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Diffstat (limited to 'target/linux/bcm27xx/patches-5.10/950-0334-net-bcmgenet-Reset-RBUF-on-first-open.patch')
-rw-r--r--target/linux/bcm27xx/patches-5.10/950-0334-net-bcmgenet-Reset-RBUF-on-first-open.patch70
1 files changed, 70 insertions, 0 deletions
diff --git a/target/linux/bcm27xx/patches-5.10/950-0334-net-bcmgenet-Reset-RBUF-on-first-open.patch b/target/linux/bcm27xx/patches-5.10/950-0334-net-bcmgenet-Reset-RBUF-on-first-open.patch
new file mode 100644
index 0000000000..7a6cc54f4c
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.10/950-0334-net-bcmgenet-Reset-RBUF-on-first-open.patch
@@ -0,0 +1,70 @@
+From eccfde35476213d30a67dedb63f007e7ae8da78c 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
+@@ -3244,7 +3244,7 @@ static void bcmgenet_get_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)
+ {
+ unsigned int i;
+ u32 reg;
+@@ -3269,6 +3269,14 @@ 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;
+ }
+
+@@ -3332,8 +3340,8 @@ static int bcmgenet_open(struct net_devi
+
+ bcmgenet_set_hw_addr(priv, dev->dev_addr);
+
+- /* 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);
+@@ -4187,7 +4195,7 @@ static int bcmgenet_resume(struct device
+ bcmgenet_hfb_create_rxnfc_filter(priv, rule);
+
+ /* 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);