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Merge tag 'v4.4-rc2' into drm-intel-next-queued
Linux 4.4-rc2
Backmerge to get at
commit 1b0e3a049e
Author: Imre Deak <imre.deak@intel.com>
Date: Thu Nov 5 23:04:11 2015 +0200
drm/i915/skl: disable display side power well support for now
so that we can proplery re-eanble skl power wells in -next.
Conflicts are just adjacent lines changed, except for intel_fbdev.c
where we need to interleave the changs. Nothing nefarious.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Standardize on bool instead of an inconsistent mixture of u8 and plain 'int'.
Also use u32 or 'unsigned int' instead of 'unsigned long' when a 32-bit type
suffices, generating slightly better code on x86-64.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/5624E3A002000078000AC49A@prv-mh.provo.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull drm updates from Dave Airlie:
"This is the main drm pull request for v4.2.
I've one other new driver from freescale on my radar, it's been posted
and reviewed, I'd just like to get someone to give it a last look, so
maybe I'll send it or maybe I'll leave it.
There is no major nouveau changes in here, Ben was working on
something big, and we agreed it was a bit late, there wasn't anything
else he considered urgent to merge.
There might be another msm pull for some bits that are waiting on
arm-soc, I'll see how we time it.
This touches some "of" stuff, acks are in place except for the fixes
to the build in various configs,t hat I just applied.
Summary:
New drivers:
- virtio-gpu:
KMS only pieces of driver for virtio-gpu in qemu.
This is just the first part of this driver, enough to run
unaccelerated userspace on. As qemu merges more we'll start
adding the 3D features for the virgl 3d work.
- amdgpu:
a new driver from AMD to driver their newer GPUs. (VI+)
It contains a new cleaner userspace API, and is a clean
break from radeon moving forward, that AMD are going to
concentrate on. It also contains a set of register headers
auto generated from AMD internal database.
core:
- atomic modesetting API completed, enabled by default now.
- Add support for mode_id blob to atomic ioctl to complete interface.
- bunch of Displayport MST fixes
- lots of misc fixes.
panel:
- new simple panels
- fix some long-standing build issues with bridge drivers
radeon:
- VCE1 support
- add a GPU reset counter for userspace
- lots of fixes.
amdkfd:
- H/W debugger support module
- static user-mode queues
- support killing all the waves when a process terminates
- use standard DECLARE_BITMAP
i915:
- Add Broxton support
- S3, rotation support for Skylake
- RPS booting tuning
- CPT modeset sequence fixes
- ns2501 dither support
- enable cmd parser on haswell
- cdclk handling fixes
- gen8 dynamic pte allocation
- lots of atomic conversion work
exynos:
- Add atomic modesetting support
- Add iommu support
- Consolidate drm driver initialization
- and MIC, DECON and MIPI-DSI support for exynos5433
omapdrm:
- atomic modesetting support (fixes lots of things in rewrite)
tegra:
- DP aux transaction fixes
- iommu support fix
msm:
- adreno a306 support
- various dsi bits
- various 64-bit fixes
- NV12MT support
rcar-du:
- atomic and misc fixes
sti:
- fix HDMI timing complaince
tilcdc:
- use drm component API to access tda998x driver
- fix module unloading
qxl:
- stability fixes"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (872 commits)
drm/nouveau: Pause between setting gpu to D3hot and cutting the power
drm/dp/mst: close deadlock in connector destruction.
drm: Always enable atomic API
drm/vgem: Set unique to "vgem"
of: fix a build error to of_graph_get_endpoint_by_regs function
drm/dp/mst: take lock around looking up the branch device on hpd irq
drm/dp/mst: make sure mst_primary mstb is valid in work function
of: add EXPORT_SYMBOL for of_graph_get_endpoint_by_regs
ARM: dts: rename the clock of MIPI DSI 'pll_clk' to 'sclk_mipi'
drm/atomic: Don't set crtc_state->enable manually
drm/exynos: dsi: do not set TE GPIO direction by input
drm/exynos: dsi: add support for MIC driver as a bridge
drm/exynos: dsi: add support for Exynos5433
drm/exynos: dsi: make use of array for clock access
drm/exynos: dsi: make use of driver data for static values
drm/exynos: dsi: add macros for register access
drm/exynos: dsi: rename pll_clk to sclk_clk
drm/exynos: mic: add MIC driver
of: add helper for getting endpoint node of specific identifiers
drm/exynos: add Exynos5433 decon driver
...
This question has been asked many times, and finally I found the
official document which explains the problem of HPET on Baytrail,
that it will halt in deep idle states.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: john.stultz@linaro.org
Cc: len.brown@intel.com
Cc: matthew.lee@intel.com
Link: http://lkml.kernel.org/r/1434361201-31743-1-git-send-email-feng.tang@intel.com
[ Prettified things a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
v2: Rebase on top of the early-quirks rework from Ville.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com> (v1)
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Skylake introduces new stolen memory sizes starting at 0xf0 (4MB) and
growing by 4MB increments from there.
v2: Rebase on top of the early-quirk changes from Ville.
v3: Rebase on top of the PCI_IDS/IDS macro rename
Reviewed-by: Thomas Wood <thomas.wood@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Merge drm-fixes into drm-next.
Both i915 and radeon need this done for later patches.
Conflicts:
drivers/gpu/drm/drm_crtc_helper.c
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/i915_gem_execbuffer.c
drivers/gpu/drm/i915/i915_gem_gtt.c
gen8_stolen_size() is missing __init, so add it.
Also all the intel_stolen_funcs structures can be marked
__initconst.
intel_stolen_ids[] can also be made const if we replace the
__initdata with __initconst.
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
CHV uses the same bits as SNB/VLV to code the Graphics Mode Select field
(GFX stolen memory size) with the addition of finer granularity modes:
4MB increments from 0x11 (8MB) to 0x1d.
Values strictly above 0x1d are either reserved or not supported.
v2: 4MB increments, not 8MB. 32MB has been omitted from the list of new
values (Ville Syrjälä)
v3: Also correctly interpret GGMS (GTT Graphics Memory Size) (Ville
Syrjälä)
v4: Don't assign a value that needs 20bits or more to a u16 (Rafael
Barbalho)
[vsyrjala: v5: Split from i915 changes and add chv_stolen_funcs]
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Rafael Barbalho <rafael.barbalho@intel.com>
Tested-by: Rafael Barbalho <rafael.barbalho@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
HPET on current Baytrail platform has accuracy problem to be
used as reliable clocksource/clockevent, so add a early quirk to
disable it.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1398327498-13163-2-git-send-email-feng.tang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Have the KB(),MB(),GB() macros produce unsigned longs to avoid
unintended sign extension issues with the gen2 memory size
detection.
What happens is first the uint8_t returned by
read_pci_config_byte() gets promoted to an int which gets
multiplied by another int from the MB() macro, and finally the
result gets sign extended to size_t.
Although this shouldn't be a problem in practice as all affected
gen2 platforms are 32bit AFAIK, so size_t will be 32 bits.
Reported-by: Bjorn Helgaas <bhelgaas@google.com>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1397382303-17525-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pullx86 core platform updates from Peter Anvin:
"This is the x86/platform branch with the objectionable IOSF patches
removed.
What is left is proper memory handling for Intel GPUs, and a change to
the Calgary IOMMU code which will be required to make kexec work
sanely on those platforms after some upcoming kexec changes"
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, calgary: Use 8M TCE table size by default
x86/gpu: Print the Intel graphics stolen memory range
x86/gpu: Add Intel graphics stolen memory quirk for gen2 platforms
x86/gpu: Add vfunc for Intel graphics stolen memory base address
Commit 03bbcb2e7e (iommu/vt-d: add quirk for broken interrupt
remapping on 55XX chipsets) properly disables irq remapping on the
5500/5520 chipsets that don't correctly perform that feature.
However, when I wrote it, I followed the errata sheet linked in that
commit too closely, and explicitly tied the activation of the quirk to
revision 0x13 of the chip, under the assumption that earlier revisions
were not in the field. Recently a system was reported to be suffering
from this remap bug and the quirk hadn't triggered, because the
revision id register read at a lower value that 0x13, so the quirk
test failed improperly. Given this, it seems only prudent to adjust
this quirk so that any revision less than 0x13 has the quirk asserted.
[ tglx: Removed the 0x12 comparison of pci id 3405 as this is covered
by the <= 0x13 check already ]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1394649873-14913-1-git-send-email-nhorman@tuxdriver.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There isn't an explicit stolen memory base register on gen2.
Some old comment in the i915 code suggests we should get it via
max_low_pfn_mapped, but that's clearly a bad idea on my MGM.
The e820 map in said machine looks like this:
BIOS-e820: [mem 0x0000000000000000-0x000000000009f7ff] usable
BIOS-e820: [mem 0x000000000009f800-0x000000000009ffff] reserved
BIOS-e820: [mem 0x00000000000ce000-0x00000000000cffff] reserved
BIOS-e820: [mem 0x00000000000dc000-0x00000000000fffff] reserved
BIOS-e820: [mem 0x0000000000100000-0x000000001f6effff] usable
BIOS-e820: [mem 0x000000001f6f0000-0x000000001f6f7fff] ACPI data
BIOS-e820: [mem 0x000000001f6f8000-0x000000001f6fffff] ACPI NVS
BIOS-e820: [mem 0x000000001f700000-0x000000001fffffff] reserved
BIOS-e820: [mem 0x00000000fec10000-0x00000000fec1ffff] reserved
BIOS-e820: [mem 0x00000000ffb00000-0x00000000ffbfffff] reserved
BIOS-e820: [mem 0x00000000fff00000-0x00000000ffffffff] reserved
That makes max_low_pfn_mapped = 1f6f0000, so assuming our stolen
memory would start there would place it on top of some ACPI
memory regions. So not a good idea as already stated.
The 9MB region after the ACPI regions at 0x1f700000 however
looks promising given that the macine reports the stolen memory
size to be 8MB. Looking at the PGTBL_CTL register, the GTT
entries are at offset 0x1fee00000, and given that the GTT
entries occupy 128KB, it looks like the stolen memory could
start at 0x1f700000 and the GTT entries would occupy the last
128KB of the stolen memory.
After some more digging through chipset documentation, I've
determined the BIOS first allocates space for something called
TSEG (something to do with SMM) from the top of memory, and then
it allocates the graphics stolen memory below that. Accordind to
the chipset documentation TSEG has a fixed size of 1MB on 855.
So that explains the top 1MB in the e820 region. And it also
confirms that the GTT entries are in fact at the end of the the
stolen memory region.
Derive the stolen memory base address on gen2 the same as the
BIOS does (TOM-TSEG_SIZE-stolen_size). There are a few
differences between the registers on various gen2 chipsets, so a
few different codepaths are required.
865G is again bit more special since it seems to support enough
memory to hit 4GB address space issues. This means the PCI
allocations will also affect the location of the stolen memory.
Fortunately there appears to be the TOUD register which may give
us the correct answer directly. But the chipset docs are a bit
unclear, so I'm not 100% sure that the graphics stolen memory is
always the last thing the BIOS steals. Someone would need to
verify it on a real system.
I tested this on the my 830 and 855 machines, and so far
everything looks peachy.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1391628540-23072-3-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For gen2 devices we're going to need another way to determine
the stolen memory base address. Make that into a vfunc as well.
Also drop the bogus inline keyword from gen8_stolen_size().
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Link: http://lkml.kernel.org/r/1391628540-23072-2-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We've always been able to use either method on VLV, but it appears more
recent BIOSes only support the gen6 method, so switch over to that.
References: https://bugs.freedesktop.org/show_bug.cgi?id=71370
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
All the BARs have the ability to grow.
v2: Pulled out the simulator workaround to a separate patch.
Rebased.
v3: Rebase onto latest vlv patches from Jesse.
v4: Rebased on top of the early stolen quirk patch from Jesse.
v5: Use the new macro names.
s/INTEL_BDW_PCI_IDS_D/INTEL_BDW_D_IDS
s/INTEL_BDW_PCI_IDS_M/INTEL_BDW_M_IDS
It's Jesse's fault for not following the convention I originally set.
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Systems with Intel graphics controllers set aside memory exclusively for
gfx driver use. This memory is not always marked in the E820 as
reserved or as RAM, and so is subject to overlap from E820 manipulation
later in the boot process. On some systems, MMIO space is allocated on
top, despite the efforts of the "RAM buffer" approach, which simply
rounds memory boundaries up to 64M to try to catch space that may decode
as RAM and so is not suitable for MMIO.
v2: use read_pci_config for 32 bit reads instead of adding a new one
(Chris)
add gen6 stolen size function (Chris)
v3: use a function pointer (Chris)
drop gen2 bits (Daniel)
v4: call e820_sanitize_map after adding the region
v5: fixup comments (Peter)
simplify loop (Chris)
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66726
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66844
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Recently we added an early quirk to detect 5500/5520 chipsets
with early revisions that had problems with irq draining with
interrupt remapping enabled:
commit 03bbcb2e7e
Author: Neil Horman <nhorman@tuxdriver.com>
Date: Tue Apr 16 16:38:32 2013 -0400
iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets
It turns out this same problem is present in the intel X58
chipset as well. See errata 69 here:
http://www.intel.com/content/www/us/en/chipsets/x58-express-specification-update.html
This patch extends the pci early quirk so that the chip
devices/revisions specified in the above update are also covered
in the same way:
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Donald Dutile <ddutile@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Malcolm Crossley <malcolm.crossley@citrix.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1374059639-8631-1-git-send-email-nhorman@tuxdriver.com
[ Small edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A few years back intel published a spec update:
http://www.intel.com/content/dam/doc/specification-update/5520-and-5500-chipset-ioh-specification-update.pdf
For the 5520 and 5500 chipsets which contained an errata (specificially errata
53), which noted that these chipsets can't properly do interrupt remapping, and
as a result the recommend that interrupt remapping be disabled in bios. While
many vendors have a bios update to do exactly that, not all do, and of course
not all users update their bios to a level that corrects the problem. As a
result, occasionally interrupts can arrive at a cpu even after affinity for that
interrupt has be moved, leading to lost or spurrious interrupts (usually
characterized by the message:
kernel: do_IRQ: 7.71 No irq handler for vector (irq -1)
There have been several incidents recently of people seeing this error, and
investigation has shown that they have system for which their BIOS level is such
that this feature was not properly turned off. As such, it would be good to
give them a reminder that their systems are vulnurable to this problem. For
details of those that reported the problem, please see:
https://bugzilla.redhat.com/show_bug.cgi?id=887006
[ Joerg: Removed CONFIG_IRQ_REMAP ifdef from early-quirks.c ]
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Prarit Bhargava <prarit@redhat.com>
CC: Don Zickus <dzickus@redhat.com>
CC: Don Dutile <ddutile@redhat.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Asit Mallick <asit.k.mallick@intel.com>
CC: David Woodhouse <dwmw2@infradead.org>
CC: linux-pci@vger.kernel.org
CC: Joerg Roedel <joro@8bytes.org>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Arkadiusz Miśkiewicz <arekm@maven.pl>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
Commit 7f74f8f28a
(x86 quirk: Fix polarity for IRQ0 pin2 override on SB800
systems) introduced a regression. It removed some SB600 specific
code to determine the revision ID without adapting a
corresponding revision ID check for SB600.
See this mail thread:
http://marc.info/?l=linux-kernel&m=129980296006380&w=2
This patch adapts the corresponding check to cover all SB600
revisions.
Tested-by: Wang Lei <f3d27b@gmail.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@kernel.org # 38.x, 37.x, 32.x
LKML-Reference: <20110315143137.GD29499@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On some SB800 systems polarity for IOAPIC pin2 is wrongly
specified as low active by BIOS. This caused system hangs after
resume from S3 when HPET was used in one-shot mode on such
systems because a timer interrupt was missed (HPET signal is
high active).
For more details see:
http://marc.info/?l=linux-kernel&m=129623757413868
Tested-by: Manoj Iyer <manoj.iyer@canonical.com>
Tested-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: stable@kernel.org # 37.x, 32.x
LKML-Reference: <20110224145346.GD3658@alberich.amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This more or less reverts commits 08be979 (x86: Force HPET
readback_cmp for all ATI chipsets) and 30a564be (x86, hpet: Restrict
read back to affected ATI chipsets) to the status of commit 8da854c
(x86, hpet: Erratum workaround for read after write of HPET
comparator).
The delta to commit 8da854c is mostly comments and the change from
WARN_ONCE to printk_once as we know the call path of this function
already.
This needs really in depth explanation:
First of all the HPET design is a complete failure. Having a counter
compare register which generates an interrupt on matching values
forces the software to do at least one superfluous readback of the
counter register.
While it is nice in theory to program "absolute" time events it is
practically useless because the timer runs at some absurd frequency
which can never be matched to real world units. So we are forced to
calculate a relative delta and this forces a readout of the actual
counter value, adding the delta and programming the compare
register. When the delta is small enough we run into the danger that
we program a compare value which is already in the past. Due to the
compare for equal nature of HPET we need to read back the counter
value after writing the compare rehgister (btw. this is necessary for
absolute timeouts as well) to make sure that we did not miss the timer
event. We try to work around that by setting the minimum delta to a
value which is larger than the theoretical time which elapses between
the counter readout and the compare register write, but that's only
true in theory. A NMI or SMI which hits between the readout and the
write can easily push us beyond that limit. This would result in
waiting for the next HPET timer interrupt until the 32bit wraparound
of the counter happens which takes about 306 seconds.
So we designed the next event function to look like:
match = read_cnt() + delta;
write_compare_ref(match);
return read_cnt() < match ? 0 : -ETIME;
At some point we got into trouble with certain ATI chipsets. Even the
above "safe" procedure failed. The reason was that the write to the
compare register was delayed probably for performance reasons. The
theory was that they wanted to avoid the synchronization of the write
with the HPET clock, which is understandable. So the write does not
hit the compare register directly instead it goes to some intermediate
register which is copied to the real compare register in sync with the
HPET clock. That opens another window for hitting the dreaded "wait
for a wraparound" problem.
To work around that "optimization" we added a read back of the compare
register which either enforced the update of the just written value or
just delayed the readout of the counter enough to avoid the issue. We
unfortunately never got any affirmative info from ATI/AMD about this.
One thing is sure, that we nuked the performance "optimization" that
way completely and I'm pretty sure that the result is worse than
before some HW folks came up with those.
Just for paranoia reasons I added a check whether the read back
compare register value was the same as the value we wrote right
before. That paranoia check triggered a couple of years after it was
added on an Intel ICH9 chipset. Venki added a workaround (commit
8da854c) which was reading the compare register twice when the first
check failed. We considered this to be a penalty in general and
restricted the readback (thus the wasted CPU cycles) to the known to
be affected ATI chipsets.
This turned out to be a utterly wrong decision. 2.6.35 testers
experienced massive problems and finally one of them bisected it down
to commit 30a564be which spured some further investigation.
Finally we got confirmation that the write to the compare register can
be delayed by up to two HPET clock cycles which explains the problems
nicely. All we can do about this is to go back to Venki's initial
workaround in a slightly modified version.
Just for the record I need to say, that all of this could have been
avoided if hardware designers and of course the HPET committee would
have thought about the consequences for a split second. It's out of my
comprehension why designing a working timer is so hard. There are two
ways to achieve it:
1) Use a counter wrap around aware compare_reg <= counter_reg
implementation instead of the easy compare_reg == counter_reg
Downsides:
- It needs more silicon.
- It needs a readout of the counter to apply a relative
timeout. This is necessary as the counter does not run in
any useful (and adjustable) frequency and there is no
guarantee that the counter which is used for timer events is
the same which is used for reading the actual time (and
therefor for calculating the delta)
Upsides:
- None
2) Use a simple down counter for relative timer events
Downsides:
- Absolute timeouts are not possible, which is not a problem
at all in the context of an OS and the expected
max. latencies/jitter (also see Downsides of #1)
Upsides:
- It needs less or equal silicon.
- It works ALWAYS
- It is way faster than a compare register based solution (One
write versus one write plus at least one and up to four
reads)
I would not be so grumpy about all of this, if I would not have been
ignored for many years when pointing out these flaws to various
hardware folks. I really hate timers (at least those which seem to be
designed by janitors).
Though finally we got a reasonable explanation plus a solution and I
want to thank all the folks involved in chasing it down and providing
valuable input to this.
Bisected-by: Nix <nix@esperi.org.uk>
Reported-by: Artur Skawina <art.08.09@gmail.com>
Reported-by: Damien Wyart <damien.wyart@free.fr>
Reported-by: John Drescher <drescherjm@gmail.com>
Cc: Venkatesh Pallipadi <venki@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: stable@kernel.org
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The ACPI/X86_IO_ACPI ifdef isn't necessary at this point,
because it is checked in an outer ifdef level already and has no
effect here.
Cleanup only, no functional effect.
Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: vamos-dev@i4.informatik.uni-erlangen.de
LKML-Reference: <d4376e6d79b8dc0f89a4b3ce4a880904a7b93ead.1283782701.git.qy03fugy@stud.informatik.uni-erlangen.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
commit 30a564be (x86, hpet: Restrict read back to affected ATI
chipset) restricted the workaround for the HPET bug to SMX00
chipsets. This was reasonable as those were the only ones against
which we ever got a bug report.
Stephan Wolf reported now that this patch breaks his IXP400 based
machine. Though it's confirmed to work on other IXP400 based systems.
To error out on the safe side, we force the HPET readback workaround
for all ATI SMbus class chipsets.
Reported-by: Stephan Wolf <stephan@letzte-bankreihe.de>
LKML-Reference: <alpine.LFD.2.00.1007142134140.3321@localhost.localdomain>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Stephan Wolf <stephan@letzte-bankreihe.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Impact: cleanup
this warning:
arch/x86/kernel/early-quirks.c:99: warning: ‘ati_ixp4x0_rev’ defined but not used
triggers because ati_ixp4x0_rev() is only used in the
ACPI && X86_IO_APIC case.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We found a situation on Linus' machine that the Nvidia timer quirk hit on
a Intel chipset system. The problem is that the system has a fancy Nvidia
card with an own PCI bridge, and the early-quirks code looking for any
NVidia bridge triggered on it incorrectly. This didn't lead a boot
failure by luck, but the timer routing code selecting the wrong timer
first and some ugly messages. It might lead to real problems on other
systems.
I checked all the devices which are currently checked for by early_quirks
and it turns out they are all located in the root bus zero.
So change the early-quirks loop to only scan bus 0. This incidently also
saves quite some unnecessary scanning work, because early_quirks doesn't
go through all the non root busses.
The graphics card is not on bus 0, so it is not matched anymore.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit e51af66308, which was
wrongly hoovered up and submitted about a month after a better fix had
already been merged.
The better fix is commit cbda1ba898
("PCI/iommu: blacklist DMAR on Intel G31/G33 chipsets"), where we do
this blacklisting based on the DMI identification for the offending
motherboard, since sometimes this chipset (or at least a chipset with
the same PCI ID) apparently _does_ actually have an IOMMU.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On some more HP laptops BIOS reports an IRQ0 override
but the SB600 chipset is configured such that timer
interrupts go to INT0 of IOAPIC.
Check IRQ0 routing and if it is routed to INT0 of IOAPIC skip the
timer override.
http://bugzilla.kernel.org/show_bug.cgi?id=11715http://bugzilla.kernel.org/show_bug.cgi?id=11516
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
On some HP nx6... laptops (e.g. nx6325) BIOS reports an IRQ0 override
but the SB450 chipset is configured such that timer interrupts goe to
INT0 of IOAPIC.
Check IRQ0 routing and if it is routed to INT0 of IOAPIC skip the
timer override.
[ This more generic PCI ID based quirk should alleviate the need for
dmi_ignore_irq0_timer_override DMI quirks. ]
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: "Maciej W. Rozycki" <macro@linux-mips.org>
Tested-by: Dmitry Torokhov <dtor@mail.ru>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some BIOSes (the Intel DG33BU, for example) wrongly claim to have DMAR
when they don't. Avoid the resulting crashes when it doesn't work as
expected.
I'd still be grateful if someone could test it on a DG33BU with the old
BIOS though, since I've killed mine. I tested the DMI version, but not
this one.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits)
Revert "x86/PCI: ACPI based PCI gap calculation"
PCI: remove unnecessary volatile in PCIe hotplug struct controller
x86/PCI: ACPI based PCI gap calculation
PCI: include linux/pm_wakeup.h for device_set_wakeup_capable
PCI PM: Fix pci_prepare_to_sleep
x86/PCI: Fix PCI config space for domains > 0
Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n
PCI: Simplify PCI device PM code
PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep
PCI ACPI: Rework PCI handling of wake-up
ACPI: Introduce new device wakeup flag 'prepared'
ACPI: Introduce acpi_device_sleep_wake function
PCI: rework pci_set_power_state function to call platform first
PCI: Introduce platform_pci_power_manageable function
ACPI: Introduce acpi_bus_power_manageable function
PCI: make pci_name use dev_name
PCI: handle pci_name() being const
PCI: add stub for pci_set_consistent_dma_mask()
PCI: remove unused arch pcibios_update_resource() functions
PCI: fix pci_setup_device()'s sprinting into a const buffer
...
Fixed up conflicts in various files (arch/x86/kernel/setup_64.c,
arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c,
drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86
and ACPI updates manually.
gart.h has only GART-specific stuff. Only GART code needs it. Other
IOMMU stuff should include iommu.h instead of gart.h.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove the "disable_8254_timer" and "enable_8254_timer" kernel
parameters. Now that AEOI acknowledgements are no longer needed for
correct timer operation, the 8259A can be kept disabled unconditionally
unless interrupts, either timer or watchdog ones, are actually passed
through it.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On x86, we do early PCI probing to apply some quirks for chipset bugs.
However, in a recent cleanup (7bcbc78dea) a
thinko was introduced that causes us to probe all subfunctions of even single
function devices (a function was factored out of an inner loop and a "break"
became a "return"). Fix that up by making check_dev_quirk() return a value so
we can keep the factored code intact.
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Fix following warnings:
WARNING: arch/x86/kernel/built-in.o(.text+0x139e1): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x139f5): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x13a0c): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x13a12): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x13a1a): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x13a36): Section mismatch: reference to .init.data:early_qrk in 'check_dev_quirk'
WARNING: arch/x86/kernel/built-in.o(.text+0x13a42): Section mismatch: reference to .init.data:
Warning was caused by access to the __initdata annotated variable
from the non-annotated static function check_dev_quirk().
check_dev_quirk() were only used from a function annotated
__init so add __init annotation to check_dev_quirk() to fix it.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Recently a kdump bug was discovered in which a system would hang inside
calibrate_delay during the booting of the kdump kernel. This was caused
by the fact that the jiffies counter was not being incremented during
timer calibration. The root cause of this problem was found to be a
bios misconfiguration of the hypertransport bus. On system affected by
this hang, the bios had assigned APIC ids which used extended apic bits
(more than the nominal 4 bit ids's), but failed to configure bit 17 of
the hypertransport transaction config register, which indicated that the
mask for the destination field of interrupt packets accross the ht bus
(see section 3.3.9 of
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF).
If a crash occurs on a cpu with an APIC id that extends beyond 4 bits,
it will not recieve interrupts during the kdump kernel boot, and this
hang will be the result. The fix is to add this patch, whcih add an
early pci quirk check, to forcibly enable this bit in the httcfg
register. This enables all cpus on a system to receive interrupts, and
allows kdump kernel bootup to procede normally.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch renames the 4 symbols iommu_hole_init(), iommu_aperture,
iommu_aperture_allowed, iommu_aperture_disabled. All these symbols are only
used for the GART implementation of IOMMUs.
It adds and additional gart_ prefix to them.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch renames the IOMMU config option to GART_IOMMU because in fact it
means the GART and not general support for an IOMMU on x86.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch renames the include file asm-x86/iommu.h to asm-x86/gart.h to make
clear to which IOMMU implementation it belongs. The patch also adds "GART" to
the Kconfig line.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Muli Ben-Yehuda <muli@il.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
fix this warning:
arch/x86/kernel/early-quirks.c:40: warning: nvidia_hpet_check defined but not used
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
They were already very similar; just use the same file now.
[ tglx: arch/x86 adaptation ]
Cc: lenb@kernel.org
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>