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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __M68K_ENTRY_H
#define __M68K_ENTRY_H
#include <asm/setup.h>
#include <asm/page.h>
#ifdef __ASSEMBLY__
#include <asm/thread_info.h>
#endif
/*
* Stack layout in 'ret_from_exception':
*
* This allows access to the syscall arguments in registers d1-d5
*
* 0(sp) - d1
* 4(sp) - d2
* 8(sp) - d3
* C(sp) - d4
* 10(sp) - d5
* 14(sp) - a0
* 18(sp) - a1
* 1C(sp) - a2
* 20(sp) - d0
* 24(sp) - orig_d0
* 28(sp) - stack adjustment
* 2C(sp) - [ sr ] [ format & vector ]
* 2E(sp) - [ pc-hiword ] [ sr ]
* 30(sp) - [ pc-loword ] [ pc-hiword ]
* 32(sp) - [ format & vector ] [ pc-loword ]
* ^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^
* M68K COLDFIRE
*/
/* the following macro is used when enabling interrupts */
#if defined(MACH_ATARI_ONLY)
/* block out HSYNC = ipl 2 on the atari */
#define ALLOWINT (~0x500)
#else
/* portable version */
#define ALLOWINT (~0x700)
#endif /* machine compilation types */
#ifdef __ASSEMBLY__
/*
* This defines the normal kernel pt-regs layout.
*
* regs a3-a6 and d6-d7 are preserved by C code
* the kernel doesn't mess with usp unless it needs to
*/
#define SWITCH_STACK_SIZE (6*4+4) /* includes return address */
#ifdef CONFIG_COLDFIRE
#ifdef CONFIG_COLDFIRE_SW_A7
/*
* This is made a little more tricky on older ColdFires. There is no
* separate supervisor and user stack pointers. Need to artificially
* construct a usp in software... When doing this we need to disable
* interrupts, otherwise bad things will happen.
*/
.globl sw_usp
.globl sw_ksp
.macro SAVE_ALL_SYS
move #0x2700,%sr /* disable intrs */
btst #5,%sp@(2) /* from user? */
bnes 6f /* no, skip */
movel %sp,sw_usp /* save user sp */
addql #8,sw_usp /* remove exception */
movel sw_ksp,%sp /* kernel sp */
subql #8,%sp /* room for exception */
clrl %sp@- /* stkadj */
movel %d0,%sp@- /* orig d0 */
movel %d0,%sp@- /* d0 */
lea %sp@(-32),%sp /* space for 8 regs */
moveml %d1-%d5/%a0-%a2,%sp@
movel sw_usp,%a0 /* get usp */
movel %a0@-,%sp@(PT_OFF_PC) /* copy exception program counter */
movel %a0@-,%sp@(PT_OFF_FORMATVEC)/*copy exception format/vector/sr */
bra 7f
6:
clrl %sp@- /* stkadj */
movel %d0,%sp@- /* orig d0 */
movel %d0,%sp@- /* d0 */
lea %sp@(-32),%sp /* space for 8 regs */
moveml %d1-%d5/%a0-%a2,%sp@
7:
.endm
.macro SAVE_ALL_INT
SAVE_ALL_SYS
moveq #-1,%d0 /* not system call entry */
movel %d0,%sp@(PT_OFF_ORIG_D0)
.endm
.macro RESTORE_USER
move #0x2700,%sr /* disable intrs */
movel sw_usp,%a0 /* get usp */
movel %sp@(PT_OFF_PC),%a0@- /* copy exception program counter */
movel %sp@(PT_OFF_FORMATVEC),%a0@-/*copy exception format/vector/sr */
moveml %sp@,%d1-%d5/%a0-%a2
lea %sp@(32),%sp /* space for 8 regs */
movel %sp@+,%d0
addql #4,%sp /* orig d0 */
addl %sp@+,%sp /* stkadj */
addql #8,%sp /* remove exception */
movel %sp,sw_ksp /* save ksp */
subql #8,sw_usp /* set exception */
movel sw_usp,%sp /* restore usp */
rte
.endm
.macro RDUSP
movel sw_usp,%a3
.endm
.macro WRUSP
movel %a3,sw_usp
.endm
#else /* !CONFIG_COLDFIRE_SW_A7 */
/*
* Modern ColdFire parts have separate supervisor and user stack
* pointers. Simple load and restore macros for this case.
*/
.macro SAVE_ALL_SYS
move #0x2700,%sr /* disable intrs */
clrl %sp@- /* stkadj */
movel %d0,%sp@- /* orig d0 */
movel %d0,%sp@- /* d0 */
lea %sp@(-32),%sp /* space for 8 regs */
moveml %d1-%d5/%a0-%a2,%sp@
.endm
.macro SAVE_ALL_INT
move #0x2700,%sr /* disable intrs */
clrl %sp@- /* stkadj */
pea -1:w /* orig d0 */
movel %d0,%sp@- /* d0 */
lea %sp@(-32),%sp /* space for 8 regs */
moveml %d1-%d5/%a0-%a2,%sp@
.endm
.macro RESTORE_USER
moveml %sp@,%d1-%d5/%a0-%a2
lea %sp@(32),%sp /* space for 8 regs */
movel %sp@+,%d0
addql #4,%sp /* orig d0 */
addl %sp@+,%sp /* stkadj */
rte
.endm
.macro RDUSP
/*move %usp,%a3*/
.word 0x4e6b
.endm
.macro WRUSP
/*move %a3,%usp*/
.word 0x4e63
.endm
#endif /* !CONFIG_COLDFIRE_SW_A7 */
.macro SAVE_SWITCH_STACK
lea %sp@(-24),%sp /* 6 regs */
moveml %a3-%a6/%d6-%d7,%sp@
.endm
.macro RESTORE_SWITCH_STACK
moveml %sp@,%a3-%a6/%d6-%d7
lea %sp@(24),%sp /* 6 regs */
.endm
#else /* !CONFIG_COLDFIRE */
/*
* All other types of m68k parts (68000, 680x0, CPU32) have the same
* entry and exit code.
*/
/*
* a -1 in the orig_d0 field signifies
* that the stack frame is NOT for syscall
*/
.macro SAVE_ALL_INT
clrl %sp@- /* stk_adj */
pea -1:w /* orig d0 */
movel %d0,%sp@- /* d0 */
moveml %d1-%d5/%a0-%a2,%sp@-
.endm
.macro SAVE_ALL_SYS
clrl %sp@- /* stk_adj */
movel %d0,%sp@- /* orig d0 */
movel %d0,%sp@- /* d0 */
moveml %d1-%d5/%a0-%a2,%sp@-
.endm
.macro RESTORE_ALL
moveml %sp@+,%a0-%a2/%d1-%d5
movel %sp@+,%d0
addql #4,%sp /* orig d0 */
addl %sp@+,%sp /* stk adj */
rte
.endm
.macro SAVE_SWITCH_STACK
moveml %a3-%a6/%d6-%d7,%sp@-
.endm
.macro RESTORE_SWITCH_STACK
moveml %sp@+,%a3-%a6/%d6-%d7
.endm
#endif /* !CONFIG_COLDFIRE */
/*
* Register %a2 is reserved and set to current task on MMU enabled systems.
* Non-MMU systems do not reserve %a2 in this way, and this definition is
* not used for them.
*/
#ifdef CONFIG_MMU
#define curptr a2
#define GET_CURRENT(tmp) get_current tmp
.macro get_current reg=%d0
movel %sp,\reg
andl #-THREAD_SIZE,\reg
movel \reg,%curptr
movel %curptr@,%curptr
.endm
#else
#define GET_CURRENT(tmp)
#endif /* CONFIG_MMU */
#else /* C source */
#define STR(X) STR1(X)
#define STR1(X) #X
#define SAVE_ALL_INT \
"clrl %%sp@-;" /* stk_adj */ \
"pea -1:w;" /* orig d0 = -1 */ \
"movel %%d0,%%sp@-;" /* d0 */ \
"moveml %%d1-%%d5/%%a0-%%a2,%%sp@-"
#define GET_CURRENT(tmp) \
"movel %%sp,"#tmp"\n\t" \
"andw #-"STR(THREAD_SIZE)","#tmp"\n\t" \
"movel "#tmp",%%a2\n\t" \
"movel %%a2@,%%a2"
#endif
#endif /* __M68K_ENTRY_H */
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