-#define DP_ZERO 0
-#define DP_CTRL_STAT 0x4
-#define DP_SELECT 0x8
-#define DP_RDBUFF 0xC
-
-#define CORUNDETECT (1 << 0)
-#define SSTICKYORUN (1 << 1)
-#define SSTICKYERR (1 << 5)
-#define CDBGRSTREQ (1 << 26)
-#define CDBGRSTACK (1 << 27)
-#define CDBGPWRUPREQ (1 << 28)
-#define CDBGPWRUPACK (1 << 29)
-#define CSYSPWRUPREQ (1 << 30)
-#define CSYSPWRUPACK (1 << 31)
-
-#define AP_REG_CSW 0x00
+
+#define BANK_REG(bank, reg) (((bank) << 4) | (reg))
+
+/* A[3:0] for DP registers; A[1:0] are always zero.
+ * - JTAG accesses all of these via JTAG_DP_DPACC, except for
+ * IDCODE (JTAG_DP_IDCODE) and ABORT (JTAG_DP_ABORT).
+ * - SWD accesses these directly, sometimes needing SELECT.CTRLSEL
+ */
+#define DP_IDCODE BANK_REG(0x0, 0x0) /* SWD: read */
+#define DP_ABORT BANK_REG(0x0, 0x0) /* SWD: write */
+#define DP_CTRL_STAT BANK_REG(0x0, 0x4) /* r/w */
+#define DP_RESEND BANK_REG(0x0, 0x8) /* SWD: read */
+#define DP_SELECT BANK_REG(0x0, 0x8) /* JTAG: r/w; SWD: write */
+#define DP_RDBUFF BANK_REG(0x0, 0xC) /* read-only */
+#define DP_WCR BANK_REG(0x1, 0x4) /* SWD: r/w */
+
+#define WCR_TO_TRN(wcr) ((uint32_t)(1 + (3 & ((wcr)) >> 8))) /* 1..4 clocks */
+#define WCR_TO_PRESCALE(wcr) ((uint32_t)(7 & ((wcr)))) /* impl defined */
+
+/* Fields of the DP's AP ABORT register */
+#define DAPABORT (1UL << 0)
+#define STKCMPCLR (1UL << 1) /* SWD-only */
+#define STKERRCLR (1UL << 2) /* SWD-only */
+#define WDERRCLR (1UL << 3) /* SWD-only */
+#define ORUNERRCLR (1UL << 4) /* SWD-only */
+
+/* Fields of the DP's CTRL/STAT register */
+#define CORUNDETECT (1UL << 0)
+#define SSTICKYORUN (1UL << 1)
+/* 3:2 - transaction mode (e.g. pushed compare) */
+#define SSTICKYCMP (1UL << 4)
+#define SSTICKYERR (1UL << 5)
+#define READOK (1UL << 6) /* SWD-only */
+#define WDATAERR (1UL << 7) /* SWD-only */
+/* 11:8 - mask lanes for pushed compare or verify ops */
+/* 21:12 - transaction counter */
+#define CDBGRSTREQ (1UL << 26)
+#define CDBGRSTACK (1UL << 27)
+#define CDBGPWRUPREQ (1UL << 28)
+#define CDBGPWRUPACK (1UL << 29)
+#define CSYSPWRUPREQ (1UL << 30)
+#define CSYSPWRUPACK (1UL << 31)
+
+/* MEM-AP register addresses */
+/* TODO: rename as MEM_AP_REG_* */
+#define AP_REG_CSW 0x00