GNUBoot/coreboot-kgpe-d16
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity
coreboot-kgpe-d16/src/arch/arm64/transition.c

78 lines
2.1 KiB
C
Raw Normal View History

src/arch/arm64: Convert to SPDX license header This also drops individual copyright notices, all mentioned authors in that part of the tree are already listed in AUTHORS. Change-Id: Ic5eddc961d015328e5a90994b7963e7af83cddd3 Signed-off-by: Patrick Georgi <pgeorgi@google.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/39279 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: HAOUAS Elyes <ehaouas@noos.fr> Reviewed-by: Angel Pons <th3fanbus@gmail.com>
2020-03-04 14:39:09 +01:00
/* SPDX-License-Identifier: GPL-2.0-only */
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
arm64: tegra132: tegra210: Remove old arm64/stage_entry.S This patch removes the old arm64/stage_entry.S code that was too specific to the Tegra SoC boot flow, and replaces it with code that hides the peculiarities of switching to a different CPU/arch in ramstage in the Tegra SoC directories. BRANCH=None BUG=None TEST=Built Ryu and Smaug. !!!UNTESTED!!! Change-Id: Ib3a0448b30ac9c7132581464573efd5e86e03698 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/12078 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2015-10-16 22:10:02 +02:00
#include <arch/cache.h>
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
#include <arch/lib_helpers.h>
arm64: Disable MMU during legacy payload handoff (without Arm TF) coreboot payloads expect to be entered with MMU disabled on arm64. The usual path via Arm TF already does this, so let's align the legacy path (without Secure Monitor) to do the same. Change-Id: I18717e00c905123d53b27a81185b534ba819c7b3 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27878 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:07:51 +02:00
#include <arch/mmu.h>
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
#include <arch/transition.h>
arm64: tegra132: tegra210: Remove old arm64/stage_entry.S This patch removes the old arm64/stage_entry.S code that was too specific to the Tegra SoC boot flow, and replaces it with code that hides the peculiarities of switching to a different CPU/arch in ramstage in the Tegra SoC directories. BRANCH=None BUG=None TEST=Built Ryu and Smaug. !!!UNTESTED!!! Change-Id: Ib3a0448b30ac9c7132581464573efd5e86e03698 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/12078 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2015-10-16 22:10:02 +02:00
#include <assert.h>
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
compiler.h: add __weak macro Instead of writing out '__attribute__((weak))' use a shorter form. Change-Id: If418a1d55052780077febd2d8f2089021f414b91 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: https://review.coreboot.org/25767 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-by: Justin TerAvest <teravest@chromium.org>
2018-04-21 22:45:32 +02:00
void __weak exc_dispatch(struct exc_state *exc_state, uint64_t id)
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
{
/* Default weak implementation does nothing. */
}
void exc_entry(struct exc_state *exc_state, uint64_t id)
{
struct elx_state *elx = &exc_state->elx;
struct regs *regs = &exc_state->regs;
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
uint8_t elx_mode;
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
elx->spsr = raw_read_spsr_el3();
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
elx_mode = get_mode_from_spsr(elx->spsr);
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
if (elx_mode == SPSR_USE_H)
regs->sp = (uint64_t)&exc_state[1];
else
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
regs->sp = raw_read_sp_el0();
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
elx->elr = raw_read_elr_el3();
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
exc_dispatch(exc_state, id);
}
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
void transition_to_el2(void *entry, void *arg, uint64_t spsr)
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
{
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
struct exc_state exc_state;
struct elx_state *elx = &exc_state.elx;
struct regs *regs = &exc_state.regs;
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
regs->x[X0_INDEX] = (uint64_t)arg;
elx->elr = (uint64_t)entry;
elx->spsr = spsr;
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
/*
* Policies enforced:
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
* 1. We support only transitions to EL2
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
* 2. We support transitions to Aarch64 mode only
*
* If any of the above conditions holds false, then we need a proper way
* to update SCR/HCR before removing the checks below
*/
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
assert(get_el_from_spsr(spsr) == EL2 && !(spsr & SPSR_ERET_32));
arm64: tegra132: tegra210: Remove old arm64/stage_entry.S This patch removes the old arm64/stage_entry.S code that was too specific to the Tegra SoC boot flow, and replaces it with code that hides the peculiarities of switching to a different CPU/arch in ramstage in the Tegra SoC directories. BRANCH=None BUG=None TEST=Built Ryu and Smaug. !!!UNTESTED!!! Change-Id: Ib3a0448b30ac9c7132581464573efd5e86e03698 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/12078 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2015-10-16 22:10:02 +02:00
arm64: Correctly unmask asynchronous SError interrupts Arm CPUs have always had an odd feature that allows you to mask not only true interrupts, but also "external aborts" (memory bus errors from outside the CPU). CPUs usually have all of these masked after reset, which we quickly learned was a bad idea back when bringing up the first arm32 systems in coreboot. Masking external aborts means that if any of your firmware code does an illegal memory access, you will only see it once the kernel comes up and unmasks the abort (not when it happens). Therefore, we always unmask everything in early bootblock assembly code. When arm64 came around, it had very similar masking bits and we did the same there, thinking the issue resolved. Unfortunately Arm, in their ceaseless struggle for more complexity, decided that having a single bit to control this masking behavior is no longer enough: on AArch64, in addition to the PSTATE.DAIF bits that are analogous to arm32's CPSR, there are additional bits in SCR_EL3 that can override the PSTATE setting for some but not all cases (makes perfect sense, I know...). When aborts are unmasked in PSTATE, but SCR.EA is not set, then synchronous external aborts will cause an exception while asynchronous external aborts will not. It turns out we never intialize SCR in coreboot and on RK3399 it comes up with all zeroes (even the reserved-1 bits, which is super weird). If you get an asynchronous external abort in coreboot it will silently hide in the CPU until BL31 enables SCR.EA before it has its own console handlers registered and silently hangs. This patch resolves the issue by also initializing SCR to a known good state early in the bootblock. It also cleans up some bit defintions and slightly reworks the DAIF unmasking... it doesn't actually make that much sense to unmask anything before our console and exception handlers are up. The new code will mask everything until the exception handler is installed and then unmask it, so that if there was a super early external abort we could still see it. (Of course there are still dozens of other processor exceptions that could happen which we have no way to mask.) Change-Id: I5266481a7aaf0b72aca8988accb671d92739af6f Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/37463 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Hung-Te Lin <hungte@chromium.org>
2019-12-04 07:47:01 +01:00
/* Initialize SCR with defaults for running without secure monitor
(disable all traps, enable all instructions, run NS at AArch64). */
raw_write_scr_el3(SCR_FIEN | SCR_API | SCR_APK | SCR_ST | SCR_RW |
SCR_HCE | SCR_SMD | SCR_RES1 | SCR_NS);
arm64: tegra132: tegra210: Remove old arm64/stage_entry.S This patch removes the old arm64/stage_entry.S code that was too specific to the Tegra SoC boot flow, and replaces it with code that hides the peculiarities of switching to a different CPU/arch in ramstage in the Tegra SoC directories. BRANCH=None BUG=None TEST=Built Ryu and Smaug. !!!UNTESTED!!! Change-Id: Ib3a0448b30ac9c7132581464573efd5e86e03698 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: http://review.coreboot.org/12078 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2015-10-16 22:10:02 +02:00
/* Initialize CPTR to not trap anything to EL3. */
raw_write_cptr_el3(CPTR_EL3_TCPAC_DISABLE | CPTR_EL3_TTA_DISABLE |
CPTR_EL3_TFP_DISABLE);
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
arm64: Make SPSR exception masking on EL2 transition explicit The configuration of SPSR bits that mask processor exceptions is kinda oddly hidden as an implict part of the transition() function right now. It would be odd but not impossible for programs to want to be entered with enabled exceptions, so let's move these bits to be explicitly set by the caller like the rest of SPSR instead. Also clear up some macro names. The SPSR[I] bit is currently defined as SPSR_IRQ_ENABLE, which is particularly unfortunate since that bit actually *disables* (masks) interrupts. The fact that there is an additional SPSR_IRQ_MASK definition with the same value but a different purpose doesn't really help. There's rarely a point to have all three of xxx_SHIFT, xxx_MASK and xxx_VALUE macros for single-bit fields, so simplify this to a single definition per bit. (Other macros in lib_helpers.h should probably also be overhauled to conform, but I want to wait and see how many of them really stay relevant after upcoming changes first.) BRANCH=None BUG=None TEST=None Change-Id: Id126f70d365467e43b7f493c341542247e5026d2 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 715600c83aef9794d1674e8c3b62469bdc57f297 Original-Change-Id: I3edc4ee276feb8610a636ec7b4175706505d58bd Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/270785 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/10250 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-05-13 20:19:33 +02:00
/* ELR/SPSR: Write entry point and processor state of program */
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
raw_write_elr_el3(elx->elr);
raw_write_spsr_el3(elx->spsr);
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
arm64: Correctly unmask asynchronous SError interrupts Arm CPUs have always had an odd feature that allows you to mask not only true interrupts, but also "external aborts" (memory bus errors from outside the CPU). CPUs usually have all of these masked after reset, which we quickly learned was a bad idea back when bringing up the first arm32 systems in coreboot. Masking external aborts means that if any of your firmware code does an illegal memory access, you will only see it once the kernel comes up and unmasks the abort (not when it happens). Therefore, we always unmask everything in early bootblock assembly code. When arm64 came around, it had very similar masking bits and we did the same there, thinking the issue resolved. Unfortunately Arm, in their ceaseless struggle for more complexity, decided that having a single bit to control this masking behavior is no longer enough: on AArch64, in addition to the PSTATE.DAIF bits that are analogous to arm32's CPSR, there are additional bits in SCR_EL3 that can override the PSTATE setting for some but not all cases (makes perfect sense, I know...). When aborts are unmasked in PSTATE, but SCR.EA is not set, then synchronous external aborts will cause an exception while asynchronous external aborts will not. It turns out we never intialize SCR in coreboot and on RK3399 it comes up with all zeroes (even the reserved-1 bits, which is super weird). If you get an asynchronous external abort in coreboot it will silently hide in the CPU until BL31 enables SCR.EA before it has its own console handlers registered and silently hangs. This patch resolves the issue by also initializing SCR to a known good state early in the bootblock. It also cleans up some bit defintions and slightly reworks the DAIF unmasking... it doesn't actually make that much sense to unmask anything before our console and exception handlers are up. The new code will mask everything until the exception handler is installed and then unmask it, so that if there was a super early external abort we could still see it. (Of course there are still dozens of other processor exceptions that could happen which we have no way to mask.) Change-Id: I5266481a7aaf0b72aca8988accb671d92739af6f Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/c/coreboot/+/37463 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Hung-Te Lin <hungte@chromium.org>
2019-12-04 07:47:01 +01:00
/* SCTLR: Initialize EL with everything disabled */
raw_write_sctlr_el2(SCTLR_RES1);
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
/* SP_ELx: Initialize stack pointer */
arm64: Drop checks for current exception level, hardcode EL3 assumption When we first created the arm64 port, we weren't quite sure whether coreboot would always run in EL3 on all platforms. The AArch64 A.R.M. technically considers this exception level optional, but in practice all SoCs seem to support it. We have since accumulated a lot of code that already hardcodes an implicit or explicit assumption of executing in EL3 somewhere, so coreboot wouldn't work on a system that tries to enter it in EL1/2 right now anyway. However, some of our low level support libraries (in particular those for accessing architectural registers) still have provisions for running at different exception levels built-in, and often use switch statements over the current exception level to decide which register to access. This includes an unnecessarily large amount of code for what should be single-instruction operations and precludes further optimization via inlining. This patch removes any remaining code that dynamically depends on the current exception level and makes the assumption that coreboot executes at EL3 official. If this ever needs to change for a future platform, it would probably be cleaner to set the expected exception level in a Kconfig rather than always probing it at runtime. Change-Id: I1a9fb9b4227bd15a013080d1c7eabd48515fdb67 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27880 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:14:45 +02:00
raw_write_sp_el2(elx->sp_elx);
arm64: Disable MMU during legacy payload handoff (without Arm TF) coreboot payloads expect to be entered with MMU disabled on arm64. The usual path via Arm TF already does this, so let's align the legacy path (without Secure Monitor) to do the same. Change-Id: I18717e00c905123d53b27a81185b534ba819c7b3 Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/27878 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-04 02:07:51 +02:00
/* Payloads expect to be entered with MMU disabled. Includes an ISB. */
mmu_disable();
arm64: Add support for transition library Transition library provides the following functionalities: 1) Setup the environment for switching to any particular EL and jump to the loaded program at that EL. In short "Execute program X at exception level Y using the state Z" 2) Provides routines for exception entry and exception exit that can be used by any program to implement exception handling. The only routine required by the program would be exc_dispatch which handles the exception in its own required way and returns by making a call to exc_exit. On exc_exit, the transition library unwinds the whole stack by popping out the saved state of xregs BUG=chrome-os-partner:30785 BRANCH=None TEST=Compiles successfully and exceptions are tested for ramstage on ryu Change-Id: I8116556109665e61a53e4b3987d649e3cfed64a1 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 8ab888e8cae0c5f1e79b0e16ca292869f16f1cca Original-Change-Id: I90f664ac657258724dc0c79bd9f6ceef70064f90 Original-Signed-off-by: Furquan Shaikh <furquan@google.com> Original-Reviewed-on: https://chromium-review.googlesource.com/216375 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/9070 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-08-31 06:59:11 +02:00
/* Eret to the entry point */
trans_switch(regs);
}
Reference in a new issue Copy permalink