to allow future git mv of the driver into drivers/clocksource

Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

The original distinction was done as they were developed at different
times and primarily because they are specific to UP (RTC) and SMP (GFRC).

But given that driver handles that at runtime, (i.e. not allowing
RTC as clocksource in SMP), we can simplify things a bit.

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

The motivation is to identify ARC750 vs. ARC770 (we currently print
generic "ARC700").

A given ARC700 release could be 750 or 770, with same ARCNUM (or family
identifier which is unfortunate). The existing arc_cpu_tbl[] kept a single
concatenated string for core name and release which thus doesn't work
for 750 vs. 770 identification.

So split this into 2 tables, one with core names and other with release.
And while we are at it, get rid of the range checking for family numbers.
We just document the known to exist cores running Linux and ditch
others.

With this in place, we add detection of ARC750 which is
 - cores 0x33 and before
 - cores 0x34 and later with MMUv2

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

This came to light when helping a customer with oldish ARC750 core who
were getting instruction errors because of lack of SWAPE but boot log
was incorrectly printing it as being present

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

On older arc700 cores, some of the features configured were not present
in Build config registers. To print about them at boot, we just use the
Kconfig option i.e. whether linux is built to use them or not.
So yes this seems bogus, but what else can be done. Moreover if linux is
booting with these enabled, then the Kconfig info is a good indicator
anyways.

Over time these "hacks" accumulated in read_arc_build_cfg_regs() as well
as arc_cpu_mumbojumbo(). so refactor and move all of those in a single
place: read_arc_build_cfg_regs(). This causes some code redcution too:

| bloat-o-meter2 arch/arc/kernel/setup.o.0 arch/arc/kernel/setup.o.1
| add/remove: 0/0 grow/shrink: 2/1 up/down: 64/-132 (-68)
| function                                     old     new   delta
| setup_processor                              610     670     +60
| cpuinfo_arc700                                76      80      +4
| arc_cpu_mumbojumbo                           752     620    -132

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

Previously we would not print the case when IOC existed but was not
enabled.

And while at it, reduce one line off boot printing by consolidating
the Peripheral address space and IO-Coherency which in a way
applies to them

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

num_possible_cpus() returns how many CPUs may be present on system.
However we want the highest possible CPU number.
This may be differ in a sparsed possible CPUs map.
Such map achived by OF for plat-eznps.

For example if we have:
possible cpus mask 0,3

Then:
num_possible_cpus() is equal 2
	while
nr_cpu_ids is equal 4.

Only for value 4 c_start() will provide correct cpuinfo at procfs.

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

HS release 3.0 provides for even more flexibility in specifying the
volatile address space for mapping peripherals.

With HS 2.1 @start was made flexible / programmable - with HS 3.0 even
@end can be setup (vs. fixed to 0xFFFF_FFFF before).

So add code to reflect that and while at it remove an unused struct
defintion

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

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

The syscall ABI includes the gcc functional calling ABI since a syscall
implies userland caller and kernel callee.

The current gcc ABI (v3) for ARCv2 ISA required 64-bit data be passed in
even-odd register pairs, (potentially punching reg holes when passing such
values as args). This was partly driven by the fact that the double-word
LDD/STD instructions in ARCv2 expect the register alignment and thus gcc
forcing this avoids extra MOV at the cost of a few unused register (which we
have plenty anyways).

This however was rejected as part of upstreaming gcc port to HS. So the new
ABI v4 doesn't enforce the even-odd reg restriction.

Do note that for ARCompact ISA builds v3 and v4 are practically the same in
terms of gcc code generation.

In terms of change management, we infer the new ABI if gcc 6.x onwards
is used for building the kernel.

This also needs a stable backport to enable older kernels to work with
new tools/user-space

Cc: <stable@vger.kernel.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>