You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
29 lines
853 B
Python
29 lines
853 B
Python
from amaranth import *
|
|
|
|
|
|
__all__ = ["iea", "byte_reversed", "msr_to_srr1"]
|
|
|
|
|
|
def iea(addr, msr_sf):
|
|
"Instruction Effective Address. In 32-bit mode (MSR.SF = 0), bits 0:31 are ignored."
|
|
addr, msr_sf = Value.cast(addr), Value.cast(msr_sf)
|
|
assert len(msr_sf) == 1
|
|
mask = Cat(Repl(1, 32), Repl(msr_sf, 32))
|
|
return addr & mask
|
|
|
|
|
|
def byte_reversed(src, en=0):
|
|
src, en = Value.cast(src), Value.cast(en)
|
|
assert len(src) in {8, 16, 32, 64}
|
|
res = Cat(src.word_select(i, width=8) for i in reversed(range(len(src) // 8)))
|
|
return Mux(en, res, src)
|
|
|
|
|
|
def msr_to_srr1(msr, srr1, start, stop):
|
|
stmts = [
|
|
msr .r_mask[63-stop:64-start].eq(Repl(1, stop-start+1)),
|
|
srr1.w_mask[63-stop:64-start].eq(Repl(1, stop-start+1)),
|
|
srr1.w_data[63-stop:64-start].eq(msr.r_data[63-stop:64-start]),
|
|
]
|
|
return stmts
|