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brcm47xx: bgmac: implement unaligned addressing for DMA rings that support it

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This is important patch for new devices that support unaligned
addressing. That devices suffer from the backward-compatibility bug in
DMA engine. In theory we should be able to use old mechanism, but in
practice DMA address seems to be randomly copied into status register
when hardware reaches end of a ring. This breaks reading slot number
from status register and we can't use DMA anymore.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>

SVN-Revision: 38004
This commit is contained in:
Hauke Mehrtens 2013-09-16 19:46:34 +00:00
parent a0d6cd4f49
commit f687ab2101
2 changed files with 146 additions and 6 deletions
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140
target/linux/brcm47xx/patches-3.10/712-bgmac_implement_unaligned_addressing.patch Normal file
View file

@ -0,0 +1,140 @@
bgmac: implement unaligned addressing for DMA rings that support it
This is important patch for new devices that support unaligned
addressing. That devices suffer from the backward-compatibility bug in
DMA engine. In theory we should be able to use old mechanism, but in
practice DMA address seems to be randomly copied into status register
when hardware reaches end of a ring. This breaks reading slot number
from status register and we can't use DMA anymore.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -157,6 +157,7 @@ static netdev_tx_t bgmac_dma_tx_add(stru
if (++ring->end >= BGMAC_TX_RING_SLOTS)
ring->end = 0;
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_INDEX,
+ ring->index_base +
ring->end * sizeof(struct bgmac_dma_desc));
/* Always keep one slot free to allow detecting bugged calls. */
@@ -181,6 +182,8 @@ static void bgmac_dma_tx_free(struct bgm
/* The last slot that hardware didn't consume yet */
empty_slot = bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_TX_STATUS);
empty_slot &= BGMAC_DMA_TX_STATDPTR;
+ empty_slot -= ring->index_base;
+ empty_slot &= BGMAC_DMA_TX_STATDPTR;
empty_slot /= sizeof(struct bgmac_dma_desc);
while (ring->start != empty_slot) {
@@ -274,6 +277,8 @@ static int bgmac_dma_rx_read(struct bgma
end_slot = bgmac_read(bgmac, ring->mmio_base + BGMAC_DMA_RX_STATUS);
end_slot &= BGMAC_DMA_RX_STATDPTR;
+ end_slot -= ring->index_base;
+ end_slot &= BGMAC_DMA_RX_STATDPTR;
end_slot /= sizeof(struct bgmac_dma_desc);
ring->end = end_slot;
@@ -418,9 +423,6 @@ static int bgmac_dma_alloc(struct bgmac
ring = &bgmac->tx_ring[i];
ring->num_slots = BGMAC_TX_RING_SLOTS;
ring->mmio_base = ring_base[i];
- if (bgmac_dma_unaligned(bgmac, ring, BGMAC_DMA_RING_TX))
- bgmac_warn(bgmac, "TX on ring 0x%X supports unaligned addressing but this feature is not implemented\n",
- ring->mmio_base);
/* Alloc ring of descriptors */
size = ring->num_slots * sizeof(struct bgmac_dma_desc);
@@ -435,6 +437,13 @@ static int bgmac_dma_alloc(struct bgmac
if (ring->dma_base & 0xC0000000)
bgmac_warn(bgmac, "DMA address using 0xC0000000 bit(s), it may need translation trick\n");
+ ring->unaligned = bgmac_dma_unaligned(bgmac, ring,
+ BGMAC_DMA_RING_TX);
+ if (ring->unaligned)
+ ring->index_base = lower_32_bits(ring->dma_base);
+ else
+ ring->index_base = 0;
+
/* No need to alloc TX slots yet */
}
@@ -444,9 +453,6 @@ static int bgmac_dma_alloc(struct bgmac
ring = &bgmac->rx_ring[i];
ring->num_slots = BGMAC_RX_RING_SLOTS;
ring->mmio_base = ring_base[i];
- if (bgmac_dma_unaligned(bgmac, ring, BGMAC_DMA_RING_RX))
- bgmac_warn(bgmac, "RX on ring 0x%X supports unaligned addressing but this feature is not implemented\n",
- ring->mmio_base);
/* Alloc ring of descriptors */
size = ring->num_slots * sizeof(struct bgmac_dma_desc);
@@ -462,6 +468,13 @@ static int bgmac_dma_alloc(struct bgmac
if (ring->dma_base & 0xC0000000)
bgmac_warn(bgmac, "DMA address using 0xC0000000 bit(s), it may need translation trick\n");
+ ring->unaligned = bgmac_dma_unaligned(bgmac, ring,
+ BGMAC_DMA_RING_RX);
+ if (ring->unaligned)
+ ring->index_base = lower_32_bits(ring->dma_base);
+ else
+ ring->index_base = 0;
+
/* Alloc RX slots */
for (j = 0; j < ring->num_slots; j++) {
err = bgmac_dma_rx_skb_for_slot(bgmac, &ring->slots[j]);
@@ -489,12 +502,14 @@ static void bgmac_dma_init(struct bgmac
for (i = 0; i < BGMAC_MAX_TX_RINGS; i++) {
ring = &bgmac->tx_ring[i];
- /* We don't implement unaligned addressing, so enable first */
- bgmac_dma_tx_enable(bgmac, ring);
+ if (!ring->unaligned)
+ bgmac_dma_tx_enable(bgmac, ring);
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_RINGLO,
lower_32_bits(ring->dma_base));
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_TX_RINGHI,
upper_32_bits(ring->dma_base));
+ if (ring->unaligned)
+ bgmac_dma_tx_enable(bgmac, ring);
ring->start = 0;
ring->end = 0; /* Points the slot that should *not* be read */
@@ -505,12 +520,14 @@ static void bgmac_dma_init(struct bgmac
ring = &bgmac->rx_ring[i];
- /* We don't implement unaligned addressing, so enable first */
- bgmac_dma_rx_enable(bgmac, ring);
+ if (!ring->unaligned)
+ bgmac_dma_rx_enable(bgmac, ring);
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGLO,
lower_32_bits(ring->dma_base));
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_RINGHI,
upper_32_bits(ring->dma_base));
+ if (ring->unaligned)
+ bgmac_dma_rx_enable(bgmac, ring);
for (j = 0, dma_desc = ring->cpu_base; j < ring->num_slots;
j++, dma_desc++) {
@@ -531,6 +548,7 @@ static void bgmac_dma_init(struct bgmac
}
bgmac_write(bgmac, ring->mmio_base + BGMAC_DMA_RX_INDEX,
+ ring->index_base +
ring->num_slots * sizeof(struct bgmac_dma_desc));
ring->start = 0;
--- a/drivers/net/ethernet/broadcom/bgmac.h
+++ b/drivers/net/ethernet/broadcom/bgmac.h
@@ -384,6 +384,8 @@ struct bgmac_dma_ring {
u16 mmio_base;
struct bgmac_dma_desc *cpu_base;
dma_addr_t dma_base;
+ u32 index_base; /* Used for unaligned rings only, otherwise 0 */
+ bool unaligned;
struct bgmac_slot_info slots[BGMAC_RX_RING_SLOTS];
};

12
target/linux/brcm47xx/patches-3.10/770-bgmac-phylib.patch
View file

@ -10,7 +10,7 @@
They can be found on BCM47xx SoCs and provide gigabit ethernet.
--- a/drivers/net/ethernet/broadcom/bgmac.c
+++ b/drivers/net/ethernet/broadcom/bgmac.c
@@ -1201,27 +1201,14 @@ static int bgmac_set_mac_address(struct
@@ -1219,27 +1219,14 @@ static int bgmac_set_mac_address(struct
static int bgmac_ioctl(struct net_device *net_dev, struct ifreq *ifr, int cmd)
{
struct bgmac *bgmac = netdev_priv(net_dev);
@ -45,7 +45,7 @@
}
static const struct net_device_ops bgmac_netdev_ops = {
@@ -1243,61 +1230,18 @@ static int bgmac_get_settings(struct net
@@ -1261,61 +1248,18 @@ static int bgmac_get_settings(struct net
{
struct bgmac *bgmac = netdev_priv(net_dev);
@ -111,7 +111,7 @@
static void bgmac_get_drvinfo(struct net_device *net_dev,
struct ethtool_drvinfo *info)
@@ -1308,6 +1252,7 @@ static void bgmac_get_drvinfo(struct net
@@ -1326,6 +1270,7 @@ static void bgmac_get_drvinfo(struct net
static const struct ethtool_ops bgmac_ethtool_ops = {
.get_settings = bgmac_get_settings,
@ -119,7 +119,7 @@
.get_drvinfo = bgmac_get_drvinfo,
};
@@ -1326,10 +1271,42 @@ static int bgmac_mii_write(struct mii_bu
@@ -1344,10 +1289,42 @@ static int bgmac_mii_write(struct mii_bu
return bgmac_phy_write(bus->priv, mii_id, regnum, value);
}
@ -162,7 +162,7 @@
mii_bus = mdiobus_alloc();
if (!mii_bus)
@@ -1360,7 +1337,29 @@ static int bgmac_mii_register(struct bgm
@@ -1378,7 +1355,29 @@ static int bgmac_mii_register(struct bgm
bgmac->mii_bus = mii_bus;
@ -195,7 +195,7 @@
kfree(mii_bus->irq);
--- a/drivers/net/ethernet/broadcom/bgmac.h
+++ b/drivers/net/ethernet/broadcom/bgmac.h
@@ -399,7 +399,10 @@ struct bgmac {
@@ -401,7 +401,10 @@ struct bgmac {
struct bcma_device *cmn; /* Reference to CMN core for BCM4706 */
struct net_device *net_dev;
struct napi_struct napi;