start docs

docs/info.md

@@ -9,12 +9,14 @@ You can also include images in this folder and reference them in the markdown. E
 
 ## How it works
 
-Explain how your project works
+This is a minimal SHA-256 hash core implemented in a single-cycle-round architecture. TODO: expand
+on this
 
 ## How to test
 
-Explain how to use your project
+TODO: write instructions
 
 ## External hardware
 
-List external hardware used in your project (e.g. PMOD, LED display, etc), if any
+No external hardware is needed besides some method of interacting with the bus to transfer commands
+and data.

src/project.v

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024 xenia dragon
+ * SPDX-FileCopyrightText: Copyright (c) 2024 xenia dragon
  * SPDX-License-Identifier: Apache-2.0
  *
  * [usagi holding floppy disk.png] i'll just warn you right now, i don't know how to use a computer

test/test.py

@@ -1,13 +1,96 @@
-# SPDX-FileCopyrightText: © 2024 Tiny Tapeout
+# SPDX-FileCopyrightText: Copyright (c) 2024 xenia dragon
-# SPDX-License-Identifier: MIT
+# SPDX-License-Identifier: Apache-2.0
+
+import hashlib
+import struct
 
 import cocotb
 from cocotb.clock import Clock
 from cocotb.triggers import ClockCycles
 
 
-@cocotb.test()
+IO_RWSEL = 0b0100_0000
-async def test_project(dut):
+IO_CLK = 0b1000_0000
+
+MODE_READ = 1
+MODE_WRITE = 2
+
+class TestMeta:
+    def __init__(self):
+        self.mode = None
+
+
+async def io_write(dut, meta: TestMeta, addr: int, word: int) -> None:
+    assert addr & 0b11 == 0
+
+    if meta.mode != MODE_WRITE:
+        dut.ui_in.value = 0
+        await ClockCycles(dut.clk, 1)
+        meta.mode = MODE_WRITE
+        assert (dut.uo_out.value >> 1) & 1 == 0
+        assert dut.uio_oe.value == 0x00
+        await ClockCycles(dut.clk, 1)
+
+    for i in range(4):
+        # dut._log.info("writing %s=%s",
+        #               f"{addr | i:02x}",
+        #               f"{(word >> (i*8)) & 0xFF:08b}")
+
+        dut.uio_in.value = (word >> (i*8)) & 0xFF
+        dut.ui_in.value = IO_CLK | addr | i
+        await ClockCycles(dut.clk, 1)
+        dut.uio_in.value = (word >> (i*8)) & 0xFF
+        dut.ui_in.value = addr | i
+        await ClockCycles(dut.clk, 1)
+
+
+async def io_read(dut, meta: TestMeta, addr: int) -> int:
+    assert addr & 0b11 == 0
+
+    if meta.mode != MODE_READ:
+        dut.ui_in.value = IO_RWSEL
+        await ClockCycles(dut.clk, 1)
+        meta.mode = MODE_READ
+        assert (dut.uo_out.value >> 1) & 1 == 1
+        assert dut.uio_oe.value == 0xff
+        await ClockCycles(dut.clk, 1)
+
+    word = 0
+    for i in range(4):
+        dut.ui_in.value = IO_CLK | IO_RWSEL | addr | i
+        await ClockCycles(dut.clk, 1)
+        dut.ui_in.value = IO_RWSEL | addr | i
+        await ClockCycles(dut.clk, 1)
+        word |= (dut.uio_out.value & 0xFF) << (i*8)
+
+        # dut._log.info("reading %s=%s",
+        #               f"{addr | i:02x}",
+        #               dut.uio_out.value)
+
+    return word
+
+
+async def io_trigger(dut, meta: TestMeta) -> None:
+    if meta.mode != MODE_WRITE:
+        dut.ui_in.value = 0
+        await ClockCycles(dut.clk, 1)
+        meta.mode = MODE_WRITE
+        assert (dut.uo_out.value >> 1) & 1 == 0
+        assert dut.uio_oe.value == 0x00
+        await ClockCycles(dut.clk, 1)
+
+    dut.uio_in.value = 0
+    dut.ui_in.value = IO_CLK | 63
+    await ClockCycles(dut.clk, 1)
+    dut.uio_in.value = 0
+    dut.ui_in.value = 63
+    await ClockCycles(dut.clk, 1)
+
+
+
+async def test_init(dut):
+    meta = TestMeta()
+
     dut._log.info("Start")
 
     # Set the clock period to 10 us (100 KHz)
@@ -23,18 +106,134 @@ async def test_project(dut):
     await ClockCycles(dut.clk, 10)
     dut.rst_n.value = 1
 
-    dut._log.info("Test project behavior")
+    return meta
 
-    # Set the input values you want to test
-    dut.ui_in.value = 20
-    dut.uio_in.value = 30
 
-    # Wait for one clock cycle to see the output values
+@cocotb.test()
-    await ClockCycles(dut.clk, 1)
+async def test_registers(dut):
+    meta = await test_init(dut)
+    dut._log.info("Test registers")
 
-    # The following assersion is just an example of how to check the output values.
+    for addr in range(0, 40, 4):
-    # Change it to match the actual expected output of your module:
+        dut._log.info("Test register %s", addr)
-    assert dut.uo_out.value == 50
+        for val in [0x1312621, 0, 0xffffffff, 0x13371337, 0x55aa9966]:
+            await io_write(dut, meta, addr, val)
+            rval = await io_read(dut, meta, addr)
+            assert val == rval
 
-    # Keep testing the module by changing the input values, waiting for
+
-    # one or more clock cycles, and asserting the expected output values.
+K = [0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+     0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+     0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+     0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+     0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+     0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+     0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+     0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+     0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+     0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+     0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+     0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+     0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+     0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+     0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+     0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2]
+
+H = [0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
+     0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19]
+
+def _rotr(x, y):
+    return ((x >> y) | (x << (32 - y))) & 0xFFFFFFFF
+
+def _maj(x, y, z):
+    return (x & y) ^ (x & z) ^ (y & z)
+
+def _ch(x, y, z):
+    return (x & y) ^ ((~x) & z)
+
+
+@cocotb.test()
+async def test_sha_round(dut):
+    meta = await test_init(dut)
+    dut._log.info("Test SHA-2 compression cycle")
+    for w in [0x1312621, 0, 0xffffffff, 0x13371337, 0x55aa9966]:
+        for i in range(8):
+            await io_write(dut, meta, i*4, H[i])
+        await io_write(dut, meta, 32, w)
+        await io_write(dut, meta, 36, K[0])
+
+        await io_trigger(dut, meta)
+
+        a, b, c, d, e, f, g, h = H
+        s0 = _rotr(a, 2) ^ _rotr(a, 13) ^ _rotr(a, 22)
+        t2 = s0 + _maj(a, b, c)
+        s1 = _rotr(e, 6) ^ _rotr(e, 11) ^ _rotr(e, 25)
+        t1 = h + s1 + _ch(e, f, g) + K[0] + w
+
+        h = g
+        g = f
+        f = e
+        e = (d + t1) & 0xFFFFFFFF
+        d = c
+        c = b
+        b = a
+        a = (t1 + t2) & 0xFFFFFFFF
+
+        expected = [a, b, c, d, e, f, g, h]
+
+        for i in range(8):
+            actual = await io_read(dut, meta, i*4)
+            assert actual == expected[i]
+
+
+async def test_one_sha_full(dut, meta, message: bytes) -> None:
+    reference_hash = hashlib.sha256(message).digest()
+
+    mdi = len(message) & 0x3F
+    length = struct.pack('!Q', len(message) << 3)
+
+    if mdi < 56:
+        padlen = 55 - mdi
+    else:
+        padlen = 119 - mdi
+
+    message = message + b'\x80' + (b'\x00' * padlen) + length
+
+    assert len(message) % 64 == 0
+
+    h = list(H)
+
+    for chunk_idx in range(0, len(message), 64):
+        chunk = message[chunk_idx:chunk_idx+64]
+
+        for i in range(8):
+            await io_write(dut, meta, i*4, h[i])
+
+        w = [0] * 64
+        w[0:16] = struct.unpack('!16L', chunk)
+        for i in range(16, 64):
+            s0 = _rotr(w[i-15], 7) ^ _rotr(w[i-15], 18) ^ (w[i-15] >> 3)
+            s1 = _rotr(w[i-2], 17) ^ _rotr(w[i-2], 19) ^ (w[i-2] >> 10)
+            w[i] = (w[i-16] + s0 + w[i-7] + s1) & 0xFFFFFFFF
+
+        for i in range(64):
+            await io_write(dut, meta, 32, w[i])
+            await io_write(dut, meta, 36, K[i])
+
+            await io_trigger(dut, meta)
+
+        for i in range(8):
+            h[i] = (h[i] + (await io_read(dut, meta, i*4))) & 0xFFFFFFFF
+
+    result = struct.pack("!IIIIIIII", *h)
+    assert result == reference_hash
+
+@cocotb.test()
+async def test_sha_full(dut):
+    meta = await test_init(dut)
+    dut._log.info("Test SHA-2 full hash")
+
+    await test_one_sha_full(dut, meta, b"")
+    await test_one_sha_full(dut, meta, b"message digest")
+    await test_one_sha_full(dut, meta, b"trans rights")
+    await test_one_sha_full(dut, meta, b"abababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababababab")