From mboxrd@z Thu Jan 1 00:00:00 1970 From: Albert ARIBAUD Date: Thu, 28 Feb 2013 13:59:15 +0100 Subject: [U-Boot] [Drivers PATCH 14/19] net/macb: workaround for transmission hang issue In-Reply-To: <20130203121926.78fb7cda@lilith> References: <1c8cd3ce05a1064788a96bb4b49f9b82d9caf736.1351877124.git.vipin.kumar@st.com> <20130203121926.78fb7cda@lilith> Message-ID: <20130228135915.7f0e8426@lilith> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Sun, 3 Feb 2013 12:19:26 +0100, Albert ARIBAUD wrote: > Hi Vipin, > > On Fri, 2 Nov 2012 23:09:59 +0530, Vipin Kumar > wrote: > > > From: Shiraz Hashim > > > > 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 > > --- > > 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) > > This patch did not reappear in later versions of the series, and no > other standalone patch seems to match it. Was it dropped? Ping? Amicalement, -- Albert.