target/arm_adi_v5,arm_dap: introduce pre_connect_init() dap operation

SWD multidrop requires some initialization once before connecting
all daps. Provide an optional pre-connect dap operation.

Change-Id: I778215c512c56423a425dda80ab19a739f22f285
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: https://review.openocd.org/c/openocd/+/7542
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

diff --git a/src/target/arm_adi_v5.h b/src/target/arm_adi_v5.h
index e07b577af683f047365b875bba7543fce4a418c8..fc7fdafd84cf72f84cec4f07772ebff850c434dd 100644 (file)
--- a/src/target/arm_adi_v5.h
+++ b/src/target/arm_adi_v5.h
@@ -420,6 +420,9 @@ struct adiv5_dap {
  * available until run().
  */
 struct dap_ops {
+       /** Optional; called once on the first enabled dap before connecting */
+       int (*pre_connect_init)(struct adiv5_dap *dap);
+
        /** connect operation for SWD */
        int (*connect)(struct adiv5_dap *dap);
 

diff --git a/src/target/arm_dap.c b/src/target/arm_dap.c
index 84cc6c743bd14f797b2b70192977a70a5d77f8bb..9f4afae74372b2c287fa935094224a830cfc88eb 100644 (file)
--- a/src/target/arm_dap.c
+++ b/src/target/arm_dap.c
@@ -91,6 +91,7 @@ static int dap_init_all(void)
 {
        struct arm_dap_object *obj;
        int retval;
+       bool pre_connect = true;
 
        LOG_DEBUG("Initializing all DAPs ...");
 
@@ -123,6 +124,14 @@ static int dap_init_all(void)
                                is_adiv6(dap) ? "ADIv6" : "ADIv5");
                }
 
+               if (pre_connect && dap->ops->pre_connect_init) {
+                       retval = dap->ops->pre_connect_init(dap);
+                       if (retval != ERROR_OK)
+                               return retval;
+
+                       pre_connect = false;
+               }
+
                retval = dap->ops->connect(dap);
                if (retval != ERROR_OK)
                        return retval;