Commit Graph

276 Commits

Author SHA1 Message Date
Vineet Gupta
8ccfe6675f ARC: split elf.h into uapi and export it for userspace
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-27 20:00:26 +05:30
Vineet Gupta
17139053eb ARC: Fixup the current ABI version
The upstream kernel ABI (v3) is different from current out-of-tree (v2):
* no-legacy-syscalls
* user_regs_struct layout has changed

So we rev up the ABI version

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-27 20:00:25 +05:30
Vineet Gupta
5dc99e50d2 ARC: gdbserver using regset interface possibly broken
ptrace regset interface relies on ELF_NGREG for ceiling the size of user
request. So any larger request (even if legit)  would be clipped.

The existing def of ELF_NGREG didn't use user_regs_struct and was
technically one placeholder short (stop_pc) - although the current code
would still work because pt_regs includes a bunch of extra fields,
making
      ELF_NGREG >= sizeof(struct user_regs_struct)/sizeof(long)

But we need to remove this ambiguity, specially since pt_regs should NOT
be directly associated with with anything userspace-ish.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-27 19:59:55 +05:30
Vineet Gupta
7e0d306c37 ARC: Kconfig cleanup tracking cross-arch Kconfig pruning in merge window
Since ARC port was not yet upstream, we missed a bunch of cross-arch
Kconfig removals:

* GENERIC_SIGALTSTACK: d64008a8f3 "burying unused conditionals"
* HAVE_IRQ_WORK: 6147a9d807 "irq_work: Remove CONFIG_HAVE_IRQ_WORK"
* ARCH_NO_VIRT_TO_BUS: e0cf2ef484 "arch Kconfig: centralise
                                   CONFIG_ARCH_NO_VIRT_TO_BUS"

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-26 14:25:22 +05:30
Vineet Gupta
eab6a08c08 ARC: make a copy of flat DT
The flat DT (currently embedded in vmlinux) is in .init section.
The unflattened/binary tree doesn't copy strings through and references
them from orig flat DT - which could cause catestrohpy if of_* APIs are
called post init, say from a driver which is a loadable module.

Reported-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-26 14:25:18 +05:30
Vineet Gupta
fc32781bfd ARC: [plat-arcfpga] DT arc-uart bindings change: "baud" => "current-speed"
Per Grant's review comment - driver changes via tty tree

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:22 +05:30
Vineet Gupta
70b319f2be ARC: Ensure CONFIG_VIRT_TO_BUS is not enabled
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Reported-by: James Hogan <james.hogan@imgtec.com>
2013-02-15 23:16:21 +05:30
Vineet Gupta
3eb3e7dd53 ARC: Fix pt_orig_r8 access
Syscall restarting fixes made pt_regs->orig_r8 a short word, which was
not reflected in the assembler code - thus could potentially break gdb
debugging.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:21 +05:30
Vineet Gupta
7f85e5ec0d ARC: [3.9] Fallout of hlist iterator update
Commit 0bbacca "hlist: drop the node parameter from iterators" changed
the iterator across the board - but ARC port being out-of-tree missed
it.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:20 +05:30
Vineet Gupta
1e26662993 ARC: 64bit RTSC timestamp hardware issue
The 64bit RTSC is not reliable, causing spurious "jumps" in higher word,
making Linux timekeeping go bonkers. So as of now just use the lower
32bit timestamp.

A cleaner approach would have been removing RTSC support altogether as the
32bit RTSC is equivalent to old TIMER1 based solution, but some customers
can use the 32bit RTSC in SMP syn fashion (vs. TIMER1 which being incore
can't be done easily).

A fallout of this is sched_clock()'s hardware assisted version needs to
go away since it can't use 32bit wrapping counter - instead we use the
generic "weak" jiffies based version.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:20 +05:30
Vineet Gupta
d626f547dd ARC: Don't fiddle with non-existent caches
!CONFIG_ARC_HAS_(I|D)CACHE makes Linux disable caches (assuming they
exist in hardware) - mostly for debugging issues with new peripherals.
However, independent of CONFIG_ARC_HAS_(I|D)CACHE, Linux also needs to
handle, non-existant caches, using the information in Cache BCRs (Build
Configuration Reg)

Reported-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:19 +05:30
Vineet Gupta
0208c96a9d ARC: Provide a default serial.h for uart drivers needing BASE_BAUD
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:18 +05:30
Vineet Gupta
95461a64e9 ARC: [plat-arcfpga] defconfig for fully loaded ARC Linux
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:17 +05:30
Vineet Gupta
b830cde5a4 ARC: [Review] Multi-platform image #8: platform registers SMP callbacks
Platforms export their SMP callbacks by populating arc_smp_ops.
The population itself needs to be done pretty early, from init_early
callback.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:17 +05:30
Vineet Gupta
10b1271875 ARC: [Review] Multi-platform image #7: SMP common code to use callbacks
This again is for switch from singleton platform SMP API to
multi-platform paradigm

Platform code is not yet setup to populate the callbacks, that happens
in next commit

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:16 +05:30
Vineet Gupta
fc7943d29e ARC: [Review] Multi-platform image #6: cpu-to-dma-addr optional
All the current platforms can work with 0x8000_0000 based dma_addr_t
since the Bus Bridges typically ignore the top bit (the only excpetion
was Angel4 PCI-AHB bridge which we no longer care for).
That way we don't need plat-specific cpu-addr to bus-addr conversion.

Hooks still provided - just in case a platform has an obscure device
which say needs 0 based bus address.

That way <asm/dma_mapping.h> no longer needs to unconditinally include
<plat/dma_addr.h>

Also verfied that on Angel4 board, other peripherals (IDE-disk / EMAC)
work fine with 0x8000_0000 based dma addresses.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:15 +05:30
Vineet Gupta
decae9d3e8 ARC: [Review] Multi-platform image #5: NR_IRQS defined by ARC core
For now this will suffice for all platforms, later exotic ones needs to
get this from DeviceTree

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:15 +05:30
Vineet Gupta
e97ff121ae ARC: [Review] Multi-platform image #4: Isolate platform headers
-Top level ARC makefile removes -I for platform headers
-asm/irq.h no longer includes plat/irq.h

-platform makefile adds -I for it's specfic platform headers
-platform code to directly include it's plat/irq.h

-Linker script needed plat/memmap.h for CCM info, already in .config

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:14 +05:30
Vineet Gupta
877768c84d ARC: [Review] Multi-platform image #3: switch to board callback
-platform API is retired and instead callbacks are used

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:14 +05:30
Vineet Gupta
03a6d28cdd ARC: [Review] Multi-platform image #2: Board callback Infrastructure
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: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:13 +05:30
Vineet Gupta
93ad700de2 ARC: Fold boards sub-menu into platform/SoC menu
This is more natural and is now doable since the choice constructs are
gone.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:13 +05:30
Vineet Gupta
53d98958f5 ARC: [Review] Multi-platform image #1: Kconfig enablement
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: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:12 +05:30
Gilad Ben-Yossef
4368902bb9 ARC: Add support for ioremap_prot API
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: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:11 +05:30
Vineet Gupta
8c2f4a8dd0 ARC: UAPI Disintegrate arch/arc/include/asm
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: Vineet Gupta <vgupta@synopsys.com>
Cc: David Howells <dhowells@redhat.com>
2013-02-15 23:16:11 +05:30
Vineet Gupta
cbe056f76a ARC: Hostlink Pseudo-Driver for Metaware Debugger
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:10 +05:30
Vineet Gupta
8b5850f8ac ARC: Support for single cycle Close Coupled Mem (CCM)
* 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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:10 +05:30
Vineet Gupta
9c57564e26 ARC: perf support (software counters only)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:09 +05:30
Vineet Gupta
7fadc1e8fe ARC: [plat-arfpga] BVCI Latency Unit setup
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:08 +05:30
Vineet Gupta
af61742813 ARC: Boot #2: Verbose Boot reporting / feature verification
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:07 +05:30
Mischa Jonker
f46121bd26 ARC: kgdb support
Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
2013-02-15 23:16:07 +05:30
Vineet Gupta
2e651ea159 ARC: Unaligned access emulation
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: Vineet Gupta <vgupta@synopsys.com>
Cc: Tim Yao <tim.yao@amlogic.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:16:06 +05:30
Vineet Gupta
4d86dfbbda ARC: kprobes support
Origin port done by Rajeshwar Ranga

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
2013-02-15 23:16:05 +05:30
Vineet Gupta
e65ab5a875 ARC: disassembly (needed by kprobes/kgdb/unaligned-access-emul)
In-kernel disassembler

Due Credits
* Orig written by Rajeshwar Ranga
* Consolidation/cleanups by Mischa Jonker

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
Cc: Mischa Jonker <mjonker@synopsys.com>
2013-02-15 23:16:04 +05:30
Vineet Gupta
44c8bb9140 ARC: stacktracing APIs based on dw2 unwinder
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:04 +05:30
Vineet Gupta
854a0d9505 ARC: DWARF2 .debug_frame based stack unwinder
-Originally written by Rajeshwar Ranga
-Derived off of generic unwinder in 2.6.19 and adapted to ARC

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
2013-02-15 23:16:03 +05:30
Vineet Gupta
41195d236e ARC: SMP support
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: Vineet 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>
2013-02-15 23:16:02 +05:30
Vineet Gupta
0ef88a54aa ARC: Diagnostics: show_regs() etc
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:02 +05:30
Vineet Gupta
fa1c3ff935 ARC: Module support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:01 +05:30
Vineet Gupta
4788a5942b ARC: Support for high priority interrupts in the in-core intc
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:01 +05:30
Vineet Gupta
769bc1fd7b ARC: OProfile support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Robert Richter <rric@kernel.org>
Cc: oprofile-list@lists.sf.net
Reviewed-by: James Hogan <james.hogan@imgtec.com>
2013-02-15 23:16:00 +05:30
Vineet Gupta
01b812bcce ARC: Futex support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:16:00 +05:30
Vineet Gupta
547f112571 ARC: ptrace support
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:15:59 +05:30
Vineet Gupta
080c37473e ARC: [optim] Cache "current" in Register r25
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:58 +05:30
Vineet Gupta
8872e9e513 ARC: [plat-arcfpga] defconfig
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:58 +05:30
Vineet Gupta
c08098f28e ARC: Last bits (stubs) to get to a running kernel with UART
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:57 +05:30
Vineet Gupta
abe11ddea1 ARC: [plat-arcfpga]: Enabling DeviceTree for Angel4 board
* 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: Vineet Gupta <vgupta@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:15:57 +05:30
Vineet Gupta
450dd430bf ARC: [DeviceTree] Convert some Kconfig items to runtime values
* mem size now runtime configured (prev CONFIG_ARC_PLAT_SDRAM_SIZE)
* core cpu clk runtime configured (prev CONFIG_ARC_PLAT_CLK)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@secretlab.ca>
2013-02-15 23:15:56 +05:30
Vineet Gupta
999159a538 ARC: [DeviceTree] Basic support
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: Vineet 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: Rob Herring <rob.herring@calxeda.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
2013-02-15 23:15:55 +05:30
Vineet Gupta
ee36d17221 ARC: [plat-arcfpga] Static platform device for CONFIG_SERIAL_ARC
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: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:15:55 +05:30
Vineet Gupta
c121c5063c ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-15 23:15:54 +05:30
Vineet Gupta
1162b0701b ARC: I/O and DMA Mappings
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:54 +05:30
Vineet Gupta
fbd7053a78 ARC: Page Fault handling
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:53 +05:30
Vineet Gupta
d79e678d74 ARC: TLB flush Handling
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:53 +05:30
Vineet Gupta
cc562d2eae ARC: MMU Exception Handling
* 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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:52 +05:30
Vineet Gupta
f1f3347da9 ARC: MMU Context Management
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: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:51 +05:30
Vineet Gupta
5dda4dc570 ARC: Page Table Management
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:51 +05:30
Vineet Gupta
95d6976d20 ARC: Cache Flush Management
* ARC700 has VIPT L1 Caches
* Caches don't snoop and are not coherent
* Given the PAGE_SIZE and Cache associativity, we don't support aliasing
  D$ configurations (yet), but do allow aliasing I$ configs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-15 23:15:50 +05:30
Vineet Gupta
55bb9480f9 ARC: [Review] Prevent incorrect syscall restarts
Per Al Viro's "signals for dummies" https://lkml.org/lkml/2012/12/6/366
there are 3 golden rules for (not) restarting syscalls:

"	What we need to guarantee is
* restarts do not happen on signals caught in interrupts or exceptions
* restarts do not happen on signals caught in sigreturn()
* restart should happen only once, even if we get through do_signal()
  many times."

ARC Port already handled #1, this patch fixes #2 and #3.

We use the additional state in pt_regs->orig_r8 to ckh if restarting
has already been done once.

Thanks to Al Viro for spotting this.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-15 23:15:50 +05:30
Vineet Gupta
5c39c0ab5e ARC: [Review] Preparing to fix incorrect syscall restarts due to signals
To avoid multiple syscall restarts (multiple signals) or no restart at
all (sigreturn), we need just an extra bit of state "literally 1 bit" in
struct pt_regs. orig_r8 is the best place to do this, however given the
way it is encoded currently, we can't add anything simplistically.

Current orig_r8:
* syscalls   -> 1 to NR_SYSCALLS
* Exceptions -> NR_SYSCALLS + 1
* Break-point-> NR_SYSCALLS + 2

In new scheme it is a bit-field
* lower short word contains the  exact event type (and a new bit to represent
   restart semantics : if syscall was already / can't be restarted)
* upper short word optionally containing the syscall num - needed by
  likes of tracehooks etc

This patch only changes how orig_r8 is organised and nothing should
change behaviourily.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-15 23:15:49 +05:30
Vineet Gupta
c3581039b6 ARC: Signal handling
Includes following fixes courtesy review by Al-Viro

* Tracer poke to Callee-regs were lost

  Before going off into do_signal( ) we save the user-mode callee regs
  (as they are not saved by default as part of pt_regs). This is to make
  sure that that a Tracer (if tracing related signal) is able to do likes
  of PEEKUSR(callee-reg).

  However in return path we were simply discarding the user-mode callee
  regs, which would break a POKEUSR(callee-reg) from a tracer.

* Issue related to multiple syscall restarts are addressed in next patch

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Jonas Bonn <jonas@southpole.se>
2013-02-15 23:03:30 +05:30
Vineet Gupta
d8005e6b95 ARC: Timers/counters/delay management
ARC700 includes 2 in-core 32bit timers TIMER0 and TIMER1.
Both have exactly same capabilies.

* programmable to count from TIMER<n>_CNT to TIMER<n>_LIMIT
* for count 0 and LIMIT ~1, provides a free-running counter by
    auto-wrapping when limit is reached.
* optionally interrupt when LIMIT is reached (oneshot event semantics)
* rearming the interrupt provides periodic semantics
* run at CPU clk

ARC Linux uses TIMER0 for clockevent (periodic/oneshot) and TIMER1 for
clocksource (free-running clock).

Newer cores provide RTSC insn which gives a 64bit cpu clk snapshot hence
is more apt for clocksource when available.

SMP poses a bit of challenge for global timekeeping clocksource /
sched_clock() backend:
 -TIMER1 based local clocks are out-of-sync hence can't be used
  (thus we default to jiffies based cs as well as sched_clock() one/both
  of which platform can override with it's specific hardware assist)
 -RTSC is only allowed in SMP if it's cross-core-sync (Kconfig glue
  ensures that) and thus usable for both requirements.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-02-11 20:00:39 +05:30
Vineet Gupta
bf90e1eab6 ARC: Process-creation/scheduling/idle-loop
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-02-11 20:00:38 +05:30
Vineet Gupta
4adeefe161 ARC: Syscall support (no-legacy-syscall ABI)
This includes support for generic clone/for/vfork/execve

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-11 20:00:38 +05:30
Vineet Gupta
054419ed84 ARC: Non-MMU Exception Handling
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-11 20:00:37 +05:30
Vineet Gupta
bacdf4809a ARC: Interrupt Handling
This contains:
-bootup arch IRQ init: init_IRQ(), arc_init_IRQ()
-generic IRQ subsystem glue: arch_do_IRQ()
-basic IRQ chip setup for in-core intc

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-02-11 20:00:37 +05:30
Vineet Gupta
9d42c84f91 ARC: Low level IRQ/Trap/Exception Handling
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 20:00:36 +05:30
Vineet Gupta
5210d1e688 ARC: String library
Hand optimised asm code for ARC700 pipeline.
Originally written/optimized by Joern Rennecke

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Joern Rennecke <joern.rennecke@embecosm.com>
2013-02-11 20:00:35 +05:30
Vineet Gupta
6e35fa2d43 ARC: Spinlock/rwlock/mutex primitives
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-11 20:00:35 +05:30
Vineet Gupta
3be80aaef8 ARC: Fundamental ARCH data-types/defines
* L1_CACHE_SHIFT
* PAGE_SIZE, PAGE_OFFSET
* struct pt_regs, struct user_regs_struct
* struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ...
* struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ...
* BUG()
* ELF_*
* Elf_*

To disallow user-space visibility into some of the core kernel data-types
such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header
spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Jonas Bonn <jonas.bonn@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-11 20:00:34 +05:30
Vineet Gupta
ca15c8ecd5 ARC: Checksum/byteorder/swab routines
TBD: do_csum still needs to be written in asm

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-11 20:00:34 +05:30
Vineet Gupta
0a5eae458e ARC: [optim] uaccess __{get,put}_user() optimised
Override asm-generic implementations. We basically gain on 2 fronts

* checks for alignment no longer needed as we are only doing "unit"
  sized copies.

  (Careful observer could argue that While the kernel buffers are aligned,
   the user buffer in theory might not be - however in that case the
   user space is already broken when it tries to deref a hword/word
   straddling word boundary - so we are not making it any worse).

* __copy_{to,from}_user( ) returns bytes that couldn't be copied,
  whereas get_user() returns 0 for success or -EFAULT (not size). Thus
  the code to do leftover bytes calculation can be avoided as well.

The savings were significant: ~17k of code.

bloat-o-meter vmlinux_uaccess_pre vmlinux_uaccess_post
add/remove: 0/4 grow/shrink: 8/118 up/down: 1262/-18758 (-17496)
							^^^^^^^^^
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-02-11 20:00:32 +05:30
Vineet Gupta
43697cb097 ARC: uaccess friends
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-11 20:00:31 +05:30
Vineet Gupta
14e968bad7 ARC: Atomic/bitops/cmpxchg/barriers
This covers the UP / SMP (with no hardware assist for atomic r-m-w) as
well as ARC700 LLOCK/SCOND insns based.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-02-11 20:00:30 +05:30
Vineet Gupta
ac4c244d4e ARC: irqflags - Interrupt enabling/disabling at in-core intc
ARC700 has an in-core intc which provides 2 priorities (a.k.a.) "levels"
of interrupts (per IRQ) hencforth referred to as L1/L2 interrupts.

CPU flags register STATUS32 has Interrupt Enable bits per level (E1/E2)
to globally enable (or disable) all IRQs at a level. Hence the
implementation of arch_local_irq_{save,restore,enable,disable}( )

The STATUS32 reg can be r/w only using the AUX Interface of ARC, hence
the use of LR/SR instructions. Further, E1/E2 bits in there can only be
updated using the FLAG insn.

The intc supports 32 interrupts - and per IRQ enabling is controlled by
a bit in the AUX_IENABLE register, hence the implmentation of
arch_{,un}mask_irq( ) routines.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-02-11 20:00:30 +05:30
Vineet Gupta
cfdbc2e16e ARC: Build system: Makefiles, Kconfig, Linker script
Arnd in his review pointed out that arch Kconfig organisation has several
deficiencies:

* Build time entries for things which can be runtime extracted from DT
  (e.g. SDRAM size, core clk frequency..)
* Not multi-platform-image-build friendly (choice .. endchoice constructs)
* cpu variants support (750/770) is exclusive.

The first 2 have been fixed in subsequent patches.
Due to the nature of the 750 and 770, it is not possible to build for
both together, w/o special runtime glue code which would hurt
performance.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
2013-02-11 20:00:25 +05:30
Vineet Gupta
79a033c6b9 ARC: Generic Headers
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-01-28 12:34:21 +05:30