src/dev/arm/GenericTimer.py - public/gem5 - Git at Google

 # Copyright (c) 2009-2020, 2022 Arm Limited
 # All rights reserved.
 #
 # The license below extends only to copyright in the software and shall
 # not be construed as granting a license to any other intellectual
 # property including but not limited to intellectual property relating
 # to a hardware implementation of the functionality of the software
 # licensed hereunder.  You may use the software subject to the license
 # terms below provided that you ensure that this notice is replicated
 # unmodified and in its entirety in all distributions of the software,
 # modified or unmodified, in source code or in binary form.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met: redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer;
 # 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;
 # neither the name of the copyright holders 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
 # OWNER 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.

 from m5.SimObject import SimObject
 from m5.objects.Device import PioDevice
 from m5.params import Param, MaxAddr, NULL, VectorParam
 from m5.proxy import Parent
 from m5.util import fatal
 from m5.util.fdthelper import FdtNode, FdtProperty, FdtPropertyWords, FdtState


 class SystemCounter(SimObject):
     """
     Shared by both PE-implementations and memory-mapped timers. It provides a
     uniform view of system time through its counter value.

     Reference:
         Arm ARM (ARM DDI 0487E.a)
         D11.1.2 - The system counter
     """

     type = "SystemCounter"
     cxx_header = "dev/arm/generic_timer.hh"
     cxx_class = "gem5::SystemCounter"

     # Maximum of 1004 frequency entries, including end marker
     freqs = VectorParam.UInt32(
         [0x01800000],
         "Frequencies available for the "
         "system counter (in Hz). First element is the base frequency, "
         "following are alternative lower ones which must be exact divisors",
     )

     def generateDtb(self):
         if not self.freqs:
             fatal("No counter frequency to expose in DTB")
         return FdtPropertyWords("clock-frequency", [self.freqs[0]])


 class GenericTimer(SimObject):
     """
     Architected timers per PE in the system. Each of them provides a physical
     counter, a virtual counter and several timers accessible from different
     exception levels and security states.

     Reference:
         Arm ARM (ARM DDI 0487E.a)
         D11.2 - The AArch64 view of the Generic Timer
         G6.2  - The AArch32 view of the Generic Timer
     """

     type = "GenericTimer"
     cxx_header = "dev/arm/generic_timer.hh"
     cxx_class = "gem5::GenericTimer"

     _freq_in_dtb = False

     system = Param.ArmSystem(Parent.any, "system")

     counter = Param.SystemCounter(Parent.any, "Global system counter")

     int_el1_phys = Param.ArmPPI("EL1 physical timer interrupt")
     int_el1_virt = Param.ArmPPI("EL1 virtual timer interrupt")
     int_el2_ns_phys = Param.ArmPPI("EL2 Non-secure physical timer interrupt")
     int_el2_ns_virt = Param.ArmPPI("EL2 Non-secure virtual timer interrupt")
     int_el2_s_phys = Param.ArmPPI("EL2 Secure physical timer interrupt")
     int_el2_s_virt = Param.ArmPPI("EL2 Secure virtual timer interrupt")
     int_el3_phys = Param.ArmPPI("EL3 physical timer interrupt")

     # This value should be in theory initialized by the highest
     # priviledged software. We do this in gem5 to avoid KVM
     # complications (the gem5 firmware won't run at highest EL)
     #
     # PLEASE note: change this parameter only if using the gem5 bootloader
     # Another real world bootloader might be changing the CNTFRQ register
     # value, so this initial value will be discarded
     cntfrq = Param.UInt64(0x1800000, "Value for the CNTFRQ timer register")

     def generateDeviceTree(self, state):
         node = FdtNode("timer")

         node.appendCompatible(
             ["arm,cortex-a15-timer", "arm,armv7-timer", "arm,armv8-timer"]
         )

         gic = self._parent.unproxy(self).gic
         node.append(
             FdtPropertyWords(
                 "interrupts",
                 self.int_el3_phys.generateFdtProperty(gic)
                 + self.int_el1_phys.generateFdtProperty(gic)
                 + self.int_el1_virt.generateFdtProperty(gic)
                 + self.int_el2_ns_phys.generateFdtProperty(gic)
                 + self.int_el2_ns_virt.generateFdtProperty(gic),
             )
         )

         if self._freq_in_dtb:
             node.append(self.counter.unproxy(self).generateDtb())

         yield node


 class GenericTimerFrame(PioDevice):
     """
     Memory-mapped timer frame implementation. Controlled from GenericTimerMem,
     may be used by peripherals without a system register interface.

     Reference:
         Arm ARM (ARM DDI 0487E.a)
         I2.3.2 - The CNTBaseN and CNTEL0BaseN frames
     """

     type = "GenericTimerFrame"
     cxx_header = "dev/arm/generic_timer.hh"
     cxx_class = "gem5::GenericTimerFrame"

     _frame_num = 0

     counter = Param.SystemCounter(Parent.any, "Global system counter")

     cnt_base = Param.Addr("CNTBase register frame base")
     cnt_el0_base = Param.Addr(MaxAddr, "CNTEL0Base register frame base")

     int_phys = Param.ArmSPI("Physical Interrupt")
     int_virt = Param.ArmSPI("Virtual Interrupt")

     def generateDeviceTree(self, state, gic):
         node = FdtNode("frame@{:08x}".format(self.cnt_base.value))
         node.append(FdtPropertyWords("frame-number", self._frame_num))

         ints = self.int_phys.generateFdtProperty(gic)
         if self.int_virt != NULL:
             ints.extend(self.int_virt.generateFdtProperty(gic))
         node.append(FdtPropertyWords("interrupts", ints))

         reg = state.addrCells(self.cnt_base) + state.sizeCells(0x1000)
         if self.cnt_el0_base.value != MaxAddr:
             reg.extend(
                 state.addrCells(self.cnt_el0_base) + state.sizeCells(0x1000)
             )
         node.append(FdtPropertyWords("reg", reg))

         return node


 class GenericTimerMem(PioDevice):
     """
     System level implementation. It provides three main components:
     - Memory-mapped counter module: controls the system timer through the
       CNTControlBase frame, and provides its value through the CNTReadBase frame
     - Memory-mapped timer control module: controls the memory-mapped timers
     - Memory-mapped timers: implementations of the GenericTimer for system
       peripherals

     Reference:
         Arm ARM (ARM DDI 0487E.a)
         I2 - System Level Implementation of the Generic Timer
     """

     type = "GenericTimerMem"
     cxx_header = "dev/arm/generic_timer.hh"
     cxx_class = "gem5::GenericTimerMem"

     _freq_in_dtb = False

     counter = Param.SystemCounter(Parent.any, "Global system counter")

     cnt_control_base = Param.Addr("CNTControlBase register frame base")
     cnt_read_base = Param.Addr("CNTReadBase register frame base")
     cnt_ctl_base = Param.Addr("CNTCTLBase register frame base")

     # Maximum of 8 timer frames
     frames = VectorParam.GenericTimerFrame([], "Memory-mapped timer frames")

     def generateDeviceTree(self, state):
         node = self.generateBasicPioDeviceNode(
             state, "timer", self.cnt_ctl_base, 0x1000
         )
         node.appendCompatible(["arm,armv7-timer-mem"])
         node.append(state.addrCellsProperty())
         node.append(state.sizeCellsProperty())
         node.append(FdtProperty("ranges"))

         if self._freq_in_dtb:
             node.append(self.counter.unproxy(self).generateDtb())

         gic = self._parent.unproxy(self).gic

         for i, frame in enumerate(self.frames):
             frame._frame_num = i
             node.append(frame.generateDeviceTree(state, gic))

         yield node
	# Copyright (c) 2009-2020, 2022 Arm Limited
	# All rights reserved.
	#
	# The license below extends only to copyright in the software and shall
	# not be construed as granting a license to any other intellectual
	# property including but not limited to intellectual property relating
	# to a hardware implementation of the functionality of the software
	# licensed hereunder. You may use the software subject to the license
	# terms below provided that you ensure that this notice is replicated
	# unmodified and in its entirety in all distributions of the software,
	# modified or unmodified, in source code or in binary form.
	#
	# Redistribution and use in source and binary forms, with or without
	# modification, are permitted provided that the following conditions are
	# met: redistributions of source code must retain the above copyright
	# notice, this list of conditions and the following disclaimer;
	# 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;
	# neither the name of the copyright holders 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
	# OWNER 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.

	from m5.SimObject import SimObject
	from m5.objects.Device import PioDevice
	from m5.params import Param, MaxAddr, NULL, VectorParam
	from m5.proxy import Parent
	from m5.util import fatal
	from m5.util.fdthelper import FdtNode, FdtProperty, FdtPropertyWords, FdtState


	class SystemCounter(SimObject):
	"""
	Shared by both PE-implementations and memory-mapped timers. It provides a
	uniform view of system time through its counter value.

	Reference:
	Arm ARM (ARM DDI 0487E.a)
	D11.1.2 - The system counter
	"""

	type = "SystemCounter"
	cxx_header = "dev/arm/generic_timer.hh"
	cxx_class = "gem5::SystemCounter"

	# Maximum of 1004 frequency entries, including end marker
	freqs = VectorParam.UInt32(
	[0x01800000],
	"Frequencies available for the "
	"system counter (in Hz). First element is the base frequency, "
	"following are alternative lower ones which must be exact divisors",
	)

	def generateDtb(self):
	if not self.freqs:
	fatal("No counter frequency to expose in DTB")
	return FdtPropertyWords("clock-frequency", [self.freqs[0]])


	class GenericTimer(SimObject):
	"""
	Architected timers per PE in the system. Each of them provides a physical
	counter, a virtual counter and several timers accessible from different
	exception levels and security states.

	Reference:
	Arm ARM (ARM DDI 0487E.a)
	D11.2 - The AArch64 view of the Generic Timer
	G6.2 - The AArch32 view of the Generic Timer
	"""

	type = "GenericTimer"
	cxx_header = "dev/arm/generic_timer.hh"
	cxx_class = "gem5::GenericTimer"

	_freq_in_dtb = False

	system = Param.ArmSystem(Parent.any, "system")

	counter = Param.SystemCounter(Parent.any, "Global system counter")

	int_el1_phys = Param.ArmPPI("EL1 physical timer interrupt")
	int_el1_virt = Param.ArmPPI("EL1 virtual timer interrupt")
	int_el2_ns_phys = Param.ArmPPI("EL2 Non-secure physical timer interrupt")
	int_el2_ns_virt = Param.ArmPPI("EL2 Non-secure virtual timer interrupt")
	int_el2_s_phys = Param.ArmPPI("EL2 Secure physical timer interrupt")
	int_el2_s_virt = Param.ArmPPI("EL2 Secure virtual timer interrupt")
	int_el3_phys = Param.ArmPPI("EL3 physical timer interrupt")

	# This value should be in theory initialized by the highest
	# priviledged software. We do this in gem5 to avoid KVM
	# complications (the gem5 firmware won't run at highest EL)
	#
	# PLEASE note: change this parameter only if using the gem5 bootloader
	# Another real world bootloader might be changing the CNTFRQ register
	# value, so this initial value will be discarded
	cntfrq = Param.UInt64(0x1800000, "Value for the CNTFRQ timer register")

	def generateDeviceTree(self, state):
	node = FdtNode("timer")

	node.appendCompatible(
	["arm,cortex-a15-timer", "arm,armv7-timer", "arm,armv8-timer"]
	)

	gic = self._parent.unproxy(self).gic
	node.append(
	FdtPropertyWords(
	"interrupts",
	self.int_el3_phys.generateFdtProperty(gic)
	+ self.int_el1_phys.generateFdtProperty(gic)
	+ self.int_el1_virt.generateFdtProperty(gic)
	+ self.int_el2_ns_phys.generateFdtProperty(gic)
	+ self.int_el2_ns_virt.generateFdtProperty(gic),
	)
	)

	if self._freq_in_dtb:
	node.append(self.counter.unproxy(self).generateDtb())

	yield node


	class GenericTimerFrame(PioDevice):
	"""
	Memory-mapped timer frame implementation. Controlled from GenericTimerMem,
	may be used by peripherals without a system register interface.

	Reference:
	Arm ARM (ARM DDI 0487E.a)
	I2.3.2 - The CNTBaseN and CNTEL0BaseN frames
	"""

	type = "GenericTimerFrame"
	cxx_header = "dev/arm/generic_timer.hh"
	cxx_class = "gem5::GenericTimerFrame"

	_frame_num = 0

	counter = Param.SystemCounter(Parent.any, "Global system counter")

	cnt_base = Param.Addr("CNTBase register frame base")
	cnt_el0_base = Param.Addr(MaxAddr, "CNTEL0Base register frame base")

	int_phys = Param.ArmSPI("Physical Interrupt")
	int_virt = Param.ArmSPI("Virtual Interrupt")

	def generateDeviceTree(self, state, gic):
	node = FdtNode("frame@{:08x}".format(self.cnt_base.value))
	node.append(FdtPropertyWords("frame-number", self._frame_num))

	ints = self.int_phys.generateFdtProperty(gic)
	if self.int_virt != NULL:
	ints.extend(self.int_virt.generateFdtProperty(gic))
	node.append(FdtPropertyWords("interrupts", ints))

	reg = state.addrCells(self.cnt_base) + state.sizeCells(0x1000)
	if self.cnt_el0_base.value != MaxAddr:
	reg.extend(
	state.addrCells(self.cnt_el0_base) + state.sizeCells(0x1000)
	)
	node.append(FdtPropertyWords("reg", reg))

	return node


	class GenericTimerMem(PioDevice):
	"""
	System level implementation. It provides three main components:
	- Memory-mapped counter module: controls the system timer through the
	CNTControlBase frame, and provides its value through the CNTReadBase frame
	- Memory-mapped timer control module: controls the memory-mapped timers
	- Memory-mapped timers: implementations of the GenericTimer for system
	peripherals

	Reference:
	Arm ARM (ARM DDI 0487E.a)
	I2 - System Level Implementation of the Generic Timer
	"""

	type = "GenericTimerMem"
	cxx_header = "dev/arm/generic_timer.hh"
	cxx_class = "gem5::GenericTimerMem"

	_freq_in_dtb = False

	counter = Param.SystemCounter(Parent.any, "Global system counter")

	cnt_control_base = Param.Addr("CNTControlBase register frame base")
	cnt_read_base = Param.Addr("CNTReadBase register frame base")
	cnt_ctl_base = Param.Addr("CNTCTLBase register frame base")

	# Maximum of 8 timer frames
	frames = VectorParam.GenericTimerFrame([], "Memory-mapped timer frames")

	def generateDeviceTree(self, state):
	node = self.generateBasicPioDeviceNode(
	state, "timer", self.cnt_ctl_base, 0x1000
	)
	node.appendCompatible(["arm,armv7-timer-mem"])
	node.append(state.addrCellsProperty())
	node.append(state.sizeCellsProperty())
	node.append(FdtProperty("ranges"))

	if self._freq_in_dtb:
	node.append(self.counter.unproxy(self).generateDtb())

	gic = self._parent.unproxy(self).gic

	for i, frame in enumerate(self.frames):
	frame._frame_num = i
	node.append(frame.generateDeviceTree(state, gic))

	yield node