cortex_m: Do additional initialization during reset

[openocd.git] / src / target / adi_v5_cmsis_dap.c

diff --git a/src/target/adi_v5_cmsis_dap.c b/src/target/adi_v5_cmsis_dap.c
index 95d1cea3087a904397f7e8354166e1dc433c581a..9b591464394c18925d4f68887e48a2df81511c82 100644 (file)
--- a/src/target/adi_v5_cmsis_dap.c
+++ b/src/target/adi_v5_cmsis_dap.c
@@ -54,14 +54,26 @@
 /* YUK! - but this is currently a global.... */
 extern struct jtag_interface *jtag_interface;
 
-static int (cmsis_dap_queue_ap_abort)(struct adiv5_dap *dap, uint8_t *ack)
+static int cmsis_dap_clear_sticky_errors(struct adiv5_dap *dap)
 {
-       LOG_DEBUG("CMSIS-ADI: cmsis_dap_queue_ap_abort");
+       LOG_DEBUG("CMSIS-ADI: %s", __func__);
 
-       /* FIXME: implement this properly cmsis-dap has DAP_WriteABORT()
-        * for now just hack @ everything */
-       return jtag_interface->swd->write_reg(
-                       (CMSIS_CMD_DP | CMSIS_CMD_WRITE | CMSIS_CMD_A32(DP_ABORT)), 0x1e);
+       const struct swd_driver *swd = jtag_interface->swd;
+       assert(swd);
+
+       return swd->write_reg(swd_cmd(false,  false, DP_ABORT),
+                             STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR);
+}
+
+static int cmsis_dap_queue_ap_abort(struct adiv5_dap *dap, uint8_t *ack)
+{
+       LOG_DEBUG("CMSIS-ADI: %s", __func__);
+
+       const struct swd_driver *swd = jtag_interface->swd;
+       assert(swd);
+
+       return swd->write_reg(swd_cmd(false,  false, DP_ABORT),
+                             DAPABORT | STKCMPCLR | STKERRCLR | WDERRCLR | ORUNERRCLR);
 }
 
 static int cmsis_dap_queue_dp_read(struct adiv5_dap *dap, unsigned reg, uint32_t *data)
@@ -71,11 +83,8 @@ static int cmsis_dap_queue_dp_read(struct adiv5_dap *dap, unsigned reg, uint32_t
        int retval = jtag_interface->swd->read_reg(
                        (CMSIS_CMD_DP | CMSIS_CMD_READ | CMSIS_CMD_A32(reg)), data);
 
-       if (retval != ERROR_OK) {
-               /* fault response */
-               uint8_t ack = retval & 0xff;
-               cmsis_dap_queue_ap_abort(dap, &ack);
-       }
+       if (retval != ERROR_OK)
+               cmsis_dap_clear_sticky_errors(dap);
 
        return retval;
 }
@@ -94,11 +103,8 @@ static int (cmsis_dap_queue_dp_write)(struct adiv5_dap *dap, unsigned reg, uint3
        int retval = jtag_interface->swd->write_reg(
                        (CMSIS_CMD_DP | CMSIS_CMD_WRITE | CMSIS_CMD_A32(reg)), data);
 
-       if (retval != ERROR_OK) {
-               /* fault response */
-               uint8_t ack = retval & 0xff;
-               cmsis_dap_queue_ap_abort(dap, &ack);
-       }
+       if (retval != ERROR_OK)
+               cmsis_dap_clear_sticky_errors(dap);
 
        return retval;
 }
@@ -128,11 +134,8 @@ static int (cmsis_dap_queue_ap_read)(struct adiv5_dap *dap, unsigned reg, uint32
        retval = jtag_interface->swd->read_reg(
                        (CMSIS_CMD_AP | CMSIS_CMD_READ | CMSIS_CMD_A32(reg)), data);
 
-       if (retval != ERROR_OK) {
-               /* fault response */
-               uint8_t ack = retval & 0xff;
-               cmsis_dap_queue_ap_abort(dap, &ack);
-       }
+       if (retval != ERROR_OK)
+               cmsis_dap_clear_sticky_errors(dap);
 
        return retval;
 }
@@ -155,11 +158,8 @@ static int (cmsis_dap_queue_ap_write)(struct adiv5_dap *dap, unsigned reg, uint3
        retval = jtag_interface->swd->write_reg(
                        (CMSIS_CMD_AP | CMSIS_CMD_WRITE | CMSIS_CMD_A32(reg)), data);
 
-       if (retval != ERROR_OK) {
-               /* fault response */
-               uint8_t ack = retval & 0xff;
-               cmsis_dap_queue_ap_abort(dap, &ack);
-       }
+       if (retval != ERROR_OK)
+               cmsis_dap_clear_sticky_errors(dap);
 
        return retval;
 }
@@ -167,10 +167,38 @@ static int (cmsis_dap_queue_ap_write)(struct adiv5_dap *dap, unsigned reg, uint3
 /** Executes all queued DAP operations. */
 static int cmsis_dap_run(struct adiv5_dap *dap)
 {
-       LOG_DEBUG("CMSIS-ADI: cmsis_dap_run");
+       LOG_DEBUG(" ");
        /* FIXME: for now the CMSIS-DAP interface hard-wires a zero-size queue. */
+       int ret;
+       uint32_t ctrlstat;
 
-       return ERROR_OK;
+       /*
+         Some debug dongles do more than asked for(e.g. EDBG from
+         Atmel) behind the scene and issuing an AP write
+         may result in more than just APACC SWD transaction, which in
+         turn can possibly set sticky error bit in CTRL/STAT register
+         of the DP(an example would be writing SYSRESETREQ to AIRCR).
+         Such adapters may interpret CMSIS-DAP secification
+         differently and not guarantee to be report those failures
+         via status byte of the return USB packet from CMSIS-DAP, so
+         we need to check CTRL/STAT and if that happens to clear it.
+       */
+       ret = cmsis_dap_queue_dp_read(dap, DP_CTRL_STAT, &ctrlstat);
+       if (ret != ERROR_OK) {
+               LOG_ERROR("Failed to read CTRL/STAT register");
+               return ret;
+       }
+
+       if (ctrlstat & SSTICKYERR) {
+               LOG_WARNING("SSTICKYERR was set, clearing it");
+               ret = cmsis_dap_clear_sticky_errors(dap);
+               if (ret != ERROR_OK) {
+                       LOG_ERROR("Failed to clear sticky errors");
+                       return ret;
+               }
+       }
+
+       return ret;
 }
 
 const struct dap_ops cmsis_dap_ops = {
@@ -276,15 +304,13 @@ static int cmsis_dap_init(struct command_context *ctx)
        }
 #endif
 
-       uint8_t ack = 0;
-
        status = cmsis_dap_queue_dp_read(dap, DP_IDCODE, &idcode);
 
        if (status == ERROR_OK)
                LOG_INFO("IDCODE 0x%08" PRIx32, idcode);
 
        /* force clear all sticky faults */
-       cmsis_dap_queue_ap_abort(dap, &ack);
+       cmsis_dap_clear_sticky_errors(dap);
 
        /* this is a workaround to get polling working */
        jtag_add_reset(0, 0);