dev: Add support for i2c devices
This patch adds an I2C bus and base device. I2C is used to connect a variety of sensors, and this patch serves as a starting point to enable a range of I2C devices.
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5 changed files with 544 additions and 0 deletions
51
src/dev/I2C.py
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51
src/dev/I2C.py
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# Copyright (c) 2012 ARM Limited
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# All rights reserved.
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#
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# The license below extends only to copyright in the software and shall
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# not be construed as granting a license to any other intellectual
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# property including but not limited to intellectual property relating
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# to a hardware implementation of the functionality of the software
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# licensed hereunder. You may use the software subject to the license
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|
# terms below provided that you ensure that this notice is replicated
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# unmodified and in its entirety in all distributions of the software,
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# modified or unmodified, in source code or in binary form.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are
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# met: redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer;
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# redistributions in binary form must reproduce the above copyright
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|
# notice, this list of conditions and the following disclaimer in the
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# documentation and/or other materials provided with the distribution;
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# neither the name of the copyright holders nor the names of its
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# contributors may be used to endorse or promote products derived from
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# this software without specific prior written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#
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# Authors: Peter Enns
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from m5.SimObject import SimObject
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from m5.params import *
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from Device import BasicPioDevice
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class I2CDevice(SimObject):
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type = 'I2CDevice'
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cxx_header = "dev/i2cdev.hh"
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abstract = True
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i2c_addr = Param.UInt8("Address of device on i2c bus")
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class I2CBus(BasicPioDevice):
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type = 'I2CBus'
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cxx_header = "dev/i2cbus.hh"
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devices = VectorParam.I2CDevice([], "Devices")
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@ -43,6 +43,7 @@ SimObject('BadDevice.py')
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SimObject('CopyEngine.py')
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SimObject('CopyEngine.py')
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SimObject('DiskImage.py')
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SimObject('DiskImage.py')
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SimObject('Ethernet.py')
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SimObject('Ethernet.py')
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SimObject('I2C.py')
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SimObject('Ide.py')
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SimObject('Ide.py')
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SimObject('Pci.py')
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SimObject('Pci.py')
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SimObject('Platform.py')
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SimObject('Platform.py')
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@ -61,6 +62,7 @@ Source('etherint.cc')
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Source('etherlink.cc')
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Source('etherlink.cc')
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Source('etherpkt.cc')
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Source('etherpkt.cc')
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Source('ethertap.cc')
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Source('ethertap.cc')
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Source('i2cbus.cc')
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Source('i8254xGBe.cc')
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Source('i8254xGBe.cc')
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Source('ide_ctrl.cc')
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Source('ide_ctrl.cc')
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Source('ide_disk.cc')
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Source('ide_disk.cc')
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242
src/dev/i2cbus.cc
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242
src/dev/i2cbus.cc
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/*
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* Copyright (c) 2012 ARM Limited
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* All rights reserved
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*
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* The license below extends only to copyright in the software and shall
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* not be construed as granting a license to any other intellectual
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|
* property including but not limited to intellectual property relating
|
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|
* to a hardware implementation of the functionality of the software
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|
* licensed hereunder. You may use the software subject to the license
|
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|
* terms below provided that you ensure that this notice is replicated
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* unmodified and in its entirety in all distributions of the software,
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* modified or unmodified, in source code or in binary form.
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|
*
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|
* Redistribution and use in source and binary forms, with or without
|
||||||
|
* modification, are permitted provided that the following conditions are
|
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|
* 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
|
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|
* contributors may be used to endorse or promote products derived from
|
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|
* this software without specific prior written permission.
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|
*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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|
* "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
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|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
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|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||||
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
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|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
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|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* Authors: Peter Enns
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*/
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#include "dev/i2cbus.hh"
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#include "debug/Checkpoint.hh"
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#include "mem/packet_access.hh"
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// clang complains about std::set being overloaded with Packet::set if
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// we open up the entire namespace std
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using std::vector;
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using std::map;
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/**
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* 4KB - see e.g.
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* http://infocenter.arm.com/help/topic/com.arm.doc.dui0440b/Bbajihec.html
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*/
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I2CBus::I2CBus(const I2CBusParams *p)
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: BasicPioDevice(p, 0xfff), scl(1), sda(1), state(IDLE), currBit(7),
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i2cAddr(0x00), message(0x00)
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{
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vector<I2CDevice*> devs = p->devices;
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for (auto d : p->devices) {
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devices[d->i2cAddr()] = d;
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}
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}
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/**
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* Reads will always be to SB_CONTROLS. The kernel wants to know the state
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* of sda and scl.
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*/
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Tick
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I2CBus::read(PacketPtr pkt)
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{
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assert(pkt->getAddr() == pioAddr + SB_CONTROLS);
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pkt->set<uint8_t>((sda << 1) | scl);
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pkt->makeAtomicResponse();
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return pioDelay;
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}
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/**
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* The default i2c bus driver used by the realview pbx board writes to
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* this device one bit at a time. To facilitate making new i2c devices,
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* i2cBus::write takes care of the low-level details of the i2c protocol.
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* See the I2C Specification [1] for a detailed description of the
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* protocol.
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*
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* [1] - http://www.nxp.com/documents/user_manual/UM10204.pdf
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*/
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Tick
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I2CBus::write(PacketPtr pkt)
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{
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assert(pkt->getAddr() == pioAddr + SB_CONTROLS ||
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pkt->getAddr() == pioAddr + SB_CONTROLC);
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updateSignals(pkt);
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// Check if the bus master is starting a new transmission.
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if (isStart(pkt)) {
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state = RECEIVING_ADDR;
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message = 0x00;
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currBit = 7;
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/* Most i2c devices expect something special (e.g., command,
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* register address) in the first byte they receive so they
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* must be notified somehow that this is a new transmission.
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*/
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for (auto& d : devices) {
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d.second->i2cStart();
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}
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return pioDelay;
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}
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// Check if the bus master is ending a transmission.
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if (isEnd(pkt)) {
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state = IDLE;
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return pioDelay;
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}
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// Only change state when the clock is transitioning from low to high.
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// This may not perfectly mimic physical i2c devices but the important
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// part is to only do the following once per clock cycle.
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if (isClockSet(pkt)) {
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switch (state) {
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case RECEIVING_ADDR:
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if (currBit >= 0) {
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message |= sda << currBit;
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currBit--;
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} else {
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i2cAddr = message >> 1;
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assert(devices.find(i2cAddr) != devices.end());
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if (message & 0x01) {
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state = SENDING_DATA;
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message = devices[i2cAddr]->read();
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} else {
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state = RECEIVING_DATA;
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message = 0x00;
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}
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currBit = 7;
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sda = 0; /* Ack */
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}
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break;
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case RECEIVING_DATA:
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if (currBit >= 0) {
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message |= sda << currBit;
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currBit--;
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} else {
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devices[i2cAddr]->write(message);
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message = 0x00;
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currBit = 7;
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sda = 0; /* Ack */
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}
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break;
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case SENDING_DATA:
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if (currBit >= 0) {
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sda = (message >> currBit) & 0x01;
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currBit--;
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} else {
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if (!sda) /* Check for ack from the bus master. */
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message = devices[i2cAddr]->read();
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currBit = 7;
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}
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break;
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case IDLE:
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default:
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panic("Invalid state on posedge of clock in I2CBus::write.\n");
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break;
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}
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}
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return pioDelay;
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}
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void
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I2CBus::updateSignals(PacketPtr pkt)
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{
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uint8_t msg = pkt->get<uint8_t>();
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Addr daddr = pkt->getAddr() - pioAddr;
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switch (daddr) {
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case SB_CONTROLS:
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scl = (msg & 1) ? 1 : scl;
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sda = (msg & 2) ? 1 : sda;
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break;
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case SB_CONTROLC:
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scl = (msg & 1) ? 0 : scl;
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sda = (msg & 2) ? 0 : sda;
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break;
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default:
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break;
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}
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}
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bool
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I2CBus::isClockSet(PacketPtr pkt) const
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{
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uint8_t msg = pkt->get<uint8_t>();
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Addr daddr = pkt->getAddr() - pioAddr;
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return daddr == SB_CONTROLS && (msg & 1);
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}
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bool
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I2CBus::isStart(PacketPtr pkt) const
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{
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uint8_t msg = pkt->get<uint8_t>();
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Addr daddr = pkt->getAddr() - pioAddr;
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return scl && (msg & 2) && daddr == SB_CONTROLC;
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}
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bool
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I2CBus::isEnd(PacketPtr pkt) const
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{
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uint8_t msg = pkt->get<uint8_t>();
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Addr daddr = pkt->getAddr() - pioAddr;
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return scl && (msg & 2) && daddr == SB_CONTROLS;
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}
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void
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I2CBus::serialize(std::ostream &os)
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{
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DPRINTF(Checkpoint, "Serializing I2C bus.\n");
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SERIALIZE_SCALAR(scl);
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SERIALIZE_SCALAR(sda);
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SERIALIZE_ENUM(state);
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SERIALIZE_SCALAR(currBit);
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SERIALIZE_SCALAR(i2cAddr);
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SERIALIZE_SCALAR(message);
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}
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void
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I2CBus::unserialize(Checkpoint *cp, const std::string §ion)
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{
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DPRINTF(Checkpoint, "Unserializing I2C bus.\n");
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UNSERIALIZE_SCALAR(scl);
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UNSERIALIZE_SCALAR(sda);
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UNSERIALIZE_ENUM(state);
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UNSERIALIZE_SCALAR(currBit);
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UNSERIALIZE_SCALAR(i2cAddr);
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UNSERIALIZE_SCALAR(message);
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}
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I2CBus*
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I2CBusParams::create()
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{
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return new I2CBus(this);
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}
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153
src/dev/i2cbus.hh
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153
src/dev/i2cbus.hh
Normal file
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@ -0,0 +1,153 @@
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/*
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* Copyright (c) 2012 ARM Limited
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* All rights reserved
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*
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* The license below extends only to copyright in the software and shall
|
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|
* not be construed as granting a license to any other intellectual
|
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|
* property including but not limited to intellectual property relating
|
||||||
|
* to a hardware implementation of the functionality of the software
|
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|
* licensed hereunder. You may use the software subject to the license
|
||||||
|
* terms below provided that you ensure that this notice is replicated
|
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|
* unmodified and in its entirety in all distributions of the software,
|
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|
* modified or unmodified, in source code or in binary form.
|
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|
*
|
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|
* 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;
|
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|
* neither the name of the copyright holders nor the names of its
|
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|
* contributors may be used to endorse or promote products derived from
|
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|
* this software without specific prior written permission.
|
||||||
|
*
|
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|
* 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
|
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|
* 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
|
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|
* 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.
|
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|
*
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||||||
|
* Authors: Peter Enns
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*/
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/** @file
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* Implementiation of an i2c bus
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*/
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#ifndef __DEV_I2CBUS__
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#define __DEV_I2CBUS__
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#include <map>
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#include "dev/i2cdev.hh"
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#include "dev/io_device.hh"
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#include "params/I2CBus.hh"
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class I2CBus : public BasicPioDevice
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{
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||||||
|
protected:
|
||||||
|
|
||||||
|
enum I2CState {
|
||||||
|
IDLE,
|
||||||
|
RECEIVING_ADDR,
|
||||||
|
RECEIVING_DATA,
|
||||||
|
SENDING_DATA,
|
||||||
|
};
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Read [and Set] serial control bits:
|
||||||
|
* Bit [0] is SCL
|
||||||
|
* Bit [1] is SDA
|
||||||
|
*
|
||||||
|
* http://infocenter.arm.com/help/topic/com.arm.doc.dui0440b/Bbajdjeg.html
|
||||||
|
*/
|
||||||
|
static const int SB_CONTROLS = 0x0;
|
||||||
|
/** Clear control bits. Analogous to SB_CONTROLS */
|
||||||
|
static const int SB_CONTROLC = 0x4;
|
||||||
|
|
||||||
|
/** I2C clock wire (0, 1). */
|
||||||
|
uint8_t scl;
|
||||||
|
/** I2C data wire (0, 1) */
|
||||||
|
uint8_t sda;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* State used by I2CBus::write to determine what stage of an i2c
|
||||||
|
* transmission it is currently in.
|
||||||
|
*/
|
||||||
|
enum I2CState state;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Order of the bit of the current message that is being sent or
|
||||||
|
* received (0 - 7).
|
||||||
|
*/
|
||||||
|
int currBit;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Key used to access a device in the slave devices map. This
|
||||||
|
* is the same address that is specified in kernel board
|
||||||
|
* initialization code (e.g., arch/arm/mach-realview/core.c).
|
||||||
|
*/
|
||||||
|
uint8_t i2cAddr;
|
||||||
|
|
||||||
|
/** 8-bit buffer used to send and receive messages bit by bit. */
|
||||||
|
uint8_t message;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* All the slave i2c devices that are connected to this
|
||||||
|
* bus. Each device has an address that points to the actual
|
||||||
|
* device.
|
||||||
|
*/
|
||||||
|
std::map<uint8_t, I2CDevice*> devices;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Update data (sda) and clock (scl) to match any transitions
|
||||||
|
* specified by pkt.
|
||||||
|
*
|
||||||
|
* @param pkt memory request packet
|
||||||
|
*/
|
||||||
|
void updateSignals(PacketPtr pkt);
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Clock set check
|
||||||
|
*
|
||||||
|
* @param pkt memory request packet
|
||||||
|
* @return true if pkt indicates that scl transition from 0 to 1
|
||||||
|
*/
|
||||||
|
bool isClockSet(PacketPtr pkt) const;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* i2c start signal check
|
||||||
|
*
|
||||||
|
* @param pkt memory request packet
|
||||||
|
* @return true if pkt indicates a new transmission
|
||||||
|
*/
|
||||||
|
bool isStart(PacketPtr pkt) const;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* i2c end signal check
|
||||||
|
*
|
||||||
|
* @param pkt memory request packet
|
||||||
|
* @return true if pkt indicates stopping the current transmission
|
||||||
|
*/
|
||||||
|
bool isEnd(PacketPtr pkt) const;
|
||||||
|
|
||||||
|
public:
|
||||||
|
|
||||||
|
I2CBus(const I2CBusParams* p);
|
||||||
|
|
||||||
|
virtual Tick read(PacketPtr pkt);
|
||||||
|
virtual Tick write(PacketPtr pkt);
|
||||||
|
|
||||||
|
virtual void serialize(std::ostream& os);
|
||||||
|
virtual void unserialize(Checkpoint* cp, const std::string& section);
|
||||||
|
};
|
||||||
|
|
||||||
|
#endif //__DEV_I2CBUS
|
96
src/dev/i2cdev.hh
Normal file
96
src/dev/i2cdev.hh
Normal file
|
@ -0,0 +1,96 @@
|
||||||
|
/*
|
||||||
|
* Copyright (c) 2012 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.*
|
||||||
|
*
|
||||||
|
* Authors: Peter Enns
|
||||||
|
*/
|
||||||
|
|
||||||
|
|
||||||
|
/** @file
|
||||||
|
* All i2c devices should derive from this class.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#ifndef __DEV_I2CDEV__
|
||||||
|
#define __DEV_I2CDEV__
|
||||||
|
|
||||||
|
#include "base/types.hh"
|
||||||
|
#include "params/I2CDevice.hh"
|
||||||
|
#include "sim/sim_object.hh"
|
||||||
|
|
||||||
|
class I2CDevice : public SimObject
|
||||||
|
{
|
||||||
|
|
||||||
|
protected:
|
||||||
|
|
||||||
|
uint8_t _addr;
|
||||||
|
|
||||||
|
public:
|
||||||
|
|
||||||
|
I2CDevice(const I2CDeviceParams* p)
|
||||||
|
: SimObject(p), _addr(p->i2c_addr)
|
||||||
|
{ }
|
||||||
|
|
||||||
|
virtual ~I2CDevice() { }
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Return the next message that the device expects to send. This
|
||||||
|
* will likely have side effects (e.g., incrementing a register
|
||||||
|
* pointer).
|
||||||
|
*
|
||||||
|
* @return 8-bit message the device has been set up to send
|
||||||
|
*/
|
||||||
|
virtual uint8_t read() = 0;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Perform any actions triggered by an i2c write (save msg in a
|
||||||
|
* register, perform an interrupt, update a register pointer or
|
||||||
|
* command register, etc...)
|
||||||
|
*
|
||||||
|
* @param msg 8-bit message from master
|
||||||
|
*/
|
||||||
|
virtual void write(uint8_t msg) = 0;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Perform any initialization necessary for the device when it
|
||||||
|
* received a start signal from the bus master (devices frequently
|
||||||
|
* expect the first write to be a register address)
|
||||||
|
*/
|
||||||
|
virtual void i2cStart() = 0;
|
||||||
|
|
||||||
|
uint8_t i2cAddr() const { return _addr; }
|
||||||
|
|
||||||
|
};
|
||||||
|
|
||||||
|
#endif // __DEV_I2CDEV__
|
Loading…
Reference in a new issue