#define JTAG_DP_APACC 0xB
#define JTAG_DP_IDCODE 0xE
+/* three-bit ACK values for DPACC and APACC reads */
+#define JTAG_ACK_OK_FAULT 0x2
+#define JTAG_ACK_WAIT 0x1
+
+/* three-bit ACK values for SWD access (sent LSB first) */
+#define SWD_ACK_OK 0x4
+#define SWD_ACK_WAIT 0x2
+#define SWD_ACK_FAULT 0x1
+
#define DPAP_WRITE 0
#define DPAP_READ 1
-/* A[3:0] for DP registers (for JTAG, stored in DPACC) */
-#define DP_ZERO 0
-#define DP_CTRL_STAT 0x4
-#define DP_SELECT 0x8
-#define DP_RDBUFF 0xC
+/* 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 0 /* SWD: read */
+#define DP_ABORT 0 /* SWD: write */
+#define DP_CTRL_STAT 0x4 /* r/w */
+#define DP_WCR 0x4 /* SWD: r/w (mux CTRLSEL) */
+#define DP_RESEND 0x8 /* SWD: read */
+#define DP_SELECT 0x8 /* JTAG: r/w; SWD: write */
+#define DP_RDBUFF 0xC /* read-only */
+
+/* Fields of the DP's AP ABORT register */
+#define DAPABORT (1 << 0)
+#define STKCMPCLR (1 << 1) /* SWD-only */
+#define STKERRCLR (1 << 2) /* SWD-only */
+#define WDERRCLR (1 << 3) /* SWD-only */
+#define ORUNERRCLR (1 << 4) /* SWD-only */
/* Fields of the DP's CTRL/STAT register */
#define CORUNDETECT (1 << 0)
#define SSTICKYORUN (1 << 1)
/* 3:2 - transaction mode (e.g. pushed compare) */
+#define SSTICKYCMP (1 << 4)
#define SSTICKYERR (1 << 5)
-#define READOK (1 << 6)
-#define WDATAERR (1 << 7)
+#define READOK (1 << 6) /* SWD-only */
+#define WDATAERR (1 << 7) /* SWD-only */
/* 11:8 - mask lanes for pushed compare or verify ops */
/* 21:12 - transaction counter */
#define CDBGRSTREQ (1 << 26)
struct arm_jtag *jtag_info;
/* Control config */
uint32_t dp_ctrl_stat;
- /* Support for several AP's in one DAP */
+
+ /**
+ * Cache for DP_SELECT bits identifying the current AP. A DAP may
+ * connect to multiple APs, such as one MEM-AP for general access,
+ * another reserved for accessing debug modules, and a JTAG-DP.
+ * "-1" indicates no cached value.
+ */
uint32_t apsel;
- /* Register select cache */
- uint32_t dp_select_value;
+
+ /**
+ * Cache for DP_SELECT bits identifying the current four-word AP
+ * register bank. This caches AP register addresss bits 7:4; JTAG
+ * and SWD access primitves pass address bits 3:2; bits 1:0 are zero.
+ * "-1" indicates no cached value.
+ */
+ uint32_t ap_bank_value;
+
+ /**
+ * Cache for (MEM-AP) AP_REG_CSW register value. This is written to
+ * configure an access mode, such as autoincrementing AP_REG_TAR during
+ * word access. "-1" indicates no cached value.
+ */
uint32_t ap_csw_value;
+
+ /**
+ * Cache for (MEM-AP) AP_REG_TAR register value This is written to
+ * configure the address being read or written
+ * "-1" indicates no cached value.
+ */
uint32_t ap_tar_value;
+
/* information about current pending SWjDP-AHBAP transaction */
uint8_t trans_mode;
uint8_t trans_rw;
uint8_t ack;
- /* extra tck clocks for memory bus access */
+ /**
+ * Configures how many extra tck clocks are added after starting a
+ * MEM-AP access before we try to read its status (and/or result).
+ */
uint32_t memaccess_tck;
/* Size of TAR autoincrement block, ARM ADI Specification requires at least 10 bits */
uint32_t tar_autoincr_block;
};
-/* Accessor function for currently selected DAP-AP number */
+/** Accessor for currently selected DAP-AP number (0..255) */
static inline uint8_t dap_ap_get_select(struct swjdp_common *swjdp)
{
return (uint8_t)(swjdp ->apsel >> 24);
}
-/* Queued transactions -- use with care */
+/* AP selection applies to future AP transactions */
+void dap_ap_select(struct swjdp_common *dap,uint8_t apsel);
+
+/* AP transactions ... synchronous given TRANS_MODE_ATOMIC */
int dap_setup_accessport(struct swjdp_common *swjdp,
uint32_t csw, uint32_t tar);
-int dap_ap_select(struct swjdp_common *swjdp,uint8_t apsel);
int dap_ap_write_reg_u32(struct swjdp_common *swjdp,
uint32_t addr, uint32_t value);
int dap_ap_read_reg_u32(struct swjdp_common *swjdp,
uint32_t addr, uint32_t *value);
-/* Queued transactions must be completed with swjdp_transaction_endcheck() */
-int swjdp_transaction_endcheck(struct swjdp_common *swjdp);
+/* Queued JTAG ops must be completed with jtagdp_transaction_endcheck() */
+int jtagdp_transaction_endcheck(struct swjdp_common *swjdp);
-/* MEM-AP memory mapped bus single uint32_t register transfers, without endcheck */
+/* Queued MEM-AP memory mapped single word transfers */
int mem_ap_read_u32(struct swjdp_common *swjdp, uint32_t address, uint32_t *value);
int mem_ap_write_u32(struct swjdp_common *swjdp, uint32_t address, uint32_t value);
-/* MEM-AP memory mapped bus transfers, single registers, complete transactions */
+/* Synchronous MEM-AP memory mapped single word transfers */
int mem_ap_read_atomic_u32(struct swjdp_common *swjdp,
uint32_t address, uint32_t *value);
int mem_ap_write_atomic_u32(struct swjdp_common *swjdp,