stm32: Add floating point register read/write.

This patch add floating point register read/write
functionality through the SCS debug interface.

Change-Id: Id20e109dd7cccba00671d55ca8aabeb4936cceb9
Signed-off-by: Mathias K <kesmtp@freenet.de>
Reviewed-on: http://openocd.zylin.com/512
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/src/target/stm32_stlink.c b/src/target/stm32_stlink.c
index 64e83f534e6346d03b55befbef071fecc72e03d0..d2f38e5af384d4eb8194977ac01022472baf30ae 100644 (file)
--- a/src/target/stm32_stlink.c
+++ b/src/target/stm32_stlink.c
@@ -38,6 +38,9 @@
 #include "cortex_m.h"
 #include "arm_semihosting.h"
 
+#define ARMV7M_SCS_DCRSR       0xe000edf4
+#define ARMV7M_SCS_DCRDR       0xe000edf8
+
 static inline struct stlink_interface_s *target_to_stlink(struct target *target)
 {
        return target->tap->priv;
@@ -65,8 +68,19 @@ static int stm32_stlink_load_core_reg_u32(struct target *target,
                        LOG_ERROR("JTAG failure %i", retval);
                        return ERROR_JTAG_DEVICE_ERROR;
                }
-               LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "",
-                         (int)num, *value);
+               LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "", (int)num, *value);
+               break;
+
+       case 33:
+       case 64 ... 96:
+               /* Floating-point Status and Registers */
+               retval = target_write_u32(target, ARMV7M_SCS_DCRSR, num);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_read_u32(target, ARMV7M_SCS_DCRDR, value);
+               if (retval != ERROR_OK)
+                       return retval;
+               LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "", (int)num, *value);
                break;
 
        case ARMV7M_PRIMASK:
@@ -150,6 +164,18 @@ static int stm32_stlink_store_core_reg_u32(struct target *target,
                LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value);
                break;
 
+       case 33:
+       case 64 ... 96:
+               /* Floating-point Status and Registers */
+               retval = target_write_u32(target, ARMV7M_SCS_DCRDR, value);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u32(target, ARMV7M_SCS_DCRSR, num | (1<<16));
+               if (retval != ERROR_OK)
+                       return retval;
+               LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value);
+               break;
+
        case ARMV7M_PRIMASK:
        case ARMV7M_BASEPRI:
        case ARMV7M_FAULTMASK: