2 * Exynos4210 UART Emulation
4 * Copyright (C) 2011 Samsung Electronics Co Ltd.
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, see <http://www.gnu.org/licenses/>.
22 #include "hw/sysbus.h"
23 #include "sysemu/sysemu.h"
24 #include "sysemu/char.h"
26 #include "hw/arm/exynos4210.h"
29 #undef DEBUG_UART_EXTEND
35 #define DEBUG_UART_EXTEND 0
37 #define DEBUG_Rx_DATA 0
38 #define DEBUG_Tx_DATA 0
41 #define PRINT_DEBUG(fmt, args...) \
43 fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
47 #define PRINT_DEBUG_EXTEND(fmt, args...) \
49 fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
52 #define PRINT_DEBUG_EXTEND(fmt, args...) \
57 #define PRINT_DEBUG(fmt, args...) \
59 #define PRINT_DEBUG_EXTEND(fmt, args...) \
63 #define PRINT_ERROR(fmt, args...) \
65 fprintf(stderr, " [%s:%d] "fmt, __func__, __LINE__, ##args); \
69 * Offsets for UART registers relative to SFR base address
73 #define ULCON 0x0000 /* Line Control */
74 #define UCON 0x0004 /* Control */
75 #define UFCON 0x0008 /* FIFO Control */
76 #define UMCON 0x000C /* Modem Control */
77 #define UTRSTAT 0x0010 /* Tx/Rx Status */
78 #define UERSTAT 0x0014 /* UART Error Status */
79 #define UFSTAT 0x0018 /* FIFO Status */
80 #define UMSTAT 0x001C /* Modem Status */
81 #define UTXH 0x0020 /* Transmit Buffer */
82 #define URXH 0x0024 /* Receive Buffer */
83 #define UBRDIV 0x0028 /* Baud Rate Divisor */
84 #define UFRACVAL 0x002C /* Divisor Fractional Value */
85 #define UINTP 0x0030 /* Interrupt Pending */
86 #define UINTSP 0x0034 /* Interrupt Source Pending */
87 #define UINTM 0x0038 /* Interrupt Mask */
90 * for indexing register in the uint32_t array
92 * 'reg' - register offset (see offsets definitions above)
95 #define I_(reg) (reg / sizeof(uint32_t))
97 typedef struct Exynos4210UartReg {
98 const char *name; /* the only reason is the debug output */
100 uint32_t reset_value;
103 static Exynos4210UartReg exynos4210_uart_regs[] = {
104 {"ULCON", ULCON, 0x00000000},
105 {"UCON", UCON, 0x00003000},
106 {"UFCON", UFCON, 0x00000000},
107 {"UMCON", UMCON, 0x00000000},
108 {"UTRSTAT", UTRSTAT, 0x00000006}, /* RO */
109 {"UERSTAT", UERSTAT, 0x00000000}, /* RO */
110 {"UFSTAT", UFSTAT, 0x00000000}, /* RO */
111 {"UMSTAT", UMSTAT, 0x00000000}, /* RO */
112 {"UTXH", UTXH, 0x5c5c5c5c}, /* WO, undefined reset value*/
113 {"URXH", URXH, 0x00000000}, /* RO */
114 {"UBRDIV", UBRDIV, 0x00000000},
115 {"UFRACVAL", UFRACVAL, 0x00000000},
116 {"UINTP", UINTP, 0x00000000},
117 {"UINTSP", UINTSP, 0x00000000},
118 {"UINTM", UINTM, 0x00000000},
121 #define EXYNOS4210_UART_REGS_MEM_SIZE 0x3C
123 /* UART FIFO Control */
124 #define UFCON_FIFO_ENABLE 0x1
125 #define UFCON_Rx_FIFO_RESET 0x2
126 #define UFCON_Tx_FIFO_RESET 0x4
127 #define UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT 8
128 #define UFCON_Tx_FIFO_TRIGGER_LEVEL (7 << UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT)
129 #define UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT 4
130 #define UFCON_Rx_FIFO_TRIGGER_LEVEL (7 << UFCON_Rx_FIFO_TRIGGER_LEVEL_SHIFT)
132 /* Uart FIFO Status */
133 #define UFSTAT_Rx_FIFO_COUNT 0xff
134 #define UFSTAT_Rx_FIFO_FULL 0x100
135 #define UFSTAT_Rx_FIFO_ERROR 0x200
136 #define UFSTAT_Tx_FIFO_COUNT_SHIFT 16
137 #define UFSTAT_Tx_FIFO_COUNT (0xff << UFSTAT_Tx_FIFO_COUNT_SHIFT)
138 #define UFSTAT_Tx_FIFO_FULL_SHIFT 24
139 #define UFSTAT_Tx_FIFO_FULL (1 << UFSTAT_Tx_FIFO_FULL_SHIFT)
141 /* UART Interrupt Source Pending */
142 #define UINTSP_RXD 0x1 /* Receive interrupt */
143 #define UINTSP_ERROR 0x2 /* Error interrupt */
144 #define UINTSP_TXD 0x4 /* Transmit interrupt */
145 #define UINTSP_MODEM 0x8 /* Modem interrupt */
147 /* UART Line Control */
148 #define ULCON_IR_MODE_SHIFT 6
149 #define ULCON_PARITY_SHIFT 3
150 #define ULCON_STOP_BIT_SHIFT 1
152 /* UART Tx/Rx Status */
153 #define UTRSTAT_TRANSMITTER_EMPTY 0x4
154 #define UTRSTAT_Tx_BUFFER_EMPTY 0x2
155 #define UTRSTAT_Rx_BUFFER_DATA_READY 0x1
157 /* UART Error Status */
158 #define UERSTAT_OVERRUN 0x1
159 #define UERSTAT_PARITY 0x2
160 #define UERSTAT_FRAME 0x4
161 #define UERSTAT_BREAK 0x8
165 uint32_t sp, rp; /* store and retrieve pointers */
167 } Exynos4210UartFIFO;
169 #define TYPE_EXYNOS4210_UART "exynos4210.uart"
170 #define EXYNOS4210_UART(obj) \
171 OBJECT_CHECK(Exynos4210UartState, (obj), TYPE_EXYNOS4210_UART)
173 typedef struct Exynos4210UartState {
174 SysBusDevice parent_obj;
178 uint32_t reg[EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)];
179 Exynos4210UartFIFO rx;
180 Exynos4210UartFIFO tx;
182 CharDriverState *chr;
187 } Exynos4210UartState;
191 /* Used only for debugging inside PRINT_DEBUG_... macros */
192 static const char *exynos4210_uart_regname(hwaddr offset)
197 for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
198 if (offset == exynos4210_uart_regs[i].offset) {
199 return exynos4210_uart_regs[i].name;
208 static void fifo_store(Exynos4210UartFIFO *q, uint8_t ch)
211 q->sp = (q->sp + 1) % q->size;
214 static uint8_t fifo_retrieve(Exynos4210UartFIFO *q)
216 uint8_t ret = q->data[q->rp];
217 q->rp = (q->rp + 1) % q->size;
221 static int fifo_elements_number(Exynos4210UartFIFO *q)
224 return q->size - q->rp + q->sp;
227 return q->sp - q->rp;
230 static int fifo_empty_elements_number(Exynos4210UartFIFO *q)
232 return q->size - fifo_elements_number(q);
235 static void fifo_reset(Exynos4210UartFIFO *q)
240 q->data = (uint8_t *)g_malloc0(q->size);
246 static uint32_t exynos4210_uart_Tx_FIFO_trigger_level(Exynos4210UartState *s)
251 reg = (s->reg[I_(UFCON)] & UFCON_Tx_FIFO_TRIGGER_LEVEL) >>
252 UFCON_Tx_FIFO_TRIGGER_LEVEL_SHIFT;
254 switch (s->channel) {
268 PRINT_ERROR("Wrong UART channel number: %d\n", s->channel);
274 static void exynos4210_uart_update_irq(Exynos4210UartState *s)
277 * The Tx interrupt is always requested if the number of data in the
278 * transmit FIFO is smaller than the trigger level.
280 if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
282 uint32_t count = (s->reg[I_(UFSTAT)] & UFSTAT_Tx_FIFO_COUNT) >>
283 UFSTAT_Tx_FIFO_COUNT_SHIFT;
285 if (count <= exynos4210_uart_Tx_FIFO_trigger_level(s)) {
286 s->reg[I_(UINTSP)] |= UINTSP_TXD;
290 s->reg[I_(UINTP)] = s->reg[I_(UINTSP)] & ~s->reg[I_(UINTM)];
292 if (s->reg[I_(UINTP)]) {
293 qemu_irq_raise(s->irq);
296 fprintf(stderr, "UART%d: IRQ has been raised: %08x\n",
297 s->channel, s->reg[I_(UINTP)]);
301 qemu_irq_lower(s->irq);
305 static void exynos4210_uart_update_parameters(Exynos4210UartState *s)
307 int speed, parity, data_bits, stop_bits, frame_size;
308 QEMUSerialSetParams ssp;
311 if (s->reg[I_(UBRDIV)] == 0) {
315 frame_size = 1; /* start bit */
316 if (s->reg[I_(ULCON)] & 0x20) {
317 frame_size++; /* parity bit */
318 if (s->reg[I_(ULCON)] & 0x28) {
327 if (s->reg[I_(ULCON)] & 0x4) {
333 data_bits = (s->reg[I_(ULCON)] & 0x3) + 5;
335 frame_size += data_bits + stop_bits;
337 uclk_rate = 24000000;
339 speed = uclk_rate / ((16 * (s->reg[I_(UBRDIV)]) & 0xffff) +
340 (s->reg[I_(UFRACVAL)] & 0x7) + 16);
344 ssp.data_bits = data_bits;
345 ssp.stop_bits = stop_bits;
347 qemu_chr_fe_ioctl(s->chr, CHR_IOCTL_SERIAL_SET_PARAMS, &ssp);
349 PRINT_DEBUG("UART%d: speed: %d, parity: %c, data: %d, stop: %d\n",
350 s->channel, speed, parity, data_bits, stop_bits);
353 static void exynos4210_uart_write(void *opaque, hwaddr offset,
354 uint64_t val, unsigned size)
356 Exynos4210UartState *s = (Exynos4210UartState *)opaque;
359 PRINT_DEBUG_EXTEND("UART%d: <0x%04x> %s <- 0x%08llx\n", s->channel,
360 offset, exynos4210_uart_regname(offset), (long long unsigned int)val);
366 s->reg[I_(offset)] = val;
367 exynos4210_uart_update_parameters(s);
370 s->reg[I_(UFCON)] = val;
371 if (val & UFCON_Rx_FIFO_RESET) {
373 s->reg[I_(UFCON)] &= ~UFCON_Rx_FIFO_RESET;
374 PRINT_DEBUG("UART%d: Rx FIFO Reset\n", s->channel);
376 if (val & UFCON_Tx_FIFO_RESET) {
378 s->reg[I_(UFCON)] &= ~UFCON_Tx_FIFO_RESET;
379 PRINT_DEBUG("UART%d: Tx FIFO Reset\n", s->channel);
385 s->reg[I_(UTRSTAT)] &= ~(UTRSTAT_TRANSMITTER_EMPTY |
386 UTRSTAT_Tx_BUFFER_EMPTY);
388 qemu_chr_fe_write(s->chr, &ch, 1);
390 fprintf(stderr, "%c", ch);
392 s->reg[I_(UTRSTAT)] |= UTRSTAT_TRANSMITTER_EMPTY |
393 UTRSTAT_Tx_BUFFER_EMPTY;
394 s->reg[I_(UINTSP)] |= UINTSP_TXD;
395 exynos4210_uart_update_irq(s);
400 s->reg[I_(UINTP)] &= ~val;
401 s->reg[I_(UINTSP)] &= ~val;
402 PRINT_DEBUG("UART%d: UINTP [%04x] have been cleared: %08x\n",
403 s->channel, offset, s->reg[I_(UINTP)]);
404 exynos4210_uart_update_irq(s);
411 PRINT_DEBUG("UART%d: Trying to write into RO register: %s [%04x]\n",
412 s->channel, exynos4210_uart_regname(offset), offset);
415 s->reg[I_(UINTSP)] &= ~val;
418 s->reg[I_(UINTM)] = val;
419 exynos4210_uart_update_irq(s);
424 s->reg[I_(offset)] = val;
428 static uint64_t exynos4210_uart_read(void *opaque, hwaddr offset,
431 Exynos4210UartState *s = (Exynos4210UartState *)opaque;
435 case UERSTAT: /* Read Only */
436 res = s->reg[I_(UERSTAT)];
437 s->reg[I_(UERSTAT)] = 0;
439 case UFSTAT: /* Read Only */
440 s->reg[I_(UFSTAT)] = fifo_elements_number(&s->rx) & 0xff;
441 if (fifo_empty_elements_number(&s->rx) == 0) {
442 s->reg[I_(UFSTAT)] |= UFSTAT_Rx_FIFO_FULL;
443 s->reg[I_(UFSTAT)] &= ~0xff;
445 return s->reg[I_(UFSTAT)];
447 if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
448 if (fifo_elements_number(&s->rx)) {
449 res = fifo_retrieve(&s->rx);
451 fprintf(stderr, "%c", res);
453 if (!fifo_elements_number(&s->rx)) {
454 s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
456 s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
459 s->reg[I_(UINTSP)] |= UINTSP_ERROR;
460 exynos4210_uart_update_irq(s);
464 s->reg[I_(UTRSTAT)] &= ~UTRSTAT_Rx_BUFFER_DATA_READY;
465 res = s->reg[I_(URXH)];
469 PRINT_DEBUG("UART%d: Trying to read from WO register: %s [%04x]\n",
470 s->channel, exynos4210_uart_regname(offset), offset);
473 return s->reg[I_(offset)];
479 static const MemoryRegionOps exynos4210_uart_ops = {
480 .read = exynos4210_uart_read,
481 .write = exynos4210_uart_write,
482 .endianness = DEVICE_NATIVE_ENDIAN,
484 .max_access_size = 4,
489 static int exynos4210_uart_can_receive(void *opaque)
491 Exynos4210UartState *s = (Exynos4210UartState *)opaque;
493 return fifo_empty_elements_number(&s->rx);
497 static void exynos4210_uart_receive(void *opaque, const uint8_t *buf, int size)
499 Exynos4210UartState *s = (Exynos4210UartState *)opaque;
502 if (s->reg[I_(UFCON)] & UFCON_FIFO_ENABLE) {
503 if (fifo_empty_elements_number(&s->rx) < size) {
504 for (i = 0; i < fifo_empty_elements_number(&s->rx); i++) {
505 fifo_store(&s->rx, buf[i]);
507 s->reg[I_(UINTSP)] |= UINTSP_ERROR;
508 s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
510 for (i = 0; i < size; i++) {
511 fifo_store(&s->rx, buf[i]);
513 s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
515 /* XXX: Around here we maybe should check Rx trigger level */
516 s->reg[I_(UINTSP)] |= UINTSP_RXD;
518 s->reg[I_(URXH)] = buf[0];
519 s->reg[I_(UINTSP)] |= UINTSP_RXD;
520 s->reg[I_(UTRSTAT)] |= UTRSTAT_Rx_BUFFER_DATA_READY;
523 exynos4210_uart_update_irq(s);
527 static void exynos4210_uart_event(void *opaque, int event)
529 Exynos4210UartState *s = (Exynos4210UartState *)opaque;
531 if (event == CHR_EVENT_BREAK) {
532 /* When the RxDn is held in logic 0, then a null byte is pushed into the
534 fifo_store(&s->rx, '\0');
535 s->reg[I_(UERSTAT)] |= UERSTAT_BREAK;
536 exynos4210_uart_update_irq(s);
541 static void exynos4210_uart_reset(DeviceState *dev)
543 Exynos4210UartState *s = EXYNOS4210_UART(dev);
546 for (i = 0; i < ARRAY_SIZE(exynos4210_uart_regs); i++) {
547 s->reg[I_(exynos4210_uart_regs[i].offset)] =
548 exynos4210_uart_regs[i].reset_value;
554 PRINT_DEBUG("UART%d: Rx FIFO size: %d\n", s->channel, s->rx.size);
557 static const VMStateDescription vmstate_exynos4210_uart_fifo = {
558 .name = "exynos4210.uart.fifo",
560 .minimum_version_id = 1,
561 .fields = (VMStateField[]) {
562 VMSTATE_UINT32(sp, Exynos4210UartFIFO),
563 VMSTATE_UINT32(rp, Exynos4210UartFIFO),
564 VMSTATE_VBUFFER_UINT32(data, Exynos4210UartFIFO, 1, NULL, 0, size),
565 VMSTATE_END_OF_LIST()
569 static const VMStateDescription vmstate_exynos4210_uart = {
570 .name = "exynos4210.uart",
572 .minimum_version_id = 1,
573 .fields = (VMStateField[]) {
574 VMSTATE_STRUCT(rx, Exynos4210UartState, 1,
575 vmstate_exynos4210_uart_fifo, Exynos4210UartFIFO),
576 VMSTATE_UINT32_ARRAY(reg, Exynos4210UartState,
577 EXYNOS4210_UART_REGS_MEM_SIZE / sizeof(uint32_t)),
578 VMSTATE_END_OF_LIST()
582 DeviceState *exynos4210_uart_create(hwaddr addr,
585 CharDriverState *chr,
591 const char chr_name[] = "serial";
592 char label[ARRAY_SIZE(chr_name) + 1];
594 dev = qdev_create(NULL, TYPE_EXYNOS4210_UART);
597 if (channel >= MAX_SERIAL_PORTS) {
598 hw_error("Only %d serial ports are supported by QEMU.\n",
601 chr = serial_hds[channel];
603 snprintf(label, ARRAY_SIZE(label), "%s%d", chr_name, channel);
604 chr = qemu_chr_new(label, "null", NULL);
606 hw_error("Can't assign serial port to UART%d.\n", channel);
611 qdev_prop_set_chr(dev, "chardev", chr);
612 qdev_prop_set_uint32(dev, "channel", channel);
613 qdev_prop_set_uint32(dev, "rx-size", fifo_size);
614 qdev_prop_set_uint32(dev, "tx-size", fifo_size);
616 bus = SYS_BUS_DEVICE(dev);
617 qdev_init_nofail(dev);
618 if (addr != (hwaddr)-1) {
619 sysbus_mmio_map(bus, 0, addr);
621 sysbus_connect_irq(bus, 0, irq);
626 static int exynos4210_uart_init(SysBusDevice *dev)
628 Exynos4210UartState *s = EXYNOS4210_UART(dev);
631 memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_uart_ops, s,
632 "exynos4210.uart", EXYNOS4210_UART_REGS_MEM_SIZE);
633 sysbus_init_mmio(dev, &s->iomem);
635 sysbus_init_irq(dev, &s->irq);
637 qemu_chr_add_handlers(s->chr, exynos4210_uart_can_receive,
638 exynos4210_uart_receive, exynos4210_uart_event, s);
643 static Property exynos4210_uart_properties[] = {
644 DEFINE_PROP_CHR("chardev", Exynos4210UartState, chr),
645 DEFINE_PROP_UINT32("channel", Exynos4210UartState, channel, 0),
646 DEFINE_PROP_UINT32("rx-size", Exynos4210UartState, rx.size, 16),
647 DEFINE_PROP_UINT32("tx-size", Exynos4210UartState, tx.size, 16),
648 DEFINE_PROP_END_OF_LIST(),
651 static void exynos4210_uart_class_init(ObjectClass *klass, void *data)
653 DeviceClass *dc = DEVICE_CLASS(klass);
654 SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
656 k->init = exynos4210_uart_init;
657 dc->reset = exynos4210_uart_reset;
658 dc->props = exynos4210_uart_properties;
659 dc->vmsd = &vmstate_exynos4210_uart;
662 static const TypeInfo exynos4210_uart_info = {
663 .name = TYPE_EXYNOS4210_UART,
664 .parent = TYPE_SYS_BUS_DEVICE,
665 .instance_size = sizeof(Exynos4210UartState),
666 .class_init = exynos4210_uart_class_init,
669 static void exynos4210_uart_register(void)
671 type_register_static(&exynos4210_uart_info);
674 type_init(exynos4210_uart_register)