linux/arch/arm/mach-tegra/sleep.S
Nick Desaulniers a2faac3986 ARM: 9263/1: use .arch directives instead of assembler command line flags
Similar to commit a6c30873ee ("ARM: 8989/1: use .fpu assembler
directives instead of assembler arguments").

GCC and GNU binutils support setting the "sub arch" via -march=,
-Wa,-march, target function attribute, and .arch assembler directive.

Clang was missing support for -Wa,-march=, but this was implemented in
clang-13.

The behavior of both GCC and Clang is to
prefer -Wa,-march= over -march= for assembler and assembler-with-cpp
sources, but Clang will warn about the -march= being unused.

clang: warning: argument unused during compilation: '-march=armv6k'
[-Wunused-command-line-argument]

Since most assembler is non-conditionally assembled with one sub arch
(modulo arch/arm/delay-loop.S which conditionally is assembled as armv4
based on CONFIG_ARCH_RPC, and arch/arm/mach-at91/pm-suspend.S which is
conditionally assembled as armv7-a based on CONFIG_CPU_V7), prefer the
.arch assembler directive.

Add a few more instances found in compile testing as found by Arnd and
Nathan.

Link: 1d51c699b9
Link: https://bugs.llvm.org/show_bug.cgi?id=48894
Link: https://github.com/ClangBuiltLinux/linux/issues/1195
Link: https://github.com/ClangBuiltLinux/linux/issues/1315

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
2022-11-08 18:36:17 +00:00

153 lines
3.2 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* arch/arm/mach-tegra/sleep.S
*
* Copyright (c) 2010-2011, NVIDIA Corporation.
* Copyright (c) 2011, Google, Inc.
*
* Author: Colin Cross <ccross@android.com>
* Gary King <gking@nvidia.com>
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/cache.h>
#include <asm/cp15.h>
#include <asm/hardware/cache-l2x0.h>
#include "iomap.h"
#include "sleep.h"
#define CLK_RESET_CCLK_BURST 0x20
#define CLK_RESET_CCLK_DIVIDER 0x24
.arch armv7-a
#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
/*
* tegra_disable_clean_inv_dcache
*
* disable, clean & invalidate the D-cache
*
* Corrupted registers: r1-r3, r6, r8, r9-r11
*/
ENTRY(tegra_disable_clean_inv_dcache)
stmfd sp!, {r0, r4-r5, r7, r9-r11, lr}
dmb @ ensure ordering
/* Disable the D-cache */
mrc p15, 0, r2, c1, c0, 0
tst r2, #CR_C @ see tegra_sleep_cpu()
bic r2, r2, #CR_C
mcrne p15, 0, r2, c1, c0, 0
isb
/* Flush the D-cache */
cmp r0, #TEGRA_FLUSH_CACHE_ALL
blne v7_flush_dcache_louis
bleq v7_flush_dcache_all
/* Trun off coherency */
exit_smp r4, r5
ldmfd sp!, {r0, r4-r5, r7, r9-r11, pc}
ENDPROC(tegra_disable_clean_inv_dcache)
#endif
#ifdef CONFIG_PM_SLEEP
/*
* tegra_init_l2_for_a15
*
* set up the correct L2 cache data RAM latency
*/
ENTRY(tegra_init_l2_for_a15)
mrc p15, 0, r0, c0, c0, 5
ubfx r0, r0, #8, #4
tst r0, #1 @ only need for cluster 0
bne _exit_init_l2_a15
mrc p15, 0x1, r0, c9, c0, 2
and r0, r0, #7
cmp r0, #2
bicne r0, r0, #7
orrne r0, r0, #2
mcrne p15, 0x1, r0, c9, c0, 2
_exit_init_l2_a15:
ret lr
ENDPROC(tegra_init_l2_for_a15)
/*
* tegra_sleep_cpu_finish(unsigned long v2p)
*
* enters suspend in LP2 by turning off the mmu and jumping to
* tegra?_tear_down_cpu
*/
ENTRY(tegra_sleep_cpu_finish)
mov r4, r0
/* Flush and disable the L1 data cache */
mov r0, #TEGRA_FLUSH_CACHE_ALL
bl tegra_disable_clean_inv_dcache
mov r0, r4
mov32 r6, tegra_tear_down_cpu
ldr r1, [r6]
add r1, r1, r0
mov32 r3, tegra_shut_off_mmu
add r3, r3, r0
mov r0, r1
ret r3
ENDPROC(tegra_sleep_cpu_finish)
/*
* tegra_shut_off_mmu
*
* r0 = physical address to jump to with mmu off
*
* called with VA=PA mapping
* turns off MMU, icache, dcache and branch prediction
*/
.align L1_CACHE_SHIFT
.pushsection .idmap.text, "ax"
ENTRY(tegra_shut_off_mmu)
mrc p15, 0, r3, c1, c0, 0
movw r2, #CR_I | CR_Z | CR_C | CR_M
bic r3, r3, r2
dsb
mcr p15, 0, r3, c1, c0, 0
isb
#ifdef CONFIG_CACHE_L2X0
/* Disable L2 cache */
check_cpu_part_num 0xc09, r9, r10
retne r0
mov32 r2, TEGRA_ARM_PERIF_BASE + 0x3000
ldr r3, [r2, #L2X0_CTRL]
tst r3, #L2X0_CTRL_EN @ see tegra_sleep_cpu()
mov r3, #0
strne r3, [r2, #L2X0_CTRL]
#endif
ret r0
ENDPROC(tegra_shut_off_mmu)
.popsection
/*
* tegra_switch_cpu_to_pllp
*
* In LP2 the normal cpu clock pllx will be turned off. Switch the CPU to pllp
*/
ENTRY(tegra_switch_cpu_to_pllp)
/* in LP2 idle (SDRAM active), set the CPU burst policy to PLLP */
mov32 r5, TEGRA_CLK_RESET_BASE
mov r0, #(2 << 28) @ burst policy = run mode
orr r0, r0, #(4 << 4) @ use PLLP in run mode burst
str r0, [r5, #CLK_RESET_CCLK_BURST]
mov r0, #0
str r0, [r5, #CLK_RESET_CCLK_DIVIDER]
ret lr
ENDPROC(tegra_switch_cpu_to_pllp)
#endif