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net: bcmgenet: call bcmgenet_dma_teardown in bcmgenet_fini_dma 

We should not be manipulaging the DMA_CTRL registers directly by writing
0 to them to disable DMA. This is an operation that needs to be timed to
make sure the DMA engines have been properly stopped since their state
machine stops on a packet boundary, not immediately.

Make sure that tha bcmgenet_fini_dma() calls bcmgenet_dma_teardown() to
ensure a proper DMA engine state. As a result, we need to reorder the
function bodies to resolve the use dependency.

Fixes: 1c1008c793 ("net: bcmgenet: add main driver file")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hifive-unleashed-5.1
Florian Fainelli 2014-09-22 11:54:43 -07:00 committed by David S. Miller
parent 478a010c92
commit 4a0c081eff
1 changed files with 52 additions and 53 deletions
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105
drivers/net/ethernet/broadcom/genet/bcmgenet.c
View File

@ -1744,13 +1744,63 @@ static void bcmgenet_init_multiq(struct net_device *dev)
bcmgenet_tdma_writel(priv, reg, DMA_CTRL);
}
static int bcmgenet_dma_teardown(struct bcmgenet_priv *priv)
{
int ret = 0;
int timeout = 0;
u32 reg;
/* Disable TDMA to stop add more frames in TX DMA */
reg = bcmgenet_tdma_readl(priv, DMA_CTRL);
reg &= ~DMA_EN;
bcmgenet_tdma_writel(priv, reg, DMA_CTRL);
/* Check TDMA status register to confirm TDMA is disabled */
while (timeout++ < DMA_TIMEOUT_VAL) {
reg = bcmgenet_tdma_readl(priv, DMA_STATUS);
if (reg & DMA_DISABLED)
break;
udelay(1);
}
if (timeout == DMA_TIMEOUT_VAL) {
netdev_warn(priv->dev, "Timed out while disabling TX DMA\n");
ret = -ETIMEDOUT;
}
/* Wait 10ms for packet drain in both tx and rx dma */
usleep_range(10000, 20000);
/* Disable RDMA */
reg = bcmgenet_rdma_readl(priv, DMA_CTRL);
reg &= ~DMA_EN;
bcmgenet_rdma_writel(priv, reg, DMA_CTRL);
timeout = 0;
/* Check RDMA status register to confirm RDMA is disabled */
while (timeout++ < DMA_TIMEOUT_VAL) {
reg = bcmgenet_rdma_readl(priv, DMA_STATUS);
if (reg & DMA_DISABLED)
break;
udelay(1);
}
if (timeout == DMA_TIMEOUT_VAL) {
netdev_warn(priv->dev, "Timed out while disabling RX DMA\n");
ret = -ETIMEDOUT;
}
return ret;
}
static void bcmgenet_fini_dma(struct bcmgenet_priv *priv)
{
int i;
/* disable DMA */
bcmgenet_rdma_writel(priv, 0, DMA_CTRL);
bcmgenet_tdma_writel(priv, 0, DMA_CTRL);
bcmgenet_dma_teardown(priv);
for (i = 0; i < priv->num_tx_bds; i++) {
if (priv->tx_cbs[i].skb != NULL) {
@ -2109,57 +2159,6 @@ err_clk_disable:
return ret;
}
static int bcmgenet_dma_teardown(struct bcmgenet_priv *priv)
{
int ret = 0;
int timeout = 0;
u32 reg;
/* Disable TDMA to stop add more frames in TX DMA */
reg = bcmgenet_tdma_readl(priv, DMA_CTRL);
reg &= ~DMA_EN;
bcmgenet_tdma_writel(priv, reg, DMA_CTRL);
/* Check TDMA status register to confirm TDMA is disabled */
while (timeout++ < DMA_TIMEOUT_VAL) {
reg = bcmgenet_tdma_readl(priv, DMA_STATUS);
if (reg & DMA_DISABLED)
break;
udelay(1);
}
if (timeout == DMA_TIMEOUT_VAL) {
netdev_warn(priv->dev, "Timed out while disabling TX DMA\n");
ret = -ETIMEDOUT;
}
/* Wait 10ms for packet drain in both tx and rx dma */
usleep_range(10000, 20000);
/* Disable RDMA */
reg = bcmgenet_rdma_readl(priv, DMA_CTRL);
reg &= ~DMA_EN;
bcmgenet_rdma_writel(priv, reg, DMA_CTRL);
timeout = 0;
/* Check RDMA status register to confirm RDMA is disabled */
while (timeout++ < DMA_TIMEOUT_VAL) {
reg = bcmgenet_rdma_readl(priv, DMA_STATUS);
if (reg & DMA_DISABLED)
break;
udelay(1);
}
if (timeout == DMA_TIMEOUT_VAL) {
netdev_warn(priv->dev, "Timed out while disabling RX DMA\n");
ret = -ETIMEDOUT;
}
return ret;
}
static void bcmgenet_netif_stop(struct net_device *dev)
{
struct bcmgenet_priv *priv = netdev_priv(dev);