HV: init mmap info with multiboot2

Initialize mmap info of acrn mbi when boot from multiboot2 protocol,
with this patch acrn hv could boot from multiboot2;

Tracked-On: #4419

Signed-off-by: Victor Sun <victor.sun@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>

Author: jsun26intel

hypervisor/Makefile

@@ -197,6 +197,9 @@ BOOT_S_SRCS += arch/x86/boot/cpu_primary.S
 BOOT_S_SRCS += arch/x86/boot/cpu_save_boot_ctx.S
 BOOT_S_SRCS += arch/x86/boot/trampoline.S
 BOOT_C_SRCS += boot/multiboot.c
+ifeq ($(CONFIG_MULTIBOOT2),y)
+BOOT_C_SRCS += boot/multiboot2.c
+endif
 BOOT_C_SRCS += boot/reloc.c
 
 # hardware management component

hypervisor/boot/include/boot.h

@@ -8,6 +8,9 @@
 #define BOOT_H_
 
 #include <multiboot.h>
+#ifdef CONFIG_MULTIBOOT2
+#include <multiboot2.h>
+#endif
 #include <e820.h>
 
 #define MAX_BOOTARGS_SIZE		2048U
@@ -37,6 +40,15 @@ static inline bool boot_from_multiboot1(void)
 	return ((boot_regs[0] == MULTIBOOT_INFO_MAGIC) && (boot_regs[1] != 0U));
 }
 
+#ifdef CONFIG_MULTIBOOT2
+static inline bool boot_from_multiboot2(void)
+{
+	return ((boot_regs[0] == MULTIBOOT2_INFO_MAGIC) && (boot_regs[1] != 0U));
+}
+
+int32_t multiboot2_to_acrn_mbi(struct acrn_multiboot_info *mbi, void *mb2_info);
+#endif
+
 struct acrn_multiboot_info *get_multiboot_info(void);
 int32_t sanitize_multiboot_info(void);
 void parse_hv_cmdline(void);

hypervisor/boot/multiboot.c

@@ -54,7 +54,10 @@ int32_t sanitize_multiboot_info(void)
 		} else {
 			acrn_mbi.mi_flags &= ~MULTIBOOT_INFO_HAS_MODS;
 		}
-
+#ifdef CONFIG_MULTIBOOT2
+	} else if (boot_from_multiboot2()) {
+		ret = multiboot2_to_acrn_mbi(&acrn_mbi, hpa2hva_early((uint64_t)boot_regs[1]));
+#endif
 	} else {
 		pr_err("no multiboot info found!");
 		ret = -ENODEV;

hypervisor/boot/multiboot2.c

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2020 Intel Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <types.h>
+#include <errno.h>
+#include <boot.h>
+#include <pgtable.h>
+#include <util.h>
+#include <logmsg.h>
+
+/**
+ * @pre mbi != NULL && mb2_tag_mmap != NULL
+ */
+static void mb2_mmap_to_mbi(struct acrn_multiboot_info *mbi, struct multiboot2_tag_mmap *mb2_tag_mmap)
+{
+	uint32_t i;
+
+	/* multiboot2 mmap tag header occupied 16 bytes */
+	mbi->mi_mmap_entries = (mb2_tag_mmap->size - 16U) / sizeof(struct multiboot2_mmap_entry);
+	if (mbi->mi_mmap_entries > E820_MAX_ENTRIES) {
+		pr_err("Too many E820 entries %d\n", mbi->mi_mmap_entries);
+		mbi->mi_mmap_entries = E820_MAX_ENTRIES;
+	}
+	for (i = 0U; i < mbi->mi_mmap_entries; i++) {
+		mbi->mi_mmap_entry[i].baseaddr = mb2_tag_mmap->entries[i].addr;
+		mbi->mi_mmap_entry[i].length = mb2_tag_mmap->entries[i].len;
+		mbi->mi_mmap_entry[i].type = mb2_tag_mmap->entries[i].type;
+	}
+	mbi->mi_flags |= MULTIBOOT_INFO_HAS_MMAP;
+}
+
+/**
+ * @pre mbi != NULL && mb2_info != NULL
+ */
+int32_t multiboot2_to_acrn_mbi(struct acrn_multiboot_info *mbi, void *mb2_info)
+{
+	int32_t ret = 0;
+	struct multiboot2_tag *mb2_tag, *mb2_tag_end;
+	uint32_t mb2_info_size = *(uint32_t *)mb2_info;
+
+	/* The start part of multiboot2 info: total mbi size (4 bytes), reserved (4 bytes) */
+	mb2_tag = (struct multiboot2_tag *)((uint8_t *)mb2_info + 8U);
+	mb2_tag_end = (struct multiboot2_tag *)((uint8_t *)mb2_info + mb2_info_size);
+
+	while ((mb2_tag->type != MULTIBOOT2_TAG_TYPE_END) && (mb2_tag < mb2_tag_end)) {
+		if (mb2_tag->size == 0U) {
+			pr_err("the multiboot2 tag size should not be 0!");
+			ret = -EINVAL;
+			break;
+		}
+
+		switch (mb2_tag->type) {
+		case MULTIBOOT2_TAG_TYPE_MMAP:
+			mb2_mmap_to_mbi(mbi, (struct multiboot2_tag_mmap *)mb2_tag);
+			break;
+		default:
+			if (mb2_tag->type <= MULTIBOOT2_TAG_TYPE_LOAD_BASE_ADDR) {
+				pr_warn("unhandled multiboot2 tag type: %d", mb2_tag->type);
+			} else {
+				pr_err("unknown multiboot2 tag type: %d", mb2_tag->type);
+				ret = -EINVAL;
+			}
+			break;
+		}
+		if (ret != 0) {
+			pr_err("multiboot2 info format error!");
+			break;
+		}
+		/*
+		 * tag->size is not including padding whearas each tag
+		 * start at 8-bytes aligned address.
+		 */
+		mb2_tag = (struct multiboot2_tag *)((uint8_t *)mb2_tag
+				+ ((mb2_tag->size + (MULTIBOOT2_INFO_ALIGN - 1U)) & ~(MULTIBOOT2_INFO_ALIGN - 1U)));
+	}
+	return ret;
+}