gem5/dev/uart.cc
Nathan Binkert 43a9caa221 expose variables for number of global events per simulated second,
millisecond, microsecond, etc. so that the user can explicitly
convert between system ticks and time and know what sorts of
expensive operations are being used for that conversion.

arch/alpha/alpha_tru64_process.cc:
arch/alpha/pseudo_inst.cc:
dev/etherdump.cc:
dev/etherlink.cc:
dev/ns_gige.cc:
dev/sinic.cc:
dev/tsunami_io.cc:
dev/uart.cc:
sim/stat_control.cc:
sim/syscall_emul.hh:
    Use the new variables for getting the event clock
dev/etherdump.hh:
    delete variables that are no longer needed.

--HG--
extra : convert_revision : d95fc7d44909443e1b7952a24ef822ef051c7cf2
2005-03-29 07:55:44 -05:00

471 lines
13 KiB
C++

/*
* Copyright (c) 2004 The Regents of The University of Michigan
* All rights reserved.
*
* 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.
*/
/* @file
* Implements a 8250 UART
*/
#include <string>
#include <vector>
#include "base/inifile.hh"
#include "base/str.hh" // for to_number
#include "base/trace.hh"
#include "dev/simconsole.hh"
#include "dev/uart.hh"
#include "dev/platform.hh"
#include "mem/bus/bus.hh"
#include "mem/bus/pio_interface.hh"
#include "mem/bus/pio_interface_impl.hh"
#include "mem/functional_mem/memory_control.hh"
#include "sim/builder.hh"
using namespace std;
Uart::IntrEvent::IntrEvent(Uart *u, int bit)
: Event(&mainEventQueue), uart(u)
{
DPRINTF(Uart, "UART Interrupt Event Initilizing\n");
intrBit = bit;
}
const char *
Uart::IntrEvent::description()
{
return "uart interrupt delay event";
}
void
Uart::IntrEvent::process()
{
if (intrBit & uart->IER) {
DPRINTF(Uart, "UART InterEvent, interrupting\n");
uart->platform->postConsoleInt();
uart->status |= intrBit;
}
else
DPRINTF(Uart, "UART InterEvent, not interrupting\n");
}
/* The linux serial driver (8250.c about line 1182) loops reading from
* the device until the device reports it has no more data to
* read. After a maximum of 255 iterations the code prints "serial8250
* too much work for irq X," and breaks out of the loop. Since the
* simulated system is so much slower than the actual system, if a
* user is typing on the keyboard it is very easy for them to provide
* input at a fast enough rate to not allow the loop to exit and thus
* the error to be printed. This magic number provides a delay between
* the time the UART receives a character to send to the simulated
* system and the time it actually notifies the system it has a
* character to send to alleviate this problem. --Ali
*/
void
Uart::IntrEvent::scheduleIntr()
{
static const Tick interval = (Tick)((Clock::Float::s / 2e9) * 450);
DPRINTF(Uart, "Scheduling IER interrupt for %#x, at cycle %lld\n", intrBit,
curTick + interval);
if (!scheduled())
schedule(curTick + interval);
else
reschedule(curTick + interval);
}
Uart::Uart(const string &name, SimConsole *c, MemoryController *mmu, Addr a,
Addr s, HierParams *hier, Bus *bus, Tick pio_latency, Platform *p)
: PioDevice(name, p), addr(a), size(s), cons(c),
txIntrEvent(this, TX_INT), rxIntrEvent(this, RX_INT)
{
mmu->add_child(this, RangeSize(addr, size));
if (bus) {
pioInterface = newPioInterface(name, hier, bus, this,
&Uart::cacheAccess);
pioInterface->addAddrRange(RangeSize(addr, size));
pioLatency = pio_latency * bus->clockRatio;
}
readAddr = 0;
IER = 0;
DLAB = 0;
LCR = 0;
MCR = 0;
status = 0;
// set back pointers
cons->uart = this;
platform->uart = this;
}
Fault
Uart::read(MemReqPtr &req, uint8_t *data)
{
Addr daddr = req->paddr - (addr & EV5::PAddrImplMask);
DPRINTF(Uart, " read register %#x\n", daddr);
#ifdef ALPHA_TLASER
switch (req->size) {
case sizeof(uint64_t):
*(uint64_t *)data = 0;
break;
case sizeof(uint32_t):
*(uint32_t *)data = 0;
break;
case sizeof(uint16_t):
*(uint16_t *)data = 0;
break;
case sizeof(uint8_t):
*(uint8_t *)data = 0;
break;
}
switch (daddr) {
case 0x80: // Status Register
if (readAddr == 3) {
readAddr = 0;
if (status & TX_INT)
*data = (1 << 4);
else if (status & RX_INT)
*data = (1 << 5);
else
DPRINTF(Uart, "spurious read\n");
} else {
*data = (1 << 2);
if (status & RX_INT)
*data |= (1 << 0);
}
break;
case 0xc0: // Data register (RX)
if (!cons->dataAvailable())
panic("No data to read");
cons->in(*data);
if (!cons->dataAvailable()) {
platform->clearConsoleInt();
status &= ~RX_INT;
}
DPRINTF(Uart, "read data register \'%c\' %2x\n",
isprint(*data) ? *data : ' ', *data);
break;
}
#else
assert(req->size == 1);
switch (daddr) {
case 0x0:
if (!(LCR & 0x80)) { // read byte
if (cons->dataAvailable())
cons->in(*data);
else {
*(uint8_t*)data = 0;
// A limited amount of these are ok.
DPRINTF(Uart, "empty read of RX register\n");
}
status &= ~RX_INT;
platform->clearConsoleInt();
if (cons->dataAvailable() && (IER & UART_IER_RDI))
rxIntrEvent.scheduleIntr();
} else { // dll divisor latch
;
}
break;
case 0x1:
if (!(LCR & 0x80)) { // Intr Enable Register(IER)
*(uint8_t*)data = IER;
} else { // DLM divisor latch MSB
;
}
break;
case 0x2: // Intr Identification Register (IIR)
DPRINTF(Uart, "IIR Read, status = %#x\n", (uint32_t)status);
if (status)
*(uint8_t*)data = 0;
else
*(uint8_t*)data = 1;
break;
case 0x3: // Line Control Register (LCR)
*(uint8_t*)data = LCR;
break;
case 0x4: // Modem Control Register (MCR)
break;
case 0x5: // Line Status Register (LSR)
uint8_t lsr;
lsr = 0;
// check if there are any bytes to be read
if (cons->dataAvailable())
lsr = UART_LSR_DR;
lsr |= UART_LSR_TEMT | UART_LSR_THRE;
*(uint8_t*)data = lsr;
break;
case 0x6: // Modem Status Register (MSR)
*(uint8_t*)data = 0;
break;
case 0x7: // Scratch Register (SCR)
*(uint8_t*)data = 0; // doesn't exist with at 8250.
break;
default:
panic("Tried to access a UART port that doesn't exist\n");
break;
}
#endif
return No_Fault;
}
Fault
Uart::write(MemReqPtr &req, const uint8_t *data)
{
Addr daddr = req->paddr - (addr & EV5::PAddrImplMask);
DPRINTF(Uart, " write register %#x value %#x\n", daddr, *(uint8_t*)data);
#ifdef ALPHA_TLASER
switch (daddr) {
case 0x80:
readAddr = *data;
switch (*data) {
case 0x28: // Ack of TX
if ((status & TX_INT) == 0)
panic("Ack of transmit, though there was no interrupt");
status &= ~TX_INT;
platform->clearConsoleInt();
break;
case 0x00:
case 0x01:
case 0x03: // going to read RR3
case 0x12:
break;
default:
DPRINTF(Uart, "writing status register %#x \n",
*(uint64_t *)data);
break;
}
break;
case 0xc0: // Data register (TX)
cons->out(*(uint64_t *)data);
platform->postConsoleInt();
status |= TX_INT;
break;
}
#else
switch (daddr) {
case 0x0:
if (!(LCR & 0x80)) { // write byte
cons->out(*(uint8_t *)data);
platform->clearConsoleInt();
status &= ~TX_INT;
if (UART_IER_THRI & IER)
txIntrEvent.scheduleIntr();
} else { // dll divisor latch
;
}
break;
case 0x1:
if (!(LCR & 0x80)) { // Intr Enable Register(IER)
IER = *(uint8_t*)data;
if (UART_IER_THRI & IER)
{
DPRINTF(Uart, "IER: IER_THRI set, scheduling TX intrrupt\n");
txIntrEvent.scheduleIntr();
}
else
{
DPRINTF(Uart, "IER: IER_THRI cleared, descheduling TX intrrupt\n");
if (txIntrEvent.scheduled())
txIntrEvent.deschedule();
if (status & TX_INT)
platform->clearConsoleInt();
status &= ~TX_INT;
}
if ((UART_IER_RDI & IER) && cons->dataAvailable()) {
DPRINTF(Uart, "IER: IER_RDI set, scheduling RX intrrupt\n");
rxIntrEvent.scheduleIntr();
} else {
DPRINTF(Uart, "IER: IER_RDI cleared, descheduling RX intrrupt\n");
if (rxIntrEvent.scheduled())
rxIntrEvent.deschedule();
if (status & RX_INT)
platform->clearConsoleInt();
status &= ~RX_INT;
}
} else { // DLM divisor latch MSB
;
}
break;
case 0x2: // FIFO Control Register (FCR)
break;
case 0x3: // Line Control Register (LCR)
LCR = *(uint8_t*)data;
break;
case 0x4: // Modem Control Register (MCR)
if (*(uint8_t*)data == (UART_MCR_LOOP | 0x0A))
MCR = 0x9A;
break;
case 0x7: // Scratch Register (SCR)
// We are emulating a 8250 so we don't have a scratch reg
break;
default:
panic("Tried to access a UART port that doesn't exist\n");
break;
}
#endif
return No_Fault;
}
void
Uart::dataAvailable()
{
#ifdef ALPHA_TLASER
platform->postConsoleInt();
status |= RX_INT;
#else
// if the kernel wants an interrupt when we have data
if (IER & UART_IER_RDI)
{
platform->postConsoleInt();
status |= RX_INT;
}
#endif
}
Tick
Uart::cacheAccess(MemReqPtr &req)
{
return curTick + pioLatency;
}
void
Uart::serialize(ostream &os)
{
#ifdef ALPHA_TLASER
SERIALIZE_SCALAR(readAddr);
SERIALIZE_SCALAR(status);
#else
SERIALIZE_SCALAR(status);
SERIALIZE_SCALAR(IER);
SERIALIZE_SCALAR(DLAB);
SERIALIZE_SCALAR(LCR);
SERIALIZE_SCALAR(MCR);
Tick rxintrwhen;
if (rxIntrEvent.scheduled())
rxintrwhen = rxIntrEvent.when();
else
rxintrwhen = 0;
Tick txintrwhen;
if (txIntrEvent.scheduled())
txintrwhen = txIntrEvent.when();
else
txintrwhen = 0;
SERIALIZE_SCALAR(rxintrwhen);
SERIALIZE_SCALAR(txintrwhen);
#endif
}
void
Uart::unserialize(Checkpoint *cp, const std::string &section)
{
#ifdef ALPHA_TLASER
UNSERIALIZE_SCALAR(readAddr);
UNSERIALIZE_SCALAR(status);
#else
UNSERIALIZE_SCALAR(status);
UNSERIALIZE_SCALAR(IER);
UNSERIALIZE_SCALAR(DLAB);
UNSERIALIZE_SCALAR(LCR);
UNSERIALIZE_SCALAR(MCR);
Tick rxintrwhen;
Tick txintrwhen;
UNSERIALIZE_SCALAR(rxintrwhen);
UNSERIALIZE_SCALAR(txintrwhen);
if (rxintrwhen != 0)
rxIntrEvent.schedule(rxintrwhen);
if (txintrwhen != 0)
txIntrEvent.schedule(txintrwhen);
#endif
}
BEGIN_DECLARE_SIM_OBJECT_PARAMS(Uart)
SimObjectParam<SimConsole *> console;
SimObjectParam<MemoryController *> mmu;
SimObjectParam<Platform *> platform;
Param<Addr> addr;
Param<Addr> size;
SimObjectParam<Bus*> io_bus;
Param<Tick> pio_latency;
SimObjectParam<HierParams *> hier;
END_DECLARE_SIM_OBJECT_PARAMS(Uart)
BEGIN_INIT_SIM_OBJECT_PARAMS(Uart)
INIT_PARAM(console, "The console"),
INIT_PARAM(mmu, "Memory Controller"),
INIT_PARAM(platform, "Pointer to platfrom"),
INIT_PARAM(addr, "Device Address"),
INIT_PARAM_DFLT(size, "Device size", 0x8),
INIT_PARAM_DFLT(io_bus, "The IO Bus to attach to", NULL),
INIT_PARAM_DFLT(pio_latency, "Programmed IO latency in bus cycles", 1),
INIT_PARAM_DFLT(hier, "Hierarchy global variables", &defaultHierParams)
END_INIT_SIM_OBJECT_PARAMS(Uart)
CREATE_SIM_OBJECT(Uart)
{
return new Uart(getInstanceName(), console, mmu, addr, size, hier, io_bus,
pio_latency, platform);
}
REGISTER_SIM_OBJECT("Uart", Uart)