linux-toradex.git/arch/arc/kernel/asm-offsets.c, branch v6.7 Linux kernel for Apalis and Colibri modules ARC: pt_regs: create seperate type for ecr 2023-08-18T17:30:47+00:00 Vineet Gupta vgupta@kernel.org 2020-05-22T00:44:32+00:00 58d9ceb7d9f56bd74b8e904e26511d27a4220827 Reduces duplication in each ISA specific pt_regs Tested-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202308151342.ROQ9Urvv-lkp@intel.com Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
Reduces duplication in each ISA specific pt_regs

Tested-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202308151342.ROQ9Urvv-lkp@intel.com
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARCv2: entry: rearrange pt_regs slightly 2023-08-18T17:30:47+00:00 Vineet Gupta vgupta@kernel.org 2020-05-22T23:24:53+00:00 d4624bf6a6c9d9ff084eb2cba6d3cf6aeda9f974 Instead of r26,fp,sp,r12,r30 order as fp,r30,r12,r26,sp - keeps SP at well known position (right abive hardware autosave) - r26,r12 saved specifically for ARCv2 (and not in ARCv3) kept closer for easy ifdef'ry later Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
Instead of r26,fp,sp,r12,r30 order as fp,r30,r12,r26,sp

 - keeps SP at well known position (right abive hardware autosave)
 - r26,r12 saved specifically for ARCv2 (and not in ARCv3) kept
   closer for easy ifdef'ry later

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARC: entry: rework (non-functional) 2023-08-18T03:31:59+00:00 Vineet Gupta vgupta@kernel.org 2020-05-19T23:01:52+00:00 c505b0da76a67139e073a5a5c4a1986b1cf168d3 - comments update - rename syscall_trace_entry - use PT_xxx in entry code Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
 - comments update
 - rename syscall_trace_entry
 - use PT_xxx in entry code

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARC: __switch_to: move ksp to thread_info from thread_struct 2023-08-18T03:31:59+00:00 Vineet Gupta vgupta@kernel.org 2020-05-14T07:51:26+00:00 fd476197c63dd3aae85e286dab7da23b159562b9 task's arch specific bits are carried in 2 places - embedded thread_struct in task_struct - associated thread_info (hoisted in task's stack page) and syntactically: (thread_info *)(task_struct->stack) ksp (dynamic kernel stack top) currently lives in thread_struct but given its deep location in task struct likely to cache miss when accessed from __switch_to(). Moving it to thread_info would be more efficient given proximity to frequently accessed items such as preempt_count thus very likely to be in cache, specially in schedular code. Note however that currently tsk.thread.ksp takes 1 memory access (off of tsk pointer) while new code tsk->stack.ksp would take 2, but likely to be in cache. Moreover if task is current the 2nd reference can be elided and instead derived from SP as (SP & ~(THREAD_SIZE - 1)) All of this also makes __switch_to() code simpler and we can see the 2 ways of retirving ksp (descrobed above) in new code. Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
task's arch specific bits are carried in 2 places
 - embedded thread_struct in task_struct
 - associated thread_info (hoisted in task's stack page) and
   syntactically: (thread_info *)(task_struct->stack)

ksp (dynamic kernel stack top) currently lives in thread_struct but
given its deep location in task struct likely to cache miss when
accessed from  __switch_to(). Moving it to thread_info would be more
efficient given proximity to frequently accessed items such as
preempt_count thus very likely to be in cache, specially in schedular
code.

Note however that currently tsk.thread.ksp takes 1 memory access (off
of tsk pointer) while new code tsk->stack.ksp would take 2, but likely
to be in cache. Moreover if task is current the 2nd reference can be
elided and instead derived from SP as (SP & ~(THREAD_SIZE - 1))

All of this also makes __switch_to() code simpler and we can see the 2
ways of retirving ksp (descrobed above) in new code.

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARC: entry: use gp to cache task pointer (vs. r25) 2023-08-18T03:31:59+00:00 Vineet Gupta vgupta@kernel.org 2020-05-13T05:18:08+00:00 cfca4b5abe0cc13f9d9f45f760efd8260e31200f The motivation is eventual ABI considerations for ARCv3 but even without it this change us worthwhile as diffstat reduces 100 net lines r25 is a callee saved register, normally not saved by entry code in pt_regs. However because of its usage in CONFIG_ARC_CURR_IN_REG it needs to be. This in turn requires a whole bunch of special casing when we need to access r25. Then there is distinction between user mode r25 vs. kernel mode r25 - hence distinct SAVE_CALLEE_SAVED_{USER,KERNEL} Instead use gp which is a scratch register and thus saved already in entry code. This cleans things up significantly and much nocer on eyes: - SAVE_CALLEE_SAVED_{USER,KERNEL} are now exactly same - no special user_r25 slot in pt_reggs Note that typical global asm registers are callee-saved (r25), but gp is not callee-saved thus needs additional -ffixed-<reg> toggle Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
The motivation is eventual ABI considerations for ARCv3 but even without
it this change us worthwhile as diffstat reduces 100 net lines

r25 is a callee saved register, normally not saved by entry code in
pt_regs. However because of its usage in CONFIG_ARC_CURR_IN_REG it needs
to be. This in turn requires a whole bunch of special casing when we
need to access r25. Then there is distinction between user mode r25 vs.
kernel mode r25 - hence distinct SAVE_CALLEE_SAVED_{USER,KERNEL}

Instead use gp which is a scratch register and thus saved already in entry
code. This cleans things up significantly and much nocer on eyes:

 - SAVE_CALLEE_SAVED_{USER,KERNEL} are now exactly same
 - no special user_r25 slot in pt_reggs

Note that typical global asm registers are callee-saved (r25), but gp is
not callee-saved thus needs additional -ffixed-<reg> toggle

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARC: add support for DSP-enabled userspace applications 2020-03-16T17:30:49+00:00 Eugeniy Paltsev Eugeniy.Paltsev@synopsys.com 2020-03-05T20:02:51+00:00 7321e2ea0d6aece516a9c0827028ecda2ccaeae9 To be able to run DSP-enabled userspace applications we need to save and restore following DSP-related registers: At IRQ/exception entry/exit: * DSP_CTRL (save it and reset to value suitable for kernel) * ACC0_LO, ACC0_HI (we already save them as r58, r59 pair) At context switch: * ACC0_GLO, ACC0_GHI * DSP_BFLY0, DSP_FFT_CTRL Reviewed-by: Vineet Gupta <vgupta@synopsys.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 we need to
save and restore following DSP-related registers:
At IRQ/exception entry/exit:
 * DSP_CTRL (save it and reset to value suitable for kernel)
 * ACC0_LO, ACC0_HI (we already save them as r58, r59 pair)
At context switch:
 * ACC0_GLO, ACC0_GHI
 * DSP_BFLY0, DSP_FFT_CTRL

Reviewed-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC: pt_regs: remove hardcoded registers offset 2019-12-28T21:05:08+00:00 Eugeniy Paltsev Eugeniy.Paltsev@synopsys.com 2019-12-27T18:03:43+00:00 7ecc6c1d5c8dbc713c647512a5267ca0eafe3e1c Replace hardcoded registers offset numbers by calculated via offsetof. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
Replace hardcoded registers offset numbers by calculated via
offsetof.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC: asm-offsets: remove duplicate entry 2019-12-19T14:48:58+00:00 Eugeniy Paltsev Eugeniy.Paltsev@synopsys.com 2019-12-19T13:30:40+00:00 833a20b8d4924b63ef7700e43fe4941963002822 We define 'PT_user_r25' twice in asm-offsets.c It's not a big issue as we define it to the same value, however let's fix it. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
We define 'PT_user_r25' twice in asm-offsets.c
It's not a big issue as we define it to the same value, however
let's fix it.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARCv2: entry: rewrite to enable use of double load/stores LDD/STD 2019-07-01T18:02:22+00:00 Vineet Gupta vgupta@synopsys.com 2019-05-15T22:36:46+00:00 a4880801a72ecc2dcdfa432f81a754f3e7438567 - the motivation was to be remove blatent copy-paste due to hasty support of CONFIG_ARC_IRQ_NO_AUTOSAVE support - but with refactoring we could use LDD/STD to greatly optimize the code Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
 - the motivation was to be remove blatent copy-paste due to hasty support
   of CONFIG_ARC_IRQ_NO_AUTOSAVE support

 - but with refactoring we could use LDD/STD to greatly optimize the code

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19T15:09:55+00:00 Thomas Gleixner tglx@linutronix.de 2019-06-04T08:11:33+00:00 d2912cb15bdda8ba4a5dd73396ad62641af2f520 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 <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>