From 58085efd69fe6cf43125d0af874487a86f1e21b9 Mon Sep 17 00:00:00 2001
From: Paul Mundt <lethal@linux-sh.org>
Date: Wed, 17 Dec 2008 15:33:43 +0900
Subject: [PATCH] --- yaml --- r: 120151 b: refs/heads/master c:
 740a3e677b70181d5e2b1458a27891209e3bf635 h: refs/heads/master i:   120149:
 784878215925baa0ebddf1beae3113fbba418dd2   120147:
 11e1fae649594c99080ea808c8a6ed6612b02988   120143:
 7877cadc5b1f9bb52832dfb2be2f9d1a8c4773d8 v: v3

---
 [refs]                         |  2 +-
 trunk/arch/sh/Kconfig.debug    | 15 ++++++++++++---
 trunk/arch/sh/kernel/head_32.S | 12 ++++++++++--
 3 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/[refs] b/[refs]
index 253259128ee6..c292453270e8 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8a655053ca1593dd160dac2a4ee638fdec037d86
+refs/heads/master: 740a3e677b70181d5e2b1458a27891209e3bf635
diff --git a/trunk/arch/sh/Kconfig.debug b/trunk/arch/sh/Kconfig.debug
index 834a2d24342b..eef2fa940ce0 100644
--- a/trunk/arch/sh/Kconfig.debug
+++ b/trunk/arch/sh/Kconfig.debug
@@ -98,6 +98,18 @@ config IRQSTACKS
 	  for handling hard and soft interrupts.  This can help avoid
 	  overflowing the process kernel stacks.
 
+config SH_NO_BSS_INIT
+	bool "Avoid zeroing BSS (to speed-up startup on suitable platforms)"
+	depends on DEBUG_KERNEL
+	default n
+	help
+	  If running in painfully slow environments, such as an RTL
+	  simulation or from remote memory via SHdebug, where the memory
+	  can already be gauranteed to ber zeroed on boot, say Y.
+
+	  For all other cases, say N. If this option seems perplexing, or
+	  you aren't sure, say N.
+
 config MORE_COMPILE_OPTIONS
 	bool "Add any additional compile options"
 	help
@@ -125,9 +137,6 @@ config SH_ALPHANUMERIC
 	bool "Enable debug outputs to on-board alphanumeric display"
 	depends on SH_CAYMAN
 
-config SH_NO_BSS_INIT
-	bool "Avoid zeroing BSS (to speed-up startup on suitable platforms)"
-
 endif
 
 endmenu
diff --git a/trunk/arch/sh/kernel/head_32.S b/trunk/arch/sh/kernel/head_32.S
index ae0a382a82eb..788605ff7088 100644
--- a/trunk/arch/sh/kernel/head_32.S
+++ b/trunk/arch/sh/kernel/head_32.S
@@ -80,8 +80,14 @@ ENTRY(_stext)
 	mov.l	7f, r0
 	ldc	r0, r7_bank	! ... and initial thread_info
 #endif
-	
-	!			Clear BSS area
+
+#ifndef CONFIG_SH_NO_BSS_INIT
+	/*
+	 * Don't clear BSS if running on slow platforms such as an RTL simulation,
+	 * remote memory via SHdebug link, etc.  For these the memory can be guaranteed
+	 * to be all zero on boot anyway.
+	 */
+				! Clear BSS area
 #ifdef CONFIG_SMP	
 	mov.l	3f, r0
 	cmp/eq	#0, r0		! skip clear if set to zero
@@ -97,6 +103,8 @@ ENTRY(_stext)
 	 mov.l	r0,@-r2
 
 10:		
+#endif
+
 	!			Additional CPU initialization
 	mov.l	6f, r0
 	jsr	@r0