Attempt to adacpt acorn26 to idlelwp. This is untested.

OK'd by Ben Harris

sys/arch/acorn26/acorn26/cpuswitch.c

@@ -1,4 +1,4 @@
-/*	$NetBSD: cpuswitch.c,v 1.10 2007/03/04 05:59:03 christos Exp $	*/
+/*	$NetBSD: cpuswitch.c,v 1.11 2007/06/01 07:04:53 skrll Exp $	*/
 
 /*
  * Copyright (c) 2000 Ben Harris.
@@ -38,7 +38,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: cpuswitch.c,v 1.10 2007/03/04 05:59:03 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: cpuswitch.c,v 1.11 2007/06/01 07:04:53 skrll Exp $");
 
 #include "opt_lockdebug.h"
 
@@ -48,100 +48,24 @@ __KERNEL_RCSID(0, "$NetBSD: cpuswitch.c,v 1.10 2007/03/04 05:59:03 christos Exp
 #include <sys/systm.h>
 #include <sys/user.h>
 #include <sys/ras.h>
+#include <sys/cpu.h>
 
 #include <uvm/uvm_extern.h>
 
 #include <machine/frame.h>
 #include <machine/machdep.h>
 
-void idle(void);
-
 struct pcb *curpcb;
 
-/*
- * Idle
- */
-void
-idle()
-{
-
-	sched_unlock_idle();
-	spl0();
-	while (sched_whichqs == 0)
-		continue;
-	splhigh();
-	sched_lock_idle();
-}
-
 extern int want_resched; /* XXX should be in <machine/cpu.h> */
 
-/*
- * Find the highest-priority runnable process and switch to it.
- *
- * If l1 is NULL, we're switching away from a dying process.  We hope it's
- * safe to run on its stack until the switch.
- */
-int
-cpu_switch(struct lwp *l1, struct lwp *newl)
-{
-	int which;
-	struct prochd *q;
-	struct lwp *l2;
-	struct proc *p2;
-	struct switchframe *dummy;
-	/*
-	 * We enter here with interrupts blocked and sched_lock held.
-	 */
-
-#if 0
-	printf("cpu_switch: %p ->", l1);
-#endif
-	curlwp = NULL;
-	curpcb = NULL;
-	while (sched_whichqs == 0)
-		idle();
-	which = ffs(sched_whichqs) - 1;
-	q = &sched_qs[which];
-	l2 = q->ph_link;
-	remrunqueue(l2);
-	want_resched = 0;
-	sched_unlock_idle();
-	/* p->p_cpu initialized in fork1() for single-processor */
-	l2->l_stat = LSONPROC;
-	curlwp = l2;
-	curpcb = &curlwp->l_addr->u_pcb;
-#if 0
-	printf(" %p\n", l2);
-#endif
-	if (l2 == l1)
-		return (0);
-	if (l1 != NULL)
-		pmap_deactivate(l1);
-	pmap_activate(l2);
-
-	/* Check for Restartable Atomic Sequences. */
-	p2 = l2->l_proc;
-	if (!LIST_EMPTY(&p2->p_raslist)) {
-		struct trapframe *tf = l2->l_addr->u_pcb.pcb_tf;
-		void *pc;
-
-		pc = ras_lookup(p2, (void *)(tf->tf_r15 & R15_PC));
-		if (pc != (void *) -1)
-			tf->tf_r15 = (tf->tf_r15 & ~R15_PC) | (register_t) pc;
-	}
-
-	cpu_loswitch(l1 ? &l1->l_addr->u_pcb.pcb_sf : &dummy,
-	    l2->l_addr->u_pcb.pcb_sf);
-	/* We only get back here after the other process has run. */
-	return (1);
-}
-
 /*
  * Switch to the indicated lwp.
  */
-void
+lwp_t *
-cpu_switchto(struct lwp *old, struct lwp *new)
+cpu_switchto(lwp_t *old, lwp_t *new)
 {
+	struct proc *p2;
 
 	/*
 	 * We enter here with interrupts blocked and sched_lock held.
@@ -150,14 +74,23 @@ cpu_switchto(struct lwp *old, struct lwp *new)
 #if 0
 	printf("cpu_switchto: %p -> %p", old, new);
 #endif
-	want_resched = 0;
+
-	/* p->p_cpu initialized in fork1() for single-processor */
-	new->l_stat = LSONPROC;
 	curlwp = new;
 	curpcb = &curlwp->l_addr->u_pcb;
-	sched_unlock_idle();
+
-	pmap_deactivate(old);
+	if ((new->l_flag & LW_SYSTEM) == 0) {
-	pmap_activate(new);
+		/* Check for Restartable Atomic Sequences. */
-	cpu_loswitch(&old->l_addr->u_pcb.pcb_sf, new->l_addr->u_pcb.pcb_sf);
+		p2 = new->l_proc;
-	/* We only get back here after the other process has run. */
+		if (!LIST_EMPTY(&p2->p_raslist)) {
+			struct trapframe *tf = new->l_addr->u_pcb.pcb_tf;
+			void *pc;
+
+			pc = ras_lookup(p2, (void *)(tf->tf_r15 & R15_PC));
+			if (pc != (void *) -1)
+				tf->tf_r15 = (tf->tf_r15 & ~R15_PC) |
+				    (register_t) pc;
+		}
+	}
+
+	return cpu_loswitch(old, new);
 }

sys/arch/acorn26/acorn26/genassym.cf

@@ -1,4 +1,4 @@
-# $NetBSD: genassym.cf,v 1.7 2006/10/08 12:22:35 bjh21 Exp $
+# $NetBSD: genassym.cf,v 1.8 2007/06/01 07:04:53 skrll Exp $
 #
 # Copyright (c) 1999 Ben Harris
 # All rights reserved.
@@ -47,6 +47,7 @@ endif
 define	__PROG26	1
 
 define	U_PCB		offsetof(struct user, u_pcb)
+define	PCB_SF		offsetof(struct pcb, pcb_sf)
 define	PCB_ONFAULT	offsetof(struct pcb, pcb_onfault)
 define	L_ADDR		offsetof(struct lwp, l_addr)
 
@@ -73,4 +74,3 @@ define	EFS_RX_FLAGS	offsetof(struct eca_fiqstate, efs_rx_flags)
 define	EFS_RX_MYADDR	offsetof(struct eca_fiqstate, efs_rx_myaddr)
 define	EFS_TX_CURMBUF	offsetof(struct eca_fiqstate, efs_tx_curmbuf)
 endif
-

sys/arch/acorn26/acorn26/locore.S

@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.11 2007/02/28 23:47:09 bjh21 Exp $ */
+/* $NetBSD: locore.S,v 1.12 2007/06/01 07:04:54 skrll Exp $ */
 /*
  * Copyright (c) 1998, 1999, 2000 Ben Harris
  * Copyright (C) 1994-1997 Mark Brinicombe
@@ -383,44 +383,62 @@ ENTRY_NP(get_r15)
 	mov	r0, r14
 	mov	r15, lr
 
-	/*
+/*
-	 * Low-level context-switch operation.  cpu_switch() is in C -- this
+ * Low-level context-switch operation.  cpu_switchto() is in C -- this
-	 * just handles the bits that can't be done in C.
+ * just handles the bits that can't be done in C.
-	 *
+ *
-	 * void cpu_loswitch(struct switchframe **fromp,
+ * struct lwp *cpu_loswitch(struct lwp *oldl, struct lwp *newl)
-	 *		     struct switchframe *to)
+ *
-	 *
+ * We leave a switchframe on the stack pointed to by and save this in
-	 * We leave a switchframe on the stack pointed to by fromp,
+ * oldl's PCB, and return to the context in newl.  This should be called at
-	 * and return to the context in to.  This should be called in
+ * splhigh();
-	 * splhigh();
+ *
-	 */
+ * r0 and r1 must be left intact as they're needed by lwp_startup in
-/* LINTSTUB: Func: void cpu_loswitch(struct switchframe **fromp, struct switchframe *to) */
+ * lwp_trampoline
+ */
+/* LINTSTUB: Func: struct lwp *cpu_loswitch(struct lwp *oldl, struct lwp *newl) */
 ENTRY(cpu_loswitch)
+	teq	r0, #0x00000000
+	beq	Lswitch_exited
+
+	ldr	r3, [r0, #(L_ADDR)]
+	add	r3, r3, #PCB_SF		/* r3 =  &old->l_addr->u_pcb.pcb_sf */
+
 	mov	r2, sp			/* Temporary stack pointer */
 	stmfd	r2!, {r4-r11, r13-r14}	/* Save all relevant registers */
-	str	r2, [r0]		/* Save switchframe pointer */
+	str	r2, [r3]		/* Save switchframe pointer */
-	ldmfd	r1, {r4-r11, r13-r14}	/* Restore from old switchframe */
+
+Lswitch_exited:
+
+	ldr	r2, [r1, #(L_ADDR)]
+	ldr	r3, [r2, #(PCB_SF)]	/* r3 = new->l_addr->u_pcb.pcb_sf; */
+
+	ldmfd	r3, {r4-r11, r13-r14}	/* Restore from old switchframe */
 	mov	pc, r14			/* and return */
 
-	/*
+/*
-	 * This funny little routine implements starting a process.
+ * This funny little routine implements starting a process.
-	 * It's called by cpu_loswitch returning from a faked
+ * It's called by cpu_loswitch returning from a faked
-	 * switchframe set up by cpu_fork(), and gets
+ * switchframe set up by cpu_lwp_fork(), and gets
-	 * the function it's meant to enter passed in R4 with its
+ * the function it's meant to enter passed in R4 with its
-	 * argument in R5.  If that function's NULL, or if it returns,
+ * argument in R5.  If that function's NULL, or if it returns,
-	 * we hope there's a trapframe on the stack that'll take us
+ * we hope there's a trapframe on the stack that'll take us
-	 * back to userland.
+ * back to userland.
-	 */
+ *
-ENTRY(proc_trampoline)
+ * cpu_loswitch also ensures that r0 is oldl and r1 is newl
+ * for our call to lwp_startup.
+ */
+ENTRY(lwp_trampoline)
 	mov	fp, #0			/* Tie knot in top of stack */
+	bl	_C_LABEL(lwp_startup)
 	mov	r0, #0
-	bl	_C_LABEL(lowerspl)		/* spl0() */
+	bl	_C_LABEL(lowerspl)	/* spl0() */
 	cmp	r4, #0			/* Function to call? */
-	beq	Lproc_trampoline_nofunc
+	beq	Llwp_trampoline_nofunc
 	mov	r0, r5
 	mov	r14, pc			/* Save return address */
 	mov	pc, r4			/* Call function */
-Lproc_trampoline_nofunc:
+Llwp_trampoline_nofunc:
 	b	pull_trapframe
 
 /* LINTSTUB: Func: int setjmp(label_t *l) */
@@ -444,4 +462,4 @@ ENTRY(cpu_Debugger)
 	ldmfd	r13!, {pc}
 #endif
 
-RCSID("$NetBSD: locore.S,v 1.11 2007/02/28 23:47:09 bjh21 Exp $")
+RCSID("$NetBSD: locore.S,v 1.12 2007/06/01 07:04:54 skrll Exp $")

sys/arch/acorn26/acorn26/machdep.c

@@ -1,4 +1,4 @@
-/* $NetBSD: machdep.c,v 1.19 2007/02/22 04:47:28 thorpej Exp $ */
+/* $NetBSD: machdep.c,v 1.20 2007/06/01 07:04:54 skrll Exp $ */
 
 /*-
  * Copyright (c) 1998 Ben Harris
@@ -32,7 +32,7 @@
 
 #include <sys/param.h>
 
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.19 2007/02/22 04:47:28 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.20 2007/06/01 07:04:54 skrll Exp $");
 
 #include <sys/buf.h>
 #include <sys/kernel.h>
@@ -41,6 +41,7 @@ __KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.19 2007/02/22 04:47:28 thorpej Exp $")
 #include <sys/reboot.h>
 #include <sys/sysctl.h>
 #include <sys/systm.h>
+#include <sys/cpu.h>
 
 #include <dev/i2c/i2cvar.h>
 #include <dev/i2c/pcf8583var.h>
@@ -214,3 +215,16 @@ cmos_write(int location, int value)
 	return (pcfrtc_bootstrap_write(acorn26_i2c_tag, 0x50,
 	    location, &val, 1));
 }
+
+void
+cpu_need_resched(struct cpu_info *ci, int flags)
+{
+	bool immed = (flags & RESCHED_IMMED) != 0;
+
+	if (want_resched && !immed)
+		return;
+
+	want_resched = 1;
+	if (curlwp != ci->ci_data.cpu_idlelwp)
+		setsoftast();
+}

sys/arch/acorn26/include/machdep.h

@@ -1,4 +1,4 @@
-/* $NetBSD: machdep.h,v 1.2 2002/03/24 23:37:43 bjh21 Exp $ */
+/* $NetBSD: machdep.h,v 1.3 2007/06/01 07:04:54 skrll Exp $ */
 /*-
  * Copyright (c) 1998 Ben Harris
  * All rights reserved.
@@ -55,8 +55,8 @@ extern void int_on	__P((void));
 extern void int_off	__P((void));
 extern void fiq_on	__P((void));
 extern void fiq_off	__P((void));
-extern void cpu_loswitch(struct switchframe **, struct switchframe *);
+extern struct lwp *cpu_loswitch(struct lwp *, struct lwp *);
-extern void proc_trampoline(void); /* not quite true */
+extern void lwp_trampoline(void); /* not quite true */
 
 /* pmap.c */
 extern register_t update_memc	__P((register_t, register_t));