_t addr = qm_fd_addr(fd);
  72 -       struct dpaa_bp *dpaa_bp;
  73         struct sk_buff *skb;
  74 -       void *vaddr;
  75
  76 -       vaddr = phys_to_virt(addr);
  77         WARN_ON(!IS_ALIGNED((unsigned long)vaddr, SMP_CACHE_BYTES));
  78
  79 -       dpaa_bp = dpaa_bpid2pool(fd->bpid);
  80 -       if (!dpaa_bp)
  81 -               goto free_buffer;
  82 -
  83         skb = build_skb(vaddr, dpaa_bp->size +
  84                         SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
  85 -       if (WARN_ONCE(!skb, "Build skb failure on Rx\n"))
  86 -               goto free_buffer;
  87 +       if (WARN_ONCE(!skb, "Build skb failure on Rx\n")) {
  88 +               skb_free_frag(vaddr);
  89 +               return NULL;
  90 +       }
  91         WARN_ON(fd_off != priv->rx_headroom);
  92         skb_reserve(skb, fd_off);
  93         skb_put(skb, qm_fd_get_length(fd));
  94 @@ -1744,10 +1752,6 @@ static struct sk_buff *contig_fd_to_skb(
  95         skb->ip_summed = rx_csum_offload(priv, fd);
  96
  97         return skb;
  98 -
  99 -free_buffer:
 100 -       skb_free_frag(vaddr);
 101 -       return NULL;
 102  }
 103
 104  /* Build an skb with the data of the first S/G entry in the linear portion and
 105 @@ -2476,12 +2480,12 @@ static enum qman_cb_dqrr_result rx_defau
 106         if (!dpaa_bp)
 107                 return qman_cb_dqrr_consume;
 108
 109 -       dma_unmap_single(dpaa_bp->dev, addr, dpaa_bp->size, DMA_FROM_DEVICE);
 110 -
 111         /* prefetch the first 64 bytes of the frame or the SGT start */
 112 -       vaddr = phys_to_virt(addr);
 113 +       vaddr = phys_to_virt(dpaa_iova_to_phys(dpaa_bp->dev, addr));
 114         prefetch(vaddr + qm_fd_get_offset(fd));
 115
 116 +       dma_unmap_single(dpaa_bp->dev, addr, dpaa_bp->size, DMA_FROM_DEVICE);
 117 +
 118         /* The only FD types that we may receive are contig and S/G */
 119         WARN_ON((fd_format != qm_fd_contig) && (fd_format != qm_fd_sg));
 120
 121 @@ -2492,7 +2496,7 @@ static enum qman_cb_dqrr_result rx_defau
 122         (*count_ptr)--;
 123
 124         if (likely(fd_format == qm_fd_contig))
 125 -               skb = contig_fd_to_skb(priv, fd);
 126 +               skb = contig_fd_to_skb(priv, fd, dpaa_bp, vaddr);
 127         else
 128                 skb = sg_fd_to_skb(priv, fd);
 129         if (!skb)