arch/microblaze/lib/bootm.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2007 Michal Simek
 * (C) Copyright 2004 Atmark Techno, Inc.
 *
 * Michal  SIMEK <monstr@monstr.eu>
 * Yasushi SHOJI <yashi@atmark-techno.com>
 */

#include <common.h>
#include <command.h>
#include <env.h>
#include <fdt_support.h>
#include <image.h>
#include <u-boot/zlib.h>
#include <asm/byteorder.h>

DECLARE_GLOBAL_DATA_PTR;

static ulong get_sp(void)
{
	ulong ret;

	asm("addik %0, r1, 0" : "=r"(ret) : );
	return ret;
}

void arch_lmb_reserve(struct lmb *lmb)
{
	ulong sp, bank_end;
	int bank;

	/*
	 * Booting a (Linux) kernel image
	 *
	 * Allocate space for command line and board info - the
	 * address should be as high as possible within the reach of
	 * the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
	 * memory, which means far enough below the current stack
	 * pointer.
	 */
	sp = get_sp();
	debug("## Current stack ends at 0x%08lx ", sp);

	/* adjust sp by 4K to be safe */
	sp -= 4096;
	for (bank = 0; bank < CONFIG_NR_DRAM_BANKS; bank++) {
		if (sp < gd->bd->bi_dram[bank].start)
			continue;
		bank_end = gd->bd->bi_dram[bank].start +
			gd->bd->bi_dram[bank].size;
		if (sp >= bank_end)
			continue;
		lmb_reserve(lmb, sp, bank_end - sp);
		break;
	}
}

int do_bootm_linux(int flag, int argc, char * const argv[],
		   bootm_headers_t *images)
{
	/* First parameter is mapped to $r5 for kernel boot args */
	void	(*thekernel) (char *, ulong, ulong);
	char	*commandline = env_get("bootargs");
	ulong	rd_data_start, rd_data_end;

	/*
	 * allow the PREP bootm subcommand, it is required for bootm to work
	 */
	if (flag & BOOTM_STATE_OS_PREP)
		return 0;

	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
		return 1;

	int	ret;

	char	*of_flat_tree = NULL;
#if defined(CONFIG_OF_LIBFDT)
	/* did generic code already find a device tree? */
	if (images->ft_len)
		of_flat_tree = images->ft_addr;
#endif

	thekernel = (void (*)(char *, ulong, ulong))images->ep;

	/* find ramdisk */
	ret = boot_get_ramdisk(argc, argv, images, IH_ARCH_MICROBLAZE,
			&rd_data_start, &rd_data_end);
	if (ret)
		return 1;

	bootstage_mark(BOOTSTAGE_ID_RUN_OS);

	if (!of_flat_tree && argc > 1)
		of_flat_tree = (char *)simple_strtoul(argv[1], NULL, 16);

	/* fixup the initrd now that we know where it should be */
	if (images->rd_start && images->rd_end && of_flat_tree) {
		ret = fdt_initrd(of_flat_tree, images->rd_start,
				 images->rd_end);
		if (ret)
			return 1;
	}

#ifdef DEBUG
	printf("## Transferring control to Linux (at address 0x%08lx) ",
	       (ulong)thekernel);
	printf("ramdisk 0x%08lx, FDT 0x%08lx...\n",
	       rd_data_start, (ulong) of_flat_tree);
#endif

#ifdef XILINX_USE_DCACHE
	flush_cache(0, XILINX_DCACHE_BYTE_SIZE);
#endif
	/*
	 * Linux Kernel Parameters (passing device tree):
	 * r5: pointer to command line
	 * r6: pointer to ramdisk
	 * r7: pointer to the fdt, followed by the board info data
	 */
	thekernel(commandline, rd_data_start, (ulong)of_flat_tree);
	/* does not return */

	return 1;
}