target/linux/bcm4908/patches-5.10/077-v5.14-net-broadcom-bcm4908_enet-reset-DMA-rings-sw-indexes.patch

   1 From ddeacc4f6494e07cbb6f033627926623f3e7a9d0 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
   3 Date: Tue, 22 Jun 2021 07:24:15 +0200
   4 Subject: [PATCH] net: broadcom: bcm4908_enet: reset DMA rings sw indexes
   5  properly
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 Resetting software indexes in bcm4908_dma_alloc_buf_descs() is not
  11 enough as it's called during device probe only. Driver resets DMA on
  12 every .ndo_open callback and it's required to reset indexes then.
  13
  14 This fixes inconsistent rings state and stalled traffic after interface
  15 down & up sequence.
  16
  17 Fixes: 4feffeadbcb2 ("net: broadcom: bcm4908enet: add BCM4908 controller driver")
  18 Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
  19 Signed-off-by: David S. Miller <davem@davemloft.net>
  20 ---
  21  drivers/net/ethernet/broadcom/bcm4908_enet.c | 6 +++---
  22  1 file changed, 3 insertions(+), 3 deletions(-)
  23
  24 --- a/drivers/net/ethernet/broadcom/bcm4908_enet.c
  25 +++ b/drivers/net/ethernet/broadcom/bcm4908_enet.c
  26 @@ -174,9 +174,6 @@ static int bcm4908_dma_alloc_buf_descs(s
  27         if (!ring->slots)
  28                 goto err_free_buf_descs;
  29
  30 -       ring->read_idx = 0;
  31 -       ring->write_idx = 0;
  32 -
  33         return 0;
  34
  35  err_free_buf_descs:
  36 @@ -303,6 +300,9 @@ static void bcm4908_enet_dma_ring_init(s
  37
  38         enet_write(enet, ring->st_ram_block + ENET_DMA_CH_STATE_RAM_BASE_DESC_PTR,
  39                    (uint32_t)ring->dma_addr);
  40 +
  41 +       ring->read_idx = 0;
  42 +       ring->write_idx = 0;
  43  }
  44
  45  static void bcm4908_enet_dma_uninit(struct bcm4908_enet *enet)