allow forced fpu emulation through a sysctl

3 files changed, 33 insertions, 11 deletions

diff --git a/sys/arch/hppa/hppa/locore.S b/sys/arch/hppa/hppa/locore.S
index 218c95974b2..2d0f2a225fa 100644
--- a/sys/arch/hppa/hppa/locore.S
+++ b/sys/arch/hppa/hppa/locore.S
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.S,v 1.134 2004/06/13 21:49:14 niklas Exp $	*/
+/*	$OpenBSD: locore.S,v 1.135 2004/06/30 18:18:54 mickey Exp $	*/
 
 /*
  * Copyright (c) 1998-2004 Michael Shalayeff
@@ -158,6 +158,7 @@ cpu_itmr			/* itmr value at the most recent clk int */
 	BSS(fpu_curpcb, 4)	/* pcb of the fpu owner */
 	.export fpu_enable, data
 	BSS(fpu_enable, 4)	/* bits to set in the ccr to enable fpu */
+	BSS(cpu_fpuena, 4)	/* enable FPU, otherwise force emulate */
 	BSS(fpu_scratch, 16)	/* FPU scratch space, enough for a quad */
 	.export hppa_vtop, data
 	BSS(hppa_vtop, 4)	/* a vtop translation table addr (pa=va) */
@@ -1062,14 +1063,19 @@ ENTRY(TLABEL(emu),0)
 	 * or the trap will be generted later.
 	 */
 
+	ldil	L%cpu_fpuena, r1
+	ldw	R%cpu_fpuena(r1), r9
+	comib,=	0, r9, $fpusw_emu
+	ldil	L%fpu_curpcb, r1
+
 	/* if we are already enabled and hit again, emulate */
 	mfctl	ccr, r1
 	extru,<> r1, 25, 2, r0
 	b,n	$fpusw_set
 	nop
 
+$fpusw_emu
 	mtctl	r0, ccr		/* cause a reload after exception */
-	ldil	L%fpu_curpcb, r1
 	stw	r0, R%fpu_curpcb(r1)
 #if 0
 	/* here we emulate the fld/fst */
@@ -1317,7 +1323,7 @@ $tlbd_l
 	ldw	0(r17), r24
 	VTAG
 	sub,<>	r16, r24, r0
-	stw	r25, 4(r17)
+	stw	r0, 0(r17)
 #endif
 	TLB_STATS_AFT(tlbd)
 	rfir
diff --git a/sys/arch/hppa/hppa/machdep.c b/sys/arch/hppa/hppa/machdep.c
index 6fca2b95b01..e4c871a034d 100644
--- a/sys/arch/hppa/hppa/machdep.c
+++ b/sys/arch/hppa/hppa/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.130 2004/05/13 15:09:19 mickey Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.131 2004/06/30 18:18:54 mickey Exp $	*/
 
 /*
  * Copyright (c) 1999-2003 Michael Shalayeff
@@ -436,6 +436,7 @@ cpuid()
 	extern u_int trap_ep_T_ITLBMISSNA[];
 
 	extern u_int fpu_enable;
+	extern int cpu_fpuena;
 	struct pdc_cpuid pdc_cpuid PDC_ALIGNMENT;
 	const struct hppa_cpu_typed *p = NULL;
 	u_int cpu_features;
@@ -469,12 +470,14 @@ cpuid()
 	/* locate coprocessors and SFUs */
 	bzero(&pdc_coproc, sizeof(pdc_coproc));
 	if ((error = pdc_call((iodcio_t)pdc, 0, PDC_COPROC, PDC_COPROC_DFLT,
-	    &pdc_coproc, 0, 0, 0, 0)) < 0)
+	    &pdc_coproc, 0, 0, 0, 0)) < 0) {
 		printf("WARNING: PDC_COPROC error %d\n", error);
-	else {
+		cpu_fpuena = 0;
+	} else {
 		printf("pdc_coproc: 0x%x, 0x%x\n", pdc_coproc.ccr_enable,
 		    pdc_coproc.ccr_present);
 		fpu_enable = pdc_coproc.ccr_enable & CCR_MASK;
+		cpu_fpuena = 1;
 	}
 
 	/* BTLB params */
@@ -527,9 +530,11 @@ cpuid()
 		printf("WARNING: UNKNOWN CPU TYPE; GOOD LUCK "
 		    "(type 0x%x, features 0x%x)\n", cpu_type, cpu_features);
 		p = cpu_types;
-	} else if ((p->type == hpcxl || p->type == hpcxl2) && !fpu_enable)
+	} else if ((p->type == hpcxl || p->type == hpcxl2) && !fpu_enable) {
 		/* we know PCXL and PCXL2 do not exist w/o FPU */
 		fpu_enable = 0xc0;
+		cpu_fpuena = 1;
+	}
 
 	/*
 	 * TODO: HPT on 7200 is not currently supported
@@ -1216,10 +1221,9 @@ setregs(p, pack, stack, retval)
 	fdcache(HPPA_SID_KERNEL, (vaddr_t)pcb->pcb_fpregs, 8 * 4);
 	if (tf->tf_cr30 == fpu_curpcb) {
 		fpu_curpcb = 0;
-		/* force an fpu ctxsw, we'll not be hugged by the cpu_switch */
+		/* force an fpu ctxsw, we won't be hugged by the cpu_switch */
 		mtctl(0, CR_CCR);
 	}
-
 	retval[1] = 0;
 }
 
@@ -1459,7 +1463,10 @@ cpu_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
 	size_t newlen;
 	struct proc *p;
 {
+	extern paddr_t fpu_curpcb;	/* from locore.S */
+	extern int cpu_fpuena;
 	dev_t consdev;
+
 	/* all sysctl names at this level are terminal */
 	if (namelen != 1)
 		return (ENOTDIR);	/* overloaded */
@@ -1471,6 +1478,13 @@ cpu_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
 			consdev = NODEV;
 		return (sysctl_rdstruct(oldp, oldlenp, newp, &consdev,
 		    sizeof consdev));
+	case CPU_FPU:
+		if (fpu_curpcb) {
+			fpu_save(fpu_curpcb);
+			fpu_curpcb = 0;
+			mtctl(0, CR_CCR);
+		}
+		return (sysctl_int(oldp, oldlenp, newp, newlen, &cpu_fpuena));
 	default:
 		return (EOPNOTSUPP);
 	}
diff --git a/sys/arch/hppa/include/cpu.h b/sys/arch/hppa/include/cpu.h
index 5eb720ab0e9..629f346bacb 100644
--- a/sys/arch/hppa/include/cpu.h
+++ b/sys/arch/hppa/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.43 2004/06/13 21:49:14 niklas Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.44 2004/06/30 18:18:54 mickey Exp $	*/
 
 /*
  * Copyright (c) 2000-2004 Michael Shalayeff
@@ -164,11 +164,13 @@ int	cpu_dump(void);
  * CTL_MACHDEP definitions.
  */
 #define	CPU_CONSDEV		1	/* dev_t: console terminal device */
-#define	CPU_MAXID		2	/* number of valid machdep ids */
+#define	CPU_FPU			2	/* int: fpu present/enabled */
+#define	CPU_MAXID		3	/* number of valid machdep ids */
 
 #define CTL_MACHDEP_NAMES { \
 	{ 0, 0 }, \
 	{ "console_device", CTLTYPE_STRUCT }, \
+	{ "fpu", CTLTYPE_INT }, \
 }
 #endif