The branch_if_master macro jumps to a label if the CPU is the "master" core, which we define as having all affinity levels set to 0. To check for this condition, we need to mask off some bits from the MPIDR register, then compare the remaining register value against zero. The implementation of this was slighly broken (it preserved the upper RES0 bits), overly complicated and hard to understand, especially since it lacked comments. The same was true for the very similar branch_if_slave macro. Use a much shorter assembly sequence for those checks, use the same masking for both macros (just negate the final branch), and put some comments on them, to make it clear what the code does. This allows to drop the second temporary register for branch_if_master, so we adjust all call sites as well. Also use the opportunity to remove a misleading comment: the macro works fine on SoCs with multiple clusters. Judging by the commit message, the original problem with the Juno SoC stems from the fact that the master CPU *can* be configured to be from cluster 1, so the assumption that the master CPU has all affinity values set to 0 does not hold there. But this is already mentioned above in a comment, so remove the extra comment. Signed-off-by: Andre Przywara <andre.przywara@arm.com>
The switch_el macro is a neat contraption to handle cases where we need different code depending on the current exception level, but its implementation was longer than needed. Simplify it by doing just one comparison, then using the different condition codes to branch to the desired target. PState.CurrentEL just holds two bits, and since we don't care about EL0, we can use >, =, < to select EL3, EL2 and EL1, respectively. Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>
Per a request from Andre Przywara and agreed with by Peter Hoyes, the vexpress aemv8r support wasn't quite ready to be merged, but the discussion had moved off list. We should keep the first patch in the series for now, but revert the rest. This reverts the following commits: e0bd6f31ce41 doc: Add documentation for the Arm vexpress board configs 30e5a449e8c7 arm: Use armv8_switch_to_el1 env to switch to EL1 b53bbca63bf4 vexpress64: Add BASER_FVP vexpress board variant 2f5b7b74903f armv8: Add ARMv8 MPU configuration logic 37a757e227cc armv8: Ensure EL1&0 VMSA is enabled Signed-off-by: Tom Rini <trini@konsulko.com>
On Armv8-R, the EL1&0 memory system architecture is configurable as a VMSA or PMSA, and resets to an "architecturally unknown" value. Add code to armv8_switch_to_el1_m which detects whether the MSA at EL1&0 is configurable using the id_aa64mmfr0_el1 register MSA fields. If it is we must ensure the VMSA is enabled so that a rich OS can boot. The MSA and MSA_FRAC fields are described in the Armv8-R architecture profile supplement (section G1.3.7): https://developer.arm.com/documentation/ddi0600/latest/ Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com>
The use of ARMv8.3 pointer authentication (PAuth) is governed by fields in HCR_EL2, which trigger a 'trap to EL2' if not enabled. The reset value of these fields is 'architecturally unknown' so we must ensure that the fields are enabled (to disable the traps) if we are entering the kernel at EL1. The APK field disables PAuth instruction traps and the API field disables PAuth register traps Add code to disable the traps in armv8_switch_to_el1_m. Prior to doing so, it checks fields in the ID_AA64ISAR1_EL1 register to ensure pointer authentication is supported by the hardware. The runtime checks require a second temporary register, so add this to the EL1 transition macro signature and update 2 call sites. Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com>
CNTFRQ_EL0 is only writable from the highest supported exception level on the platform. For Armv8-A, this is typically EL3, but technically EL2 and EL3 are optional so it may need to be initialized at EL2 or EL1. For Armv8-R, the highest exception level is always EL2. This patch moves the initialization outside of the switch_el block and uses a new macro branch_if_not_highest_el which dynamically detects whether it is at the highest supported exception level. Linux's docs state that CNTFRQ_EL0 should be initialized by the bootloader. If not set, the the U-Boot prompt countdown hangs. Signed-off-by: Peter Hoyes <Peter.Hoyes@arm.com>
Allow EL3 to handle all the External Abort and SError interrupt exception occur in all exception levels. Signed-off-by: Chee Hong Ang <chee.hong.ang@intel.com>
When U-Boot started using SPDX tags we were among the early adopters and there weren't a lot of other examples to borrow from. So we picked the area of the file that usually had a full license text and replaced it with an appropriate SPDX-License-Identifier: entry. Since then, the Linux Kernel has adopted SPDX tags and they place it as the very first line in a file (except where shebangs are used, then it's second line) and with slightly different comment styles than us. In part due to community overlap, in part due to better tag visibility and in part for other minor reasons, switch over to that style. This commit changes all instances where we have a single declared license in the tag as both the before and after are identical in tag contents. There's also a few places where I found we did not have a tag and have introduced one. Signed-off-by: Tom Rini <trini@konsulko.com>
macro branch_if_master checks master CPU via (Aff3 & (Aff2:Aff1:Aff0)) it is simple but a little obscure. fix by checking Affx fields within MPIDR_EL1 directly. Signed-off-by: zijun_hu <zijun_hu@htc.com>