acrn-hypervisor/hypervisor/boot/sbl/multiboot.c

/*
 * Copyright (C) 2018 Intel Corporation. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <hypervisor.h>
#include <multiboot.h>
#include <zeropage.h>
#include <hob_parse.h>

#define BOOT_ARGS_LOAD_ADDR				0x24EFC000

#define ACRN_DBG_BOOT	6

/* There are two sources for vm0 kernel cmdline:
 * - cmdline from sbl. mbi->cmdline
 * - cmdline from acrn stitching tool. mod[0].mm_string
 * We need to merge them together
 */
static char kernel_cmdline[MEM_2K];

/* now modules support: FIRMWARE & RAMDISK & SeedList */
static void parse_other_modules(struct vm *vm,
	struct multiboot_module *mods, int mods_count)
{
	int i = 0;

	for (i = 0; i < mods_count; i++) {
		int type_len = 0;
		const char *start = (const char *) (uint64_t)mods[i].mm_string;
		const char *end;
		void *mod_addr = (void *)(uint64_t)mods[i].mm_mod_start;
		uint32_t mod_size = mods[i].mm_mod_end - mods[i].mm_mod_start;

		dev_dbg(ACRN_DBG_BOOT, "other mod-%d start=0x%x, end=0x%x",
			i, mods[i].mm_mod_start, mods[i].mm_mod_end);
		dev_dbg(ACRN_DBG_BOOT, "cmd addr=0x%x, str=%s",
			mods[i].mm_string, start);

		while (*start == ' ')
			start++;

		end = start;
		while (*end != ' ' && (*end) != 0)
			end++;

		type_len = end - start;
		if (strncmp("FIRMWARE", start, type_len) == 0) {
			char  dyn_bootargs[100] = {0};
			void *load_addr = vm->sw.linux_info.bootargs_load_addr;
			uint32_t args_size = vm->sw.linux_info.bootargs_size;
			static int copy_once = 1;

			start = end + 1; /*it is fw name for boot args */
			snprintf(dyn_bootargs, 100, " %s=0x%x@0x%x ",
				start, mod_size, mod_addr);
			dev_dbg(ACRN_DBG_BOOT, "fw-%d: %s", i, dyn_bootargs);

			/*copy boot args to load addr, set src=load addr*/
			if (copy_once != 0) {
				copy_once = 0;
				strcpy_s(load_addr, MEM_2K,
					vm->sw.linux_info.bootargs_src_addr);
				vm->sw.linux_info.bootargs_src_addr = load_addr;
			}

			strcpy_s(load_addr + args_size,
				100, dyn_bootargs);
			vm->sw.linux_info.bootargs_size =
				strnlen_s(load_addr, MEM_2K);

		} else if (strncmp("RAMDISK", start, type_len) == 0) {
			vm->sw.linux_info.ramdisk_src_addr = mod_addr;
			vm->sw.linux_info.ramdisk_load_addr = mod_addr;
			vm->sw.linux_info.ramdisk_size = mod_size;
		} else if (strncmp("SeedList", start, type_len) == 0) {
			parse_seed_list(mod_addr);
		} else {
			pr_warn("not support mod, cmd: %s", start);
		}
	}
}

static void *get_kernel_load_addr(void *kernel_src_addr)
{
	struct zero_page *zeropage;

	/* According to the explaination for pref_address
	 * in Documentation/x86/boot.txt, a relocating
	 * bootloader should attempt to load kernel at pref_address
	 * if possible. A non-relocatable kernel will unconditionally
	 * move itself and to run at this address, so no need to copy
	 * kernel to perf_address by bootloader, if kernel is
	 * non-relocatable.
	 */
	zeropage = (struct zero_page *)kernel_src_addr;
	if (zeropage->hdr.relocatable_kernel != 0U)
		return (void *)zeropage->hdr.pref_addr;

	return kernel_src_addr;
}

int init_vm0_boot_info(struct vm *vm)
{
	struct multiboot_module *mods = NULL;
	struct multiboot_info *mbi = NULL;

	if (!is_vm0(vm)) {
		pr_err("just for vm0 to get info!");
		return -EINVAL;
	}

	if (boot_regs[0] != MULTIBOOT_INFO_MAGIC) {
		ASSERT(false, "no multiboot info found");
		return -EINVAL;
	}

	mbi = (struct multiboot_info *)((uint64_t)boot_regs[1]);

	dev_dbg(ACRN_DBG_BOOT, "Multiboot detected, flag=0x%x", mbi->mi_flags);
	if ((mbi->mi_flags & MULTIBOOT_INFO_HAS_MODS) == 0U) {
		ASSERT(false, "no sos kernel info found");
		return -EINVAL;
	}

	dev_dbg(ACRN_DBG_BOOT, "mod counts=%d\n", mbi->mi_mods_count);

	/* mod[0] is for kernel&cmdline, other mod for ramdisk/firmware info*/
	mods = (struct multiboot_module *)(uint64_t)mbi->mi_mods_addr;

	dev_dbg(ACRN_DBG_BOOT, "mod0 start=0x%x, end=0x%x",
		mods[0].mm_mod_start, mods[0].mm_mod_end);
	dev_dbg(ACRN_DBG_BOOT, "cmd addr=0x%x, str=%s", mods[0].mm_string,
		(char *) (uint64_t)mods[0].mm_string);

	vm->sw.kernel_type = VM_LINUX_GUEST;
	vm->sw.kernel_info.kernel_src_addr =
		(void *)(uint64_t)mods[0].mm_mod_start;
	vm->sw.kernel_info.kernel_size =
		mods[0].mm_mod_end - mods[0].mm_mod_start;
	vm->sw.kernel_info.kernel_load_addr =
		get_kernel_load_addr(vm->sw.kernel_info.kernel_src_addr);


	/*
	 * If there is cmdline from mbi->mi_cmdline, merge it with
	 * mods[0].mm_string
	 */
	if ((mbi->mi_flags & MULTIBOOT_INFO_HAS_CMDLINE) != 0U) {
		char *cmd_src, *cmd_dst;
		int off = 0;

		cmd_dst = kernel_cmdline;
		cmd_src = HPA2HVA((uint64_t)mbi->mi_cmdline);
		strncpy_s(cmd_dst, MEM_2K, cmd_src, strnlen_s(cmd_src, MEM_2K));
		off = strnlen_s(cmd_dst, MEM_2K);
		cmd_dst[off] = ' ';	/* insert space */
		off += 1;

		cmd_dst += off;
		cmd_src = HPA2HVA((uint64_t)mods[0].mm_string);
		strncpy_s(cmd_dst, MEM_2K - off, cmd_src,
				strnlen_s(cmd_src, MEM_2K - off));

		vm->sw.linux_info.bootargs_src_addr = kernel_cmdline;
		vm->sw.linux_info.bootargs_size =
			strnlen_s(kernel_cmdline, MEM_2K);
	} else {
		vm->sw.linux_info.bootargs_src_addr =
			(void *)(uint64_t)mods[0].mm_string;
		vm->sw.linux_info.bootargs_size =
			strnlen_s((char *)(uint64_t) mods[0].mm_string, MEM_2K);
	}

	vm->sw.linux_info.bootargs_load_addr = (void *)BOOT_ARGS_LOAD_ADDR;

	if (mbi->mi_mods_count > 1) {
		/*parse other modules, like firmware /ramdisk */
		parse_other_modules(vm, mods + 1, mbi->mi_mods_count - 1);
	}
	return 0;
}