• Juan Castillo's avatar
    Add optional platform error handler API · 40fc6cd1
    Juan Castillo authored
    This patch adds an optional API to the platform port:
    
        void plat_error_handler(int err) __dead2;
    
    The platform error handler is called when there is a specific error
    condition after which Trusted Firmware cannot continue. While panic()
    simply prints the crash report (if enabled) and spins, the platform
    error handler can be used to hand control over to the platform port
    so it can perform specific bookeeping or post-error actions (for
    example, reset the system). This function must not return.
    
    The parameter indicates the type of error using standard codes from
    errno.h. Possible errors reported by the generic code are:
    
        -EAUTH  : a certificate or image could not be authenticated
                  (when Trusted Board Boot is enabled)
        -ENOENT : the requested image or certificate could not be found
                  or an IO error was detected
        -ENOMEM : resources exhausted. Trusted Firmware does not use
                  dynamic memory, so this error is usually an indication
                  of an incorrect array size
    
    A default weak implementation of this function has been provided.
    It simply implements an infinite loop.
    
    Change-Id: Iffaf9eee82d037da6caa43b3aed51df555e597a3
    40fc6cd1
bl1_main.c 7.62 KB
/*
 * Copyright (c) 2013-2015, ARM Limited and Contributors. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 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.
 *
 * Neither the name of ARM nor the names of its contributors may be used
 * to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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 <arch.h>
#include <arch_helpers.h>
#include <assert.h>
#include <auth_mod.h>
#include <bl_common.h>
#include <debug.h>
#include <platform.h>
#include <platform_def.h>
#include "bl1_private.h"

/*******************************************************************************
 * Runs BL2 from the given entry point. It results in dropping the
 * exception level
 ******************************************************************************/
static void __dead2 bl1_run_bl2(entry_point_info_t *bl2_ep)
{
	/* Check bl2 security state is expected as secure */
	assert(GET_SECURITY_STATE(bl2_ep->h.attr) == SECURE);
	/* Check NS Bit is also set as secure */
	assert(!(read_scr_el3() & SCR_NS_BIT));

	bl1_arch_next_el_setup();

	/* Tell next EL what we want done */
	bl2_ep->args.arg0 = RUN_IMAGE;

	write_spsr_el3(bl2_ep->spsr);
	write_elr_el3(bl2_ep->pc);

	eret(bl2_ep->args.arg0,
		bl2_ep->args.arg1,
		bl2_ep->args.arg2,
		bl2_ep->args.arg3,
		bl2_ep->args.arg4,
		bl2_ep->args.arg5,
		bl2_ep->args.arg6,
		bl2_ep->args.arg7);
}

/*******************************************************************************
 * The next function has a weak definition. Platform specific code can override
 * it if it wishes to.
 ******************************************************************************/
#pragma weak bl1_init_bl2_mem_layout

/*******************************************************************************
 * Function that takes a memory layout into which BL2 has been loaded and
 * populates a new memory layout for BL2 that ensures that BL1's data sections
 * resident in secure RAM are not visible to BL2.
 ******************************************************************************/
void bl1_init_bl2_mem_layout(const meminfo_t *bl1_mem_layout,
			     meminfo_t *bl2_mem_layout)
{
	const size_t bl1_size = BL1_RAM_LIMIT - BL1_RAM_BASE;

	assert(bl1_mem_layout != NULL);
	assert(bl2_mem_layout != NULL);

	/* Check that BL1's memory is lying outside of the free memory */
	assert((BL1_RAM_LIMIT <= bl1_mem_layout->free_base) ||
	       (BL1_RAM_BASE >= bl1_mem_layout->free_base + bl1_mem_layout->free_size));

	/* Remove BL1 RW data from the scope of memory visible to BL2 */
	*bl2_mem_layout = *bl1_mem_layout;
	reserve_mem(&bl2_mem_layout->total_base,
		    &bl2_mem_layout->total_size,
		    BL1_RAM_BASE,
		    bl1_size);

	flush_dcache_range((unsigned long)bl2_mem_layout, sizeof(meminfo_t));
}

/*******************************************************************************
 * Function to perform late architectural and platform specific initialization.
 * It also locates and loads the BL2 raw binary image in the trusted DRAM. Only
 * called by the primary cpu after a cold boot.
 * TODO: Add support for alternative image load mechanism e.g using virtio/elf
 * loader etc.
  ******************************************************************************/
void bl1_main(void)
{
	/* Announce our arrival */
	NOTICE(FIRMWARE_WELCOME_STR);
	NOTICE("BL1: %s\n", version_string);
	NOTICE("BL1: %s\n", build_message);

	INFO("BL1: RAM 0x%lx - 0x%lx\n", BL1_RAM_BASE, BL1_RAM_LIMIT);

	image_info_t bl2_image_info = { {0} };
	entry_point_info_t bl2_ep = { {0} };
	meminfo_t *bl1_tzram_layout;
	meminfo_t *bl2_tzram_layout = 0x0;
	int err;

#if DEBUG
	unsigned long val;
	/*
	 * Ensure that MMU/Caches and coherency are turned on
	 */
	val = read_sctlr_el3();
	assert(val & SCTLR_M_BIT);
	assert(val & SCTLR_C_BIT);
	assert(val & SCTLR_I_BIT);
	/*
	 * Check that Cache Writeback Granule (CWG) in CTR_EL0 matches the
	 * provided platform value
	 */
	val = (read_ctr_el0() >> CTR_CWG_SHIFT) & CTR_CWG_MASK;
	/*
	 * If CWG is zero, then no CWG information is available but we can
	 * at least check the platform value is less than the architectural
	 * maximum.
	 */
	if (val != 0)
		assert(CACHE_WRITEBACK_GRANULE == SIZE_FROM_LOG2_WORDS(val));
	else
		assert(CACHE_WRITEBACK_GRANULE <= MAX_CACHE_LINE_SIZE);
#endif

	/* Perform remaining generic architectural setup from EL3 */
	bl1_arch_setup();

	/* Perform platform setup in BL1. */
	bl1_platform_setup();

	SET_PARAM_HEAD(&bl2_image_info, PARAM_IMAGE_BINARY, VERSION_1, 0);
	SET_PARAM_HEAD(&bl2_ep, PARAM_EP, VERSION_1, 0);

	/* Find out how much free trusted ram remains after BL1 load */
	bl1_tzram_layout = bl1_plat_sec_mem_layout();

	INFO("BL1: Loading BL2\n");

#if TRUSTED_BOARD_BOOT
	/* Initialize authentication module */
	auth_mod_init();
#endif /* TRUSTED_BOARD_BOOT */

	/* Load the BL2 image */
	err = load_auth_image(bl1_tzram_layout,
			 BL2_IMAGE_ID,
			 BL2_BASE,
			 &bl2_image_info,
			 &bl2_ep);

	if (err) {
		ERROR("Failed to load BL2 firmware.\n");
		plat_error_handler(err);
	}

	/*
	 * Create a new layout of memory for BL2 as seen by BL1 i.e.
	 * tell it the amount of total and free memory available.
	 * This layout is created at the first free address visible
	 * to BL2. BL2 will read the memory layout before using its
	 * memory for other purposes.
	 */
	bl2_tzram_layout = (meminfo_t *) bl1_tzram_layout->free_base;
	bl1_init_bl2_mem_layout(bl1_tzram_layout, bl2_tzram_layout);

	bl1_plat_set_bl2_ep_info(&bl2_image_info, &bl2_ep);
	bl2_ep.args.arg1 = (unsigned long)bl2_tzram_layout;
	NOTICE("BL1: Booting BL2\n");
	INFO("BL1: BL2 address = 0x%llx\n",
		(unsigned long long) bl2_ep.pc);
	INFO("BL1: BL2 spsr = 0x%x\n", bl2_ep.spsr);
	VERBOSE("BL1: BL2 memory layout address = 0x%llx\n",
		(unsigned long long) bl2_tzram_layout);

	bl1_run_bl2(&bl2_ep);

	return;
}

/*******************************************************************************
 * Temporary function to print the fact that BL2 has done its job and BL31 is
 * about to be loaded. This is needed as long as printfs cannot be used
 ******************************************************************************/
void display_boot_progress(entry_point_info_t *bl31_ep_info)
{
	NOTICE("BL1: Booting BL3-1\n");
	INFO("BL1: BL3-1 address = 0x%llx\n",
		(unsigned long long)bl31_ep_info->pc);
	INFO("BL1: BL3-1 spsr = 0x%llx\n",
		(unsigned long long)bl31_ep_info->spsr);
	INFO("BL1: BL3-1 params address = 0x%llx\n",
		(unsigned long long)bl31_ep_info->args.arg0);
	INFO("BL1: BL3-1 plat params address = 0x%llx\n",
		(unsigned long long)bl31_ep_info->args.arg1);
}