diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0973-net-bcmgenet-Reset-RBUF-on-first-open.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0973-net-bcmgenet-Reset-RBUF-on-first-open.patch | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0973-net-bcmgenet-Reset-RBUF-on-first-open.patch b/target/linux/bcm27xx/patches-5.4/950-0973-net-bcmgenet-Reset-RBUF-on-first-open.patch new file mode 100644 index 0000000000..b7f0ce0cad --- /dev/null +++ b/target/linux/bcm27xx/patches-5.4/950-0973-net-bcmgenet-Reset-RBUF-on-first-open.patch @@ -0,0 +1,70 @@ +From 507c4d749a1bbc3eb5c364dda61ac6bf95026cf1 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.com> +Date: Fri, 25 Sep 2020 15:07:23 +0100 +Subject: [PATCH] net: bcmgenet: Reset RBUF on first open + +If the RBUF logic is not reset when the kernel starts then there +may be some data left over from any network boot loader. If the +64-byte packet headers are enabled then this can be fatal. + +Extend bcmgenet_dma_disable to do perform the reset, but not when +called from bcmgenet_resume in order to preserve a wake packet. + +N.B. This different handling of resume is just based on a hunch - +why else wouldn't one reset the RBUF as well as the TBUF? If this +isn't the case then it's easy to change the patch to make the RBUF +reset unconditional. + +See: https://github.com/raspberrypi/linux/issues/3850 + +Signed-off-by: Phil Elwell <phil@raspberrypi.com> +--- + drivers/net/ethernet/broadcom/genet/bcmgenet.c | 16 ++++++++++++---- + 1 file changed, 12 insertions(+), 4 deletions(-) + +--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c ++++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c +@@ -2790,7 +2790,7 @@ static void bcmgenet_set_hw_addr(struct + } + + /* Returns a reusable dma control register value */ +-static u32 bcmgenet_dma_disable(struct bcmgenet_priv *priv) ++static u32 bcmgenet_dma_disable(struct bcmgenet_priv *priv, bool flush_rx) + { + u32 reg; + u32 dma_ctrl; +@@ -2809,6 +2809,14 @@ static u32 bcmgenet_dma_disable(struct b + udelay(10); + bcmgenet_umac_writel(priv, 0, UMAC_TX_FLUSH); + ++ if (flush_rx) { ++ reg = bcmgenet_rbuf_ctrl_get(priv); ++ bcmgenet_rbuf_ctrl_set(priv, reg | BIT(0)); ++ udelay(10); ++ bcmgenet_rbuf_ctrl_set(priv, reg); ++ udelay(10); ++ } ++ + return dma_ctrl; + } + +@@ -2910,8 +2918,8 @@ static int bcmgenet_open(struct net_devi + bcmgenet_ext_writel(priv, reg, EXT_EXT_PWR_MGMT); + } + +- /* Disable RX/TX DMA and flush TX queues */ +- dma_ctrl = bcmgenet_dma_disable(priv); ++ /* Disable RX/TX DMA and flush TX and RX queues */ ++ dma_ctrl = bcmgenet_dma_disable(priv, true); + + /* Reinitialize TDMA and RDMA and SW housekeeping */ + ret = bcmgenet_init_dma(priv); +@@ -3671,7 +3679,7 @@ static int bcmgenet_resume(struct device + bcmgenet_power_up(priv, GENET_POWER_WOL_MAGIC); + + /* Disable RX/TX DMA and flush TX queues */ +- dma_ctrl = bcmgenet_dma_disable(priv); ++ dma_ctrl = bcmgenet_dma_disable(priv, false); + + /* Reinitialize TDMA and RDMA and SW housekeeping */ + ret = bcmgenet_init_dma(priv); |