From 4a55374a35da5c7961facf90e178353a15c6d614 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Sat, 10 Oct 2020 15:13:38 +0100
Subject: [PATCH] add first version of firmware uploader

---
 src/soc/debug/firmware_upload.py | 140 +++++++++++++++++++++++++++++++
 1 file changed, 140 insertions(+)
 create mode 100644 src/soc/debug/firmware_upload.py

diff --git a/src/soc/debug/firmware_upload.py b/src/soc/debug/firmware_upload.py
new file mode 100644
index 00000000..5fe2c4ca
--- /dev/null
+++ b/src/soc/debug/firmware_upload.py
@@ -0,0 +1,140 @@
+"""JTAG Wishbone firmware upload program
+
+to test, run "python3 debug/test/test_jtag_tap_srv.py server"
+
+"""
+
+import sys
+from nmigen import (Module, Signal, Elaboratable, Const)
+from c4m.nmigen.jtag.tap import TAP, IOType
+from c4m.nmigen.jtag.bus import Interface as JTAGInterface
+from soc.debug.dmi import DMIInterface, DBGCore
+from soc.debug.test.dmi_sim import dmi_sim
+from soc.debug.jtag import JTAG
+from soc.debug.test.jtagremote import JTAGServer, JTAGClient
+
+from nmigen_soc.wishbone.sram import SRAM
+from nmigen import Memory, Signal, Module
+
+from nmigen.back.pysim import Simulator, Delay, Settle, Tick
+from nmutil.util import wrap
+from soc.debug.jtagutils import (jtag_read_write_reg,
+                                 jtag_srv, jtag_set_reset,
+                                 jtag_set_ir, jtag_set_get_dr)
+
+def test_pinset():
+    return {
+            # in, out, tri-out, tri-inout
+            'test': ['io0-', 'io1+', 'io2>', 'io3*'],
+           }
+
+
+# JTAG-ircodes for accessing DMI
+DMI_ADDR = 8
+DMI_READ = 9
+DMI_WRRD = 10
+
+# JTAG-ircodes for accessing Wishbone
+WB_ADDR = 5
+WB_READ = 6
+WB_WRRD = 7
+
+# JTAG boundary scan reg addresses
+BS_EXTEST = 0
+BS_INTEST = 0
+BS_SAMPLE = 2
+BS_PRELOAD = 2
+
+
+def jtag_sim(dut, firmware):
+
+    ####### JTAGy stuff (IDCODE) ######
+
+    # read idcode
+    yield from jtag_set_reset(dut)
+    idcode = yield from jtag_read_write_reg(dut, 0b1, 32)
+    print ("idcode", hex(idcode))
+    assert idcode == 0x18ff
+
+    ####### JTAG to DMI ######
+
+    # write DMI address
+    yield from jtag_read_write_reg(dut, DMI_ADDR, 8, DBGCore.CTRL)
+
+    # read DMI CTRL register
+    status = yield from jtag_read_write_reg(dut, DMI_READ, 64)
+    print ("dmi ctrl status", hex(status))
+    assert status == 4
+
+    # write DMI address
+    yield from jtag_read_write_reg(dut, DMI_ADDR, 8, 0)
+
+    # write DMI CTRL register
+    status = yield from jtag_read_write_reg(dut, DMI_WRRD, 64, 0b101)
+    print ("dmi ctrl status", hex(status))
+    assert status == 4 # returned old value (nice! cool feature!)
+
+    # write DMI address
+    yield from jtag_read_write_reg(dut, DMI_ADDR, 8, DBGCore.CTRL)
+
+    # read DMI CTRL register
+    status = yield from jtag_read_write_reg(dut, DMI_READ, 64)
+    print ("dmi ctrl status", hex(status))
+    assert status == 5
+
+    # write DMI MSR address
+    yield from jtag_read_write_reg(dut, DMI_ADDR, 8, DBGCore.MSR)
+
+    # read DMI MSR register
+    msr = yield from jtag_read_write_reg(dut, DMI_READ, 64)
+    print ("dmi msr", hex(msr))
+    assert msr == 0xdeadbeef
+
+    ####### JTAG to Wishbone ######
+
+    # write Wishbone address
+    yield from jtag_read_write_reg(dut, WB_ADDR, 64, 0)
+
+    # write/read wishbone data
+    for val in firmware:
+        data = yield from jtag_read_write_reg(dut, WB_WRRD, 64, val)
+        print ("wb write", hex(data))
+
+    # write Wishbone address
+    yield from jtag_read_write_reg(dut, WB_ADDR, 64, 0)
+
+    # confirm data written
+    for val in firmware:
+        data = yield from jtag_read_write_reg(dut, WB_READ, 64, 0)
+        print ("wb read", hex(data))
+
+    ####### done - tell dmi_sim to stop (otherwise it won't) ########
+
+    print ("jtag sim stopping")
+
+
+if __name__ == '__main__':
+    # rather than the client access the JTAG bus directly
+    # create an alternative that the client sets
+    class Dummy: pass
+    cdut = Dummy()
+    cdut.cbus = JTAGInterface()
+
+    # set up client-server on port 44843-something
+    cdut.c = JTAGClient()
+
+    # take copy of ir_width and scan_len
+    cdut._ir_width = 4
+
+    flag = Signal()
+    m = Module()
+    m.d.sync += flag.eq(~flag) # get us a "sync" domain
+
+    sim = Simulator(m)
+    sim.add_clock(1e-6, domain="sync")      # standard clock
+
+    data = [0x01, 0x02] # list of 64-bit words
+    sim.add_sync_process(wrap(jtag_sim(cdut, data))) 
+
+    with sim.write_vcd("jtag_firmware_upload.vcd"):
+        sim.run()
-- 
2.30.2