Commit b1d70c62 authored by Michal Simek's avatar Michal Simek
Browse files

microblaze: Simplify entry.S - save/restore r3/r4 - ret_from_trap 



There is possible to save r3/r4 at the beggining of user part
before calling handlers and at the end restore it.

Signed-off-by: default avatarMichal Simek <monstr@monstr.eu>
parent 79bf3a13

arch/microblaze/kernel/entry.S

+30 −48
Original line number Diff line number Diff line
@@ -305,7 +305,7 @@ C_ENTRY(_user_exception): 
	swi	r11, r1, PTO+PT_R1;		/* Store user SP.  */

	addi	r11, r0, 1;

	swi	r11, r0, TOPHYS(PER_CPU(KM));	/* Now we're in kernel-mode.  */

2:	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE));	/* get saved current */

2:	lwi	CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));

	/* Save away the syscall number.  */

	swi	r12, r1, PTO+PT_R0;

	tovirt(r1,r1)
@@ -322,8 +322,7 @@ C_ENTRY(_user_exception): 
	rtid	r11, 0

	nop

3:

	add	r11, r0, CURRENT_TASK	 /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO /* get thread info */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO /* get thread info */

	lwi	r11, r11, TI_FLAGS	 /* get flags in thread info */

	andi	r11, r11, _TIF_WORK_SYSCALL_MASK

	beqi	r11, 4f
@@ -382,58 +381,50 @@ C_ENTRY(ret_from_trap): 
/* See if returning to kernel mode, if so, skip resched &c.  */

	bnei	r11, 2f;



	swi	r3, r1, PTO + PT_R3

	swi	r4, r1, PTO + PT_R4



	/* We're returning to user mode, so check for various conditions that

	 * trigger rescheduling. */

	# FIXME: Restructure all these flag checks.

	add	r11, r0, CURRENT_TASK;	/* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

	/* FIXME: Restructure all these flag checks. */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, r11, TI_FLAGS;		/* get flags in thread info */

	andi	r11, r11, _TIF_WORK_SYSCALL_MASK

	beqi	r11, 1f



	swi	r3, r1, PTO + PT_R3

	swi	r4, r1, PTO + PT_R4

	brlid	r15, do_syscall_trace_leave

	addik	r5, r1, PTO + PT_R0

	lwi	r3, r1, PTO + PT_R3

	lwi	r4, r1, PTO + PT_R4

1:



	/* We're returning to user mode, so check for various conditions that

	 * trigger rescheduling. */

	/* Get current task ptr into r11 */

	add	r11, r0, CURRENT_TASK;	/* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

	/* get thread info from current task */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;

	lwi	r11, r11, TI_FLAGS;		/* get flags in thread info */

	andi	r11, r11, _TIF_NEED_RESCHED;

	beqi	r11, 5f;



	swi	r3, r1, PTO + PT_R3; /* store syscall result */

	swi	r4, r1, PTO + PT_R4;

	bralid	r15, schedule;	/* Call scheduler */

	nop;				/* delay slot */

	lwi	r3, r1, PTO + PT_R3; /* restore syscall result */

	lwi	r4, r1, PTO + PT_R4;



	/* Maybe handle a signal */

5:	add	r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

5:	/* get thread info from current task*/

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;

	lwi	r11, r11, TI_FLAGS;	/* get flags in thread info */

	andi	r11, r11, _TIF_SIGPENDING;

	beqi	r11, 1f;		/* Signals to handle, handle them */



	swi	r3, r1, PTO + PT_R3; /* store syscall result */

	swi	r4, r1, PTO + PT_R4;

	la	r5, r1, PTO;		/* Arg 1: struct pt_regs *regs */

	add	r6, r0, r0;		/* Arg 2: sigset_t *oldset */

	addi	r7, r0, 1;		/* Arg 3: int in_syscall */

	bralid	r15, do_signal;	/* Handle any signals */

	nop;



/* Finally, return to user state.  */

1:

	lwi	r3, r1, PTO + PT_R3; /* restore syscall result */

	lwi	r4, r1, PTO + PT_R4;



/* Finally, return to user state.  */

1:	swi	r0, r0, PER_CPU(KM);	/* Now officially in user state. */

	swi	r0, r0, PER_CPU(KM);	/* Now officially in user state. */

	add	r11, r0, CURRENT_TASK;	/* Get current task ptr into r11 */

	swi	r11, r0, PER_CPU(CURRENT_SAVE); /* save current */

	VM_OFF;
@@ -565,7 +556,7 @@ C_ENTRY(sys_rt_sigreturn_wrapper): 
	swi	r11, r1, PTO+PT_R1; /* Store user SP.  */		\

	addi	r11, r0, 1;						\

	swi	r11, r0, TOPHYS(PER_CPU(KM)); /* Now we're in kernel-mode.*/\

2:	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */\

2:	lwi	CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));	\

	/* Save away the syscall number.  */				\

	swi	r0, r1, PTO+PT_R0;					\

	tovirt(r1,r1)
@@ -673,9 +664,7 @@ C_ENTRY(ret_from_exc): 


	/* We're returning to user mode, so check for various conditions that

	   trigger rescheduling. */

	/* Get current task ptr into r11 */

	add	r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, r11, TI_FLAGS;	/* get flags in thread info */

	andi	r11, r11, _TIF_NEED_RESCHED;

	beqi	r11, 5f;
@@ -685,8 +674,7 @@ C_ENTRY(ret_from_exc): 
	nop;				/* delay slot */



	/* Maybe handle a signal */

5:	add	r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

5:	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, r11, TI_FLAGS;	/* get flags in thread info */

	andi	r11, r11, _TIF_SIGPENDING;

	beqi	r11, 1f;		/* Signals to handle, handle them */
@@ -802,7 +790,7 @@ C_ENTRY(_interrupt): 
	swi	r11, r0, TOPHYS(PER_CPU(KM));



2:

	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE));

	lwi	CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));

	swi	r0, r1, PTO + PT_R0;

	tovirt(r1,r1)

	la	r5, r1, PTO;
@@ -817,8 +805,7 @@ ret_from_irq: 
	lwi	r11, r1, PTO + PT_MODE;

	bnei	r11, 2f;



	add	r11, r0, CURRENT_TASK;

	lwi	r11, r11, TS_THREAD_INFO;

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;

	lwi	r11, r11, TI_FLAGS; /* MS: get flags from thread info */

	andi	r11, r11, _TIF_NEED_RESCHED;

	beqi	r11, 5f
@@ -826,8 +813,7 @@ ret_from_irq: 
	nop; /* delay slot */



    /* Maybe handle a signal */

5:	add	r11, r0, CURRENT_TASK;

	lwi	r11, r11, TS_THREAD_INFO; /* MS: get thread info */

5:	lwi	r11, CURRENT_TASK, TS_THREAD_INFO; /* MS: get thread info */

	lwi	r11, r11, TI_FLAGS; /* get flags in thread info */

	andi	r11, r11, _TIF_SIGPENDING;

	beqid	r11, no_intr_resched
@@ -855,8 +841,7 @@ no_intr_resched: 
/* MS: Return to kernel state. */

2:

#ifdef CONFIG_PREEMPT

	add	r11, r0, CURRENT_TASK;

	lwi	r11, r11, TS_THREAD_INFO;

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;

	/* MS: get preempt_count from thread info */

	lwi	r5, r11, TI_PREEMPT_COUNT;

	bgti	r5, restore;
@@ -869,8 +854,7 @@ preempt: 
	/* interrupts are off that's why I am calling preempt_chedule_irq */

	bralid	r15, preempt_schedule_irq

	nop

	add	r11, r0, CURRENT_TASK;	/* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r5, r11, TI_FLAGS;		/* get flags in thread info */

	andi	r5, r5, _TIF_NEED_RESCHED;

	bnei	r5, preempt /* if non zero jump to resched */
@@ -938,7 +922,7 @@ C_ENTRY(_debug_exception): 
	swi	r11, r1, PTO+PT_R1; /* Store user SP.  */

	addi	r11, r0, 1;

	swi	r11, r0, TOPHYS(PER_CPU(KM));	/* Now we're in kernel-mode.  */

2:	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)); /* get saved current */

2:	lwi	CURRENT_TASK, r0, TOPHYS(PER_CPU(CURRENT_SAVE));

	/* Save away the syscall number.  */

	swi	r0, r1, PTO+PT_R0;

	tovirt(r1,r1)
@@ -958,8 +942,7 @@ dbtrap_call: rtbd r11, 0; 
	bnei	r11, 2f;



	/* Get current task ptr into r11 */

	add	r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, r11, TI_FLAGS;	/* get flags in thread info */

	andi	r11, r11, _TIF_NEED_RESCHED;

	beqi	r11, 5f;
@@ -972,8 +955,7 @@ dbtrap_call: rtbd r11, 0; 
	/* XXX m68knommu also checks TASK_STATE & TASK_COUNTER here.  */



	/* Maybe handle a signal */

5:	add	r11, r0, CURRENT_TASK; /* Get current task ptr into r11 */

	lwi	r11, r11, TS_THREAD_INFO;	/* get thread info */

5:	lwi	r11, CURRENT_TASK, TS_THREAD_INFO;	/* get thread info */

	lwi	r11, r11, TI_FLAGS;	/* get flags in thread info */

	andi	r11, r11, _TIF_SIGPENDING;

	beqi	r11, 1f;		/* Signals to handle, handle them */
@@ -1030,7 +1012,7 @@ DBTRAP_return: /* Make global symbol for debugging */ 


ENTRY(_switch_to)

	/* prepare return value */

	addk	r3, r0, r31

	addk	r3, r0, CURRENT_TASK



	/* save registers in cpu_context */

	/* use r11 and r12, volatile registers, as temp register */
@@ -1074,10 +1056,10 @@ ENTRY(_switch_to) 
	nop

	swi	r12, r11, CC_FSR



	/* update r31, the current */

	lwi	r31, r6, TI_TASK/* give me pointer to task which will be next */

	/* update r31, the current-give me pointer to task which will be next */

	lwi	CURRENT_TASK, r6, TI_TASK

	/* stored it to current_save too */

	swi	r31, r0, PER_CPU(CURRENT_SAVE)

	swi	CURRENT_TASK, r0, PER_CPU(CURRENT_SAVE)



	/* get new process' cpu context and restore */

	/* give me start where start context of next task */