Split asm/tlbflush.h into:
asm/nohash/tlbflush.h
asm/book3s/32/tlbflush.h
asm/book3s/64/tlbflush.h (already existing)
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

asm/tlbflush.h is only needed for:
- using functions xxx_flush_tlb_xxx()
- using MMU_NO_CONTEXT
- including asm-generic/pgtable.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

mmu-44x.h doesn't need asm/page.h if PAGE_SHIFT are replaced by CONFIG_PPC_XX_PAGES
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove superflous includes and add missing ones
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

PPC_PIN_SIZE is specific to the 44x and is defined in mmu.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

set_breakpoint() is only used in process.c so make it static
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Files not using fixmap consts or functions don't need asm/fixmap.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

files not using feature fixup don't need asm/feature-fixups.h
files using feature fixup need asm/feature-fixups.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Only include linux/stringify.h is files using __stringify()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch moves ASM_CONST() and stringify_in_c() into
dedicated asm-const.h, then cleans all related inclusions.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: asm-compat.h should include asm-const.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Files not using cpu_has_feature() don't need cpu_has_feature.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

page.h doesn't need kdump.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This delay was in the very first OPAL console commit 6.5 years ago,
and came from the vio hvc driver. The firmware console has hardened
sufficiently to remove it.
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The RAW console does not need writes to be atomic, so relax
opal_put_chars to be able to do partial writes, and implement an
_atomic variant which does not take a spinlock. This API is used
in xmon, so the less locking that is used, the better chance there
is that a crash can be debugged.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

OPAL console writes do not have to synchronously flush firmware /
hardware buffers unless they are going through the udbg path.

Remove the unconditional flushing from opal_put_chars. Flush if
there was no space in the buffer as an optimisation (callers loop
waiting for success in that case). udbg flushing is moved to
udbg_opal_putc.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

opal_put_chars deals with partial writes because in OPALv1,
opal_console_write_buffer_space did not work correctly. That firmware
is not supported.

This reworks the opal_put_chars code to no longer deal with partial
writes by turning them into full writes. Partial write handling is still
supported in terms of what gets returned to the caller, but it may not
go to the console atomically. A warning message is printed in this
case.

This allows console flushing to be moved out of the opal_write_lock
spinlock. That could cause the lock to be held for long periods if the
console is busy (especially if it was being spammed by firmware),
which is dangerous because the lock is taken by xmon to debug the
system. Flushing outside the lock improves the situation a bit.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

A new console flushing firmware API was introduced to replace event
polling loops, and implemented in opal-kmsg with affddff6
("powerpc/powernv: Add a kmsg_dumper that flushes console output on
panic"), to flush the console in the panic path.

The OPAL console driver has other situations where interrupts are off
and it needs to flush the console synchronously. These still use a
polling loop.

So move the opal-kmsg flush code to opal_flush_console, and use the
new function in opal-kmsg and opal_put_chars.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Use the more refined and tested event polling loop from opal_put_chars
as the fallback console flush in the opal-kmsg path. This loop is used
by the console driver today, whereas the opal-kmsg fallback is not
likely to have been used for years.

Use WARN_ONCE rather than a printk when the fallback is invoked to
prepare for moving the console flush into a common function.
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

OPAL_CONSOLE_FLUSH is documented as being able to return OPAL_BUSY,
so implement the standard OPAL_BUSY handling for it.
Reviewed-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The OPAL console driver does not delay in case it gets OPAL_BUSY or
OPAL_BUSY_EVENT from firmware.

It can't yet be made to sleep because it is called under spinlock,
but it can be changed to the standard OPAL_BUSY loop form, and a
delay added to keep it from hitting the firmware too frequently.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The intention here is to consume and discard the remaining buffer
upon error. This works if there has not been a previous partial write.
If there has been, then total_len is no longer total number of bytes
to copy. total_len is always "bytes left to copy", so it should be
added to written bytes.

This code may not be exercised any more if partial writes will not be
hit, but this is a small bugfix before a larger change.
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Fixes: 8034f715 ("powernv/opal-dump: Convert to irq domain")

Converts all the return explicit number to a more proper IRQ_HANDLED,
which looks proper incase of interrupt handler returning case.

Here, It also removes error message like "nobody cared" which was
getting unveiled while returning -1 or 0 from handler.
Signed-off-by: Mukesh Ojha <mukesh02@linux.vnet.ibm.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Moves the return value check of 'opal_dump_info' to a proper place which
was previously unnecessarily filling all the dump info even on failure.
Signed-off-by: Mukesh Ojha <mukesh02@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Acked-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Since commit dc310669 ("powerpc: tm: Always use fp_state and
vr_state to store live registers") tm_reclaim_thread() doesn't use the
parameter anymore, both callers have to bother getting it as they have
no need for a struct thread_info either.

Just remove it and adjust the callers.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In commit eb5c3f1c ("powerpc: Always save/restore checkpointed regs
during treclaim/trecheckpoint") __tm_recheckpoint was modified to no
longer take the second parameter 'unsigned long orig_msr' as part of a
TM rewrite to simplify the reclaiming/recheckpointing process.

There is a comment in the asm file where the function is delcared which
has an incorrect prototype with the 'orig_msr' parameter.

This patch corrects the comment.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch reworked selftest memcmp_64 so that memcmp selftest can
cover more test cases.

It adds testcases for:
- memcmp over 4K bytes size.
- s1/s2 with different/random offset on 16 bytes boundary.
- enter/exit_vmx_ops pairness.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
[mpe: Add -maltivec to fix build on some toolchains]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch is based on the previous VMX patch on memcmp().

To optimize ppc64 memcmp() with VMX instruction, we need to think about
the VMX penalty brought with: If kernel uses VMX instruction, it needs
to save/restore current thread's VMX registers. There are 32 x 128 bits
VMX registers in PPC, which means 32 x 16 = 512 bytes for load and store.

The major concern regarding the memcmp() performance in kernel is KSM,
who will use memcmp() frequently to merge identical pages. So it will
make sense to take some measures/enhancement on KSM to see whether any
improvement can be done here.  Cyril Bur indicates that the memcmp() for
KSM has a higher possibility to fail (unmatch) early in previous bytes
in following mail.
	https://patchwork.ozlabs.org/patch/817322/#1773629
And I am taking a follow-up on this with this patch.

Per some testing, it shows KSM memcmp() will fail early at previous 32
bytes.  More specifically:
    - 76% cases will fail/unmatch before 16 bytes;
    - 83% cases will fail/unmatch before 32 bytes;
    - 84% cases will fail/unmatch before 64 bytes;
So 32 bytes looks a better choice than other bytes for pre-checking.

The early failure is also true for memcmp() for non-KSM case. With a
non-typical call load, it shows ~73% cases fail before first 32 bytes.

This patch adds a 32 bytes pre-checking firstly before jumping into VMX
operations, to avoid the unnecessary VMX penalty. It is not limited to
KSM case. And the testing shows ~20% improvement on memcmp() average
execution time with this patch.

And note the 32B pre-checking is only performed when the compare size
is long enough (>=4K currently) to allow VMX operation.

The detail data and analysis is at:
https://github.com/justdoitqd/publicFiles/blob/master/memcmp/README.mdSigned-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch add VMX primitives to do memcmp() in case the compare size
is equal or greater than 4K bytes. KSM feature can benefit from this.

Test result with following test program(replace the "^>" with ""):
------
># cat tools/testing/selftests/powerpc/stringloops/memcmp.c
>#include <malloc.h>
>#include <stdlib.h>
>#include <string.h>
>#include <time.h>
>#include "utils.h"
>#define SIZE (1024 * 1024 * 900)
>#define ITERATIONS 40

int test_memcmp(const void *s1, const void *s2, size_t n);

static int testcase(void)
{
        char *s1;
        char *s2;
        unsigned long i;

        s1 = memalign(128, SIZE);
        if (!s1) {
                perror("memalign");
                exit(1);
        }

        s2 = memalign(128, SIZE);
        if (!s2) {
                perror("memalign");
                exit(1);
        }

        for (i = 0; i < SIZE; i++)  {
                s1[i] = i & 0xff;
                s2[i] = i & 0xff;
        }
        for (i = 0; i < ITERATIONS; i++) {
		int ret = test_memcmp(s1, s2, SIZE);

		if (ret) {
			printf("return %d at[%ld]! should have returned zero\n", ret, i);
			abort();
		}
	}

        return 0;
}

int main(void)
{
        return test_harness(testcase, "memcmp");
}
------
Without this patch (but with the first patch "powerpc/64: Align bytes
before fall back to .Lshort in powerpc64 memcmp()." in the series):
	4.726728762 seconds time elapsed                                          ( +-  3.54%)
With VMX patch:
	4.234335473 seconds time elapsed                                          ( +-  2.63%)
		There is ~+10% improvement.

Testing with unaligned and different offset version (make s1 and s2 shift
random offset within 16 bytes) can archieve higher improvement than 10%..
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Some old tool chains don't know about instructions like vcmpequd.

This patch adds .long macro for vcmpequd and vcmpequb, which is
a preparation to optimize ppc64 memcmp with VMX instructions.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Currently memcmp() 64bytes version in powerpc will fall back to .Lshort
(compare per byte mode) if either src or dst address is not 8 bytes aligned.
It can be opmitized in 2 situations:

1) if both addresses are with the same offset with 8 bytes boundary:
memcmp() can compare the unaligned bytes within 8 bytes boundary firstly
and then compare the rest 8-bytes-aligned content with .Llong mode.

2)  If src/dst addrs are not with the same offset of 8 bytes boundary:
memcmp() can align src addr with 8 bytes, increment dst addr accordingly,
 then load src with aligned mode and load dst with unaligned mode.

This patch optmizes memcmp() behavior in the above 2 situations.

Tested with both little/big endian. Performance result below is based on
little endian.

Following is the test result with src/dst having the same offset case:
(a similar result was observed when src/dst having different offset):
(1) 256 bytes
Test with the existing tools/testing/selftests/powerpc/stringloops/memcmp:
- without patch
	29.773018302 seconds time elapsed                                          ( +- 0.09% )
- with patch
	16.485568173 seconds time elapsed                                          ( +-  0.02% )
		-> There is ~+80% percent improvement

(2) 32 bytes
To observe performance impact on < 32 bytes, modify
tools/testing/selftests/powerpc/stringloops/memcmp.c with following:
-------
 #include <string.h>
 #include "utils.h"

-#define SIZE 256
+#define SIZE 32
 #define ITERATIONS 10000

 int test_memcmp(const void *s1, const void *s2, size_t n);
--------

- Without patch
	0.244746482 seconds time elapsed                                          ( +-  0.36%)
- with patch
	0.215069477 seconds time elapsed                                          ( +-  0.51%)
		-> There is ～+13% improvement

(3) 0~8 bytes
To observe <8 bytes performance impact, modify
tools/testing/selftests/powerpc/stringloops/memcmp.c with following:
-------
 #include <string.h>
 #include "utils.h"

-#define SIZE 256
-#define ITERATIONS 10000
+#define SIZE 8
+#define ITERATIONS 1000000

 int test_memcmp(const void *s1, const void *s2, size_t n);
-------
- Without patch
       1.845642503 seconds time elapsed                                          ( +- 0.12% )
- With patch
       1.849767135 seconds time elapsed                                          ( +- 0.26% )
		-> They are nearly the same. (-0.2%)
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This patch adds error reporting to H_ENTER and H_READ hcalls. A
failure for both these hcalls are mostly fatal and it would be good to
log the failure reason.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Switch from printk to pr_fmt() / pr_xxx().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We do this in some part. This patch make sure we always try to search
for hpte without holding lock and redo the compare with lock held once
match found.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

No functional change
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

When computing the starting slot number for a hash page table group we used
to do this
hpte_group = ((hash & htab_hash_mask) * HPTES_PER_GROUP) & ~0x7UL;

Multiplying with 8 (HPTES_PER_GROUP) imply the last three bits are 0. Hence we
really don't need to clear then separately.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We do this only with VMEMMAP config so that our page_to_[nid/section] etc are not
impacted.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

With SPARSEMEM config enabled, we make sure that we don't add sections beyond
MAX_PHYSMEM_BITS range. This results in not building vmemmap mapping for
range beyond max range. But our memblock layer looks the device tree and create
mapping for the full memory range. Prevent this by checking against
MAX_PHSYSMEM_BITS when doing memblock_add.

We don't do similar check for memeblock_reserve_range. If reserve range is beyond
MAX_PHYSMEM_BITS we expect that to be configured with 'nomap'. Any other
reserved range should come from existing memblock ranges which we already
filtered while adding.

This avoids crash as below when running on a system with system ram config above
MAX_PHSYSMEM_BITS

 Unable to handle kernel paging request for data at address 0xc00a001000000440
 Faulting instruction address: 0xc000000001034118
 cpu 0x0: Vector: 300 (Data Access) at [c00000000124fb30]
     pc: c000000001034118: __free_pages_bootmem+0xc0/0x1c0
     lr: c00000000103b258: free_all_bootmem+0x19c/0x22c
     sp: c00000000124fdb0
    msr: 9000000002001033
    dar: c00a001000000440
  dsisr: 40000000
   current = 0xc00000000120dd00
   paca    = 0xc000000001f60000^I irqmask: 0x03^I irq_happened: 0x01
     pid   = 0, comm = swapper
 [c00000000124fe20] c00000000103b258 free_all_bootmem+0x19c/0x22c
 [c00000000124fee0] c000000001010a68 mem_init+0x3c/0x5c
 [c00000000124ff00] c00000000100401c start_kernel+0x298/0x5e4
 [c00000000124ff90] c00000000000b57c start_here_common+0x1c/0x520
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Similarly as we just did for 32-bit, add phony targets for generating
a little endian and Book3E allmodconfig. These aren't covered by the
regular allmodconfig, which is big endian and Book3S due to the way
the Kconfig symbols are structured.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>