In the current kernel, the function flush_fp_to_thread() is not
dependent on CONFIG_PPC_FPU. So most invocations of this function
is not wrapped by CONFIG_PPC_FPU. Even through we don't really
save the FPRs to the thread struct if CONFIG_PPC_FPU is not enabled,
but there does have some runtime overhead such as the check for
tsk->thread.regs and preempt disable and enable. It really make
no sense to do that. So make it a nop when CONFIG_PPC_FPU is
disabled. Also remove the wrapped #ifdef CONFIG_PPC_FPU
when invoking this function.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In commit c6e6771b(powerpc: Introduce VSX thread_struct and CONFIG_VSX)
we add a invocation of flush_fp_to_thread() before copying the FPR or
VSR to users. But we already invoke the flush_fp_to_thread() in this
function. So remove one of them.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The only using of function disable_kernel_fp() was already dropped
in the commit 5daf9071 (powerpc: merge align.c).
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There are two invocations of do_mathemu() in traps.c. And the codes
in these two places are almost the same. Introduce a locale function
to eliminate the duplication. With this change we can also make sure
that in program_check_exception() the PPC_WARN_EMULATED is invoked for
the correctly emulated math instructions.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
By doing this we can make sure that the FPU state is only flushed to
the thread struct when it is really needed.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The Kconfig symbol 8XX_MINIMAL_FPEMU was removed in commit 968219fa33
("powerpc/8xx: Remove 8xx specific "minimal FPU emulation""). But that
commit didn't remove all code depending on that symbol. Do so now.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The udbg_16550 code, which we use for our early consoles and debug
backends was fairly messy. Especially for the debug consoles, it
would re-implement the "high level" getc/putc/poll functions for
each access method. It also had code to configure the UART but only
for the straight MMIO method.
This changes it to instead abstract at the register accessor level,
and have the various functions and configuration routines use these.
The result is simpler and slightly smaller code, and free support
for non-MMIO mapped PIO UARTs, which such as the ones that can be
present on a POWER 8 LPC bus.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This uses the hooks provided by CONFIG_PPC_INDIRECT_PIO to
implement a set of hooks for IO port access to use the LPC
bus via OPAL calls for the first 64K of IO space
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Remove the generic PPC_INDIRECT_IO and ensure we only add overhead
to the right accessors. IE. If only CONFIG_PPC_INDIRECT_PIO is set,
we don't add overhead to all MMIO accessors.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The SOFT_DISABLE_INTS seems an odd name for something that updates the
software state to be consistent with interrupts being hard disabled, so
rename SOFT_DISABLE_INTS with RECONCILE_IRQ_STATE to avoid this confusion.
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have a bunch of CONFIG_PPC_EARLY_DEBUG_* options that are intended
for bringup/debug only. They hard wire a machine specific udbg backend
very early on (before we even probe the platform), and use whatever
tricks are available on each machine/cpu to be able to get some kind
of output out there early on.
So far, on powermac with no serial ports, we have CONFIG_PPC_EARLY_DEBUG_BOOTX
to use the low-level btext engine on the screen, but it doesn't do much, at
least on 64-bit. It only really gets enabled after the platform has been
probed and the MMU enabled.
This adds a way to enable it much earlier. From prom_init.c (while still
running with Open Firmware), we grab the screen details and set things up
using the physical address of the frame buffer.
Then btext itself uses the "rm_ci" feature of the 970 processor (Real
Mode Cache Inhibited) to access it while in real mode.
We need to do a little bit of reorg of the btext code to inline things
better, in order to limit how much we touch memory while in this mode as
the consequences might be ... interesting.
This successfully allowed me to debug problems early on with the G5
(related to gold being broken vs. ppc64 kernels).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pci_read_bridge_bases() already checks if the PCI bus is root
bus or not, so we needn't do same check in pcibios_fixup_bus()
and just remove it.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Since 2002, the kernel has not saved VRSAVE on exception entry and
restored it on exit; rather, VRSAVE gets context-switched in _switch.
This means that when executing in process context in the kernel, the
userspace VRSAVE value is live in the VRSAVE register.
However, the signal code assumes that current->thread.vrsave holds
the current VRSAVE value, which is incorrect. Therefore, this
commit changes it to use the actual VRSAVE register instead. (It
still uses current->thread.vrsave as a temporary location to store
it in, as __get_user and __put_user can only transfer to/from a
variable, not an SPR.)
This also modifies the transactional memory code to save and restore
VRSAVE regardless of whether VMX is enabled in the MSR. This is
because accesses to VRSAVE are not controlled by the MSR.VEC bit,
but can happen at any time.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cell and PSeries both implemented their own versions of a
cpu_bootable smp_op which do the same thing (well, the PSeries
one has support for more than 2 threads). Copy the PSeries one
to generic code, and rename it smp_generic_cpu_bootable.
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
And now the function flush_icache_range() is just a wrapper which
only invoke the function __flush_icache_range() directly. So we
don't have reason to keep it anymore.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
In function flush_icache_range(), we use cpu_has_feature() to test
the feature bit of CPU_FTR_COHERENT_ICACHE. But this seems not optimal
for two reasons:
a) For ppc32, the function __flush_icache_range() already do this
check with the macro END_FTR_SECTION_IFSET.
b) Compare with the cpu_has_feature(), the method of using macro
END_FTR_SECTION_IFSET will not introduce any runtime overhead.
[And while at it, add the missing required isync] -- BenH
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Although the shared_proc field in the lppaca works today, it is
not architected. A shared processor partition will always have a non
zero yield_count so use that instead. Create a wrapper so users
don't have to know about the details.
In order for older kernels to continue to work on KVM we need
to set the shared_proc bit. While here, remove the ugly bitfield.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Fix a sparse warning about force_32bit_msi being a one bit bitfield.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Address some of the trivial sparse warnings in arch/powerpc.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Normally when we haven't implemented an alignment handler for
a load or store instruction the process will be terminated.
The alignment handler uses the DSISR (or a pseudo one) to locate
the right handler. Unfortunately ldbrx and stdbrx overlap lfs and
stfs so we incorrectly think ldbrx is an lfs and stdbrx is an
stfs.
This bug is particularly nasty - instead of terminating the
process we apply an incorrect fixup and continue on.
With more and more overlapping instructions we should stop
creating a pseudo DSISR and index using the instruction directly,
but for now add a special case to catch ldbrx/stdbrx.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
p_toc is an 8 byte relative offset to the TOC that we place in the
text section. This means it is only 4 byte aligned where it should
be 8 byte aligned. Add an explicit alignment.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If a transaction is rolled back, the Target Address Register (TAR), Processor
Priority Register (PPR) and Data Stream Control Register (DSCR) should be
restored to the checkpointed values before the transaction began. Any changes
to these SPRs inside the transaction should not be visible in the abort
handler.
Currently Linux doesn't save or restore the checkpointed TAR, PPR or DSCR. If
we preempt a processes inside a transaction which has modified any of these, on
process restore, that same transaction may be aborted we but we won't see the
checkpointed versions of these SPRs.
This adds checkpointed versions of these SPRs to the thread_struct and adds the
save/restore of these three SPRs to the treclaim/trechkpt code.
Without this if any of these SPRs are modified during a transaction, users may
incorrectly see a speculated SPR value even if the transaction is aborted.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This moves us to save the Target Address Register (TAR) a earlier in
__switch_to. It introduces a new function save_tar() to do this.
We need to save the TAR earlier as we will overwrite it in the transactional
memory reclaim/recheckpoint path. We are going to do this in a subsequent
patch which will fix saving the TAR register when it's modified inside a
transaction.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
POWER8 allows the DSCR to be accessed directly from userspace via a new SPR
number 0x3 (Rather than 0x11. DSCR SPR number 0x11 is still used on POWER8 but
like POWER7, is only accessible in HV and OS modes). Currently, we allow this
by setting H/FSCR DSCR bit on boot.
Unfortunately this doesn't work, as the kernel needs to see the DSCR change so
that it knows to no longer restore the system wide version of DSCR on context
switch (ie. to set thread.dscr_inherit).
This clears the H/FSCR DSCR bit initially. If a process then accesses the DSCR
(via SPR 0x3), it'll trap into the kernel where we set thread.dscr_inherit in
facility_unavailable_exception().
We also change _switch() so that we set or clear the H/FSCR DSCR bit based on
the thread.dscr_inherit.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently if we take hypervisor facility unavaliable (from 0xf80/0x4f80) we
mark it as an OS facility unavaliable (0xf60) as the two share the same code
path.
The becomes a problem in facility_unavailable_exception() as we aren't able to
see the hypervisor facility unavailable exceptions.
Below fixes this by duplication the required macros.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: <stable@vger.kernel.org> [v3.10]
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The procfs entry for global statistics has been missed on PowerNV
platform and the patch is going to add that.
Signed-off-by: Mike Qiu <qiudayu@linux.vnet.ibm.com>
Acked-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At console init, when the kernel tries to flush the log buffer
the ePAPR byte-channel based console write fails silently,
losing the buffered messages.
This happens because The ePAPR para-virtualization init isn't
done early enough so that the hcall instruction to be set,
causing the byte-channel write hcall to be a nop.
To fix, change the ePAPR para-virt init to use early device
tree functions and move it in early init.
Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
There are 6 counters in e6500 core instead of 4 in e500 core.
Signed-off-by: Lijun Pan <Lijun.Pan@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Back in commit 89713ed "Add timer, performance monitor and machine check
counts to /proc/interrupts" we added a count of PMU interrupts to the
output of /proc/interrupts.
At the time we named them "CNT" to match x86.
However in commit 89ccf46 "Rename 'performance counter interrupt'", the
x86 guys renamed theirs from "CNT" to "PMI".
Arguably changing the name could break someone's script, but I think the
chance of that is minimal, and it's preferable to have a name that 1) is
somewhat meaningful, and 2) matches x86.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This problem belongs to the core synchronization issues.
The cpu1 already updated spin_table values, but bootcore cannot get
this value in time.
After bootcpu hibiernation restore the pages. we are now running
with the kernel data of the old kernel fully restored. if we reset
the non-bootcpus that will be reset cache(tlb), the non-bootcpus
will get new address(map virtual and physical address spaces).
but bootcpu tlb cache still use boot kernel data, so we need to
invalidate the bootcpu tlb cache make it to get new main memory data.
log:
Enabling non-boot CPUs ...
smp_85xx_kick_cpu: timeout waiting for core 1 to reset
smp: failed starting cpu 1 (rc -2)
Error taking CPU1 up: -2
Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Reviewed-by: Anton Vorontsov <anton@enomsg.org>
[scottwood@freescale.com: reworded code comment for clarity]
Signed-off-by: Scott Wood <scottwood@freescale.com>
A PCIe erratum of mpc85xx may causes a core hang when a link of PCIe
goes down. when the link goes down, Non-posted transactions issued
via the ATMU requiring completion result in an instruction stall.
At the same time a machine-check exception is generated to the core
to allow further processing by the handler. We implements the handler
which skips the instruction caused the stall.
This patch depends on patch:
powerpc/85xx: Add platform_device declaration to fsl_pci.h
Signed-off-by: Zhao Chenhui <b35336@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Liu Shuo <soniccat.liu@gmail.com>
Signed-off-by: Jia Hongtao <hongtao.jia@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Unlike the other general-purpose SPRs, SPRG3 can be read by usermode
code, and is used in recent kernels to store the CPU and NUMA node
numbers so that they can be read by VDSO functions. Thus we need to
load the guest's SPRG3 value into the real SPRG3 register when entering
the guest, and restore the host's value when exiting the guest. We don't
need to save the guest SPRG3 value when exiting the guest as usermode
code can't modify SPRG3.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
On some PAE architectures, the entire range of physical memory could reside
outside the 32-bit limit. These systems need the ability to specify the
initrd location using 64-bit numbers.
This patch globally modifies the early_init_dt_setup_initrd_arch() function to
use 64-bit numbers instead of the current unsigned long.
There has been quite a bit of debate about whether to use u64 or phys_addr_t.
It was concluded to stick to u64 to be consistent with rest of the device
tree code. As summarized by Geert, "The address to load the initrd is decided
by the bootloader/user and set at that point later in time. The dtb should not
be tied to the kernel you are booting"
More details on the discussion can be found here:
https://lkml.org/lkml/2013/6/20/690https://lkml.org/lkml/2012/9/13/544
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
The patch introduces flag EEH_DEV_SYSFS to keep track that the sysfs
entries for the corresponding EEH device (then PCI device) has been
added or removed, in order to avoid race condition.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
While restoring BARs for one specific PCI device, the pci_dev
instance should have been released. So it's not reliable to use
the pci_dev instance on restoring BARs. However, we still need
some information (e.g. PCIe capability position, header type) from
the pci_dev instance. So we have to store those information to
EEH device in advance.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When EEH error happens to one specific PE, some devices with drivers
supporting EEH won't except hotplug on the device. However, there
might have other deivces without driver, or with driver without EEH
support. For the case, we need do partial hotplug in order to make
sure that the PE becomes absolutely quite during reset. Otherise,
the PE reset might fail and leads to failure of error recovery.
The current code doesn't handle that 'mixed' case properly, it either
uses the error callbacks to the drivers, or tries hotplug, but doesn't
handle a PE (EEH domain) composed of a combination of the two.
The patch intends to support so-called "partial" hotplug for EEH:
Before we do reset, we stop and remove those PCI devices without
EEH sensitive driver. The corresponding EEH devices are not detached
from its PE, but with special flag. After the reset is done, those
EEH devices with the special flag will be scanned one by one.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When EEH error happens to one specific PE, the device drivers
of its attached EEH devices (PCI devices) are checked to see
the further action: reset with complete hotplug, or reset without
hotplug. However, that's not enough for those PCI devices whose
drivers can't support EEH, or those PCI devices without driver.
So we need do so-called "partial hotplug" on basis of PCI devices.
In the situation, part of PCI devices of the specific PE are
unplugged and plugged again after PE reset.
The patch changes pcibios_add_pci_devices() so that it can support
full hotplug and so-called "partial" hotplug based on device-tree
or real hardware. It's notable that pci_of_scan.c has been changed
for a bit in order to support the "partial" hotplug based on dev-tree.
Most of the generic code already supports that, we just need to
plumb it properly on our side.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, we're trasversing the EEH devices list using list_for_each_entry().
That's not safe enough because the EEH devices might be removed from
its parent PE while doing iteration. The patch replaces that with
list_for_each_entry_safe().
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When we do normal hotplug, the PE (shadow EEH structure) shouldn't be
kept around.
However, we need to keep it if the hotplug an artifial one caused by
EEH errors recovery.
Since we remove EEH device through the PCI hook pcibios_release_device(),
the flag "purge_pe" passed to various functions is meaningless. So the patch
removes the meaningless flag and introduce new flag "EEH_PE_KEEP"
to save the PE while doing hotplug during EEH error recovery.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Make some functions public in order to support hotplug on either specific
PCI bus or PCI device in future.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We will rely on pcibios_release_device() to remove the EEH cache
and unbind EEH device for the specific PCI device. So we shouldn't
hold the reference to the PCI device from EEH cache and EEH device.
Otherwise, pcibios_release_device() won't be called as we expected.
The patch removes the reference to the PCI device in EEH core.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Module CRCs are implemented as absolute symbols that get resolved by
a linker script. We build an intermediate .o that contains an
unresolved symbol for each CRC. genksysms parses this .o, calculates
the CRCs and writes a linker script that "resolves" the symbols to
the calculated CRC.
Unfortunately the ppc64 relocatable kernel sees these CRCs as symbols
that need relocating and relocates them at boot. Commit d4703aef
(module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y)
added a hook to reverse the bogus relocations. Part of this patch
created a symbol at 0x0:
# head -2 /proc/kallsyms
0000000000000000 T reloc_start
c000000000000000 T .__start
This reloc_start symbol is causing lots of confusion to perf. It
thinks reloc_start is a massive function that stretches from 0x0 to
0xc000000000000000 and we get various cryptic errors out of perf,
including:
problem incrementing symbol count, skipping event
This patch removes the reloc_start linker script label and instead
defines it as PHYSICAL_START. We also need to wrap it with
CONFIG_PPC64 because the ppc32 kernel can set a non zero
PHYSICAL_START at compile time and we wouldn't want to subtract
it from the CRCs in that case.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@kernel.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
POWER8 comes with two different PVRs. This patch enables the additional
PVR in the cputable.
The existing entry (PVR=0x4b) is renamed to POWER8E and the new entry
(PVR=0x4d) is given POWER8.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This reverts commit 07fa7a0a8a ("hw_breakpoints: Fix racy access to
ptrace breakpoints") and removes ptrace_get/put_breakpoints() added by
other commits.
The patch was fine but we can no longer race with SIGKILL after commit
9899d11f65 ("ptrace: ensure arch_ptrace/ptrace_request can never race
with SIGKILL"), the __TASK_TRACED tracee can't be woken up and
->ptrace_bps[] can't go away.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
