From c03913c62ddb751d2992e8a3d70e945229ed8e15 Mon Sep 17 00:00:00 2001
From: aiju <aiju@phicode.de>
Date: Fri, 13 Jul 2012 18:09:42 +0200
Subject: fixed multiboot booting

---
 sys/src/9/pc/l.s | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/sys/src/9/pc/l.s b/sys/src/9/pc/l.s
index d3e5f5201..128fde3d3 100644
--- a/sys/src/9/pc/l.s
+++ b/sys/src/9/pc/l.s
@@ -46,12 +46,28 @@ TEXT _multibootheader(SB), $0
 	LONG	$_startKADDR-KZERO(SB)		/* load_addr */
 	LONG	$edata-KZERO(SB)		/* load_end_addr */
 	LONG	$end-KZERO(SB)			/* bss_end_addr */
-	LONG	$_startKADDR-KZERO(SB)		/* entry_addr */
+	LONG	$_multibootentry-KZERO(SB)		/* entry_addr */
 	LONG	$0				/* mode_type */
 	LONG	$0				/* width */
 	LONG	$0				/* height */
 	LONG	$0				/* depth */
 
+TEXT _multibootentry(SB), $0
+	MOVL	$etext-KZERO(SB), SI
+	MOVL	SI, DI
+	ADDL	$0xfff, DI
+	ANDL	$~0xfff, DI
+	MOVL	$edata-KZERO(SB), CX
+	SUBL	DI, CX
+	ADDL	CX, SI
+	ADDL	CX, DI
+	STD
+	REP; MOVSB
+	CLD
+	MOVL	$_startPADDR(SB), AX
+	ANDL	$~KZERO, AX
+	JMP*	AX
+
 /*
  * In protected mode with paging turned off and segment registers setup
  * to linear map all memory. Entered via a jump to PADDR(entry),
-- 
cgit v1.2.3


From c612f9c41fd876c181f89472861245404cef65c5 Mon Sep 17 00:00:00 2001
From: aiju <aiju@phicode.de>
Date: Fri, 13 Jul 2012 18:52:39 +0200
Subject: multiboot: use initrd for config

---
 sys/src/9/pc/l.s    | 10 ++++++++++
 sys/src/9/pc/main.c | 16 ++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/sys/src/9/pc/l.s b/sys/src/9/pc/l.s
index 128fde3d3..83e6e91a3 100644
--- a/sys/src/9/pc/l.s
+++ b/sys/src/9/pc/l.s
@@ -52,6 +52,10 @@ TEXT _multibootheader(SB), $0
 	LONG	$0				/* height */
 	LONG	$0				/* depth */
 
+/* 
+ * the kernel expects the data segment to be page-aligned
+ * multiboot bootloaders put the data segment right behind text
+ */
 TEXT _multibootentry(SB), $0
 	MOVL	$etext-KZERO(SB), SI
 	MOVL	SI, DI
@@ -64,10 +68,16 @@ TEXT _multibootentry(SB), $0
 	STD
 	REP; MOVSB
 	CLD
+	ADDL	$KZERO, BX
+	MOVL	BX, multiboot-KZERO(SB)
 	MOVL	$_startPADDR(SB), AX
 	ANDL	$~KZERO, AX
 	JMP*	AX
 
+/* multiboot structure pointer */
+TEXT multiboot(SB), $0
+	LONG	$0
+
 /*
  * In protected mode with paging turned off and segment registers setup
  * to linear map all memory. Entered via a jump to PADDR(entry),
diff --git a/sys/src/9/pc/main.c b/sys/src/9/pc/main.c
index 1ea96d6c7..71c469650 100644
--- a/sys/src/9/pc/main.c
+++ b/sys/src/9/pc/main.c
@@ -37,6 +37,22 @@ options(void)
 {
 	long i, n;
 	char *cp, *line[MAXCONF], *p, *q;
+	ulong *m, l;
+	extern ulong *multiboot;
+
+	if(multiboot != nil){
+		cp = BOOTARGS;
+		*cp = 0;
+		if((*multiboot & 8) != 0 && multiboot[5] > 0){
+			m = KADDR(multiboot[6]);
+			l = m[1] - m[0];
+			m = KADDR(m[0]);
+			if(l >= BOOTARGSLEN)
+				l = BOOTARGSLEN - 1;
+			memmove(cp, m, l);
+			cp[l] = 0;
+		}
+	}
 
 	/*
 	 *  parse configuration args from dos file plan9.ini
-- 
cgit v1.2.3