- bgmac_err(bgmac, "Unknown IRQs: 0x%08X\n", bgmac->int_status);
- bgmac->int_status = 0;
- }
-+ /* poll again if more events arrived in the mean time */
++ /* Poll again if more events arrived in the meantime */
+ if (bgmac_read(bgmac, BGMAC_INT_STATUS) & (BGMAC_IS_TX0 | BGMAC_IS_RX))
+ return handled;
Date: Sun, 12 Apr 2015 22:23:07 +0200
Subject: [PATCH] bgmac: simplify rx DMA error handling
-Unmap the DMA buffer before checking it. If it is poisoned, map it again
-and pass it back to the hardware.
+Unmap the DMA buffer before checking it. If an error occurs, free the
+buffer and allocate a new one. If allocation or mapping fails, retry as
+long as there is NAPI poll budget left (count every attempt instead of
+every frame).
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
-@@ -405,25 +405,20 @@ static int bgmac_dma_rx_read(struct bgma
+@@ -404,51 +404,33 @@ static int bgmac_dma_rx_read(struct bgma
+ void *buf = slot->buf;
u16 len, flags;
- /* Unmap buffer to make it accessible to the CPU */
+- /* Unmap buffer to make it accessible to the CPU */
- dma_sync_single_for_cpu(dma_dev, slot->dma_addr,
- BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE);
-+ dma_unmap_single(dma_dev, slot->dma_addr,
-+ BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE);
-
- /* Get info from the header */
- len = le16_to_cpu(rx->len);
- flags = le16_to_cpu(rx->flags);
+-
+- /* Get info from the header */
+- len = le16_to_cpu(rx->len);
+- flags = le16_to_cpu(rx->flags);
++ if (++handled >= weight - 1) /* Should never be greater */
++ break;
do {
- dma_addr_t old_dma_addr = slot->dma_addr;
- int err;
+- int err;
++ if (!slot->dma_addr)
++ break;
++
++ /* Unmap buffer to make it accessible to the CPU */
++ dma_unmap_single(dma_dev, slot->dma_addr,
++ BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE);
++ slot->dma_addr = 0;
++
++ /* Get info from the header */
++ len = le16_to_cpu(rx->len);
++ flags = le16_to_cpu(rx->flags);
/* Check for poison and drop or pass the packet */
if (len == 0xdead && flags == 0xbeef) {
- slot->dma_addr,
- BGMAC_RX_BUF_SIZE,
- DMA_FROM_DEVICE);
++ kfree(buf);
break;
}
-@@ -436,18 +431,8 @@ static int bgmac_dma_rx_read(struct bgma
- /* Poison the old skb */
- rx->len = cpu_to_le16(0xdead);
- rx->flags = cpu_to_le16(0xbeef);
+ /* Omit CRC. */
+ len -= ETH_FCS_LEN;
+
+- /* Prepare new skb as replacement */
+- err = bgmac_dma_rx_skb_for_slot(bgmac, slot);
+- if (err) {
+- /* Poison the old skb */
+- rx->len = cpu_to_le16(0xdead);
+- rx->flags = cpu_to_le16(0xbeef);
-
- dma_sync_single_for_device(dma_dev,
- slot->dma_addr,
- BGMAC_RX_BUF_SIZE,
- DMA_FROM_DEVICE);
- break;
- }
+- break;
+- }
- bgmac_dma_rx_setup_desc(bgmac, ring, ring->start);
-
- /* Unmap old skb, we'll pass it to the netfif */
- dma_unmap_single(dma_dev, old_dma_addr,
- BGMAC_RX_BUF_SIZE, DMA_FROM_DEVICE);
-
+-
skb = build_skb(buf, BGMAC_RX_ALLOC_SIZE);
skb_put(skb, BGMAC_RX_FRAME_OFFSET +
-@@ -461,6 +446,8 @@ static int bgmac_dma_rx_read(struct bgma
- handled++;
+ BGMAC_RX_BUF_OFFSET + len);
+@@ -458,14 +440,16 @@ static int bgmac_dma_rx_read(struct bgma
+ skb_checksum_none_assert(skb);
+ skb->protocol = eth_type_trans(skb, bgmac->net_dev);
+ napi_gro_receive(&bgmac->napi, skb);
+- handled++;
} while (0);
++ /* Prepare new skb as replacement */
++ if (bgmac_dma_rx_skb_for_slot(bgmac, slot))
++ continue;
++
+ bgmac_dma_rx_setup_desc(bgmac, ring, ring->start);
+
if (++ring->start >= BGMAC_RX_RING_SLOTS)
ring->start = 0;
+-
+- if (handled >= weight) /* Should never be greater */
+- break;
+ }
+ return handled;
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
-@@ -422,6 +422,14 @@ static int bgmac_dma_rx_read(struct bgma
+@@ -428,6 +428,13 @@ static int bgmac_dma_rx_read(struct bgma
break;
}
+ if (len > BGMAC_RX_ALLOC_SIZE) {
+ bgmac_err(bgmac, "Found oversized packet at slot %d, DMA issue!\n",
+ ring->start);
-+ rx->len = cpu_to_le16(0xdead);
-+ rx->flags = cpu_to_le16(0xbeef);
++ kfree(buf);
+ break;
+ }
+
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
-@@ -549,18 +549,26 @@ static void bgmac_dma_ring_desc_free(str
+@@ -545,18 +545,26 @@ static void bgmac_dma_ring_desc_free(str
ring->dma_base);
}
}
static int bgmac_dma_alloc(struct bgmac *bgmac)
-@@ -608,8 +616,6 @@ static int bgmac_dma_alloc(struct bgmac
+@@ -604,8 +612,6 @@ static int bgmac_dma_alloc(struct bgmac
}
for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
ring = &bgmac->rx_ring[i];
ring->num_slots = BGMAC_RX_RING_SLOTS;
ring->mmio_base = ring_base[i];
-@@ -632,15 +638,6 @@ static int bgmac_dma_alloc(struct bgmac
+@@ -628,15 +634,6 @@ static int bgmac_dma_alloc(struct bgmac
ring->index_base = lower_32_bits(ring->dma_base);
else
ring->index_base = 0;
}
return 0;
-@@ -650,10 +647,10 @@ err_dma_free:
+@@ -646,10 +643,10 @@ err_dma_free:
return -ENOMEM;
}
for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) {
ring = &bgmac->tx_ring[i];
-@@ -685,8 +682,13 @@ static void bgmac_dma_init(struct bgmac
+@@ -681,8 +678,13 @@ static void bgmac_dma_init(struct bgmac
if (ring->unaligned)
bgmac_dma_rx_enable(bgmac, ring);
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX,
ring->index_base +
-@@ -695,6 +697,8 @@ static void bgmac_dma_init(struct bgmac
+@@ -691,6 +693,8 @@ static void bgmac_dma_init(struct bgmac
ring->start = 0;
ring->end = 0;
}
}
/**************************************************
-@@ -1170,11 +1174,8 @@ static void bgmac_enable(struct bgmac *b
+@@ -1166,11 +1170,8 @@ static void bgmac_enable(struct bgmac *b
}
/* http://bcm-v4.sipsolutions.net/mac-gbit/gmac/chipinit */
/* 1 interrupt per received frame */
bgmac_write(bgmac, BGMAC_INT_RECV_LAZY, 1 << BGMAC_IRL_FC_SHIFT);
-@@ -1192,16 +1193,7 @@ static void bgmac_chip_init(struct bgmac
+@@ -1188,16 +1189,7 @@ static void bgmac_chip_init(struct bgmac
bgmac_write(bgmac, BGMAC_RXMAX_LENGTH, 32 + ETHER_MAX_LEN);
bgmac_enable(bgmac);
}
-@@ -1261,8 +1253,15 @@ static int bgmac_open(struct net_device
+@@ -1257,8 +1249,13 @@ static int bgmac_open(struct net_device
int err = 0;
bgmac_chip_reset(bgmac);
+
+ err = bgmac_dma_init(bgmac);
-+ if (err) {
-+ bgmac_dma_cleanup(bgmac);
-+ return err;
-+ }
++ if (err)
++ goto err_out;
+
/* Specs say about reclaiming rings here, but we do that in DMA init */
- bgmac_chip_init(bgmac, true);
err = request_irq(bgmac->core->irq, bgmac_interrupt, IRQF_SHARED,
KBUILD_MODNAME, net_dev);
-@@ -1293,6 +1292,7 @@ static int bgmac_stop(struct net_device
+@@ -1273,6 +1270,7 @@ static int bgmac_open(struct net_device
+ netif_carrier_on(net_dev);
+
+ err_out:
++ bgmac_dma_cleanup(bgmac);
+ return err;
+ }
+
+@@ -1289,6 +1287,7 @@ static int bgmac_stop(struct net_device
free_irq(bgmac->core->irq, net_dev);
bgmac_chip_reset(bgmac);
struct device *dma_dev = bgmac->core->dma_dev;
struct bgmac_slot_info *slot = &ring->slots[ring->start];
struct bgmac_rx_header *rx = slot->buf + BGMAC_RX_BUF_OFFSET;
-@@ -463,6 +473,8 @@ static int bgmac_dma_rx_read(struct bgma
- break;
+@@ -459,6 +469,8 @@ static int bgmac_dma_rx_read(struct bgma
+ ring->start = 0;
}
+ bgmac_dma_rx_update_index(bgmac, ring);
return handled;
}
-@@ -682,6 +694,8 @@ static int bgmac_dma_init(struct bgmac *
+@@ -678,6 +690,8 @@ static int bgmac_dma_init(struct bgmac *
if (ring->unaligned)
bgmac_dma_rx_enable(bgmac, ring);
for (j = 0; j < ring->num_slots; j++) {
err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]);
if (err)
-@@ -690,12 +704,7 @@ static int bgmac_dma_init(struct bgmac *
+@@ -686,12 +700,7 @@ static int bgmac_dma_init(struct bgmac *
bgmac_dma_rx_setup_desc(bgmac, ring, j);
}
ctl0 |= BGMAC_DESC_CTL0_EOT;
ctl1 |= BGMAC_RX_BUF_SIZE & BGMAC_DESC_CTL1_LEN;
/* Is there any BGMAC device that requires extension? */
-@@ -508,7 +508,7 @@ static void bgmac_dma_tx_ring_free(struc
+@@ -504,7 +504,7 @@ static void bgmac_dma_tx_ring_free(struc
struct bgmac_slot_info *slot;
int i;
int len = dma_desc[i].ctl1 & BGMAC_DESC_CTL1_LEN;
slot = &ring->slots[i];
-@@ -533,7 +533,7 @@ static void bgmac_dma_rx_ring_free(struc
+@@ -529,7 +529,7 @@ static void bgmac_dma_rx_ring_free(struc
struct bgmac_slot_info *slot;
int i;
slot = &ring->slots[i];
if (!slot->buf)
continue;
-@@ -547,7 +547,8 @@ static void bgmac_dma_rx_ring_free(struc
+@@ -543,7 +543,8 @@ static void bgmac_dma_rx_ring_free(struc
}
static void bgmac_dma_ring_desc_free(struct bgmac *bgmac,
{
struct device *dma_dev = bgmac->core->dma_dev;
int size;
-@@ -556,7 +557,7 @@ static void bgmac_dma_ring_desc_free(str
+@@ -552,7 +553,7 @@ static void bgmac_dma_ring_desc_free(str
return;
/* Free ring of descriptors */
dma_free_coherent(dma_dev, size, ring->cpu_base,
ring->dma_base);
}
-@@ -577,10 +578,12 @@ static void bgmac_dma_free(struct bgmac
+@@ -573,10 +574,12 @@ static void bgmac_dma_free(struct bgmac
int i;
for (i = 0; i < BGMAC_MAX_TX_RINGS; i++)
}
static int bgmac_dma_alloc(struct bgmac *bgmac)
-@@ -603,11 +606,10 @@ static int bgmac_dma_alloc(struct bgmac
+@@ -599,11 +602,10 @@ static int bgmac_dma_alloc(struct bgmac
for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) {
ring = &bgmac->tx_ring[i];
ring->cpu_base = dma_zalloc_coherent(dma_dev, size,
&ring->dma_base,
GFP_KERNEL);
-@@ -629,11 +631,10 @@ static int bgmac_dma_alloc(struct bgmac
+@@ -625,11 +627,10 @@ static int bgmac_dma_alloc(struct bgmac
for (i = 0; i < BGMAC_MAX_RX_RINGS; i++) {
ring = &bgmac->rx_ring[i];
ring->cpu_base = dma_zalloc_coherent(dma_dev, size,
&ring->dma_base,
GFP_KERNEL);
-@@ -696,7 +697,7 @@ static int bgmac_dma_init(struct bgmac *
+@@ -692,7 +693,7 @@ static int bgmac_dma_init(struct bgmac *
ring->start = 0;
ring->end = 0;
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
-@@ -1609,8 +1609,11 @@ static int bgmac_probe(struct bcma_devic
+@@ -1604,8 +1604,11 @@ static int bgmac_probe(struct bcma_devic
ns_core = bcma_find_core_unit(core->bus,
BCMA_CORE_MAC_GBIT,
ns_gmac);
#include <bcm47xx_nvram.h>
static const struct bcma_device_id bgmac_bcma_tbl[] = {
-@@ -1524,6 +1525,17 @@ static void bgmac_mii_unregister(struct
+@@ -1519,6 +1520,17 @@ static void bgmac_mii_unregister(struct
mdiobus_free(mii_bus);
}
/**************************************************
* BCMA bus ops
**************************************************/
-@@ -1650,6 +1662,16 @@ static int bgmac_probe(struct bcma_devic
+@@ -1645,6 +1657,16 @@ static int bgmac_probe(struct bcma_devic
net_dev->hw_features = net_dev->features;
net_dev->vlan_features = net_dev->features;
err = register_netdev(bgmac->net_dev);
if (err) {
bgmac_err(bgmac, "Cannot register net device\n");
-@@ -1676,6 +1698,10 @@ static void bgmac_remove(struct bcma_dev
+@@ -1671,6 +1693,10 @@ static void bgmac_remove(struct bcma_dev
{
struct bgmac *bgmac = bcma_get_drvdata(core);