src/target/riscv/batch.h

   1 #ifndef TARGET__RISCV__SCANS_H
   2 #define TARGET__RISCV__SCANS_H
   3
   4 #include "target/target.h"
   5 #include "jtag/jtag.h"
   6
   7 enum riscv_scan_type {
   8         RISCV_SCAN_TYPE_INVALID,
   9         RISCV_SCAN_TYPE_NOP,
  10         RISCV_SCAN_TYPE_READ,
  11         RISCV_SCAN_TYPE_WRITE,
  12 };
  13
  14 /* A batch of multiple JTAG scans, which are grouped together to avoid the
  15  * overhead of some JTAG adapters when sending single commands.  This is
  16  * designed to support block copies, as that's what we actually need to go
  17  * fast. */
  18 struct riscv_batch {
  19         struct target *target;
  20
  21         size_t allocated_scans;
  22         size_t used_scans;
  23
  24         size_t idle_count;
  25
  26         uint8_t *data_out;
  27         uint8_t *data_in;
  28         struct scan_field *fields;
  29
  30         /* In JTAG we scan out the previous value's output when performing a
  31          * scan.  This is a pain for users, so we just provide them the
  32          * illusion of not having to do this by eliding all but the last NOP.
  33          * */
  34         enum riscv_scan_type last_scan;
  35
  36         /* The read keys. */
  37         size_t *read_keys;
  38         size_t read_keys_used;
  39 };
  40
  41 /* Allocates (or frees) a new scan set.  "scans" is the maximum number of JTAG
  42  * scans that can be issued to this object, and idle is the number of JTAG idle
  43  * cycles between every real scan. */
  44 struct riscv_batch *riscv_batch_alloc(struct target *target, size_t scans, size_t idle);
  45 void riscv_batch_free(struct riscv_batch *batch);
  46
  47 /* Checks to see if this batch is full. */
  48 bool riscv_batch_full(struct riscv_batch *batch);
  49
  50 /* Executes this scan batch. */
  51 int riscv_batch_run(struct riscv_batch *batch);
  52
  53 /* Adds a DMI write to this batch. */
  54 void riscv_batch_add_dmi_write(struct riscv_batch *batch, unsigned address, uint64_t data);
  55
  56 /* DMI reads must be handled in two parts: the first one schedules a read and
  57  * provides a key, the second one actually obtains the value of that read .*/
  58 size_t riscv_batch_add_dmi_read(struct riscv_batch *batch, unsigned address);
  59 uint64_t riscv_batch_get_dmi_read(struct riscv_batch *batch, size_t key);
  60
  61 /* Scans in a NOP. */
  62 void riscv_batch_add_nop(struct riscv_batch *batch);
  63
  64 #endif