[PATCH] sis190: the size of the Rx buffer is constrained
Add a restriction to the size of the Rx buffer
SiS driver forces the size of any Rx buffer to be a multiple of 64 bit.
I would not be surprized that it goes along with some alignment issues
which have been experienced before. So far it does not make much of a
difference (both drivers use 1536 bytes buffer).
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/net/sis190.c b/drivers/net/sis190.c
index 1e8e711..2229698 100644
--- a/drivers/net/sis190.c
+++ b/drivers/net/sis190.c
@@ -69,6 +69,7 @@
#define TX_RING_BYTES (NUM_TX_DESC * sizeof(struct TxDesc))
#define RX_RING_BYTES (NUM_RX_DESC * sizeof(struct RxDesc))
#define RX_BUF_SIZE 1536
+#define RX_BUF_MASK 0xfff8
#define SIS190_REGS_SIZE 0x80
#define SIS190_TX_TIMEOUT (6*HZ)
@@ -400,7 +401,7 @@
u32 eor = le32_to_cpu(desc->size) & RingEnd;
desc->PSize = 0x0;
- desc->size = cpu_to_le32(rx_buf_sz | eor);
+ desc->size = cpu_to_le32((rx_buf_sz & RX_BUF_MASK) | eor);
wmb();
desc->status = cpu_to_le32(OWNbit | INTbit);
}
@@ -924,6 +925,11 @@
unsigned int mtu = dev->mtu;
tp->rx_buf_sz = (mtu > RX_BUF_SIZE) ? mtu + ETH_HLEN + 8 : RX_BUF_SIZE;
+ /* RxDesc->size has a licence to kill the lower bits */
+ if (tp->rx_buf_sz & 0x07) {
+ tp->rx_buf_sz += 8;
+ tp->rx_buf_sz &= RX_BUF_MASK;
+ }
}
static int sis190_open(struct net_device *dev)