Pull parisc updates from Helge Deller:
 "One real bugfix to change the io_pgetevents_time64() syscall to use
  the compat implementation when running in compat mode, otherwise the
  signed int32 parameters min_nr and nr will be incorrectly handled as
  unsigned int64 values.

  Other than that just small cleanups:

   - hardware database housekeeping and proper /proc/iomem output

   - add proper function exit code if probe functions fail

   - drop stale variables (pa_swapper_pg_lock)

   - drop unneccessary zero-initializations

   - typo fixes in comments"

* tag 'for-5.20/parisc-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  Input: gscps2 - check return value of ioremap() in gscps2_probe()
  parisc: io_pgetevents_time64() needs compat syscall in 32-bit compat mode
  parisc: Drop zero variable initialisations in mm/init.c
  parisc: Do not initialise statics to 0
  parisc: Check the return value of ioremap() in lba_driver_probe()
  parisc: Drop pa_swapper_pg_lock spinlock
  parisc: Fix comment typo in fault.c
  parisc: Fix device names in /proc/iomem
  parisc: Clean up names in hardware database

This spinlock was dropped with commit b7795074a046 ("parisc: Optimize
per-pagetable spinlocks") in kernel v5.12.

Remove it to silence a sparse warning.

Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: kernel test robot <lkp@intel.com>
Cc: <stable@vger.kernel.org> # v5.12+

__kunmap_ {local,atomic}() currently take pointers to void. However, this
is semantically incorrect, since these functions do not change the memory
their arguments point to.

Therefore, make this semantics explicit by modifying the
__kunmap_{local,atomic}() prototypes to take pointers to const void.

As a side effect, compilers may produce more efficient code.

Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Helge Deller <deller@gmx.de>  # parisc
Suggested-by: David Sterba <dsterba@suse.cz>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Anonymous pages are allocated with the shared mappings colouring,
SHM_COLOUR. Since the alias boundary on machines with PA8800 and
PA8900 processors is unknown, flush_user_cache_page() might not
flush all mappings of a shared anonymous page. Flushing the whole
data cache flushes all mappings.

This won't fix all coherency issues with shared mappings but it
seems to work well in practice.  I haven't seen any random memory
faults in almost a month on a rp3440 running as a debian buildd
machine.

There is a small preformance hit.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org   # v5.18+

The only place we need to ensure all outstanding cache coherence
operations are complete is in invalidate_kernel_vmap_range. All
parisc drivers synchronize DMA operations internally and do not
call invalidate_kernel_vmap_range. We only need this for non-coherent
I/O operations.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

Originally, I was convinced that we needed to use tmpalias flushes
everwhere, for both user and kernel flushes. However, when I modified
flush_kernel_dcache_page_addr, to use a tmpalias flush, my c8000
would crash quite early when booting.

The PDC returns alias values of 0 for the icache and dcache. This
indicates that either the alias boundary is greater than 16MB or
equivalent aliasing doesn't work. I modified the tmpalias code to
make it easy to try alternate boundaries. I tried boundaries up to
128MB but still kernel tmpalias flushes didn't work on c8000.

This led me to conclude that tmpalias flushes don't work on PA8800
and PA8900 machines, and that we needed to flush directly using the
virtual address of user and kernel pages. This is likely the major
cause of instability on the c8000 and rp34xx machines.

Flushing user pages requires doing a temporary context switch as we
have to flush pages that don't belong to the current context. Further,
we have to deal with pages that aren't present. If a page isn't
present, the flush instructions fault on every line.

Other code has been rearranged and simplified based on testing. For
example, I introduced a flush_cache_dup_mm routine. flush_cache_mm
and flush_cache_dup_mm differ in that flush_cache_mm calls
purge_cache_pages and flush_cache_dup_mm calls flush_cache_pages.
In some implementations, pdc is more efficient than fdc. Based on
my testing, I don't believe there's any performance benefit on the
c8000.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

This reverts commit a58e9d0984e8dad53f17ec73ae3c1cc7f8d88151.

Triggers segfaults with 32-bit kernels on PA8500 machines.

Signed-off-by: Helge Deller <deller@gmx.de>

If CONFIG_HOTPLUG_CPU is enabled, those functions will be run again
after bootup. So they need to reside in the .text section.

Signed-off-by: Helge Deller <deller@gmx.de>

This reverts commit 53d862fac4a09b9c56cca0433fa9de5732fd05a1.

It turned out that flush_kernel_vmap_range() is being called with
interrupts disabled.  There's no way to flush entire cache with
interrupts disabled.

Signed-off-by: Helge Deller <deller@gmx.de>

Cache move-in for virtual accesses is controlled by the TLB.  Thus,
we must generally purge TLB entries before flushing.  The flush routines
must use TLB entries that inhibit cache move-in.

V2: Load physical address prior to flushing TLB.  In flush_cache_page,
flush TLB when flushing and purging.

V3: Don't flush when start equals end.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>