skywalker-1/tools/a8_autoclear_test.py

#!/usr/bin/env python3
"""Test whether BCM4500 register A8 auto-clears after write commands.

If A8 auto-clears to 0x00 (or 0x02) after writing 0x03, then
bcm_poll_ready() would always return TRUE, masking the fact that
the DSP isn't processing commands.

Uses enhanced 0xB6 diagnostic:
  wValue = page, wIndex = A8 command (0 = default READ)
  Returns 8 bytes:
    [0] write_A6_ok
    [1] A6 readback
    [2] write_A8_ok
    [3] A8 IMMEDIATE readback (no delay)
    [4] A8 after 2ms delay
    [5] A7 data result
    [6] A6 final state
    [7] echo: command sent
"""
import sys
import time
sys.path.insert(0, 'tools')
from skywalker_lib import SkyWalker1

CMD_I2C_DIAG = 0xB6
CMD_I2C_RAW_READ = 0xB5
BCM4500_ADDR = 0x08

sw = SkyWalker1()
sw.open()
print('=== A8 Auto-Clear Test ===')
print(f'Firmware: {sw.get_fw_version()}')

# Boot with full sequence
print('\n--- Booting BCM4500 (full boot) ---')
result = sw._vendor_in(0x89, value=1, index=0, length=3)
cfg, stage = result[0], result[1]
print(f'  Config: 0x{cfg:02X}, Stage: 0x{stage:02X}')

# Read A8 default state before any commands
print('\n--- A8 default state (after boot, before diagnostic) ---')
a8_default = sw._vendor_in(CMD_I2C_RAW_READ, value=BCM4500_ADDR,
                            index=0xA8, length=1)
print(f'  A8 default: 0x{a8_default[0]:02X} (bit0={a8_default[0] & 0x01})')

# Test 1: READ command (0x01) — this was the previous behavior
print('\n=== Test 1: A8 with READ command (0x01) ===')
diag1 = sw._vendor_in(CMD_I2C_DIAG, value=0x06, index=0x01, length=8)
print(f'  A6 write ok:       {diag1[0]}')
print(f'  A6 readback:       0x{diag1[1]:02X}')
print(f'  A8 write ok:       {diag1[2]}')
print(f'  A8 IMMEDIATE:      0x{diag1[3]:02X} (bit0={diag1[3] & 0x01})')
print(f'  A8 after 2ms:      0x{diag1[4]:02X} (bit0={diag1[4] & 0x01})')
print(f'  A7 data:           0x{diag1[5]:02X}')
print(f'  A6 final:          0x{diag1[6]:02X}')
print(f'  Command sent:      0x{diag1[7]:02X}')

# Reset A8 back to default by reading
time.sleep(0.01)

# Test 2: WRITE command (0x03) — the one used by init blocks
print('\n=== Test 2: A8 with WRITE command (0x03) ===')
diag2 = sw._vendor_in(CMD_I2C_DIAG, value=0x06, index=0x03, length=8)
print(f'  A6 write ok:       {diag2[0]}')
print(f'  A6 readback:       0x{diag2[1]:02X}')
print(f'  A8 write ok:       {diag2[2]}')
print(f'  A8 IMMEDIATE:      0x{diag2[3]:02X} (bit0={diag2[3] & 0x01})')
print(f'  A8 after 2ms:      0x{diag2[4]:02X} (bit0={diag2[4] & 0x01})')
print(f'  A7 data:           0x{diag2[5]:02X}')
print(f'  A6 final:          0x{diag2[6]:02X}')
print(f'  Command sent:      0x{diag2[7]:02X}')

# Test 3: Try other A8 values
print('\n=== Test 3: Various A8 values ===')
for cmd in [0x00, 0x02, 0x04, 0xFF]:
    time.sleep(0.01)
    diag = sw._vendor_in(CMD_I2C_DIAG, value=0x00, index=cmd, length=8)
    print(f'  CMD=0x{cmd:02X}: A8_imm=0x{diag[3]:02X} A8_2ms=0x{diag[4]:02X} '
          f'A7=0x{diag[5]:02X}')

# Analysis
print('\n=== Analysis ===')
if diag2[3] != 0x03 or diag2[4] != 0x03:
    print(f'  !! A8 AUTO-CLEARS after WRITE command!')
    print(f'     Wrote 0x03, immediate={diag2[3]:02X}, after_2ms={diag2[4]:02X}')
    if (diag2[3] & 0x01) == 0 or (diag2[4] & 0x01) == 0:
        print(f'     bcm_poll_ready() sees bit0=0 → always returns TRUE')
        print(f'     Init blocks appear to succeed but DSP never processes them!')
else:
    print(f'  A8 retains WRITE command (0x03). No auto-clear.')
    if (diag1[3] == 0x01) and (diag2[3] == 0x03):
        print(f'  Both READ and WRITE commands stick. DSP is genuinely not processing.')

sw.close()
print('\n=== Done ===')