From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vipin Kumar Date: Fri, 1 Mar 2013 09:11:33 +0530 Subject: [U-Boot] [Drivers PATCH 14/19] net/macb: workaround for transmission hang issue In-Reply-To: <20130228135915.7f0e8426@lilith> References: <1c8cd3ce05a1064788a96bb4b49f9b82d9caf736.1351877124.git.vipin.kumar@st.com> <20130203121926.78fb7cda@lilith> <20130228135915.7f0e8426@lilith> Message-ID: <5130236D.3090900@st.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 2/28/2013 6:29 PM, Albert ARIBAUD wrote: > 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? > No, I have been busy with something. I would come back to the u-boot development soon Vipin > Amicalement,