/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  linux/arch/arm/kernel/debug.S
 *
 *  Copyright (C) 1994-1999 Russell King
 *
 *  32-bit debugging code
 */
#include <linux/linkage.h>
#include <asm/assembler.h>

                .text

/*
 * Some debugging routines (useful if you've got MM problems and
 * printk isn't working).  For DEBUGGING ONLY!!!  Do not leave
 * references to these in a production kernel!
 */

#if !defined(CONFIG_DEBUG_SEMIHOSTING)
#include CONFIG_DEBUG_LL_INCLUDE
#endif

#ifdef CONFIG_MMU
                .macro  addruart_current, rx, tmp1, tmp2
                addruart        \tmp1, \tmp2, \rx
                mrc             p15, 0, \rx, c1, c0
                tst             \rx, #1
                moveq           \rx, \tmp1
                movne           \rx, \tmp2
                .endm

#else /* !CONFIG_MMU */
                .macro  addruart_current, rx, tmp1, tmp2
                addruart        \rx, \tmp1, \tmp2
                .endm

#endif /* CONFIG_MMU */

/*
 * Useful debugging routines
 */
ENTRY(printhex8)
                mov     r1, #8
                b       printhex
ENDPROC(printhex8)

ENTRY(printhex4)
                mov     r1, #4
                b       printhex
ENDPROC(printhex4)

ENTRY(printhex2)
                mov     r1, #2
printhex:       adr     r2, hexbuf_rel
                ldr     r3, [r2]
                add     r2, r2, r3
                add     r3, r2, r1
                mov     r1, #0
                strb    r1, [r3]
1:              and     r1, r0, #15
                mov     r0, r0, lsr #4
                cmp     r1, #10
                addlt   r1, r1, #'0'
                addge   r1, r1, #'a' - 10
                strb    r1, [r3, #-1]!
                teq     r3, r2
                bne     1b
                mov     r0, r2
                b       printascii
ENDPROC(printhex2)

                .pushsection .bss
hexbuf_addr:    .space 16
                .popsection
                .align
hexbuf_rel:     .long   hexbuf_addr - .

                .ltorg

#ifndef CONFIG_DEBUG_SEMIHOSTING

ENTRY(printascii)
                addruart_current r3, r1, r2
1:              teq     r0, #0
                ldrbne  r1, [r0], #1
                teqne   r1, #0
                reteq   lr
2:              teq     r1, #'\n'
                bne     3f
                mov     r1, #'\r'
#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL
                waituartcts r2, r3
#endif
                waituarttxrdy r2, r3
                senduart r1, r3
                busyuart r2, r3
                mov     r1, #'\n'
3:
#ifdef CONFIG_DEBUG_UART_FLOW_CONTROL
                waituartcts r2, r3
#endif
                waituarttxrdy r2, r3
                senduart r1, r3
                busyuart r2, r3
                b       1b
ENDPROC(printascii)

ENTRY(printch)
                addruart_current r3, r1, r2
                mov     r1, r0
                mov     r0, #0
                b       2b
ENDPROC(printch)

#ifdef CONFIG_MMU
ENTRY(debug_ll_addr)
                addruart r2, r3, ip
                str     r2, [r0]
                str     r3, [r1]
                ret     lr
ENDPROC(debug_ll_addr)
#endif

#else

ENTRY(printascii)
                mov     r1, r0
                mov     r0, #0x04               @ SYS_WRITE0
        ARM(    svc     #0x123456       )
#ifdef CONFIG_CPU_V7M
        THUMB(  bkpt    #0xab           )
#else
        THUMB(  svc     #0xab           )
#endif
                ret     lr
ENDPROC(printascii)

ENTRY(printch)
                adr     r1, hexbuf_rel
                ldr     r2, [r1]
                add     r1, r1, r2
                strb    r0, [r1]
                mov     r0, #0x03               @ SYS_WRITEC
        ARM(    svc     #0x123456       )
#ifdef CONFIG_CPU_V7M
        THUMB(  bkpt    #0xab           )
#else
        THUMB(  svc     #0xab           )
#endif
                ret     lr
ENDPROC(printch)

ENTRY(debug_ll_addr)
                mov     r2, #0
                str     r2, [r0]
                str     r2, [r1]
                ret     lr
ENDPROC(debug_ll_addr)

#endif