5 files changed, 117 insertions, 8 deletions
diff --git a/sys/arch/sparc64/include/mdesc.h b/sys/arch/sparc64/include/mdesc.h
index 5e5581bd739..bacc926141a 100644
--- a/sys/arch/sparc64/include/mdesc.h
+++ b/sys/arch/sparc64/include/mdesc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdesc.h,v 1.2 2009/05/10 12:37:01 kettenis Exp $	*/
+/*	$OpenBSD: mdesc.h,v 1.3 2014/11/30 22:26:14 kettenis Exp $	*/
 /*
  * Copyright (c) 2009 Mark Kettenis
  *
@@ -42,7 +42,9 @@ extern size_t mdesc_len;
 
 void	 mdesc_init(void);
 uint64_t mdesc_get_prop_val(int, const char *);
-const char * mdesc_get_prop_str(int, const char *);
+const char *mdesc_get_prop_str(int, const char *);
+const char *mdesc_get_prop_data(int, const char *, size_t *);
 int	mdesc_find(const char *, uint64_t);
 int	mdesc_find_child(int, const char *, uint64_t);
+int	mdesc_find_node(const char *);
 #endif
diff --git a/sys/arch/sparc64/sparc64/autoconf.c b/sys/arch/sparc64/sparc64/autoconf.c
index 956262d6389..2a1a7b020e9 100644
--- a/sys/arch/sparc64/sparc64/autoconf.c
+++ b/sys/arch/sparc64/sparc64/autoconf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: autoconf.c,v 1.122 2014/11/26 20:06:53 stsp Exp $	*/
+/*	$OpenBSD: autoconf.c,v 1.123 2014/11/30 22:26:14 kettenis Exp $	*/
 /*	$NetBSD: autoconf.c,v 1.51 2001/07/24 19:32:11 eeh Exp $ */
 
 /*
@@ -648,8 +648,46 @@ void
 cpu_configure()
 {
 #ifdef SUN4V
-	if (CPU_ISSUN4V)
+	int pause = 0;
+
+	if (CPU_ISSUN4V) {
+		const char *prop;
+		size_t len;
+		int idx;
+
 		mdesc_init();
+		idx = mdesc_find_node("cpu");
+		prop = mdesc_get_prop_data(idx, "hwcap-list", &len);
+		if (prop) {
+			while (len > 0) {
+				if (strcmp(prop, "pause") == 0)
+					pause = 1;
+				len -= strlen(prop) + 1;
+				prop += strlen(prop) + 1;
+			}
+		}
+	}
+
+	if (pause) {
+		struct sun4v_patch {
+			u_int32_t addr;
+			u_int32_t insn;
+		} *p;
+		paddr_t pa;
+
+		extern struct sun4v_patch sun4v_pause_patch;
+		extern struct sun4v_patch sun4v_pause_patch_end;
+
+		/*
+		 * Use physical addresses to patch since kernel .text
+		 * is already mapped read-only at this point.
+		 */
+		for (p = &sun4v_pause_patch; p < &sun4v_pause_patch_end; p++) {
+			pmap_extract(pmap_kernel(), (vaddr_t)p->addr, &pa);
+			stwa(pa, ASI_PHYS_NON_CACHED, p->insn);
+			flush((void *)(vaddr_t)p->addr);
+		}
+	}
 #endif
 
 	if (obd.version == BOOTDATA_VERSION &&
diff --git a/sys/arch/sparc64/sparc64/lock_machdep.c b/sys/arch/sparc64/sparc64/lock_machdep.c
index 92d59254703..f361ffb8f7c 100644
--- a/sys/arch/sparc64/sparc64/lock_machdep.c
+++ b/sys/arch/sparc64/sparc64/lock_machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lock_machdep.c,v 1.7 2014/03/29 18:09:30 guenther Exp $	*/
+/*	$OpenBSD: lock_machdep.c,v 1.8 2014/11/30 22:26:14 kettenis Exp $	*/
 
 /*
  * Copyright (c) 2007 Artur Grabowski <art@openbsd.org>
@@ -53,7 +53,10 @@ extern int __mp_lock_spinout;
  * effectively nops, executing them on earlier non-CMT processors is
  * harmless, so we make this the default.
  *
- * On SPARC64 VI and it successors we execute the processor-specific
+ * On SPARC T4 and later, we can use the processor-specific pause
+ * instruction.
+ *
+ * On SPARC64 VI and its successors we execute the processor-specific
  * sleep instruction.
  */
 static __inline void
@@ -63,6 +66,14 @@ __mp_lock_spin_hook(void)
 		"999:	rd	%%ccr, %%g0			\n"
 		"	rd	%%ccr, %%g0			\n"
 		"	rd	%%ccr, %%g0			\n"
+		"	.section .sun4v_pause_patch, \"ax\"	\n"
+		"	.word	999b				\n"
+		"	.word	0xb7802080	! pause	128	\n"
+		"	.word	999b + 4			\n"
+		"	nop					\n"
+		"	.word	999b + 8			\n"
+		"	nop					\n"
+		"	.previous				\n"
 		"	.section .sun4u_mtp_patch, \"ax\"	\n"
 		"	.word	999b				\n"
 		"	.word	0x81b01060	! sleep		\n"
diff --git a/sys/arch/sparc64/sparc64/locore.s b/sys/arch/sparc64/sparc64/locore.s
index f0d35a494b2..dfec6907347 100644
--- a/sys/arch/sparc64/sparc64/locore.s
+++ b/sys/arch/sparc64/sparc64/locore.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.s,v 1.178 2014/11/24 10:55:49 kettenis Exp $	*/
+/*	$OpenBSD: locore.s,v 1.179 2014/11/30 22:26:14 kettenis Exp $	*/
 /*	$NetBSD: locore.s,v 1.137 2001/08/13 06:10:10 jdolecek Exp $	*/
 
 /*
@@ -106,6 +106,16 @@ _C_LABEL(sun4v_patch):
 _C_LABEL(sun4v_patch_end):
 	.previous
 
+	.section	.sun4v_pause_patch, "ax"
+	.globl _C_LABEL(sun4v_pause_patch)
+_C_LABEL(sun4v_pause_patch):
+	.previous
+
+	.section	.sun4v_pause_patch_end, "ax"
+	.globl _C_LABEL(sun4v_pause_patch_end)
+_C_LABEL(sun4v_pause_patch_end):
+	.previous
+
 #ifdef MULTIPROCESSOR
 	.section	.sun4v_mp_patch, "ax"
 	.globl _C_LABEL(sun4v_mp_patch)
diff --git a/sys/arch/sparc64/sparc64/mdesc.c b/sys/arch/sparc64/sparc64/mdesc.c
index 2d905f4ef72..73d51353bc2 100644
--- a/sys/arch/sparc64/sparc64/mdesc.c
+++ b/sys/arch/sparc64/sparc64/mdesc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdesc.c,v 1.6 2014/11/16 12:30:59 deraadt Exp $	*/
+/*	$OpenBSD: mdesc.c,v 1.7 2014/11/30 22:26:15 kettenis Exp $	*/
 /*
  * Copyright (c) 2009 Mark Kettenis
  *
@@ -138,6 +138,32 @@ mdesc_get_prop_str(int idx, const char *name)
 	return (NULL);
 }
 
+const char *
+mdesc_get_prop_data(int idx, const char *name, size_t *len)
+{
+	struct md_header *hdr;
+	struct md_element *elem;
+	const char *name_blk;
+	const char *data_blk;
+	const char *str;
+
+	hdr = (struct md_header *)mdesc;
+	elem = (struct md_element *)(mdesc + sizeof(struct md_header));
+	name_blk = mdesc + sizeof(struct md_header) + hdr->node_blk_sz;
+	data_blk = name_blk + hdr->name_blk_sz;
+
+	while (elem[idx].tag != 'E') {
+		str = name_blk + elem[idx].name_offset;
+		if (elem[idx].tag == 'd' && strcmp(str, name) == 0) {
+			*len = elem[idx].d.y.data_len;
+			return (data_blk + elem[idx].d.y.data_offset);
+		}
+		idx++;
+	}
+
+	return (NULL);
+}
+
 int
 mdesc_find(const char *name, uint64_t cfg_handle)
 {
@@ -188,3 +214,25 @@ mdesc_find_child(int idx, const char *name, uint64_t cfg_handle)
 
 	return (-1);
 }
+
+int
+mdesc_find_node(const char *name)
+{
+	struct md_header *hdr;
+	struct md_element *elem;
+	const char *name_blk;
+	const char *str;
+	int idx;
+
+	hdr = (struct md_header *)mdesc;
+	elem = (struct md_element *)(mdesc + sizeof(struct md_header));
+	name_blk = mdesc + sizeof(struct md_header) + hdr->node_blk_sz;
+
+	for (idx = 0; elem[idx].tag == 'N'; idx = elem[idx].d.val) {
+		str = name_blk + elem[idx].name_offset;
+		if (str && strcmp(str, name) == 0)
+			return (idx);
+	}
+
+	return (-1);
+}