Files
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

99 lines
2.1 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* locks.S: SMP low-level lock primitives on Sparc.
*
* Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1998 Anton Blanchard (anton@progsoc.uts.edu.au)
* Copyright (C) 1998 Jakub Jelinek (jj@ultra.linux.cz)
*/
#include <asm/ptrace.h>
#include <asm/psr.h>
#include <asm/smp.h>
#include <asm/spinlock.h>
#include <asm/export.h>
.text
.align 4
/* Read/writer locks, as usual this is overly clever to make it
* as fast as possible.
*/
/* caches... */
___rw_read_enter_spin_on_wlock:
orcc %g2, 0x0, %g0
be,a ___rw_read_enter
ldstub [%g1 + 3], %g2
b ___rw_read_enter_spin_on_wlock
ldub [%g1 + 3], %g2
___rw_read_try_spin_on_wlock:
andcc %g2, 0xff, %g0
be,a ___rw_read_try
ldstub [%g1 + 3], %g2
xnorcc %g2, 0x0, %o0 /* if g2 is ~0, set o0 to 0 and bugger off */
bne,a ___rw_read_enter_spin_on_wlock
ld [%g1], %g2
retl
mov %g4, %o7
___rw_read_exit_spin_on_wlock:
orcc %g2, 0x0, %g0
be,a ___rw_read_exit
ldstub [%g1 + 3], %g2
b ___rw_read_exit_spin_on_wlock
ldub [%g1 + 3], %g2
___rw_write_enter_spin_on_wlock:
orcc %g2, 0x0, %g0
be,a ___rw_write_enter
ldstub [%g1 + 3], %g2
b ___rw_write_enter_spin_on_wlock
ld [%g1], %g2
.globl ___rw_read_enter
EXPORT_SYMBOL(___rw_read_enter)
___rw_read_enter:
orcc %g2, 0x0, %g0
bne,a ___rw_read_enter_spin_on_wlock
ldub [%g1 + 3], %g2
ld [%g1], %g2
add %g2, 1, %g2
st %g2, [%g1]
retl
mov %g4, %o7
.globl ___rw_read_exit
EXPORT_SYMBOL(___rw_read_exit)
___rw_read_exit:
orcc %g2, 0x0, %g0
bne,a ___rw_read_exit_spin_on_wlock
ldub [%g1 + 3], %g2
ld [%g1], %g2
sub %g2, 0x1ff, %g2
st %g2, [%g1]
retl
mov %g4, %o7
.globl ___rw_read_try
EXPORT_SYMBOL(___rw_read_try)
___rw_read_try:
orcc %g2, 0x0, %g0
bne ___rw_read_try_spin_on_wlock
ld [%g1], %g2
add %g2, 1, %g2
st %g2, [%g1]
set 1, %o1
retl
mov %g4, %o7
.globl ___rw_write_enter
EXPORT_SYMBOL(___rw_write_enter)
___rw_write_enter:
orcc %g2, 0x0, %g0
bne ___rw_write_enter_spin_on_wlock
ld [%g1], %g2
andncc %g2, 0xff, %g0
bne,a ___rw_write_enter_spin_on_wlock
stb %g0, [%g1 + 3]
retl
mov %g4, %o7