From 7d3509774c2ef4ffd1c5fd2fac65dc4e071a6f21 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Wed, 30 Jun 2010 06:39:12 +0000 Subject: [PATCH] gianfar: Implement workaround for eTSEC74 erratum MPC8313ECE says: "If MACCFG2[Huge Frame]=0 and the Ethernet controller receives frames which are larger than MAXFRM, the controller truncates the frames to length MAXFRM and marks RxBD[TR]=1 to indicate the error. The controller also erroneously marks RxBD[TR]=1 if the received frame length is MAXFRM or MAXFRM-1, even though those frames are not truncated. No truncation or truncation error occurs if MACCFG2[Huge Frame]=1." There are two options to workaround the issue: "1. Set MACCFG2[Huge Frame]=1, so no truncation occurs for invalid large frames. Software can determine if a frame is larger than MAXFRM by reading RxBD[LG] or RxBD[Data Length]. 2. Set MAXFRM to 1538 (0x602) instead of the default 1536 (0x600), so normal-length frames are not marked as truncated. Software can examine RxBD[Data Length] to determine if the frame was larger than MAXFRM-2." This patch implements the first workaround option by setting HUGEFRAME bit, and gfar_clean_rx_ring() already checks the RxBD[Data Length]. Signed-off-by: Anton Vorontsov Signed-off-by: David S. Miller --- drivers/net/gianfar.c | 29 +++++++++++++++++++++++++++-- drivers/net/gianfar.h | 11 +++++++++++ 2 files changed, 38 insertions(+), 2 deletions(-) diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c index c52f3712ecd3..cee8ae714731 100644 --- a/drivers/net/gianfar.c +++ b/drivers/net/gianfar.c @@ -85,6 +85,7 @@ #include #include +#include #include #include #include @@ -928,6 +929,24 @@ static void gfar_init_filer_table(struct gfar_private *priv) } } +static void gfar_detect_errata(struct gfar_private *priv) +{ + struct device *dev = &priv->ofdev->dev; + unsigned int pvr = mfspr(SPRN_PVR); + unsigned int svr = mfspr(SPRN_SVR); + unsigned int mod = (svr >> 16) & 0xfff6; /* w/o E suffix */ + unsigned int rev = svr & 0xffff; + + /* MPC8313 Rev 2.0 and higher; All MPC837x */ + if ((pvr == 0x80850010 && mod == 0x80b0 && rev >= 0x0020) || + (pvr == 0x80861010 && (mod & 0xfff9) == 0x80c0)) + priv->errata |= GFAR_ERRATA_74; + + if (priv->errata) + dev_info(dev, "enabled errata workarounds, flags: 0x%x\n", + priv->errata); +} + /* Set up the ethernet device structure, private data, * and anything else we need before we start */ static int gfar_probe(struct of_device *ofdev, @@ -960,6 +979,8 @@ static int gfar_probe(struct of_device *ofdev, dev_set_drvdata(&ofdev->dev, priv); regs = priv->gfargrp[0].regs; + gfar_detect_errata(priv); + /* Stop the DMA engine now, in case it was running before */ /* (The firmware could have used it, and left it running). */ gfar_halt(dev); @@ -974,7 +995,10 @@ static int gfar_probe(struct of_device *ofdev, gfar_write(®s->maccfg1, tempval); /* Initialize MACCFG2. */ - gfar_write(®s->maccfg2, MACCFG2_INIT_SETTINGS); + tempval = MACCFG2_INIT_SETTINGS; + if (gfar_has_errata(priv, GFAR_ERRATA_74)) + tempval |= MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK; + gfar_write(®s->maccfg2, tempval); /* Initialize ECNTRL */ gfar_write(®s->ecntrl, ECNTRL_INIT_SETTINGS); @@ -2300,7 +2324,8 @@ static int gfar_change_mtu(struct net_device *dev, int new_mtu) * to allow huge frames, and to check the length */ tempval = gfar_read(®s->maccfg2); - if (priv->rx_buffer_size > DEFAULT_RX_BUFFER_SIZE) + if (priv->rx_buffer_size > DEFAULT_RX_BUFFER_SIZE || + gfar_has_errata(priv, GFAR_ERRATA_74)) tempval |= (MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK); else tempval &= ~(MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK); diff --git a/drivers/net/gianfar.h b/drivers/net/gianfar.h index ac4a92e08c09..0a0483ce21d2 100644 --- a/drivers/net/gianfar.h +++ b/drivers/net/gianfar.h @@ -1025,6 +1025,10 @@ struct gfar_priv_grp { char int_name_er[GFAR_INT_NAME_MAX]; }; +enum gfar_errata { + GFAR_ERRATA_74 = 0x01, +}; + /* Struct stolen almost completely (and shamelessly) from the FCC enet source * (Ok, that's not so true anymore, but there is a family resemblence) * The GFAR buffer descriptors track the ring buffers. The rx_bd_base @@ -1049,6 +1053,7 @@ struct gfar_private { struct device_node *node; struct net_device *ndev; struct of_device *ofdev; + enum gfar_errata errata; struct gfar_priv_grp gfargrp[MAXGROUPS]; struct gfar_priv_tx_q *tx_queue[MAX_TX_QS]; @@ -1111,6 +1116,12 @@ struct gfar_private { extern unsigned int ftp_rqfpr[MAX_FILER_IDX + 1]; extern unsigned int ftp_rqfcr[MAX_FILER_IDX + 1]; +static inline int gfar_has_errata(struct gfar_private *priv, + enum gfar_errata err) +{ + return priv->errata & err; +} + static inline u32 gfar_read(volatile unsigned __iomem *addr) { u32 val;