-platform API is retired and instead callbacks are used
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: NArnd Bergmann <arnd@arndb.de>

The orig platform code orgnaization was singleton design pattern - only
one platform (and board thereof) would build at a time.

Thus any platform/board specific code (e.g. irq init, early init ...)
expected by ARC common code was exported as well defined set of APIs,
with only ONE instance building ever.

Now with multiple-platform build requirement, that design of code no
longer holds - multiple board specific calls need to build at the same
time - so ARC common code can't use the API approach, it needs a
callback based design where each board registers it's specific set of
functions, and at runtime, depending on board detection, the callbacks
are used from the registry.

This commit adds all the infrastructure, where board specific callbacks
are specified as a "maThine description".

All the hooks are placed in right spots, no board callbacks registered
yet (with MACHINE_STARt/END constructs) so the hooks will not run.

Next commit will actually convert the platform to this infrastructure.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: NArnd Bergmann <arnd@arndb.de>

This is more natural and is now doable since the choice constructs are
gone.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

This mini patchseries addresses the lack of multi-platform-image support
in ARC port.

Older build system only supported one platform(soc) to build at a time
and further only one board of that platform could be built. There was no
technical reason for that - we just didn't have the need.

So the first step towards multi-platform (and multi-board) builds it to
allow build system to do that.

So as applicable, <choice .. endchoice> => <menu .. endmenu>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: NArnd Bergmann <arnd@arndb.de>

Implement ioremap_prot() to allow mapping IO memory with variable
protection
via TLB.

Implementing this allows the /dev/mem driver to use its generic access()
VMA callback, which in turn allows ptrace to examine data in memory
mapped regions mapped via /dev/mem, such as Arc DCCM.

The end result is that it is possible to examine values of variables
placed into DCCM in user space programs via GDB.

CC: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
CC: Noam Camus <noamc@ezchip.com>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Signed-off-by: NGilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

1. ./genfilelist.pl arch/arc/include/asm/

2. Create arch/arc/include/uapi/asm/Kbuild as follows

	+# UAPI Header export list
	+include include/uapi/asm-generic/Kbuild.asm

3. ./disintegrate-one.pl arch/arc/include/{,uapi/}asm/<above-list>

4. Edit arch/arc/include/asm/Kbuild to remove ref to
	asm-generic/Kbuild.asm

- To work around empty uapi/asm/setup.h added a placholder comment.
- Also a manual #ifdef __ASSEMBLY__ for a late ptrace change
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: David Howells <dhowells@redhat.com>

This allows ARC Target to do I/O to host in absence of any peripherals
whatsoever, assisted by Metaware Hostlink facility.

Further we have a FUSE based filesystem which makes us mount/access host
filesystem on target and do fops.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

* Includes mapping of CCMs in address space
* Annotations to move arbitrary code/data into CCM
* Moving some of the critical code/data into CCM
* Runtime detection/reporting
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

Although with uClibc there's more we need to do
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>

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

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

Signed-off-by: NMischa Jonker <mjonker@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Acked-by: NJason Wessel <jason.wessel@windriver.com>

ARC700 doesn't natively support unaligned access, but can be emulated
-Unaligned Access Exception
-Disassembly at the Fault address to find the exact insn (long/short)

Also per Arnd's comment, we runtime control it using 2 sysctl knobs:
* SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble
* SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt

Originally contributed by Tim Yao <tim.yao@amlogic.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Tim Yao <tim.yao@amlogic.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

PARISC defines /proc/sys/kernel/unaligned-trap to runtime toggle
unaligned access emulation.

The exact mechanics of enablig/disabling are still arch specific, we can
make the sysctl usable by other arches.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NHelge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Serge Hallyn <serge.hallyn@canonical.com>

Origin port done by Rajeshwar Ranga
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>

In-kernel disassembler

Due Credits
* Orig written by Rajeshwar Ranga
* Consolidation/cleanups by Mischa Jonker
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
Cc: Mischa Jonker <mjonker@synopsys.com>

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

-Originally written by Rajeshwar Ranga
-Derived off of generic unwinder in 2.6.19 and adapted to ARC
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>

ARC common code to enable a SMP system + ISS provided SMP extensions.

ARC700 natively lacks SMP support, hence some of the core features are
are only enabled if SoCs have the necessary h/w pixie-dust. This
includes:
-Inter Processor Interrupts (IPI)
-Cache coherency
-load-locked/store-conditional
...

The low level exception handling would be completely broken in SMP
because we don't have hardware assisted stack switching. Thus a fair bit
of this code is repurposing the MMU_SCRATCH reg for event handler
prologues to keep them re-entrant.

Many thanks to Rajeshwar Ranga for his initial "major" contributions to
SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help
with resurrecting that in 3.2 kernel (2012).

Note that this platform code is again singleton design pattern - so
multiple SMP platforms won't build at the moment - this deficiency is
addressed in subsequent patches within this series.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>

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

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

There is a bit of hack/kludge right now where we disable preemption if a
L2 (High prio) IRQ is taken while L1 (Low prio) is active.

Need to revisit this
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Robert Richter <rric@kernel.org>
Cc: oprofile-list@lists.sf.net
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>

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

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

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

With this we get to a running kernel on ISS

---------------------------------->8-----------------------------------
Linux version 3.8.0-rc3+ (vineetg@vineetg-Latitude) (gcc version 4.4.7
(ARCompact elf32 toolchain (built 20121213)) ) #3 Thu Jan 17 14:22:05
IST 2013
Board "arc-angel4" from snps (Manufacturer)
Memory size set via devicetree 256M
[plat-arcfpga]: registering early dev resources
bootconsole [early_ARCuart0] enabled
pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768
pcpu-alloc: [0] 0
Built 1 zonelists in Zone order, mobility grouping on.  Total pages:
32624
Kernel command line: console=ttyARC0,115200n8
PID hash table entries: 1024 (order: -1, 4096 bytes)
Dentry cache hash table entries: 32768 (order: 4, 131072 bytes)
Inode-cache hash table entries: 16384 (order: 3, 65536 bytes)
Memory Available: 248M / 256M (1312K code, 463K data, 4184K init, 1400K
reserv)
SLUB: Genslabs=12, HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
NR_IRQS:16
Console: colour dummy device 80x25
Calibrating delay loop... 39.73 BogoMIPS (lpj=198656)
pid_max: default: 32768 minimum: 301
Mount-cache hash table entries: 1024
devtmpfs: initialized
[plat-arcfpga]: registering device resources
bio: create slab <bio-0> at 0
Switching to clocksource ARC RTSC
io scheduler noop registered (default)
arc-uart: ttyARC0 at MMIO 0xc0fc1000 (irq = 5) is a arc-uart
console [ttyARC0] enabled, bootconsole disabled
console [ttyARC0] enabled, bootconsole disabled
mousedev: PS/2 mouse device common for all mice
Warning: unable to open an initial console.
Freeing unused kernel memory: 4184k [80002000] to [80418000]
Mounting proc
Mounting sysfs
Mounting devpts
Setting hostname to ARCLinux
Starting System logger (syslogd)
Bringing up loopback device
ifconfig: socket: Function not implemented
route: socket: Function not implemented
Disk not detected !
Mounting tmpfs
mount: mounting tmpfs on /dev/shm failed: Invalid argument
/etc/init.d/rcS: line 76: can't create /proc/sys/kernel/msgmni:
nonexistent directory

Please press Enter to activate this console.
***********************************************************************
                        Welcome to ARCLinux
***********************************************************************
[ARCLinux]$

---------------------------------->8-----------------------------------
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

This was part of port buildup strategy from Arnd to have a minimal kernel
at first and then add optional features (stacktracing, ptrace, smp,
kprobes, oprofile....)
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

* arc-uart platform device now populated dynamically, using
  of_platform_populate() - applies to any other device whatsoever.

* uart in turn requires incore arc-intc to be also present in DT

* A irq-domain needs to be instantiated for IRQ requests by DT probed
  device (e.g. arc-uart)

TODO: switch over to linear irq domain once all devs have been
      transitioned to DT
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>

* mem size now runtime configured (prev CONFIG_ARC_PLAT_SDRAM_SIZE)
* core cpu clk runtime configured (prev CONFIG_ARC_PLAT_CLK)
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>

This is minimal infrastructure needed for devicetree work.
It uses an a sample "skeleton" devicetree - embedded in kernel image -
to print the board, manufacturer by parsing the top-level "compatible"
string.

As of now we don't need any additional "board" specific "machine_desc".

TODO: support interpreting the command line as boot-loader passed dtb
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: James Hogan <james.hogan@imgtec.com>
Reviewed-by: NRob Herring <rob.herring@calxeda.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>

N.B. This is old style of hardcoding platform device specific info
in code and it's instantiation thererof using platform_add_devices().
Subsequent patches replace this with DeviceTree based runtime probe.

This patch has been retained just as an example of "don't-do-this" for
newer kernel ports.
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>

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

This includes recent changes to make handler "retry" and/or "killable"

The killable (early exit) logic is loosely based on how SH implements it
	return if SIGKILL + either of VM_FAULT_OOM or VM_FAULT_RETRY
which is different from Hexagon implementation which would NOT early
exit for
	SIGKILL + VM_FAULT_OOM + !VM_FAULT_RETRY

credits: Non executable stack support from Simon Spooner
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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

* MMU I-TLB / D-TLB Miss Exceptions
  - Fast Path TLB Refill Handler
  - slowpath TLB creation via do_page_fault() -> update_mmu_cache()
* Duplicate PD Exception Handler
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

ARC700 MMU provides for tagging TLB entries with a 8-bit ASID to avoid
having to flush the TLB every task switch.

It also allows for a quick way to invalidate all the TLB entries for
task useful for:
* COW sementics during fork()
* task exit()ing
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

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