Anton Blanchard [Mon, 13 Oct 2014 08:41:38 +0000 (19:41 +1100)]
powerpc: Reimplement __get_SP() as a function not a define
Li Zhong points out an issue with our current __get_SP()
implementation. If ftrace function tracing is enabled (ie -pg
profiling using _mcount) we spill a stack frame on 64bit all the
time.
If a function calls __get_SP() and later calls a function that is
tail call optimised, we will pop the stack frame and the value
returned by __get_SP() is no longer valid. An example from Li can
be found in save_stack_trace -> save_context_stack:
save_context_stack ends up with a stack pointer below the current
one, and it is likely to be scribbled over.
Fix this by making __get_SP() a function which returns the
callers stack frame. Also replace inline assembly which grabs
the stack pointer in save_stack_trace and show_stack with
__get_SP().
This also fixes an issue with perf_arch_fetch_caller_regs().
It currently unwinds the stack once, which will skip a
valid stack frame on a leaf function. With the __get_SP() fixes
in this patch, we never need to unwind the stack frame to get
to the first interesting frame.
We have to export __get_SP() because perf_arch_fetch_caller_regs()
(which is used in modules) calls it from a header file.
Reported-by: Li Zhong <zhong@linux.vnet.ibm.com> Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/numa: Add ability to disable and debug topology updates
We have hit a few customer issues with the topology update code (VPHN
and PRRN). It would be nice to be able to debug the notifications coming
from the hypervisor in both cases to the LPAR, as well as to disable
responding to the notifications at boot-time, to narrow down the source
of the problems. Add a basic level of such functionality, similar to the
numa= command-line parameter. We already have a toggle in
/proc/powerpc/topology_updates that allows run-time enabling/disabling,
so the updates can be started at run-time if desired. But the bugs we've
run into have occured during boot or very shortly after coming to login,
and have resulted in a broken NUMA topology.
Signed-off-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv: Fallback to old HMI handling behavior for old firmware
Recently we moved HMI handling into Linux kernel instead of taking
HMI directly in OPAL. This new change is dependent on new OPAL call
for HMI recovery which was introduced in newer firmware. While this new
change works fine with latest OPAL firmware, we broke the HMI handling
if we run newer kernel on old OPAL firmware that results in system hang.
This patch fixes this issue by falling back to old HMI behavior on older
OPAL firmware.
This patch introduces a check for opal token OPAL_HANDLE_HMI to see
if we are running on newer firmware or old firmware. On newer firmware
this check would return OPAL_TOKEN_PRESENT, otherwise we are running on
old firmware and fallback to old HMI behavior.
Old firmware: POWER8 System Firmware Release as of today <= SV810_087
Action: Let OPAL handle HMIs
Newer firmware: in development/yet to be released.
Action: Let Linux host handle HMIs.
This patch depends on opal check token patch posted at ppc-devel
https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-August/120224.html
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
[mpe: Minor comment and printk rewording] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The actual sys_call_table symbol, declared in assembler, is an
array. If we lie about that to the compiler we get the wrong code
generated, as above.
This definition seems only to be used by the syscall tracing code in
kernel/trace/trace_syscalls.c. With this patch I can successfully use
the syscall tracepoints:
Ian Munsie [Thu, 9 Oct 2014 00:17:46 +0000 (11:17 +1100)]
cxl: Fix afu_read() not doing finish_wait() on signal or non-blocking
If afu_read() returned due to a signal or the AFU file descriptor being
opened non-blocking it would not call finish_wait() before returning,
which could lead to a crash later when something else wakes up the wait
queue.
This patch restructures the wait logic to ensure that the cleanup is
done correctly.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:05 +0000 (19:55 +1100)]
cxl: Add documentation for userspace APIs
This documentation gives an overview of the hardware architecture, userspace
APIs via /dev/cxl/afuM.N and the syfs files. It also adds a MAINTAINERS file
entry for cxl.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:04 +0000 (19:55 +1100)]
cxl: Add driver to Kbuild and Makefiles
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:03 +0000 (19:55 +1100)]
cxl: Add userspace header file
This adds a header file for use by userspace programs wanting to interact with
the kernel cxl driver. It defines structs and magic numbers required for
userspace to interact with devices in /dev/cxl/afuM.N.
Further documentation on this interface is added in a subsequent patch in
Documentation/powerpc/cxl.txt.
It also adds this new userspace header file to Kbuild so it's exported when
doing "make headers_installs".
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:02 +0000 (19:55 +1100)]
cxl: Driver code for powernv PCIe based cards for userspace access
This is the core of the cxl driver.
It adds support for using cxl cards in the powernv environment only (ie POWER8
bare metal). It allows access to cxl accelerators by userspace using the
/dev/cxl/afuM.N char devices.
The kernel driver has no knowledge of the function implemented by the
accelerator. It provides services to userspace via the /dev/cxl/afuM.N
devices. When a program opens this device and runs the start work IOCTL, the
accelerator will have coherent access to that processes memory using the same
virtual addresses. That process may mmap the device to access any MMIO space
the accelerator provides. Also, reads on the device will allow interrupts to
be received. These services are further documented in a later patch in
Documentation/powerpc/cxl.txt.
Documentation of the cxl hardware architecture and userspace API is provided in
subsequent patches.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:01 +0000 (19:55 +1100)]
cxl: Add base builtin support
This adds the base cxl support that cannot be built as a module. Specifically
it adds the cxl callbacks that are called from the core powerpc mm code which
must always exist irrespective of if the cxl module is loaded or not. This is
similar to how cell works with CONFIG_SPU_BASE.
This adds a cxl_slbia() call (similar to spu_flush_all_slbs()) which checks if
the cxl module is loaded and in use, returning immediately if it is not. If it
is in use it calls into the cxl SLB invalidation code.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:55:00 +0000 (19:55 +1100)]
powerpc/mm: Add hooks for cxl
This adds hooks into the core powerpc mm code for cxl.
The core powerpc code sometimes uses local tlbie. Unfortunately this won't
work with the current cxl driver as it relies on snooping tlbie broadcasts.
The cxl hardware can have TLB entries invalidated via MMIO but this is not
currently supported by the driver. In future we can make local tlbie smarter so
that it invalidates cxl contexts via MMIO when it needs to but for now we have
this workaround.
This workaround checks for any active cxl contexts and if so, disables local
tlbie.
This also adds a hook for when SLBs are invalidated. This ensures any
corresponding SLBs in cxl are also invalidated at the same time. This is
required for segment demotion.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:59 +0000 (19:54 +1100)]
powerpc/opal: Add PHB to cxl mode call
This adds the OPAL call to change a PHB into cxl mode.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:58 +0000 (19:54 +1100)]
powerpc/mm: Add new hash_page_mm()
This adds a new function hash_page_mm() based on the existing hash_page().
This version allows any struct mm to be passed in, rather than assuming
current. This is useful for servicing co-processor faults which are not in the
context of the current running process.
We need to be careful here as the current hash_page() assumes current in a few
places.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:57 +0000 (19:54 +1100)]
powerpc/powerpc: Add new PCIe functions for allocating cxl interrupts
This adds a number of functions for allocating IRQs under powernv PCIe for cxl.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:56 +0000 (19:54 +1100)]
cxl: Add new header for call backs and structs
This new header adds callbacks and structs needed by the rest of the kernel to
hook into the cxl infrastructure.
This adds the cxl_ctx_in_use() function for use in the mm code to see if any
cxl contexts are currently in use. This is used by the tlbie() to determine if
it can do local TLB invalidations or not. This also adds get/put calls for the
cxl driver module to refcount the active cxl contexts.
cxl_ctx_get/put/in_use are static inlined here as they are called in tlbie
which we want to be fast (mpe's suggestion).
Empty functions are provided when CONFIG_CXL_BASE is not enabled.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:55 +0000 (19:54 +1100)]
powerpc/powernv: Split out set MSI IRQ chip code
Some of the MSI IRQ code in pnv_pci_ioda_msi_setup() is generically useful so
split it out.
This will be used by some of the cxl PCIe code later.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:54 +0000 (19:54 +1100)]
powerpc/mm: Export mmu_kernel_ssize and mmu_linear_psize
Export mmu_kernel_ssize and mmu_linear_psize. These are needed by the cxl
driver which has it's own MMU. To setup the MMU cxl needs access to these.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:53 +0000 (19:54 +1100)]
powerpc/msi: Improve IRQ bitmap allocator
Currently msi_bitmap_alloc_hwirqs() will round up any IRQ allocation requests
to the nearest power of 2. eg. ask for 5 IRQs and you'll get 8. This wastes a
lot of IRQs which can be a scarce resource.
For cxl we may require multiple IRQs for every context that is attached to the
accelerator. There may be 1000s of contexts attached, hence we can easily run
out of IRQs, especially if we are needlessly wasting them.
This changes the msi_bitmap_alloc_hwirqs() to allocate only the required number
of IRQs, hence avoiding this wastage. It keeps the natural alignment
requirement though.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:52 +0000 (19:54 +1100)]
powerpc/cell: Make spu_flush_all_slbs() generic
This moves spu_flush_all_slbs() into a generic call copro_flush_all_slbs().
This will be useful when we add cxl which also needs a similar SLB flush call.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:51 +0000 (19:54 +1100)]
powerpc/cell: Move data segment faulting code out of cell platform
__spu_trap_data_seg() currently contains code to determine the VSID and ESID
required for a particular EA and mm struct.
This code is generically useful for other co-processors. This moves the code of
the cell platform so it can be used by other powerpc code. It also adds 1TB
segment handling which Cell didn't support. The new function is called
copro_calculate_slb().
This also moves the internal struct spu_slb to a generic struct copro_slb which
is now used in the Cell and copro code. We use this new struct instead of
passing around esid and vsid parameters.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ian Munsie [Wed, 8 Oct 2014 08:54:50 +0000 (19:54 +1100)]
powerpc/cell: Move spu_handle_mm_fault() out of cell platform
Currently spu_handle_mm_fault() is in the cell platform.
This code is generically useful for other non-cell co-processors on powerpc.
This patch moves this function out of the cell platform into arch/powerpc/mm so
that others may use it.
Signed-off-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It essentially takes a buffer, an offset and count as parameters
to the read() call. It makes a hypervisor call to read a specific
page from the catalog and copy the required bytes into the given
buffer. Each call to catalog_read() returns at most one 4K page.
Given these requirements, we should be able to simplify the
catalog_read().
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cody P Schafer [Wed, 1 Oct 2014 06:03:17 +0000 (23:03 -0700)]
powerpc/perf/hv-24x7: use kmem_cache instead of aligned stack allocations
Ian pointed out the use of __aligned(4096) caused rather large stack
consumption in single_24x7_request(), so use the kmem_cache
hv_page_cache (which we've already got set up for other allocations)
insead of allocating locally.
CC: Haren Myneni <hbabu@us.ibm.com> Reported-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Cody P Schafer <dev@codyps.com> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv: Fix endian bug in LPC bus debugfs accessors
When reading from the LPC, the OPAL FW calls return the value via pointer
to a uint32_t which is always returned big endian. Our internal inb/outb
implementation byteswaps that fine but our debugfs code is still broken.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: <stable@vger.kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux.git
Freescale updates from Scott (27 commits):
"Highlights include DMA32 zone support (SATA, USB, etc now works on 64-bit
FSL kernels), MSI changes, 8xx optimizations and cleanup, t104x board
support, and PrPMC PCI enumeration."
rtas_call() accepts and returns values in CPU endianness.
The ddw_query_response and ddw_create_response structs members are
defined and treated as BE but as they are passed to rtas_call() as
(u32 *) and they get byteswapped automatically, the data is CPU-endian.
This fixes ddw_query_response and ddw_create_response definitions and use.
of_read_number() is designed to work with device tree cells - it assumes
the input is big-endian and returns data in CPU-endian. However due
to the ddw_create_response struct fix, create.addr_hi/lo are already
CPU-endian so do not byteswap them.
ddw_avail is a pointer to the "ibm,ddw-applicable" property which contains
3 cells which are big-endian as it is a device tree. rtas_call() accepts
a RTAS token in CPU-endian. This makes use of of_property_read_u32_array
to byte swap and avoid the need for a number of be32_to_cpu calls.
Cc: stable@vger.kernel.org # v3.13+ Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[aik: folded Anton's patch with of_property_read_u32_array] Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Anton Blanchard [Thu, 2 Oct 2014 05:44:21 +0000 (15:44 +1000)]
powerpc: Speed up clear_page by unrolling it
Unroll clear_page 8 times. A simple microbenchmark which
allocates and frees a zeroed page:
for (i = 0; i < iterations; i++) {
unsigned long p = __get_free_page(GFP_KERNEL | __GFP_ZERO);
free_page(p);
}
improves 20% on POWER8.
This assumes cacheline sizes won't grow beyond 512 bytes or
page sizes wont drop below 1kB, which is unlikely, but we could
add a runtime check during early init if it makes people nervous.
Michael found that some versions of gcc produce quite bad code
(all multiplies), so we give gcc a hand by using shifts and adds.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Gavin Shan [Wed, 1 Oct 2014 04:34:51 +0000 (14:34 +1000)]
powerpc/eeh: Show hex prefix for PE state sysfs
As Michael suggested, the hex prefix for the output of EEH PE
state sysfs entry (/sys/bus/pci/devices/xxx/eeh_pe_state) is
always informative to users.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The dma_get_required_mask() function is used by some drivers to
query the platform about what DMA mask is needed to cover all of
memory. This is a bit of a strange semantic when we have to choose
between IOMMU translation or bypass, but essentially what it means
is "what DMA mask will give best performances".
Currently, our IOMMU backend always returns a 32-bit mask here, we
don't do anything special to it when we have bypass available. This
causes some drivers to choose a 32-bit mask, thus losing the ability
to use the bypass window, thinking this is more efficient. The problem
was reported from the driver of following device:
This patch adds an override of that function in order to, instead,
return a 64-bit mask whenever a bypass window is available in order
for drivers to prefer this configuration.
Reported-by: Murali N. Iyer <mniyer@us.ibm.com> Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It should have been part of commit 1ad7a72c5 ("powerpc/eeh: Report
frozen parent PE prior to child PE"). There are 2 ways to report
EEH errors: proactively polling because of 0xFF's returned from
PCI config or IO read, or interrupt driven event. We missed to
report and handle parent frozen PE prior to child frozen PE for
the later case on PowerNV platform.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/eeh: Dump PCI config space for all child devices
The PEs can be organized as nested. Current implementation doesn't
dump PCI config space for subordinate devices of child PEs. However,
the frozen PE could be caused by those subordinate devices of its
child PEs.
The patch dumps PCI config space for all subordinate devices of the
problematic PE.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/eeh: Emulate EEH recovery for VFIO devices
When enabling EEH functionality on passed through devices (PE)
with VFIO, the devices in the PE would be removed permanently
from guest side. In that case, the PE remains frozen state.
When returning PE to host, or restarting the guest again, we
had mechanism unfreezing the PE by clearing PESTA/B frozen
bits. However, that's not enough for some adapters, which are
indicated as following "lspci" shows. Those adapters require
hot reset on the parent bus to bring their firmware back to
workable state. Otherwise, those adaptrs won't be operative
and the host (for returning case) or the guest will fail to
load the drivers for those adapters without exception.
The patch adds mechanism to emulate EEH recovery (for hot reset
on parent PCI bus) on 3 gates to fix the issue: open/release one
adapter of the PE, enable EEH functionality on one adapter of the
PE.
PE would be owned by userland, which probably request PE reset
done in host side. During the reset, we should drop the PCI
config accesses to the PE with help of flag EEH_PE_RESET.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/pseries: Decrease message level on EEH initialization
As Anton suggested, the patch decreases the message level on EEH
initialization to avoid unnecessary messages if required. Also,
we have unified hint if any of needful RTAS calls is missed, and
then we can check /proc/device-tree to figure out the missed RTAS
calls.
Suggested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Function pcibios_set_pcie_reset_state() can be used to do PCI
reset. PCI config access during the reset usually causes EEH
errors unexpectedly. In order to avoid the EEH error, the patch
blocks PCI config access during reset with the help of flag
EEH_PE_RESET, which is similar to what we did in EEH PE reset
path.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/eeh: Unfreeze PE on enabling EEH functionality
When passing through PE to guest, that's possibly in frozen
state. The driver for the pass-through devices on guest side
can't be loaded successfully as reported. We already had one
gate in eeh_dev_open() to clear PE frozen state accordingly,
but that's not enough because the function is only called at
QEMU startup for once.
The patch adds another gate in eeh_pe_set_option() so that the
PE frozen state can be cleared at QEMU restart time.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/eeh: Fix improper condition in eeh_pci_enable()
The function eeh_pci_enable() is called to apply various requests
to one particular PE: Enabling EEH, Disabling EEH, Enabling IO,
Enabling DMA, Freezing PE. When enabling IO or DMA on one specific
PE, we need check that IO or DMA isn't enabled previously. But
the condition used to do the check isn't completely correct because
one PE would be in DMA frozen state with workable IO path, or vice
versa.
The patch fixes the improper condition.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The problem was reported by Carol: In the scenario of passing mlx4
adapter to guest, EEH error could be recovered successfully. When
returning the device back to host, the driver (mlx4_core.ko)
couldn't be loaded successfully because of error number -5 (-EIO)
returned from mlx4_get_ownership(), which hits offlined PCI device.
The root cause is that we missed to put the affected devices into
normal state on clearing PE isolated state right after PE reset.
The patch fixes above issue by putting the affected devices to
normal state when clearing PE isolated state in eeh_pe_state_clear().
Cc: stable@vger.kernel.org Reported-by: Carol L. Soto <clsoto@us.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The frozen state on one specific PE is probably caused by error
injection, which is done with help of PAPR error injection registers.
According to the hardware spec, those registers should be cleared
automatically after one-shot frozen PE. However, that's not always
true, at least on P7IOC of Firebird-L. So we have to clear them
before doing PE reset to avoid recursive EEH errors at recovery
stage.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The patch adds debugfs file (/sys/kernel/debug/powerpc/PCIxxxx/
err_injct), which accepts following formated string, to support
error injection. It will be used to support userland utility
"errinjct" in future.
The patch introduces eeh_ops::err_inject(), which allows to inject
specified errors to indicated PE for testing purpose. The functionality
isn't support on pSeries platform. On PowerNV, the functionality
relies on OPAL API opal_pci_err_inject().
Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When passing through device, its PE might have been put into frozen
state. One obvious example would be: the passed PE is forced to be
offline because of hitting maximal allowed EEH errors in userland.
In that case, the frozen state won't be cleared and then the PE is
returned back to host, which might not have chance detecting and
recovering from it.
The patch adds more check when passing through device and clear the
PE frozen state if necessary.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The PCI devices that have been passed through are enabled before
reset, we need restore to the enabled state after reset. Otherwise,
MMIO access might be issued to disabled devices after reset and
causes exceptional recursive EEH error.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The patch adds one more option (EEH_OPT_FREEZE_PE) to set_option()
method to proactively freeze PE, which will be issued before resetting
pass-throughed PE to drop MMIO access during reset because it's
always contributing to recursive EEH error.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The patch adds sysfs entry "eeh_pe_state". Reading on it returns
the PE's state while writing to it clears the frozen state. It's
used to check or clear the PE frozen state from userland for
debugging purpose.
The patch also replaces printk(KERN_WARNING ...) with pr_warn() in
eeh_sysfs.c
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/eeh: Drop unused argument in eeh_check_failure()
eeh_check_failure() is used to check frozen state of the PE which
owns the indicated I/O address. The argument "val" of the function
isn't used. The patch drops it and return the frozen state of the
PE as expected.
Cc: Vishal Mansur <vmansur@linux.vnet.ibm.com> Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It uses mprotect to force a SEGV across a page boundary, and a SEGV
handler to lookup the exception tables and run the fixup routine.
It also compares the result against a normal load.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch introduces a macro to convert eeh_dev to eeh_pe. By doing so, it
will prevent converting with NULL pointer.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com> CC: Michael Ellerman <mpe@ellerman.id.au>
V3 -> V4:
1. move the macro definition from include/linux/pci.h to
arch/powerpc/include/asm/eeh.h
V2 -> V3:
1. rebased on 3.17-rc4
2. introduce a macro
3. use this macro in several other places
V1 -> V2:
1. code style and patch subject adjustment
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We can unindent the bulk of htab_dt_scan_page_sizes() by returning early
if the property is not found. That is nice in and of itself, but also
has the advantage of making it clear that we always return success once
we have found the ibm,segment-page-sizes property.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/ppc64: Clean up the boot-time settings display
At boot we display a bunch of low level settings which can be useful to
know, and can help to spot bugs when things are fundamentally
misconfigured.
At the moment they are very widely spaced, so that we can accommodate
the line:
ppc64_caches.dcache_line_size = 0xYY
But we only print that line when the cache line size is not 128, ie.
almost never, so it just makes the display look odd usually.
The ppc64_caches prefix is redundant so remove it, which means we can
align things a bit closer for the common case. While we're there
replace the last use of camelCase (physicalMemorySize), and use
phys_mem_size.
Li Zhong [Wed, 27 Aug 2014 09:34:01 +0000 (17:34 +0800)]
powerpc: some changes in numa_setup_cpu()
this patches changes some error handling logics in numa_setup_cpu(),
when cpu node is not found, so:
if the cpu is possible, but not present, -1 is kept in numa_cpu_lookup_table,
so later, if the cpu is added, we could set correct numa information for it.
if the cpu is present, then we set the first online node to
numa_cpu_lookup_table instead of 0 ( in case 0 might not be an online node? )
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Li Zhong [Wed, 27 Aug 2014 09:34:00 +0000 (17:34 +0800)]
powerpc: Only set numa node information for present cpus at boottime
As Nish suggested, it makes more sense to init the numa node informatiion
for present cpus at boottime, which could also avoid WARN_ON(1) in
numa_setup_cpu().
With this change, we also need to change the smp_prepare_cpus() to set up
numa information only on present cpus.
For those possible, but not present cpus, their numa information
will be set up after they are started, as the original code did before commit 2fabf084b6ad.
Li Zhong [Wed, 27 Aug 2014 09:33:59 +0000 (17:33 +0800)]
powerpc: Fix warning reported by verify_cpu_node_mapping()
With commit 2fabf084b6ad ("powerpc: reorder per-cpu NUMA information's
initialization"), during boottime, cpu_numa_callback() is called
earlier(before their online) for each cpu, and verify_cpu_node_mapping()
uses cpu_to_node() to check whether siblings are in the same node.
It skips the checking for siblings that are not online yet. So the only
check done here is for the bootcpu, which is online at that time. But
the per-cpu numa_node cpu_to_node() uses hasn't been set up yet (which
will be set up in smp_prepare_cpus()).
So I saw something like following reported:
[ 0.000000] CPU thread siblings 1/2/3 and 0 don't belong to the same
node!
As we don't actually do the checking during this early stage, so maybe
we could directly call numa_setup_cpu() in do_init_bootmem().
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Paul Mackerras [Tue, 2 Sep 2014 04:35:07 +0000 (14:35 +1000)]
powerpc: Split out instruction analysis part of emulate_step()
This splits out the instruction analysis part of emulate_step() into
a separate analyse_instr() function, which decodes the instruction,
but doesn't execute any load or store instructions. It does execute
integer instructions and branches which can be executed purely by
updating register values in the pt_regs struct. For other instructions,
it returns the instruction type and other details in a new
instruction_op struct. emulate_step() then uses that information
to execute loads, stores, cache operations, mfmsr, mtmsr[d], and
(on 64-bit) sc instructions.
The reason for doing this is so that the KVM code can use it instead
of having its own separate instruction emulation code. Possibly the
alignment interrupt handler could also use this.
Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Thu, 28 Aug 2014 08:40:47 +0000 (18:40 +1000)]
powerpc: Check flat device tree version at boot
In commit e6a6928c3ea1 "of/fdt: Convert FDT functions to use libfdt",
the kernel stopped supporting old flat device tree formats. The minimum
supported version is now 0x10.
There was a checking function added, early_init_dt_verify(), but it's
not called on powerpc.
The result is, if you boot with an old flat device tree, the kernel will
fail to parse it correctly, think you have no memory etc. and hilarity
ensues.
We can't really fix it, but we can at least catch the fact that the
device tree is in an unsupported format and panic(). We can't call
BUG(), it's too early.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Paul Mackerras [Tue, 2 Sep 2014 04:23:16 +0000 (14:23 +1000)]
powerpc/powernv: Don't call generic code on offline cpus
On PowerNV platforms, when a CPU is offline, we put it into nap mode.
It's possible that the CPU wakes up from nap mode while it is still
offline due to a stray IPI. A misdirected device interrupt could also
potentially cause it to wake up. In that circumstance, we need to clear
the interrupt so that the CPU can go back to nap mode.
In the past the clearing of the interrupt was accomplished by briefly
enabling interrupts and allowing the normal interrupt handling code
(do_IRQ() etc.) to handle the interrupt. This has the problem that
this code calls irq_enter() and irq_exit(), which call functions such
as account_system_vtime() which use RCU internally. Use of RCU is not
permitted on offline CPUs and will trigger errors if RCU checking is
enabled.
To avoid calling into any generic code which might use RCU, we adopt
a different method of clearing interrupts on offline CPUs. Since we
are on the PowerNV platform, we know that the system interrupt
controller is a XICS being driven directly (i.e. not via hcalls) by
the kernel. Hence this adds a new icp_native_flush_interrupt()
function to the native-mode XICS driver and arranges to call that
when an offline CPU is woken from nap. This new function reads the
interrupt from the XICS. If it is an IPI, it clears the IPI; if it
is a device interrupt, it prints a warning and disables the source.
Then it does the end-of-interrupt processing for the interrupt.
The other thing that briefly enabling interrupts did was to check and
clear the irq_happened flag in this CPU's PACA. Therefore, after
flushing the interrupt from the XICS, we also clear all bits except
the PACA_IRQ_HARD_DIS (interrupts are hard disabled) bit from the
irq_happened flag. The PACA_IRQ_HARD_DIS flag is set by power7_nap()
and is left set to indicate that interrupts are hard disabled. This
means we then have to ignore that flag in power7_nap(), which is
reasonable since it doesn't indicate that any interrupt event needs
servicing.
Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
of_device_ids (i.e. compatible strings and the respective data) are not
supposed to change at runtime. All functions working with of_device_ids
provided by <linux/of.h> work with const of_device_ids. This allows to
mark all struct of_device_id const, too.
While touching these line also put the __init annotation at the right
position where necessary.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
projects / karo-tx-linux.git / log