/* SPDX-License-Identifier: GPL-2.0-only */
/*
* arch/arm/include/asm/assembler.h
*
* Copyright (C) 1996-2000 Russell King
*
* This file contains arm architecture specific defines
* for the different processors.
*
* Do not include any C declarations in this file - it is included by
* assembler source.
*/
#ifndef __ASM_ASSEMBLER_H__
#define __ASM_ASSEMBLER_H__
#ifndef __ASSEMBLY__
#error "Only include this from assembly code"
#endif
#include <asm/ptrace.h>
#include <asm/opcodes-virt.h>
#include <asm/asm-offsets.h>
#include <asm/page.h>
#include <asm/thread_info.h>
#include <asm/uaccess-asm.h>
#define IOMEM(x) (x)
/*
* Endian independent macros for shifting bytes within registers.
*/
#ifndef __ARMEB__
#define lspull lsr
#define lspush lsl
#define get_byte_0 lsl #0
#define get_byte_1 lsr #8
#define get_byte_2 lsr #16
#define get_byte_3 lsr #24
#define put_byte_0 lsl #0
#define put_byte_1 lsl #8
#define put_byte_2 lsl #16
#define put_byte_3 lsl #24
#else
#define lspull lsl
#define lspush lsr
#define get_byte_0 lsr #24
#define get_byte_1 lsr #16
#define get_byte_2 lsr #8
#define get_byte_3 lsl #0
#define put_byte_0 lsl #24
#define put_byte_1 lsl #16
#define put_byte_2 lsl #8
#define put_byte_3 lsl #0
#endif
/* Select code for any configuration running in BE8 mode */
#ifdef CONFIG_CPU_ENDIAN_BE8
#define ARM_BE8(code...) code
#else
#define ARM_BE8(code...)
#endif
/*
* Data preload for architectures that support it
*/
#if __LINUX_ARM_ARCH__ >= 5
#define PLD(code...) code
#else
#define PLD(code...)
#endif
/*
* This can be used to enable code to cacheline align the destination
* pointer when bulk writing to memory. Experiments on StrongARM and
* XScale didn't show this a worthwhile thing to do when the cache is not
* set to write-allocate (this would need further testing on XScale when WA
* is used).
*
* On Feroceon there is much to gain however, regardless of cache mode.
*/
#ifdef CONFIG_CPU_FEROCEON
#define CALGN(code...) code
#else
#define CALGN(code...)
#endif
#define IMM12_MASK 0xfff
/* the frame pointer used for stack unwinding */
ARM( fpreg .req r11 )
THUMB( fpreg .req r7 )
/*
* Enable and disable interrupts
*/
#if __LINUX_ARM_ARCH__ >= 6
.macro disable_irq_notrace
cpsid i
.endm
.macro enable_irq_notrace
cpsie i
.endm
#else
.macro disable_irq_notrace
msr cpsr_c, #PSR_I_BIT | SVC_MODE
.endm
.macro enable_irq_notrace
msr cpsr_c, #SVC_MODE
.endm
#endif
#if __LINUX_ARM_ARCH__ < 7
.macro dsb, args
mcr p15, 0, r0, c7, c10, 4
.endm
.macro isb, args
mcr p15, 0, r0, c7, c5, 4
.endm
#endif
.macro asm_trace_hardirqs_off, save=1
#if defined(CONFIG_TRACE_IRQFLAGS)
.if \save
stmdb sp!, {r0-r3, ip, lr}
.endif
bl trace_hardirqs_off
.if \save
ldmia sp!, {r0-r3, ip, lr}
.endif
#endif
.endm
.macro asm_trace_hardirqs_on, cond=al, save=1
#if defined(CONFIG_TRACE_IRQFLAGS)
/*
* actually the registers should be pushed and pop'd conditionally, but
* after bl the flags are certainly clobbered
*/
.if \save
stmdb sp!, {r0-r3, ip, lr}
.endif
bl\cond trace_hardirqs_on
.if \save
ldmia sp!, {r0-r3, ip, lr}
.endif
#endif
.endm
.macro disable_irq, save=1
disable_irq_notrace
asm_trace_hardirqs_off \save
.endm
.macro enable_irq
asm_trace_hardirqs_on
enable_irq_notrace
.endm
/*
* Save the current IRQ state and disable IRQs. Note that this macro
* assumes FIQs are enabled, and that the processor is in SVC mode.
*/
.macro save_and_disable_irqs, oldcpsr
#ifdef CONFIG_CPU_V7M
mrs \oldcpsr, primask
#else
mrs \oldcpsr, cpsr
#endif
disable_irq
.endm
.macro save_and_disable_irqs_notrace, oldcpsr
#ifdef CONFIG_CPU_V7M
mrs \oldcpsr, primask
#else
mrs \oldcpsr, cpsr
#endif
disable_irq_notrace
.endm
/*
* Restore interrupt state previously stored in a register. We don't
* guarantee that this will preserve the flags.
*/
.macro restore_irqs_notrace, oldcpsr
#ifdef CONFIG_CPU_V7M
msr primask, \oldcpsr
#else
msr cpsr_c, \oldcpsr
#endif
.endm
.macro restore_irqs, oldcpsr
tst \oldcpsr, #PSR_I_BIT
asm_trace_hardirqs_on cond=eq
restore_irqs_notrace \oldcpsr
.endm
/*
* Assembly version of "adr rd, BSYM(sym)". This should only be used to
* reference local symbols in the same assembly file which are to be
* resolved by the assembler. Other usage is undefined.
*/
.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
.macro badr\c, rd, sym
#ifdef CONFIG_THUMB2_KERNEL
adr\c \rd, \sym + 1
#else
adr\c \rd, \sym
#endif
.endm
.endr
/*
* Get current thread_info.
*/
.macro get_thread_info, rd
/* thread_info is the first member of struct task_struct */
get_current \rd
.endm
/*
* Increment/decrement the preempt count.
*/
#ifdef CONFIG_PREEMPT_COUNT
.macro inc_preempt_count, ti, tmp
ldr \tmp, [\ti, #TI_PREEMPT] @ get preempt count
add \tmp, \tmp, #1 @ increment it
str \tmp, [\ti, #TI_PREEMPT]
.endm
.macro dec_preempt_count, ti, tmp
ldr \tmp, [\ti, #TI_PREEMPT] @ get preempt count
sub \tmp, \tmp, #1 @ decrement it
str \tmp, [\ti, #TI_PREEMPT]
.endm
#else
.macro inc_preempt_count, ti, tmp
.endm
.macro dec_preempt_count, ti, tmp
.endm
#endif
#define USERL(l, x...) \
9999: x; \
.pushsection __ex_table,"a"; \
.align 3; \
.long 9999b,l; \
.popsection
#define USER(x...) USERL(9001f, x)
#ifdef CONFIG_SMP
#define ALT_SMP(instr...) \
9998: instr
/*
* Note: if you get assembler errors from ALT_UP() when building with
* CONFIG_THUMB2_KERNEL, you almost certainly need to use
* ALT_SMP( W(instr) ... )
*/
#define ALT_UP(instr...) \
.pushsection ".alt.smp.init", "a" ;\
.align 2 ;\
.long 9998b - . ;\
9997: instr ;\
.if . - 9997b == 2 ;\
nop ;\
.endif ;\
.if . - 9997b != 4 ;\
.error "ALT_UP() content must assemble to exactly 4 bytes";\
.endif ;\
.popsection
#define ALT_UP_B(label) \
.pushsection ".alt.smp.init", "a" ;\
.align 2 ;\
.long 9998b - . ;\
W(b) . + (label - 9998b) ;\
.popsection
#else
#define ALT_SMP(instr...)
#define ALT_UP(instr...) instr
#define ALT_UP_B(label) b label
#endif
/*
* this_cpu_offset - load the per-CPU offset of this CPU into
* register 'rd'
*/
.macro this_cpu_offset, rd:req
#ifdef CONFIG_SMP
ALT_SMP(mrc p15, 0, \rd, c13, c0, 4)
#ifdef CONFIG_CPU_V6
ALT_UP_B(.L1_\@)
.L0_\@:
.subsection 1
.L1_\@: ldr_va \rd, __per_cpu_offset
b .L0_\@
.previous
#endif
#else
mov \rd, #0
#endif
.endm
/*
* set_current - store the task pointer of this CPU's current task
*/
.macro set_current, rn:req, tmp:req
#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
9998: mcr p15, 0, \rn, c13, c0, 3 @ set TPIDRURO register
#ifdef CONFIG_CPU_V6
ALT_UP_B(.L0_\@)
.subsection 1
.L0_\@: str_va \rn, __current, \tmp
b .L1_\@
.previous
.L1_\@:
#endif
#else
str_va \rn, __current, \tmp
#endif
.endm
/*
* get_current - load the task pointer of this CPU's current task
*/
.macro get_current, rd:req
#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
9998: mrc p15, 0, \rd, c13, c0, 3 @ get TPIDRURO register
#ifdef CONFIG_CPU_V6
ALT_UP_B(.L0_\@)
.subsection 1
.L0_\@: ldr_va \rd, __current
b .L1_\@
.previous
.L1_\@:
#endif
#else
ldr_va \rd, __current
#endif
.endm
/*
* reload_current - reload the task pointer of this CPU's current task
* into the TLS register
*/
.macro reload_current, t1:req, t2:req
#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
#ifdef CONFIG_CPU_V6
ALT_SMP(nop)
ALT_UP_B(.L0_\@)
#endif
ldr_this_cpu \t1, __entry_task, \t1, \t2
mcr p15, 0, \t1, c13, c0, 3 @ store in TPIDRURO
.L0_\@:
#endif
.endm
/*
* Instruction barrier
*/
.macro instr_sync
#if __LINUX_ARM_ARCH__ >= 7
isb
#elif __LINUX_ARM_ARCH__ == 6
mcr p15, 0, r0, c7, c5, 4
#endif
.endm
/*
* SMP data memory barrier
*/
.macro smp_dmb mode
#ifdef CONFIG_SMP
#if __LINUX_ARM_ARCH__ >= 7
.ifeqs "\mode","arm"
ALT_SMP(dmb ish)
.else
ALT_SMP(W(dmb) ish)
.endif
#elif __LINUX_ARM_ARCH__ == 6
ALT_SMP(mcr p15, 0, r0, c7, c10, 5) @ dmb
#else
#error Incompatible SMP platform
#endif
.ifeqs "\mode","arm"
ALT_UP(nop)
.else
ALT_UP(W(nop))
.endif
#endif
.endm
/*
* Raw SMP data memory barrier
*/
.macro __smp_dmb mode
#if __LINUX_ARM_ARCH__ >= 7
.ifeqs "\mode","arm"
dmb ish
.else
W(dmb) ish
.endif
#elif __LINUX_ARM_ARCH__ == 6
mcr p15, 0, r0, c7, c10, 5 @ dmb
#else
.error "Incompatible SMP platform"
#endif
.endm
#if defined(CONFIG_CPU_V7M)
/*
* setmode is used to assert to be in svc mode during boot. For v7-M
* this is done in __v7m_setup, so setmode can be empty here.
*/
.macro setmode, mode, reg
.endm
#elif defined(CONFIG_THUMB2_KERNEL)
.macro setmode, mode, reg
mov \reg, #\mode
msr cpsr_c, \reg
.endm
#else
.macro setmode, mode, reg
msr cpsr_c, #\mode
.endm
#endif
/*
* Helper macro to enter SVC mode cleanly and mask interrupts. reg is
* a scratch register for the macro to overwrite.
*
* This macro is intended for forcing the CPU into SVC mode at boot time.
* you cannot return to the original mode.
*/
.macro safe_svcmode_maskall reg:req
#if __LINUX_ARM_ARCH__ >= 6 && !defined(CONFIG_CPU_V7M)
mrs \reg , cpsr
eor \reg, \reg, #HYP_MODE
tst \reg, #MODE_MASK
bic \reg , \reg , #MODE_MASK
orr \reg , \reg , #PSR_I_BIT | PSR_F_BIT | SVC_MODE
THUMB( orr \reg , \reg , #PSR_T_BIT )
bne 1f
orr \reg, \reg, #PSR_A_BIT
badr lr, 2f
msr spsr_cxsf, \reg
__MSR_ELR_HYP(14)
__ERET
1: msr cpsr_c, \reg
2:
#else
/*
* workaround for possibly broken pre-v6 hardware
* (akita, Sharp Zaurus C-1000, PXA270-based)
*/
setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, \reg
#endif
.endm
/*
* STRT/LDRT access macros with ARM and Thumb-2 variants
*/
#ifdef CONFIG_THUMB2_KERNEL
.macro usraccoff, instr, reg, ptr, inc, off, cond, abort, t=TUSER()
9999:
.if \inc == 1
\instr\()b\t\cond\().w \reg, [\ptr, #\off]
.elseif \inc == 4
\instr\t\cond\().w \reg, [\ptr, #\off]
.else
.error "Unsupported inc macro argument"
.endif
.pushsection __ex_table,"a"
.align 3
.long 9999b, \abort
.popsection
.endm
.macro usracc, instr, reg, ptr, inc, cond, rept, abort
@ explicit IT instruction needed because of the label
@ introduced by the USER macro
.ifnc \cond,al
.if \rept == 1
itt \cond
.elseif \rept == 2
ittt \cond
.else
.error "Unsupported rept macro argument"
.endif
.endif
@ Slightly optimised to avoid incrementing the pointer twice
usraccoff \instr, \reg, \ptr, \inc, 0, \cond, \abort
.if \rept == 2
usraccoff \instr, \reg, \ptr, \inc, \inc, \cond, \abort
.endif
add\cond \ptr, #\rept * \inc
.endm
#else /* !CONFIG_THUMB2_KERNEL */
.macro usracc, instr, reg, ptr, inc, cond, rept, abort, t=TUSER()
.rept \rept
9999:
.if \inc == 1
\instr\()b\t\cond \reg, [\ptr], #\inc
.elseif \inc == 4
\instr\t\cond \reg, [\ptr], #\inc
.else
.error "Unsupported inc macro argument"
.endif
.pushsection __ex_table,"a"
.align 3
.long 9999b, \abort
.popsection
.endr
.endm
#endif /* CONFIG_THUMB2_KERNEL */
.macro strusr, reg, ptr, inc, cond=al, rept=1, abort=9001f
usracc str, \reg, \ptr, \inc, \cond, \rept, \abort
.endm
.macro ldrusr, reg, ptr, inc, cond=al, rept=1, abort=9001f
usracc ldr, \reg, \ptr, \inc, \cond, \rept, \abort
.endm
/* Utility macro for declaring string literals */
.macro string name:req, string
.type \name , #object
\name:
.asciz "\string"
.size \name , . - \name
.endm
.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
.macro ret\c, reg
#if __LINUX_ARM_ARCH__ < 6
mov\c pc, \reg
#else
.ifeqs "\reg", "lr"
bx\c \reg
.else
mov\c pc, \reg
.endif
#endif
.endm
.endr
.macro ret.w, reg
ret \reg
#ifdef CONFIG_THUMB2_KERNEL
nop
#endif
.endm
.macro bug, msg, line
#ifdef CONFIG_THUMB2_KERNEL
1: .inst 0xde02
#else
1: .inst 0xe7f001f2
#endif
#ifdef CONFIG_DEBUG_BUGVERBOSE
.pushsection .rodata.str, "aMS", %progbits, 1
2: .asciz "\msg"
.popsection
.pushsection __bug_table, "aw"
.align 2
.word 1b, 2b
.hword \line
.popsection
#endif
.endm
#ifdef CONFIG_KPROBES
#define _ASM_NOKPROBE(entry) \
.pushsection "_kprobe_blacklist", "aw" ; \
.balign 4 ; \
.long entry; \
.popsection
#else
#define _ASM_NOKPROBE(entry)
#endif
.macro __adldst_l, op, reg, sym, tmp, c
.if __LINUX_ARM_ARCH__ < 7
ldr\c \tmp, .La\@
.subsection 1
.align 2
.La\@: .long \sym - .Lpc\@
.previous
.else
.ifnb \c
THUMB( ittt \c )
.endif
movw\c \tmp, #:lower16:\sym - .Lpc\@
movt\c \tmp, #:upper16:\sym - .Lpc\@
.endif
#ifndef CONFIG_THUMB2_KERNEL
.set .Lpc\@, . + 8 // PC bias
.ifc \op, add
add\c \reg, \tmp, pc
.else
\op\c \reg, [pc, \tmp]
.endif
#else
.Lb\@: add\c \tmp, \tmp, pc
/*
* In Thumb-2 builds, the PC bias depends on whether we are currently
* emitting into a .arm or a .thumb section. The size of the add opcode
* above will be 2 bytes when emitting in Thumb mode and 4 bytes when
* emitting in ARM mode, so let's use this to account for the bias.
*/
.set .Lpc\@, . + (. - .Lb\@)
.ifnc \op, add
\op\c \reg, [\tmp]
.endif
#endif
.endm
/*
* mov_l - move a constant value or [relocated] address into a register
*/
.macro mov_l, dst:req, imm:req, cond
.if __LINUX_ARM_ARCH__ < 7
ldr\cond \dst, =\imm
.else
movw\cond \dst, #:lower16:\imm
movt\cond \dst, #:upper16:\imm
.endif
.endm
/*
* adr_l - adr pseudo-op with unlimited range
*
* @dst: destination register
* @sym: name of the symbol
* @cond: conditional opcode suffix
*/
.macro adr_l, dst:req, sym:req, cond
__adldst_l add, \dst, \sym, \dst, \cond
.endm
/*
* ldr_l - ldr <literal> pseudo-op with unlimited range
*
* @dst: destination register
* @sym: name of the symbol
* @cond: conditional opcode suffix
*/
.macro ldr_l, dst:req, sym:req, cond
__adldst_l ldr, \dst, \sym, \dst, \cond
.endm
/*
* str_l - str <literal> pseudo-op with unlimited range
*
* @src: source register
* @sym: name of the symbol
* @tmp: mandatory scratch register
* @cond: conditional opcode suffix
*/
.macro str_l, src:req, sym:req, tmp:req, cond
__adldst_l str, \src, \sym, \tmp, \cond
.endm
.macro __ldst_va, op, reg, tmp, sym, cond, offset
#if __LINUX_ARM_ARCH__ >= 7 || \
!defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
mov_l \tmp, \sym, \cond
#else
/*
* Avoid a literal load, by emitting a sequence of ADD/LDR instructions
* with the appropriate relocations. The combined sequence has a range
* of -/+ 256 MiB, which should be sufficient for the core kernel and
* for modules loaded into the module region.
*/
.globl \sym
.reloc .L0_\@, R_ARM_ALU_PC_G0_NC, \sym
.reloc .L1_\@, R_ARM_ALU_PC_G1_NC, \sym
.reloc .L2_\@, R_ARM_LDR_PC_G2, \sym
.L0_\@: sub\cond \tmp, pc, #8 - \offset
.L1_\@: sub\cond \tmp, \tmp, #4 - \offset
.L2_\@:
#endif
\op\cond \reg, [\tmp, #\offset]
.endm
/*
* ldr_va - load a 32-bit word from the virtual address of \sym
*/
.macro ldr_va, rd:req, sym:req, cond, tmp, offset=0
.ifnb \tmp
__ldst_va ldr, \rd, \tmp, \sym, \cond, \offset
.else
__ldst_va ldr, \rd, \rd, \sym, \cond, \offset
.endif
.endm
/*
* str_va - store a 32-bit word to the virtual address of \sym
*/
.macro str_va, rn:req, sym:req, tmp:req, cond
__ldst_va str, \rn, \tmp, \sym, \cond, 0
.endm
/*
* ldr_this_cpu_armv6 - Load a 32-bit word from the per-CPU variable 'sym',
* without using a temp register. Supported in ARM mode
* only.
*/
.macro ldr_this_cpu_armv6, rd:req, sym:req
this_cpu_offset \rd
.globl \sym
.reloc .L0_\@, R_ARM_ALU_PC_G0_NC, \sym
.reloc .L1_\@, R_ARM_ALU_PC_G1_NC, \sym
.reloc .L2_\@, R_ARM_LDR_PC_G2, \sym
add \rd, \rd, pc
.L0_\@: sub \rd, \rd, #4
.L1_\@: sub \rd, \rd, #0
.L2_\@: ldr \rd, [\rd, #4]
.endm
/*
* ldr_this_cpu - Load a 32-bit word from the per-CPU variable 'sym'
* into register 'rd', which may be the stack pointer,
* using 't1' and 't2' as general temp registers. These
* are permitted to overlap with 'rd' if != sp
*/
.macro ldr_this_cpu, rd:req, sym:req, t1:req, t2:req
#ifndef CONFIG_SMP
ldr_va \rd, \sym, tmp=\t1
#elif __LINUX_ARM_ARCH__ >= 7 || \
!defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
this_cpu_offset \t1
mov_l \t2, \sym
ldr \rd, [\t1, \t2]
#else
ldr_this_cpu_armv6 \rd, \sym
#endif
.endm
/*
* rev_l - byte-swap a 32-bit value
*
* @val: source/destination register
* @tmp: scratch register
*/
.macro rev_l, val:req, tmp:req
.if __LINUX_ARM_ARCH__ < 6
eor \tmp, \val, \val, ror #16
bic \tmp, \tmp, #0x00ff0000
mov \val, \val, ror #8
eor \val, \val, \tmp, lsr #8
.else
rev \val, \val
.endif
.endm
.if __LINUX_ARM_ARCH__ < 6
.set .Lrev_l_uses_tmp, 1
.else
.set .Lrev_l_uses_tmp, 0
.endif
/*
* bl_r - branch and link to register
*
* @dst: target to branch to
* @c: conditional opcode suffix
*/
.macro bl_r, dst:req, c
.if __LINUX_ARM_ARCH__ < 6
mov\c lr, pc
mov\c pc, \dst
.else
blx\c \dst
.endif
.endm
#endif /* __ASM_ASSEMBLER_H__ */