From 14870b75fe0be5c565339f008ba25326f86a7ce8 Mon Sep 17 00:00:00 2001 From: Esben Haabendal Date: Thu, 17 Jun 2021 11:49:28 +0200 Subject: [PATCH] net: gianfar: Implement rx_missed_errors counter Devices with RMON support has a 16-bit RDRP counter. It provides: "Receive dropped packets counter. Increments for frames received which are streamed to system but are later dropped due to lack of system resources." To handle more than 2^16 dropped packets, a carry bit in CAR1 register is set on overflow, so we enable irq when this is set, extending the counter to 2^64 for handling situations where lots of packets are missed (e.g. during heavy network storms). Signed-off-by: Esben Haabendal Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/gianfar.c | 50 ++++++++++++++++++++++++++++++-- drivers/net/ethernet/freescale/gianfar.h | 10 +++++++ 2 files changed, 57 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c index 4608c0c..9646483 100644 --- a/drivers/net/ethernet/freescale/gianfar.c +++ b/drivers/net/ethernet/freescale/gianfar.c @@ -289,6 +289,29 @@ static void gfar_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *s stats->tx_bytes += priv->tx_queue[i]->stats.tx_bytes; stats->tx_packets += priv->tx_queue[i]->stats.tx_packets; } + + if (priv->device_flags & FSL_GIANFAR_DEV_HAS_RMON) { + struct rmon_mib __iomem *rmon = &priv->gfargrp[0].regs->rmon; + unsigned long flags; + u32 rdrp, car, car_before; + u64 rdrp_offset; + + spin_lock_irqsave(&priv->rmon_overflow.lock, flags); + car = gfar_read(&rmon->car1) & CAR1_C1RDR; + do { + car_before = car; + rdrp = gfar_read(&rmon->rdrp); + car = gfar_read(&rmon->car1) & CAR1_C1RDR; + } while (car != car_before); + if (car) { + priv->rmon_overflow.rdrp++; + gfar_write(&rmon->car1, car); + } + rdrp_offset = priv->rmon_overflow.rdrp; + spin_unlock_irqrestore(&priv->rmon_overflow.lock, flags); + + stats->rx_missed_errors = rdrp + (rdrp_offset << 16); + } } /* Set the appropriate hash bit for the given addr */ @@ -379,7 +402,8 @@ static void gfar_ints_enable(struct gfar_private *priv) for (i = 0; i < priv->num_grps; i++) { struct gfar __iomem *regs = priv->gfargrp[i].regs; /* Unmask the interrupts we look for */ - gfar_write(®s->imask, IMASK_DEFAULT); + gfar_write(®s->imask, + IMASK_DEFAULT | priv->rmon_overflow.imask); } } @@ -2287,7 +2311,7 @@ static irqreturn_t gfar_receive(int irq, void *grp_id) if (likely(napi_schedule_prep(&grp->napi_rx))) { spin_lock_irqsave(&grp->grplock, flags); imask = gfar_read(&grp->regs->imask); - imask &= IMASK_RX_DISABLED; + imask &= IMASK_RX_DISABLED | grp->priv->rmon_overflow.imask; gfar_write(&grp->regs->imask, imask); spin_unlock_irqrestore(&grp->grplock, flags); __napi_schedule(&grp->napi_rx); @@ -2311,7 +2335,7 @@ static irqreturn_t gfar_transmit(int irq, void *grp_id) if (likely(napi_schedule_prep(&grp->napi_tx))) { spin_lock_irqsave(&grp->grplock, flags); imask = gfar_read(&grp->regs->imask); - imask &= IMASK_TX_DISABLED; + imask &= IMASK_TX_DISABLED | grp->priv->rmon_overflow.imask; gfar_write(&grp->regs->imask, imask); spin_unlock_irqrestore(&grp->grplock, flags); __napi_schedule(&grp->napi_tx); @@ -2682,6 +2706,18 @@ static irqreturn_t gfar_error(int irq, void *grp_id) } netif_dbg(priv, tx_err, dev, "Transmit Error\n"); } + if (events & IEVENT_MSRO) { + struct rmon_mib __iomem *rmon = ®s->rmon; + u32 car; + + spin_lock(&priv->rmon_overflow.lock); + car = gfar_read(&rmon->car1) & CAR1_C1RDR; + if (car) { + priv->rmon_overflow.rdrp++; + gfar_write(&rmon->car1, car); + } + spin_unlock(&priv->rmon_overflow.lock); + } if (events & IEVENT_BSY) { dev->stats.rx_over_errors++; atomic64_inc(&priv->extra_stats.rx_bsy); @@ -3259,6 +3295,14 @@ static int gfar_probe(struct platform_device *ofdev) gfar_hw_init(priv); + if (priv->device_flags & FSL_GIANFAR_DEV_HAS_RMON) { + struct rmon_mib __iomem *rmon = &priv->gfargrp[0].regs->rmon; + + spin_lock_init(&priv->rmon_overflow.lock); + priv->rmon_overflow.imask = IMASK_MSRO; + gfar_write(&rmon->cam1, gfar_read(&rmon->cam1) & ~CAM1_M1RDR); + } + /* Carrier starts down, phylib will bring it up */ netif_carrier_off(dev); diff --git a/drivers/net/ethernet/freescale/gianfar.h b/drivers/net/ethernet/freescale/gianfar.h index c8aa140..ca5e14f 100644 --- a/drivers/net/ethernet/freescale/gianfar.h +++ b/drivers/net/ethernet/freescale/gianfar.h @@ -663,6 +663,15 @@ struct rmon_mib u32 cam2; /* 0x.73c - Carry Mask Register Two */ }; +struct rmon_overflow { + /* lock for synchronization of the rdrp field of this struct, and + * CAR1/CAR2 registers + */ + spinlock_t lock; + u32 imask; + u64 rdrp; +}; + struct gfar_extra_stats { atomic64_t rx_alloc_err; atomic64_t rx_large; @@ -1150,6 +1159,7 @@ struct gfar_private { /* Network Statistics */ struct gfar_extra_stats extra_stats; + struct rmon_overflow rmon_overflow; /* PHY stuff */ phy_interface_t interface; -- 2.7.4