Revert "skge: fix ram buffer size calculation"
This reverts commit 7fb7ac241162dc51ec0f7644d4a97b2855213c32.
Heikki Orsila reports that it causes a regression:
"Doing
nc host port < /dev/zero
on a sending machine (not skge) to an skge machine that is receiving:
nc -l -p port >/dev/null
with ~60 MiB/s speed, causes the interface go malfunct. A slow
transfer doesn't cause a problem."
See
http://bugzilla.kernel.org/show_bug.cgi?id=9321
for some more information.
There is a workaround (also reported by Heikki):
"After some fiddling, I noticed that not changing the register write
order on patch:
+ skge_write32(hw, RB_ADDR(q, RB_END), end);
skge_write32(hw, RB_ADDR(q, RB_WP), start);
skge_write32(hw, RB_ADDR(q, RB_RP), start);
- skge_write32(hw, RB_ADDR(q, RB_END), end);
fixes the visible effect.. Possibly not the root cause of the
problem, but changing the order back fixes networking here."
but that has yet to be ack'ed or tested more widely, so the whole
problem-causing commit gets reverted until this is resolved properly.
Bisected-and-requested-by: Heikki Orsila <shdl@zakalwe.fi>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/net/skge.c b/drivers/net/skge.c
index b9961dc..6d62250 100644
--- a/drivers/net/skge.c
+++ b/drivers/net/skge.c
@@ -2512,31 +2512,32 @@
return err;
}
-/* Assign Ram Buffer allocation to queue */
-static void skge_ramset(struct skge_hw *hw, u16 q, u32 start, u32 space)
+static void skge_ramset(struct skge_hw *hw, u16 q, u32 start, size_t len)
{
u32 end;
- /* convert from K bytes to qwords used for hw register */
- start *= 1024/8;
- space *= 1024/8;
- end = start + space - 1;
+ start /= 8;
+ len /= 8;
+ end = start + len - 1;
skge_write8(hw, RB_ADDR(q, RB_CTRL), RB_RST_CLR);
skge_write32(hw, RB_ADDR(q, RB_START), start);
- skge_write32(hw, RB_ADDR(q, RB_END), end);
skge_write32(hw, RB_ADDR(q, RB_WP), start);
skge_write32(hw, RB_ADDR(q, RB_RP), start);
+ skge_write32(hw, RB_ADDR(q, RB_END), end);
if (q == Q_R1 || q == Q_R2) {
- u32 tp = space - space/4;
-
/* Set thresholds on receive queue's */
- skge_write32(hw, RB_ADDR(q, RB_RX_UTPP), tp);
- skge_write32(hw, RB_ADDR(q, RB_RX_LTPP), space/4);
- } else if (hw->chip_id != CHIP_ID_GENESIS)
- /* Genesis Tx Fifo is too small for normal store/forward */
+ skge_write32(hw, RB_ADDR(q, RB_RX_UTPP),
+ start + (2*len)/3);
+ skge_write32(hw, RB_ADDR(q, RB_RX_LTPP),
+ start + (len/3));
+ } else {
+ /* Enable store & forward on Tx queue's because
+ * Tx FIFO is only 4K on Genesis and 1K on Yukon
+ */
skge_write8(hw, RB_ADDR(q, RB_CTRL), RB_ENA_STFWD);
+ }
skge_write8(hw, RB_ADDR(q, RB_CTRL), RB_ENA_OP_MD);
}
@@ -2564,7 +2565,7 @@
struct skge_port *skge = netdev_priv(dev);
struct skge_hw *hw = skge->hw;
int port = skge->port;
- u32 ramaddr, ramsize, rxspace;
+ u32 chunk, ram_addr;
size_t rx_size, tx_size;
int err;
@@ -2619,15 +2620,14 @@
spin_unlock_bh(&hw->phy_lock);
/* Configure RAMbuffers */
- ramsize = (hw->ram_size - hw->ram_offset) / hw->ports;
- ramaddr = hw->ram_offset + port * ramsize;
- rxspace = 8 + (2*(ramsize - 16))/3;
+ chunk = hw->ram_size / ((hw->ports + 1)*2);
+ ram_addr = hw->ram_offset + 2 * chunk * port;
- skge_ramset(hw, rxqaddr[port], ramaddr, rxspace);
- skge_ramset(hw, txqaddr[port], ramaddr + rxspace, ramsize - rxspace);
-
+ skge_ramset(hw, rxqaddr[port], ram_addr, chunk);
skge_qset(skge, rxqaddr[port], skge->rx_ring.to_clean);
+
BUG_ON(skge->tx_ring.to_use != skge->tx_ring.to_clean);
+ skge_ramset(hw, txqaddr[port], ram_addr+chunk, chunk);
skge_qset(skge, txqaddr[port], skge->tx_ring.to_use);
/* Start receiver BMU */
@@ -3591,12 +3591,15 @@
if (hw->chip_id == CHIP_ID_GENESIS) {
if (t8 == 3) {
/* special case: 4 x 64k x 36, offset = 0x80000 */
- hw->ram_size = 1024;
- hw->ram_offset = 512;
+ hw->ram_size = 0x100000;
+ hw->ram_offset = 0x80000;
} else
hw->ram_size = t8 * 512;
- } else /* Yukon */
- hw->ram_size = t8 ? t8 * 4 : 128;
+ }
+ else if (t8 == 0)
+ hw->ram_size = 0x20000;
+ else
+ hw->ram_size = t8 * 4096;
hw->intr_mask = IS_HW_ERR;