X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fsoc%2Fdecoder%2Fisa%2Fcaller.py;h=39d99d5e4fbe4d6fec12999e48e0514e6835bdfe;hb=5d496a6b50ec3b9e00586e777651c60a1921688d;hp=5b1c4c997148f30f25cf7af60151cf870c04bcd7;hpb=b5e4e847c2841189386da3509949d9206de92f8b;p=soc.git

diff --git a/src/soc/decoder/isa/caller.py b/src/soc/decoder/isa/caller.py
index 5b1c4c99..39d99d5e 100644
--- a/src/soc/decoder/isa/caller.py
+++ b/src/soc/decoder/isa/caller.py
@@ -1,6 +1,7 @@
 from functools import wraps
 from soc.decoder.orderedset import OrderedSet
 from soc.decoder.selectable_int import SelectableInt, selectconcat
+import math
 
 def create_args(reglist, extra=None):
     args = OrderedSet()
@@ -13,23 +14,59 @@ def create_args(reglist, extra=None):
 
 class Mem:
 
-    def __init__(self):
-        self.mem = []
-        for i in range(128):
-            self.mem.append(i)
+    def __init__(self, bytes_per_word=8):
+        self.mem = {}
+        self.bytes_per_word = bytes_per_word
+        self.word_log2 = math.ceil(math.log2(bytes_per_word))
+
+    def _get_shifter_mask(self, width, remainder):
+        shifter = ((self.bytes_per_word - width) - remainder) * \
+            8  # bits per byte
+        mask = (1 << (width * 8)) - 1
+        return shifter, mask
+
+    # TODO: Implement ld/st of lesser width
+    def ld(self, address, width=8):
+        remainder = address & (self.bytes_per_word - 1)
+        address = address >> self.word_log2
+        assert remainder & (width - 1) == 0, "Unaligned access unsupported!"
+        if address in self.mem:
+            val = self.mem[address]
+        else:
+            val = 0
+
+        if width != self.bytes_per_word:
+            shifter, mask = self._get_shifter_mask(width, remainder)
+            val = val & (mask << shifter)
+            val >>= shifter
+        print("Read {:x} from addr {:x}".format(val, address))
+        return val
+
+    def st(self, address, value, width=8):
+        remainder = address & (self.bytes_per_word - 1)
+        address = address >> self.word_log2
+        assert remainder & (width - 1) == 0, "Unaligned access unsupported!"
+        print("Writing {:x} to addr {:x}".format(value, address))
+        if width != self.bytes_per_word:
+            if address in self.mem:
+                val = self.mem[address]
+            else:
+                val = 0
+            shifter, mask = self._get_shifter_mask(width, remainder)
+            val &= ~(mask << shifter)
+            val |= value << shifter
+            self.mem[address] = val
+        else:
+            self.mem[address] = value
 
     def __call__(self, addr, sz):
-        res = []
-        for s in range(sz): # TODO: big/little-end
-            res.append(SelectableInt(self.mem[addr.value + s], 8))
-        print ("memread", addr, sz, res)
-        return selectconcat(*res)
+        val = self.ld(addr.value, sz)
+        print ("memread", addr, sz, val)
+        return SelectableInt(val, sz*8)
 
     def memassign(self, addr, sz, val):
         print ("memassign", addr, sz, val)
-        for s in range(sz):
-            byte = (val.value) >> (s*8) & 0xff # TODO: big/little-end
-            self.mem[addr.value + s] = byte
+        self.st(addr.value, val.value, sz)
 
 
 class GPR(dict):
@@ -86,33 +123,48 @@ class ISACaller:
     def memassign(self, ea, sz, val):
         self.mem.memassign(ea, sz, val)
 
-    def prep_namespace(self):
-        si = yield self.decoder.SI
-        self.namespace['SI'] = SelectableInt(si, bits=16)
+    def prep_namespace(self, formname, op_fields):
+        # TODO: get field names from form in decoder*1* (not decoder2)
+        # decoder2 is hand-created, and decoder1.sigform is auto-generated
+        # from spec
+        # then "yield" fields only from op_fields rather than hard-coded
+        # list, here.
+        fields = self.decoder.sigforms[formname]
+        for name in fields._fields:
+            if name not in ["RA", "RB", "RT"]:
+                sig = getattr(fields, name)
+                val = yield sig
+                self.namespace[name] = SelectableInt(val, sig.width)
 
     def call(self, name):
-        yield from self.prep_namespace()
+        # TODO, asmregs is from the spec, e.g. add RT,RA,RB
+        # see http://bugs.libre-riscv.org/show_bug.cgi?id=282
+        fn, read_regs, uninit_regs, write_regs, op_fields, form, asmregs \
+            = self.instrs[name]
+        yield from self.prep_namespace(form, op_fields)
 
-        function, read_regs, uninit_regs, write_regs = self.instrs[name]
         input_names = create_args(read_regs | uninit_regs)
         print(input_names)
 
         inputs = []
         for name in input_names:
             regnum = yield getattr(self.decoder, name)
+            regname = "_" + name
+            self.namespace[regname] = regnum
             print('reading reg %d' % regnum)
             inputs.append(self.gpr(regnum))
         print(inputs)
-        results = function(self, *inputs)
+        results = fn(self, *inputs)
         print(results)
 
-        output_names = create_args(write_regs)
-        for name, output in zip(output_names, results):
-            regnum = yield getattr(self.decoder, name)
-            print('writing reg %d' % regnum)
-            if isinstance(output, int):
-                output = SelectableInt(output, 64)
-            self.gpr[regnum] = output
+        if write_regs:
+            output_names = create_args(write_regs)
+            for name, output in zip(output_names, results):
+                regnum = yield getattr(self.decoder, name)
+                print('writing reg %d' % regnum)
+                if output.bits > 64:
+                    output = SelectableInt(output.value, 64)
+                self.gpr[regnum] = output
 
 
 def inject():