• Alexei Fedorov's avatar
    Refactor ARMv8.3 Pointer Authentication support code · ed108b56
    Alexei Fedorov authored
    
    This patch provides the following features and makes modifications
    listed below:
    - Individual APIAKey key generation for each CPU.
    - New key generation on every BL31 warm boot and TSP CPU On event.
    - Per-CPU storage of APIAKey added in percpu_data[]
      of cpu_data structure.
    - `plat_init_apiakey()` function replaced with `plat_init_apkey()`
      which returns 128-bit value and uses Generic timer physical counter
      value to increase the randomness of the generated key.
      The new function can be used for generation of all ARMv8.3-PAuth keys
    - ARMv8.3-PAuth specific code placed in `lib\extensions\pauth`.
    - New `pauth_init_enable_el1()` and `pauth_init_enable_el3()` functions
      generate, program and enable APIAKey_EL1 for EL1 and EL3 respectively;
      pauth_disable_el1()` and `pauth_disable_el3()` functions disable
      PAuth for EL1 and EL3 respectively;
      `pauth_load_bl31_apiakey()` loads saved per-CPU APIAKey_EL1 from
      cpu-data structure.
    - Combined `save_gp_pauth_registers()` function replaces calls to
      `save_gp_registers()` and `pauth_context_save()`;
      `restore_gp_pauth_registers()` replaces `pauth_context_restore()`
      and `restore_gp_registers()` calls.
    - `restore_gp_registers_eret()` function removed with corresponding
      code placed in `el3_exit()`.
    - Fixed the issue when `pauth_t pauth_ctx` structure allocated space
      for 12 uint64_t PAuth registers instead of 10 by removal of macro
      CTX_PACGAKEY_END from `include/lib/el3_runtime/aarch64/context.h`
      and assigning its value to CTX_PAUTH_REGS_END.
    - Use of MODE_SP_ELX and MODE_SP_EL0 macro definitions
      in `msr	spsel`  instruction instead of hard-coded values.
    - Changes in documentation related to ARMv8.3-PAuth and ARMv8.5-BTI.
    
    Change-Id: Id18b81cc46f52a783a7e6a09b9f149b6ce803211
    Signed-off-by: default avatarAlexei Fedorov <Alexei.Fedorov@arm.com>
    ed108b56
bl1_entrypoint.S 2.17 KB
/*
 * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <arch.h>
#include <el3_common_macros.S>

	.globl	bl1_entrypoint


	/* -----------------------------------------------------
	 * bl1_entrypoint() is the entry point into the trusted
	 * firmware code when a cpu is released from warm or
	 * cold reset.
	 * -----------------------------------------------------
	 */

func bl1_entrypoint
	/* ---------------------------------------------------------------------
	 * If the reset address is programmable then bl1_entrypoint() is
	 * executed only on the cold boot path. Therefore, we can skip the warm
	 * boot mailbox mechanism.
	 * ---------------------------------------------------------------------
	 */
	el3_entrypoint_common					\
		_init_sctlr=1					\
		_warm_boot_mailbox=!PROGRAMMABLE_RESET_ADDRESS	\
		_secondary_cold_boot=!COLD_BOOT_SINGLE_CPU	\
		_init_memory=1					\
		_init_c_runtime=1				\
		_exception_vectors=bl1_exceptions

	/* --------------------------------------------------------------------
	 * Perform BL1 setup
	 * --------------------------------------------------------------------
	 */
	bl	bl1_setup

#if ENABLE_PAUTH
	/* --------------------------------------------------------------------
	 * Program APIAKey_EL1 and enable pointer authentication.
	 * --------------------------------------------------------------------
	 */
	bl	pauth_init_enable_el3
#endif /* ENABLE_PAUTH */

	/* --------------------------------------------------------------------
	 * Initialize platform and jump to our c-entry point
	 * for this type of reset.
	 * --------------------------------------------------------------------
	 */
	bl	bl1_main

#if ENABLE_PAUTH
	/* --------------------------------------------------------------------
	 * Disable pointer authentication before jumping to next boot image.
	 * --------------------------------------------------------------------
	 */
	bl	pauth_disable_el3
#endif /* ENABLE_PAUTH */

	/* --------------------------------------------------
	 * Do the transition to next boot image.
	 * --------------------------------------------------
	 */
	b	el3_exit
endfunc bl1_entrypoint