1 files changed, 117 insertions, 0 deletions
diff --git a/src/arch/i386/boot/multiboot.c b/src/arch/i386/boot/multiboot.c
new file mode 100644
index 0000000000..af9b625877
--- /dev/null
+++ b/src/arch/i386/boot/multiboot.c
@@ -0,0 +1,117 @@
+/*
+ * support for Multiboot payloads
+ *
+ * Copyright (C) 2008 Robert Millan
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <cpu/x86/multiboot.h>
+#include <string.h>
+#include <device/resource.h>
+#include <console/console.h>
+
+typedef unsigned long long u64;
+
+static struct multiboot_mmap_entry *mb_mem;
+struct multiboot_info *mbi;
+
+static struct {
+	u64 addr;
+	u64 len;
+} reserved_mem[2];
+
+static void build_mb_mem_range_nooverlap(u64 addr, u64 len)
+{
+	int i;
+	for (i = 0; i < sizeof(reserved_mem) / sizeof(reserved_mem[0]); i++) {
+		/* free region fully contained in reserved region, abort */
+		if (addr >= reserved_mem[i].addr && addr + len <= reserved_mem[i].addr + reserved_mem[i].len)
+			return;
+		/* reserved region splits free region */
+		if (addr < reserved_mem[i].addr && addr + len > reserved_mem[i].addr + reserved_mem[i].len) {
+			build_mb_mem_range_nooverlap(addr, reserved_mem[i].addr - addr);
+			build_mb_mem_range_nooverlap(reserved_mem[i].addr + reserved_mem[i].len, (addr + len) - (reserved_mem[i].addr + reserved_mem[i].len));
+			return;
+		}
+		/* left overlap */
+		if (addr < reserved_mem[i].addr + reserved_mem[i].len && addr + len > reserved_mem[i].addr + reserved_mem[i].len) {
+			len += addr;
+			addr = reserved_mem[i].addr + reserved_mem[i].len;
+			len -= addr;
+			/* len += addr - old_addr */
+			continue;
+		}
+		/* right overlap */
+		if (addr < reserved_mem[i].addr && addr + len > reserved_mem[i].addr) {
+			len = reserved_mem[i].addr - addr;
+			continue;
+		}
+		/* none of the above, just add it */
+	}
+
+	mb_mem->addr = addr;
+	mb_mem->len = len;
+	mb_mem->type = 1;
+	mb_mem->size = sizeof(*mb_mem) - sizeof(mb_mem->size);
+	mb_mem++;
+}
+
+static void build_mb_mem_range(void *gp, struct device *dev, struct resource *res)
+{
+	build_mb_mem_range_nooverlap(res->base, res->size);
+}
+
+#define ROUND(_r,_a) ((_r) + (((_a) - 1)) & ~((_a) - 1))
+
+unsigned long write_multiboot_info(
+	unsigned long low_table_start, unsigned long low_table_end,
+	unsigned long rom_table_start, unsigned long rom_table_end)
+{
+	struct multiboot_info *mbi;
+	int i;
+
+	mbi = rom_table_end;
+	memset(mbi, 0, sizeof(*mbi));
+	rom_table_end += sizeof(*mbi);
+
+	mbi->mmap_addr = (u32) rom_table_end;
+	mb_mem = rom_table_end;
+
+	/* reserved regions */
+	reserved_mem[0].addr = low_table_start;
+	reserved_mem[0].len = ROUND(low_table_end - low_table_start, 4096);
+	reserved_mem[1].addr = rom_table_start;
+	reserved_mem[1].len = ROUND(rom_table_end - rom_table_start, 4096);
+
+	for (i = 0; i < sizeof(reserved_mem) / sizeof(reserved_mem[0]); i++) {
+		mb_mem->addr = reserved_mem[i].addr;
+		mb_mem->len = reserved_mem[i].len;
+		mb_mem->type = 2;
+		mb_mem->size = sizeof(*mb_mem) - sizeof(mb_mem->size);
+		mb_mem++;
+	}
+
+	/* free regions */
+	search_global_resources( IORESOURCE_MEM | IORESOURCE_CACHEABLE,
+		IORESOURCE_MEM | IORESOURCE_CACHEABLE, build_mb_mem_range, NULL);
+
+	mbi->mmap_length = ((u32) mb_mem) - mbi->mmap_addr;
+	mbi->flags |= MB_INFO_MEM_MAP;
+
+	printk_info("Multiboot Information structure has been written.\n");
+
+	return mb_mem;
+}