Commit Graph

25553 Commits

Author SHA1 Message Date
Ingo Korb
b08b5ad947 Char: stallion, fix oops during init with ISA cards
The stallion driver oopses while initializing ISA cards due to an
uninitialized variable.  This patch changes the initialisation order to
match the PCI code path.

Signed-off-by: Ingo Korb <ml@akana.de>
Acked-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Ben Dooks
1e27dbe774 SM501: Check SM501 ID register on initialisation
When binding the driver, check the ID register for a valid identity, in case
the SM501 is not functioning correctly.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Ben Dooks
819062219a SM501: Clock updates and checks
Ensure that the M1XCLK and MCLK are sourced from the same PLL (and refuse to
bind the driver if they are not).

Update the PCI to safe initialisation values, as 72MHz is the maximum clock
for 33MHz PCI bus mastering.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Ben Dooks
5136237bc3 SM501: Fix sm501_init_reg() mask/set order
The order of the set and mask operation in sm501_init_reg() was setting and
then masking the bits set.  Correct the order so that we do not end up with
288MHz SDRAM clocks on certain systems.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Ben Dooks
b5913bbd2d SM501: initialise SDRAM clock before bus clocks
This init sequence of setting the SDRAM clock before the bus clock is
recommend by Silicon Motion to stop problems with writes not sticking into
registers.

Signed-off-by: Vincent Sanders <vince@simtec.co.uk>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Ben Dooks
331d74750e SM501: suspend support
This patch adds support for suspending the core (mfd driver) of the SM501.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:11 -07:00
Egmont Koblinger
1ed8a2b3c5 console UTF-8 fixes (fix)
Recently my console UTF-8 patch went mainline.  Here is an additional patch
that fixes two nasty issues and improves a third one, namely:

1. My patch changed the behavior if a glyph is not found in the Unicode
   mapping table. Previously for Unicode values less than 256 or 512 the
   kernel tried to display the glyph from that position of the glyph table,
   which could lead to a different accented letter being displayed. I
   removed this fallback possibility and changed it to display the
   replacement symbol.

   As Behdad pointed out, some fonts (e.g. sun12x22 from the kbd package)
   lack Unicode mapping information, hence all you get is lots of question
   marks. Though theoretically it's actually a user-space bug (the font
   should be fixed), Behdad and I both believe that it'd be good to work
   around in the kernel by re-introducing the fallback solution for ASCII
   characters only. This sounds a quite reasonable decision, since all fonts
   ship the ASCII characters in the first 128 positions. This way users
   won't be surprised by lots of question marks just because s/he issued a
   not-so-perfectly parameterized setfont command. As this fallback is only
   re-introduced for code points below 128, you still won't see an accented
   letter replaced by another, but at least you'll always get the English
   letters right.

2. My patch introduced "question mark with inverted color attributes" as a
   last resort fallback glyph. Though it perfectly works on VGA console, on
   framebuffer you may end up with question marks that are highlighed but
   shouldn't be, and normal characters that are accidentally highlighed.
   This is caused by missing FLUSHes when changing the color attribute.

3. I've updated the table of double-width character based on Markus's
   updated version. Only ten new code poings (one interval) is added.

Signed-off-by: Egmont Koblinger <egmont@uhulinux.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:10 -07:00
Jean Delvare
6d79af701d hwmon/coretemp: fix a broken error path
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Rudolf Marek <r.marek@assembler.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-24 08:59:10 -07:00
Len Brown
629cf6d74b Pull now into release branch 2007-06-23 10:58:24 -04:00
Venkatesh Pallipadi
d5a3d32a04 ACPI: fix 2.6.20 SMP boot regression
Always disable/enable interrupts in the acpi idle routine,
even in the error path.

This is required as the 2.6.20 change in git commit d331e739f5ad2aaa9...
"Fix interrupt race in idle callback" expects the idle handler
to enable interrupt before returning.

There was a case in acpi idle routine, in which interrupt was not being
enabled before return, which caused the system to hang at bootup, while
enabling C-states on an SMP system.

The signature of the hang was that "processor.nocst"
was required to enable boot.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2007-06-23 10:57:28 -04:00
Olaf Hering
e2f1f19272 x86_64: Fix only make Macintosh drivers default on Macs
Include PPC_MAC in the default too, not only MAC which only covers
m68k MACs.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-06-22 18:41:18 -07:00
Linus Torvalds
4beb2584be Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
  IB/mlx4: Correct max_srq_wr returned from mlx4_ib_query_device()
  IPoIB/cm: Remove dead definition of struct ipoib_cm_id
  IPoIB/cm: Fix interoperability when MTU doesn't match
  IPoIB/cm: Initialize RX before moving QP to RTR
  IB/umem: Fix possible hang on process exit
2007-06-22 11:10:34 -07:00
Linus Torvalds
79d9a72f87 Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart
* master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart:
  [AGPGART] intel_agp: don't load if no IGD and AGP port
2007-06-21 15:59:11 -07:00
Linus Torvalds
9738cbe321 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6:
  [PARISC] unwinder improvements
  [PARISC] Fix unwinder on 64-bit kernels
  [PARISC] Handle wrapping in expand_upwards()
  [PARISC] stop lcd driver from stripping initial whitespace
2007-06-21 15:57:50 -07:00
Julian Stecklina
d2f1c0fa2b [PARISC] stop lcd driver from stripping initial whitespace
Signed-off-by: Julian Stecklina <der_julian@web.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2007-06-21 17:46:19 -04:00
Jack Morgenstein
c8681f1401 IB/mlx4: Correct max_srq_wr returned from mlx4_ib_query_device()
We need to keep a spare entry in the SRQ so that there always is a
next WQE available when posting receives (so that we can tell the
difference between a full queue and an empty queue).  So subtract 1
from the value HW gives us before reporting the limit on SRQ entries
to consumers.

Found by Mellanox QA.

Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 13:39:10 -07:00
Roland Dreier
13ef5f44c3 IPoIB/cm: Remove dead definition of struct ipoib_cm_id
It's completely unused.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 13:39:08 -07:00
Michael S. Tsirkin
82c3aca6ad IPoIB/cm: Fix interoperability when MTU doesn't match
IPoIB connected mode currently rejects a connection request unless the
supported MTU is >= the local netdevice MTU. This breaks
interoperability with implementations that might have tweaked
IPOIB_CM_MTU, and there's real no longer a reason to do so: this test
is just a leftover from when we did not tweak MTU per-connection.  Fix
this by making the test as permissive as possible.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 13:38:08 -07:00
Michael S. Tsirkin
3ec7393a68 IPoIB/cm: Initialize RX before moving QP to RTR
Fix a crasher bug in IPoIB CM: once a QP is in the RTR state, a
receive completion (or even an asynchronous error) might be observed
on this QP, so we have to initialize all of our receive data
structures before moving to the RTR state.

As an optimization (since modify_qp might take a long time), the
jiffies update done when moving RX to the passive_ids list is also
left in place to reduce the chance of the RX being misdetected as
stale.

This fixes bug <https://bugs.openfabrics.org/show_bug.cgi?id=662>.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 13:03:50 -07:00
Roland Dreier
24bce50803 IB/umem: Fix possible hang on process exit
If ib_umem_release() is called after ib_uverbs_close() sets context->closing,
then a process can get stuck in a D state, because the code boils down to

	if (down_write_trylock(&mm->mmap_sem))
		down_write(&mm->mmap_sem);

which is obviously a stupid instant deadlock.  Fix the code so that we
only try to take the lock once.

This bug was introduced in commit f7c6a7b5 ("IB/uverbs: Export
ib_umem_get()/ib_umem_release() to modules") which fortunately never
made it into a release, and was reported by Pete Wyckoff <pw@osc.edu>.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 11:05:58 -07:00
Wang Zhenyu
47d46379eb [AGPGART] intel_agp: don't load if no IGD and AGP port
After i915 chip, GMCH has no AGP port. Origin bridge driver in device
table will try to access illegal regs like APBASE, APSIZE, etc. This
may cause problem.

So mark them as NULL in the table, we won't load if no IGD got detect
and bridge has no AGP port.

Signed-off-by: Wang Zhenyu <zhenyu.z.wang@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2007-06-21 12:49:11 -04:00
Linus Torvalds
f1518a088b Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  fix module_param mistake in it821x
  ahci: fix PORTS_IMPL override
  kerneldoc fix in libata
  libata: more NONCQ devices
  pata_it821x: (partially) fix DMA in RAID mode
  PATA: Add the MCP73/77 support to PATA driver
2007-06-20 17:11:44 -07:00
Stas Sergeev
5fe675e2b3 fix module_param mistake in it821x
The attached patch fixes a trivial
mistake in a MODULE_PARAM_DESC of pata_it821x
driver. The parameter name in MODULE_PARAM_DESC
should match the one in module_param_named.

Signed-off-by: Stas Sergeev <stsp@aknet.ru>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Tejun Heo
a3d2cc5e74 ahci: fix PORTS_IMPL override
If PORTS_IMPL register is zero, ahci initialize it to full mask
corresponding to nr_ports in the CAP register.  hpriv->cap, which is
initialized at the end of the function, is incorrectly used as value
of CAP causing ahci to always override PORTS_IMPL to 0x1 if it's zero.
Fix it.

This fixes a bug where early ich6 ahci can only access the first port.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Henrik Kretzschmar
3fae450c68 kerneldoc fix in libata
Fix parameter name from ata_dev_reread_id() in libata-core.c for kerneldoc.

Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Tejun Heo
2f8fcebbf5 libata: more NONCQ devices
More for the NCQ blacklist.  One hitachi and one raptor.  Other
members of these families of drives are already on the list, so no
surprises.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Bartlomiej Zolnierkiewicz
374abf2cb1 pata_it821x: (partially) fix DMA in RAID mode
Code intended to check DMA status was checking DMA command register.

Moreover firmware seems to "forget" to set DMA capable bit for the
slave device (at least in RAID mode but without ITE RAID volumes) so
check device ID for DMA capable bit when deciding whether to use DMA
and remove DMA status check completely.

Thanks to Pavol Simo for the bugreport and testing the initial fix.

This change unfortunately still doesn't fix DMA in RAID mode (which
works fine with IDE it821x) but Alan is working on the missing pieces
(pata_it821x vs libata EH issues).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Peer Chen
9f7897554e PATA: Add the MCP73/77 support to PATA driver
Add the MCP73/MCP77 support to PATA driver.
The patch base on kernel 2.6.22-rc4

Signed-off-by: Peer Chen <peerchen@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:56:21 -04:00
Divy Le Ray
2090dee420 cxgb3 - MAC watchdog update
Fix variables initialization and usage in the MAC watchdog.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:16:59 -04:00
Divy Le Ray
7b581a0fa8 cxgb3 - Stop mac RX when changing MTU
Rx traffic needs to be halted when the MTU is changed
to avoid a potential chip hang.
Reset/restore MAC filters around a MTU change.
Also fix the pause frames high materwark setting.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:16:59 -04:00
Divy Le Ray
c706bfb52a cxgb3 - Fix direct XAUI support
Check all lanes for link status on direct XAUI cards.
Don't assume that direct XAUI always uses XGMAC 1.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:16:58 -04:00
Divy Le Ray
890de33283 cxgb3 - fix netpoll hanlder
Fix netpoll handler to work with line interrupt, msi and msi-x.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:16:58 -04:00
Divy Le Ray
e360b5628f cxgb3 - fix skb->dev dereference
eth_type_trans() now sets skb->dev.
References to skb->dev should happen after it is called.

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:16:58 -04:00
Gregory Haskins
d41f2d17f8 natsemi irq flags
The spinlock irq flags should be a unsigned long to properly support 64 bit

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:15:04 -04:00
Tim Mann
2cc49a5ca1 forcedeth: use unicast receive mode for WoL
I happened to notice that a system with an NVidia NIC using the
forcedeth driver won't wake-on-LAN if the interface was in promiscuous
mode when you power off.  By experiment, it looks like
the hardware needs to have NvRegPacketFilterFlags set to
NVREG_PFF_ALWAYS|NVREG_PFF_MYADDR (i.e., receive unicast packets to my
address) in order for WoL to work.

Jeff Garzik writes: "NVIDIA says the patch looks OK."  I didn't venture
to insert a signed-off-by line with his name on it, though.

Signed-off-by: Tim Mann <mann@vmware.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:15:04 -04:00
Martin Schwidefsky
d46146274b s390: netiucv inlining cleanup
The recent iucv rework patches re-introduced some unnecessary inlines.
Remove them again.

Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Thomas Gleixner
bfac0d0b6c s390: netiucv spinlock initializer cleanup
spinlock initializer cleanup in netiucv.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Ursula Braun
651bbc6224 s390: don't call iucv_path_connect from tasklet context
net/iucv/iucv.c creates the requirement for
iucv_path_connect not to be called from tasklet context anymore.
An extra checking is added in case of a failing netiucv_tx
to fulfil this requirement for netiucv.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Cornelia Huck
dc5bc0cabd s390: Use ccw_device_get_id() in qeth/claw drivers
Use ccw_device_get_id() to get a device number
instead of parsing the ccw device's bus id.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Frank Pavlic
cd3e76ebcb s390: qeth: wrong packet length in qdio header
Packets Length in qdio header is broken when using
EDDP on Layer2 devices. This leads to skb_under_panic on receiver
system when running on z/VM GuestLAN devices.

Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Ursula Braun
add3f2fa7a s390: avoid inconsistent lock state in qeth
ipv6_regen_rndid in net/ipv6/addrconf.c makes use of "write_lock_bh"
for its inet6_dev->lock. It may run in softirq-context.
qeth makes use of "read_lock" for the same inet6_dev->lock.
To avoid a potential deadlock situation, qeth should make use of
"read_lock_bh" for its usages of inet6_dev->lock.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Ursula Braun
d81ef0fb76 s390: qeth driver does not recover
While first recovery continues, the card issues
a STARTLAN command itself. In this case qeth
schedules another recovery. This second
recovery is cancelled because of an already running first recovery.
Stop first recovery in case of 0xe080.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:42 -04:00
Ursula Braun
d78f6642be s390: print correct level for HiperSockets devices
For real HiperSockets the EBCDIC-ASCII conversion is not necessary.
This is only needed for z/VM GuestLAN devices.

Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:41 -04:00
Jay Vosburgh
031ae4deb0 bonding: Fix 802.3ad no carrier on "no partner found" instance
Modify carrier state determination for 802.3ad mode to comply
with section 43.3.9 of IEEE 802.3, which requires that "Links that are
not successful candidates for aggregation (e.g., links that are attached
to other devices that cannot perform aggregation or links that have been
manually configured to be non-aggregatable) are enabled to operate as
individual IEEE 802.3 links."

	Bug reported by Laurent Chavey <chavey@google.com>.  This patch
is an updated version of his patch that changes the wording of
commentary and adds an update to the driver version.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Laurent Chavey <chavey@google.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:41 -04:00
Jay Vosburgh
3201e656ce bonding: Fix use after free in unregister path
The following patch (based on a patch from Stephen Hemminger
<shemminger@linux-foundation.org>) removes use after free conditions in
the unregister path for the bonding master.  Without this patch, an
operation of the form "echo -bond0 > /sys/class/net/bonding_masters"
would trigger a NULL pointer dereference in sysfs.  I was not able to
induce the failure with the non-sysfs code path, but for consistency I
updated that code as well.

	I also did some testing of the bonding /proc file being open
while the bond is being deleted, and didn't see any problems there.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:12:41 -04:00
Stephen Hemminger
3a2c892daa spidernet: checksum and ethtool
It doesn't look like spidernet hardware can really checksum all protocols,
the code looks like it does IPV4 only.  If so, it should use NETIF_F_IP_CSUM
instead of NETIF_F_HW_CSUM.

The driver doesn't need it's own get/set for ethtool tx csum, and it
should use the standard ethtool_op_get_link.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:09:33 -04:00
Linas Vepstas
128c6e2e51 spidernet: turn off descriptor chain end interrupt.
At some point, the transmit descriptor chain end interrupt (TXDCEINT)
was turned on. This is a mistake; and it damages small packet
transmit performance, as it results in a huge storm of interrupts.
Turn it off.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:09:33 -04:00
Linas Vepstas
c3d1182a53 spidernet: silence the ramfull messages
Although the previous patch resolved issues with hangs when the
RX ram full interrupt is encountered, there are still situations
where lots of RX ramfull interrupts arrive, resulting in a noisy
log in syslog. There is no need for this.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:09:33 -04:00
Linas Vepstas
2bf27a0d49 spidernet: Don't terminate the RX ring
The terminated RX ring will cause trouble during the RX ram full
conditions, leading to a hung driver, as the hardware can't find
the next descr.  There is no real reason to terminate the RX ring;
it doesn't make the operation any smooother, and it does
require an extra sync. So don't do it.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:09:33 -04:00
Linas Vepstas
4c4bd5a97a spidernet: Cure RX ram full bug
This patch fixes a rare deadlock that can occur when the kernel
is not able to empty out the RX ring quickly enough. Below follows
a detailed description of the bug and the fix.

As long as the OS can empty out the RX buffers at a rate faster than
the hardware can fill them, there is no problem. If, for some reason,
the OS fails to empty the RX ring fast enough, the hardware GDACTDPA
pointer will catch up to the head, notice the not-empty condition,
ad stop. However, RX packets may still continue arriving on the wire.
The spidernet chip can save some limited number of these in local RAM.
When this local ram fills up, the spider chip will issue an interrupt
indicating this (GHIINT0STS will show ERRINT, and the GRMFLLINT bit
will be set in GHIINT1STS).  When te RX ram full condition occurs,
a certain bug/feature is triggered that has to be specially handled.
This section describes the special handling for this condition.

When the OS finally has a chance to run, it will empty out the RX ring.
In particular, it will clear the descriptor on which the hardware had
stopped. However, once the hardware has decided that a certain
descriptor is invalid, it will not restart at that descriptor; instead
it will restart at the next descr. This potentially will lead to a
deadlock condition, as the tail pointer will be pointing at this descr,
which, from the OS point of view, is empty; the OS will be waiting for
this descr to be filled. However, the hardware has skipped this descr,
and is filling the next descrs. Since the OS doesn't see this, there
is a potential deadlock, with the OS waiting for one descr to fill,
while the hardware is waiting for a differen set of descrs to become
empty.

A call to show_rx_chain() at this point indicates the nature of the
problem. A typical print when the network is hung shows the following:

net eth1: Spider RX RAM full, incoming packets might be discarded!
net eth1: Total number of descrs=256
net eth1: Chain tail located at descr=255
net eth1: Chain head is at 255
net eth1: HW curr desc (GDACTDPA) is at 0
net eth1: Have 1 descrs with stat=xa0800000
net eth1: HW next desc (GDACNEXTDA) is at 1
net eth1: Have 127 descrs with stat=x40800101
net eth1: Have 1 descrs with stat=x40800001
net eth1: Have 126 descrs with stat=x40800101
net eth1: Last 1 descrs with stat=xa0800000

Both the tail and head pointers are pointing at descr 255, which is
marked xa... which is "empty". Thus, from the OS point of view, there
is nothing to be done. In particular, there is the implicit assumption
that everything in front of the "empty" descr must surely also be empty,
as explained in the last section. The OS is waiting for descr 255 to
become non-empty, which, in this case, will never happen.

The HW pointer is at descr 0. This descr is marked 0x4.. or "full".
Since its already full, the hardware can do nothing more, and thus has
halted processing. Notice that descrs 0 through 254 are all marked
"full", while descr 254 and 255 are empty. (The "Last 1 descrs" is
descr 254, since tail was at 255.) Thus, the system is deadlocked,
and there can be no forward progress; the OS thinks there's nothing
to do, and the hardware has nowhere to put incoming data.

This bug/feature is worked around with the spider_net_resync_head_ptr()
routine. When the driver receives RX interrupts, but an examination
of the RX chain seems to show it is empty, then it is probable that
the hardware has skipped a descr or two (sometimes dozens under heavy
network conditions). The spider_net_resync_head_ptr() subroutine will
search the ring for the next full descr, and the driver will resume
operations there.  Since this will leave "holes" in the ring, there
is also a spider_net_resync_tail_ptr() that will skip over such holes.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-06-20 19:09:32 -04:00