gem5  v22.1.0.0
lupio_tty.cc
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28 
29 #include "dev/lupio/lupio_tty.hh"
30 
31 #include "base/trace.hh"
32 #include "debug/LupioTTY.hh"
33 #include "dev/platform.hh"
34 #include "mem/packet_access.hh"
35 #include "params/LupioTTY.hh"
36 
37 #define LUPIO_TTY_INVAL 0x80000000
38 
39 /* Same fields for CTRL and STAT registers */
40 #define LUPIO_TTY_WBIT (1 << 0)
41 #define LUPIO_TTY_RBIT (1 << 1)
42 
43 namespace gem5
44 {
45 
46 LupioTTY::LupioTTY(const Params &params)
47  : BasicPioDevice(params, params.pio_size),
48  writChar(-1), readChar(-1), writIntrEn(false), readIntrEn(false),
49  terminal(params.terminal), platform(params.platform)
50 {
51  // setup serial device callbacks
53 }
54 
55 void
57 {
58  unsigned int irq;
59 
60  irq = (writIntrEn && writChar != -1)
61  || (readIntrEn && readChar != -1);
62 
63  if (irq) {
64  DPRINTF(LupioTTY, "LupioTTY InterEvent, interrupting\n");
65  platform->postConsoleInt();
66  } else {
67  DPRINTF(LupioTTY, "LupioTTY InterEvent, not interrupting\n");
68  platform->clearConsoleInt();
69  }
70 }
71 
72 void
74 {
76 
77  // prevent from overwritting an unread character
78  if (readChar != -1) {
79  fprintf(stderr, "Dropping characters\n");
80  } else {
81  // read data from the terminal
84  }
85 }
86 
87 uint64_t
89 {
90  uint32_t ret = LUPIO_TTY_INVAL;
91 
92  switch (addr >> 2) {
93  case LUPIO_TTY_WRIT:
94  DPRINTF(LupioTTY, "Accessing LUPIO_TTY_WRIT\n");
95  if (writChar != -1) {
96  ret = writChar;
97  writChar = -1;
99  }
100  break;
101  case LUPIO_TTY_READ:
102  DPRINTF(LupioTTY, "Accessing LUPIO_TTY_READ\n");
103  if (readChar != -1) {
104  // return new character
105  ret = readChar;
106  readChar = -1;
108  }
109  break;
110  case LUPIO_TTY_CTRL:
111  DPRINTF(LupioTTY, "Accessing LUPIO_TTY_CTRL\n");
112  ret = 0;
113  if (writIntrEn) {
114  ret |= LUPIO_TTY_WBIT;
115  }
116  if (readIntrEn) {
117  ret |= LUPIO_TTY_RBIT;
118  }
119  break;
120  case LUPIO_TTY_STAT:
121  DPRINTF(LupioTTY, "Accessing LUPIO_TTY_STAT\n");
122  // always ready to write
123  ret = LUPIO_TTY_WBIT;
124  // ready to read if unread character available
125  if (readChar != -1) {
126  ret |= LUPIO_TTY_RBIT;
127  }
128  break;
129  default:
130  panic("Unexpected read to the LupioTTY device at address %d!",
131  addr);
132  break;
133  }
134 
135  return ret;
136 }
137 
138 void
139 LupioTTY::lupioTTYWrite(uint8_t addr, uint64_t val64)
140 {
141  uint32_t val = val64;
142  uint8_t c = val;
143 
144  switch (addr >> 2) {
145  case LUPIO_TTY_WRIT:
146  DPRINTF(LupioTTY, "Accessing Write: LUPIO_TTY_WRIT: %d\n", c);
147  // write data to terminal
148  terminal->writeData(c);
149  writChar = c;
151  break;
152  case LUPIO_TTY_CTRL:
153  // set interrupt enable bits
154  DPRINTF(LupioTTY, "Accessing LUPIO_TTY_CTRL\n");
158  break;
159  default:
160  panic("Unexpected write to the LupioTTY device at address %d!",
161  addr);
162  break;
163  }
164 }
165 
166 Tick
168 {
169  Addr tty_addr = pkt->getAddr() - pioAddr;
170 
172  "Read request - addr: %#x, size: %#x\n", tty_addr, pkt->getSize());
173 
174  uint64_t val = lupioTTYRead(tty_addr);
175  pkt->setUintX(val, byteOrder);
176 
177  pkt->makeResponse();
178 
179  return pioDelay;
180 }
181 
182 Tick
184 {
185  Addr tty_addr = pkt->getAddr() - pioAddr;
187  "Write request - addr: %#x pktAddr: %#x value: %c\n", tty_addr,
188  pkt->getAddr(), pkt->getUintX(byteOrder));
189 
190  lupioTTYWrite(tty_addr, pkt->getUintX(byteOrder));
191 
192  pkt->makeResponse();
193 
194  return pioDelay;
195 }
196 
197 } // namespace gem5
#define DPRINTF(x,...)
Definition: trace.hh:186
Addr pioAddr
Address that the device listens to.
Definition: io_device.hh:151
Tick pioDelay
Delay that the device experinces on an access.
Definition: io_device.hh:157
LupioTTY: The LupioTTY is a virtual terminal device that can both transmit characters to a screen,...
Definition: lupio_tty.hh:48
Tick read(PacketPtr pkt) override
Implement BasicPioDevice virtual functions.
Definition: lupio_tty.cc:167
int8_t readChar
Definition: lupio_tty.hh:64
LupioTTY(const Params &p)
Definition: lupio_tty.cc:46
SerialDevice * terminal
Definition: lupio_tty.hh:75
uint64_t lupioTTYRead(const uint8_t addr)
Definition: lupio_tty.cc:88
void dataAvailable()
Inform the LupIO-TTY there is data available.
Definition: lupio_tty.cc:73
const ByteOrder byteOrder
Definition: lupio_tty.hh:76
Platform * platform
Definition: lupio_tty.hh:77
void lupioTTYWrite(const uint8_t addr, uint64_t c)
Definition: lupio_tty.cc:139
int8_t writChar
Definition: lupio_tty.hh:63
Tick write(PacketPtr pkt) override
Pure virtual function that the device must implement.
Definition: lupio_tty.cc:183
void lupioTTYUpdateIRQ()
IRQ management.
Definition: lupio_tty.cc:56
A Packet is used to encapsulate a transfer between two objects in the memory system (e....
Definition: packet.hh:294
Addr getAddr() const
Definition: packet.hh:805
void setUintX(uint64_t w, ByteOrder endian)
Set the value in the word w after truncating it to the length of the packet and then byteswapping it ...
Definition: packet.cc:361
void makeResponse()
Take a request packet and modify it in place to be suitable for returning as a response to that reque...
Definition: packet.hh:1059
unsigned getSize() const
Definition: packet.hh:815
uint64_t getUintX(ByteOrder endian) const
Get the data in the packet byte swapped from the specified endianness and zero-extended to 64 bits.
Definition: packet.cc:352
PioDeviceParams Params
Definition: io_device.hh:134
virtual uint8_t readData()=0
Read a character from the device.
virtual void writeData(uint8_t c)=0
Transmit a character from the host interface to the device.
void regInterfaceCallback(const std::function< void()> &callback)
Register a data available callback into the host interface layer.
Definition: serial.cc:56
virtual bool dataAvailable() const =0
Check if there is pending data from the serial device.
#define panic(...)
This implements a cprintf based panic() function.
Definition: logging.hh:178
#define gem5_assert(cond,...)
The assert macro will function like a normal assert, but will use panic instead of straight abort().
Definition: logging.hh:318
#define LUPIO_TTY_RBIT
Definition: lupio_tty.cc:41
#define LUPIO_TTY_WBIT
Definition: lupio_tty.cc:40
#define LUPIO_TTY_INVAL
Definition: lupio_tty.cc:37
Bitfield< 1 > irq
Definition: misc_types.hh:337
Bitfield< 2 > c
Definition: pagetable.hh:63
Bitfield< 63 > val
Definition: misc.hh:776
Bitfield< 3 > addr
Definition: types.hh:84
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:147
uint64_t Tick
Tick count type.
Definition: types.hh:58
Generic interface for platforms.

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