target/linux/bcm4908/patches-5.4/170-net-broadcom-bcm4908_enet-reset-DMA-rings-sw-indexes.patch

   1 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
   2 Date: Tue, 22 Jun 2021 07:05:04 +0200
   3 Subject: [PATCH] net: broadcom: bcm4908_enet: reset DMA rings sw indexes
   4  properly
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Resetting software indexes in bcm4908_dma_alloc_buf_descs() is not
  10 enough as it's called during device probe only. Driver resets DMA on
  11 every .ndo_open callback and it's required to reset indexes then.
  12
  13 This fixes inconsistent rings state and stalled traffic after interface
  14 down & up sequence.
  15
  16 Fixes: 4feffeadbcb2 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
  17 Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
  18 ---
  19  drivers/net/ethernet/broadcom/bcm4908_enet.c | 6 +++---
  20  1 file changed, 3 insertions(+), 3 deletions(-)
  21
  22 --- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
  23 +++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c
  24 @@ -174,9 +174,6 @@ static int bcm4908_dma_alloc_buf_descs(s
  25         if (!ring->slots)
  26                 goto err_free_buf_descs;
  27
  28 -       ring->read_idx = 0;
  29 -       ring->write_idx = 0;
  30 -
  31         return 0;
  32
  33  err_free_buf_descs:
  34 @@ -303,6 +300,9 @@ static void bcm4908_enet_dma_ring_init(s
  35
  36         enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_BASE_DESC_PTR,
  37                    (uint32_t)ring->dma_addr);
  38 +
  39 +       ring->read_idx = 0;
  40 +       ring->write_idx = 0;
  41  }
  42
  43  static void bcm4908_enet_dma_uninit(struct bcm4908_enet *enet)