David Miller wrote:
Ok, this is rev2, changes:
1) Jumbo MTU support is now present. I got stuck on this for
a while because I didn't realize that resetting the RX
XMAC would reset the XMAC_MAX register. I thought that
was a TX XMAC resource, ho hum...
Fix this by re-initializing the TX MAC after resetting
the RX MAC.
2) Implementing support for jumbograms required a re-examination of
how TX queue handling was done.
Neptune can report the TX Head at a location which is in the middle
of a packet's group of descriptors for a multi segment packet.
Working around this would just overly complicate the code.
We don't need to use the TX Head register. Instead, track the
"pkt_cnt" field of the TX_CS register. The difference since the
last reading is the number of full TX frames we can reclaim from
the ring.
This is not only simpler, it allows us to only need one MMIO
access (for TX_CS) during a reclaim run instead of two (TX_CS
and TX_RING_HDL).
A side note, I'm purposefully not using TX mailbox support. It's
broken in Neptune. If you get the registers in the DMA mailbox, MK
and MMK are always both set in the TX_CS register. So even if you
write the MK and MB bits back to TX_CS to clear the interrupt, the
MMK propagates to MK and you thus get another interrupt. This
basically makes TX DMA mailbox support useless.
4) All register write accessors are now of the form xxx(reg, val)
instead of xxx(val, reg)
5) Kill PCI_DEVICE_ID_SUN_NEPTUNE define, unneeded.
Performance isn't the best, but the driver is reasonably solid. After
I flesh out the remaining features that need to be implemented I'll
take a closer look at that.
Enjoy.
commit 684a7c25fff607dc647f065761bb381f28bddbdb
Author: David S. Miller <[EMAIL PROTECTED]>
Date: Thu Sep 27 21:43:57 2007 -0700
[NIU]: Add Sun Neptune ethernet driver.
Signed-off-by: David S. Miller <[EMAIL PROTECTED]>
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 467532c..3c94c8f 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -2601,6 +2601,13 @@ config NETXEN_NIC
help
This enables the support for NetXen's Gigabit Ethernet card.
+config NIU
+ tristate "Sun Neptune 10Gbit Ethernet support"
+ depends on PCI
+ help
+ This enables support for cards based upon Sun's
+ Neptune chipset.
+
config PASEMI_MAC
tristate "PA Semi 1/10Gbit MAC"
depends on PPC64 && PCI
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 6220c50..cce379b 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -242,3 +242,4 @@ obj-$(CONFIG_NETCONSOLE) += netconsole.o
obj-$(CONFIG_FS_ENET) += fs_enet/
obj-$(CONFIG_NETXEN_NIC) += netxen/
+obj-$(CONFIG_NIU) += niu.o
diff --git a/drivers/net/niu.c b/drivers/net/niu.c
new file mode 100644
index 0000000..5b89559
--- /dev/null
+++ b/drivers/net/niu.c
Dave,
Couple of comments on Jumbo support
TX Side:
Can we rule of fragment size > MAX_TX_DESC_LEN? If that is not the case,
then the frags my need the same tx post and reclaim logic as the skb->data
RX Side
Since the MAC is set not to strip FCS bytes, the last page could
contain just 1 - 4 bytes of FCS. Not only this wastes the page but may
result on bug RX process where skb->len is wrong and a page with junk is
passed to the stack. In our off-the-tree driver, we check this condition
and repost the last page back to the rbr, if it contains just the FCS bytes.
Regards,
Matheos
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