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2525 commits

Author SHA1 Message Date
Matt Evans
e8e5c2155b powerpc/kexec: Fix orphaned offline CPUs across kexec
When CPU hotplug is used, some CPUs may be offline at the time a kexec is
performed.  The subsequent kernel may expect these CPUs to be already running,
and will declare them stuck.  On pseries, there's also a soft-offline (cede)
state that CPUs may be in; this can also cause problems as the kexeced kernel
may ask RTAS if they're online -- and RTAS would say they are.  The CPU will
either appear stuck, or will cause a crash as we replace its cede loop beneath
it.

This patch kicks each present offline CPU awake before the kexec, so that
none are forever lost to these assumptions in the subsequent kernel.

Now, the behaviour is that all available CPUs that were offlined are now
online & usable after the kexec.  This mimics the behaviour of a full reboot
(on which all CPUs will be restarted).

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 15:05:22 +10:00
Matt Evans
e2f7f73717 powerpc/kexec: Add to and tidy debug/comments in machine_kexec64.c
Tidies some typos, KERN_INFO-ise an info msg, and add a debug msg showing
when the final sequence starts.

Also adds a comment to kexec_prepare_cpus_wait() to make note of a possible
problem; the need for kexec to deal with CPUs that failed to originally start
up.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 15:05:21 +10:00
Michael Neuling
2c48a7d615 powerpc: Print decimal values in prom_init.c
Currently we look pretty stupid when printing out a bunch of things in
prom_init.c.  eg.

  Max number of cores passed to firmware: 0x0000000000000080

So I've change this to print in decimal:

  Max number of cores passed to firmware: 128 (NR_CPUS = 256)

This required adding a prom_print_dec() function and changing some
prom_printk() calls from %x to %lu.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 15:05:20 +10:00
Tiejun Chen
d77cb21b57 powerpc/smp: remove the incorrect decrementer initial codes for AP
We already defined start_cpu_decrementer() to invoke decrementer for AP as
the following path:

start_secondary() -> secondary_cpu_time_init() -> start_cpu_decrementer()

So remove these incorrect codes introduced from commit:
e7f75ad0 powerpc/47x: Base ppc476 support

And actually we really should not enable decrementer before calling set_dec().

Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 14:56:31 +10:00
Neil Horman
67238fb721 powerpc: Add vmcoreinfo symbols to allow makdumpfile to filter core files properly
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

 machine_kexec.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 14:56:31 +10:00
Matthew McClintock
bbc8e30f17 powerpc/crashdump: Fix issues with kexec and 36bit physical addr
Fix sizes of variables so correct values are exported via /proc.
Cast variable in comparison to avoid compiler error.

Signed-off-by: Matthew McClintock <msm@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 14:56:30 +10:00
Matt Evans
fc53b4202e powerpc/kexec: Switch to a static PACA on the way out
With dynamic PACAs, the kexecing CPU's PACA won't lie within the kernel
static data and there is a chance that something may stomp it when preparing
to kexec.  This patch switches this final CPU to a static PACA just before
we pull the switch.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-31 14:56:30 +10:00
Benjamin Herrenschmidt
7e3f36c3e1 Merge commit 'jwb/next' into next 2010-07-30 15:02:32 +10:00
Lee Nipper
ff34910396 powerpc/40x: Distinguish AMCC PowerPC 405EX and 405EXr correctly
The recent AMCC 405EX Rev D without Security uses a PVR value
that matches the old 405EXr Rev A/B with Security.
The 405EX Rev D without Security would be shown
incorrectly as an 405EXr. The pvr_mask of 0xffff0004
is no longer sufficient to distinguish the 405EX from 405EXr.

This patch replaces 2 entries in the cpu_specs table
and adds 8 more, each using pvr_mask of 0xffff000f
and appropriate pvr_value to distinguish the AMCC
PowerPC 405EX and 405EXr instances.
The cpu_name for these entries now includes the
Rev, in similar fashion to the 440GX.

Signed-off-by: Lee Nipper <lee.nipper@gmail.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2010-07-26 09:07:24 -04:00
Benjamin Herrenschmidt
ff82c319e6 powerpc/book3e: Fix single step when using HW page tables
We patch the TLB miss exception vectors to point to alternate
functions when using HW page table on BookE.

However, we were patching in a new branch in the first instruction
of the exception handler instead of the second one, thus overriding
the nop that is in the first instruction.

This cause problems when single stepping as we rely on that nop for
the single step to stop properly within the exception vector range
rather than on the target of the branch.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-14 14:13:51 +10:00
Benjamin Herrenschmidt
34d97e07cc powerpc/book3e: Add generic 64-bit idle powersave support
We use a similar technique to ppc32: We set a thread local flag
to indicate that we are about to enter or have entered the stop
state, and have fixup code in the async interrupt entry code that
reacts to this flag to make us return to a different location
(sets NIP to LINK in our case).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
--
v2. Fix lockdep bug
    Re-mask interrupts when coming back from idle
2010-07-14 14:13:18 +10:00
Michael Ellerman
850f22d568 powerpc/book3e: Resend doorbell exceptions to ourself
If we are soft disabled and receive a doorbell exception we don't process
it immediately. This means we need to check on the way out of irq restore
if there are any doorbell exceptions to process.

The problem is at that point we don't know what our regs are, and that
in turn makes xmon unhappy. To workaround the problem, instead of checking
for and processing doorbells, we check for any doorbells and if there were
any we send ourselves another.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 16:11:19 +10:00
David Gibson
0e37d25950 powerpc/book3e: Use set_irq_regs() in the msgsnd/msgrcv IPI path
include/asm-generic/irq_regs.h declares per-cpu irq_regs variables and
get_irq_regs() and set_irq_regs() helper functions to maintain them.
These can be used to access the proper pt_regs structure related to the
current interrupt entry (if any).

In the powerpc arch code, this is used to maintain irq regs on
decrementer and external interrupt exceptions.  However, for the
doorbell exceptions used by the msgsnd/msgrcv IPI mechanism of newer
BookE CPUs, the irq_regs are not kept up to date.

In particular this means that xmon will not work properly on SMP,
because the secondary xmon instances started by IPI will blow up when
they cannot retrieve the irq regs.

This patch fixes the problem by adding calls to maintain the irq regs
across doorbell exceptions.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 16:11:18 +10:00
Benjamin Herrenschmidt
89c81797d4 powerpc/book3e: Hookup doorbells exceptions on 64-bit Book3E
Note that critical doorbells are an unimplemented stub just like
other critical or machine check handlers, since we haven't done
support for "levelled" exceptions yet.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 16:11:17 +10:00
Benjamin Herrenschmidt
e8775d4aa1 powerpc/book3e: Don't re-trigger decrementer on lazy irq restore
The decrementer on BookE acts as a level interrupt and doesn't
need to be re-triggered when going negative. It doesn't go
negative anyways (unless programmed to auto-reload with a
negative value) as it stops when reaching 0.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 16:11:09 +10:00
Benjamin Herrenschmidt
b9f1cd71db powerpc/book3e: More doorbell cleanups. Sample the PIR register
The doorbells use the content of the PIR register to match messages
from other CPUs. This may or may not be the same as our linux CPU
number, so using that as the "target" is no right.

Instead, we sample the PIR register at boot on every processor
and use that value subsequently when sending IPIs.

We also use a per-cpu message mask rather than a global array which
should limit cache line contention.

Note: We could use the CPU number in the device-tree instead of
the PIR register, as they are supposed to be equivalent. This
might prove useful if doorbells are to be used to kick CPUs out
of FW at boot time, thus before we can sample the PIR. This is
however not the case now and using the PIR just works.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 15:29:53 +10:00
Benjamin Herrenschmidt
e3145b387a powerpc/book3e: Move doorbell_exception from traps.c to dbell.c
... where it belongs

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 15:25:18 +10:00
Benjamin Herrenschmidt
a2e198116f powerpc/book3e: Hack to get gdb moving along on Book3E 64-bit
Our handling of debug interrupts on Book3E 64-bit is not quite
the way it should be just yet. This is a workaround to let gdb
work at least for now. We ensure that when context switching,
we set the appropriate DBCR0 value for the new task. We also
make sure that we turn off MSR[DE] within the kernel, and set
it as part of the bits that get set when going back to userspace.

In the long run, we will probably set the userspace DBCR0 on the
exception exit code path and ensure we have some proper kernel
value to set on the way into the kernel, a bit like ppc32 does,
but that will take more work.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 15:24:47 +10:00
Martyn Welch
540c6c392f powerpc: Add i8042 keyboard and mouse irq parsing
Currently the irqs for the i8042, which historically provides keyboard and
mouse (aux) support, is hardwired in the driver rather than parsing the
dts.  This patch modifies the powerpc legacy IO code to attempt to parse
the device tree for this information, failing back to the hardcoded values
if it fails.

Signed-off-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:28:33 +10:00
Anton Blanchard
ae01f84b93 powerpc: Optimise per cpu accesses on 64bit
Now we dynamically allocate the paca array, it takes an extra load
whenever we want to access another cpu's paca. One place we do that a lot
is per cpu variables. A simple example:

DEFINE_PER_CPU(unsigned long, vara);
unsigned long test4(int cpu)
{
	return per_cpu(vara, cpu);
}

This takes 4 loads, 5 if you include the actual load of the per cpu variable:

    ld r11,-32760(r30)  # load address of paca pointer
    ld r9,-32768(r30)   # load link address of percpu variable
    sldi r3,r29,9       # get offset into paca (each entry is 512 bytes)
    ld r0,0(r11)        # load paca pointer
    add r3,r0,r3        # paca + offset
    ld r11,64(r3)       # load paca[cpu].data_offset

    ldx r3,r9,r11       # load per cpu variable

If we remove the ppc64 specific per_cpu_offset(), we get the generic one
which indexes into a statically allocated array. This removes one load and
one add:

    ld r11,-32760(r30)  # load address of __per_cpu_offset
    ld r9,-32768(r30)   # load link address of percpu variable
    sldi r3,r29,3       # get offset into __per_cpu_offset (each entry 8 bytes)
    ldx r11,r11,r3      # load __per_cpu_offset[cpu]

    ldx r3,r9,r11       # load per cpu variable

Having all the offsets in one array also helps when iterating over a per cpu
variable across a number of cpus, such as in the scheduler. Before we would
need to load one paca cacheline when calculating each per cpu offset. Now we
have 16 (128 / sizeof(long)) per cpu offsets in each cacheline.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:28:30 +10:00
Brian King
8fe93f8d85 powerpc/pseries: Migration code reorganization / hibernation prep
Partition hibernation will use some of the same code as is
currently used for Live Partition Migration. This function
further abstracts this code such that code outside of rtas.c
can utilize it. It also changes the error field in the suspend
me data structure to be an atomic type, since it is set and
checked on different cpus without any barriers or locking.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:26:17 +10:00
Paul Mackerras
c1aa687d49 powerpc: Clean up obsolete code relating to decrementer and timebase
Since the decrementer and timekeeping code was moved over to using
the generic clockevents and timekeeping infrastructure, several
variables and functions have been obsolete and effectively unused.
This deletes them.

In particular, wakeup_decrementer() is no longer needed since the
generic code reprograms the decrementer as part of the process of
resuming the timekeeping code, which happens during sysdev resume.
Thus the wakeup_decrementer calls in the suspend_enter methods for
52xx platforms have been removed.  The call in the powermac cpu
frequency change code has been replaced by set_dec(1), which will
cause a timer interrupt as soon as interrupts are enabled, and the
generic code will then reprogram the decrementer with the correct
value.

This also simplifies the generic_suspend_en/disable_irqs functions
and makes them static since they are not referenced outside time.c.
The preempt_enable/disable calls are removed because the generic
code has disabled all but the boot cpu at the point where these
functions are called, so we can't be moved to another cpu.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:26:16 +10:00
Paul Mackerras
8fd63a9ea7 powerpc: Rework VDSO gettimeofday to prevent time going backwards
Currently it is possible for userspace to see the result of
gettimeofday() going backwards by 1 microsecond, assuming that
userspace is using the gettimeofday() in the VDSO.  The VDSO
gettimeofday() algorithm computes the time in "xsecs", which are
units of 2^-20 seconds, or approximately 0.954 microseconds,
using the algorithm

	now = (timebase - tb_orig_stamp) * tb_to_xs + stamp_xsec

and then converts the time in xsecs to seconds and microseconds.

The kernel updates the tb_orig_stamp and stamp_xsec values every
tick in update_vsyscall().  If the length of the tick is not an
integer number of xsecs, then some precision is lost in converting
the current time to xsecs.  For example, with CONFIG_HZ=1000, the
tick is 1ms long, which is 1048.576 xsecs.  That means that
stamp_xsec will advance by either 1048 or 1049 on each tick.
With the right conditions, it is possible for userspace to get
(timebase - tb_orig_stamp) * tb_to_xs being 1049 if the kernel is
slightly late in updating the vdso_datapage, and then for stamp_xsec
to advance by 1048 when the kernel does update it, and for userspace
to then see (timebase - tb_orig_stamp) * tb_to_xs being zero due to
integer truncation.  The result is that time appears to go backwards
by 1 microsecond.

To fix this we change the VDSO gettimeofday to use a new field in the
VDSO datapage which stores the nanoseconds part of the time as a
fractional number of seconds in a 0.32 binary fraction format.
(Or put another way, as a 32-bit number in units of 0.23283 ns.)
This is convenient because we can use the mulhwu instruction to
convert it to either microseconds or nanoseconds.

Since it turns out that computing the time of day using this new field
is simpler than either using stamp_xsec (as gettimeofday does) or
stamp_xtime.tv_nsec (as clock_gettime does), this converts both
gettimeofday and clock_gettime to use the new field.  The existing
__do_get_tspec function is converted to use the new field and take
a parameter in r7 that indicates the desired resolution, 1,000,000
for microseconds or 1,000,000,000 for nanoseconds.  The __do_get_xsec
function is then unused and is deleted.

The new algorithm is

	now = ((timebase - tb_orig_stamp) << 12) * tb_to_xs
		+ (stamp_xtime_seconds << 32) + stamp_sec_fraction

with 'now' in units of 2^-32 seconds.  That is then converted to
seconds and either microseconds or nanoseconds with

	seconds = now >> 32
	partseconds = ((now & 0xffffffff) * resolution) >> 32

The 32-bit VDSO code also makes a further simplification: it ignores
the bottom 32 bits of the tb_to_xs value, which is a 0.64 format binary
fraction.  Doing so gets rid of 4 multiply instructions.  Assuming
a timebase frequency of 1GHz or less and an update interval of no
more than 10ms, the upper 32 bits of tb_to_xs will be at least
4503599, so the error from ignoring the low 32 bits will be at most
2.2ns, which is more than an order of magnitude less than the time
taken to do gettimeofday or clock_gettime on our fastest processors,
so there is no possibility of seeing inconsistent values due to this.

This also moves update_gtod() down next to its only caller, and makes
update_vsyscall use the time passed in via the wall_time argument rather
than accessing xtime directly.  At present, wall_time always points to
xtime, but that could change in future.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-09 11:26:16 +10:00
Benjamin Herrenschmidt
5f07aa7524 Merge commit 'paulus-perf/master' into next 2010-07-09 11:25:48 +10:00
Paul E. McKenney
c2be05481f powerpc: Fix default_machine_crash_shutdown #ifdef botch
crash_kexec_wait_realmode() is defined only if CONFIG_PPC_STD_MMU_64
and CONFIG_SMP, but is called if CONFIG_PPC_STD_MMU_64 even if !CONFIG_SMP.
Fix the conditional compilation around the invocation.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-08 18:11:45 +10:00
Johannes Berg
3cd8519248 powerpc: Fix logic error in fixup_irqs
When SPARSE_IRQ is set, irq_to_desc() can
return NULL. While the code here has a
check for NULL, it's not really correct.
Fix it by separating the check for it.

This fixes CPU hot unplug for me.

Reported-by: Alastair Bridgewater <alastair.bridgewater@gmail.com>
Cc: stable@kernel.org [2.6.32+]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-08 18:11:44 +10:00
Anton Blanchard
33ad5e4b6c powerpc: Linux cannot run with 0 cores
If we configure with CONFIG_SMP=n or set NR_CPUS less than the number of
SMT threads we will set the max cores property to 0 in the
ibm,client-architecture-support structure. On new versions of firmware that
understand this property it obliges and terminates our partition.

Use DIV_ROUND_UP so we handle not only the CONFIG_SMP=n case but also the
case where NR_CPUS isn't a multiple of the number of SMT threads.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-08 18:11:42 +10:00
Stephen Rothwell
5afd878a95 powerpc: Fix compile errors in prom_init_check for gcc 4.5
Just whitelist these extra compiler generated symbols.
Fixes these errors:

Error: External symbol '_restgpr0_14' referenced from prom_init.c
Error: External symbol '_restgpr0_20' referenced from prom_init.c
Error: External symbol '_restgpr0_22' referenced from prom_init.c
Error: External symbol '_restgpr0_24' referenced from prom_init.c
Error: External symbol '_restgpr0_25' referenced from prom_init.c
Error: External symbol '_restgpr0_26' referenced from prom_init.c
Error: External symbol '_restgpr0_27' referenced from prom_init.c
Error: External symbol '_restgpr0_28' referenced from prom_init.c
Error: External symbol '_restgpr0_29' referenced from prom_init.c
Error: External symbol '_restgpr0_31' referenced from prom_init.c
Error: External symbol '_savegpr0_14' referenced from prom_init.c
Error: External symbol '_savegpr0_20' referenced from prom_init.c
Error: External symbol '_savegpr0_22' referenced from prom_init.c
Error: External symbol '_savegpr0_24' referenced from prom_init.c
Error: External symbol '_savegpr0_25' referenced from prom_init.c
Error: External symbol '_savegpr0_26' referenced from prom_init.c
Error: External symbol '_savegpr0_27' referenced from prom_init.c
Error: External symbol '_savegpr0_28' referenced from prom_init.c
Error: External symbol '_savegpr0_29' referenced from prom_init.c
Error: External symbol '_savegpr0_31' referenced from prom_init.c

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-08 18:11:39 +10:00
Matt Evans
219a92a4c4 powerpc/perf_event: Fix for power_pmu_disable()
When power_pmu_disable() removes the given event from a particular index into
cpuhw->event[], it shuffles down higher event[] entries.  But, this array is
paired with cpuhw->events[] and cpuhw->flags[] so should shuffle them
similarly.

If these arrays get out of sync, code such as power_check_constraints() will
fail.  This caused a bug where events were temporarily disabled and then failed
to be re-enabled; subsequent code tried to write_pmc() with its (disabled) idx
of 0, causing a message "oops trying to write PMC0".  This triggers this bug on
POWER7, running a miss-heavy test:

  perf record -e L1-dcache-load-misses -e L1-dcache-store-misses ./misstest

Signed-off-by: Matt Evans <matt@ozlabs.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-07-08 18:11:37 +10:00
Paul Mackerras
d09ec73871 powerpc, hw_breakpoint: Tell generic code we have no instruction breakpoints
At present, hw_breakpoint_slots() returns 1 regardless of what
type of breakpoint is specified in the type argument.  Since we
don't define CONFIG_HAVE_MIXED_BREAKPOINTS_REGS, there are
separate values for TYPE_INST and TYPE_DATA, and hw_breakpoint_slots()
returns 1 for both, effectively advertising instruction breakpoint
support which doesn't exist.

This fixes it by making hw_breakpoint_slots return 1 for TYPE_DATA
and 0 for TYPE_INST.  This moves hw_breakpoint_slots() from the
powerpc hw_breakpoint.h to hw_breakpoint.c because the definitions
of TYPE_INST and TYPE_DATA aren't available in <asm/hw_breakpoint.h>.
They are defined in <linux/hw_breakpoint.h> but we can't include
that header in <asm/hw_breakpoint.h>, and nor can we rely on
<linux/hw_breakpoint.h> being included before <asm/hw_breakpoint.h>.
Since hw_breakpoint_slots() is only called at boot time, there is
no performance impact from making it a real function rather than
a static inline.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-30 13:54:58 +10:00
Paul Mackerras
76b0f13376 powerpc, hw_breakpoint: Cooperate better with other single-steppers
The code we had to clear the MSR_SE bit was not doing anything because
the caller (ultimately single_step_exception() in traps.c) had already
cleared.  Instead of trying to leave MSR_SE set if the TIF_SINGLESTEP
flag is set (which indicates that the process is being single-stepped
by ptrace), we instead return NOTIFY_DONE in that case, which means
the caller will generate a SIGTRAP for the process.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-23 15:46:55 +10:00
Paul Mackerras
574cb24899 powerpc, hw_breakpoint: Fix off-by-one in checking access address
The code would accept an access to an address one byte past the end
of the requested range as legitimate, due to having a "<=" rather than
a "<".  This fixes that and cleans up the code a bit.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-23 15:42:43 +10:00
K.Prasad
e3e94084ad powerpc, hw_breakpoint: Discard extraneous interrupt due to accesses outside symbol length
Many a times, the requested breakpoint length can be less than the
fixed breakpoint length i.e. 8 bytes supported by PowerPC 64-bit
server (Book III S) processors.  This could lead to extraneous
interrupts resulting in false breakpoint notifications.  This
detects and discards such interrupts for non-ptrace requests.
We don't change ptrace behaviour to avoid breaking compatability.

[Suggestion from Paul Mackerras <paulus@samba.org> to add a new flag in
'struct arch_hw_breakpoint' to identify extraneous interrupts]

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-22 19:40:51 +10:00
K.Prasad
06532a6743 powerpc, hw_breakpoint: Enable hw-breakpoints while handling intervening signals
A signal delivered between a hw_breakpoint_handler() and the
single_step_dabr_instruction() will not have the breakpoint active
while the signal handler is running -- the signal delivery will
set up a new MSR value which will not have MSR_SE set, so we
won't get the signal step interrupt until and unless the signal
handler returns (which it may never do).

To fix this, we restore the breakpoint when delivering a signal --
we clear the MSR_SE bit and set the DABR again.  If the signal
handler returns, the DABR interrupt will occur again when the
instruction that we were originally trying to single-step gets
re-executed.

[Paul Mackerras <paulus@samba.org> pointed out the need to do this.]

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-22 19:40:50 +10:00
K.Prasad
2538c2d08f powerpc, hw_breakpoint: Handle concurrent alignment interrupts
If an alignment interrupt occurs on an instruction that is being
single-stepped, the alignment interrupt handler currently handles
the single-step condition by unconditionally sending a SIGTRAP to
the process.  Other synchronous interrupts that result in the
instruction being emulated do likewise.

With hw_breakpoint support, the hw_breakpoint code needs to be able
to intercept these single-step events as well as those where the
instruction executes normally and a trace interrupt happens.

Fix this by making emulate_single_step() use the existing
single_step_exception() function instead of calling _exception()
directly.  We then make single_step_exception() use the abstracted
clear_single_step() rather than clearing bits in the MSR image
directly so that emulate_single_step() will continue to work
correctly on Book 3E processors.

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-22 19:40:50 +10:00
K.Prasad
5aae8a5370 powerpc, hw_breakpoints: Implement hw_breakpoints for 64-bit server processors
Implement perf-events based hw-breakpoint interfaces for PowerPC
64-bit server (Book III S) processors.  This allows access to a
given location to be used as an event that can be counted or
profiled by the perf_events subsystem.

This is done using the DABR (data breakpoint register), which can
also be used for process debugging via ptrace.  When perf_event
hw_breakpoint support is configured in, the perf_event subsystem
manages the DABR and arbitrates access to it, and ptrace then
creates a perf_event when it is requested to set a data breakpoint.

[Adopted suggestions from Paul Mackerras <paulus@samba.org> to
- emulate_step() all system-wide breakpoints and single-step only the
  per-task breakpoints
- perform arch-specific cleanup before unregistration through
  arch_unregister_hw_breakpoint()
]

Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-22 19:40:50 +10:00
Milton Miller
bd2b64a12b powerpc: rtas_flash needs to use rtas_data_buf
When trying to flash a machine via the update_flash command, Anton received the
following error:

    Restarting system.
    FLASH: kernel bug...flash list header addr above 4GB

The code in question has a comment that the flash list should be in
the kernel data and therefore under 4GB:

        /* NOTE: the "first" block list is a global var with no data
         * blocks in the kernel data segment.  We do this because
         * we want to ensure this block_list addr is under 4GB.
         */

Unfortunately the Kconfig option is marked tristate which means the variable
may not be in the kernel data and could be above 4GB.

Instead of relying on the data segment being below 4GB, use the static
data buffer allocated by the kernel for use by rtas.  Since we don't
use the header struct directly anymore, convert it to a simple pointer.

Reported-By: Anton Blanchard <anton@samba.org>
Signed-Off-By: Milton Miller <miltonm@bga.com
Tested-By: Anton Blanchard <anton@samba.org>

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-15 15:02:37 +10:00
Christoph Hellwig
f1ba9a5b2a powerpc: Unconditionally enabled irq stacks
Irq stacks provide an essential protection from stack overflows through
external interrupts, at the cost of two additionals stacks per CPU.

Enable them unconditionally to simplify the kernel build and prevent
people from accidentally disabling them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-15 15:02:37 +10:00
Matt Evans
b636f1379e powerpc/kexec: Wait for online/possible CPUs only.
kexec_perpare_cpus_wait() iterates i through NR_CPUS to check
paca[i].kexec_state of each to make sure they have quiesced.
However now we have dynamic PACA allocation, paca[NR_CPUS] is not necessarily
valid and we overrun the array;  spurious "cpu is not possible, ignoring"
errors result.  This patch iterates for_each_online_cpu so stays
within the bounds of paca[] -- and every CPU is now 'possible'.

Signed-off-by: Matt Evans <matt@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-15 15:02:33 +10:00
Linus Torvalds
eda054770e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: clear bridge resource range if BIOS assigned bad one
  PCI: hotplug/cpqphp, fix NULL dereference
  Revert "PCI: create function symlinks in /sys/bus/pci/slots/N/"
  PCI: change resource collision messages from KERN_ERR to KERN_INFO
2010-06-11 14:15:44 -07:00
Yinghai Lu
837c4ef13c PCI: clear bridge resource range if BIOS assigned bad one
Yannick found that video does not work with 2.6.34.  The cause of this
bug was that the BIOS had assigned the wrong range to the PCI bridge
above the video device.  Before 2.6.34 the kernel would have shrunk
the size of the bridge window, but since
  d65245c PCI: don't shrink bridge resources
the kernel will avoid shrinking BIOS ranges.

So zero out the old range if we fail to claim it at boot time; this will
cause us to allocate a new range at startup, restoring the 2.6.34
behavior.

Fixes regression https://bugzilla.kernel.org/show_bug.cgi?id=16009.

Reported-by: Yannick <yannick.roehlly@free.fr>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-06-11 13:24:51 -07:00
Ananth N Mavinakayanahalli
db97bc7f99 powerpc/kprobes: Remove resume_execution() in kprobes
emulate_step() in kprobe_handler() would've already determined if the
probed instruction can be emulated. We single-step in hardware only if
the instruction couldn't be emulated. resume_execution() therefore is
superfluous -- all we need is to fix up the instruction pointer after
single-stepping.

Thanks to Paul Mackerras for catching this.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-06-02 17:50:37 +10:00
Linus Torvalds
aef4b9aaae Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Don't export cvt_fd & _df when CONFIG_PPC_FPU is not set
  powerpc/44x: icon: select SM502 and frame buffer console support
  powerpc/85xx: Add P1021MDS board support
  powerpc/85xx: Change MPC8572DS camp dtses for MSI sharing
  powerpc/fsl_msi: add removal path and probe failing path
  powerpc/fsl_msi: enable msi sharing through AMP OSes
  powerpc/fsl_msi: enable msi allocation in all banks
  powerpc/fsl_msi: fix the conflict of virt_msir's chip_data
  powerpc/fsl_msi: Add multiple MSI bank support
  powerpc/kexec: Add support for FSL-BookE
  powerpc/fsl-booke: Move the entry setup code into a seperate file
  powerpc/fsl-booke: fix the case where we are not in the first page
  powerpc/85xx: Enable support for ports 3 and 4 on 8548 CDS
  powerpc/fsl-booke: Add hibernation support for FSL BookE processors
  powerpc/e500mc: Implement machine check handler.
  powerpc/44x: Add basic ICON PPC440SPe board support
  powerpc/44x: Fix UART clocks on 440SPe
  powerpc/44x: Add reset-type to katmai.dts
  powerpc/44x: Adding PCI-E support for PowerPC 460SX based SOC.
2010-06-01 14:13:14 -07:00
Linus Torvalds
1f73897861 Merge branch 'for-35' of git://repo.or.cz/linux-kbuild
* 'for-35' of git://repo.or.cz/linux-kbuild: (81 commits)
  kbuild: Revert part of e8d400a to resolve a conflict
  kbuild: Fix checking of scm-identifier variable
  gconfig: add support to show hidden options that have prompts
  menuconfig: add support to show hidden options which have prompts
  gconfig: remove show_debug option
  gconfig: remove dbg_print_ptype() and dbg_print_stype()
  kconfig: fix zconfdump()
  kconfig: some small fixes
  add random binaries to .gitignore
  kbuild: Include gen_initramfs_list.sh and the file list in the .d file
  kconfig: recalc symbol value before showing search results
  .gitignore: ignore *.lzo files
  headerdep: perlcritic warning
  scripts/Makefile.lib: Align the output of LZO
  kbuild: Generate modules.builtin in make modules_install
  Revert "kbuild: specify absolute paths for cscope"
  kbuild: Do not unnecessarily regenerate modules.builtin
  headers_install: use local file handles
  headers_check: fix perl warnings
  export_report: fix perl warnings
  ...
2010-06-01 08:55:52 -07:00
Benjamin Herrenschmidt
a7fed9f736 powerpc: Don't export cvt_fd & _df when CONFIG_PPC_FPU is not set
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-05-31 11:51:54 +10:00
Benjamin Herrenschmidt
ecca1a34be Merge commit 'kumar/next' into next
Conflicts:
	arch/powerpc/sysdev/fsl_msi.c
2010-05-31 10:01:50 +10:00
FUJITA Tomonori
712d3e22a8 powerpc: remove unnecessary sync_single_range_* in swiotlb_dma_ops
sync_single_range_for_cpu and sync_single_range_for_device hooks in
swiotlb_dma_ops are unnecessary because sync_single_for_cpu and
sync_single_for_device are used there.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Becky Bruce <beckyb@kernel.crashing.org>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27 09:12:52 -07:00
Sebastian Andrzej Siewior
b3df895aeb powerpc/kexec: Add support for FSL-BookE
This adds support kexec on FSL-BookE where the MMU can not be simply
switched off. The code borrows the initial MMU-setup code to create the
identical mapping mapping. The only difference to the original boot code
is the size of the mapping(s) and the executeable address.
The kexec code maps the first 2 GiB of memory in 256 MiB steps. This
should work also on e500v1 boxes.
SMP support is still not available.

(Kumar: Added minor change to build to ifdef CONFIG_PPC_STD_MMU_64 some
code that was PPC64 specific)

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-05-24 21:25:32 -05:00
Sebastian Andrzej Siewior
7c08ce718f powerpc/fsl-booke: Move the entry setup code into a seperate file
This patch only moves the initial entry code which setups the mapping
from what ever to KERNELBASE into a seperate file. No code change has
been made here.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-05-24 14:01:12 -05:00
Sebastian Andrzej Siewior
2289d2d1a8 powerpc/fsl-booke: fix the case where we are not in the first page
During boot we change the mapping a few times until we have a "defined"
mapping. During this procedure a small 4KiB mapping is created and after
that one a 64MiB. Currently the offset of the 4KiB page in that we run
is zero because the complete startup up code is in first page which
starts at RPN zero.
If the code is recycled and moved to another location then its execution
will fail because the start address in 64 MiB mapping is computed
wrongly. It does not consider the offset to the page from the begin of
the memory.
This patch fixes this. Usually (system boot) r25 is zero so this does
not change anything unless the code is recycled.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2010-05-24 14:00:53 -05:00