xref: /qemu/hw/char/ibex_uart.c (revision bdc36ce649e2985225fcf9ab4958698fcafb04e9)
1a7d2d98cSAlistair Francis /*
2a7d2d98cSAlistair Francis  * QEMU lowRISC Ibex UART device
3a7d2d98cSAlistair Francis  *
4a7d2d98cSAlistair Francis  * Copyright (c) 2020 Western Digital
5a7d2d98cSAlistair Francis  *
6a7d2d98cSAlistair Francis  * For details check the documentation here:
7a7d2d98cSAlistair Francis  *    https://docs.opentitan.org/hw/ip/uart/doc/
8a7d2d98cSAlistair Francis  *
9a7d2d98cSAlistair Francis  * Permission is hereby granted, free of charge, to any person obtaining a copy
10a7d2d98cSAlistair Francis  * of this software and associated documentation files (the "Software"), to deal
11a7d2d98cSAlistair Francis  * in the Software without restriction, including without limitation the rights
12a7d2d98cSAlistair Francis  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13a7d2d98cSAlistair Francis  * copies of the Software, and to permit persons to whom the Software is
14a7d2d98cSAlistair Francis  * furnished to do so, subject to the following conditions:
15a7d2d98cSAlistair Francis  *
16a7d2d98cSAlistair Francis  * The above copyright notice and this permission notice shall be included in
17a7d2d98cSAlistair Francis  * all copies or substantial portions of the Software.
18a7d2d98cSAlistair Francis  *
19a7d2d98cSAlistair Francis  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20a7d2d98cSAlistair Francis  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21a7d2d98cSAlistair Francis  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22a7d2d98cSAlistair Francis  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23a7d2d98cSAlistair Francis  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24a7d2d98cSAlistair Francis  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25a7d2d98cSAlistair Francis  * THE SOFTWARE.
26a7d2d98cSAlistair Francis  */
27a7d2d98cSAlistair Francis 
28a7d2d98cSAlistair Francis #include "qemu/osdep.h"
29a7d2d98cSAlistair Francis #include "hw/char/ibex_uart.h"
30a7d2d98cSAlistair Francis #include "hw/irq.h"
31940aabb9SAlistair Francis #include "hw/qdev-clock.h"
32a7d2d98cSAlistair Francis #include "hw/qdev-properties.h"
33ce35e229SEduardo Habkost #include "hw/qdev-properties-system.h"
34a7d2d98cSAlistair Francis #include "migration/vmstate.h"
35a7d2d98cSAlistair Francis #include "qemu/log.h"
36a7d2d98cSAlistair Francis #include "qemu/module.h"
37a7d2d98cSAlistair Francis 
38*bdc36ce6SAlistair Francis REG32(INTR_STATE, 0x00)
39*bdc36ce6SAlistair Francis     FIELD(INTR_STATE, TX_WATERMARK, 0, 1)
40*bdc36ce6SAlistair Francis     FIELD(INTR_STATE, RX_WATERMARK, 1, 1)
41*bdc36ce6SAlistair Francis     FIELD(INTR_STATE, TX_EMPTY, 2, 1)
42*bdc36ce6SAlistair Francis     FIELD(INTR_STATE, RX_OVERFLOW, 3, 1)
43*bdc36ce6SAlistair Francis REG32(INTR_ENABLE, 0x04)
44*bdc36ce6SAlistair Francis REG32(INTR_TEST, 0x08)
45*bdc36ce6SAlistair Francis REG32(CTRL, 0x0C)
46*bdc36ce6SAlistair Francis     FIELD(CTRL, TX_ENABLE, 0, 1)
47*bdc36ce6SAlistair Francis     FIELD(CTRL, RX_ENABLE, 1, 1)
48*bdc36ce6SAlistair Francis     FIELD(CTRL, NF, 2, 1)
49*bdc36ce6SAlistair Francis     FIELD(CTRL, SLPBK, 4, 1)
50*bdc36ce6SAlistair Francis     FIELD(CTRL, LLPBK, 5, 1)
51*bdc36ce6SAlistair Francis     FIELD(CTRL, PARITY_EN, 6, 1)
52*bdc36ce6SAlistair Francis     FIELD(CTRL, PARITY_ODD, 7, 1)
53*bdc36ce6SAlistair Francis     FIELD(CTRL, RXBLVL, 8, 2)
54*bdc36ce6SAlistair Francis     FIELD(CTRL, NCO, 16, 16)
55*bdc36ce6SAlistair Francis REG32(STATUS, 0x10)
56*bdc36ce6SAlistair Francis     FIELD(STATUS, TXFULL, 0, 1)
57*bdc36ce6SAlistair Francis     FIELD(STATUS, RXFULL, 1, 1)
58*bdc36ce6SAlistair Francis     FIELD(STATUS, TXEMPTY, 2, 1)
59*bdc36ce6SAlistair Francis     FIELD(STATUS, RXIDLE, 4, 1)
60*bdc36ce6SAlistair Francis     FIELD(STATUS, RXEMPTY, 5, 1)
61*bdc36ce6SAlistair Francis REG32(RDATA, 0x14)
62*bdc36ce6SAlistair Francis REG32(WDATA, 0x18)
63*bdc36ce6SAlistair Francis REG32(FIFO_CTRL, 0x1c)
64*bdc36ce6SAlistair Francis     FIELD(FIFO_CTRL, RXRST, 0, 1)
65*bdc36ce6SAlistair Francis     FIELD(FIFO_CTRL, TXRST, 1, 1)
66*bdc36ce6SAlistair Francis     FIELD(FIFO_CTRL, RXILVL, 2, 3)
67*bdc36ce6SAlistair Francis     FIELD(FIFO_CTRL, TXILVL, 5, 2)
68*bdc36ce6SAlistair Francis REG32(FIFO_STATUS, 0x20)
69*bdc36ce6SAlistair Francis     FIELD(FIFO_STATUS, TXLVL, 0, 5)
70*bdc36ce6SAlistair Francis     FIELD(FIFO_STATUS, RXLVL, 16, 5)
71*bdc36ce6SAlistair Francis REG32(OVRD, 0x24)
72*bdc36ce6SAlistair Francis REG32(VAL, 0x28)
73*bdc36ce6SAlistair Francis REG32(TIMEOUT_CTRL, 0x2c)
74*bdc36ce6SAlistair Francis 
75a7d2d98cSAlistair Francis static void ibex_uart_update_irqs(IbexUartState *s)
76a7d2d98cSAlistair Francis {
7759093cc4SAlistair Francis     if (s->uart_intr_state & s->uart_intr_enable & R_INTR_STATE_TX_WATERMARK_MASK) {
78a7d2d98cSAlistair Francis         qemu_set_irq(s->tx_watermark, 1);
79a7d2d98cSAlistair Francis     } else {
80a7d2d98cSAlistair Francis         qemu_set_irq(s->tx_watermark, 0);
81a7d2d98cSAlistair Francis     }
82a7d2d98cSAlistair Francis 
8359093cc4SAlistair Francis     if (s->uart_intr_state & s->uart_intr_enable & R_INTR_STATE_RX_WATERMARK_MASK) {
84a7d2d98cSAlistair Francis         qemu_set_irq(s->rx_watermark, 1);
85a7d2d98cSAlistair Francis     } else {
86a7d2d98cSAlistair Francis         qemu_set_irq(s->rx_watermark, 0);
87a7d2d98cSAlistair Francis     }
88a7d2d98cSAlistair Francis 
8959093cc4SAlistair Francis     if (s->uart_intr_state & s->uart_intr_enable & R_INTR_STATE_TX_EMPTY_MASK) {
90a7d2d98cSAlistair Francis         qemu_set_irq(s->tx_empty, 1);
91a7d2d98cSAlistair Francis     } else {
92a7d2d98cSAlistair Francis         qemu_set_irq(s->tx_empty, 0);
93a7d2d98cSAlistair Francis     }
94a7d2d98cSAlistair Francis 
9559093cc4SAlistair Francis     if (s->uart_intr_state & s->uart_intr_enable & R_INTR_STATE_RX_OVERFLOW_MASK) {
96a7d2d98cSAlistair Francis         qemu_set_irq(s->rx_overflow, 1);
97a7d2d98cSAlistair Francis     } else {
98a7d2d98cSAlistair Francis         qemu_set_irq(s->rx_overflow, 0);
99a7d2d98cSAlistair Francis     }
100a7d2d98cSAlistair Francis }
101a7d2d98cSAlistair Francis 
102a7d2d98cSAlistair Francis static int ibex_uart_can_receive(void *opaque)
103a7d2d98cSAlistair Francis {
104a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
105a7d2d98cSAlistair Francis 
10682a4ed8eSAlexander Wagner     if ((s->uart_ctrl & R_CTRL_RX_ENABLE_MASK)
10782a4ed8eSAlexander Wagner            && !(s->uart_status & R_STATUS_RXFULL_MASK)) {
108a7d2d98cSAlistair Francis         return 1;
109a7d2d98cSAlistair Francis     }
110a7d2d98cSAlistair Francis 
111a7d2d98cSAlistair Francis     return 0;
112a7d2d98cSAlistair Francis }
113a7d2d98cSAlistair Francis 
114a7d2d98cSAlistair Francis static void ibex_uart_receive(void *opaque, const uint8_t *buf, int size)
115a7d2d98cSAlistair Francis {
116a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
11759093cc4SAlistair Francis     uint8_t rx_fifo_level = (s->uart_fifo_ctrl & R_FIFO_CTRL_RXILVL_MASK)
11859093cc4SAlistair Francis                             >> R_FIFO_CTRL_RXILVL_SHIFT;
119a7d2d98cSAlistair Francis 
120a7d2d98cSAlistair Francis     s->uart_rdata = *buf;
121a7d2d98cSAlistair Francis 
12259093cc4SAlistair Francis     s->uart_status &= ~R_STATUS_RXIDLE_MASK;
12359093cc4SAlistair Francis     s->uart_status &= ~R_STATUS_RXEMPTY_MASK;
12482a4ed8eSAlexander Wagner     /* The RXFULL is set after receiving a single byte
12582a4ed8eSAlexander Wagner      * as the FIFO buffers are not yet implemented.
12682a4ed8eSAlexander Wagner      */
12782a4ed8eSAlexander Wagner     s->uart_status |= R_STATUS_RXFULL_MASK;
12882a4ed8eSAlexander Wagner     s->rx_level += 1;
129a7d2d98cSAlistair Francis 
130a7d2d98cSAlistair Francis     if (size > rx_fifo_level) {
13159093cc4SAlistair Francis         s->uart_intr_state |= R_INTR_STATE_RX_WATERMARK_MASK;
132a7d2d98cSAlistair Francis     }
133a7d2d98cSAlistair Francis 
134a7d2d98cSAlistair Francis     ibex_uart_update_irqs(s);
135a7d2d98cSAlistair Francis }
136a7d2d98cSAlistair Francis 
137a7d2d98cSAlistair Francis static gboolean ibex_uart_xmit(GIOChannel *chan, GIOCondition cond,
138a7d2d98cSAlistair Francis                                void *opaque)
139a7d2d98cSAlistair Francis {
140a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
14159093cc4SAlistair Francis     uint8_t tx_fifo_level = (s->uart_fifo_ctrl & R_FIFO_CTRL_TXILVL_MASK)
14259093cc4SAlistair Francis                             >> R_FIFO_CTRL_TXILVL_SHIFT;
143a7d2d98cSAlistair Francis     int ret;
144a7d2d98cSAlistair Francis 
145a7d2d98cSAlistair Francis     /* instant drain the fifo when there's no back-end */
146a7d2d98cSAlistair Francis     if (!qemu_chr_fe_backend_connected(&s->chr)) {
147a7d2d98cSAlistair Francis         s->tx_level = 0;
148a7d2d98cSAlistair Francis         return FALSE;
149a7d2d98cSAlistair Francis     }
150a7d2d98cSAlistair Francis 
151a7d2d98cSAlistair Francis     if (!s->tx_level) {
15259093cc4SAlistair Francis         s->uart_status &= ~R_STATUS_TXFULL_MASK;
15359093cc4SAlistair Francis         s->uart_status |= R_STATUS_TXEMPTY_MASK;
15459093cc4SAlistair Francis         s->uart_intr_state |= R_INTR_STATE_TX_EMPTY_MASK;
15559093cc4SAlistair Francis         s->uart_intr_state &= ~R_INTR_STATE_TX_WATERMARK_MASK;
156a7d2d98cSAlistair Francis         ibex_uart_update_irqs(s);
157a7d2d98cSAlistair Francis         return FALSE;
158a7d2d98cSAlistair Francis     }
159a7d2d98cSAlistair Francis 
160a7d2d98cSAlistair Francis     ret = qemu_chr_fe_write(&s->chr, s->tx_fifo, s->tx_level);
161a7d2d98cSAlistair Francis 
162a7d2d98cSAlistair Francis     if (ret >= 0) {
163a7d2d98cSAlistair Francis         s->tx_level -= ret;
164a7d2d98cSAlistair Francis         memmove(s->tx_fifo, s->tx_fifo + ret, s->tx_level);
165a7d2d98cSAlistair Francis     }
166a7d2d98cSAlistair Francis 
167a7d2d98cSAlistair Francis     if (s->tx_level) {
168a7d2d98cSAlistair Francis         guint r = qemu_chr_fe_add_watch(&s->chr, G_IO_OUT | G_IO_HUP,
169a7d2d98cSAlistair Francis                                         ibex_uart_xmit, s);
170a7d2d98cSAlistair Francis         if (!r) {
171a7d2d98cSAlistair Francis             s->tx_level = 0;
172a7d2d98cSAlistair Francis             return FALSE;
173a7d2d98cSAlistair Francis         }
174a7d2d98cSAlistair Francis     }
175a7d2d98cSAlistair Francis 
176a7d2d98cSAlistair Francis     /* Clear the TX Full bit */
177a7d2d98cSAlistair Francis     if (s->tx_level != IBEX_UART_TX_FIFO_SIZE) {
17859093cc4SAlistair Francis         s->uart_status &= ~R_STATUS_TXFULL_MASK;
179a7d2d98cSAlistair Francis     }
180a7d2d98cSAlistair Francis 
181a7d2d98cSAlistair Francis     /* Disable the TX_WATERMARK IRQ */
182a7d2d98cSAlistair Francis     if (s->tx_level < tx_fifo_level) {
18359093cc4SAlistair Francis         s->uart_intr_state &= ~R_INTR_STATE_TX_WATERMARK_MASK;
184a7d2d98cSAlistair Francis     }
185a7d2d98cSAlistair Francis 
186a7d2d98cSAlistair Francis     /* Set TX empty */
187a7d2d98cSAlistair Francis     if (s->tx_level == 0) {
18859093cc4SAlistair Francis         s->uart_status |= R_STATUS_TXEMPTY_MASK;
18959093cc4SAlistair Francis         s->uart_intr_state |= R_INTR_STATE_TX_EMPTY_MASK;
190a7d2d98cSAlistair Francis     }
191a7d2d98cSAlistair Francis 
192a7d2d98cSAlistair Francis     ibex_uart_update_irqs(s);
193a7d2d98cSAlistair Francis     return FALSE;
194a7d2d98cSAlistair Francis }
195a7d2d98cSAlistair Francis 
196a7d2d98cSAlistair Francis static void uart_write_tx_fifo(IbexUartState *s, const uint8_t *buf,
197a7d2d98cSAlistair Francis                                int size)
198a7d2d98cSAlistair Francis {
199a7d2d98cSAlistair Francis     uint64_t current_time = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
20059093cc4SAlistair Francis     uint8_t tx_fifo_level = (s->uart_fifo_ctrl & R_FIFO_CTRL_TXILVL_MASK)
20159093cc4SAlistair Francis                             >> R_FIFO_CTRL_TXILVL_SHIFT;
202a7d2d98cSAlistair Francis 
203a7d2d98cSAlistair Francis     if (size > IBEX_UART_TX_FIFO_SIZE - s->tx_level) {
204a7d2d98cSAlistair Francis         size = IBEX_UART_TX_FIFO_SIZE - s->tx_level;
205a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR, "ibex_uart: TX FIFO overflow");
206a7d2d98cSAlistair Francis     }
207a7d2d98cSAlistair Francis 
208a7d2d98cSAlistair Francis     memcpy(s->tx_fifo + s->tx_level, buf, size);
209a7d2d98cSAlistair Francis     s->tx_level += size;
210a7d2d98cSAlistair Francis 
211a7d2d98cSAlistair Francis     if (s->tx_level > 0) {
21259093cc4SAlistair Francis         s->uart_status &= ~R_STATUS_TXEMPTY_MASK;
213a7d2d98cSAlistair Francis     }
214a7d2d98cSAlistair Francis 
215a7d2d98cSAlistair Francis     if (s->tx_level >= tx_fifo_level) {
21659093cc4SAlistair Francis         s->uart_intr_state |= R_INTR_STATE_TX_WATERMARK_MASK;
217a7d2d98cSAlistair Francis         ibex_uart_update_irqs(s);
218a7d2d98cSAlistair Francis     }
219a7d2d98cSAlistair Francis 
220a7d2d98cSAlistair Francis     if (s->tx_level == IBEX_UART_TX_FIFO_SIZE) {
22159093cc4SAlistair Francis         s->uart_status |= R_STATUS_TXFULL_MASK;
222a7d2d98cSAlistair Francis     }
223a7d2d98cSAlistair Francis 
224a7d2d98cSAlistair Francis     timer_mod(s->fifo_trigger_handle, current_time +
225a7d2d98cSAlistair Francis               (s->char_tx_time * 4));
226a7d2d98cSAlistair Francis }
227a7d2d98cSAlistair Francis 
228a7d2d98cSAlistair Francis static void ibex_uart_reset(DeviceState *dev)
229a7d2d98cSAlistair Francis {
230a7d2d98cSAlistair Francis     IbexUartState *s = IBEX_UART(dev);
231a7d2d98cSAlistair Francis 
232a7d2d98cSAlistair Francis     s->uart_intr_state = 0x00000000;
233a7d2d98cSAlistair Francis     s->uart_intr_state = 0x00000000;
234a7d2d98cSAlistair Francis     s->uart_intr_enable = 0x00000000;
235a7d2d98cSAlistair Francis     s->uart_ctrl = 0x00000000;
236a7d2d98cSAlistair Francis     s->uart_status = 0x0000003c;
237a7d2d98cSAlistair Francis     s->uart_rdata = 0x00000000;
238a7d2d98cSAlistair Francis     s->uart_fifo_ctrl = 0x00000000;
239a7d2d98cSAlistair Francis     s->uart_fifo_status = 0x00000000;
240a7d2d98cSAlistair Francis     s->uart_ovrd = 0x00000000;
241a7d2d98cSAlistair Francis     s->uart_val = 0x00000000;
242a7d2d98cSAlistair Francis     s->uart_timeout_ctrl = 0x00000000;
243a7d2d98cSAlistair Francis 
244a7d2d98cSAlistair Francis     s->tx_level = 0;
24582a4ed8eSAlexander Wagner     s->rx_level = 0;
246a7d2d98cSAlistair Francis 
247a7d2d98cSAlistair Francis     s->char_tx_time = (NANOSECONDS_PER_SECOND / 230400) * 10;
248a7d2d98cSAlistair Francis 
249a7d2d98cSAlistair Francis     ibex_uart_update_irqs(s);
250a7d2d98cSAlistair Francis }
251a7d2d98cSAlistair Francis 
252940aabb9SAlistair Francis static uint64_t ibex_uart_get_baud(IbexUartState *s)
253940aabb9SAlistair Francis {
254940aabb9SAlistair Francis     uint64_t baud;
255940aabb9SAlistair Francis 
25659093cc4SAlistair Francis     baud = ((s->uart_ctrl & R_CTRL_NCO_MASK) >> 16);
257940aabb9SAlistair Francis     baud *= clock_get_hz(s->f_clk);
258940aabb9SAlistair Francis     baud >>= 20;
259940aabb9SAlistair Francis 
260940aabb9SAlistair Francis     return baud;
261940aabb9SAlistair Francis }
262940aabb9SAlistair Francis 
263a7d2d98cSAlistair Francis static uint64_t ibex_uart_read(void *opaque, hwaddr addr,
264a7d2d98cSAlistair Francis                                        unsigned int size)
265a7d2d98cSAlistair Francis {
266a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
267a7d2d98cSAlistair Francis     uint64_t retvalue = 0;
268a7d2d98cSAlistair Francis 
26959093cc4SAlistair Francis     switch (addr >> 2) {
27059093cc4SAlistair Francis     case R_INTR_STATE:
271a7d2d98cSAlistair Francis         retvalue = s->uart_intr_state;
272a7d2d98cSAlistair Francis         break;
27359093cc4SAlistair Francis     case R_INTR_ENABLE:
274a7d2d98cSAlistair Francis         retvalue = s->uart_intr_enable;
275a7d2d98cSAlistair Francis         break;
27659093cc4SAlistair Francis     case R_INTR_TEST:
277a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
278a7d2d98cSAlistair Francis                       "%s: wdata is write only\n", __func__);
279a7d2d98cSAlistair Francis         break;
280a7d2d98cSAlistair Francis 
28159093cc4SAlistair Francis     case R_CTRL:
282a7d2d98cSAlistair Francis         retvalue = s->uart_ctrl;
283a7d2d98cSAlistair Francis         break;
28459093cc4SAlistair Francis     case R_STATUS:
285a7d2d98cSAlistair Francis         retvalue = s->uart_status;
286a7d2d98cSAlistair Francis         break;
287a7d2d98cSAlistair Francis 
28859093cc4SAlistair Francis     case R_RDATA:
289a7d2d98cSAlistair Francis         retvalue = s->uart_rdata;
29082a4ed8eSAlexander Wagner         if ((s->uart_ctrl & R_CTRL_RX_ENABLE_MASK) && (s->rx_level > 0)) {
291a7d2d98cSAlistair Francis             qemu_chr_fe_accept_input(&s->chr);
292a7d2d98cSAlistair Francis 
29382a4ed8eSAlexander Wagner             s->rx_level -= 1;
29482a4ed8eSAlexander Wagner             s->uart_status &= ~R_STATUS_RXFULL_MASK;
29582a4ed8eSAlexander Wagner             if (s->rx_level == 0) {
29659093cc4SAlistair Francis                 s->uart_status |= R_STATUS_RXIDLE_MASK;
29759093cc4SAlistair Francis                 s->uart_status |= R_STATUS_RXEMPTY_MASK;
298a7d2d98cSAlistair Francis             }
29982a4ed8eSAlexander Wagner         }
300a7d2d98cSAlistair Francis         break;
30159093cc4SAlistair Francis     case R_WDATA:
302a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
303a7d2d98cSAlistair Francis                       "%s: wdata is write only\n", __func__);
304a7d2d98cSAlistair Francis         break;
305a7d2d98cSAlistair Francis 
30659093cc4SAlistair Francis     case R_FIFO_CTRL:
307a7d2d98cSAlistair Francis         retvalue = s->uart_fifo_ctrl;
308a7d2d98cSAlistair Francis         break;
30959093cc4SAlistair Francis     case R_FIFO_STATUS:
310a7d2d98cSAlistair Francis         retvalue = s->uart_fifo_status;
311a7d2d98cSAlistair Francis 
31282a4ed8eSAlexander Wagner         retvalue |= (s->rx_level & 0x1F) << R_FIFO_STATUS_RXLVL_SHIFT;
31382a4ed8eSAlexander Wagner         retvalue |= (s->tx_level & 0x1F) << R_FIFO_STATUS_TXLVL_SHIFT;
314a7d2d98cSAlistair Francis 
315a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
316a7d2d98cSAlistair Francis                       "%s: RX fifos are not supported\n", __func__);
317a7d2d98cSAlistair Francis         break;
318a7d2d98cSAlistair Francis 
31959093cc4SAlistair Francis     case R_OVRD:
320a7d2d98cSAlistair Francis         retvalue = s->uart_ovrd;
321a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
322a7d2d98cSAlistair Francis                       "%s: ovrd is not supported\n", __func__);
323a7d2d98cSAlistair Francis         break;
32459093cc4SAlistair Francis     case R_VAL:
325a7d2d98cSAlistair Francis         retvalue = s->uart_val;
326a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
327a7d2d98cSAlistair Francis                       "%s: val is not supported\n", __func__);
328a7d2d98cSAlistair Francis         break;
32959093cc4SAlistair Francis     case R_TIMEOUT_CTRL:
330a7d2d98cSAlistair Francis         retvalue = s->uart_timeout_ctrl;
331a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
332a7d2d98cSAlistair Francis                       "%s: timeout_ctrl is not supported\n", __func__);
333a7d2d98cSAlistair Francis         break;
334a7d2d98cSAlistair Francis     default:
335a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
336a7d2d98cSAlistair Francis                       "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
337a7d2d98cSAlistair Francis         return 0;
338a7d2d98cSAlistair Francis     }
339a7d2d98cSAlistair Francis 
340a7d2d98cSAlistair Francis     return retvalue;
341a7d2d98cSAlistair Francis }
342a7d2d98cSAlistair Francis 
343a7d2d98cSAlistair Francis static void ibex_uart_write(void *opaque, hwaddr addr,
344a7d2d98cSAlistair Francis                                   uint64_t val64, unsigned int size)
345a7d2d98cSAlistair Francis {
346a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
347a7d2d98cSAlistair Francis     uint32_t value = val64;
348a7d2d98cSAlistair Francis 
34959093cc4SAlistair Francis     switch (addr >> 2) {
35059093cc4SAlistair Francis     case R_INTR_STATE:
351a7d2d98cSAlistair Francis         /* Write 1 clear */
352a7d2d98cSAlistair Francis         s->uart_intr_state &= ~value;
353a7d2d98cSAlistair Francis         ibex_uart_update_irqs(s);
354a7d2d98cSAlistair Francis         break;
35559093cc4SAlistair Francis     case R_INTR_ENABLE:
356a7d2d98cSAlistair Francis         s->uart_intr_enable = value;
357a7d2d98cSAlistair Francis         ibex_uart_update_irqs(s);
358a7d2d98cSAlistair Francis         break;
35959093cc4SAlistair Francis     case R_INTR_TEST:
360a7d2d98cSAlistair Francis         s->uart_intr_state |= value;
361a7d2d98cSAlistair Francis         ibex_uart_update_irqs(s);
362a7d2d98cSAlistair Francis         break;
363a7d2d98cSAlistair Francis 
36459093cc4SAlistair Francis     case R_CTRL:
365a7d2d98cSAlistair Francis         s->uart_ctrl = value;
366a7d2d98cSAlistair Francis 
36759093cc4SAlistair Francis         if (value & R_CTRL_NF_MASK) {
368a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
369a7d2d98cSAlistair Francis                           "%s: UART_CTRL_NF is not supported\n", __func__);
370a7d2d98cSAlistair Francis         }
37159093cc4SAlistair Francis         if (value & R_CTRL_SLPBK_MASK) {
372a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
373a7d2d98cSAlistair Francis                           "%s: UART_CTRL_SLPBK is not supported\n", __func__);
374a7d2d98cSAlistair Francis         }
37559093cc4SAlistair Francis         if (value & R_CTRL_LLPBK_MASK) {
376a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
377a7d2d98cSAlistair Francis                           "%s: UART_CTRL_LLPBK is not supported\n", __func__);
378a7d2d98cSAlistair Francis         }
37959093cc4SAlistair Francis         if (value & R_CTRL_PARITY_EN_MASK) {
380a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
381a7d2d98cSAlistair Francis                           "%s: UART_CTRL_PARITY_EN is not supported\n",
382a7d2d98cSAlistair Francis                           __func__);
383a7d2d98cSAlistair Francis         }
38459093cc4SAlistair Francis         if (value & R_CTRL_PARITY_ODD_MASK) {
385a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
386a7d2d98cSAlistair Francis                           "%s: UART_CTRL_PARITY_ODD is not supported\n",
387a7d2d98cSAlistair Francis                           __func__);
388a7d2d98cSAlistair Francis         }
38959093cc4SAlistair Francis         if (value & R_CTRL_RXBLVL_MASK) {
390a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
391a7d2d98cSAlistair Francis                           "%s: UART_CTRL_RXBLVL is not supported\n", __func__);
392a7d2d98cSAlistair Francis         }
39359093cc4SAlistair Francis         if (value & R_CTRL_NCO_MASK) {
394940aabb9SAlistair Francis             uint64_t baud = ibex_uart_get_baud(s);
395a7d2d98cSAlistair Francis 
396a7d2d98cSAlistair Francis             s->char_tx_time = (NANOSECONDS_PER_SECOND / baud) * 10;
397a7d2d98cSAlistair Francis         }
398a7d2d98cSAlistair Francis         break;
39959093cc4SAlistair Francis     case R_STATUS:
400a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
401a7d2d98cSAlistair Francis                       "%s: status is read only\n", __func__);
402a7d2d98cSAlistair Francis         break;
403a7d2d98cSAlistair Francis 
40459093cc4SAlistair Francis     case R_RDATA:
405a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
406a7d2d98cSAlistair Francis                       "%s: rdata is read only\n", __func__);
407a7d2d98cSAlistair Francis         break;
40859093cc4SAlistair Francis     case R_WDATA:
409a7d2d98cSAlistair Francis         uart_write_tx_fifo(s, (uint8_t *) &value, 1);
410a7d2d98cSAlistair Francis         break;
411a7d2d98cSAlistair Francis 
41259093cc4SAlistair Francis     case R_FIFO_CTRL:
413a7d2d98cSAlistair Francis         s->uart_fifo_ctrl = value;
414a7d2d98cSAlistair Francis 
41559093cc4SAlistair Francis         if (value & R_FIFO_CTRL_RXRST_MASK) {
41682a4ed8eSAlexander Wagner             s->rx_level = 0;
417a7d2d98cSAlistair Francis             qemu_log_mask(LOG_UNIMP,
418a7d2d98cSAlistair Francis                           "%s: RX fifos are not supported\n", __func__);
419a7d2d98cSAlistair Francis         }
42059093cc4SAlistair Francis         if (value & R_FIFO_CTRL_TXRST_MASK) {
421a7d2d98cSAlistair Francis             s->tx_level = 0;
422a7d2d98cSAlistair Francis         }
423a7d2d98cSAlistair Francis         break;
42459093cc4SAlistair Francis     case R_FIFO_STATUS:
425a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
426a7d2d98cSAlistair Francis                       "%s: fifo_status is read only\n", __func__);
427a7d2d98cSAlistair Francis         break;
428a7d2d98cSAlistair Francis 
42959093cc4SAlistair Francis     case R_OVRD:
430a7d2d98cSAlistair Francis         s->uart_ovrd = value;
431a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
432a7d2d98cSAlistair Francis                       "%s: ovrd is not supported\n", __func__);
433a7d2d98cSAlistair Francis         break;
43459093cc4SAlistair Francis     case R_VAL:
435a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
436a7d2d98cSAlistair Francis                       "%s: val is read only\n", __func__);
437a7d2d98cSAlistair Francis         break;
43859093cc4SAlistair Francis     case R_TIMEOUT_CTRL:
439a7d2d98cSAlistair Francis         s->uart_timeout_ctrl = value;
440a7d2d98cSAlistair Francis         qemu_log_mask(LOG_UNIMP,
441a7d2d98cSAlistair Francis                       "%s: timeout_ctrl is not supported\n", __func__);
442a7d2d98cSAlistair Francis         break;
443a7d2d98cSAlistair Francis     default:
444a7d2d98cSAlistair Francis         qemu_log_mask(LOG_GUEST_ERROR,
445a7d2d98cSAlistair Francis                       "%s: Bad offset 0x%"HWADDR_PRIx"\n", __func__, addr);
446a7d2d98cSAlistair Francis     }
447a7d2d98cSAlistair Francis }
448a7d2d98cSAlistair Francis 
4495ee0abedSPeter Maydell static void ibex_uart_clk_update(void *opaque, ClockEvent event)
450940aabb9SAlistair Francis {
451940aabb9SAlistair Francis     IbexUartState *s = opaque;
452940aabb9SAlistair Francis 
453940aabb9SAlistair Francis     /* recompute uart's speed on clock change */
454940aabb9SAlistair Francis     uint64_t baud = ibex_uart_get_baud(s);
455940aabb9SAlistair Francis 
456940aabb9SAlistair Francis     s->char_tx_time = (NANOSECONDS_PER_SECOND / baud) * 10;
457940aabb9SAlistair Francis }
458940aabb9SAlistair Francis 
459a7d2d98cSAlistair Francis static void fifo_trigger_update(void *opaque)
460a7d2d98cSAlistair Francis {
461a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
462a7d2d98cSAlistair Francis 
46359093cc4SAlistair Francis     if (s->uart_ctrl & R_CTRL_TX_ENABLE_MASK) {
464a7d2d98cSAlistair Francis         ibex_uart_xmit(NULL, G_IO_OUT, s);
465a7d2d98cSAlistair Francis     }
466a7d2d98cSAlistair Francis }
467a7d2d98cSAlistair Francis 
468a7d2d98cSAlistair Francis static const MemoryRegionOps ibex_uart_ops = {
469a7d2d98cSAlistair Francis     .read = ibex_uart_read,
470a7d2d98cSAlistair Francis     .write = ibex_uart_write,
471a7d2d98cSAlistair Francis     .endianness = DEVICE_NATIVE_ENDIAN,
472a7d2d98cSAlistair Francis     .impl.min_access_size = 4,
473a7d2d98cSAlistair Francis     .impl.max_access_size = 4,
474a7d2d98cSAlistair Francis };
475a7d2d98cSAlistair Francis 
476a7d2d98cSAlistair Francis static int ibex_uart_post_load(void *opaque, int version_id)
477a7d2d98cSAlistair Francis {
478a7d2d98cSAlistair Francis     IbexUartState *s = opaque;
479a7d2d98cSAlistair Francis 
480a7d2d98cSAlistair Francis     ibex_uart_update_irqs(s);
481a7d2d98cSAlistair Francis     return 0;
482a7d2d98cSAlistair Francis }
483a7d2d98cSAlistair Francis 
484a7d2d98cSAlistair Francis static const VMStateDescription vmstate_ibex_uart = {
485a7d2d98cSAlistair Francis     .name = TYPE_IBEX_UART,
486a7d2d98cSAlistair Francis     .version_id = 1,
487a7d2d98cSAlistair Francis     .minimum_version_id = 1,
488a7d2d98cSAlistair Francis     .post_load = ibex_uart_post_load,
489a7d2d98cSAlistair Francis     .fields = (VMStateField[]) {
490a7d2d98cSAlistair Francis         VMSTATE_UINT8_ARRAY(tx_fifo, IbexUartState,
491a7d2d98cSAlistair Francis                             IBEX_UART_TX_FIFO_SIZE),
492a7d2d98cSAlistair Francis         VMSTATE_UINT32(tx_level, IbexUartState),
493a7d2d98cSAlistair Francis         VMSTATE_UINT64(char_tx_time, IbexUartState),
494a7d2d98cSAlistair Francis         VMSTATE_TIMER_PTR(fifo_trigger_handle, IbexUartState),
495a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_intr_state, IbexUartState),
496a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_intr_enable, IbexUartState),
497a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_ctrl, IbexUartState),
498a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_status, IbexUartState),
499a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_rdata, IbexUartState),
500a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_fifo_ctrl, IbexUartState),
501a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_fifo_status, IbexUartState),
502a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_ovrd, IbexUartState),
503a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_val, IbexUartState),
504a7d2d98cSAlistair Francis         VMSTATE_UINT32(uart_timeout_ctrl, IbexUartState),
505a7d2d98cSAlistair Francis         VMSTATE_END_OF_LIST()
506a7d2d98cSAlistair Francis     }
507a7d2d98cSAlistair Francis };
508a7d2d98cSAlistair Francis 
509a7d2d98cSAlistair Francis static Property ibex_uart_properties[] = {
510a7d2d98cSAlistair Francis     DEFINE_PROP_CHR("chardev", IbexUartState, chr),
511a7d2d98cSAlistair Francis     DEFINE_PROP_END_OF_LIST(),
512a7d2d98cSAlistair Francis };
513a7d2d98cSAlistair Francis 
514a7d2d98cSAlistair Francis static void ibex_uart_init(Object *obj)
515a7d2d98cSAlistair Francis {
516a7d2d98cSAlistair Francis     IbexUartState *s = IBEX_UART(obj);
517a7d2d98cSAlistair Francis 
518940aabb9SAlistair Francis     s->f_clk = qdev_init_clock_in(DEVICE(obj), "f_clock",
5195ee0abedSPeter Maydell                                   ibex_uart_clk_update, s, ClockUpdate);
520940aabb9SAlistair Francis     clock_set_hz(s->f_clk, IBEX_UART_CLOCK);
521940aabb9SAlistair Francis 
522a7d2d98cSAlistair Francis     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->tx_watermark);
523a7d2d98cSAlistair Francis     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->rx_watermark);
524a7d2d98cSAlistair Francis     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->tx_empty);
525a7d2d98cSAlistair Francis     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->rx_overflow);
526a7d2d98cSAlistair Francis 
527a7d2d98cSAlistair Francis     memory_region_init_io(&s->mmio, obj, &ibex_uart_ops, s,
528a7d2d98cSAlistair Francis                           TYPE_IBEX_UART, 0x400);
529a7d2d98cSAlistair Francis     sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio);
530a7d2d98cSAlistair Francis }
531a7d2d98cSAlistair Francis 
532a7d2d98cSAlistair Francis static void ibex_uart_realize(DeviceState *dev, Error **errp)
533a7d2d98cSAlistair Francis {
534a7d2d98cSAlistair Francis     IbexUartState *s = IBEX_UART(dev);
535a7d2d98cSAlistair Francis 
536a7d2d98cSAlistair Francis     s->fifo_trigger_handle = timer_new_ns(QEMU_CLOCK_VIRTUAL,
537a7d2d98cSAlistair Francis                                           fifo_trigger_update, s);
538a7d2d98cSAlistair Francis 
539a7d2d98cSAlistair Francis     qemu_chr_fe_set_handlers(&s->chr, ibex_uart_can_receive,
540a7d2d98cSAlistair Francis                              ibex_uart_receive, NULL, NULL,
541a7d2d98cSAlistair Francis                              s, NULL, true);
542a7d2d98cSAlistair Francis }
543a7d2d98cSAlistair Francis 
544a7d2d98cSAlistair Francis static void ibex_uart_class_init(ObjectClass *klass, void *data)
545a7d2d98cSAlistair Francis {
546a7d2d98cSAlistair Francis     DeviceClass *dc = DEVICE_CLASS(klass);
547a7d2d98cSAlistair Francis 
548a7d2d98cSAlistair Francis     dc->reset = ibex_uart_reset;
549a7d2d98cSAlistair Francis     dc->realize = ibex_uart_realize;
550a7d2d98cSAlistair Francis     dc->vmsd = &vmstate_ibex_uart;
551a7d2d98cSAlistair Francis     device_class_set_props(dc, ibex_uart_properties);
552a7d2d98cSAlistair Francis }
553a7d2d98cSAlistair Francis 
554a7d2d98cSAlistair Francis static const TypeInfo ibex_uart_info = {
555a7d2d98cSAlistair Francis     .name          = TYPE_IBEX_UART,
556a7d2d98cSAlistair Francis     .parent        = TYPE_SYS_BUS_DEVICE,
557a7d2d98cSAlistair Francis     .instance_size = sizeof(IbexUartState),
558a7d2d98cSAlistair Francis     .instance_init = ibex_uart_init,
559a7d2d98cSAlistair Francis     .class_init    = ibex_uart_class_init,
560a7d2d98cSAlistair Francis };
561a7d2d98cSAlistair Francis 
562a7d2d98cSAlistair Francis static void ibex_uart_register_types(void)
563a7d2d98cSAlistair Francis {
564a7d2d98cSAlistair Francis     type_register_static(&ibex_uart_info);
565a7d2d98cSAlistair Francis }
566a7d2d98cSAlistair Francis 
567a7d2d98cSAlistair Francis type_init(ibex_uart_register_types)
568