#
#  Copyright (c) 2015 Advanced Micro Devices, Inc.
#  All rights reserved.
#
#  For use for simulation and test purposes only
#
#  Redistribution and use in source and binary forms, with or without
#  modification, are permitted provided that the following conditions are met:
#
#  1. Redistributions of source code must retain the above copyright notice,
#  this list of conditions and the following disclaimer.
#
#  2. Redistributions in binary form must reproduce the above copyright notice,
#  this list of conditions and the following disclaimer in the documentation
#  and/or other materials provided with the distribution.
#
#  3. Neither the name of the copyright holder nor the names of its contributors
#  may be used to endorse or promote products derived from this software
#  without specific prior written permission.
#
#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
#  POSSIBILITY OF SUCH DAMAGE.
#
#  Author: Brad Beckmann
#

import m5
from m5.objects import *
from m5.defines import buildEnv
from m5.util import addToPath
import os, argparse, sys, math, glob

m5.util.addToPath('../configs/')

from ruby import Ruby
from common import Options
from common import GPUTLBOptions, GPUTLBConfig

def run_test(root):
    """gpu test requires a specialized run_test implementation to set up the
    mmio space."""

    # instantiate configuration
    m5.instantiate()

    # Now that the system has been constructed, setup the mmio space
    root.system.cpu[0].workload[0].map(0x10000000, 0x200000000, 4096)

    # simulate until program terminates
    exit_event = m5.simulate(maxtick)
    print('Exiting @ tick', m5.curTick(), 'because', exit_event.getCause())

parser = argparse.ArgumentParser()
Options.addCommonOptions(parser)
Options.addSEOptions(parser)

parser.add_argument(
    "-k", "--kernel-files",
    help="file(s) containing GPU kernel code (colon separated)")
parser.add_argument(
    "-u", "--num-compute-units", type=int, default=2,
    help="number of GPU compute units"),
parser.add_argument(
    "--num-cp", type=int, default=0,
    help="Number of GPU Command Processors (CP)")
parser.add_argument(
    "--simds-per-cu", type=int, default=4, help="SIMD units" \
    "per CU")
parser.add_argument(
    "--cu-per-sqc", type=int, default=4, help="number of CUs" \
    "sharing an SQC (icache, and thus icache TLB)")
parser.add_argument(
    "--wf-size", type=int, default=64,
    help="Wavefront size(in workitems)")
parser.add_argument(
    "--wfs-per-simd", type=int, default=8, help="Number of " \
    "WF slots per SIMD")
parser.add_argument(
    "--sp-bypass-path-length", type=int, default=4,
    help="Number of stages of bypass path in vector ALU for Single "
    "Precision ops")
parser.add_argument(
    "--dp-bypass-path-length", type=int, default=4,
    help="Number of stages of bypass path in vector ALU for Double "
    "Precision ops")
parser.add_argument(
    "--issue-period", type=int, default=4,
    help="Number of cycles per vector instruction issue period")
parser.add_argument(
    "--glbmem-wr-bus-width", type=int, default=32,
    help="VGPR to Coalescer (Global Memory) data bus width in bytes")
parser.add_argument(
    "--glbmem-rd-bus-width", type=int, default=32,
    help="Coalescer to VGPR (Global Memory) data bus width in bytes")
parser.add_argument(
    "--shr-mem-pipes-per-cu", type=int, default=1, \
    help="Number of Shared Memory pipelines per CU")
parser.add_argument(
    "--glb-mem-pipes-per-cu", type=int, default=1, \
    help="Number of Global Memory pipelines per CU")
parser.add_argument(
    "--vreg-file-size", type=int, default=2048,
    help="number of physical vector registers per SIMD")
parser.add_argument(
    "--bw-scalor", type=int, default=0,
    help="bandwidth scalor for scalability analysis")
parser.add_argument(
    "--CPUClock", type=str, default="2GHz",
    help="CPU clock")
parser.add_argument(
    "--GPUClock", type=str, default="1GHz",
    help="GPU clock")
parser.add_argument(
    "--cpu-voltage", action="store", type=str,
    default='1.0V',
    help = """CPU  voltage domain""")
parser.add_argument(
    "--gpu-voltage", action="store", type=str,
    default='1.0V',
    help = """CPU  voltage domain""")
parser.add_argument(
    "--CUExecPolicy", type=str, default="OLDEST-FIRST",
    help="WF exec policy (OLDEST-FIRST, ROUND-ROBIN)")
parser.add_argument(
    "--xact-cas-mode", action="store_true",
    help="enable load_compare mode (transactional CAS)")
parser.add_argument(
    "--SegFaultDebug",action="store_true",
    help="checks for GPU seg fault before TLB access")
parser.add_argument(
    "--LocalMemBarrier",action="store_true",
    help="Barrier does not wait for writethroughs to complete")
parser.add_argument(
    "--countPages", action="store_true",
    help="Count Page Accesses and output in per-CU output files")
parser.add_argument(
    "--TLB-prefetch", type=int, help = "prefetch depth for"\
    "TLBs")
parser.add_argument(
    "--pf-type", type=str, help="type of prefetch: "\
    "PF_CU, PF_WF, PF_PHASE, PF_STRIDE")
parser.add_argument("--pf-stride", type=int, help="set prefetch stride")
parser.add_argument(
    "--numLdsBanks", type=int, default=32,
    help="number of physical banks per LDS module")
parser.add_argument(
    "--ldsBankConflictPenalty", type=int, default=1,
    help="number of cycles per LDS bank conflict")

# Add the ruby specific and protocol specific options
Ruby.define_options(parser)

GPUTLBOptions.tlb_options(parser)

args = parser.parse_args()

# The GPU cache coherence protocols only work with the backing store
args.access_backing_store = True

# Currently, the sqc (I-Cache of GPU) is shared by
# multiple compute units(CUs). The protocol works just fine
# even if sqc is not shared. Overriding this option here
# so that the user need not explicitly set this (assuming
# sharing sqc is the common usage)
n_cu = args.num_compute_units
num_sqc = int(math.ceil(float(n_cu) / args.cu_per_sqc))
args.num_sqc = num_sqc # pass this to Ruby

########################## Creating the GPU system ########################
# shader is the GPU
shader = Shader(n_wf = args.wfs_per_simd,
                clk_domain = SrcClockDomain(
                    clock = args.GPUClock,
                    voltage_domain = VoltageDomain(
                        voltage = args.gpu_voltage)),
                timing = True)

# GPU_RfO(Read For Ownership) implements SC/TSO memory model.
# Other GPU protocols implement release consistency at GPU side.
# So, all GPU protocols other than GPU_RfO should make their writes
# visible to the global memory and should read from global memory
# during kernal boundary. The pipeline initiates(or do not initiate)
# the acquire/release operation depending on this impl_kern_boundary_sync
# flag. This flag=true means pipeline initiates a acquire/release operation
# at kernel boundary.
if buildEnv['PROTOCOL'] == 'GPU_RfO':
    shader.impl_kern_boundary_sync = False
else:
    shader.impl_kern_boundary_sync = True

# Switching off per-lane TLB by default
per_lane = False
if args.TLB_config == "perLane":
    per_lane = True

# List of compute units; one GPU can have multiple compute units
compute_units = []
for i in range(n_cu):
    compute_units.append(ComputeUnit(cu_id = i, perLaneTLB = per_lane,
                                     num_SIMDs = args.simds_per_cu,
                                     wfSize = args.wf_size,
                                     spbypass_pipe_length = \
                                     args.sp_bypass_path_length,
                                     dpbypass_pipe_length = \
                                     args.dp_bypass_path_length,
                                     issue_period = args.issue_period,
                                     coalescer_to_vrf_bus_width = \
                                     args.glbmem_rd_bus_width,
                                     vrf_to_coalescer_bus_width = \
                                     args.glbmem_wr_bus_width,
                                     num_global_mem_pipes = \
                                     args.glb_mem_pipes_per_cu,
                                     num_shared_mem_pipes = \
                                     args.shr_mem_pipes_per_cu,
                                     n_wf = args.wfs_per_simd,
                                     execPolicy = args.CUExecPolicy,
                                     xactCasMode = args.xact_cas_mode,
                                     debugSegFault = args.SegFaultDebug,
                                     functionalTLB = True,
                                     localMemBarrier = args.LocalMemBarrier,
                                     countPages = args.countPages,
                                     localDataStore = \
                                     LdsState(banks = args.numLdsBanks,
                                              bankConflictPenalty = \
                                              args.ldsBankConflictPenalty)))
    wavefronts = []
    vrfs = []
    for j in range(args.simds_per_cu):
        for k in range(int(shader.n_wf)):
            wavefronts.append(Wavefront(simdId = j, wf_slot_id = k))
        vrfs.append(VectorRegisterFile(simd_id=j,
                              num_regs_per_simd=args.vreg_file_size))
    compute_units[-1].wavefronts = wavefronts
    compute_units[-1].vector_register_file = vrfs
    if args.TLB_prefetch:
        compute_units[-1].prefetch_depth = args.TLB_prefetch
        compute_units[-1].prefetch_prev_type = args.pf_type

    # attach the LDS and the CU to the bus (actually a Bridge)
    compute_units[-1].ldsPort = compute_units[-1].ldsBus.slave
    compute_units[-1].ldsBus.master = compute_units[-1].localDataStore.cuPort

# Attach compute units to GPU
shader.CUs = compute_units

# this is a uniprocessor only test, thus the shader is the second index in the
# list of "system.cpus"
args.num_cpus = 1
shader_idx = 1
cpu = TimingSimpleCPU(cpu_id=0)

########################## Creating the GPU dispatcher ########################
# Dispatcher dispatches work from host CPU to GPU
host_cpu = cpu
dispatcher = GpuDispatcher()

# Currently does not test for command processors
cpu_list = [cpu] + [shader] + [dispatcher]

system = System(cpu = cpu_list,
                mem_ranges = [AddrRange(args.mem_size)],
                mem_mode = 'timing',
                workload = SEWorkload())

# Dummy voltage domain for all our clock domains
system.voltage_domain = VoltageDomain(voltage = args.sys_voltage)
system.clk_domain = SrcClockDomain(clock = '1GHz',
                                   voltage_domain = system.voltage_domain)

# Create a seperate clock domain for components that should run at
# CPUs frequency
system.cpu[0].clk_domain = SrcClockDomain(clock = '2GHz',
                                          voltage_domain = \
                                          system.voltage_domain)

# configure the TLB hierarchy
GPUTLBConfig.config_tlb_hierarchy(args, system, shader_idx)

# create Ruby system
system.piobus = IOXBar(width=32, response_latency=0,
                       frontend_latency=0, forward_latency=0)
Ruby.create_system(args, None, system)

# Create a separate clock for Ruby
system.ruby.clk_domain = SrcClockDomain(clock = args.ruby_clock,
                                        voltage_domain = system.voltage_domain)

# create the interrupt controller
cpu.createInterruptController()

#
# Tie the cpu cache ports to the ruby cpu ports and
# physmem, respectively
#
cpu.connectAllPorts(system.ruby._cpu_ports[0])
system.ruby._cpu_ports[0].mem_master_port = system.piobus.slave

# attach CU ports to Ruby
# Because of the peculiarities of the CP core, you may have 1 CPU but 2
# sequencers and thus 2 _cpu_ports created. Your GPUs shouldn't be
# hooked up until after the CP. To make this script generic, figure out
# the index as below, but note that this assumes there is one sequencer
# per compute unit and one sequencer per SQC for the math to work out
# correctly.
gpu_port_idx = len(system.ruby._cpu_ports) \
               - args.num_compute_units - args.num_sqc
gpu_port_idx = gpu_port_idx - args.num_cp * 2

wavefront_size = args.wf_size
for i in range(n_cu):
    # The pipeline issues wavefront_size number of uncoalesced requests
    # in one GPU issue cycle. Hence wavefront_size mem ports.
    for j in range(wavefront_size):
        system.cpu[shader_idx].CUs[i].memory_port[j] = \
                  system.ruby._cpu_ports[gpu_port_idx].slave[j]
    gpu_port_idx += 1

for i in range(n_cu):
    if i > 0 and not i % args.cu_per_sqc:
        gpu_port_idx += 1
    system.cpu[shader_idx].CUs[i].sqc_port = \
            system.ruby._cpu_ports[gpu_port_idx].slave
gpu_port_idx = gpu_port_idx + 1

# Current regression tests do not support the command processor
assert(args.num_cp == 0)

# connect dispatcher to the system.piobus
dispatcher.pio = system.piobus.master
dispatcher.dma = system.piobus.slave

################# Connect the CPU and GPU via GPU Dispatcher ###################
# CPU rings the GPU doorbell to notify a pending task
# using this interface.
# And GPU uses this interface to notify the CPU of task completion
# The communcation happens through emulated driver.

# Note this implicit setting of the cpu_pointer, shader_pointer and tlb array
# parameters must be after the explicit setting of the System cpu list
shader.cpu_pointer = host_cpu
dispatcher.cpu = host_cpu
dispatcher.shader_pointer = shader

# -----------------------
# run simulation
# -----------------------

root = Root(full_system = False, system = system)
m5.ticks.setGlobalFrequency('1THz')
root.system.mem_mode = 'timing'
