Gavin Shan [Mon, 5 May 2014 02:09:05 +0000 (12:09 +1000)]
powerpc/eeh: Fix build error for celleb
Commit 7f52a526f ("powerpc/eeh: Allow to disable EEH") caused
following build error with "celleb_defconfig" as being catched
by Mikey on linux-next.
arch/powerpc/kernel/eeh.c: In function 'eeh_init_proc':
arch/powerpc/kernel/eeh.c:1173:37: error: 'powerpc_debugfs_root' \
undeclared (first use in this function)
arch/powerpc/kernel/eeh.c:1173:37: note: each undeclared identifier \
is reported only once for each function it appears in
Reported-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This code was way too board specific, there are quirks as to how
the PERST line is wired on different boards, we'll have to revisit
this using/creating appropriate firmware interfaces.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Fri, 9 May 2014 07:47:12 +0000 (17:47 +1000)]
powerpc: irq work racing with timer interrupt can result in timer interrupt hang
I am seeing an issue where a CPU running perf eventually hangs.
Traces show timer interrupts happening every 4 seconds even
when a userspace task is running on the CPU. /proc/timer_list
also shows pending hrtimers have not run in over an hour,
including the scheduler.
Looking closer, decrementers_next_tb is getting set to
0xffffffffffffffff, and at that point we will never take
a timer interrupt again.
In __timer_interrupt() we set decrementers_next_tb to
0xffffffffffffffff and rely on ->event_handler to update it:
*next_tb = ~(u64)0;
if (evt->event_handler)
evt->event_handler(evt);
In this case ->event_handler is hrtimer_interrupt. This will eventually
call back through the clockevents code with the next event to be
programmed:
static int decrementer_set_next_event(unsigned long evt,
struct clock_event_device *dev)
{
/* Don't adjust the decrementer if some irq work is pending */
if (test_irq_work_pending())
return 0;
__get_cpu_var(decrementers_next_tb) = get_tb_or_rtc() + evt;
If irq work came in between these two points, we will return
before updating decrementers_next_tb and we never process a timer
interrupt again.
This looks to have been introduced by 0215f7d8c53f (powerpc: Fix races
with irq_work). Fix it by removing the early exit and relying on
code later on in the function to force an early decrementer:
/* We may have raced with new irq work */
if (test_irq_work_pending())
set_dec(1);
Signed-off-by: Anton Blanchard <anton@samba.org> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Resetting root port has more stuff to do than that for PCIe switch
ports and we should have resetting root port done in firmware instead
of the kernel itself. The problem was introduced by commit 5b2e198e
("powerpc/powernv: Rework EEH reset").
Merge remote-tracking branch 'anton/abiv2' into next
This series adds support for building the powerpc 64-bit
LE kernel using the new ABI v2. We already supported
running ABI v2 userspace programs but this adds support
for building the kernel itself using the new ABI.
Alistair Popple [Mon, 24 Feb 2014 07:00:56 +0000 (18:00 +1100)]
ppc476: Enable a linker work around for IBM errata #46
This patch adds an option to enable a work around for an icache bug on
476 that can cause execution of stale instructions when falling
through pages (IBM errata #46). It requires a recent version of
binutils which supports the --ppc476-workaround option.
The work around enables the appropriate linker options and ensures
that all module output sections are aligned to 4K page boundaries. The
work around is only required when building modules.
Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Alistair Popple [Thu, 6 Mar 2014 03:52:28 +0000 (14:52 +1100)]
powerpc: Added PCI MSI support using the HSTA module
The PPC476GTR SoC supports message signalled interrupts (MSI) by writing
to special addresses within the High Speed Transfer Assist (HSTA) module.
This patch adds support for PCI MSI with a new system device. The DMA
window is also updated to allow access to the entire 42-bit address range
to allow PCI devices write access to the HSTA module.
Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Alistair Popple [Thu, 6 Mar 2014 03:52:26 +0000 (14:52 +1100)]
IBM Currituck: Clean up board specific code before adding Akebono code
The IBM Akebono code uses the same initialisation functions as the
earlier Currituck board. Rather than create a copy of this code for
Akebono we will instead integrate support for it into the same file as
the Currituck code.
This patch just renames the board support file and updates the Makefile.
Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Unaligned stores take alignment exceptions on POWER7 running in little-endian.
This is a dumb little-endian base memcpy that prevents unaligned stores.
Once booted the feature fixup code switches over to the VMX copy loops
(which are already endian safe).
The question is what we do before that switch over. The base 64bit
memcpy takes alignment exceptions on POWER7 so we can't use it as is.
Fixing the causes of alignment exception would slow it down, because
we'd need to ensure all loads and stores are aligned either through
rotate tricks or bytewise loads and stores. Either would be bad for
all other 64bit platforms.
[ I simplified the loop a bit - Anton ]
Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Michael Neuling [Fri, 28 Mar 2014 05:40:34 +0000 (16:40 +1100)]
powerpc/tm: Add checking to treclaim/trechkpt
If we do a treclaim and we are not in TM suspend mode, it results in a TM bad
thing (ie. a 0x700 program check). Similarly if we do a trechkpt and we have
an active transaction or TEXASR Failure Summary (FS) is not set, we also take a
TM bad thing.
This should never happen, but if it does (ie. a kernel bug), the cause is
almost impossible to debug as the GPR state is mostly userspace and hence we
don't get a call chain.
This adds some checks in these cases case a BUG_ON() (in asm) in case we ever
hit these cases. It moves the register saving around to preserve r1 till later
also.
Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Implement a method named pnv_get_proc_freq(unsigned int cpu) which
returns the current clock rate on the 'cpu' in Hz to be reported in
/proc/cpuinfo. This method uses the value reported by cpufreq when
such a value is sane. Otherwise it falls back to old way of reporting
the clockrate, i.e. ppc_proc_freq.
Set the ppc_md.get_proc_freq() hook to pnv_get_proc_freq() on the
PowerNV platform.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc: powernv: Framework to show the correct clock in /proc/cpuinfo
Currently, the code in setup-common.c for powerpc assumes that all
clock rates are same in a smp system. This value is cached in the
variable named ppc_proc_freq and is the value that is reported in
/proc/cpuinfo.
However on the PowerNV platform, the clock rate is same only across
the threads of the same core. Hence the value that is reported in
/proc/cpuinfo is incorrect on PowerNV platforms. We need a better way
to query and report the correct value of the processor clock in
/proc/cpuinfo.
The patch achieves this by creating a machdep_call named
get_proc_freq() which is expected to returns the frequency in Hz. The
code in show_cpuinfo() can invoke this method to display the correct
clock rate on platforms that have implemented this method. On the
other powerpc platforms it can use the value cached in ppc_proc_freq.
Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Stephen Chivers [Sat, 19 Apr 2014 23:43:10 +0000 (09:43 +1000)]
powerpc/legacy_serial: Support MVME5100 UARTS with shifted registers
This patch adds support to legacy serial for
UARTS with shifted registers.
The MVME5100 Single Board Computer is a PowerPC platform
that has 16550 style UARTS with register addresses that are
16 bytes apart (shifted by 4).
Commit 309257484cc1a592e8ac5fbdd8cd661be2b80bf8
"powerpc: Cleanup udbg_16550 and add support for LPC PIO-only UARTs"
added support to udbg_16550 for shifted registers by adding a "stride"
parameter to the initialisation operations for Programmed IO and
Memory Mapped IO.
As a consequence it is now possible to use the services of legacy serial
to provide early serial console messages for the MVME5100.
An added benefit of this is that the serial console will always be
"ttyS0" irrespective of whether the computer is fitted with extra
PCI 8250 interface boards or not.
I have tested this patch using the four PowerPC platforms available to me:
powerpc/boot: Add support for 64bit little endian wrapper
The code is only slightly modified : entry points now use the
FIXUP_ENDIAN trampoline to switch endian order. The 32bit wrapper
is kept for big endian kernels and 64bit is enforced for little
endian kernels with a PPC64_BOOT_WRAPPER config option.
The linker script is generated using the kernel preprocessor flags
to make use of the CONFIG_* definitions and the wrapper script is
modified to take into account the new elf64ppc format.
Finally, the zImage file is compiled as a position independent
executable (-pie) which makes it loadable at any address by the
firmware.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/boot: Add a global entry point for pseries
When entering the boot wrapper in little endian, we will need to fix
the endian order using a fixup trampoline like in the kernel. This
patch overrides the _zimage_start entry point for this purpose.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds support a 64bit wrapper entry point. As in 32bit, the
entry point does its own relocation and can be loaded at any address
by the firmware.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch defines a 'prom' routine similar to 'enter_prom' in the
kernel.
The difference is in the MSR which is built before entering prom. Big
endian order is enforced as in the kernel but 32bit mode is not. It
prepares ground for the next patches which will introduce Little endian
order.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/boot: Add 64bit and little endian support to addnote
It could certainly be improved using Elf macros and byteswapping
routines, but the initial version of the code is organised to be a
single file program with limited dependencies. yaboot is the same.
Please scream if you want a total rewrite.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/boot/oflib.c:211:9: warning: cast to pointer from integer of \
different size [-Wint-to-pointer-cast]
return (phandle) of_call_prom("finddevice", 1, 1, name);
This is a work around. The definite solution would be to define the
phandle typedef as a u32, as in the kernel, but this would break the
device tree ops API.
Let it be for the moment.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/boot: Use a common prom_args struct in oflib
This patch fixes warnings when the wrapper is compiled in 64bit and
updates the boot wrapper code related to prom to converge with the
kernel code in prom_init. This should make the review of changes easier.
The kernel has a different number of possible arguments (10) when
entering prom. There does not seem to be any good reason to have
12 in the wrapper, so the patch changes this value to args[10] in
the prom_args struct.
Signed-off-by: Cédric Le Goater <clg@fr.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/prom: Stop scanning dev-tree for fdump early
Function early_init_dt_scan_fw_dump() is called to scan the device
tree for fdump properties under node "rtas". Any one of them is
invalid, we can stop scanning the device tree early by returning
"1". It would save a bit time during boot.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/powernv: Don't use pe->pbus to get the domain number
If the PE contains single PCI function, "pe->pbus" would be NULL.
It's not reliable to be used by pci_domain_nr(). We just grab the
PCI domain number from the PCI host controller (struct pci_controller)
instance.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In function pnv_pci_ioda2_setup_dma_pe(), the IOMMU table type is
set to (TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE) unconditionally.
It was just set to TCE_PCI by pnv_pci_setup_iommu_table(). So the
primary IOMMU table type (TCE_PCI) is lost. The patch fixes it.
Also, pnv_pci_setup_iommu_table() already set "tbl->it_busno" to
zero and we needn't do it again. The patch removes the redundant
assignment.
The patch also fixes similar issues in pnv_pci_ioda_setup_dma_pe().
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The patch intends to support fundamental reset on PLX downstream
ports. If the PCI device matches any one of the internal table,
which includes PLX vendor ID, bridge device ID, register offset
for fundamental reset and bit, fundamental reset will be done
accordingly. Otherwise, it will fail back to hot reset.
Additional flag (EEH_DEV_FRESET) is introduced to record the last
reset type on the PCI bridge.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When PCI_ERS_RESULT_CAN_RECOVER returned from device drivers, the
EEH core should enable I/O and DMA for the affected PE. However,
it was missed to have DMA enabled in eeh_handle_normal_event().
Besides, the frozen state of the affected PE should be cleared
after successful recovery, but we didn't.
The patch fixes both of the issues as above.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In the kdump scenario, the first kerenl doesn't shutdown PCI devices
and the kdump kerenl clean PHB IODA table at the early probe time.
That means the kdump kerenl can't support PCI transactions piled
by the first kerenl. Otherwise, lots of EEH errors and frozen PEs
will be detected.
In order to avoid the EEH errors, the PHB is resetted to drop all
PCI transaction from the first kerenl.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The problem was initially reported by Wendy who tried pass through
IPR adapter, which was connected to PHB root port directly, to KVM
based guest. When doing that, pci_reset_bridge_secondary_bus() was
called by VFIO driver and linkDown was detected by the root port.
That caused all PEs to be frozen.
The patch fixes the issue by routing the reset for the secondary bus
of root port to underly firmware. For that, one more weak function
pci_reset_secondary_bus() is introduced so that the individual platforms
can override that and do specific reset for bridge's secondary bus.
Basically, we have 3 types of resets to fulfil PE reset: fundamental,
hot and PHB reset. For the later 2 cases, we need PCI bus reset hold
and settlement delay as specified by PCI spec. PowerNV and pSeries
platforms are running on top of different firmware and some of the
delays have been covered by underly firmware (PowerNV).
The patch makes the delays unified to be done in backend, instead of
EEH core.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Resetting root port has more stuff to do than that for PCIe switch
ports and we should have resetting root port done in firmware instead
of the kernel itself. The problem was introduced by commit 5b2e198e
("powerpc/powernv: Rework EEH reset").
In pseries_eeh_get_state(), EEH_STATE_UNAVAILABLE is always
overwritten by EEH_STATE_NOT_SUPPORT because of the missed
"break" there. The patch fixes the issue.
Reported-by: Joe Perches <joe@perches.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Once one specific PE has been marked as EEH_PE_ISOLATED, it's in
the middile of recovery or removed permenently. We needn't report
the frozen PE again. Otherwise, we will have endless reporting
same frozen PE.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
PE#4 (have 2 PCI devices) is the child of PE#3, which has 2 p2p
bridges. We accidentally had less-known scenario: PE#4 was removed
permanently from the system because of permanent failure (e.g.
exceeding the max allowd failure times in last hour), then we detects
EEH errors on PE#3 and tried to recover it. However, eeh_dev instances
for pdev#0/1 were not detached from PE#4, which was still connected to
PE#3. All of that was because of the fact that we rely on count-based
pcibios_release_device(), which isn't reliable enough. When doing
recovery for PE#3, we still apply hotplug on PE#4 and pdev#0/1, which
are not valid any more. Eventually, we run into kernel crash.
The patch fixes above issue from two aspects. For unplug, we simply
skip those permanently removed PE, whose state is (EEH_PE_STATE_ISOLATED
&& !EEH_PE_STATE_RECOVERING) and its frozen count should be greater
than EEH_MAX_ALLOWED_FREEZES. For plug, we marked all permanently
removed EEH devices with EEH_DEV_REMOVED and return 0xFF's on read
its PCI config so that PCI core will omit them.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The patch introduces bootarg "eeh=off" to disable EEH functinality.
Also, it creates /sys/kerenl/debug/powerpc/eeh_enable to disable
or enable EEH functionality. By default, we have the functionality
enabled.
For PowerNV platform, we will restore to have the conventional
mechanism of clearing frozen PE during PCI config access if we're
going to disable EEH functionality. Conversely, we will rely on
EEH for error recovery.
The patch also fixes the issue that we missed to cover the case
of disabled EEH functionality in function ioda_eeh_event(). Those
events driven by interrupt should be cleared to avoid endless
reporting.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There're 2 EEH subsystem variables: eeh_subsystem_enabled and
eeh_probe_mode. We needn't maintain 2 variables and we can just
have one variable and introduce different flags. The patch also
introduces additional flag EEH_FORCE_DISABLE, which will be used
to disable EEH subsystem via boot parameter ("eeh=off") in future.
Besides, the patch also introduces flag EEH_ENABLED, which is
changed to disable or enable EEH functionality on the fly through
debugfs entry in future.
With the patch applied, the creteria to check the enabled EEH
functionality is changed to:
!EEH_FORCE_DISABLED && EEH_ENABLED : Enabled
Other cases : Disabled
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When calling into eeh_gather_pci_data() on pSeries platform, we
possiblly don't have pci_dev instance yet, but eeh_dev is always
ready. So we use cached capability from eeh_dev instead of pci_dev
for log dump there. In order to keep things unified, we also cache
PCI capability positions to eeh_dev for PowerNV as well.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have suffered recrusive frozen PE a lot, which was caused
by IO accesses during the PE reset. Ben came up with the good
idea to keep frozen PE until recovery (BAR restore) gets done.
With that, IO accesses during PE reset are dropped by hardware
and wouldn't incur the recrusive frozen PE any more.
The patch implements the idea. We don't clear the frozen state
until PE reset is done completely. During the period, the EEH
core expects unfrozen state from backend to keep going. So we
have to reuse EEH_PE_RESET flag, which has been set during PE
reset, to return normal state from backend. The side effect is
we have to clear frozen state for towice (PE reset and clear it
explicitly), but that's harmless.
We have some limitations on pHyp. pHyp doesn't allow to enable
IO or DMA for unfrozen PE. So we don't enable them on unfrozen PE
in eeh_pci_enable(). We have to enable IO before grabbing logs on
pHyp. Otherwise, 0xFF's is always returned from PCI config space.
Also, we had wrong return value from eeh_pci_enable() for
EEH_OPT_THAW_DMA case. The patch fixes it too.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
For EEH PowerNV backends, they need use their own PCI config
accesors as the normal one could be blocked during PE reset.
The patch also removes necessary parameter "hose" for the
function ioda_eeh_bridge_reset().
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We've observed multiple PE reset failures because of PCI-CFG
access during that period. Potentially, some device drivers
can't support EEH very well and they can't put the device to
motionless state before PE reset. So those device drivers might
produce PCI-CFG accesses during PE reset. Also, we could have
PCI-CFG access from user space (e.g. "lspci"). Since access to
frozen PE should return 0xFF's, we can block PCI-CFG access
during the period of PE reset so that we won't get recrusive EEH
errors.
The patch adds flag EEH_PE_RESET, which is kept during PE reset.
The PowerNV/pSeries PCI-CFG accessors reuse the flag to block
PCI-CFG accordingly.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When doing PE reset, EEH_PE_ISOLATED is cleared unconditionally.
However, We should remove that if the PE reset has cleared the
frozen state successfully. Otherwise, the flag should be kept.
The patch fixes the issue.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/powernv: Remove fields in PHB diag-data dump
For some fields (e.g. LEM, MMIO, DMA) in PHB diag-data dump, it's
meaningless to print them if they have non-zero value in the
corresponding mask registers because we always have non-zero values
in the mask registers. The patch only prints those fieds if we
have non-zero values in the primary registers (e.g. LEM, MMIO, DMA
status) so that we can save couple of lines. The patch also removes
unnecessary spare line before "brdgCtl:" and two leading spaces as
prefix in each line as Ben suggested.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/powernv: Move PNV_EEH_STATE_ENABLED around
The flag PNV_EEH_STATE_ENABLED is put into pnv_phb::eeh_state,
which is protected by CONFIG_EEH. We needn't that. Instead, we
can have pnv_phb::flags and maintain all flags there, which is
the purpose of the patch. The patch also renames PNV_EEH_STATE_ENABLED
to PNV_PHB_FLAG_EEH.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The PHB state PNV_EEH_STATE_REMOVED maintained in pnv_phb isn't
so useful any more and it's duplicated to EEH_PE_ISOLATED. The
patch replaces PNV_EEH_STATE_REMOVED with EEH_PE_ISOLATED.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The PE state (for eeh_pe instance) EEH_PE_PHB_DEAD is duplicate to
EEH_PE_ISOLATED. Originally, those PHBs (PHB PE) with EEH_PE_PHB_DEAD
would be removed from the system. However, it's safe to replace
that with EEH_PE_ISOLATED.
The patch also clear EEH_PE_RECOVERING after fenced PHB has been handled,
either failure or success. It makes the PHB PE state consistent with:
PHB functions normally NONE
PHB has been removed EEH_PE_ISOLATED
PHB fenced, recovery in progress EEH_PE_ISOLATED | RECOVERING
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
WARNING: vmlinux.o(.text+0x1efc4): Section mismatch in reference from
the function apm821xx_pciex_init_port_hw() to the function
.init.text:ppc4xx_pciex_wait_on_sdr.isra.9()
The function apm821xx_pciex_init_port_hw() references the function
__init ppc4xx_pciex_wait_on_sdr.isra.9(). This is often because
apm821xx_pciex_init_port_hw lacks a __init annotation or the
annotation of ppc4xx_pciex_wait_on_sdr.isra.9 is wrong.
apm821xx_pciex_init_port_hw is only referenced by a struct in
__initdata, so it should be safe to add __init to
apm821xx_pciex_init_port_hw.
Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
ppc/kvm: Clear the runlatch bit of a vcpu before napping
When the guest cedes the vcpu or the vcpu has no guest to
run it naps. Clear the runlatch bit of the vcpu before
napping to indicate an idle cpu.
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
ppc/kvm: Set the runlatch bit of a CPU just before starting guest
The secondary threads in the core are kept offline before launching guests
in kvm on powerpc: "371fefd6f2dc4666:KVM: PPC: Allow book3s_hv guests to use
SMT processor modes."
Hence their runlatch bits are cleared. When the secondary threads are called
in to start a guest, their runlatch bits need to be set to indicate that they
are busy. The primary thread has its runlatch bit set though, but there is no
harm in setting this bit once again. Hence set the runlatch bit for all
threads before they start guest.
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
ppc/powernv: Set the runlatch bits correctly for offline cpus
Up until now we have been setting the runlatch bits for a busy CPU and
clearing it when a CPU enters idle state. The runlatch bit has thus
been consistent with the utilization of a CPU as long as the CPU is online.
However when a CPU is hotplugged out the runlatch bit is not cleared. It
needs to be cleared to indicate an unused CPU. Hence this patch has the
runlatch bit cleared for an offline CPU just before entering an idle state
and sets it immediately after it exits the idle state.
Signed-off-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Li Zhong [Thu, 10 Apr 2014 08:25:31 +0000 (16:25 +0800)]
powerpc/pseries: Protect remove_memory() with device hotplug lock
While testing memory hot-remove, I found following dead lock:
Process #1141 is drmgr, trying to remove some memory, i.e. memory499.
It holds the memory_hotplug_mutex, and blocks when trying to remove file
"online" under dir memory499, in kernfs_drain(), at
wait_event(root->deactivate_waitq,
atomic_read(&kn->active) == KN_DEACTIVATED_BIAS);
Process #1120 is trying to online memory499 by
echo 1 > memory499/online
In .kernfs_fop_write, it uses kernfs_get_active() to increase
&kn->active, thus blocking process #1141. While itself is blocked later
when trying to acquire memory_hotplug_mutex, which is held by process
This patch uses lock_device_hotplug() to protect remove_memory() called
in pseries_remove_memblock(), which is also stated before function
remove_memory():
* NOTE: The caller must call lock_device_hotplug() to serialize hotplug
* and online/offline operations before this call, as required by
* try_offline_node().
*/
void __ref remove_memory(int nid, u64 start, u64 size)
With this lock held, the other process(#1120 above) trying to online the
memory block will retry the system call when calling
lock_device_hotplug_sysfs(), and finally find No such device error.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have two definitions of COMMAND_LINE_SIZE, one for the kernel
and one for the boot wrapper. I assume this is so the boot
wrapper can be self sufficient and not rely on kernel headers.
Having two defines with the same name is confusing, I just
updated the wrong one when trying to bump it.
Make the boot wrapper define unique by calling it
BOOT_COMMAND_LINE_SIZE.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Tue, 22 Apr 2014 05:01:26 +0000 (15:01 +1000)]
powerpc/powernv: Create OPAL sglist helper functions and fix endian issues
We have two copies of code that creates an OPAL sg list. Consolidate
these into a common set of helpers and fix the endian issues.
The flash interface embedded a version number in the num_entries
field, whereas the dump interface did did not. Since versioning
wasn't added to the flash interface and it is impossible to add
this in a backwards compatible way, just remove it.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Tue, 22 Apr 2014 05:01:25 +0000 (15:01 +1000)]
powerpc/powernv: Fix little endian issues in OPAL error log code
Fix little endian issues with the OPAL error log code.
Signed-off-by: Anton Blanchard <anton@samba.org> Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Tue, 22 Apr 2014 05:01:22 +0000 (15:01 +1000)]
powerpc/powernv: Use uint64_t instead of size_t in OPAL APIs
Using size_t in our APIs is asking for trouble, especially
when some OPAL calls use size_t pointers.
Signed-off-by: Anton Blanchard <anton@samba.org> Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Wei Yang [Wed, 23 Apr 2014 02:26:32 +0000 (10:26 +0800)]
powerpc/powernv: Reduce multi-hit of iommu_add_device()
During the EEH hotplug event, iommu_add_device() will be invoked three times
and two of them will trigger warning or error.
The three times to invoke the iommu_add_device() are:
pci_device_add
...
set_iommu_table_base_and_group <- 1st time, fail
device_add
...
tce_iommu_bus_notifier <- 2nd time, succees
pcibios_add_pci_devices
...
pcibios_setup_bus_devices <- 3rd time, re-attach
The first time fails, since the dev->kobj->sd is not initialized. The
dev->kobj->sd is initialized in device_add().
The third time's warning is triggered by the re-attach of the iommu_group.
After applying this patch, the error
iommu_tce: 0003:05:00.0 has not been added, ret=-14
This patch removes iommu_add_device() in pnv_pci_ioda_dma_dev_setup(), which
revert part of the change in commit d905c5df(PPC: POWERNV: move
iommu_add_device earlier).
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc/powernv: Fix kexec races going back to OPAL
We have a subtle race when sending CPUs back to OPAL on kexec.
We mark them as "in real mode" right before we send them down. Once
we've booted the new kernel, it might try to call opal_reinit_cpus()
to change endianness, and that requires all CPUs to be spinning inside
OPAL.
However there is no synchronization here and we've observed cases
where the returning CPUs hadn't established their new state inside
OPAL before opal_reinit_cpus() is called, causing it to fail.
The proper fix is to actually wait for them to go down all the way
from the kexec'ing kernel.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Joel Stanley [Thu, 24 Apr 2014 07:25:37 +0000 (16:55 +0930)]
powerpc/powernv: Check sysparam size before creation
The size of the sysparam sysfs files is determined from the device tree
at boot. However the buffer is hard coded to 64 bytes. If we encounter a
parameter that is larger than 64, or miss-parse the device tree, the
buffer will overflow when reading or writing to the parameter.
Check it at discovery time, and if the parameter is too large, do not
create a sysfs entry for it.
Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Joel Stanley [Thu, 24 Apr 2014 07:25:34 +0000 (16:55 +0930)]
powerpc/powernv: Use ssize_t for sysparam return values
The OPAL calls are returning int64_t values, which the sysparam code
stores in an int, and the sysfs callback returns ssize_t. Make code a
easier to read by consistently using ssize_t.
Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When a sysparam query in OPAL returned a negative value (error code),
sysfs would spew out a decent chunk of memory; almost 64K more than
expected. This was traced to a sign/unsigned mix up in the OPAL sysparam
sysfs code at sys_param_show.
The return value of sys_param_show is a ssize_t, calculated using
return ret ? ret : attr->param_size;
Alan Modra explains:
"attr->param_size" is an unsigned int, "ret" an int, so the overall
expression has type unsigned int. Result is that ret is cast to
unsigned int before being cast to ssize_t.
Instead of using the ternary operator, set ret to the param_size if an
error is not detected. The same bug exists in the sysfs write callback;
this patch fixes it in the same way.
A note on debugging this next time: on my system gcc will warn about
this if compiled with -Wsign-compare, which is not enabled by -Wall,
only -Wextra.
Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Li Zhong [Mon, 28 Apr 2014 00:29:51 +0000 (08:29 +0800)]
powerpc: Fix Oops in rtas_stop_self()
commit 41dd03a9 may cause Oops in rtas_stop_self().
The reason is that the rtas_args was moved into stack space. For a box
with more that 4GB RAM, the stack could easily be outside 32bit range,
but RTAS is 32bit.
So the patch moves rtas_args away from stack by adding static before
it.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Jeff Mahoney [Sun, 27 Apr 2014 22:10:43 +0000 (18:10 -0400)]
powerpc: Export flush_icache_range
Commit aac416fc38c (lkdtm: flush icache and report actions) calls
flush_icache_range from a module. It's exported on most architectures
that implement it, but not on powerpc. This patch exports it to fix
the module link failure.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Mon, 10 Mar 2014 10:06:12 +0000 (21:06 +1100)]
powerpc: Build little endian ppc64 kernel with ABIv2
Build the little endian ppc64 kernel with ABIv2 if the toolchain
supports it. We can identify an ABIv2 capable toolchain by the
-mabi=elfv2 compiler flag.
Anton Blanchard [Fri, 4 Apr 2014 05:54:04 +0000 (16:54 +1100)]
powerpc/ftrace: Fix ABIv2 issues with __ftrace_make_call
__ftrace_make_call assumed ABIv1 TOC stack offsets, so it
broke on ABIv2.
While we are here, we can simplify the instruction modification
code. Since we always update one instruction there is no need to
probe_kernel_write and flush_icache_range, just use patch_branch.
ftrace has way too much knowledge of our kernel module trampoline
layout hidden inside it. Create module_trampoline_target() that gives
the target address of a kernel module trampoline.
Anton Blanchard [Thu, 3 Apr 2014 09:00:43 +0000 (20:00 +1100)]
powerpc/modules: Create is_module_trampoline()
ftrace has way too much knowledge of our kernel module trampoline
layout hidden inside it. Create is_module_trampoline() that can
abstract this away inside the module loader code.