kernel-fxtec-pro1x/arch/blackfin/mach-common/interrupt.S
Barry Song 33ded95b1c Blackfin: initial preempt support while returning from interrupt
Signed-off-by: Barry Song <barry.song@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-10-22 03:48:55 -04:00

326 lines
7 KiB
ArmAsm

/*
* Interrupt Entries
*
* Copyright 2005-2009 Analog Devices Inc.
* D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>
* Kenneth Albanowski <kjahds@kjahds.com>
*
* Licensed under the GPL-2 or later.
*/
#include <asm/blackfin.h>
#include <mach/irq.h>
#include <linux/linkage.h>
#include <asm/entry.h>
#include <asm/asm-offsets.h>
#include <asm/trace.h>
#include <asm/traps.h>
#include <asm/thread_info.h>
#include <asm/context.S>
.extern _ret_from_exception
#ifdef CONFIG_I_ENTRY_L1
.section .l1.text
#else
.text
#endif
.align 4 /* just in case */
/* Common interrupt entry code. First we do CLI, then push
* RETI, to keep interrupts disabled, but to allow this state to be changed
* by local_bh_enable.
* R0 contains the interrupt number, while R1 may contain the value of IPEND,
* or garbage if IPEND won't be needed by the ISR. */
__common_int_entry:
[--sp] = fp;
[--sp] = usp;
[--sp] = i0;
[--sp] = i1;
[--sp] = i2;
[--sp] = i3;
[--sp] = m0;
[--sp] = m1;
[--sp] = m2;
[--sp] = m3;
[--sp] = l0;
[--sp] = l1;
[--sp] = l2;
[--sp] = l3;
[--sp] = b0;
[--sp] = b1;
[--sp] = b2;
[--sp] = b3;
[--sp] = a0.x;
[--sp] = a0.w;
[--sp] = a1.x;
[--sp] = a1.w;
[--sp] = LC0;
[--sp] = LC1;
[--sp] = LT0;
[--sp] = LT1;
[--sp] = LB0;
[--sp] = LB1;
[--sp] = ASTAT;
[--sp] = r0; /* Skip reserved */
[--sp] = RETS;
r2 = RETI;
[--sp] = r2;
[--sp] = RETX;
[--sp] = RETN;
[--sp] = RETE;
[--sp] = SEQSTAT;
[--sp] = r1; /* IPEND - R1 may or may not be set up before jumping here. */
/* Switch to other method of keeping interrupts disabled. */
#ifdef CONFIG_DEBUG_HWERR
r1 = 0x3f;
sti r1;
#else
cli r1;
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
[--sp] = r0;
sp += -12;
call _trace_hardirqs_off;
sp += 12;
r0 = [sp++];
#endif
[--sp] = RETI; /* orig_pc */
/* Clear all L registers. */
r1 = 0 (x);
l0 = r1;
l1 = r1;
l2 = r1;
l3 = r1;
#ifdef CONFIG_FRAME_POINTER
fp = 0;
#endif
ANOMALY_283_315_WORKAROUND(p5, r7)
r1 = sp;
SP += -12;
#ifdef CONFIG_IPIPE
call ___ipipe_grab_irq
SP += 12;
cc = r0 == 0;
if cc jump .Lcommon_restore_context;
#else /* CONFIG_IPIPE */
#ifdef CONFIG_PREEMPT
r7 = sp;
r4.l = lo(ALIGN_PAGE_MASK);
r4.h = hi(ALIGN_PAGE_MASK);
r7 = r7 & r4;
p5 = r7;
r7 = [p5 + TI_PREEMPT]; /* get preempt count */
r7 += 1; /* increment it */
[p5 + TI_PREEMPT] = r7;
#endif
pseudo_long_call _do_irq, p2;
#ifdef CONFIG_PREEMPT
r7 += -1;
[p5 + TI_PREEMPT] = r7; /* restore preempt count */
#endif
SP += 12;
#endif /* CONFIG_IPIPE */
pseudo_long_call _return_from_int, p2;
.Lcommon_restore_context:
RESTORE_CONTEXT
rti;
/* interrupt routine for ivhw - 5 */
ENTRY(_evt_ivhw)
/* In case a single action kicks off multiple memory transactions, (like
* a cache line fetch, - this can cause multiple hardware errors, let's
* catch them all. First - make sure all the actions are complete, and
* the core sees the hardware errors.
*/
SSYNC;
SSYNC;
SAVE_ALL_SYS
#ifdef CONFIG_FRAME_POINTER
fp = 0;
#endif
ANOMALY_283_315_WORKAROUND(p5, r7)
/* Handle all stacked hardware errors
* To make sure we don't hang forever, only do it 10 times
*/
R0 = 0;
R2 = 10;
1:
P0.L = LO(ILAT);
P0.H = HI(ILAT);
R1 = [P0];
CC = BITTST(R1, EVT_IVHW_P);
IF ! CC JUMP 2f;
/* OK a hardware error is pending - clear it */
R1 = EVT_IVHW_P;
[P0] = R1;
R0 += 1;
CC = R1 == R2;
if CC JUMP 2f;
JUMP 1b;
2:
# We are going to dump something out, so make sure we print IPEND properly
p2.l = lo(IPEND);
p2.h = hi(IPEND);
r0 = [p2];
[sp + PT_IPEND] = r0;
/* set the EXCAUSE to HWERR for trap_c */
r0 = [sp + PT_SEQSTAT];
R1.L = LO(VEC_HWERR);
R1.H = HI(VEC_HWERR);
R0 = R0 | R1;
[sp + PT_SEQSTAT] = R0;
r0 = sp; /* stack frame pt_regs pointer argument ==> r0 */
SP += -12;
pseudo_long_call _trap_c, p5;
SP += 12;
#ifdef EBIU_ERRMST
/* make sure EBIU_ERRMST is clear */
p0.l = LO(EBIU_ERRMST);
p0.h = HI(EBIU_ERRMST);
r0.l = (CORE_ERROR | CORE_MERROR);
w[p0] = r0.l;
#endif
pseudo_long_call _ret_from_exception, p2;
.Lcommon_restore_all_sys:
RESTORE_ALL_SYS
rti;
ENDPROC(_evt_ivhw)
/* Interrupt routine for evt2 (NMI).
* For inner circle type details, please see:
* http://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:nmi
*/
ENTRY(_evt_nmi)
#ifndef CONFIG_NMI_WATCHDOG
.weak _evt_nmi
#else
/* Not take account of CPLBs, this handler will not return */
SAVE_ALL_SYS
r0 = sp;
r1 = retn;
[sp + PT_PC] = r1;
trace_buffer_save(p4,r5);
ANOMALY_283_315_WORKAROUND(p4, r5)
SP += -12;
call _do_nmi;
SP += 12;
1:
jump 1b;
#endif
rtn;
ENDPROC(_evt_nmi)
/* interrupt routine for core timer - 6 */
ENTRY(_evt_timer)
TIMER_INTERRUPT_ENTRY(EVT_IVTMR_P)
/* interrupt routine for evt7 - 7 */
ENTRY(_evt_evt7)
INTERRUPT_ENTRY(EVT_IVG7_P)
ENTRY(_evt_evt8)
INTERRUPT_ENTRY(EVT_IVG8_P)
ENTRY(_evt_evt9)
INTERRUPT_ENTRY(EVT_IVG9_P)
ENTRY(_evt_evt10)
INTERRUPT_ENTRY(EVT_IVG10_P)
ENTRY(_evt_evt11)
INTERRUPT_ENTRY(EVT_IVG11_P)
ENTRY(_evt_evt12)
INTERRUPT_ENTRY(EVT_IVG12_P)
ENTRY(_evt_evt13)
INTERRUPT_ENTRY(EVT_IVG13_P)
/* interrupt routine for system_call - 15 */
ENTRY(_evt_system_call)
SAVE_CONTEXT_SYSCALL
#ifdef CONFIG_FRAME_POINTER
fp = 0;
#endif
pseudo_long_call _system_call, p2;
jump .Lcommon_restore_context;
ENDPROC(_evt_system_call)
#ifdef CONFIG_IPIPE
/*
* __ipipe_call_irqtail: lowers the current priority level to EVT15
* before running a user-defined routine, then raises the priority
* level to EVT14 to prepare the caller for a normal interrupt
* return through RTI.
*
* We currently use this facility in two occasions:
*
* - to branch to __ipipe_irq_tail_hook as requested by a high
* priority domain after the pipeline delivered an interrupt,
* e.g. such as Xenomai, in order to start its rescheduling
* procedure, since we may not switch tasks when IRQ levels are
* nested on the Blackfin, so we have to fake an interrupt return
* so that we may reschedule immediately.
*
* - to branch to sync_root_irqs, in order to play any interrupt
* pending for the root domain (i.e. the Linux kernel). This lowers
* the core priority level enough so that Linux IRQ handlers may
* never delay interrupts handled by high priority domains; we defer
* those handlers until this point instead. This is a substitute
* to using a threaded interrupt model for the Linux kernel.
*
* r0: address of user-defined routine
* context: caller must have preempted EVT15, hw interrupts must be off.
*/
ENTRY(___ipipe_call_irqtail)
p0 = r0;
r0.l = 1f;
r0.h = 1f;
reti = r0;
rti;
1:
[--sp] = rets;
[--sp] = ( r7:4, p5:3 );
sp += -12;
call (p0);
sp += 12;
( r7:4, p5:3 ) = [sp++];
rets = [sp++];
#ifdef CONFIG_DEBUG_HWERR
/* enable irq14 & hwerr interrupt, until we transition to _evt_evt14 */
r0 = (EVT_IVG14 | EVT_IVHW | \
EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#else
/* Only enable irq14 interrupt, until we transition to _evt_evt14 */
r0 = (EVT_IVG14 | \
EVT_IRPTEN | EVT_EVX | EVT_NMI | EVT_RST | EVT_EMU);
#endif
sti r0;
raise 14; /* Branches to _evt_evt14 */
2:
jump 2b; /* Likely paranoid. */
ENDPROC(___ipipe_call_irqtail)
#endif /* CONFIG_IPIPE */