cortex_m: Discover the AP to use, just like Cortex-A

This required fixing the AP ID parsing in dap_find_ap() to
match IHI0031C. The AXI type was added too.

Change-Id: I44577a7848df37586e650dce0fb57ac26f5f858c
Signed-off-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>
Reviewed-on: http://openocd.zylin.com/3146
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

diff --git a/src/target/arm_adi_v5.c b/src/target/arm_adi_v5.c
index 53c0c4e15ae0af1dfb8de12645ac31b6506c4f1c..3a81784e301548e72ce1e6bcf53de335b1155f13 100644 (file)
--- a/src/target/arm_adi_v5.c
+++ b/src/target/arm_adi_v5.c
@@ -825,9 +825,10 @@ int dap_find_ap(struct adiv5_dap *dap, enum ap_type type_to_find, uint8_t *ap_nu
                 * 31-28 : Revision
                 * 27-24 : JEDEC bank (0x4 for ARM)
                 * 23-17 : JEDEC code (0x3B for ARM)
-                * 16    : Mem-AP
-                * 15-8  : Reserved
-                *  7-0  : AP Identity (1=AHB-AP 2=APB-AP 0x10=JTAG-AP)
+                * 16-13 : Class (0b1000=Mem-AP)
+                * 12-8  : Reserved
+                *  7-4  : AP Variant (non-zero for JTAG-AP)
+                *  3-0  : AP Type (0=JTAG-AP 1=AHB-AP 2=APB-AP 4=AXI-AP)
                 */
 
                /* Reading register for a non-existant AP should not cause an error,
@@ -835,11 +836,12 @@ int dap_find_ap(struct adiv5_dap *dap, enum ap_type type_to_find, uint8_t *ap_nu
                 */
                if ((retval == ERROR_OK) &&                  /* Register read success */
                        ((id_val & 0x0FFF0000) == 0x04770000) && /* Jedec codes match */
-                       ((id_val & 0xFF) == type_to_find)) {     /* type matches*/
+                       ((id_val & 0xF) == type_to_find)) {      /* type matches*/
 
                        LOG_DEBUG("Found %s at AP index: %d (IDR=0x%08" PRIX32 ")",
                                                (type_to_find == AP_TYPE_AHB_AP)  ? "AHB-AP"  :
                                                (type_to_find == AP_TYPE_APB_AP)  ? "APB-AP"  :
+                                               (type_to_find == AP_TYPE_AXI_AP)  ? "AXI-AP"  :
                                                (type_to_find == AP_TYPE_JTAG_AP) ? "JTAG-AP" : "Unknown",
                                                ap, id_val);
 
@@ -851,6 +853,7 @@ int dap_find_ap(struct adiv5_dap *dap, enum ap_type type_to_find, uint8_t *ap_nu
        LOG_DEBUG("No %s found",
                                (type_to_find == AP_TYPE_AHB_AP)  ? "AHB-AP"  :
                                (type_to_find == AP_TYPE_APB_AP)  ? "APB-AP"  :
+                               (type_to_find == AP_TYPE_AXI_AP)  ? "AXI-AP"  :
                                (type_to_find == AP_TYPE_JTAG_AP) ? "JTAG-AP" : "Unknown");
        return ERROR_FAIL;
 }

diff --git a/src/target/arm_adi_v5.h b/src/target/arm_adi_v5.h
index 32b723959ab140813802a014239a2bd4d94dd6af..85b622430c73643828142c6b3355ccef179dac8e 100644 (file)
--- a/src/target/arm_adi_v5.h
+++ b/src/target/arm_adi_v5.h
@@ -279,9 +279,10 @@ struct dap_ops {
  * Access Port types
  */
 enum ap_type {
-       AP_TYPE_AHB_AP  = 0x01,  /* AHB Memory-AP */
-       AP_TYPE_APB_AP  = 0x02,  /* APB Memory-AP */
-       AP_TYPE_JTAG_AP = 0x10   /* JTAG-AP - JTAG master for controlling other JTAG devices */
+       AP_TYPE_JTAG_AP = 0x0,  /* JTAG-AP - JTAG master for controlling other JTAG devices */
+       AP_TYPE_AHB_AP  = 0x1,  /* AHB Memory-AP */
+       AP_TYPE_APB_AP  = 0x2,  /* APB Memory-AP */
+       AP_TYPE_AXI_AP  = 0x4,  /* AXI Memory-AP */
 };
 
 /**

diff --git a/src/target/cortex_m.c b/src/target/cortex_m.c
index ec5caa288fe1a67c412970dc9091f8276033b8c9..7a7194a1174b25d3e17b1924bdcdc329527bee44 100644 (file)
--- a/src/target/cortex_m.c
+++ b/src/target/cortex_m.c
@@ -1903,6 +1903,13 @@ int cortex_m_examine(struct target *target)
        struct adiv5_dap *swjdp = cortex_m->armv7m.arm.dap;
        struct armv7m_common *armv7m = target_to_armv7m(target);
 
+       /* Search for the MEM-AP */
+       retval = dap_find_ap(swjdp, AP_TYPE_AHB_AP, &armv7m->debug_ap);
+       if (retval != ERROR_OK) {
+               LOG_ERROR("Could not find MEM-AP to control the core");
+               return retval;
+       }
+
        /* Leave (only) generic DAP stuff for debugport_init(); */
        swjdp->ap[armv7m->debug_ap].memaccess_tck = 8;