PyCortexMDebug/cmdebug/svd.py

"""
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 lxml.objectify as objectify
import sys
from copy import deepcopy
from collections import OrderedDict
import os
import traceback

class SVDNonFatalError(Exception):
	""" Exception class for non-fatal errors
	So far, these have related to quirks in some vendor SVD files which are reasonable to ignore
	"""
	def __init__(self, m):
		self.m = m
		self.exc_info = sys.exc_info()

	def __str__(self):
		s = "Non-fatal: {}".format(self.m)
		s += "\n" + str("".join(traceback.format_exc())).strip()
		return s

from cmdebug.svd_debug import show_last_exception

class SVDFile:
	def __init__(self, fname):
		f = objectify.parse(os.path.expanduser(fname))
		root = f.getroot()
		self.peripherals = OrderedDict()
		# XML elements
		for p in root.peripherals.iterchildren(tag='peripheral'):
			try:
				self.peripherals[str(p.name)] = SVDPeripheral(p, self)
			except SVDNonFatalError as e:
				print(e)

def add_register(parent, node):
	if hasattr(node, "dim"):
		dim = int(str(node.dim), 0)
		# dimension is not used, number of split indexes should be same
		incr = int(str(node.dimIncrement), 0)
		default_dim_index = ",".join((str(i) for i in range(dim)))
		dim_index = str(getattr(node, "dimIndex", default_dim_index))
		indexes = dim_index.split(',')
		offset = 0
		for i in indexes:
			name = str(node.name) % i;
			reg = SVDPeripheralRegister(node, parent)
			reg.name = name
			reg.offset += offset
			parent.registers[name] = reg
			offset += incr
	else:
		try:
			parent.registers[str(node.name)] = SVDPeripheralRegister(node, parent)
		except SVDUnsupportedPeriheral:
			pass

def add_cluster(parent, node):
	if hasattr(node, "dim"):
		dim = int(str(node.dim), 0)
		# dimension is not used, number of split indexes should be same
		incr = int(str(node.dimIncrement), 0)
		default_dim_index = ",".join((str(i) for i in range(dim)))
		dim_index = str(getattr(node, "dimIndex", default_dim_index))
		indexes = dim_index.split(',')
		offset = 0
		for i in indexes:
			name = str(node.name) % i;
			cluster = SVDRegisterCluster(node, parent)
			cluster.name = name
			cluster.address_offset += offset
			cluster.base_address += offset
			parent.clusters[name] = cluster
			offset += incr
	else:
		try:
			parent.clusters[str(node.name)] = SVDRegisterCluster(node, parent)
		except SVDUnsupportedPeriheral:
			pass

class SVDRegisterCluster:
	def __init__(self, svd_elem, parent):
		self.parent = parent
		self.address_offset = int(str(svd_elem.addressOffset), 0)
		self.base_address = self.address_offset + parent.base_address
		# This doesn't inherit registers from anything
		children = svd_elem.getchildren()
		self.description = str(svd_elem.description)
		self.name = str(svd_elem.name)
		self.registers = OrderedDict()
		self.clusters = OrderedDict()
		for r in children:
			if r.tag == "register":
				add_register(self, r)

	def refactor_parent(self, parent):
		self.parent = parent
		self.base_address = parent.base_address + self.address_offset
		try:
			values = self.registers.itervalues()
		except AttributeError:
			values = self.registers.values()
		for r in values:
			r.refactor_parent(self)

	def __unicode__(self):
		return str(self.name)

class SVDUnsupportedPeriheral(Exception):
	def __init__(self, elem):
                self.elem = elem

class SVDPeripheral:
	def __init__(self, svd_elem, parent):
		self.parent = parent
		if not hasattr(svd_elem, "baseAddress"):
			raise SVDNonFatalError("Periph without base address")
		self.base_address = int(str(svd_elem.baseAddress), 0)
		if 'derivedFrom' in svd_elem.attrib:
			derived_from = svd_elem.attrib['derivedFrom']
			try:
				self.name = str(svd_elem.name)
			except:
				self.name = parent.peripherals[derived_from].name
			try:
				self.description = str(svd_elem.description)
			except:
				self.description = parent.peripherals[derived_from].description
			self.registers = deepcopy(parent.peripherals[derived_from].registers)
			self.clusters = deepcopy(parent.peripherals[derived_from].clusters)
			self.refactor_parent(parent)
		else:
			# This doesn't inherit registers from anything
			try:
				self.description = str(svd_elem.description)
			except:
				self.description = 'No description provided'
			self.name = str(svd_elem.name)
			self.registers = OrderedDict()
			self.clusters = OrderedDict()

			try:
				registers = svd_elem.registers.getchildren()
				for r in registers:
					if r.tag == "cluster":
						add_cluster(self, r)
					else:
						add_register(self, r)
			except:
				pass

	def refactor_parent(self, parent):
		self.parent = parent
		try:
			values = self.registers.itervalues()
		except AttributeError:
			values = self.registers.values()
		for r in values:
			r.refactor_parent(self)
		try:
			for c in self.clusters.itervalues():
				c.refactor_parent(self)
		except AttributeError:
			for c in self.clusters.values():
				c.refactor_parent(self)

	def __repr__(self):
		return self.name


class SVDPeripheralRegister:
	def __init__(self, svd_elem, parent):
		self.parent = parent
		self.name = str(svd_elem.name)
		self.description = str(svd_elem.description)
		self.offset = int(str(svd_elem.addressOffset),0)
		try:
			self.access = str(svd_elem.access)
		except:
			self.access = "read-write"
		try:
			self.size = int(str(svd_elem.size),0)
		except:
			self.size = 0x20
		self.fields = OrderedDict()
		if hasattr(svd_elem, "fields"):
			fields = svd_elem.fields.getchildren()
			for f in fields:
				self.fields[str(f.name)] = SVDPeripheralRegisterField(f, self)

	def refactor_parent(self, parent):
		self.parent = parent
		try:
			fields = self.fields.itervalues()
		except AttributeError:
			fields = self.fields.values()
		for f in fields:
			f.refactor_parent(self)

	def address(self):
		return self.parent.base_address + self.offset

	def readable(self):
		return self.access in ["read-only", "read-write", "read-writeOnce"]

	def writable(self):
		return self.access in ["write-only", "read-write", "writeOnce", "read-writeOnce"]

	def __unicode__(self):
		return str(self.name)

class SVDPeripheralRegisterField:
	def __init__(self, svd_elem, parent):
		self.parent = parent
		self.name = str(svd_elem.name)
		self.description = str(getattr(svd_elem, "description", ""))

		try:
			self.offset = int(str(svd_elem.bitOffset))
			self.width = int(str(svd_elem.bitWidth))
		except:
			try:
				bitrange = list(map(int, str(svd_elem.bitRange).strip()[1:-1].split(":")))
				self.offset = bitrange[1]
				self.width = 1 + bitrange[0] - bitrange[1]
			except:
				try:
					lsb = int(str(svd_elem.lsb))
					msb = int(str(svd_elem.msb))
					self.offset = lsb
					self.width = 1 + msb - lsb
				except:
					raise SVDUnsupportedPeriheral(svd_elem)
		self.access = str(getattr(svd_elem, "access", parent.access))
		self.enum = {}

		if hasattr(svd_elem, "enumeratedValues"):
			for v in svd_elem.enumeratedValues.getchildren():
				if v.tag == "name":
					continue
				# Some Kinetis parts have values with # instead of 0x...
				value = str(v.value).replace("#","0x")
				self.enum[int(value, 0)] = (str(v.name), str(v.description))

	def refactor_parent(self, parent):
		self.parent = parent

	def readable(self):
		return self.access in ["read-only", "read-write", "read-writeOnce"]

	def writable(self):
		return self.access in ["write-only", "read-write", "writeOnce", "read-writeOnce"]

	def __unicode__(self):
		return str(self.name)

if __name__ == '__main__':
	for f in sys.argv[1:]:
		print("Testing file: {}".format(f))
		svd = SVDFile(f)
		print(svd.peripherals)
		key = list(svd.peripherals)[0]
		print("Registers in peripheral '{}':".format(key))
		print(svd.peripherals[key].registers)
		print("Done testing file: {}".format(f))