[PATCH]: ca38e918f1 Add MPU detection logic to FreeRTOS thread's stack parsing.

[gerrit]

This is an automated email from Gerrit.

"Mateus Campaner Hercules <mchercu...@gmail.com>" just uploaded a new patch set 
to Gerrit, which you can find at https://review.openocd.org/c/openocd/+/7478

-- gerrit

commit ca38e918f157ca44d4f2d5ca33a56c13f94e2a4e
Author: Mateus Campaner Hercules <mchercu...@gmail.com>
Date:   Wed Feb 15 13:19:08 2023 -0300

    Add MPU detection logic to FreeRTOS thread's stack parsing.
    
    Created a variable holding true if a default mpu is available
    on target and it's enabled. Both FreeRTOS cortex-m4 & cortex-m3
    ports with MPU target the default peripheral from ARM.
    
    If target is based on armv7m, it will have a MPU_TYPE register,
    as it's noted as always implemented by ARM documentation. This
    register's DREGION byte indicates if a proper MPU is available
    on target. As said before only the default MPU is supported by
    this code snippet.
    
    Signed-off-by: Mateus Campaner Hercules <mchercu...@gmail.com>
    Change-Id: I47da134bd6a8fef4fe0127c45836a08bb28315d8

diff --git a/src/rtos/FreeRTOS.c b/src/rtos/FreeRTOS.c
index 0dbe019792..dbd9cb97db 100644
--- a/src/rtos/FreeRTOS.c
+++ b/src/rtos/FreeRTOS.c
@@ -448,6 +448,36 @@ static int freertos_get_thread_reg_list(struct rtos *rtos, 
int64_t thread_id,
                }
        }
 
+       /* Check for armv7m with *implemented* MPU, i.e. some vendors use a 
custom implementation */
+       int cm4_mpu_enabled = 0;
+       if (is_armv7m(armv7m_target)) {
+               /* MPU_TYPE is always implemented on armv7m */
+               uint32_t mpu_type;
+
+               retval = target_read_u32(rtos->target, MPU_TYPE, &mpu_type);
+               if (retval != ERROR_OK) {
+                       LOG_ERROR("Could not read MPU_TYPE register to check if 
MPU is implemented");
+                       return -1;
+               }
+
+               /* Check if DREGION is not zero */
+               if (mpu_type & 0x0000FF00) {
+                       uint32_t mpu_ctrl;
+
+                       retval = target_read_u32(rtos->target, MPU_CTRL, 
&mpu_ctrl);
+                       if (retval != ERROR_OK) {
+                               LOG_ERROR("Could not read MPU_CTRL on a mpu 
present core");
+                               return -1;
+                       }
+
+                       /* Check if ENABLE bit of MPU_CTRL is enabled */
+                       if (mpu_ctrl & 0x00000001) {
+                               /* Found target with enabled MPU */
+                               cm4_mpu_enabled = 1;
+                       }
+               }
+       }
+
        if (cm4_fpu_enabled == 1) {
                /* Read the LR to decide between stacking with or without FPU */
                uint32_t lr_svc = 0;

--