[openocd.git] / src / jtag / jtag.h

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/
#ifndef JTAG_H
#define JTAG_H

#include "types.h"
#include "binarybuffer.h"
#include "log.h"

#include "command.h"

#if 0
#define _DEBUG_JTAG_IO_
#endif

/* Tap States
 * TLR - Test-Logic-Reset, RTI - Run-Test/Idle, 
 * SDS - Select-DR-Scan, CD - Capture-DR, SD - Shift-DR, E1D - Exit1-DR,
 * PD - Pause-DR, E2D - Exit2-DR, UD - Update-DR,
 * SIS - Select-IR-Scan, CI - Capture-IR, SI - Shift-IR, E1I - Exit1-IR,
 * PI - Pause-IR, E2I - Exit2-IR, UI - Update-IR 
 */
enum tap_state
{
        TAP_TLR = 0x0, TAP_RTI = 0x8, 
        TAP_SDS = 0x1, TAP_CD = 0x2, TAP_SD = 0x3, TAP_E1D = 0x4, 
        TAP_PD = 0x5, TAP_E2D = 0x6, TAP_UD = 0x7,
        TAP_SIS = 0x9, TAP_CI = 0xa, TAP_SI = 0xb, TAP_E1I = 0xc,
        TAP_PI = 0xd, TAP_E2I = 0xe, TAP_UI = 0xf
};

typedef struct tap_transition_s
{
        enum tap_state high;
        enum tap_state low;
} tap_transition_t;

extern char* tap_state_strings[16];
extern int tap_move_map[16];    /* map 16 TAP states to 6 stable states */
extern u8 tap_move[6][6];               /* value scanned to TMS to move from one of six stable states to another */
extern tap_transition_t tap_transitions[16];    /* describe the TAP state diagram */

extern enum tap_state end_state;                /* finish DR scans in dr_end_state */
extern enum tap_state cur_state;                /* current TAP state */

extern enum tap_state cmd_queue_end_state;              /* finish DR scans in dr_end_state */
extern enum tap_state cmd_queue_cur_state;              /* current TAP state */

#define TAP_MOVE(from, to) tap_move[tap_move_map[from]][tap_move_map[to]]

typedef void * error_handler_t; /* Later on we can delete error_handler_t, but keep it for now to make patches more readable */

struct scan_field_s;
typedef int (*in_handler_t)(u8 *in_value, void *priv, struct scan_field_s *field);

typedef struct scan_field_s
{
        int device;                     /* ordinal device number this instruction refers to */
        int num_bits;           /* number of bits this field specifies (up to 32) */
        u8 *out_value;          /* value to be scanned into the device */
        u8 *out_mask;           /* only masked bits care */
        u8 *in_value;           /* pointer to a 32-bit memory location to take data scanned out */
        /* in_check_value/mask, in_handler_error_handler, in_handler_priv can be used by the in handler, otherwise they contain garbage  */
        u8 *in_check_value;     /* used to validate scan results */ 
        u8 *in_check_mask;      /* check specified bits against check_value */
        in_handler_t in_handler;            /* process received buffer using this handler */
        void *in_handler_priv;  /* additional information for the in_handler */
} scan_field_t;


enum scan_type
{
        /* IN: from device to host, OUT: from host to device */
        SCAN_IN = 1, SCAN_OUT = 2, SCAN_IO = 3
};

typedef struct scan_command_s
{
        int ir_scan;    /* instruction/not data scan */
        int num_fields;         /* number of fields in *fields array */
        scan_field_t *fields;   /* pointer to an array of data scan fields */
        enum tap_state end_state;       /* TAP state in which JTAG commands should finish */
} scan_command_t;

typedef struct statemove_command_s
{
        enum tap_state end_state;       /* TAP state in which JTAG commands should finish */
} statemove_command_t;

typedef struct pathmove_command_s
{
        int num_states;                         /* number of states in *path */
        enum tap_state *path;           /* states that have to be passed */
} pathmove_command_t;

typedef struct runtest_command_s
{
        int num_cycles;         /* number of cycles that should be spent in Run-Test/Idle */
        enum tap_state end_state;       /* TAP state in which JTAG commands should finish */
} runtest_command_t;

typedef struct reset_command_s
{
        int trst;                       /* trst/srst 0: deassert, 1: assert, -1: don't change */
        int srst;
} reset_command_t;

typedef struct end_state_command_s
{
        enum tap_state end_state;       /* TAP state in which JTAG commands should finish */
} end_state_command_t;

typedef struct sleep_command_s
{
        u32 us;         /* number of microseconds to sleep */
} sleep_command_t;

typedef union jtag_command_container_u
{
        scan_command_t *scan;
        statemove_command_t *statemove;
        pathmove_command_t *pathmove;
        runtest_command_t *runtest;
        reset_command_t *reset;
        end_state_command_t *end_state;
        sleep_command_t *sleep;
} jtag_command_container_t;

enum jtag_command_type
{
        JTAG_SCAN = 1,
        JTAG_STATEMOVE = 2, JTAG_RUNTEST = 3,
        JTAG_RESET = 4, JTAG_END_STATE = 5,
        JTAG_PATHMOVE = 6, JTAG_SLEEP = 7
};

typedef struct jtag_command_s
{
        jtag_command_container_t cmd;
        enum jtag_command_type type;
        struct jtag_command_s *next;
} jtag_command_t;

extern jtag_command_t *jtag_command_queue;

typedef struct jtag_device_s
{
        int ir_length;          /* size of instruction register */
        u8 *expected;           /* Capture-IR expected value */
        u8 *expected_mask;      /* Capture-IR expected mask */
        u32 idcode;                     /* device identification code */
        u8 *cur_instr;          /* current instruction */
        int bypass;                     /* bypass register selected */
        struct jtag_device_s *next;
} jtag_device_t;

extern jtag_device_t *jtag_devices;
extern int jtag_num_devices;
extern int jtag_ir_scan_size;

enum reset_line_mode
{
        LINE_OPEN_DRAIN = 0x0,
        LINE_PUSH_PULL = 0x1,
};

typedef struct jtag_interface_s
{
        char* name;
        
        /* queued command execution
         */
        int (*execute_queue)(void);
        
        /* interface initalization
         */
        int (*speed)(int speed);
        int (*register_commands)(struct command_context_s *cmd_ctx);
        int (*init)(void);
        int (*quit)(void);
        /* returns JTAG maxium speed for KHz. 0=RTCK. The function returns
        a failure if it can't support the KHz/RTCK. */
        int (*khz)(int khz, int *jtag_speed);
        
} jtag_interface_t;

enum jtag_event
{
        JTAG_TRST_ASSERTED
};

extern char* jtag_event_strings[];

extern int jtag_trst;
extern int jtag_srst;

typedef struct jtag_event_callback_s
{
        int (*callback)(enum jtag_event event, void *priv);
        void *priv;
        struct jtag_event_callback_s *next;
} jtag_event_callback_t;

extern jtag_event_callback_t *jtag_event_callbacks;

extern jtag_interface_t *jtag;  /* global pointer to configured JTAG interface */
extern enum tap_state end_state;
extern enum tap_state cur_state;

extern int jtag_speed;
extern int jtag_speed_post_reset;

enum reset_types
{
        RESET_NONE = 0x0, 
        RESET_HAS_TRST = 0x1, 
        RESET_HAS_SRST = 0x2, 
        RESET_TRST_AND_SRST = 0x3, 
        RESET_SRST_PULLS_TRST = 0x4,
        RESET_TRST_PULLS_SRST = 0x8,
        RESET_TRST_OPEN_DRAIN = 0x10,
        RESET_SRST_PUSH_PULL = 0x20,
};

extern enum reset_types jtag_reset_config;

/* initialize interface upon startup. A successful no-op 
 * upon subsequent invocations
 */
extern int jtag_interface_init(struct command_context_s *cmd_ctx);
/* initialize JTAG chain using only a TLR reset. If init fails,
 * try reset + init.
 */
extern int jtag_init(struct command_context_s *cmd_ctx);
/* reset, then initialize JTAG chain */
extern int jtag_init_reset(struct command_context_s *cmd_ctx);
extern int jtag_register_commands(struct command_context_s *cmd_ctx);

/* JTAG interface, can be implemented with a software or hardware fifo
 * 
 * TAP_SD and TAP_SI are illegal end states. TAP_SD/SI as end states
 * can be emulated by using a larger scan.
 *
 * Code that is relatively insensitive to the path(as long
 * as it is JTAG compliant) taken through state machine can use 
 * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be 
 * specified as end state and a subsequent jtag_add_pathmove() must 
 * be issued. 
 *
 */
extern void jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern void jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern int interface_jtag_add_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
/* run a TAP_TLR reset. End state is TAP_TLR, regardless
 * of start state.
 */
extern void jtag_add_tlr();
extern int interface_jtag_add_tlr();
/* Do not use jtag_add_pathmove() unless you need to, but do use it
 * if you have to. 
 *
 * DANGER! If the target is dependent upon a particular sequence
 * of transitions for things to work correctly(e.g. as a workaround 
 * for an errata that contradicts the JTAG standard), then pathmove 
 * must be used, even if some jtag interfaces happen to use the 
 * desired path. Worse, the jtag interface used for testing a 
 * particular implementation, could happen to use the "desired" 
 * path when transitioning to/from end
 * state.
 *
 * A list of unambigious single clock state transitions, not
 * all drivers can support this, but it is required for e.g.
 * XScale and Xilinx support
 * 
 * Note! TAP_TLR must not be used in the path!
 * 
 * Note that the first on the list must be reachable 
 * via a single transition from the current state. 
 *
 * All drivers are required to implement jtag_add_pathmove().
 * However, if the pathmove sequence can not be precisely
 * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
 * must return an error. It is legal, but not recommended, that
 * a driver returns an error in all cases for a pathmove if it
 * can only implement a few transitions and therefore
 * a partial implementation of pathmove would have little practical
 * application.
 */
extern void jtag_add_pathmove(int num_states, enum tap_state *path);
extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);
/* go to TAP_RTI, if we're not already there and cycle
 * precisely num_cycles in the TAP_RTI after which move
 * to the end state, if it is != TAP_RTI
 */
extern void jtag_add_runtest(int num_cycles, enum tap_state endstate);
extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate);
/* A reset of the TAP state machine can be requested.
 * 
 * Whether tms or trst reset is used depends on the capabilities of 
 * the target and jtag interface(reset_config  command configures this).
 * 
 * srst can driver a reset of the TAP state machine and vice
 * versa
 * 
 * Application code may need to examine value of jtag_reset_config
 * to determine the proper codepath
 * 
 * DANGER! Even though srst drives trst, trst might not be connected to
 * the interface, and it might actually be *harmful* to assert trst in this case.
 * 
 * This is why combinations such as "reset_config srst_only srst_pulls_trst"
 * are supported. 
 *
 * only req_tlr_or_trst and srst can have a transition for a
 * call as the effects of transitioning both at the "same time" 
 * are undefined, but when srst_pulls_trst or vice versa,
 * then trst & srst *must* be asserted together.
 */
extern void jtag_add_reset(int req_tlr_or_trst, int srst);
/* this drives the actual srst and trst pins. srst will always be 0
 * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
 * trst.
 * 
 * the higher level jtag_add_reset will invoke jtag_add_tlr() if 
 * approperiate
 */
extern int interface_jtag_add_reset(int trst, int srst);
extern void jtag_add_end_state(enum tap_state endstate);
extern int interface_jtag_add_end_state(enum tap_state endstate);
extern void jtag_add_sleep(u32 us);
extern int interface_jtag_add_sleep(u32 us);



/*
 * For software FIFO implementations, the queued commands can be executed 
 * during this call or earlier. A sw queue might decide to push out
 * some of the jtag_add_xxx() operations once the queue is "big enough".
 * 
 * This fn will return an error code if any of the prior jtag_add_xxx() 
 * calls caused a failure, e.g. check failure. Note that it does not
 * matter if the operation was executed *before* jtag_execute_queue(),
 * jtag_execute_queue() will still return an error code. 
 * 
 * All jtag_add_xxx() calls that have in_handler!=NULL will have been
 * executed when this fn returns, but if what has been queued only 
 * clocks data out, without reading anything back, then JTAG could 
 * be running *after* jtag_execute_queue() returns. The API does 
 * not define a way to flush a hw FIFO that runs *after* 
 * jtag_execute_queue() returns. 
 * 
 * jtag_add_xxx() commands can either be executed immediately or 
 * at some time between the jtag_add_xxx() fn call and jtag_execute_queue().  
 */
extern int jtag_execute_queue(void);
/* can be implemented by hw+sw */
extern int interface_jtag_execute_queue(void);

/* JTAG support functions */
extern void jtag_set_check_value(scan_field_t *field, u8 *value,  u8 *mask, error_handler_t *in_error_handler);
extern enum scan_type jtag_scan_type(scan_command_t *cmd);
extern int jtag_scan_size(scan_command_t *cmd);
extern int jtag_read_buffer(u8 *buffer, scan_command_t *cmd);
extern int jtag_build_buffer(scan_command_t *cmd, u8 **buffer);
extern jtag_device_t* jtag_get_device(int num);
extern void jtag_sleep(u32 us);
extern int jtag_call_event_callbacks(enum jtag_event event);
extern int jtag_register_event_callback(int (*callback)(enum jtag_event event, void *priv), void *priv);

extern int jtag_verify_capture_ir;

/* error codes
 * JTAG subsystem uses codes between -100 and -199 */

#define ERROR_JTAG_INIT_FAILED                  (-100)
#define ERROR_JTAG_INVALID_INTERFACE    (-101)
#define ERROR_JTAG_NOT_IMPLEMENTED              (-102)
#define ERROR_JTAG_TRST_ASSERTED                (-103)
#define ERROR_JTAG_QUEUE_FAILED                 (-104)
#define ERROR_JTAG_DEVICE_ERROR                 (-107)



/* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
#ifdef HAVE_JTAG_MINIDRIVER_H
/* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
#include "jtag_minidriver.h"
#define MINIDRIVER(a) notused ## a 
#else
#define MINIDRIVER(a) a
/* jtag_add_dr_out() is a faster version of jtag_add_dr_scan() 
 * 
 * Current or end_state can not be TAP_TLR. end_state can be -1
 * 
 * num_bits[i] is the number of bits to clock out from value[i] LSB first.
 * 
 * If the device is in bypass, then that is an error condition in
 * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
 * does detect it. Similarly if the device is not in bypass, data must
 * be passed to it. 
 * 
 * If anything fails, then jtag_error will be set and jtag_execute() will
 * return an error. There is no way to determine if there was a failure
 * during this function call.
 * 
 * Note that this jtag_add_dr_out can be defined as an inline function.
 */
extern void interface_jtag_add_dr_out(int device, 
                int num_fields,
                int *num_bits,
                u32 *value,
                enum tap_state end_state);
#endif




static __inline__ void jtag_add_dr_out(int device, 
                int num_fields,
                int *num_bits,
                u32 *value,
                enum tap_state end_state)
{
        if (end_state != -1)
                cmd_queue_end_state=end_state;
        cmd_queue_cur_state=cmd_queue_end_state;
        interface_jtag_add_dr_out(device, num_fields, num_bits, value, cmd_queue_end_state);
}


#endif /* JTAG_H */