linux.git/arch/arc/kernel/Makefile, branch v6.12.80

ARC: __switch_to: asm with dwarf ops (vs. inline asm)

2023-08-18T03:31:59+00:00

__switch_to() is final step of context switch, swapping kernel modes
stack (and callee regs) of outgoing task with next task.

It is also the starting point of stack unwinging of a sleeping task and
captures SP, FP, BLINK and the corresponding dwarf info. Back when
dinosaurs still roamed around, ARC gas didn't support CFI pseudo ops and
gcc was responsible for generating dwarf info. Thus it had to be written
in "C" with inline asm to do the hand crafting of stack. The function
prologue (and crucial saving of blink etc) was still gcc generated but
not visible in code. Likewise dwarf info was missing.

Now with modern tools, we can make things more obvious by writing the
code in asm and adding approproate dwarf cfi pseudo ops.

This is mostly non functional change, except for slight chnages to asm

 - ARCompact doesn't support MOV_S fp, sp, so we use MOV

Signed-off-by: Vineet Gupta

kbuild: use obj-y instead extra-y for objects placed at the head

2022-10-02T09:04:05+00:00

The objects placed at the head of vmlinux need special treatments:

 - arch/$(SRCARCH)/Makefile adds them to head-y in order to place
   them before other archives in the linker command line.

 - arch/$(SRCARCH)/kernel/Makefile adds them to extra-y instead of
   obj-y to avoid them going into built-in.a.

This commit gets rid of the latter.

Create vmlinux.a to collect all the objects that are unconditionally
linked to vmlinux. The objects listed in head-y are moved to the head
of vmlinux.a by using 'ar m'.

With this, arch/$(SRCARCH)/kernel/Makefile can consistently use obj-y
for builtin objects.

There is no *.o that is directly linked to vmlinux. Drop unneeded code
in scripts/clang-tools/gen_compile_commands.py.

$(AR) mPi needs 'T' to workaround the llvm-ar bug. The fix was suggested
by Nathan Chancellor [1].

[1]: https://lore.kernel.org/llvm/YyjjT5gQ2hGMH0ni@dev-arch.thelio-3990X/

Signed-off-by: Masahiro Yamada 
Tested-by: Nick Desaulniers 
Reviewed-by: Nicolas Schier

arc: ptrace: hard-code "arc" instead of UTS_MACHINE

2020-04-13T05:27:09+00:00

ARC uses the UTS_MACHINE defined in the top Makefile as follows:

  UTS_MACHINE     := $(ARCH)

We know it is "arc" when we are building the kernel for ARC.
Hard-code user_regset_view::name, like many other architectures do.

Signed-off-by: Masahiro Yamada 
Signed-off-by: Vineet Gupta

ARCv2: fpu: preserve userspace fpu state

2020-01-18T00:53:44+00:00

Signed-off-by: Vineet Gupta

ARC: ARCv2: jump label: implement jump label patching

2019-11-09T00:14:32+00:00

Implement jump label patching for ARC. Jump labels provide
an interface to generate dynamic branches using
self-modifying code.

This allows us to implement conditional branches where
changing branch direction is expensive but branch selection
is basically 'free'

This implementation uses 32-bit NOP and BRANCH instructions
which forced to be aligned by 4 to guarantee that they don't
cross L1 cache line boundary and can be update atomically.

Signed-off-by: Eugeniy Paltsev 
Signed-off-by: Vineet Gupta

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Enrico Weigelt 
Reviewed-by: Kate Stewart 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ARC: Remove empty kernel/pcibios.c

2017-08-02T19:53:35+00:00

ARC requires no arch-specific pcibios hooks, so delete this empty file.

Signed-off-by: Palmer Dabbelt 
Signed-off-by: Bjorn Helgaas

clocksource: import ARC timer driver

2016-11-30T19:54:25+00:00

This adds support for

 - CONFIG_ARC_TIMERS : legacy 32-bit TIMER0 and TIMER1 which count UP
   from @CNT to @LIMIT, before optionally triggering an interrupt.
   These are programmed using ARC auxiliary register interface.
   These are present in all ARC cores (ARC700 and ARC HS38)
   TIMER0 serves as clockevent for all ARC linux builds.
   TIMER1 is used for clocksource in arc700 builds.

 - CONFIG_ARC_TIMERS_64BIT: 64-bit counters, RTC and GFRC found in
   ARC HS38 cores. These are independnet IP blocks with different
   programming model respectively.

Link: http://lkml.kernel.org/r/20161111231132.GA4186@mai
Acked-by: Daniel Lezcano 
Signed-off-by: Vineet Gupta

ARC: RIP arc_{get|set}_core_freq() clk API

2016-05-09T04:02:31+00:00

There are no more users of this - so RIP!

Signed-off-by: Alexey Brodkin 
[vgupta: update changelog]
Signed-off-by: Vineet Gupta

ARC: Add PCI support

2016-03-10T20:44:13+00:00

Add PCI support to ARC and update drivers/pci Makefile enabling the ARC
arch to use the generic PCI setup functions.

[bhelgaas: fold in Joao's pci-dma-compat.h & pci-bridge.h build fix (I
should have caught this myself, sorry]
Signed-off-by: Joao Pinto 
Signed-off-by: Bjorn Helgaas 
Acked-by: Vineet Gupta