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,