Commit Graph

54449 Commits

Author SHA1 Message Date
Stephen Warren
499ef7a5c4 ARM: tegra: Prevent requeuing in-progress DMA requests
If a request already in the queue is passed to tegra_dma_enqueue_req,
tegra_dma_req.node->{next,prev} will end up pointing to itself instead
of at tegra_dma_channel.list, which is the way a the end-of-list
should be set up. When the DMA request completes and is list_del'd,
the list head will still point at it, yet the node's next/prev will
contain the list poison values. When the next DMA request completes,
a kernel panic will occur when those poison values are dereferenced.

This makes the DMA driver more robust in the face of buggy clients.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-19 14:35:52 -08:00
Colin Cross
fe92a026e3 Merge branch 'tegra-arch' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound-2.6 into outside-for-next 2011-02-19 14:35:16 -08:00
Mike Rapoport
cca414b263 ARM: tegra: add TrimSlice board
Add basic support for CompuLab TrimSlice platform

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 18:36:51 -08:00
Colin Cross
535371c3fb ARM: tegra: Use writel_relaxed in tegra_init_cache
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:43 -08:00
Olof Johansson
f2b6133ffc ARM: tegra: add tegra_defconfig
Adding one single defconfig for the tegra family of boards, to over time
cover the superset of supported platform and drivers.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:42 -08:00
Colin Cross
5789fee934 ARM: tegra: dma: Fix critical data corruption bugs
Sometimes, due to high interrupt latency in the continuous mode
of DMA transfer, the half buffer complete interrupt is handled
after DMA has transferred the full buffer.  When this is detected,
stop DMA immediately and restart with the next buffer if the next
buffer is ready.

originally fixed by Victor(Weiguo) Pan <wpan@nvidia.com>

In place of using the simple spin_lock()/spi_unlock() in the
interrupt thread, using the spin_lock_irqsave() and
spin_unlock_irqrestore(). The lock is shared between the normal
process context and interrupt context.

originally fixed by Laxman Dewangan (ldewangan@nvidia.com)

The use of shadow registers caused memory corruption at physical
address 0 because the enable bit was not shadowed, and assuming it
needed to be set would enable an unconfigured dma block.  Most of the
register accesses don't need to know the previous state of the
registers, and the few places that do need to modify only a few bits
in the registers are the same ones that were sometimes incorrectly
setting the enable bit.  This patch convert tegra_dma_update_hardware
to set the entire register, and the other users to read-modify-write,
and drops the shadow registers completely.

Also fixes missing locking in tegra_dma_allocate_channel

Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:41 -08:00
Colin Cross
699fe145d6 ARM: tegra: Allow overriding arch_reset
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:41 -08:00
Colin Cross
1eb2ecf1d5 ARM: tegra: cpufreq: Disable cpufreq during suspend
On Tegra, calling clk_set_rate on the CPU clock may call into the
regulator API.  If the regulator driver that controls the CPU
voltage rail has been suspended, this can lead to attempted
communication with a hardware block that has already been turned
off.

Adds a SUSPEND_PREPARE notification hook to drop the frequency to
the lowest possible during suspend.

Also adds 216MHz (off of PLLP) as the lowest CPU frequency, which
allows PLLX to be turned off.

Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:40 -08:00
Gary King
537f5af0f6 ARM: tegra: iomap: Add missing devices
Adds gart, hdmi, avp, host1x, and pwm controllers to mach/iomap.h

Signed-off-by: Gary King <gking@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-10 17:50:23 -08:00
Colin Cross
26d902c0c6 ARM: tegra: irq: Implement retrigger
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 22:18:30 -08:00
Colin Cross
3524b70ef3 ARM: tegra: irq: Add support for suspend wake sources
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 22:18:21 -08:00
Colin Cross
093617851c ARM: tegra: timer: Add idle and suspend support to timers
Implement read_persistent_clock by reading the Tegra RTC
registers that stay running during suspend.

Save and restore the timer configuration register in
suspend.

Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 22:17:38 -08:00
Gary King
3c3895b4bf ARM: tegra: pinmux: Add missing drive pingroups and fix suspend
Adds missing drive pingroups, saves all drive pingroups in
suspend, and restores the pinmux registers in the proper order.

Signed-off-by: Gary King <gking@nvidia.com>
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:57:02 -08:00
Colin Cross
cea62c878d ARM: tegra: clock: Suspend fixes, and add new clocks
Save and restore pll and osc state during suspend
Add digital audio clocks
Update clk dev associations
Correct max clock frequencies
Add pll_p as additional cpu clock state
Add values to plld table
Fix register offset for sdmmc4 clock
Add blink timer to tegra2_clocks

Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:57:02 -08:00
Colin Cross
2ea67fd145 ARM: tegra: Add prototypes for subsystem suspend functions
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:57:01 -08:00
Colin Cross
538bd3cc19 ARM: tegra: irqs: Update irq list
Fixes typo in INT_CPU1_PMU_INTR (original fix from Will Deacon)
Adds board irqs

Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:57:01 -08:00
Colin Cross
ce1e326269 ARM: tegra: Add api to control internal powergating
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:57:00 -08:00
Colin Cross
d377eb0d95 ARM: tegra: Centralize macros to define debug uart base
Signed-off-by: Colin Cross <ccross@android.com>
2011-02-09 21:56:59 -08:00
Linus Torvalds
65d9055ea3 Merge master.kernel.org:/home/rmk/linux-2.6-arm
* master.kernel.org:/home/rmk/linux-2.6-arm:
  ALSA: AACI: allow writes to MAINCR to take effect
  ARM: Update mach-types
  ARM: 6652/1: ep93xx: correct the end address of the AC97 memory resource
  ARM: mxs/imx28: remove now unused clock lookup "fec.0"
  ARM: mxs: fix clock base address missing
  ARM: mxs: acknowledge gpio irq
  ARM: mach-imx/mach-mx25_3ds: Fix section type
  ARM: imx: Add VPR200 and MX51_3DS entries to uncompress.h
  ARM i.MX23: use correct register for setting the rate
  ARM i.MX23/28: remove secondary field from struct clk. It's unused
  ARM i.MX28: use correct register for setting the rate
  ARM i.MX28: fix bit operation
2011-02-07 15:20:11 -08:00
Linus Torvalds
eee4da2cef Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Fix hcall tracepoint recursion
  powerpc/numa: Fix bug in unmap_cpu_from_node
  powerpc/numa: Disable VPHN on dedicated processor partitions
  powerpc/numa: Add length when creating OF properties via VPHN
  powerpc/numa: Check for all VPHN changes
  powerpc/numa: Only use active VPHN count fields
  powerpc/pseries: Remove unnecessary variable initializations in numa.c
  powerpc/pseries: Fix brace placement in numa.c
  powerpc/pseries: Fix typo in VPHN comments
  powerpc: Fix some 6xx/7xxx CPU setup functions
  powerpc: Pass the right cpu_spec to ->setup_cpu() on 64-bit
  powerpc/book3e: Protect complex macro args in mmu-book3e.h
  powerpc: Fix pfn_valid() when memory starts at a non-zero address
2011-02-07 14:05:38 -08:00
Linus Torvalds
b8f049ae55 Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6
* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  arm: omap4: panda: remove usb_nop_xceiv_register(v1)
  OMAP1: Fix non-working LCD on OMAP310
  OMAP3: Devkit8000: Change lcd power pin
  omap1: remove duplicated #include
  arm: mach-omap2: mux: free allocated memory on error exit
  arm: mach-omap2: board-rm680: fix rm680_vemmc regulator constraints
  OMAP: PM: SmartReflex: Fix possible null pointer read access
  OMAP: PM: SmartReflex: Fix possible memory leak
  arm: mach-omap2: voltage: debugfs: fix memory leak
  OMAP3: PM: fix save secure RAM to restore MPU power state
  OMAP: PM: SmartReflex: Add missing IS_ERR test
2011-02-07 14:05:24 -08:00
Russell King
1f63b9546a Merge branch 'fixes' 2011-02-07 19:07:10 +00:00
Russell King
d8cff1365e Merge branch 'for-rmk' of git://git.pengutronix.de/git/imx/linux-2.6 into fixes 2011-02-07 15:15:41 +00:00
Russell King
4a683a2c5e ARM: Update mach-types
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-07 09:04:48 +00:00
H. Peter Anvin
d344e38b2c x86, nx: Mark the ACPI resume trampoline code as +x
We reserve lowmem for the things that need it, like the ACPI
wakeup code, way early to guarantee availability.  This happens
before we set up the proper pagetables, so set_memory_x() has no
effect.

Until we have a better solution, use an initcall to mark the
wakeup code executable.

Originally-by: Matthieu Castet <castet.matthieu@free.fr>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Matthias Hopf <mhopf@suse.de>
Cc: rjw@sisk.pl
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4D4F8019.2090104@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-07 09:07:13 +01:00
Anton Blanchard
57cdfdf829 powerpc: Fix hcall tracepoint recursion
Spinlocks on shared processor partitions use H_YIELD to notify the
hypervisor we are waiting on another virtual CPU. Unfortunately this means
the hcall tracepoints can recurse.

The patch below adds a percpu depth and checks it on both the entry and
exit hcall tracepoints.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@kernel.org
2011-02-07 13:06:08 +11:00
Anton Blanchard
429f4d8d20 powerpc/numa: Fix bug in unmap_cpu_from_node
When converting to the new cpumask code I screwed up:

-       if (cpu_isset(cpu, numa_cpumask_lookup_table[node])) {
-               cpu_clear(cpu, numa_cpumask_lookup_table[node]);
+       if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
+               cpumask_set_cpu(cpu, node_to_cpumask_map[node]);

This was introduced in commit 25863de07a (powerpc/cpumask: Convert NUMA code
to new cpumask API)

Fix it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:06:06 +11:00
Anton Blanchard
fe5cfd6355 powerpc/numa: Disable VPHN on dedicated processor partitions
There is no need to start up the timer and monitor topology changes on a
dedicated processor partition, so disable it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:06:04 +11:00
Anton Blanchard
c0e5e46f39 powerpc/numa: Add length when creating OF properties via VPHN
The rest of the NUMA code expects an OF associativity property with
the first cell containing the length. Without this fix all topology changes
cause us to misparse the property and put the cpu into node 0.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:06:03 +11:00
Anton Blanchard
d69043e806 powerpc/numa: Check for all VPHN changes
The hypervisor uses unsigned 1 byte counters to signal topology changes to
the OS. Since they can wrap we need to check for any difference, not just if
the hypervisor count is greater than the previous count.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:06:01 +11:00
Anton Blanchard
5de1669910 powerpc/numa: Only use active VPHN count fields
VPHN supports up to 8 distance fields but the number of entries in
ibm,associativity-reference-points signifies how many are in use.
Don't look at all the VPHN counts, only distance_ref_points_depth
worth.

Since we already cap our distance metrics at MAX_DISTANCE_REF_POINTS,
use that to size the VPHN arrays and add a BUILD_BUG_ON to avoid it growing
larger than the VPHN maximum of 8.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:05:59 +11:00
Jesse Larrew
cd9d6cc726 powerpc/pseries: Remove unnecessary variable initializations in numa.c
Remove unnecessary variable initializations in VPHN functions.

Signed-off-by: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 13:05:36 +11:00
Jesse Larrew
7639adaafb powerpc/pseries: Fix brace placement in numa.c
Fix brace placement in VPHN code.

Signed-off-by: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 12:58:23 +11:00
Jesse Larrew
bd03403ad5 powerpc/pseries: Fix typo in VPHN comments
Correct a spelling error in VPHN comments in numa.c.

Signed-off-by: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 12:58:21 +11:00
Benjamin Herrenschmidt
1f1936ff3f powerpc: Fix some 6xx/7xxx CPU setup functions
Some of those functions try to adjust the CPU features, for example
to remove NAP support on some revisions. However, they seem to use
r5 as an index into the CPU table entry, which might have been right
a long time ago but no longer is. r4 is the right register to use.

This probably caused some off behaviours on some PowerMac variants
using 750cx or 7455 processor revisions.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@kernel.org
2011-02-07 12:57:11 +11:00
Benjamin Herrenschmidt
af9eef3c7b powerpc: Pass the right cpu_spec to ->setup_cpu() on 64-bit
When calling setup_cpu() on 64-bit, we pass a pointer to the
cputable entry we have found. This used to be fine when cur_cpu_spec
was a pointer to that entry, but nowadays, we copy the entry into
a separate variable, and we do so before we call the setup_cpu()
callback. That means that any attempt by that callback at patching
the CPU table entry (to adjust CPU features for example) will patch
the wrong table.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 12:47:57 +11:00
Scott Wood
b51cbd41a3 powerpc/book3e: Protect complex macro args in mmu-book3e.h
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 12:47:56 +11:00
Scott Wood
81c386cc7f powerpc: Fix pfn_valid() when memory starts at a non-zero address
max_mapnr is a pfn, not an index innto mem_map[].  So don't add
ARCH_PFN_OFFSET a second time.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-02-07 12:47:56 +11:00
Linus Torvalds
8dbdea8444 Merge branch 'ixp4xx' of git://git.kernel.org/pub/scm/linux/kernel/git/chris/linux-2.6
* 'ixp4xx' of git://git.kernel.org/pub/scm/linux/kernel/git/chris/linux-2.6:
  arm/ixp4xx: Rename FREQ macro to avoid collisions
  IXP4xx: Fix qmgr_release_queue() flushing unexpected queue entries.
2011-02-06 12:05:58 -08:00
Linus Torvalds
43a723286f Merge branch 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  m32r: Fixup last __do_IRQ leftover
  genirq: Add missing status flags to modification mask
2011-02-06 12:04:49 -08:00
Linus Torvalds
07675f484b Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86-32: Make sure the stack is set up before we use it
  x86, mtrr: Avoid MTRR reprogramming on BP during boot on UP platforms
  x86, nx: Don't force pages RW when setting NX bits
2011-02-06 12:03:10 -08:00
Ben Hutchings
e66a022a80 arm/ixp4xx: Rename FREQ macro to avoid collisions
FREQ is a ridiculously short name for a platform-specific macro in a
generic header, and it now conflicts with an enumeration in the
gspca/ov519 driver.

Also delete conditional reference to ixp4xx_get_board_tick_rate()
which is not defined anywhere.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2011-02-06 16:49:48 +01:00
Krzysztof Hałasa
3c3a3b4c12 IXP4xx: Fix qmgr_release_queue() flushing unexpected queue entries.
Queues should be empty when released, if not, there is a safety valve.
Make sure the queue is usable after it triggers.

Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>
2011-02-06 16:49:48 +01:00
Thomas Gleixner
a9fe8d5fd5 m32r: Fixup last __do_IRQ leftover
Somehow I managed to miss the last __do_IRQ caller when I cleanup the
remaining users. m32r is fully converted to the generic irq layer, but
I managed to not commit the conversion of __do_IRQ() to
generic_handle_irq() after compile testing the quilt series :(

Pointed-out-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Paul Mundt <lethal@linux-sh.org>
2011-02-05 21:46:35 +01:00
Mika Westerberg
ec11594fbd ARM: 6652/1: ep93xx: correct the end address of the AC97 memory resource
The last register is at offset 0xa8 making the resource end to be 0xac - 1
instead of 0xb0 - 1.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-02-05 09:50:44 +00:00
H. Peter Anvin
11d4c3f9b6 x86-32: Make sure the stack is set up before we use it
Since checkin ebba638ae7 we call
verify_cpu even in 32-bit mode.  Unfortunately, calling a function
means using the stack, and the stack pointer was not initialized in
the 32-bit setup code!  This code initializes the stack pointer, and
simplifies the interface slightly since it is easier to rely on just a
pointer value rather than a descriptor; we need to have different
values for the segment register anyway.

This retains start_stack as a virtual address, even though a physical
address would be more convenient for 32 bits; the 64-bit code wants
the other way around...

Reported-by: Matthieu Castet <castet.matthieu@free.fr>
LKML-Reference: <4D41E86D.8060205@free.fr>
Tested-by: Kees Cook <kees.cook@canonical.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2011-02-04 22:27:28 -08:00
Suresh Siddha
831d52bc15 x86, mm: avoid possible bogus tlb entries by clearing prev mm_cpumask after switching mm
Clearing the cpu in prev's mm_cpumask early will avoid the flush tlb
IPI's while the cr3 is still pointing to the prev mm.  And this window
can lead to the possibility of bogus TLB fills resulting in strange
failures.  One such problematic scenario is mentioned below.

 T1. CPU-1 is context switching from mm1 to mm2 context and got a NMI
     etc between the point of clearing the cpu from the mm_cpumask(mm1)
     and before reloading the cr3 with the new mm2.

 T2. CPU-2 is tearing down a specific vma for mm1 and will proceed with
     flushing the TLB for mm1.  It doesn't send the flush TLB to CPU-1
     as it doesn't see that cpu listed in the mm_cpumask(mm1).

 T3. After the TLB flush is complete, CPU-2 goes ahead and frees the
     page-table pages associated with the removed vma mapping.

 T4. CPU-2 now allocates those freed page-table pages for something
     else.

 T5. As the CR3 and TLB caches for mm1 is still active on CPU-1, CPU-1
     can potentially speculate and walk through the page-table caches
     and can insert new TLB entries.  As the page-table pages are
     already freed and being used on CPU-2, this page walk can
     potentially insert a bogus global TLB entry depending on the
     (random) contents of the page that is being used on CPU-2.

 T6. This bogus TLB entry being global will be active across future CR3
     changes and can result in weird memory corruption etc.

To avoid this issue, for the prev mm that is handing over the cpu to
another mm, clear the cpu from the mm_cpumask(prev) after the cr3 is
changed.

Marking it for -stable, though we haven't seen any reported failure that
can be attributed to this.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org	[v2.6.32+]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-03 13:32:39 -08:00
Linus Torvalds
eb487ab4d5 Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf: Fix reading in perf_event_read()
  watchdog: Don't change watchdog state on read of sysctl
  watchdog: Fix sysctl consistency
  watchdog: Fix broken nowatchdog logic
  perf: Fix Pentium4 raw event validation
  perf: Fix alloc_callchain_buffers()
2011-02-03 08:52:05 -08:00
Suresh Siddha
f7448548a9 x86, mtrr: Avoid MTRR reprogramming on BP during boot on UP platforms
Markus Kohn ran into a hard hang regression on an acer aspire
1310, when acpi is enabled. git bisect showed the following
commit as the bad one that introduced the boot regression.

	commit d0af9eed5a
	Author: Suresh Siddha <suresh.b.siddha@intel.com>
	Date:   Wed Aug 19 18:05:36 2009 -0700

	    x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init

Because of the UP configuration of that platform,
native_smp_prepare_cpus() bailed out (in smp_sanity_check())
before doing the set_mtrr_aps_delayed_init()

Further down the boot path, native_smp_cpus_done() will call the
delayed MTRR initialization for the AP's (mtrr_aps_init()) with
mtrr_aps_delayed_init not set. This resulted in the boot
processor reprogramming its MTRR's to the values seen during the
start of the OS boot. While this is not needed ideally, this
shouldn't have caused any side-effects. This is because the
reprogramming of MTRR's (set_mtrr_state() that gets called via
set_mtrr()) will check if the live register contents are
different from what is being asked to write and will do the actual
write only if they are different.

BP's mtrr state is read during the start of the OS boot and
typically nothing would have changed when we ask to reprogram it
on BP again because of the above scenario on an UP platform. So
on a normal UP platform no reprogramming of BP MTRR MSR's
happens and all is well.

However, on this platform, bios seems to be modifying the fixed
mtrr range registers between the start of OS boot and when we
double check the live registers for reprogramming BP MTRR
registers. And as the live registers are modified, we end up
reprogramming the MTRR's to the state seen during the start of
the OS boot.

During ACPI initialization, something in the bios (probably smi
handler?) don't like this fact and results in a hard lockup.

We didn't see this boot hang issue on this platform before the
commit d0af9eed5a, because only
the AP's (if any) will program its MTRR's to the value that BP
had at the start of the OS boot.

Fix this issue by checking mtrr_aps_delayed_init before
continuing further in the mtrr_aps_init(). Now, only AP's (if
any) will program its MTRR's to the BP values during boot.

Addresses https://bugzilla.novell.com/show_bug.cgi?id=623393

  [ By the way, this behavior of the bios modifying MTRR's after the start
    of the OS boot is not common and the kernel is not prepared to
    handle this situation well. Irrespective of this issue, during
    suspend/resume, linux kernel will try to reprogram the BP's MTRR values
    to the values seen during the start of the OS boot. So suspend/resume might
    be already broken on this platform for all linux kernel versions. ]

Reported-and-bisected-by: Markus Kohn <jabber@gmx.org>
Tested-by: Markus Kohn <jabber@gmx.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Thomas Renninger <trenn@novell.com>
Cc: Rafael Wysocki <rjw@novell.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: stable@kernel.org # [v2.6.32+]
LKML-Reference: <1296694975.4418.402.camel@sbsiddha-MOBL3.sc.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-03 12:10:38 +01:00
Linus Torvalds
b8ef289daa Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
  [S390] reset default for CONFIG_CHSC_SCH
  [S390] qdio: prevent compile warning under CONFIG_32BIT
  [S390] use asm-generic/cacheflush.h
  [S390] tlb: fix build error caused by THP
  [S390] missing sacf in uaccess
  [S390] pgtable_list corruption
  [S390] dasd: prevent panic with unresumed devices
2011-02-02 17:51:31 -08:00