payloads/libpayload/arch/arm64/main.c

/*
 * 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 <exception.h>
#include <libpayload.h>
#include <arch/mmu.h>

unsigned int main_argc;    /**< The argc value to pass to main() */

/** The argv value to pass to main() */
char *main_argv[MAX_ARGC_COUNT];

unsigned int test_exc;

static int test_exception(void)
{
	uint64_t *a = (uint64_t *)0xfffffffff0000000ULL;

	test_exc = 1;

	printf("%llx\n", *a);

	return 0;
}

/*
 * Func: pre_sysinfo_scan_mmu_setup
 * Desc: We need to setup and enable MMU before we can go to scan coreboot
 * tables. However, we are not sure what all memory regions to map. Thus,
 * initializing minimum required memory ranges
 */
static void pre_sysinfo_scan_mmu_setup(void)
{
	uint64_t start = (uint64_t)&_start;
	uint64_t end = (uint64_t)&_end;

	/* Memory range 1: Covers the area occupied by payload */
	mmu_presysinfo_memory_used(start, end - start);

	/*
	 * Memory range 2: Coreboot tables
	 *
	 * Maximum size is assumed 2 pages in case it crosses the GRANULE_SIZE
	 * boundary
	 */
	mmu_presysinfo_memory_used((uint64_t)get_cb_header_ptr(),
				   2 * GRANULE_SIZE);

	mmu_presysinfo_enable();
}

/*
 * Func: post_sysinfo_scan_mmu_setup
 * Desc: Once we have scanned coreboot tables, we have complete information
 * about different memory ranges. Thus, we can perform a complete mmu
 * initialization. Also, this takes care of DMA area setup
 */
static void post_sysinfo_scan_mmu_setup(void)
{
	struct memrange *ranges;
	uint64_t nranges;
	struct mmu_ranges mmu_ranges;
	struct mmu_memrange *dma_range;

	/* Get memrange info from lib_sysinfo */
	lib_sysinfo_get_memranges(&ranges, &nranges);

	/* Get memory ranges for mmu init from lib_sysinfo memrange */
	dma_range = mmu_init_ranges_from_sysinfo(ranges, nranges, &mmu_ranges);

	/* Disable mmu */
	mmu_disable();

	/* Init mmu */
	mmu_init(&mmu_ranges);

	/* Enable mmu */
	mmu_enable();

	/* Init dma memory */
	init_dma_memory((void *)dma_range->base, dma_range->size);
}

/**
 * This is our C entry function - set up the system
 * and jump into the payload entry point.
 */
void start_main(void);
void start_main(void)
{
	extern int main(int argc, char **argv);

	pre_sysinfo_scan_mmu_setup();

	/* Gather system information. */
	lib_get_sysinfo();

	post_sysinfo_scan_mmu_setup();

#if !IS_ENABLED(CONFIG_LP_SKIP_CONSOLE_INIT)
	console_init();
#endif

	printf("ARM64: Libpayload %s\n",__func__);
	exception_init();

	test_exception();
	/*
	 * Any other system init that has to happen before the
	 * user gets control goes here.
	 */

	/*
	 * Go to the entry point.
	 * In the future we may care about the return value.
	 */

	(void) main(main_argc, (main_argc != 0) ? main_argv : NULL);

	/*
	 * Returning here will go to the _leave function to return
	 * us to the original context.
	 */
}