Fix typos, most reported by "codespell arch/arc".  Only touches comments,
no code changes.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/r/202311280906.VAIwEAfT-lkp@intel.com/
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308221549.XKufWEWp-lkp@intel.com/
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

 - boot log now clearly per ISA
 - global struct cpuinfo_arc[] elimiated
 - local struct struct arcinfo kept for passing info
   between functions

Tested-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308162101.Ve5jBg80-lkp@intel.com
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

Signed-off-by: Vineet Gupta <vgupta@kernel.org>

This is first step in eliminating struct cpuinfo_arc[NR_CPUS]

Back when we had just ARCompact ISA, the idea was to read/bit-fiddle
the BCRs once and and cache decoded information in a global struct ready
to use.

With ARCv2 it was modified to contained abstract / ISA agnostic
information.

However with ARCv3 there 's too much disparity to abstract in common
structures. So drop the entire decode once and store paradigm. Afterall
there's only 2 users of this machinery anyways:  boot printing and
cat /proc/cpuinfo. None is performance critical to warrant locking away
resident memory per cpu.

This patch is first step in that direction
 - decouples struct cpuinfo_arc_mmu from global struct cpuinfo_arc
 - mmu code still has a trimmed down static version of
   struct cpuinfo_arc_mmu to cache information needed in performance
   critical code such as tlb flush routines
 - folds read_decode_mmu_bcr() into arc_mmu_mumbojumbo()
 - setup_processor() directly calls arc_mmu_init() and not via
   arc_cpu_init()

Tested-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308151213.qKZPMiyz-lkp@intel.com/
Signed-off-by: Vineet Gupta <vgupta@kernel.org>

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

As of today the ICCM and DCCM size checks are incorrectly using
mismatched units (KiB checked against bytes). The CONFIG_ARC_DCCM_SZ
and CONFIG_ARC_ICCM_SZ are in KiB, but the size calculated in
runtime and stored in cpu->dccm.sz and cpu->iccm.sz is in bytes.

Fix that.

Reported-by: Paul Greco <pmgreco@us.ibm.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

To be able to run DSP-enabled userspace applications with AGU
(address generation unit) extensions we additionally need to
save and restore following registers at context switch:
 * AGU_AP*
 * AGU_OS*
 * AGU_MOD*

Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

When DSP extensions are present, some of the regular integer instructions
such as DIV, MACD etc are executed in the DSP unit with semantics alterable
by flags in DSP_CTRL aux register. This register is writable by userspace
and thus can potentially affect corresponding instructions in kernel code,
intentionally or otherwise. So safegaurd kernel by effectively disabling
DSP_CTRL upon bootup and every entry to kernel.

Do note that for this config we simply zero out the DSP_CTRL reg assuming
userspace doesn't really care about DSP. The next patch caters to the DSP
aware userspace where this reg is saved/restored upon kernel entry/exit.

Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>