Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
Yoshinori Sato | df2078b | 2015-05-11 02:32:13 +0900 | [diff] [blame] | 2 | /* |
| 3 | * |
| 4 | * linux/arch/h8300/kernel/entry.S |
| 5 | * |
| 6 | * Yoshinori Sato <ysato@users.sourceforge.jp> |
| 7 | * David McCullough <davidm@snapgear.com> |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * entry.S |
| 13 | * include exception/interrupt gateway |
| 14 | * system call entry |
| 15 | */ |
| 16 | |
| 17 | #include <linux/sys.h> |
| 18 | #include <asm/unistd.h> |
| 19 | #include <asm/setup.h> |
| 20 | #include <asm/segment.h> |
| 21 | #include <asm/linkage.h> |
| 22 | #include <asm/asm-offsets.h> |
| 23 | #include <asm/thread_info.h> |
| 24 | #include <asm/errno.h> |
| 25 | |
| 26 | #if defined(CONFIG_CPU_H8300H) |
| 27 | #define USERRET 8 |
| 28 | INTERRUPTS = 64 |
| 29 | .h8300h |
| 30 | .macro SHLL2 reg |
| 31 | shll.l \reg |
| 32 | shll.l \reg |
| 33 | .endm |
| 34 | .macro SHLR2 reg |
| 35 | shlr.l \reg |
| 36 | shlr.l \reg |
| 37 | .endm |
| 38 | .macro SAVEREGS |
| 39 | mov.l er0,@-sp |
| 40 | mov.l er1,@-sp |
| 41 | mov.l er2,@-sp |
| 42 | mov.l er3,@-sp |
| 43 | .endm |
| 44 | .macro RESTOREREGS |
| 45 | mov.l @sp+,er3 |
| 46 | mov.l @sp+,er2 |
| 47 | .endm |
| 48 | .macro SAVEEXR |
| 49 | .endm |
| 50 | .macro RESTOREEXR |
| 51 | .endm |
| 52 | #endif |
| 53 | #if defined(CONFIG_CPU_H8S) |
| 54 | #define USERRET 10 |
| 55 | #define USEREXR 8 |
| 56 | INTERRUPTS = 128 |
| 57 | .h8300s |
| 58 | .macro SHLL2 reg |
| 59 | shll.l #2,\reg |
| 60 | .endm |
| 61 | .macro SHLR2 reg |
| 62 | shlr.l #2,\reg |
| 63 | .endm |
| 64 | .macro SAVEREGS |
| 65 | stm.l er0-er3,@-sp |
| 66 | .endm |
| 67 | .macro RESTOREREGS |
| 68 | ldm.l @sp+,er2-er3 |
| 69 | .endm |
| 70 | .macro SAVEEXR |
| 71 | mov.w @(USEREXR:16,er0),r1 |
| 72 | mov.w r1,@(LEXR-LER3:16,sp) /* copy EXR */ |
| 73 | .endm |
| 74 | .macro RESTOREEXR |
| 75 | mov.w @(LEXR-LER1:16,sp),r1 /* restore EXR */ |
| 76 | mov.b r1l,r1h |
| 77 | mov.w r1,@(USEREXR:16,er0) |
| 78 | .endm |
| 79 | #endif |
| 80 | |
| 81 | |
| 82 | /* CPU context save/restore macros. */ |
| 83 | |
| 84 | .macro SAVE_ALL |
| 85 | mov.l er0,@-sp |
| 86 | stc ccr,r0l /* check kernel mode */ |
| 87 | btst #4,r0l |
| 88 | bne 5f |
| 89 | |
| 90 | /* user mode */ |
| 91 | mov.l sp,@_sw_usp |
| 92 | mov.l @sp,er0 /* restore saved er0 */ |
| 93 | orc #0x10,ccr /* switch kernel stack */ |
| 94 | mov.l @_sw_ksp,sp |
| 95 | sub.l #(LRET-LORIG),sp /* allocate LORIG - LRET */ |
| 96 | SAVEREGS |
| 97 | mov.l @_sw_usp,er0 |
| 98 | mov.l @(USERRET:16,er0),er1 /* copy the RET addr */ |
| 99 | mov.l er1,@(LRET-LER3:16,sp) |
| 100 | SAVEEXR |
| 101 | |
| 102 | mov.l @(LORIG-LER3:16,sp),er0 |
| 103 | mov.l er0,@(LER0-LER3:16,sp) /* copy ER0 */ |
| 104 | mov.w e1,r1 /* e1 highbyte = ccr */ |
| 105 | and #0xef,r1h /* mask mode? flag */ |
| 106 | bra 6f |
| 107 | 5: |
| 108 | /* kernel mode */ |
| 109 | mov.l @sp,er0 /* restore saved er0 */ |
| 110 | subs #2,sp /* set dummy ccr */ |
| 111 | subs #4,sp /* set dummp sp */ |
| 112 | SAVEREGS |
| 113 | mov.w @(LRET-LER3:16,sp),r1 /* copy old ccr */ |
| 114 | 6: |
| 115 | mov.b r1h,r1l |
| 116 | mov.b #0,r1h |
| 117 | mov.w r1,@(LCCR-LER3:16,sp) /* set ccr */ |
| 118 | mov.l @_sw_usp,er2 |
| 119 | mov.l er2,@(LSP-LER3:16,sp) /* set usp */ |
| 120 | mov.l er6,@-sp /* syscall arg #6 */ |
| 121 | mov.l er5,@-sp /* syscall arg #5 */ |
| 122 | mov.l er4,@-sp /* syscall arg #4 */ |
| 123 | .endm /* r1 = ccr */ |
| 124 | |
| 125 | .macro RESTORE_ALL |
| 126 | mov.l @sp+,er4 |
| 127 | mov.l @sp+,er5 |
| 128 | mov.l @sp+,er6 |
| 129 | RESTOREREGS |
| 130 | mov.w @(LCCR-LER1:16,sp),r0 /* check kernel mode */ |
| 131 | btst #4,r0l |
| 132 | bne 7f |
| 133 | |
| 134 | orc #0xc0,ccr |
| 135 | mov.l @(LSP-LER1:16,sp),er0 |
| 136 | mov.l @(LER0-LER1:16,sp),er1 /* restore ER0 */ |
| 137 | mov.l er1,@er0 |
| 138 | RESTOREEXR |
| 139 | mov.w @(LCCR-LER1:16,sp),r1 /* restore the RET addr */ |
| 140 | mov.b r1l,r1h |
| 141 | mov.b @(LRET+1-LER1:16,sp),r1l |
| 142 | mov.w r1,e1 |
| 143 | mov.w @(LRET+2-LER1:16,sp),r1 |
| 144 | mov.l er1,@(USERRET:16,er0) |
| 145 | |
| 146 | mov.l @sp+,er1 |
| 147 | add.l #(LRET-LER1),sp /* remove LORIG - LRET */ |
| 148 | mov.l sp,@_sw_ksp |
| 149 | andc #0xef,ccr /* switch to user mode */ |
| 150 | mov.l er0,sp |
| 151 | bra 8f |
| 152 | 7: |
| 153 | mov.l @sp+,er1 |
| 154 | add.l #10,sp |
| 155 | 8: |
| 156 | mov.l @sp+,er0 |
| 157 | adds #4,sp /* remove the sw created LVEC */ |
| 158 | rte |
| 159 | .endm |
| 160 | |
| 161 | .globl _system_call |
| 162 | .globl ret_from_exception |
| 163 | .globl ret_from_fork |
| 164 | .globl ret_from_kernel_thread |
| 165 | .globl ret_from_interrupt |
| 166 | .globl _interrupt_redirect_table |
| 167 | .globl _sw_ksp,_sw_usp |
| 168 | .globl _resume |
| 169 | .globl _interrupt_entry |
| 170 | .globl _trace_break |
| 171 | .globl _nmi |
| 172 | |
| 173 | #if defined(CONFIG_ROMKERNEL) |
| 174 | .section .int_redirect,"ax" |
| 175 | _interrupt_redirect_table: |
| 176 | #if defined(CONFIG_CPU_H8300H) |
| 177 | .rept 7 |
| 178 | .long 0 |
| 179 | .endr |
| 180 | #endif |
| 181 | #if defined(CONFIG_CPU_H8S) |
| 182 | .rept 5 |
| 183 | .long 0 |
| 184 | .endr |
| 185 | jmp @_trace_break |
| 186 | .long 0 |
| 187 | #endif |
| 188 | |
| 189 | jsr @_interrupt_entry /* NMI */ |
| 190 | jmp @_system_call /* TRAPA #0 (System call) */ |
| 191 | .long 0 |
Yoshinori Sato | 96ff2d7 | 2016-01-20 23:27:30 +0900 | [diff] [blame] | 192 | #if defined(CONFIG_KGDB) |
| 193 | jmp @_kgdb_trap |
| 194 | #else |
Yoshinori Sato | df2078b | 2015-05-11 02:32:13 +0900 | [diff] [blame] | 195 | .long 0 |
Yoshinori Sato | 96ff2d7 | 2016-01-20 23:27:30 +0900 | [diff] [blame] | 196 | #endif |
Yoshinori Sato | df2078b | 2015-05-11 02:32:13 +0900 | [diff] [blame] | 197 | jmp @_trace_break /* TRAPA #3 (breakpoint) */ |
| 198 | .rept INTERRUPTS-12 |
| 199 | jsr @_interrupt_entry |
| 200 | .endr |
| 201 | #endif |
| 202 | #if defined(CONFIG_RAMKERNEL) |
| 203 | .globl _interrupt_redirect_table |
| 204 | .section .bss |
| 205 | _interrupt_redirect_table: |
| 206 | .space 4 |
| 207 | #endif |
| 208 | |
| 209 | .section .text |
| 210 | .align 2 |
| 211 | _interrupt_entry: |
| 212 | SAVE_ALL |
| 213 | /* r1l is saved ccr */ |
| 214 | mov.l sp,er0 |
| 215 | add.l #LVEC,er0 |
| 216 | btst #4,r1l |
| 217 | bne 1f |
| 218 | /* user LVEC */ |
| 219 | mov.l @_sw_usp,er0 |
| 220 | adds #4,er0 |
| 221 | 1: |
| 222 | mov.l @er0,er0 /* LVEC address */ |
| 223 | #if defined(CONFIG_ROMKERNEL) |
| 224 | sub.l #_interrupt_redirect_table,er0 |
| 225 | #endif |
| 226 | #if defined(CONFIG_RAMKERNEL) |
| 227 | mov.l @_interrupt_redirect_table,er1 |
| 228 | sub.l er1,er0 |
| 229 | #endif |
| 230 | SHLR2 er0 |
| 231 | dec.l #1,er0 |
| 232 | mov.l sp,er1 |
| 233 | subs #4,er1 /* adjust ret_pc */ |
| 234 | #if defined(CONFIG_CPU_H8S) |
| 235 | orc #7,exr |
| 236 | #endif |
| 237 | jsr @do_IRQ |
| 238 | jmp @ret_from_interrupt |
| 239 | |
| 240 | _system_call: |
| 241 | subs #4,sp /* dummy LVEC */ |
| 242 | SAVE_ALL |
| 243 | /* er0: syscall nr */ |
| 244 | andc #0xbf,ccr |
| 245 | mov.l er0,er4 |
| 246 | |
| 247 | /* save top of frame */ |
| 248 | mov.l sp,er0 |
| 249 | jsr @set_esp0 |
Yoshinori Sato | 2f1b007 | 2016-01-15 23:51:51 +0900 | [diff] [blame] | 250 | andc #0x3f,ccr |
Yoshinori Sato | df2078b | 2015-05-11 02:32:13 +0900 | [diff] [blame] | 251 | mov.l sp,er2 |
| 252 | and.w #0xe000,r2 |
| 253 | mov.l @(TI_FLAGS:16,er2),er2 |
| 254 | and.w #_TIF_WORK_SYSCALL_MASK,r2 |
| 255 | beq 1f |
| 256 | mov.l sp,er0 |
| 257 | jsr @do_syscall_trace_enter |
| 258 | 1: |
| 259 | cmp.l #__NR_syscalls,er4 |
| 260 | bcc badsys |
| 261 | SHLL2 er4 |
| 262 | mov.l #_sys_call_table,er0 |
| 263 | add.l er4,er0 |
| 264 | mov.l @er0,er4 |
| 265 | beq ret_from_exception:16 |
| 266 | mov.l @(LER1:16,sp),er0 |
| 267 | mov.l @(LER2:16,sp),er1 |
| 268 | mov.l @(LER3:16,sp),er2 |
| 269 | jsr @er4 |
| 270 | mov.l er0,@(LER0:16,sp) /* save the return value */ |
| 271 | mov.l sp,er2 |
| 272 | and.w #0xe000,r2 |
| 273 | mov.l @(TI_FLAGS:16,er2),er2 |
| 274 | and.w #_TIF_WORK_SYSCALL_MASK,r2 |
| 275 | beq 2f |
| 276 | mov.l sp,er0 |
| 277 | jsr @do_syscall_trace_leave |
| 278 | 2: |
| 279 | orc #0xc0,ccr |
| 280 | bra resume_userspace |
| 281 | |
| 282 | badsys: |
| 283 | mov.l #-ENOSYS,er0 |
| 284 | mov.l er0,@(LER0:16,sp) |
| 285 | bra resume_userspace |
| 286 | |
| 287 | #if !defined(CONFIG_PREEMPT) |
| 288 | #define resume_kernel restore_all |
| 289 | #endif |
| 290 | |
| 291 | ret_from_exception: |
| 292 | #if defined(CONFIG_PREEMPT) |
| 293 | orc #0xc0,ccr |
| 294 | #endif |
| 295 | ret_from_interrupt: |
| 296 | mov.b @(LCCR+1:16,sp),r0l |
| 297 | btst #4,r0l |
| 298 | bne resume_kernel:16 /* return from kernel */ |
| 299 | resume_userspace: |
| 300 | andc #0xbf,ccr |
| 301 | mov.l sp,er4 |
| 302 | and.w #0xe000,r4 /* er4 <- current thread info */ |
| 303 | mov.l @(TI_FLAGS:16,er4),er1 |
| 304 | and.l #_TIF_WORK_MASK,er1 |
| 305 | beq restore_all:8 |
| 306 | work_pending: |
| 307 | btst #TIF_NEED_RESCHED,r1l |
| 308 | bne work_resched:8 |
| 309 | /* work notifysig */ |
| 310 | mov.l sp,er0 |
| 311 | subs #4,er0 /* er0: pt_regs */ |
| 312 | jsr @do_notify_resume |
| 313 | bra resume_userspace:8 |
| 314 | work_resched: |
| 315 | mov.l sp,er0 |
| 316 | jsr @set_esp0 |
| 317 | jsr @schedule |
| 318 | bra resume_userspace:8 |
| 319 | restore_all: |
| 320 | RESTORE_ALL /* Does RTE */ |
| 321 | |
| 322 | #if defined(CONFIG_PREEMPT) |
| 323 | resume_kernel: |
| 324 | mov.l @(TI_PRE_COUNT:16,er4),er0 |
| 325 | bne restore_all:8 |
| 326 | need_resched: |
| 327 | mov.l @(TI_FLAGS:16,er4),er0 |
| 328 | btst #TIF_NEED_RESCHED,r0l |
| 329 | beq restore_all:8 |
| 330 | mov.b @(LCCR+1:16,sp),r0l /* Interrupt Enabled? */ |
| 331 | bmi restore_all:8 |
| 332 | mov.l sp,er0 |
| 333 | jsr @set_esp0 |
| 334 | jsr @preempt_schedule_irq |
| 335 | bra need_resched:8 |
| 336 | #endif |
| 337 | |
| 338 | ret_from_fork: |
| 339 | mov.l er2,er0 |
| 340 | jsr @schedule_tail |
| 341 | jmp @ret_from_exception |
| 342 | |
| 343 | ret_from_kernel_thread: |
| 344 | mov.l er2,er0 |
| 345 | jsr @schedule_tail |
| 346 | mov.l @(LER4:16,sp),er0 |
| 347 | mov.l @(LER5:16,sp),er1 |
| 348 | jsr @er1 |
| 349 | jmp @ret_from_exception |
| 350 | |
| 351 | _resume: |
| 352 | /* |
| 353 | * Beware - when entering resume, offset of tss is in d1, |
| 354 | * prev (the current task) is in a0, next (the new task) |
| 355 | * is in a1 and d2.b is non-zero if the mm structure is |
| 356 | * shared between the tasks, so don't change these |
| 357 | * registers until their contents are no longer needed. |
| 358 | */ |
| 359 | |
| 360 | /* save sr */ |
| 361 | sub.w r3,r3 |
| 362 | stc ccr,r3l |
| 363 | mov.w r3,@(THREAD_CCR+2:16,er0) |
| 364 | |
| 365 | /* disable interrupts */ |
| 366 | orc #0xc0,ccr |
| 367 | mov.l @_sw_usp,er3 |
| 368 | mov.l er3,@(THREAD_USP:16,er0) |
| 369 | mov.l sp,@(THREAD_KSP:16,er0) |
| 370 | |
| 371 | /* Skip address space switching if they are the same. */ |
| 372 | /* FIXME: what did we hack out of here, this does nothing! */ |
| 373 | |
| 374 | mov.l @(THREAD_USP:16,er1),er0 |
| 375 | mov.l er0,@_sw_usp |
| 376 | mov.l @(THREAD_KSP:16,er1),sp |
| 377 | |
| 378 | /* restore status register */ |
| 379 | mov.w @(THREAD_CCR+2:16,er1),r3 |
| 380 | |
| 381 | ldc r3l,ccr |
| 382 | rts |
| 383 | |
| 384 | _trace_break: |
| 385 | subs #4,sp |
| 386 | SAVE_ALL |
| 387 | sub.l er1,er1 |
| 388 | dec.l #1,er1 |
| 389 | mov.l er1,@(LORIG,sp) |
| 390 | mov.l sp,er0 |
| 391 | jsr @set_esp0 |
| 392 | mov.l @_sw_usp,er0 |
| 393 | mov.l @er0,er1 |
| 394 | mov.w @(-2:16,er1),r2 |
| 395 | cmp.w #0x5730,r2 |
| 396 | beq 1f |
| 397 | subs #2,er1 |
| 398 | mov.l er1,@er0 |
| 399 | 1: |
| 400 | and.w #0xff,e1 |
| 401 | mov.l er1,er0 |
| 402 | jsr @trace_trap |
| 403 | jmp @ret_from_exception |
| 404 | |
| 405 | _nmi: |
| 406 | subs #4, sp |
| 407 | mov.l er0, @-sp |
| 408 | mov.l @_interrupt_redirect_table, er0 |
| 409 | add.l #8*4, er0 |
| 410 | mov.l er0, @(4,sp) |
| 411 | mov.l @sp+, er0 |
| 412 | jmp @_interrupt_entry |
| 413 | |
Yoshinori Sato | 96ff2d7 | 2016-01-20 23:27:30 +0900 | [diff] [blame] | 414 | #if defined(CONFIG_KGDB) |
| 415 | _kgdb_trap: |
| 416 | subs #4,sp |
| 417 | SAVE_ALL |
| 418 | mov.l sp,er0 |
| 419 | add.l #LRET,er0 |
| 420 | mov.l er0,@(LSP,sp) |
| 421 | jsr @set_esp0 |
| 422 | mov.l sp,er0 |
| 423 | subs #4,er0 |
| 424 | jsr @h8300_kgdb_trap |
| 425 | jmp @ret_from_exception |
| 426 | #endif |
| 427 | |
Yoshinori Sato | df2078b | 2015-05-11 02:32:13 +0900 | [diff] [blame] | 428 | .section .bss |
| 429 | _sw_ksp: |
| 430 | .space 4 |
| 431 | _sw_usp: |
| 432 | .space 4 |
| 433 | |
| 434 | .end |