adiv5: check packed transfers are supported

Currently we try and use MEM-AP packed transfers as much as possible for
8/16bit transfers. However not all targets support packed transfers, so
check before using.

Change-Id: I66256007f25ccd0c583f23db5acf6d1aa8b5e57d
Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Reviewed-on: http://openocd.zylin.com/1602
Tested-by: jenkins
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>

diff --git a/src/target/arm_adi_v5.c b/src/target/arm_adi_v5.c
index ce92f4cc98d4ce74f73d0bad4e6b0fbae5df62bc..5e9091f729fcf537a3cecc7619d8936935ebeea4 100644 (file)
--- a/src/target/arm_adi_v5.c
+++ b/src/target/arm_adi_v5.c
@@ -416,7 +416,7 @@ int mem_ap_write_buf_u16(struct adiv5_dap *dap, const uint8_t *buffer, int count
 {
        int retval = ERROR_OK;
 
-       if (count >= 4)
+       if (dap->packed_transfers && count >= 4)
                return mem_ap_write_buf_packed_u16(dap, buffer, count, address);
 
        while (count > 0) {
@@ -516,7 +516,7 @@ int mem_ap_write_buf_u8(struct adiv5_dap *dap, const uint8_t *buffer, int count,
 {
        int retval = ERROR_OK;
 
-       if (count >= 4)
+       if (dap->packed_transfers && count >= 4)
                return mem_ap_write_buf_packed_u8(dap, buffer, count, address);
 
        while (count > 0) {
@@ -685,7 +685,7 @@ int mem_ap_read_buf_u16(struct adiv5_dap *dap, uint8_t *buffer,
        uint32_t invalue, i;
        int retval = ERROR_OK;
 
-       if (count >= 4)
+       if (dap->packed_transfers && count >= 4)
                return mem_ap_read_buf_packed_u16(dap, buffer, count, address);
 
        while (count > 0) {
@@ -787,7 +787,7 @@ int mem_ap_read_buf_u8(struct adiv5_dap *dap, uint8_t *buffer,
        uint32_t invalue;
        int retval = ERROR_OK;
 
-       if (count >= 4)
+       if (dap->packed_transfers && count >= 4)
                return mem_ap_read_buf_packed_u8(dap, buffer, count, address);
 
        while (count > 0) {
@@ -1164,6 +1164,29 @@ int ahbap_debugport_init(struct adiv5_dap *dap)
 
        dap_syssec(dap);
 
+       /* check that we support packed transfers */
+       uint32_t csw;
+
+       retval = dap_setup_accessport(dap, CSW_8BIT | CSW_ADDRINC_PACKED, 0);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = dap_queue_ap_read(dap, AP_REG_CSW, &csw);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = dap_run(dap);
+       if (retval != ERROR_OK)
+               return retval;
+
+       if (csw & CSW_ADDRINC_PACKED)
+               dap->packed_transfers = true;
+       else
+               dap->packed_transfers = false;
+
+       LOG_DEBUG("MEM_AP Packed Transfers: %s",
+                       dap->packed_transfers ? "enabled" : "disabled");
+
        return ERROR_OK;
 }
 

diff --git a/src/target/arm_adi_v5.h b/src/target/arm_adi_v5.h
index e2e83e11e9ebfaca27125784843b501f1b42f7fa..7cc90b241521ee77e5939244404eb4d9f289d049 100644 (file)
--- a/src/target/arm_adi_v5.h
+++ b/src/target/arm_adi_v5.h
@@ -186,6 +186,9 @@ struct adiv5_dap {
 
        /* Size of TAR autoincrement block, ARM ADI Specification requires at least 10 bits */
        uint32_t tar_autoincr_block;
+
+       /* true if packed transfers are supported by the MEM-AP */
+       bool packed_transfers;
 };
 
 /**