[PATCH] libpayload: Add multiboot support

Make libpayload applications multiboot compatible.  Add the
multiboot OS table and grok the loader table, especially the
memory map and the command line.  This makes libpayload 
applications loadable by GRUB.

Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Acked-by: Peter Stuge <peter@stuge.se>


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@3673 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

5 files changed, 140 insertions, 3 deletions

diff --git a/payloads/libpayload/i386/Makefile.inc b/payloads/libpayload/i386/Makefile.inc
index bb6bcb5a11..40d2699062 100644
--- a/payloads/libpayload/i386/Makefile.inc
+++ b/payloads/libpayload/i386/Makefile.inc
@@ -31,3 +31,5 @@ TARGETS-y += i386/head.S.o i386/main.o i386/sysinfo.o
 TARGETS-y += i386/timer.o i386/coreboot.o i386/util.S.o
 TARGETS-y += i386/exec.S.o i386/virtual.o
 
+# Multiboot support is configurable
+TARGETS-$(CONFIG_MULTIBOOT) += i386/multiboot.o
diff --git a/payloads/libpayload/i386/head.S b/payloads/libpayload/i386/head.S
index 54f60e1469..db18a5195f 100644
--- a/payloads/libpayload/i386/head.S
+++ b/payloads/libpayload/i386/head.S
@@ -27,6 +27,7 @@
  * SUCH DAMAGE.
  */
 
+	.code32
 	.global _entry, _leave
 	.text
 	.align 4
@@ -42,6 +43,21 @@ _entry:
 	/* We're back - go back to the bootloader. */
 	ret
 
+	.align 4
+
+#define MB_MAGIC 0x1BADB002
+#define MB_FLAGS 0x00010003
+
+mb_header:
+	.long MB_MAGIC
+	.long MB_FLAGS
+	.long -(MB_MAGIC + MB_FLAGS)
+	.long mb_header
+	.long _start
+	.long _edata
+	.long _end
+	.long _init
+
 /*
  * This function saves off the previous stack and switches us to our
  * own execution environment.
@@ -53,6 +69,11 @@ _init:
 	/* Store current stack pointer. */
 	movl %esp, %esi
 
+	/* Store EAX and EBX */
+
+	movl %eax,loader_eax
+	movl %ebx,loader_ebx
+
 	/* Setup new stack. */
 	movl $_stack, %ebx
 
diff --git a/payloads/libpayload/i386/main.c b/payloads/libpayload/i386/main.c
index 25e4de46d7..48d6ef5495 100644
--- a/payloads/libpayload/i386/main.c
+++ b/payloads/libpayload/i386/main.c
@@ -29,13 +29,21 @@
 
 #include <libpayload.h>
 
+unsigned long loader_eax;  /**< The value of EAX passed from the loader */
+unsigned long loader_ebx;  /**< The value of EBX passed from the loader */
+
+unsigned int main_argc;    /**< The argc value to pass to main() */
+
+/** The argv value to pass to main() */
+char *main_argv[MAX_ARGC_COUNT];
+
 /**
  * This is our C entry function - set up the system
  * and jump into the payload entry point.
  */
 void start_main(void)
 {
-	extern int main(void);
+	extern int main(int argc, char **argv);
 
 	/* Set up the consoles. */
 	console_init();
@@ -52,7 +60,8 @@ void start_main(void)
 	 * Go to the entry point.
 	 * In the future we may care about the return value.
 	 */
-	(void) main();
+
+	(void) main(main_argc, (main_argc != 0) ? main_argv : NULL);
 
 	/*
 	 * Returning here will go to the _leave function to return
diff --git a/payloads/libpayload/i386/multiboot.c b/payloads/libpayload/i386/multiboot.c
new file mode 100644
index 0000000000..09e72c768b
--- /dev/null
+++ b/payloads/libpayload/i386/multiboot.c
@@ -0,0 +1,96 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2008 Advanced Micro Devices, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <config.h>
+#include <libpayload.h>
+#include <multiboot_tables.h>
+
+extern unsigned long loader_eax;
+extern unsigned long loader_ebx;
+
+static void mb_parse_mmap(struct multiboot_header *table,
+			struct sysinfo_t *info)
+{
+	u8 *start = (u8 *) phys_to_virt(table->mmap_addr);
+	u8 *ptr = start;
+
+	info->n_memranges = 0;
+
+	while(ptr < (start + table->mmap_length)) {
+		struct multiboot_mmap *mmap = (struct multiboot_mmap *) ptr;
+
+		/* 1 == normal RAM.  Ignore everything else for now */
+
+		if (mmap->type == 1) {
+			info->memrange[info->n_memranges].base = mmap->addr;
+			info->memrange[info->n_memranges].size = mmap->length;
+
+			if (++info->n_memranges == SYSINFO_MAX_MEM_RANGES)
+				return;
+		}
+
+		ptr += (mmap->size + sizeof(mmap->size));
+	}
+}
+
+static void mb_parse_cmdline(struct multiboot_header *table)
+{
+	extern int main_argc;
+	extern char *main_argv[];
+	char *c = phys_to_virt(table->cmdline);
+
+	while(*c != '\0' && main_argc < MAX_ARGC_COUNT) {
+		main_argv[main_argc++] = c;
+
+		for( ; *c != '\0' && !isspace(*c); c++);
+
+		if (*c) {
+			*c = 0;
+			c++;
+		}
+	}
+}
+
+int get_multiboot_info(struct sysinfo_t *info)
+{
+	struct multiboot_header *table;
+
+	if (loader_eax != MULTIBOOT_MAGIC)
+		return -1;
+
+	table = (struct multiboot_header *) phys_to_virt(loader_ebx);
+
+	if (table->flags & MULTIBOOT_FLAGS_MMAP)
+		mb_parse_mmap(table, info);
+
+	if (table->flags & MULTIBOOT_FLAGS_CMDLINE)
+		mb_parse_cmdline(table);
+
+	return 0;
+}
diff --git a/payloads/libpayload/i386/sysinfo.c b/payloads/libpayload/i386/sysinfo.c
index a845a2817b..a074361f4f 100644
--- a/payloads/libpayload/i386/sysinfo.c
+++ b/payloads/libpayload/i386/sysinfo.c
@@ -29,6 +29,7 @@
 
 #include <config.h>
 #include <libpayload.h>
+#include <multiboot_tables.h>
 
 /**
  * This is a global structure that is used through the library - we set it
@@ -48,7 +49,15 @@ void lib_get_sysinfo(void)
 	/* Get the CPU speed (for delays). */
 	lib_sysinfo.cpu_khz = get_cpu_speed();
 
-	/* Get the memory information. */
+#ifdef CONFIG_MULTIBOOT
+	/* Get the information from the multiboot tables,
+	 * if they exist */
+	get_multiboot_info(&lib_sysinfo);
+#endif
+
+	/* Get information from the coreboot tables,
+	 * if they exist */
+
 	get_coreboot_info(&lib_sysinfo);
 
 	if (!lib_sysinfo.n_memranges) {