3 # Utility to decode register values
4 # Copyright (c) 2006 Jeremy Kerr <jk@ozlabs.org>
5 # Released under the GNU General Public License version 2 or later
7 # Documentation and updates at: http://ozlabs.org/~jk/code/bitfield
12 from pyparsing import Literal, Word, ZeroOrMore, Group, Dict, Optional, \
13 printables, ParseException, restOfLine
14 from getopt import getopt, GetoptError
16 # List of paths to look for configuration files. If a directory is specified,
17 # it will be (recursively) scanned for .conf files.
18 configs = ["/etc/bitfield.d", "/etc/bitfield",
19 os.path.join(os.getenv("HOME"), ".bitfield.d"),
20 os.path.join(os.getenv("HOME"), ".bitfield.conf")]
23 def __init__(self, bits, name):
31 def add_value(self, value, description):
32 self.values[int(value)] = description
34 def mask(self, reg_width, value):
36 out_len = len(self.bits)
37 for out_bit in range(0, out_len):
38 in_bit = self.bits[out_bit]
39 # shift this bit down to the LSB (and mask the rest)
40 i = (value >> (reg_width - in_bit - 1)) & 1
41 # shift back to the output position in the field
42 i <<= out_len - out_bit - 1
46 def value(self, value):
47 if value in self.values:
48 return self.values[value]
52 def mask_and_shift_to_bits(width, mask, shift):
55 for i in range(0, width):
57 bits.append(width - i - 1 - shift)
61 def parse_bitfield(line, reg):
62 a = line.split(None, 1)
68 for s in range_str.split(','):
71 lambda s: reg.bit_number(int(s)),
73 start = reg.bit_number(int(start))
74 end = reg.bit_number(int(end))
75 bits.extend(range(start, end + 1, 1))
77 (mask, shift) = map(lambda s: int(s.strip()),
79 bits.extend(bitfield.mask_and_shift_to_bits( \
80 reg.width, mask, shift))
82 bits.append(reg.bit_number(int(s)))
84 return bitfield(bits, name)
89 def parse_value(line):
90 a = line.split(None, 1)
99 def __init__(self, id):
104 self.bit_order = self.bit_0_is_msb
107 def add_field(self, field):
108 self.fields.append(field)
110 def decode(self, value, ignore_zero):
111 field_width = (self.width + 3) / 4
112 name_width = max(map(lambda f: len(f.name), self.fields))
114 str = "0x%0*lx [%d]\n" % (field_width, value, value)
116 for field in self.fields:
117 v = field.mask(self.width, value);
118 if ignore_zero and v == 0:
120 desc = field.value(v)
122 str += "%*s: 0x%x [%s]\n" \
123 % (name_width, field.name, v, desc)
125 str += "%*s: 0x%x\n" \
126 % (name_width, field.name, v)
129 def bit_number(self, number):
130 if self.bit_order == self.bit_0_is_lsb:
131 number = self.width - 1 - number
135 for (id, r) in regs.iteritems():
136 print "%18s : %s" % (id, r.name)
138 def search_regs(regs, str):
139 return dict((k, regs[k]) for k in regs \
140 if str.lower() in regs[k].name.lower() + k.lower())
142 class ConfigurationError(Exception):
143 def __init__(self, file, message):
145 self.message = message
147 def parse_config(bnf, regs, file):
150 tokens = bnf.parseString(f.read())
152 order_map = {'bit-0-is-lsb': register.bit_0_is_lsb,
153 'bit-0-is-msb': register.bit_0_is_msb,
154 'ibm': register.bit_0_is_msb,
155 'default': register.bit_0_is_msb}
162 raise ConfigurationError(file,
163 "Register %s is already defined" % id)
173 reg.name = name.strip()
174 elif t[0] == 'width':
175 reg.width = int(t[1])
176 elif t[0] == 'field':
177 f = bitfield.parse_bitfield(t[1], reg)
179 raise ConfigurationError(file,
180 "Invalid field in %s" % id)
182 elif t[0] == 'value':
184 raise ConfigurationError(file,
185 "No field for value in %s" % id)
186 v = bitfield.parse_value(t[1])
188 raise ConfigurationError(file,
189 "Invalid value in %s" % id)
191 fields[-1].add_value(v[0], v[1])
192 elif t[0] == 'order':
194 raise ConfigurationError(file,
195 ("bit order defined after " \
196 + "fields in %s") % id)
198 order_str = t[1].strip().lower()
199 order_str = order_str.replace(' ', '-')
201 if order_str not in order_map.keys():
202 raise ConfigurationError(file,
203 "Invalid bit order %s in %s" % \
205 reg.bit_order = order_map[order_str]
207 elif t[0] == 'alias':
208 alias_id = t[1].strip()
210 if alias_id is not None:
211 if reg.name is not None or fields != []:
212 raise ConfigurationError(file, ("Definiton " \
213 + "for %s is an alias, but has other " \
214 + "attributes") % id)
216 if not regs.has_key(alias_id):
217 raise ConfigurationError(file, "Aliasing "
218 "non-existent register %s (from %s)" \
224 if reg.name is None or reg.name == '':
225 raise ConfigurationError(file,
226 "No name for entry %s" % id)
229 raise ConfigurationError(file,
230 "Register %s has no fields" % id)
237 def parse_config_dir(data, dir, fnames):
240 full_fname = os.path.join(dir, fname)
242 if os.path.isdir(full_fname):
245 if fname.endswith('.conf'):
246 parse_config(bnf, regs, full_fname)
248 def parse_all_configs(configs):
251 # set up the bnf to be used for each file
252 lbrack = Literal("[").suppress()
253 rbrack = Literal("]").suppress()
254 colon = Literal(":").suppress()
257 comment = semi + Optional(restOfLine)
259 nonrbrack = "".join([c for c in printables if c != "]"]) + " \t"
260 noncolon = "".join([c for c in printables if c != ":"]) + " \t"
262 sectionDef = lbrack + Word(nonrbrack) + rbrack
263 keyDef = ~lbrack + Word(noncolon) + colon + restOfLine
265 bnf = Dict(ZeroOrMore(Group(sectionDef + ZeroOrMore(Group(keyDef)))))
268 # bundle into a single var that can be passed to os.path.walk
269 conf_data = (bnf, regs)
272 if not os.path.exists(conf):
274 if os.path.isdir(conf):
275 os.path.walk(conf, parse_config_dir, conf_data)
277 parse_config(bnf, regs, conf)
281 print "Usage: %s <-l> | <-s pattern> | [-n] register [value...]" % prog
283 def decode_value(reg, value, options):
286 except ValueError, e:
287 print "error: invalid value '%s'" % value
290 if i > ((1 << reg.width) - 1):
291 print ("error: value '%s' is too large " + \
292 "for %d-bit register '%s'") % (value, reg.width, reg.id)
295 print reg.decode(i, options['non-zero'])
300 (opts, args) = getopt(sys.argv[1:], "hlns:", \
301 ["help", "list", "non-zero", "search="])
307 regs = parse_all_configs(configs)
308 except ConfigurationError, e:
309 print "Error parsing configuration file %s:\n\t%s" % \
314 print "No configuration available"
318 options['non-zero'] = False
321 if o in ("-h", "--help"):
325 if o in ("-l", "--list"):
329 if o in ("-s", "--search"):
330 list_regs(search_regs(regs, a))
333 if o in ("-n", "--non-zero"):
334 options['non-zero'] = True
341 if not regs.has_key(reg_id):
342 print "No such register '%s'" % reg_id
346 print "decoding as %s" % reg.name
349 value_iter = args.__iter__()
351 value_iter = iter(sys.stdin.readline, '')
354 for value in value_iter:
355 decode_value(reg, value.strip(), options)
356 except KeyboardInterrupt, e:
361 if __name__ == "__main__":