microblaze/kernel/entry.S

2  * Low-level system-call handling, trap handlers and context-switching
4  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
5  * Copyright (C) 2008-2009 PetaLogix
25 #include <asm/asm-offsets.h>
160 /* Define how to call high-level functions. With MMU, virtual mode must be
161  * enabled when calling the high-level function. Clobbers R11.
175 	rted	r0, TOPHYS(1f);	\
177 1:
262 	bnei	r1, 1f;						\
263 	/* Kernel-mode state save.  */					\
264 	/* Reload kernel stack-ptr. */					\
268 	/* addik	r1, r1, -PT_SIZE; */				\
269 	addik	r1, r1, CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE; \
273 1:	/* User-mode state save.  */					\
280 	/* addik	r1, r1, -PT_SIZE; */			\
281 	addik r1, r1, THREAD_SIZE + CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE; \
285 	swi	r0, r1, PT_MODE; /* Was in user-mode.  */		\
295 	addik	r1, r1, -PT_SIZE
302 1:
304 	bgtid	r9, 1b
313 	addik	r1, r1, -PT_SIZE
320 1:
322 	bgtid	r9, 1b
336  * Syscall number in r12, args in r5-r10
353 	addik	r1, r1, -PT_SIZE; /* Make room on the stack.  */
358 	swi	r0, r1, PT_MODE;			/* Was in user-mode. */
367 /* where the trap should return need -8 to adjust for rtsd r15, 8*/
371  * the called function should return.  [note that MAKE_SYS_CALL uses label 1] */
382 	addik	r3, r0, -ENOSYS
399  * should return.  [note that MAKE_SYS_CALL uses label 1] */
402 	addi	r11, r12, -__NR_syscalls;
406 	add	r12, r12, r12;			/* convert num -> ptr */
408 	addi	r30, r0, 1			/* restarts allowed */
414 	addi	r3, r3, 1
417 	addi	r3, r3, 1
423 	/* where the trap should return need -8 to adjust for rtsd r15, 8 */
424 	addi	r15, r0, ret_from_trap-8
430 	addi	r3, r0, -ENOSYS;
433 /* We re-enable BIP bit before state restore */
447 	beqi	r11, 1f
451 1:
462 	bri	1b
469 	addik	r5, r1, 0;		/* Arg 1: struct pt_regs *regs */
473 	bri	1b
482 	lwi	r1, r1, PT_R1 - PT_SIZE;/* Restore user stack pointer. */
515 	addk	r5, r0, r19	/* ... and argument - in r19 */
522 	addik	r5, r1, 0;		/* add user context as 1st arg */
530 	addik	r17, r17, -4
532 	/* PC, before IRQ/trap - this is one instruction above */
537 	/* where the trap should return need -8 to adjust for rtsd r15, 8 */
538 	addik	r15, r0, ret_from_exc - 8
568 	/* PC, before IRQ/trap - this is one instruction above */
571 	/* where the trap should return need -8 to adjust for rtsd r15, 8 */
572 	addik	r15, r0, ret_from_exc-8
595 /* data and intruction trap - which is choose is resolved int fault.c */
598 	/* PC, before IRQ/trap - this is one instruction above */
601 	/* where the trap should return need -8 to adjust for rtsd r15, 8 */
602 	addik	r15, r0, ret_from_exc-8
610 	/* PC, before IRQ/trap - this is one instruction above */
613 	/* where the trap should return need -8 to adjust for rtsd r15, 8 */
614 	addik	r15, r0, ret_from_exc-8
628 1:
637 	bri	1b
647 	 * points (for instance, call-saved registers (because the normal
648 	 * C-compiler calling sequence in the kernel makes sure they're
649 	 * preserved), and call-clobbered registers in the case of
654 	addik	r5, r1, 0;		/* Arg 1: struct pt_regs *regs */
657 	bri	1b
668 	lwi	r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer. */
690  * The stack-pointer (r1) should have already been saved to the memory
701 	bnei	r1, 1f
703 /* Kernel-mode state save. */
707 /* MS: Make room on the stack -> activation record */
708 	addik	r1, r1, -PT_SIZE;
711 	swi	r1, r1, PT_MODE; /* 0 - user mode, 1 - kernel mode */
712 1:
713 /* User-mode state save. */
721 	addik	r1, r1, -PT_SIZE;
740 1:
747 	bri	1b
753 	addik	r5, r1, 0; /* Arg 1: struct pt_regs *regs */
756 	bri	1b
767 	lwi	r1, r1, PT_R1 - PT_SIZE;
841 	addik	r3, r3, -1
846 	/* return from reset need -8 to adjust for rtsd r15, 8 */
847 	addik   r15, r0, ret_from_reset - 8
864  * injecting fault in one of the TMR Microblaze core.
873 	addik	r1, r1, -PT_SIZE - 36
884 	 * break handler, below code configures the tmr manager
920 	addik	r3, r3, -1
924 	/* return from break need -8 to adjust for rtsd r15, 8 */
925 	addik   r15, r0, ret_from_break - 8
930 	/* flush the d-cache */
935 	 * To make sure microblaze i-cache is in a proper state
936 	 * invalidate the i-cache.
943 	mbar	1
961 	bnei	r1, 1f
962 /* MS: Kernel-mode state save - kgdb */
963 	lwi	r1, r0, TOPHYS(PER_CPU(ENTRY_SP)); /* Reload kernel stack-ptr*/
966 	addik   r1, r1, CONFIG_KERNEL_BASE_ADDR - CONFIG_KERNEL_START - PT_SIZE;
982 	addik   r11, r1, CONFIG_KERNEL_START - CONFIG_KERNEL_BASE_ADDR + PT_SIZE;
984 	/* MS: r31 - current pointer isn't changed */
996 /* MS: User-mode state save - gdb */
997 1:	lwi	r1, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */
1003 	addik	r1, r1, -PT_SIZE; /* Make room on the stack.  */
1006 	swi	r0, r1, PT_MODE; /* Was in user-mode.  */
1022 /* MS: Return to user space - gdb */
1023 1:
1033 	bri	1b
1039 	addik	r5, r1, 0;		/* Arg 1: struct pt_regs *regs */
1042 	bri	1b
1051 	lwi	r1, r1, PT_R1 - PT_SIZE; /* Restore user stack pointer */
1056 /* MS: Return to kernel state - kgdb */
1089 	/* save non-volatile registers */
1112 	/* update r31, the current-give me pointer to task which will be next */
1121 	/* non-volatile registers */
1161 	addik	r1, r1, -PT_SIZE
1167 	mbar	1
1175 	mbar	1
1181 	rtbd    r0, 1f
1183 1:
1266 	 * For TMR Inject API which injects the error should
1268 	 * TMR Inject is programmed with address of 0x200 so that
1283 syscall_table_size=(.-sys_call_table)