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|
#
# Copyright 2018 Ettus Research, a National Instruments Company
#
# SPDX-License-Identifier: GPL-3.0-or-later
#
"""
Helper class to initialize a Rhodium daughterboard
"""
from __future__ import print_function
import time
from usrp_mpm.sys_utils.uio import UIO
from usrp_mpm.dboard_manager.lmk_rh import LMK04828Rh
from usrp_mpm.dboard_manager.rh_periphs import DboardClockControl
from usrp_mpm.cores import ClockSynchronizer
from usrp_mpm.cores import nijesdcore
from usrp_mpm.cores.eyescan import EyeScanTool
from usrp_mpm.dboard_manager.gain_rh import GainTableRh
class RhodiumInitManager(object):
"""
Helper class: Holds all the logic to initialize an N320/N321 (Rhodium)
daughterboard.
"""
# After manually probing the PLL1's reference and feedback signal from the LMK
# using multiple phase dac values close to its midpoint (2^11 = 2048), it was
# discovered that the PLL1's tightest phase lock is at 2024.
INIT_PHASE_DAC_WORD = 32768 # TODO: update this number for Rev. B
PHASE_DAC_SPI_ADDR = 0x3
# External PPS pipeline delay from the PPS captured at the FPGA to TDC input,
# in reference clock ticks
EXT_PPS_DELAY = 5
# Variable PPS delay before the RP/SP pulsers begin. Fixed value for the N3xx devices.
N3XX_INT_PPS_DELAY = 4
# JESD core default configuration.
# TODO: define the actual values for rx_sysref_delay and tx_sysref_delay.
JESD_DEFAULT_ARGS = {"lmfc_divider" : 12,
"rx_sysref_delay": 8,
"tx_sysref_delay": 11,
"tx_driver_swing": 0b1101,
"tx_precursor" : 0b00100,
"tx_postcursor" : 0b00100}
def __init__(self, rh_class, spi_ifaces):
self.rh_class = rh_class
self._spi_ifaces = spi_ifaces
self.adc = rh_class.adc
self.dac = rh_class.dac
self.slot_idx = rh_class.slot_idx
self.log = rh_class.log.getChild('init')
def _init_lmk(self, lmk_spi, ref_clk_freq, sampling_clock_rate,
pdac_spi, init_phase_dac_word, phase_dac_spi_addr):
"""
Sets the phase DAC to initial value, and then brings up the LMK
according to the selected ref clock frequency.
Will throw if something fails.
"""
self.log.trace("Initializing Phase DAC to d{}.".format(
init_phase_dac_word
))
pdac_spi.poke16(phase_dac_spi_addr, init_phase_dac_word)
return LMK04828Rh(self.slot_idx, lmk_spi, ref_clk_freq, sampling_clock_rate, self.log)
# TODO: update phase shift value after testing phase DAC flatness with shields (Rev. B)
def _sync_db_clock(self, dboard_ctrl_regs, ref_clk_freq, master_clock_rate, args):
" Synchronizes the DB clock to the common reference "
reg_offset = 0x200
ext_pps_delay = self.EXT_PPS_DELAY
if args.get('time_source', self.rh_class.default_time_source) == 'sfp0':
reg_offset = 0x400
ref_clk_freq = 62.5e6
ext_pps_delay = 1 # only 1 flop between the WR core output and the TDC input
synchronizer = ClockSynchronizer(
dboard_ctrl_regs,
self.rh_class.lmk,
self._spi_ifaces['phase_dac'],
reg_offset,
master_clock_rate,
ref_clk_freq,
1.1E-12, # fine phase shift. TODO don't hardcode. This should live in the EEPROM
self.INIT_PHASE_DAC_WORD,
self.PHASE_DAC_SPI_ADDR,
ext_pps_delay,
self.N3XX_INT_PPS_DELAY,
self.slot_idx)
# The radio clock traces on the motherboard are 69 ps longer for Daughterboard B
# than Daughterboard A. We want both of these clocks to align at the converters
# on each board, so adjust the target value for DB B. This is an N3xx series
# peculiarity and will not apply to other motherboards.
trace_delay_offset = {0: 0.0e-0,
1: 69.0e-12}[self.slot_idx]
offset_error = abs(synchronizer.run(
num_meas=[512, 128],
target_offset=trace_delay_offset))
if offset_error > 100e-12:
self.log.error("Clock synchronizer measured an offset of {:.1f} ps!".format(
offset_error*1e12
))
self.log.warning("RuntimeError is not being thrown for Rhodium Rev. A")
# raise RuntimeError("Clock synchronizer measured an offset of {:.1f} ps!".format(
# offset_error*1e12
# ))
else:
self.log.debug("Residual synchronization error: {:.1f} ps.".format(
offset_error*1e12
))
synchronizer = None
self.log.debug("Sample Clock Synchronization Complete!")
def set_jesd_rate(self, jesdcore, new_rate, current_jesd_rate, force=False):
"""
Make the QPLL and GTX changes required to change the JESD204B core rate.
"""
# The core is directly compiled for 500 MHz sample rate, which
# corresponds to a lane rate of 5.0 Gbps. The same QPLL and GTX settings apply
# for the 491.52 MHz sample rate.
#
# The lower non-LTE rate, 400 MHz, requires changes to the default configuration
# of the MGT components. This function performs the required changes in the
# following order (as recommended by UG476).
#
# 1) Modify any QPLL settings.
# 2) Perform the QPLL reset routine by pulsing reset then waiting for lock.
# 3) Modify any GTX settings.
# 4) Perform the GTX reset routine by pulsing reset and waiting for reset done.
assert new_rate in (4000e6, 4915.2e6, 5000e6)
# On first run, we have no idea how the FPGA is configured... so let's force an
# update to our rate.
force = force or (current_jesd_rate is None)
skip_drp = False
if not force:
# Current New Skip?
skip_drp = {4000.0e6 : {4000.0e6: True , 4915.2e6: False, 5000.0e6: False},
4915.2e6 : {4000.0e6: False, 4915.2e6: True , 5000.0e6: True },
5000.0e6 : {4000.0e6: False, 4915.2e6: True , 5000.0e6: True }}[current_jesd_rate][new_rate]
if skip_drp:
self.log.trace("Current lane rate is compatible with the new rate. Skipping "
"reconfiguration.")
# These are the only registers in the QPLL and GTX that change based on the
# selected line rate. The MGT wizard IP was generated for each of the rates and
# reference clock frequencies and then diffed to create this table.
QPLL_CFG = {4000.0e6: 0x6801C1, 4915.2e6: 0x680181, 5000.0e6: 0x0680181}[new_rate]
MGT_RX_CLK25_DIV = {4000.0e6: 8, 4915.2e6: 10, 5000.0e6: 10}[new_rate]
MGT_TX_CLK25_DIV = {4000.0e6: 8, 4915.2e6: 10, 5000.0e6: 10}[new_rate]
# 1-2) Do the QPLL first
if not skip_drp:
self.log.trace("Changing QPLL settings to support {} Gbps".format(new_rate/1e9))
jesdcore.set_drp_target('qpll', 0)
# QPLL_CONFIG is spread across two regs: 0x32 (dedicated) and 0x33 (shared)
reg_x32 = QPLL_CFG & 0xFFFF # [16:0] -> [16:0]
reg_x33 = jesdcore.drp_access(rd=True, addr=0x33)
reg_x33 = (reg_x33 & 0xF800) | ((QPLL_CFG >> 16) & 0x7FF) # [26:16] -> [11:0]
jesdcore.drp_access(rd=False, addr=0x32, wr_data=reg_x32)
jesdcore.drp_access(rd=False, addr=0x33, wr_data=reg_x33)
# Run the QPLL reset sequence and prep the MGTs for modification.
jesdcore.init()
# 3-4) And the 4 MGTs second
if not skip_drp:
self.log.trace("Changing MGT settings to support {} Gbps"
.format(new_rate/1e9))
for lane in range(4):
jesdcore.set_drp_target('mgt', lane)
# MGT_RX_CLK25_DIV is embedded with others in 0x11. The
# encoding for the DRP register value is one less than the
# desired value.
reg_x11 = jesdcore.drp_access(rd=True, addr=0x11)
reg_x11 = (reg_x11 & 0xF83F) | \
((MGT_RX_CLK25_DIV-1 & 0x1F) << 6) # [10:6]
jesdcore.drp_access(rd=False, addr=0x11, wr_data=reg_x11)
# MGT_TX_CLK25_DIV is embedded with others in 0x6A. The
# encoding for the DRP register value is one less than the
# desired value.
reg_x6a = jesdcore.drp_access(rd=True, addr=0x6A)
reg_x6a = (reg_x6a & 0xFFE0) | (MGT_TX_CLK25_DIV-1 & 0x1F) # [4:0]
jesdcore.drp_access(rd=False, addr=0x6A, wr_data=reg_x6a)
self.log.trace("GTX settings changed to support {} Gbps"
.format(new_rate/1e9))
jesdcore.disable_drp_target()
self.log.trace("JESD204b Lane Rate set to {} Gbps!"
.format(new_rate/1e9))
return new_rate
def init_jesd(self, jesdcore, sampling_clock_rate):
"""
Bringup the JESD links between the ADC, DAC, and the FPGA.
All clocks must be set up and stable before starting this routine.
"""
jesdcore.check_core()
# JESD Lane Rate only depends on the sampling_clock_rate selection, since all
# other link parameters (LMFS,N) remain constant.
L = 4
M = 2
F = 1
S = 1
N = 16
new_rate = sampling_clock_rate * M * N * (10.0/8) / L / S
self.log.trace("Calculated JESD204B lane rate is {} Gbps".format(new_rate/1e9))
self.rh_class.current_jesd_rate = \
self.set_jesd_rate(jesdcore, new_rate, self.rh_class.current_jesd_rate)
self.log.trace("Setting up JESD204B TX blocks.")
jesdcore.init_framer() # Initialize FPGA's framer.
self.adc.init_framer() # Initialize ADC's framer.
self.log.trace("Enabling SYSREF capture blocks.")
self.dac.enable_sysref_capture(True) # Enable DAC's SYSREF capture.
self.adc.enable_sysref_capture(True) # Enable ADC's SYSREF capture.
jesdcore.enable_lmfc(True) # Enable FPGA's SYSREF capture.
self.log.trace("Setting up JESD204B DAC RX block.")
self.dac.init_deframer() # Initialize DAC's deframer.
self.log.trace("Sending SYSREF to all devices.")
jesdcore.send_sysref_pulse() # Send SYSREF to all devices.
self.log.trace("Setting up JESD204B FPGA RX block.")
jesdcore.init_deframer() # Initialize FPGA's deframer.
self.log.trace("Disabling SYSREF capture blocks.")
self.dac.enable_sysref_capture(False) # Disable DAC's SYSREF capture.
self.adc.enable_sysref_capture(False) # Disable ADC's SYSREF capture.
jesdcore.enable_lmfc(False) # Disable FPGA's SYSREF capture.
time.sleep(0.100) # Allow time for CGS/ILA.
self.log.trace("Verifying JESD204B link status.")
error_flag = False
if not jesdcore.get_framer_status():
self.log.error("JESD204b FPGA Core Framer is not synced!")
error_flag = True
if not self.dac.check_deframer_status():
self.log.error("DAC JESD204B Deframer is not synced!")
error_flag = True
if not self.adc.check_framer_status():
self.log.error("ADC JESD204B Framer is not synced!")
error_flag = True
if not jesdcore.get_deframer_status(True): # TODO: Remove the boolean argument!
self.log.error("JESD204B FPGA Core Deframer is not synced!")
error_flag = True
if error_flag:
raise RuntimeError('JESD204B Link Initialization Failed. See MPM logs for details.')
self.log.info("JESD204B Link Initialization & Training Complete")
def init(self, args):
"""
Run the full initialization sequence. This will bring everything up
from scratch: The LMK, JESD cores, the AD9695, the DAC37J82, and
anything else that is clocking-related.
Depending on the settings, this can take a fair amount of time.
"""
# Input validation on RX margin tests (@ FPGA and DAC)
# By accepting the rx_eyescan/tx_prbs argument being str or bool, one may
# request an eyescan measurement to be performed from either the USRP's
# shell (i.e. using --default-args) or from the host's MPM shell.
perform_rx_eyescan = False
if 'rx_eyescan' in args:
perform_rx_eyescan = (args['rx_eyescan'] == 'True') or (args['rx_eyescan'] == True)
if perform_rx_eyescan:
self.log.trace("Adding RX eye scan PMA enable to JESD args.")
self.JESD_DEFAULT_ARGS["enable_rx_eyescan"] = True
perform_tx_prbs = False
if 'tx_prbs' in args:
perform_tx_prbs = (args['tx_prbs'] == 'True') or (args['tx_prbs'] == True)
# Bringup Sequence.
# 1. Prerequisites (include opening mmaps)
# 2. Initialize LMK and bringup clocks.
# 3. Synchronize DB Clocks.
# 4. Initialize FPGA JESD IP.
# 5. DAC Configuration.
# 6. ADC Configuration.
# 7. JESD204B Initialization.
# 8. CPLD Gain Tables Initialization.
# 1. Prerequisites
# Open FPGA IP (Clock control and JESD core).
self.log.trace("Creating dboard clock control object")
db_clk_control = DboardClockControl(self.rh_class.radio_regs, self.log)
self.log.trace("Creating jesdcore object")
jesdcore = nijesdcore.NIJESDCore(self.rh_class.radio_regs, self.rh_class.slot_idx, **self.JESD_DEFAULT_ARGS)
self.log.trace("Creating gain table object...")
self.gain_table_loader = GainTableRh(
self._spi_ifaces['cpld'],
self._spi_ifaces['cpld_gain_loader'],
self.log)
# 2. Initialize LMK and bringup clocks.
# Disable FPGA MMCM's outputs, and assert its reset.
db_clk_control.reset_mmcm()
# Always place the JESD204b cores in reset before modifying the clocks,
# otherwise high power or erroneous conditions could exist in the FPGA!
jesdcore.reset()
# Configure and bringup the LMK's clocks.
self.log.trace("Initializing LMK...")
self.rh_class.lmk = self._init_lmk(
self._spi_ifaces['lmk'],
self.rh_class.ref_clock_freq,
self.rh_class.sampling_clock_rate,
self._spi_ifaces['phase_dac'],
self.INIT_PHASE_DAC_WORD,
self.PHASE_DAC_SPI_ADDR
)
self.log.trace("LMK Initialized!")
# Deassert FPGA's MMCM reset, poll for lock, and enable outputs.
db_clk_control.enable_mmcm()
# 3. Synchronize DB Clocks.
# The clock synchronzation driver receives the master_clock_rate, which for
# Rhodium is half the sampling_clock_rate.
self._sync_db_clock(
self.rh_class.radio_regs,
self.rh_class.ref_clock_freq,
self.rh_class.sampling_clock_rate / 2,
args)
# 4. DAC Configuration.
self.dac.config()
# 5. ADC Configuration.
self.adc.config()
# 6-7. JESD204B Initialization.
self.init_jesd(jesdcore, self.rh_class.sampling_clock_rate)
# [Optional] Perform RX eyescan.
if perform_rx_eyescan:
self.log.info("Performing RX eye scan on ADC to FPGA link...")
self._rx_eyescan(jesdcore, args)
# [Optional] Perform TX PRBS test.
if perform_tx_prbs:
self.log.info("Performing TX PRBS-31 test on FPGA to DAC link...")
self._tx_prbs_test(jesdcore, args)
jesdcore = None # We are done using the jesdcore at this point.
# 8. CPLD Gain Tables Initialization.
self.gain_table_loader.init()
return True
##########################################################################
# JESD204B RX margin testing
##########################################################################
def _rx_eyescan(self, jesdcore, args):
"""
This function creates an eyescan object to perform this measurement with the
given configuration and lanes.
Parameters:
prescale -> Controls the prescaling of the sample count to keep both sample
count and error count in reasonable precision.
Valid values: from 0 to 31.
"""
# The following constants must be defined according to GTs configuration
# for each project. For further details, refer to the eyescan.py file.
# For Rhodium, these parameters are based on the JESD core.
rxout_div = 2
rx_int_datawidth = 20
eq_mode = 'LPM'
# The following variables define the GTs to be scanned and the range of the
# measurement.
prescale = 0
scan_lanes = [0, 1, 2, 3]
hor_range = {'start':-32 , 'stop':32 , 'step': 2}
ver_range = {'start':-127, 'stop':127, 'step': 2}
# Set default configuration values for Rhodium when the user is not intentionally
# changing the constants/variables default values.
for key in ('rxout_div', 'rx_int_datawidth', 'eq_mode',
'prescale', 'scan_lanes', 'hor_range', 'ver_range'):
if key not in args:
self.log.trace("Setting Rh default value for {0}... val: {1}"
.format(key, locals()[key]))
args[key] = locals()[key]
#
# Create an eyescan object.
assert jesdcore is not None
eyescan_tool = EyeScanTool(jesdcore, self.slot_idx, **args)
# Put the ADC in pseudorandom test mode.
adc_regs = self._spi_ifaces['adc']
# test_val = adc_regs.peek8(0x0550)
# adc_regs.poke8(0x0550, 0x05)
test_val = adc_regs.peek8(0x0573)
adc_regs.poke8(0x0573, 0x13)
# Perform eye scan on given lanes and range.
file_name = eyescan_tool.eyescan_full_scan(args['scan_lanes'],
args['hor_range'], args['ver_range'])
# Do some housekeeping...
# adc_regs.poke8(0x0550, test_val) # Enable normal operation.
adc_regs.poke8(0x0573, test_val) # Enable normal operation.
adc_regs.poke8(0x0000, 0x81) # Reset.
eyescan_tool = None
return file_name
def _tx_prbs_test(self, jesdcore, args):
"""
This function allows to test the PRBS-31 pattern at the DAC.
"""
def _test_lanes(**tx_settings):
"""
This methods enables, monitors, and disables the PRBS-31 test.
"""
results = []
jesdcore.adjust_tx_phy(**tx_phy_settings)
self.log.info("Testing TX PHY settings: tx_driver_swing=0b{0:04b}"
" tx_precursor=0b{1:05b}"
" tx_postcursor=0b{2:05b}"
.format(tx_phy_settings["tx_driver_swing"],
tx_phy_settings["tx_precursor"],
tx_phy_settings["tx_postcursor"]))
# Enable the GTs TX pattern generator in PRBS-31 mode.
jesdcore.set_pattern_gen(mode='PRBS-31')
# Monitor each receive lane at DAC.
for lane_num in range(0, 4):
self.dac.test_mode(mode='PRBS-31', lane=lane_num) # Enable PRBS test mode.
number_of_failures = 0
for _ in range(0, POLLS_PER_GT):
time.sleep(WAIT_TIME_PER_POLL)
alarm_pin_dac = self.rh_class.cpld.get_dac_alarm()
if alarm_pin_dac:
number_of_failures += 1
results.append(number_of_failures)
if number_of_failures > 0:
self.log.error("PRBS-31 test for DAC lane {0} failed {1}/{2}!"
.format(lane_num, number_of_failures, POLLS_PER_GT))
else:
self.log.info("PRBS-31 test for DAC lane {0} passed!"
.format(lane_num))
self.dac.test_mode(mode='OFF', lane=lane_num) # Disable PRBS test mode.
# Disable TX pattern generator at FPGA
jesdcore.set_pattern_gen(mode='OFF')
return results
#
WAIT_TIME_PER_POLL = 0.001 # in seconds.
POLLS_PER_GT = 100
# Create the CSV file.
f = open('tx_prbs_sweep.csv', 'w')
f.write("Swing,Precursor,Postcursor,Polls,Failures 0,Failures 1,Failures 2,Failures 3\n")
# Default TX PHY settings.
tx_phy_settings = {"tx_driver_swing": 0b1111, # See UG476, TXDIFFCTRL
"tx_precursor" : 0b00000, # See UG476, TXPRECURSOR
"tx_postcursor" : 0b00000} # See UG476, TXPOSTCURSOR
# Define sweep ranges.
DEFAULT_SWING_RANGE = {'start': 0b0000, 'stop': 0b1111 + 0b1, 'step': 1}
DEFAULT_CURSOR_RANGE = {'start': 0b00000, 'stop': 0b11111 + 0b1, 'step': 2}
swing_range = args.get("swing_range", DEFAULT_SWING_RANGE)
precursor_range = args.get("precursor_range", DEFAULT_CURSOR_RANGE)
postcursor_range = args.get("postcursor_range", DEFAULT_CURSOR_RANGE)
# Test the TX margin across multiple PHY settings.
for swing in range(swing_range['start'], swing_range['stop'], swing_range['step']):
tx_phy_settings["tx_driver_swing"] = swing
for precursor in range(precursor_range['start'], precursor_range['stop'], precursor_range['step']):
tx_phy_settings["tx_precursor"] = precursor
for postcursor in range(postcursor_range['start'], postcursor_range['stop'], postcursor_range['step']):
tx_phy_settings["tx_postcursor"] = postcursor
results = _test_lanes(**tx_phy_settings)
f.write("{},{},{},{},{},{},{},{}\n".format(
tx_phy_settings["tx_driver_swing"],
tx_phy_settings["tx_precursor"],
tx_phy_settings["tx_postcursor"],
POLLS_PER_GT, results[0], results[1], results[2], results[3]))
# Housekeeping...
f.close()
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