Debug: Add PyCortexDebug. Core and peripheral register database and decoder. (#251)

* Debug: pycortexdebug
* Debug: format PyCortexMDebug source code

debug/PyCortexMDebug/cmdebug/dwt_gdb.py

@@ -0,0 +1,152 @@
+#!/usr/bin/env python
+"""
+This file is part of PyCortexMDebug
+
+PyCortexMDebug 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 3 of the License, or
+(at your option) any later version.
+
+PyCortexMDebug 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 PyCortexMDebug.  If not, see <http://www.gnu.org/licenses/>.
+"""
+
+import gdb
+import struct
+
+DWT_CTRL = 0xE0001000
+DWT_CYCCNT = 0xE0001004
+DWT_CPICNT = 0xE0001008
+DWT_EXTCNT = 0xE000100C
+DWT_SLEEPCNT = 0xE0001010
+DWT_LSUCNT = 0xE0001014
+DWT_FOLDCNT = 0xE0001018
+DWT_PCSR = 0xE000101C
+
+prefix = "dwt : "
+
+
+class DWT(gdb.Command):
+    clk = None
+    is_init = False
+
+    def __init__(self):
+        gdb.Command.__init__(self, "dwt", gdb.COMMAND_DATA)
+
+    def read(self, address, bits=32):
+        """Read from memory (using print) and return an integer"""
+        value = gdb.selected_inferior().read_memory(address, bits / 8)
+        return struct.unpack_from("<i", value)[0]
+
+    def write(self, address, value, bits=32):
+        """Set a value in memory"""
+        gdb.selected_inferior().write_memory(address, bytes(value), bits / 8)
+
+    def invoke(self, args, from_tty):
+        if not self.is_init:
+            self.write(0xE000EDFC, self.read(0xE000EDFC) | (1 << 24))
+            self.write(DWT_CTRL, 0)
+            self.is_init = True
+
+        s = map(lambda x: x.lower(), str(args).split(" "))
+        # Check for empty command
+        if s[0] in ["", "help"]:
+            self.print_help()
+            return ()
+
+        if s[0] == "cyccnt":
+            if len(s) > 1:
+                if s[1][:2] == "en":
+                    self.cyccnt_en()
+                elif s[1][0] == "r":
+                    self.cyccnt_reset()
+                elif s[1][0] == "d":
+                    self.cyccnt_dis()
+            gdb.write(
+                prefix
+                + "CYCCNT ({}): ".format("ON" if (self.read(DWT_CTRL) & 1) else "OFF")
+                + self.cycles_str(self.read(DWT_CYCCNT))
+            )
+        elif s[0] == "reset":
+            if len(s) > 1:
+                if s[1] == "cyccnt":
+                    self.cyccnt_reset()
+                    gdb.write(prefix + "CYCCNT reset\n")
+                if s[1] == "counters":
+                    self.cyccnt_reset()
+                    gdb.write(prefix + "CYCCNT reset\n")
+                else:
+                    self.cyccnt_reset()
+                    gdb.write(prefix + "CYCCNT reset\n")
+            else:
+                # Reset everything
+                self.cyccnt_reset()
+                gdb.write(prefix + "CYCCNT reset\n")
+        elif s[0] == "configclk":
+            if len(s) == 2:
+                try:
+                    self.clk = float(s[1])
+                except:
+                    self.print_help()
+            else:
+                self.print_help()
+        else:
+            # Try to figure out what stupid went on here
+            gdb.write(args)
+            self.print_help()
+
+    def complete(self, text, word):
+        text = str(text).lower()
+        s = text.split(" ")
+
+        commands = ["configclk", "reset", "cyccnt"]
+        reset_commands = ["counters", "cyccnt"]
+        cyccnt_commands = ["enable", "reset", "disable"]
+
+        if len(s) == 1:
+            return filter(lambda x: x.startswith(s[0]), commands)
+
+        if len(s) == 2:
+            if s[0] == "reset":
+                return filter(lambda x: x.startswith(s[1]), reset_commands)
+            if s[0] == "cyccnt":
+                return filter(lambda x: x.startswith(s[1]), cyccnt_commands)
+
+    def cycles_str(self, cycles):
+        if self.clk:
+            return "%d cycles, %.3es\n" % (cycles, cycles * 1.0 / self.clk)
+        else:
+            return "%d cycles"
+
+    def cyccnt_en(self):
+        self.write(DWT_CTRL, self.read(DWT_CTRL) | 1)
+
+    def cyccnt_dis(self):
+        self.write(DWT_CTRL, self.read(DWT_CTRL) & 0xFFFFFFFE)
+
+    def cyccnt_reset(self, value=0):
+        self.write(DWT_CYCCNT, value)
+
+    def cpicnt_reset(self, value=0):
+        self.write(DWT_CPICNT, value & 0xFF)
+
+    def print_help(self):
+        gdb.write("Usage:\n")
+        gdb.write("=========\n")
+        gdb.write("dwt:\n")
+        gdb.write("\tList available peripherals\n")
+        gdb.write("dwt configclk [Hz]:\n")
+        gdb.write("\tSet clock for rendering time values in seconds\n")
+        gdb.write("dwt reset:\n")
+        gdb.write("\tReset everything in DWT\n")
+        gdb.write("dwt reset counters:\n")
+        gdb.write("\tReset all DWT counters\n")
+        gdb.write("dwt cyccnt\n")
+        gdb.write("\tDisplay the cycle count\n")
+        gdb.write("\td(default):decimal, x: hex, o: octal, b: binary\n")
+        return ()