Commit Graph

232 Commits

Author SHA1 Message Date
Tejun Heo 32032df6c2 Merge branch 'master' into percpu
Conflicts:
	arch/powerpc/platforms/pseries/hvCall.S
	include/linux/percpu.h
2010-01-05 09:17:33 +09:00
Barry Song d1be2e485b Blackfin: add support for TIF_NOTIFY_RESUME
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-12-15 00:16:52 -05:00
Mike Frysinger 7eb87fd3f1 Blackfin: BF537: push down error masks to avoid namespace pollution
The error masks are only needed in the BF537 demux error code, so instead
of needing all the short peripheral defines in global space, push these
masks into the one file where they are actually needed.  This fixes a
bunch of define collisions with common code (can/serial/etc...).

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Barry Song <barry.song@analog.com>
2009-12-15 00:16:11 -05:00
Yi Li 578d36f5e1 Blackfin: SMP: don't start up core b until its state has been completely onlined
When testing PREEMPT_RT kernel on BF561-EZKit, the kernel blocks while
booting.  When the kernel initializes the ethernet driver, it sleeps and
never wakes up.

The issue happens when the kernel waits for a timer for Core B to timeout
(the timers are per-cpu based: static DEFINE_PER_CPU(struct tvec_base *,
tvec_bases) = &boot_tvec_bases).

However, the ksoftirqd thread for Core B (note, the ksoftirqd thread is
also per-cpu based) cannot work properly, and the timers for Core B never
times out.

When ksoftirqd() for the first time runs on core B, it is possible core A
is still initializing core B (see smp_init() -> cpu_up() -> __cpu_up()).
So the "cpu_is_offline()" check may return true and ksoftirqd moves to
"wait_to_die".

So delay the core b start up until the per-cpu timers have been set up
fully.

Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-12-15 00:16:09 -05:00
Mike Frysinger 761ec44add Blackfin: pull in asm/dpmc.h for power defines
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-12-15 00:14:50 -05:00
Michael Hennerich 621dd24743 Blackfin: bf538: add support for extended GPIO banks
The GPIOs on ports C/D/E on the BF538/BF539 do not behave the same way as
the other ports on the part and the same way as all other Blackfin parts.
The MMRs are programmed slightly different and they cannot be used to
generate interrupts or wakeup a sleeping system.  Since these guys don't
fit into the existing code, create a simple gpiolib driver for them.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-12-15 00:14:05 -05:00
Michael Hennerich d887a1ce28 Blackfin: cpufreq: use a constant latency
PLL_LOCKCNT applies only to the PLL programming sequence which does not
apply to core and system clock dividers.  Writes to PLL_DIV to change the
CSEL/SSEL dividers take effect immediately.

There is still overhead in software in writing the new dividers, so just
use a value of 50us as this should be good enough.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-12-15 00:14:00 -05:00
Al Viro f8b7256096 Unify sys_mmap*
New helper - sys_mmap_pgoff(); switch syscalls to using it.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-12-11 06:44:29 -05:00
David S. Miller ff9c38bba3 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/mac80211/ht.c
2009-12-01 22:13:38 -08:00
Roel Kluin 05bad36ce7 Blackfin: fix memset in smp_send_reschedule() and -stop()
To set zeroes the sizeof the struct should be used rather
than sizeof the pointer, kzalloc does that.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-11-25 02:35:45 -05:00
Mike Frysinger a2ca78cee1 Blackfin: check for anomaly 05000475
Parts that have on-chip L2 SRAM cannot safely utilize writeback caching
mode, so reject any attempts to use it.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-11-25 02:35:41 -05:00
David S. Miller 3505d1a9fd Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/sfc/sfe4001.c
	drivers/net/wireless/libertas/cmd.c
	drivers/staging/Kconfig
	drivers/staging/Makefile
	drivers/staging/rtl8187se/Kconfig
	drivers/staging/rtl8192e/Kconfig
2009-11-18 22:19:03 -08:00
Rusty Russell dd17c8f729 percpu: remove per_cpu__ prefix.
Now that the return from alloc_percpu is compatible with the address
of per-cpu vars, it makes sense to hand around the address of per-cpu
variables.  To make this sane, we remove the per_cpu__ prefix we used
created to stop people accidentally using these vars directly.

Now we have sparse, we can use that (next patch).

tj: * Updated to convert stuff which were missed by or added after the
      original patch.

    * Kill per_cpu_var() macro.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
2009-10-29 22:34:15 +09:00
Arnaldo Carvalho de Melo a2e2725541 net: Introduce recvmmsg socket syscall
Meaning receive multiple messages, reducing the number of syscalls and
net stack entry/exit operations.

Next patches will introduce mechanisms where protocols that want to
optimize this operation will provide an unlocked_recvmsg operation.

This takes into account comments made by:

. Paul Moore: sock_recvmsg is called only for the first datagram,
  sock_recvmsg_nosec is used for the rest.

. Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
  works in the same fashion as the ppoll one.

  If the underlying protocol returns a datagram with MSG_OOB set, this
  will make recvmmsg return right away with as many datagrams (+ the OOB
  one) it has received so far.

. Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
  datagrams and then recvmsg returns an error, recvmmsg will return
  the successfully received datagrams, store the error and return it
  in the next call.

This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
where we will be able to acquire the lock only at batch start and end, not at
every underlying recvmsg call.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-12 23:40:10 -07:00
Robin Getz 96f1050d3d Blackfin: mass clean up of copyright/licensing info
Bill Gatliff & David Brownell pointed out we were missing some
copyrights, and licensing terms in some of the files in
./arch/blackfin, so this fixes things, and cleans them up.

It also removes:
 - verbose GPL text(refer to the top level ./COPYING file)
 - file names (you are looking at the file)
 - bug url (it's in the ./MAINTAINERS file)
 - "or later" on GPL-2, when we did not have that right

It also allows some Blackfin-specific assembly files to be under a BSD
like license (for people to use them outside of Linux).

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-07 04:36:26 -04:00
Ingo Molnar cdd6c482c9 perf: Do the big rename: Performance Counters -> Performance Events
Bye-bye Performance Counters, welcome Performance Events!

In the past few months the perfcounters subsystem has grown out its
initial role of counting hardware events, and has become (and is
becoming) a much broader generic event enumeration, reporting, logging,
monitoring, analysis facility.

Naming its core object 'perf_counter' and naming the subsystem
'perfcounters' has become more and more of a misnomer. With pending
code like hw-breakpoints support the 'counter' name is less and
less appropriate.

All in one, we've decided to rename the subsystem to 'performance
events' and to propagate this rename through all fields, variables
and API names. (in an ABI compatible fashion)

The word 'event' is also a bit shorter than 'counter' - which makes
it slightly more convenient to write/handle as well.

Thanks goes to Stephane Eranian who first observed this misnomer and
suggested a rename.

User-space tooling and ABI compatibility is not affected - this patch
should be function-invariant. (Also, defconfigs were not touched to
keep the size down.)

This patch has been generated via the following script:

  FILES=$(find * -type f | grep -vE 'oprofile|[^K]config')

  sed -i \
    -e 's/PERF_EVENT_/PERF_RECORD_/g' \
    -e 's/PERF_COUNTER/PERF_EVENT/g' \
    -e 's/perf_counter/perf_event/g' \
    -e 's/nb_counters/nb_events/g' \
    -e 's/swcounter/swevent/g' \
    -e 's/tpcounter_event/tp_event/g' \
    $FILES

  for N in $(find . -name perf_counter.[ch]); do
    M=$(echo $N | sed 's/perf_counter/perf_event/g')
    mv $N $M
  done

  FILES=$(find . -name perf_event.*)

  sed -i \
    -e 's/COUNTER_MASK/REG_MASK/g' \
    -e 's/COUNTER/EVENT/g' \
    -e 's/\<event\>/event_id/g' \
    -e 's/counter/event/g' \
    -e 's/Counter/Event/g' \
    $FILES

... to keep it as correct as possible. This script can also be
used by anyone who has pending perfcounters patches - it converts
a Linux kernel tree over to the new naming. We tried to time this
change to the point in time where the amount of pending patches
is the smallest: the end of the merge window.

Namespace clashes were fixed up in a preparatory patch - and some
stylistic fallout will be fixed up in a subsequent patch.

( NOTE: 'counters' are still the proper terminology when we deal
  with hardware registers - and these sed scripts are a bit
  over-eager in renaming them. I've undone some of that, but
  in case there's something left where 'counter' would be
  better than 'event' we can undo that on an individual basis
  instead of touching an otherwise nicely automated patch. )

Suggested-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <linux-arch@vger.kernel.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-09-21 14:28:04 +02:00
Mike Frysinger ea426e6c62 Blackfin: unify cache init functions
The CPLB implementations (mpu/nompu) had exact copies of the cacheinit
code.  Even the i/d cache functions are largely the same.  So unify them
both in the common kernel cache code.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:49 -04:00
Robin Getz dedfd5d7f2 Blackfin: workaround anomaly 05000283
Make sure our interrupt entry code with exact hardware errors handles
anomaly 05000283 (infinite stall in system MMR kill) so we don't stall
while under load.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:34 -04:00
Graf Yang 1794131471 Blackfin: handle the core timer interrupt with handle_percpu_irq on SMP
Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:29 -04:00
Mike Frysinger 926494943b Blackfin: optimize fixed code handling for the most common case
The majority of the time we are returning to user space, it is not in the
fixed atomic code region.  So rather than branch to a function where we
check the PC and return, do the check inline and branch only when needed.

Also, tweak some of the fixed code handling based on assumptions we are
aware of but cannot be expressed in C.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:28 -04:00
Mike Frysinger 3aa670419a Blackfin: punt dead cache locking code
No one uses these functions, and some are duplicate of existing C code.  So
just punt the whole thing.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:25 -04:00
Yi Li eb7bd9c461 Blackfin: cleanup sync handling when enabling/disabling cplbs
The handling of updating the [DI]MEM_CONTROL MMRs does not follow proper
sync procedures as laid out in the Blackfin programming manual.  So rather
than audit/fix every call location, create helper functions that do the
right things in order to safely update these MMRs.  Then convert all call
sites to use these new helper functions.

While we're fixing the code, drop the workaround for anomaly 05000125 as
that anomaly applies to old versions of silicon that we do not support.

Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 22:10:19 -04:00
Graf Yang 01b9f4b0ed Blackfin: improve double fault debug handling
Since the hardware only provides reporting for the last exception handled,
and the values are valid only when executing the exception handler, we
need to save the context for reporting at a later point.  While we do this
for one exception, it doesn't work properly when handling a second one as
the original exception is clobbered by the double fault.  So when double
fault debugging is enabled, create a dedicated shadow of these values and
save/restore out of there.  Now the crash report properly displays the
first exception as well as the second one.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:31:57 -04:00
Robin Getz 837ec2d56c Blackfin: catch hardware errors earlier during booting
Allow hardware errors to be caught during early portions of booting, and
leave something in the shadow console that people can use to debug their
system with (to be printed out by the bootloader on next reset).

This enables the hardare error interrupts in head.S, allowing us to find
hardware errors when they happen (well, as much as you can with a hardware
error) and prints out the trace if it is enabled.  This will catch errors
(like booting the wrong image on a 533) which previously resulted in a
infinite loop/hang, as well as random hardware errors before before
setup_arch().

To disable this debug only feature - turn off EARLY_PRINTK.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:31:44 -04:00
Philippe Gerum f4e129399c Blackfin: inline I-pipe bypass code in ret_from_exception
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:42 -04:00
Philippe Gerum 9ea7770fdb Blackfin: sanitize manual control of IPEND[4]
Cleanup is performed in two ways:

- remove extraneous updates of IPEND[4] w/ CONFIG_IPIPE,
  and document remaining use.

- substitute pop-reg-from-stack instructions with plain SP fixups in
  all save-RETI-then-discard patterns.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:40 -04:00
Philippe Gerum 7a7967dc1b Blackfin: document __ipipe_call_irqtail
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:38 -04:00
Philippe Gerum 70f4720232 Blackfin: allow EVT5 to preempt irqtail prologue (CONFIG_DEBUG_HWERR)
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:37 -04:00
Philippe Gerum fc9afb997f Blackfin: reuse evt_evt14 handler to perform irqtail epilogue
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:36 -04:00
Philippe Gerum 9703a73c98 Blackfin: use generic name for EVT14 handler
The purpose of the EVT14 handler may depend on whether CONFIG_IPIPE is
enabled, albeit its implementation can be the same in both cases. When
the interrupt pipeline is enabled, EVT14 can be used to raise the core
priority level for the running code; when CONFIG_IPIPE is off, EVT14
can be used to lower this level before running softirq handlers.

Rename evt14_softirq to evt_evt14 to pick an identifier that fits
both, which allows to reuse the same vector setup code as well.

Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:34 -04:00
Robin Getz ae4f073c40 Blackfin: make EVT3->EVT5 lowering more robust wrt IPEND[4]
We handle many exceptions at EVT5 (hardware error level) so that we can
catch exceptions in our exception handling code.  Today - if the global
interrupt enable bit (IPEND[4]) is set (interrupts disabled) our trap
handling code goes into a infinite loop, since we need interrupts to be
on to defer things to EVT5.

Normal kernel code should not trigger this for any reason as IPEND[4] gets
cleared early (when doing an interrupt context save) and the kernel stack
there should be sane (or something much worse is happening in the system).
But there have been a few times where this has happened, so this change
makes sure we dump a proper crash message even when things have gone south.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-09-16 21:28:28 -04:00
Julia Lawall 994e9a2e01 arch/blackfin: Add kmalloc NULL tests
Check that the result of kmalloc is not NULL before passing it to other
functions.

In the first two cases, the new code returns -ENOMEM, which seems
compatible with what is done for similar functions for other architectures.

In the last two cases, the new code fails silently, ie just returns,
because the function has void return type.

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
expression *x;
identifier f;
constant char *C;
@@

x = \(kmalloc\|kcalloc\|kzalloc\)(...);
... when != x == NULL
    when != x != NULL
    when != (x || ...)
(
kfree(x)
|
f(...,C,...,x,...)
|
*f(...,x,...)
|
*x->f
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-07-16 01:52:54 -04:00
Michael Hennerich c70c754ff9 Blackfin: drop per-cpu loops_per_jiffy tracking
On Blackfin SMP, a per-cpu loops_per_jiffy is pointless since both cores
always run at the same CCLK.  In addition, the current implementation has
flaws since the main consumer for loops_per_jiffy (asm/delay.h) uses the
global kernel loops_per_jiffy and not the per_cpu one.  So punt all of the
per-cpu handling and go back to the global shared one.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-07-16 01:52:44 -04:00
Robin Getz 1997660cea Blackfin: cleanup code a bit with comments and defines
Improve the assembly with a few explanatory comments and use symbolic
defines rather than numeric values for bit positions.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-07-16 01:39:39 -04:00
Mike Frysinger 5ecf3e03cd Blackfin: hook up new perf_counter_open syscall
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-22 21:47:40 -04:00
Jie Zhang 41ba653f24 Blackfin: decouple unrelated cache settings to get exact behavior
The current cache options don't really represent the hardware features.
They end up setting different aspects of the hardware so that the end
result is to turn on/off the cache.  Unfortunately, when we hit cache
problems with the hardware, it's difficult to test different settings to
root cause the problem.  The current settings also don't cleanly allow for
different caching behaviors with different regions of memory.

So split the configure options such that they properly reflect the settings
that are applied to the hardware.

Signed-off-by: Jie Zhang <jie.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-22 21:15:59 -04:00
Philippe Gerum a40494a62a Blackfin: allow CONFIG_TICKSOURCE_GPTMR0 with interrupt pipeline
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-22 21:15:54 -04:00
Mike Frysinger cf8d943260 Blackfin: only build irqpanic.c when needed
The irq_panic function is only used when CONFIG_DEBUG_ICACHE_CHECK is
enabled, so move the conditional build to the Makefile rather than
wrapping all of the contents of the file.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-18 21:40:49 -04:00
Mike Frysinger c36953419b Blackfin: use common test_bit() rather than __test_bit()
Convert to test_bit() as that is what pretty much everyone uses and allows
us to migrate asm/bitops.h to the asm-generic version.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-18 21:40:40 -04:00
Mike Frysinger 61cdd7a28f Blackfin: hook up new rt_tgsigqueueinfo syscall
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-13 07:23:18 -04:00
Sonic Zhang 86f2008bf5 Blackfin: fix deadlock in SMP IPI handler
When a low priority interrupt (like ethernet) is triggered between 2 high
priority IPI messages, a deadlock in disable_irq() is hit by the second
IPI handler.  This is because the second IPI message is queued within the
first IPI handler, but the handler doesn't process all messages, and new
ones are inserted rather than appended.  So now we process all the pending
messages, and append new ones to the pending list.

URL: http://blackfin.uclinux.org/gf/tracker/5226
Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-13 07:20:09 -04:00
Sonic Zhang 47e9dedb72 Blackfin: add blackfin_invalidate_entire_icache for SMP systems
The KGDB code uses this when switching processors to make sure the icache
is in a valid state.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-13 07:20:07 -04:00
Robin Getz 16aadcb680 Blackfin: only handle CPLB protection violations when MPU is enabled
We don't need to handle CPLB protection violations unless we are running
with the MPU on.  Fix the entry code to call common trap_c, and remove the
code which is never run.  This allows the traps test suite to run on older
boards with the MPU disabled.

URL: http://blackfin.uclinux.org/gf/tracker/5129
Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-13 07:20:06 -04:00
Mike Frysinger 780172bf87 Blackfin: check SIC defines rather than variant names
Rather than having to maintain a hard coded list of Blackfin variants, use
the SIC defines themselves.  This fixes build problems on BF51x/BF538 under
some configurations as they were missing from one of the lists.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:58 -04:00
Mike Frysinger 37082511f0 Blackfin: fix command line corruption with DEBUG_DOUBLEFAULT
Commit 6b3087c6 (which introduced Blackfin SMP) broke command line passing
when the DEBUG_DOUBLEFAULT config option was enabled.  Switch the code to
using a scratch register and not R7 which holds the command line.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:52 -04:00
Graf Yang d1800fe0e5 Blackfin: drop unused reserve_pda() function
The Per-processor Data Area isn't actually reserved by this function, and
all it ended up doing was issuing a printk(), so punt it.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:49 -04:00
Robin Getz b9a3899d59 Blackfin: make deferred hardware errors more exact
Hardware errors on the Blackfin architecture are queued by nature of the
hardware design.  Things that could generate a hardware level queue up at
the system interface and might not process until much later, at which
point the system would send a notification back to the core.

As such, it is possible for user space code to do something that would
trigger a hardware error, but have it delay long enough for the process
context to switch.  So when the hardware error does signal, we mistakenly
evaluate it as a different process or as kernel context and panic (erp!).
This makes it pretty difficult to find the offending context.  But wait,
there is good news somewhere.

By forcing a SSYNC in the interrupt entry, we force all pending queues at
the system level to be processed and all hardware errors to be signaled.
Then we check the current interrupt state to see if the hardware error is
now signaled.  If so, we re-queue the current interrupt and return thus
allowing the higher priority hardware error interrupt to process properly.
Since we haven't done any other context processing yet, the right context
will be selected and killed.  There is still the possibility that the
exact offending instruction will be unknown, but at least we'll have a
much better idea of where to look.

The downside of course is that this causes system-wide syncs at every
interrupt point which results in significant performance degradation.
Since this situation should not occur in any properly configured system
(as hardware errors are triggered by things like bad pointers), make it a
debug configuration option and disable it by default.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:44 -04:00
Mike Frysinger 97b070c8e7 Blackfin: add note about anomaly 05000242 being worked around
Document anomaly 05000242 workaround in source code.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:42 -04:00
Graf Yang 5ba766752d Blackfin: work around anomaly 05000220
When possible, work around anomaly 05000220 (external memory is write
back cached, but L2 is not cached).  If not possible, detect the
conditions at build time and reject any qualifying configurations.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:41 -04:00
Graf Yang 1fa9be72b5 Blackfin: add support for gptimer0 as a tick source
For systems where the core cycles are not a usable tick source (like SMP
or cycles gets updated), enable gptimer0 as an alternative.

Signed-off-by: Graf Yang <graf.yang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-06-12 06:11:37 -04:00