From: Shiraz Hashim shiraz.hashim@st.com
It is observed on SPEAr320S RMII#1 interface that on transmitting packets the MAC dma hangs randomly and constantly showing busy tx-go state.
It comes out if this situation only when Transmission is disabled and enabled again.
Since it happens randomly and u-boot doesn't require high performance we disable TE and re-enable it on each transmission. We also change number of transmit descriptor to 1 as we would not require more than it, further it would not alter GMAC notion of transmit descriptor start queue as it always point to same descriptor.
Signed-off-by: Shiraz Hashim shiraz.hashim@st.com --- drivers/net/macb.c | 38 ++++++++++++++++++++++++++++++++++---- 1 file changed, 34 insertions(+), 4 deletions(-)
diff --git a/drivers/net/macb.c b/drivers/net/macb.c index ac25b52..17bad33 100644 --- a/drivers/net/macb.c +++ b/drivers/net/macb.c @@ -55,7 +55,7 @@
#define CONFIG_SYS_MACB_RX_BUFFER_SIZE 4096 #define CONFIG_SYS_MACB_RX_RING_SIZE (CONFIG_SYS_MACB_RX_BUFFER_SIZE / 128) -#define CONFIG_SYS_MACB_TX_RING_SIZE 16 +#define CONFIG_SYS_MACB_TX_RING_SIZE 1 #define CONFIG_SYS_MACB_TX_TIMEOUT 1000 #define CONFIG_SYS_MACB_AUTONEG_TIMEOUT 5000000
@@ -226,7 +226,13 @@ static int macb_send(struct eth_device *netdev, void *packet, int length) macb->tx_ring[tx_head].ctrl = ctrl; macb->tx_ring[tx_head].addr = paddr; barrier(); - macb_writel(macb, NCR, MACB_BIT(TE) | MACB_BIT(RE) | MACB_BIT(TSTART)); + /* + * Due to issues on SPEAr320 RMII, disable TE first so that + * controller can come out if it is hanged during transmission + */ + macb_writel(macb, NCR, macb_readl(macb, NCR) & ~MACB_BIT(TE)); + macb_writel(macb, NCR, macb_readl(macb, NCR) | + MACB_BIT(TE) | MACB_BIT(TSTART));
/* * I guess this is necessary because the networking core may @@ -444,6 +450,31 @@ static int macb_phy_init(struct macb_device *macb) } }
+static void macb_reset_hw(struct macb_device *bp) +{ + /* Make sure we have the write buffer for ourselves */ + barrier(); + /* + * Disable RX and TX (XXX: Should we halt the transmission + * more gracefully?) and we should not close the mdio port + */ + macb_writel(bp, NCR, 0); + + /* Clear the stats registers (XXX: Update stats first?) */ + macb_writel(bp, NCR, MACB_BIT(CLRSTAT)); + + /* keep the mdio port , otherwise other eth will not work */ + macb_writel(bp, NCR, MACB_BIT(MPE)); + + /* Clear all status flags */ + macb_writel(bp, TSR, ~0UL); + macb_writel(bp, RSR, ~0UL); + + /* Disable all interrupts */ + macb_writel(bp, IDR, ~0UL); + macb_readl(bp, ISR); +} + static int macb_init(struct eth_device *netdev, bd_t *bd) { struct macb_device *macb = to_macb(netdev); @@ -520,8 +551,7 @@ static void macb_halt(struct eth_device *netdev) tsr = macb_readl(macb, TSR); } while (tsr & MACB_BIT(TGO));
- /* Disable TX and RX, and clear statistics */ - macb_writel(macb, NCR, MACB_BIT(CLRSTAT)); + macb_reset_hw(macb); }
static int macb_write_hwaddr(struct eth_device *dev)