net: bcmgenet: Reset RBUF on first open
[ Upstream commit 0a6380cb4c6b5c1d6dad226ba3130f9090f0ccea ]
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
See: https://github.com/raspberrypi/firmware/issues/1882
Signed-off-by: Phil Elwell <phil@raspberrypi.com>
Signed-off-by: Maarten Vanraes <maarten@rmail.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 510e7b18fdad4b55849d7a73b8ff2c3e8ad2f7af)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 445e892..da240c5 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -2805,7 +2805,7 @@
}
/* 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;
@@ -2830,6 +2830,14 @@
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;
}
@@ -2931,8 +2939,8 @@
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);
@@ -3729,7 +3737,7 @@
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);