/* 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 */