plat/rpi3/rpi3_bl31_setup.c

/*
 * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <assert.h>
#include <bl_common.h>
#include <platform.h>
#include <platform_def.h>
#include <xlat_mmu_helpers.h>
#include <xlat_tables_defs.h>

#include "rpi3_private.h"

#define BL31_END	(uintptr_t)(&__BL31_END__)

/*
 * Placeholder variables for copying the arguments that have been passed to
 * BL31 from BL2.
 */
static entry_point_info_t bl32_image_ep_info;
static entry_point_info_t bl33_image_ep_info;

/*******************************************************************************
 * Return a pointer to the 'entry_point_info' structure of the next image for
 * the security state specified. BL33 corresponds to the non-secure image type
 * while BL32 corresponds to the secure image type. A NULL pointer is returned
 * if the image does not exist.
 ******************************************************************************/
entry_point_info_t *bl31_plat_get_next_image_ep_info(uint32_t type)
{
	entry_point_info_t *next_image_info;

	assert(sec_state_is_valid(type) != 0);

	next_image_info = (type == NON_SECURE)
			? &bl33_image_ep_info : &bl32_image_ep_info;

	/* None of the images can have 0x0 as the entrypoint. */
	if (next_image_info->pc) {
		return next_image_info;
	} else {
		return NULL;
	}
}

/*******************************************************************************
 * Perform any BL31 early platform setup. Here is an opportunity to copy
 * parameters passed by the calling EL (S-EL1 in BL2 & S-EL3 in BL1) before
 * they are lost (potentially). This needs to be done before the MMU is
 * initialized so that the memory layout can be used while creating page
 * tables. BL2 has flushed this information to memory, so we are guaranteed
 * to pick up good data.
 ******************************************************************************/
void bl31_early_platform_setup(void *from_bl2,
			       void *plat_params_from_bl2)
{
	/* Initialize the console to provide early debug support */
	rpi3_console_init();

	/*
	 * In debug builds, we pass a special value in 'plat_params_from_bl2'
	 * to verify platform parameters from BL2 to BL31.
	 * In release builds, it's not used.
	 */
	assert(((uintptr_t)plat_params_from_bl2) == RPI3_BL31_PLAT_PARAM_VAL);

	/*
	 * Check params passed from BL2 should not be NULL,
	 */
	bl_params_t *params_from_bl2 = (bl_params_t *)from_bl2;

	assert(params_from_bl2 != NULL);
	assert(params_from_bl2->h.type == PARAM_BL_PARAMS);
	assert(params_from_bl2->h.version >= VERSION_2);

	bl_params_node_t *bl_params = params_from_bl2->head;

	/*
	 * Copy BL33 and BL32 (if present), entry point information.
	 * They are stored in Secure RAM, in BL2's address space.
	 */
	while (bl_params) {
		if (bl_params->image_id == BL32_IMAGE_ID) {
			bl32_image_ep_info = *bl_params->ep_info;
		}

		if (bl_params->image_id == BL33_IMAGE_ID) {
			bl33_image_ep_info = *bl_params->ep_info;
		}

		bl_params = bl_params->next_params_info;
	}

	if (bl33_image_ep_info.pc == 0) {
		panic();
	}

#if RPI3_DIRECT_LINUX_BOOT
# if RPI3_BL33_IN_AARCH32
	/*
	 * According to the file ``Documentation/arm/Booting`` of the Linux
	 * kernel tree, Linux expects:
	 * r0 = 0
	 * r1 = machine type number, optional in DT-only platforms (~0 if so)
	 * r2 = Physical address of the device tree blob
	 */
	VERBOSE("rpi3: Preparing to boot 32-bit Linux kernel\n");
	bl33_image_ep_info.args.arg0 = 0U;
	bl33_image_ep_info.args.arg1 = ~0U;
	bl33_image_ep_info.args.arg2 = (u_register_t) RPI3_PRELOADED_DTB_BASE;
# else
	/*
	 * According to the file ``Documentation/arm64/booting.txt`` of the
	 * Linux kernel tree, Linux expects the physical address of the device
	 * tree blob (DTB) in x0, while x1-x3 are reserved for future use and
	 * must be 0.
	 */
	VERBOSE("rpi3: Preparing to boot 64-bit Linux kernel\n");
	bl33_image_ep_info.args.arg0 = (u_register_t) RPI3_PRELOADED_DTB_BASE;
	bl33_image_ep_info.args.arg1 = 0ULL;
	bl33_image_ep_info.args.arg2 = 0ULL;
	bl33_image_ep_info.args.arg3 = 0ULL;
# endif /* RPI3_BL33_IN_AARCH32 */
#endif /* RPI3_DIRECT_LINUX_BOOT */
}

void bl31_plat_arch_setup(void)
{
	rpi3_setup_page_tables(BL31_BASE, BL31_END - BL31_BASE,
			       BL_CODE_BASE, BL_CODE_END,
			       BL_RO_DATA_BASE, BL_RO_DATA_END
#if USE_COHERENT_MEM
			       , BL_COHERENT_RAM_BASE, BL_COHERENT_RAM_END
#endif
			      );

	enable_mmu_el3(0);
}

void bl31_platform_setup(void)
{
	/*
	 * Do initial security configuration to allow DRAM/device access
	 * (if earlier BL has not already done so).
	 */

	return;
}