sh/highmem: Remove all traces of unused cruft

For whatever reasons SH has highmem bits all over the place but does
not enable it via Kconfig. Remove the bitrot.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20201103095856.979798613@linutronix.de
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Morton <akpm@linux-foundation.org>

sh: remove sh5 support

sh5 never became a product and has probably never really worked.

Remove it by recursively deleting all associated Kconfig options
and all corresponding files.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rich Felker <dalias@libc.org>

sh: include: convert to SPDX identifiers

Update license to use SPDX-License-Identifier instead of verbose license
text.

Link: http://lkml.kernel.org/r/87ftvccszx.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh: use generic fixmap.h

Signed-off-by: Mark Salter <msalter@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Revert "sh: Ensure fixmap and store queue space can co-exist."

This reverts commit 20e7c297efeca0861adcca073a0d283da659834b.
With store queues enabled the area above P4SEG has special properties
from the MMU's point of view, which was causing fixmap failure. We'll
have to do something else to satisfy the vmalloc range check.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh64: Kill off unused fixed I/O mapping window.

This was reworked some time ago to go through fixmaps instead, leaving
the range itself unused. As such, kill off the remaining references and
hand over the remaining space for fixmaps directly. This also makes it
possible to simplify the vmalloc fault case as we no longer have to care
about the special section.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Ensure fixmap and store queue space can co-exist.

At the moment the top of the fixmap space is calculated from P4SEG, which
places it at the end of the store queue space when that API is enabled.
Make sure we use P3_ADDR_MAX here instead to find the proper address
limit. With this done, it's also possible to switch to the generic
vmalloc address range check now that VMALLOC_START/END encapsulate the
translatable areas that we care about.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: fix up an off-by-1 in the number of early ioremap fixmaps.

There was an off-by-1 in the begin/end of the ioremap fixmaps, leaving us
with a spurious entry. In practice this wasn't a problem since we aligned
on a PMD boundary anyways, but this makes it consistent with the
intention and the other fixmaps.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Conserve fixmap slots when IOREMAP_FIXED=n.

Presently the IOREMAP_FIXED fixmaps are always defined, even if the
platform isn't capable of supporting it. Since we already have an ifdef
for it, ifdef the entries, too.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Kill off the special uncached section and fixmap.

Now that cached_to_uncached works as advertized in 32-bit mode and we're
never going to be able to map < 16MB anyways, there's no need for the
special uncached section. Kill it off.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Add fixed ioremap support

Some devices need to be ioremap'd and accessed very early in the boot
process. It is not possible to use the standard ioremap() function in
this case because that requires kmalloc()'ing some virtual address space
and kmalloc() may not be available so early in boot.

This patch provides fixmap mappings that allow physical address ranges
to be remapped into the kernel address space during the early boot
stages.

Signed-off-by: Matt Fleming <matt@console-pimps.org>

sh: Generalise the pte handling code for the fixmap path

Generalise the code for setting and clearing pte's and allow TLB entries
to be pinned and unpinned if the _PAGE_WIRED flag is present.

Signed-off-by: Matt Fleming <matt@console-pimps.org>

sh: Improve performance of SH4 versions of copy/clear_user_highpage

The previous implementation of clear_user_highpage and copy_user_highpage
checked to see if there was a D-cache aliasing issue between the user
and kernel mappings of a page, but if there was they always did a
flush with writeback on the dirtied kernel alias.

However as we now have the ability to map a page into kernel space
with the same cache colour as the user mapping, there is no need to
write back this data.

Currently we also invalidate the kernel alias as a precaution, however
I'm not sure if this is actually required.

Also correct the definition of FIX_CMAP_END so that the mappings created
by kmap_coherent() are actually at the correct colour.

Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Factor in cpu id for selection of cache colour fixmap.

In the SMP VIPT case the page copy/clear ops still perform colouring,
care needs to be taken that CPUs don't end up stepping on each other,
so we give them a bit of room to work with.

At the same time, we reduce the worst-case colouring given that these
pages are always consumed.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: migrate to arch/sh/include/

This follows the sparc changes a439fe51a1f8eb087c22dd24d69cebae4a3addac.

Most of the moving about was done with Sam's directions at:

http://marc.info/?l=linux-sh&m=121724823706062&w=2

with subsequent hacking and fixups entirely my fault.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>