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| author | Kinsey Moore <kinsey.moore@oarcorp.com> | 2021-01-08 10:13:42 -0600 |
|---|---|---|
| committer | Joel Sherrill <joel@rtems.org> | 2021-03-05 08:43:15 -0600 |
| commit | a27ba3f20f8909cf6081bf8ab3114305e27c8a59 (patch) | |
| tree | c5db8b971ea0cb250333bfd4ad91bceff9526d02 /bsps/aarch64/shared | |
| parent | bsps/aarch64: RTEMS_DEBUG stack alignment faults (diff) | |
| download | rtems-a27ba3f20f8909cf6081bf8ab3114305e27c8a59.tar.bz2 | |
bsps/aarch64: Add support for EL2 start
Add the stub necessary to boot on AArch64 under EL2 and drop to EL1 for
normal operation.
Diffstat (limited to 'bsps/aarch64/shared')
| -rw-r--r-- | bsps/aarch64/shared/start/start.S | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/bsps/aarch64/shared/start/start.S b/bsps/aarch64/shared/start/start.S index e4dd3c2cee..3751545ee1 100644 --- a/bsps/aarch64/shared/start/start.S +++ b/bsps/aarch64/shared/start/start.S @@ -98,6 +98,31 @@ _start: #endif msr SCTLR_EL1, x0 +#ifdef BSP_START_IN_HYP_SUPPORT + /* Drop from EL2 to EL1 */ + + /* Configure HCR_EL2 */ + mrs x0, HCR_EL2 + /* Set EL1 Execution state to AArch64 */ + orr x0, x0, #(1<<31) + /* Disable ID traps */ + bic x0, x0, #(1<<15) + bic x0, x0, #(1<<16) + bic x0, x0, #(1<<17) + bic x0, x0, #(1<<18) + msr HCR_EL2, x0 + + /* Set to EL1h mode for eret */ + mov x0, #0b00101 + msr SPSR_EL2, x0 + + /* Set EL1 entry point */ + adr x0, _el1_start + msr ELR_EL2, x0 + eret +_el1_start: +#endif + #ifdef RTEMS_SMP /* Read MPIDR and get current processor index */ mrs x7, mpidr_el1 |