cvw/tests/testgen/privileged/testgen-TVEC.py

474 lines
14 KiB
Python
Executable File

#!/usr/bin/env python3
##################################
# testgen-TVEC.py (new)
#
# dottolia@hmc.edu 1 Mar 2021
#
# Generate directed and random test vectors for RISC-V Design Validation.
#
#
##################################
# DOCUMENTATION:
#
# The most up-to-date comments explaining what everything
# does and the layout of the privileged tests
# can be found in testgen-TVAL.py. This and
# other files do not have as many comments
#
###################################
##################################
# libraries
##################################
from datetime import datetime
from random import randint
from random import seed
from random import getrandbits
##################################
# setup
##################################
areVectoredTrapsSupported = True
##################################
# functions
##################################
#For instruction-fetch access or page-fault exceptions on systems with variable-length instructions, mtval will contain the virtual address of the portion of the instruction that caused the fault while mepc will point to the beginning of the instruction.
def randRegs():
reg1 = randint(1,20)
reg2 = randint(1,20)
reg3 = randint(1,20)
if (reg1 == 6 or reg2 == 6 or reg3 == 6 or reg1 == reg2):
return randRegs()
else:
return str(reg1), str(reg2), str(reg3)
def writeVectors(storecmd, returningInstruction):
global testnum
# Illegal Instruction
# writeTest(storecmd, f, r, f"""
# .fill 1, 4, 0
# """, False, 0)
# # Breakpoint
# if returningInstruction != "ebreak":
# writeTest(storecmd, f, r, f"""
# ebreak
# """, False, 0)
# # Load Address Misaligned
# writeTest(storecmd, f, r, f"""
# lw x0, 11(x0)
# """, False, 0)
# # Load Access fault: False, 5
# # Store/AMO address misaligned
# writeTest(storecmd, f, r, f"""
# sw x0, 11(x0)
# """, False, 0)
# # Environment call from u-mode: only for when only M and U mode enabled?
# # writeTest(storecmd, f, r, f"""
# # ecall
# # """, False, 8, "u")
if returningInstruction != "ecall":
writeTest(storecmd, f, r, f"""
ecall
""", False, 0)
if fromMode == "m" and testMode == "m":
expectedCode = 7 if fromMode == "m" else 5
clintAddr = "0x2004000"
writeTest(storecmd, f, r, f"""
li x1, 0x8
csrrs x0, {fromMode}status, x1
la x18, {clintAddr}
# lw x11, 0(x18)
# li x1, 0x3fffffffffffffff
# {storecmd} x1, 0(x18)
li x1, 0x80
csrrs x0, {fromMode}ie, x1
{storecmd} x0, 0(x18)
""", True, expectedCode, f"""
li x1, 0x80
csrrc x0, {fromMode}ie, x1
li x1, 0x8
csrrc x0, {fromMode}status, x1
la x18, {clintAddr}
{storecmd} x0, 0(x18)
""")
# Instruction page fault: 12
# Load page fault: 13
# Store/AMO page fault: 15
def writeTest(storecmd, f, r, test, interrupt, code, resetHander = ""):
global testnum, storeAddressOffset, xlen
expected = code
# Boilerplate
#
# x28 is the address that our trap handler will jump to before returning.
# This is where we can do our actual tests. After we're done computing and storing
# what we want, we jump to x27, which continues with the trap handling code (look at the _j_x_trap_... labels)
#
lines = f"""
la x28, _jtest{testnum}
j _jdo{testnum}
_jtest{testnum}:
nop
{resetHander}
jr x27
_jdo{testnum}:
li x25, 0xDEADBEA7
{test}
"""
if not areVectoredTrapsSupported or not vectoredInterrupts:
expected = 0
writeGeneralTest(storecmd, f, r, lines, expected)
def writeGeneralTest(storecmd, f, r, test, expected):
global testnum, storeAddressOffset, xlen
lines = f"""
{test}
{storecmd} x25, {testnum * wordsize}(x6)
"""
f.write(lines)
if (xlen == 32):
line = formatrefstr.format(expected)+"\n"
else:
line = formatrefstr.format(expected % 2**32)+"\n" + formatrefstr.format(expected >> 32) + "\n"
r.write(line)
testnum = testnum+1
##################################
# main body
##################################
author = "dottolia@hmc.edu"
xlens = [32, 64]
testCount = 4;
# setup
# Change this seed to a different constant value for every test
seed(0xC363DAEB9193AB45) # make tests reproducible
# generate files for each test
for xlen in xlens:
formatstrlen = str(int(xlen/4))
formatstr = "0x{:0" + formatstrlen + "x}" # format as xlen-bit hexadecimal number
formatrefstr = "{:08x}" # format as xlen-bit hexadecimal number with no leading 0x
if (xlen == 32):
storecmd = "sw"
wordsize = 4
else:
storecmd = "sd"
wordsize = 8
# testMode can be m, s, and u. User mode traps are deprecated, so this should likely just be ["m", "s"]
for testMode in ["m", "s"]:
imperaspath = "../../../imperas-riscv-tests/riscv-test-suite/rv" + str(xlen) + "p/"
basename = "WALLY-" + testMode.upper() + "TVEC"
fname = imperaspath + "src/" + basename + ".S"
refname = imperaspath + "references/" + basename + ".reference_output"
testnum = 0
storeAddressOffset = 0
# print custom header part
f = open(fname, "w")
r = open(refname, "w")
line = "///////////////////////////////////////////\n"
f.write(line)
lines="// "+fname+ "\n// " + author + "\n"
f.write(lines)
line ="// Created " + str(datetime.now())
f.write(line)
# insert generic header
h = open("../testgen_header.S", "r")
for line in h:
f.write(line)
# Ensure MODE of *tvec (last 2 bits) is either 00 or 01
f.write(f"""
csrr x19, {testMode}tvec
""")
for i in range(0, 16):
i = i;
trySet = i | 0b10;
expected = trySet & 0xFFFF_FFFFD;
writeGeneralTest(storecmd, f, r, f"""
li x1, {trySet}
csrw {testMode}tvec, x1
csrr x25, {testMode}tvec
""", expected)
f.write(f"""
csrw {testMode}tvec, x19
""")
# We need to leave at least one bit in medeleg unset so that we have a way to get
# back to machine mode when the tests are complete (otherwise we'll only ever be able
# to get up to supervisor mode).
#
# So, we define a returning instruction which will be used to cause the exception that
# brings us into machine mode. The bit for this returning instruction is NOT set in
# medeleg. However, this also means that we can't test that instruction. So, we have
# two different returning instructions.
#
# Current code is written to only support ebreak and ecall.
#
# For testgen-TVAL, we don't need to test ebreak, so we can use that as the sole
# returning instruction. For others, like testgen-CAUSE, we'll need to put
# both ebreak and ecall here.
for returningInstruction in ["ebreak"]:
for vectoredInterrupts in [True, False]:
# All registers used:
# x30: set to 1 if we should return to & stay in machine mode after trap, 0 otherwise
# ...
# x28: address trap handler should jump to for the test
# x27: address the test should return to after the test
# ...
# x25: value to write to memory
# ...
# x20: intermediate value in trap handler. Don't overwrite this!
# x19: mtvec old value
# x18: medeleg old value
# x17: sedeleg old value (currently unused — user mode traps deprecated)
# x16: mideleg old value
# ...
# x10 - x14 can be freely written
# ...
# x7: copy of x6. Increment this instead of using an offset on x6.
# this allows us to create more than 2048/wordlen tests.
# This is the address we write results to
# x6: Starting address we should write expected results to
# ...
# x1 - x5 can be freely written
# Set up x7 and store old value of mtvec
lines = f"""
# add x7, x6, x0
csrr x19, mtvec
"""
# Not used — user mode traps are deprecated
if testMode == "u":
lines += f"""
csrr x17, sedeleg
li x9, {"0b1100000000" if testMode == "u" else "0b0000000000"}
csrs sedeleg, x9
"""
# Code that will jump to the test (x28 is set in writeTest above)
testJumpCode = f"""
auipc x27, 0
addi x27, x27, 12
jr x28
"""
beforeCode = {"m": "", "s": ""}
for pm in ["m", "s"]:
for i in range(0, 16):
beforeCode[pm] = beforeCode[pm] + f"""
nop
nop
li x25, {i}
j _j_{pm}_trap_end_{returningInstruction}_{vectoredInterrupts}
"""
# Code for handling traps in different modes
# Some comments are inside of the below strings (prefixed with a #, as you might expected)
enableVectored = "addi x1, x1, 1" if vectoredInterrupts else ""
lines += f"""
# Reset x30 to 0 so we can run the tests. We'll set this to 1 when tests are completed so we stay in machine mode
li x30, 0
# Set up
la x1, _j_m_trap_{returningInstruction}_{vectoredInterrupts}
{enableVectored} # enable/don't enable vectored interrupts
csrw mtvec, x1
la x1, _j_s_trap_{returningInstruction}_{vectoredInterrupts}
{enableVectored} # enable/don't enable vectored interrupts
csrw stvec, x1
la x1, _j_u_trap_{returningInstruction}_{vectoredInterrupts}
{enableVectored} # enable/don't enable vectored interrupts
# csrw utvec, x1 # user mode traps are not supported
# Start the tests!
j _j_t_begin_{returningInstruction}_{vectoredInterrupts}
# Machine mode traps
_j_m_trap_{returningInstruction}_{vectoredInterrupts}:
{beforeCode['m']}
_j_m_trap_end_{returningInstruction}_{vectoredInterrupts}:
{testJumpCode}
csrrs x20, mepc, x0
addi x20, x20, 4
csrrw x0, mepc, x20
bnez x30, _j_all_end_{returningInstruction}_{vectoredInterrupts}
mret
# Supervisor mode traps
_j_s_trap_{returningInstruction}_{vectoredInterrupts}:
{beforeCode['s']}
_j_s_trap_end_{returningInstruction}_{vectoredInterrupts}:
{testJumpCode}
csrrs x20, sepc, x0
addi x20, x20, 4
csrrw x0, sepc, x20
bnez x30, _j_goto_machine_mode_{returningInstruction}_{vectoredInterrupts}
sret
# Unused: user mode traps are no longer supported
_j_u_trap_{returningInstruction}_{vectoredInterrupts}:
{testJumpCode if testMode == "u" else "li x25, 0xBAD00000"}
csrrs x20, uepc, x0
addi x20, x20, 4
csrrw x0, uepc, x20
bnez x30, _j_goto_supervisor_mode_{returningInstruction}_{vectoredInterrupts}
uret
# Currently unused. Just jumps to _j_goto_machine_mode. If you actually
# want to implement this, you'll likely need to reset sedeleg here
# and then cause an exception with {returningInstruction} (based on my intuition. Try that first, but I could be missing something / just wrong)
_j_goto_supervisor_mode_{returningInstruction}_{vectoredInterrupts}:
j _j_goto_machine_mode_{returningInstruction}_{vectoredInterrupts}
_j_goto_machine_mode_{returningInstruction}_{vectoredInterrupts}:
li x30, 1 # This will cause us to branch to _j_all_end_{returningInstruction}_{vectoredInterrupts} in the machine trap handler, which we'll get into by invoking...
{returningInstruction} # ... this instruction!
# Run the actual tests!
_j_t_begin_{returningInstruction}_{vectoredInterrupts}:
"""
fromModeOptions = ["m", "s", "u"] if testMode == "m" else (["s", "u"] if testMode == "s" else ["u"])
# We don't want to delegate our returning instruction. Otherwise, we'll have no way of getting
# back to machine mode at the end! (and we need to be in machine mode to complete the tests)
medelegMask = "0b1111111111110111" if returningInstruction == "ebreak" else "0b1111000011111111"
# Set medeleg and mideleg
lines += f"""
csrr x18, medeleg
li x9, {medelegMask if testMode == "s" or testMode == "u" else "0"}
csrw medeleg, x9
csrr x16, mideleg
li x9, {"0xffffffff" if testMode == "s" or testMode == "u" else "0"}
csrw mideleg, x9
"""
f.write(lines)
for fromMode in fromModeOptions:
lines = ""
# Code to bring us down to supervisor mode
if fromMode == "s" or fromMode == "u":
lines += f"""
li x1, 0b110000000000
csrrc x31, mstatus, x1
li x1, 0b0100000000000
csrrs x31, mstatus, x1
auipc x1, 0
addi x1, x1, 16 # x1 is now right after the mret instruction
csrw mepc, x1
mret
# We're now in supervisor mode...
"""
# Code to bring us down to user mode
if fromMode == "u":
lines += f"""
li x1, 0b110000000000
csrrc x31, sstatus, x1
auipc x1, 0
addi x1, x1, 16 # x1 is now right after the sret instruction
csrw sepc, x1
sret
# We're now in user mode...
"""
f.write(lines)
for i in range(0,testCount):
writeVectors(storecmd, returningInstruction)
# Very end of test. Bring us back up to machine mode
# We set x30 to 1, which will cause us to branch to _j_all_end in the
# machine mode trap handler, before executing the mret instruction. This will
# make us stay in machine mode.
#
# If we're currently in user mode, this will first bump us up to the supervisor mode
# trap handler, which will call returningInstruction again before it's sret instruction,
# bumping us up to machine mode
#
# Get into the trap handler by running returningInstruction (either an ecall or ebreak)
f.write(f"""
li x30, 1
li gp, 0
{returningInstruction}
_j_all_end_{returningInstruction}_{vectoredInterrupts}:
# Reset trap handling csrs to old values
csrw mtvec, x19
csrw medeleg, x18
csrw mideleg, x16
""")
# print footer
h = open("../testgen_footer.S", "r")
for line in h:
f.write(line)
# Finish
lines = ".fill " + str(testnum) + ", " + str(wordsize) + ", -1\n"
lines = lines + "\nRV_COMPLIANCE_DATA_END\n"
f.write(lines)
f.close()
r.close()