[PATCH]: 6ec8c9709 target:armv8: aarch32 do not try to restore same EL

[gerrit]

This is an automated email from Gerrit.

"Julien Massot <julien.mas...@iot.bzh>" just uploaded a new patch set to 
Gerrit, which you can find at https://review.openocd.org/c/openocd/+/6807

-- gerrit

commit 6ec8c9709448a8d5e7fc868124fae6fc07273b41
Author: Julien Massot <julien.mas...@iot.bzh>
Date:   Wed Jan 12 14:10:36 2022 +0100

    target:armv8: aarch32 do not try to restore same EL
    
    While debugging a Cortex-R52 OpenOCD fail to restore context
    on line
    retval = dpm->instr_write_data_r0(dpm,
                    ARMV8_MSR_GP_xPSR_T1(1, 0, 15), cpsr);
    
    which trigger this exception:
    
    aarch64.c:1206 aarch64_restore_context(): r8a779a0.r52
    armv8_dpm.c:560 armv8_dpm_modeswitch(): restoring mode, cpsr = 0x0000011f
    1262753 armv8_dpm.c:598 armv8_dpm_modeswitch(): target_el = 1, last_el = 1
    armv8_dpm.c:611 armv8_dpm_modeswitch(): SPSR = 0x0000011f
    armv8_dpm.c:260 dpmv8_exec_opcode(): Opcode 0x8f00f390, DSCR.ERR=1, 
DSCR.EL=1
    
    and finally OpenOCD doesn't succeed to restore the processor.
    
    This check 'dpm->last_el != target_el' exist for aarch64,
    so might be correct for aarch32 too.
    
    Signed-off-by: Julien Massot <julien.mas...@iot.bzh>
    Change-Id: I41d1006233251dcaf6d69bda580488b204b7eb63

diff --git a/src/target/armv8_dpm.c b/src/target/armv8_dpm.c
index 188e58822..a684be7b9 100644
--- a/src/target/armv8_dpm.c
+++ b/src/target/armv8_dpm.c
@@ -606,7 +606,7 @@ int armv8_dpm_modeswitch(struct arm_dpm *dpm, enum arm_mode 
mode)
                core_state = armv8_dpm_get_core_state(dpm);
                if (core_state != ARM_STATE_AARCH64) {
                        /* cannot do DRPS/ERET when already in EL0 */
-                       if (dpm->last_el != 0) {
+                       if (dpm->last_el != 0 && dpm->last_el != target_el) {
                                /* load SPSR with the desired mode and execute 
DRPS */
                                LOG_DEBUG("SPSR = 0x%08"PRIx32, cpsr);
                                retval = dpm->instr_write_data_r0(dpm,

--