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2019-12-05arm64: Correctly unmask asynchronous SError interruptsJulius Werner
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>
2019-08-26AUTHORS: Move src/arch/arm64 copyrights into AUTHORS fileMartin Roth
As discussed on the mailing list and voted upon, the coreboot project is going to move the majority of copyrights out of the headers and into an AUTHORS file. This will happen a bit at a time, as we'll be unifying license headers at the same time. Additional changes in this patch: - Make sure files say that they're part of the coreboot project - Move descriptions below the license header Note that the file include/arch/acpi.h is a fantastic example of why moving to the authors file is needed. Excluding the guard statements, it has 8 lines of copyrights for 3 function declarations. Signed-off-by: Martin Roth <martin@coreboot.org> Change-Id: I334baab2b4311eb1bd9ce3f67f49a68e8b73630c Reviewed-on: https://review.coreboot.org/c/coreboot/+/34606 Reviewed-by: Patrick Georgi <pgeorgi@google.com> Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2018-11-16src: Remove unneeded include <console/console.h>Elyes HAOUAS
Change-Id: I40f8b4c7cbc55e16929b1f40d18bb5a9c19845da Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr> Reviewed-on: https://review.coreboot.org/29289 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2018-10-08Move compiler.h to commonlibNico Huber
Its spreading copies got out of sync. And as it is not a standard header but used in commonlib code, it belongs into commonlib. While we are at it, always include it via GCC's `-include` switch. Some Windows and BSD quirk handling went into the util copies. We always guard from redefinitions now to prevent further issues. Change-Id: I850414e6db1d799dce71ff2dc044e6a000ad2552 Signed-off-by: Nico Huber <nico.h@gmx.de> Reviewed-on: https://review.coreboot.org/28927 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2018-08-10arm64: Drop checks for current exception level, hardcode EL3 assumptionJulius Werner
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>
2018-08-07arm64: Disable MMU during legacy payload handoff (without Arm TF)Julius Werner
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>
2018-04-24compiler.h: add __weak macroAaron Durbin
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>
2015-11-17arm64: tegra132: tegra210: Remove old arm64/stage_entry.SJulius Werner
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>
2015-10-31tree: drop last paragraph of GPL copyright headerPatrick Georgi
It encourages users from writing to the FSF without giving an address. Linux also prefers to drop that and their checkpatch.pl (that we imported) looks out for that. This is the result of util/scripts/no-fsf-addresses.sh with no further editing. Change-Id: Ie96faea295fe001911d77dbc51e9a6789558fbd6 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Reviewed-on: http://review.coreboot.org/11888 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2015-05-21Remove address from GPLv2 headersPatrick Georgi
As per discussion with lawyers[tm], it's not a good idea to shorten the license header too much - not for legal reasons but because there are tools that look for them, and giving them a standard pattern simplifies things. However, we got confirmation that we don't have to update every file ever added to coreboot whenever the FSF gets a new lease, but can drop the address instead. util/kconfig is excluded because that's imported code that we may want to synchronize every now and then. $ find * -type f -exec sed -i "s:Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, *MA[, ]*02110-1301[, ]*USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 59 Temple Place[-, ]*Suite 330, Boston, MA *02111-1307[, ]*USA:Foundation, Inc.:" {} + $ find * -type f -exec sed -i "s:Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.:Foundation, Inc.:" {} + $ find * -type f -a \! -name \*.patch \ -a \! -name \*_shipped \ -a \! -name LICENSE_GPL \ -a \! -name LGPL.txt \ -a \! -name COPYING \ -a \! -name DISCLAIMER \ -exec sed -i "/Foundation, Inc./ N;s:Foundation, Inc.* USA\.* *:Foundation, Inc. :;s:Foundation, Inc. $:Foundation, Inc.:" {} + Change-Id: Icc968a5a5f3a5df8d32b940f9cdb35350654bef9 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Reviewed-on: http://review.coreboot.org/9233 Tested-by: build bot (Jenkins) Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
2015-05-19arm64: Make SPSR exception masking on EL2 transition explicitJulius Werner
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>
2015-03-28arm64: Add support for transition libraryFurquan Shaikh
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>