target/riscv-013: clear sticky error when DMI operation fails

When a DMI operation does not succeed (either because of a timeout
or an error), the specification says that the error in the `op`
field is sticky and needs to cleared by writing `dmireset` in `dtmcs`.
This is already done for timeouts in increase_dmi_busy_delay
but not for errors.

Change-Id: I7c5f27a5cf145511a1a8b64a45a586521e1cbe41
Signed-off-by: Amaury Pouly <amaury.pouly@lowrisc.org>
Reviewed-on: https://review.openocd.org/c/openocd/+/7688
Tested-by: jenkins
Reviewed-by: Tim Newsome <tim@sifive.com>
Reviewed-by: Jan Matyas <jan.matyas@codasip.com>

diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c
index 4e6c8dc36d3be7fd7a1f463ebb3a1b3efa6aed76..2f4a8fe2e6f1dd67a473587fd6740534789eaaca 100644 (file)
--- a/src/target/riscv/riscv-013.c
+++ b/src/target/riscv/riscv-013.c
@@ -598,6 +598,7 @@ static int dmi_op_timeout(struct target *target, uint32_t *data_in,
                        break;
                } else {
                        LOG_ERROR("failed %s at 0x%x, status=%d", op_name, address, status);
+                       dtmcontrol_scan(target, DTM_DTMCS_DMIRESET);
                        return ERROR_FAIL;
                }
                if (time(NULL) - start > timeout_sec)
@@ -630,6 +631,7 @@ static int dmi_op_timeout(struct target *target, uint32_t *data_in,
                                        LOG_ERROR("Failed %s (NOP) at 0x%x; status=%d", op_name, address,
                                                        status);
                                }
+                               dtmcontrol_scan(target, DTM_DTMCS_DMIRESET);
                                return ERROR_FAIL;
                        }
                        if (time(NULL) - start > timeout_sec)