Initial import

1 files changed, 326 insertions, 0 deletions

diff --git a/arch/blackfin/mach-common/interrupt.S b/arch/blackfin/mach-common/interrupt.S
new file mode 100644
index 000000000..469ce7282
--- /dev/null
+++ b/arch/blackfin/mach-common/interrupt.S
@@ -0,0 +1,326 @@
+/*
+ * 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 feature in two occasions:
+ *
+ * - before branching 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.
+ *
+ * - before branching to __ipipe_sync_root(), 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 */