xref: /openbmc/qemu/hw/i2c/aspeed_i2c.c (revision 19f70347)
1 /*
2  * ARM Aspeed I2C controller
3  *
4  * Copyright (C) 2016 IBM Corp.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
18  *
19  */
20 
21 #include "qemu/osdep.h"
22 #include "hw/sysbus.h"
23 #include "migration/vmstate.h"
24 #include "qemu/log.h"
25 #include "qemu/module.h"
26 #include "qemu/error-report.h"
27 #include "qapi/error.h"
28 #include "hw/i2c/aspeed_i2c.h"
29 #include "hw/irq.h"
30 #include "hw/qdev-properties.h"
31 #include "trace.h"
32 
33 /* I2C Global Register */
34 
35 #define I2C_CTRL_STATUS         0x00        /* Device Interrupt Status */
36 #define I2C_CTRL_ASSIGN         0x08        /* Device Interrupt Target
37                                                Assignment */
38 #define I2C_CTRL_GLOBAL         0x0C        /* Global Control Register */
39 #define   I2C_CTRL_SRAM_EN                 BIT(0)
40 
41 /* I2C Device (Bus) Register */
42 
43 #define I2CD_FUN_CTRL_REG       0x00       /* I2CD Function Control  */
44 #define   I2CD_POOL_PAGE_SEL(x)            (((x) >> 20) & 0x7)  /* AST2400 */
45 #define   I2CD_M_SDA_LOCK_EN               (0x1 << 16)
46 #define   I2CD_MULTI_MASTER_DIS            (0x1 << 15)
47 #define   I2CD_M_SCL_DRIVE_EN              (0x1 << 14)
48 #define   I2CD_MSB_STS                     (0x1 << 9)
49 #define   I2CD_SDA_DRIVE_1T_EN             (0x1 << 8)
50 #define   I2CD_M_SDA_DRIVE_1T_EN           (0x1 << 7)
51 #define   I2CD_M_HIGH_SPEED_EN             (0x1 << 6)
52 #define   I2CD_DEF_ADDR_EN                 (0x1 << 5)
53 #define   I2CD_DEF_ALERT_EN                (0x1 << 4)
54 #define   I2CD_DEF_ARP_EN                  (0x1 << 3)
55 #define   I2CD_DEF_GCALL_EN                (0x1 << 2)
56 #define   I2CD_SLAVE_EN                    (0x1 << 1)
57 #define   I2CD_MASTER_EN                   (0x1)
58 
59 #define I2CD_AC_TIMING_REG1     0x04       /* Clock and AC Timing Control #1 */
60 #define I2CD_AC_TIMING_REG2     0x08       /* Clock and AC Timing Control #1 */
61 #define I2CD_INTR_CTRL_REG      0x0c       /* I2CD Interrupt Control */
62 #define I2CD_INTR_STS_REG       0x10       /* I2CD Interrupt Status */
63 
64 #define   I2CD_INTR_SLAVE_ADDR_MATCH       (0x1 << 31) /* 0: addr1 1: addr2 */
65 #define   I2CD_INTR_SLAVE_ADDR_RX_PENDING  (0x1 << 30)
66 /* bits[19-16] Reserved */
67 
68 /* All bits below are cleared by writing 1 */
69 #define   I2CD_INTR_SLAVE_INACTIVE_TIMEOUT (0x1 << 15)
70 #define   I2CD_INTR_SDA_DL_TIMEOUT         (0x1 << 14)
71 #define   I2CD_INTR_BUS_RECOVER_DONE       (0x1 << 13)
72 #define   I2CD_INTR_SMBUS_ALERT            (0x1 << 12) /* Bus [0-3] only */
73 #define   I2CD_INTR_SMBUS_ARP_ADDR         (0x1 << 11) /* Removed */
74 #define   I2CD_INTR_SMBUS_DEV_ALERT_ADDR   (0x1 << 10) /* Removed */
75 #define   I2CD_INTR_SMBUS_DEF_ADDR         (0x1 << 9)  /* Removed */
76 #define   I2CD_INTR_GCALL_ADDR             (0x1 << 8)  /* Removed */
77 #define   I2CD_INTR_SLAVE_ADDR_RX_MATCH    (0x1 << 7)  /* use RX_DONE */
78 #define   I2CD_INTR_SCL_TIMEOUT            (0x1 << 6)
79 #define   I2CD_INTR_ABNORMAL               (0x1 << 5)
80 #define   I2CD_INTR_NORMAL_STOP            (0x1 << 4)
81 #define   I2CD_INTR_ARBIT_LOSS             (0x1 << 3)
82 #define   I2CD_INTR_RX_DONE                (0x1 << 2)
83 #define   I2CD_INTR_TX_NAK                 (0x1 << 1)
84 #define   I2CD_INTR_TX_ACK                 (0x1 << 0)
85 
86 #define I2CD_CMD_REG            0x14       /* I2CD Command/Status */
87 #define   I2CD_SDA_OE                      (0x1 << 28)
88 #define   I2CD_SDA_O                       (0x1 << 27)
89 #define   I2CD_SCL_OE                      (0x1 << 26)
90 #define   I2CD_SCL_O                       (0x1 << 25)
91 #define   I2CD_TX_TIMING                   (0x1 << 24)
92 #define   I2CD_TX_STATUS                   (0x1 << 23)
93 
94 #define   I2CD_TX_STATE_SHIFT              19 /* Tx State Machine */
95 #define   I2CD_TX_STATE_MASK                  0xf
96 #define     I2CD_IDLE                         0x0
97 #define     I2CD_MACTIVE                      0x8
98 #define     I2CD_MSTART                       0x9
99 #define     I2CD_MSTARTR                      0xa
100 #define     I2CD_MSTOP                        0xb
101 #define     I2CD_MTXD                         0xc
102 #define     I2CD_MRXACK                       0xd
103 #define     I2CD_MRXD                         0xe
104 #define     I2CD_MTXACK                       0xf
105 #define     I2CD_SWAIT                        0x1
106 #define     I2CD_SRXD                         0x4
107 #define     I2CD_STXACK                       0x5
108 #define     I2CD_STXD                         0x6
109 #define     I2CD_SRXACK                       0x7
110 #define     I2CD_RECOVER                      0x3
111 
112 #define   I2CD_SCL_LINE_STS                (0x1 << 18)
113 #define   I2CD_SDA_LINE_STS                (0x1 << 17)
114 #define   I2CD_BUS_BUSY_STS                (0x1 << 16)
115 #define   I2CD_SDA_OE_OUT_DIR              (0x1 << 15)
116 #define   I2CD_SDA_O_OUT_DIR               (0x1 << 14)
117 #define   I2CD_SCL_OE_OUT_DIR              (0x1 << 13)
118 #define   I2CD_SCL_O_OUT_DIR               (0x1 << 12)
119 #define   I2CD_BUS_RECOVER_CMD_EN          (0x1 << 11)
120 #define   I2CD_S_ALT_EN                    (0x1 << 10)
121 
122 /* Command Bit */
123 #define   I2CD_RX_DMA_ENABLE               (0x1 << 9)
124 #define   I2CD_TX_DMA_ENABLE               (0x1 << 8)
125 #define   I2CD_RX_BUFF_ENABLE              (0x1 << 7)
126 #define   I2CD_TX_BUFF_ENABLE              (0x1 << 6)
127 #define   I2CD_M_STOP_CMD                  (0x1 << 5)
128 #define   I2CD_M_S_RX_CMD_LAST             (0x1 << 4)
129 #define   I2CD_M_RX_CMD                    (0x1 << 3)
130 #define   I2CD_S_TX_CMD                    (0x1 << 2)
131 #define   I2CD_M_TX_CMD                    (0x1 << 1)
132 #define   I2CD_M_START_CMD                 (0x1)
133 
134 #define I2CD_DEV_ADDR_REG       0x18       /* Slave Device Address */
135 #define I2CD_POOL_CTRL_REG      0x1c       /* Pool Buffer Control */
136 #define   I2CD_POOL_RX_COUNT(x)            (((x) >> 24) & 0xff)
137 #define   I2CD_POOL_RX_SIZE(x)             ((((x) >> 16) & 0xff) + 1)
138 #define   I2CD_POOL_TX_COUNT(x)            ((((x) >> 8) & 0xff) + 1)
139 #define   I2CD_POOL_OFFSET(x)              (((x) & 0x3f) << 2)  /* AST2400 */
140 #define I2CD_BYTE_BUF_REG       0x20       /* Transmit/Receive Byte Buffer */
141 #define   I2CD_BYTE_BUF_TX_SHIFT           0
142 #define   I2CD_BYTE_BUF_TX_MASK            0xff
143 #define   I2CD_BYTE_BUF_RX_SHIFT           8
144 #define   I2CD_BYTE_BUF_RX_MASK            0xff
145 #define I2CD_DMA_ADDR           0x24       /* DMA Buffer Address */
146 #define I2CD_DMA_LEN            0x28       /* DMA Transfer Length < 4KB */
147 
148 static inline bool aspeed_i2c_bus_is_master(AspeedI2CBus *bus)
149 {
150     return bus->ctrl & I2CD_MASTER_EN;
151 }
152 
153 static inline bool aspeed_i2c_bus_is_enabled(AspeedI2CBus *bus)
154 {
155     return bus->ctrl & (I2CD_MASTER_EN | I2CD_SLAVE_EN);
156 }
157 
158 static inline void aspeed_i2c_bus_raise_interrupt(AspeedI2CBus *bus)
159 {
160     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
161 
162     trace_aspeed_i2c_bus_raise_interrupt(bus->intr_status,
163           bus->intr_status & I2CD_INTR_TX_NAK ? "nak|" : "",
164           bus->intr_status & I2CD_INTR_TX_ACK ? "ack|" : "",
165           bus->intr_status & I2CD_INTR_RX_DONE ? "done|" : "",
166           bus->intr_status & I2CD_INTR_NORMAL_STOP ? "normal|" : "",
167           bus->intr_status & I2CD_INTR_ABNORMAL ? "abnormal" : "");
168 
169     bus->intr_status &= bus->intr_ctrl;
170     if (bus->intr_status) {
171         bus->controller->intr_status |= 1 << bus->id;
172         qemu_irq_raise(aic->bus_get_irq(bus));
173     }
174 }
175 
176 static uint64_t aspeed_i2c_bus_read(void *opaque, hwaddr offset,
177                                     unsigned size)
178 {
179     AspeedI2CBus *bus = opaque;
180     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
181     uint64_t value = -1;
182 
183     switch (offset) {
184     case I2CD_FUN_CTRL_REG:
185         value = bus->ctrl;
186         break;
187     case I2CD_AC_TIMING_REG1:
188         value = bus->timing[0];
189         break;
190     case I2CD_AC_TIMING_REG2:
191         value = bus->timing[1];
192         break;
193     case I2CD_INTR_CTRL_REG:
194         value = bus->intr_ctrl;
195         break;
196     case I2CD_INTR_STS_REG:
197         value = bus->intr_status;
198         break;
199     case I2CD_POOL_CTRL_REG:
200         value = bus->pool_ctrl;
201         break;
202     case I2CD_BYTE_BUF_REG:
203         value = bus->buf;
204         break;
205     case I2CD_CMD_REG:
206         value = bus->cmd | (i2c_bus_busy(bus->bus) << 16);
207         break;
208     case I2CD_DMA_ADDR:
209         if (!aic->has_dma) {
210             qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n",  __func__);
211             break;
212         }
213         value = bus->dma_addr;
214         break;
215     case I2CD_DMA_LEN:
216         if (!aic->has_dma) {
217             qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n",  __func__);
218             break;
219         }
220         value = bus->dma_len;
221         break;
222 
223     default:
224         qemu_log_mask(LOG_GUEST_ERROR,
225                       "%s: Bad offset 0x%" HWADDR_PRIx "\n", __func__, offset);
226         value = -1;
227         break;
228     }
229 
230     trace_aspeed_i2c_bus_read(bus->id, offset, size, value);
231     return value;
232 }
233 
234 static void aspeed_i2c_set_state(AspeedI2CBus *bus, uint8_t state)
235 {
236     bus->cmd &= ~(I2CD_TX_STATE_MASK << I2CD_TX_STATE_SHIFT);
237     bus->cmd |= (state & I2CD_TX_STATE_MASK) << I2CD_TX_STATE_SHIFT;
238 }
239 
240 static uint8_t aspeed_i2c_get_state(AspeedI2CBus *bus)
241 {
242     return (bus->cmd >> I2CD_TX_STATE_SHIFT) & I2CD_TX_STATE_MASK;
243 }
244 
245 static int aspeed_i2c_dma_read(AspeedI2CBus *bus, uint8_t *data)
246 {
247     MemTxResult result;
248     AspeedI2CState *s = bus->controller;
249 
250     result = address_space_read(&s->dram_as, bus->dma_addr,
251                                 MEMTXATTRS_UNSPECIFIED, data, 1);
252     if (result != MEMTX_OK) {
253         qemu_log_mask(LOG_GUEST_ERROR, "%s: DRAM read failed @%08x\n",
254                       __func__, bus->dma_addr);
255         return -1;
256     }
257 
258     bus->dma_addr++;
259     bus->dma_len--;
260     return 0;
261 }
262 
263 static int aspeed_i2c_bus_send(AspeedI2CBus *bus, uint8_t pool_start)
264 {
265     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
266     int ret = -1;
267     int i;
268 
269     if (bus->cmd & I2CD_TX_BUFF_ENABLE) {
270         for (i = pool_start; i < I2CD_POOL_TX_COUNT(bus->pool_ctrl); i++) {
271             uint8_t *pool_base = aic->bus_pool_base(bus);
272 
273             trace_aspeed_i2c_bus_send("BUF", i + 1,
274                                       I2CD_POOL_TX_COUNT(bus->pool_ctrl),
275                                       pool_base[i]);
276             ret = i2c_send(bus->bus, pool_base[i]);
277             if (ret) {
278                 break;
279             }
280         }
281         bus->cmd &= ~I2CD_TX_BUFF_ENABLE;
282     } else if (bus->cmd & I2CD_TX_DMA_ENABLE) {
283         while (bus->dma_len) {
284             uint8_t data;
285             aspeed_i2c_dma_read(bus, &data);
286             trace_aspeed_i2c_bus_send("DMA", bus->dma_len, bus->dma_len, data);
287             ret = i2c_send(bus->bus, data);
288             if (ret) {
289                 break;
290             }
291         }
292         bus->cmd &= ~I2CD_TX_DMA_ENABLE;
293     } else {
294         trace_aspeed_i2c_bus_send("BYTE", pool_start, 1, bus->buf);
295         ret = i2c_send(bus->bus, bus->buf);
296     }
297 
298     return ret;
299 }
300 
301 static void aspeed_i2c_bus_recv(AspeedI2CBus *bus)
302 {
303     AspeedI2CState *s = bus->controller;
304     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
305     uint8_t data;
306     int i;
307 
308     if (bus->cmd & I2CD_RX_BUFF_ENABLE) {
309         uint8_t *pool_base = aic->bus_pool_base(bus);
310 
311         for (i = 0; i < I2CD_POOL_RX_SIZE(bus->pool_ctrl); i++) {
312             pool_base[i] = i2c_recv(bus->bus);
313             trace_aspeed_i2c_bus_recv("BUF", i + 1,
314                                       I2CD_POOL_RX_SIZE(bus->pool_ctrl),
315                                       pool_base[i]);
316         }
317 
318         /* Update RX count */
319         bus->pool_ctrl &= ~(0xff << 24);
320         bus->pool_ctrl |= (i & 0xff) << 24;
321         bus->cmd &= ~I2CD_RX_BUFF_ENABLE;
322     } else if (bus->cmd & I2CD_RX_DMA_ENABLE) {
323         uint8_t data;
324 
325         while (bus->dma_len) {
326             MemTxResult result;
327 
328             data = i2c_recv(bus->bus);
329             trace_aspeed_i2c_bus_recv("DMA", bus->dma_len, bus->dma_len, data);
330             result = address_space_write(&s->dram_as, bus->dma_addr,
331                                          MEMTXATTRS_UNSPECIFIED, &data, 1);
332             if (result != MEMTX_OK) {
333                 qemu_log_mask(LOG_GUEST_ERROR, "%s: DRAM write failed @%08x\n",
334                               __func__, bus->dma_addr);
335                 return;
336             }
337             bus->dma_addr++;
338             bus->dma_len--;
339         }
340         bus->cmd &= ~I2CD_RX_DMA_ENABLE;
341     } else {
342         data = i2c_recv(bus->bus);
343         trace_aspeed_i2c_bus_recv("BYTE", 1, 1, bus->buf);
344         bus->buf = (data & I2CD_BYTE_BUF_RX_MASK) << I2CD_BYTE_BUF_RX_SHIFT;
345     }
346 }
347 
348 static void aspeed_i2c_handle_rx_cmd(AspeedI2CBus *bus)
349 {
350     aspeed_i2c_set_state(bus, I2CD_MRXD);
351     aspeed_i2c_bus_recv(bus);
352     bus->intr_status |= I2CD_INTR_RX_DONE;
353     if (bus->cmd & I2CD_M_S_RX_CMD_LAST) {
354         i2c_nack(bus->bus);
355     }
356     bus->cmd &= ~(I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST);
357     aspeed_i2c_set_state(bus, I2CD_MACTIVE);
358 }
359 
360 static uint8_t aspeed_i2c_get_addr(AspeedI2CBus *bus)
361 {
362     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
363 
364     if (bus->cmd & I2CD_TX_BUFF_ENABLE) {
365         uint8_t *pool_base = aic->bus_pool_base(bus);
366 
367         return pool_base[0];
368     } else if (bus->cmd & I2CD_TX_DMA_ENABLE) {
369         uint8_t data;
370 
371         aspeed_i2c_dma_read(bus, &data);
372         return data;
373     } else {
374         return bus->buf;
375     }
376 }
377 
378 static bool aspeed_i2c_check_sram(AspeedI2CBus *bus)
379 {
380     AspeedI2CState *s = bus->controller;
381     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
382 
383     if (!aic->check_sram) {
384         return true;
385     }
386 
387     /*
388      * AST2500: SRAM must be enabled before using the Buffer Pool or
389      * DMA mode.
390      */
391     if (!(s->ctrl_global & I2C_CTRL_SRAM_EN) &&
392         (bus->cmd & (I2CD_RX_DMA_ENABLE | I2CD_TX_DMA_ENABLE |
393                      I2CD_RX_BUFF_ENABLE | I2CD_TX_BUFF_ENABLE))) {
394         qemu_log_mask(LOG_GUEST_ERROR, "%s: SRAM is not enabled\n", __func__);
395         return false;
396     }
397 
398     return true;
399 }
400 
401 static void aspeed_i2c_bus_cmd_dump(AspeedI2CBus *bus)
402 {
403     g_autofree char *cmd_flags = NULL;
404     uint32_t count;
405 
406     if (bus->cmd & (I2CD_RX_BUFF_ENABLE | I2CD_RX_BUFF_ENABLE)) {
407         count = I2CD_POOL_TX_COUNT(bus->pool_ctrl);
408     } else if (bus->cmd & (I2CD_RX_DMA_ENABLE | I2CD_RX_DMA_ENABLE)) {
409         count = bus->dma_len;
410     } else { /* BYTE mode */
411         count = 1;
412     }
413 
414     cmd_flags = g_strdup_printf("%s%s%s%s%s%s%s%s%s",
415                                 bus->cmd & I2CD_M_START_CMD ? "start|" : "",
416                                 bus->cmd & I2CD_RX_DMA_ENABLE ? "rxdma|" : "",
417                                 bus->cmd & I2CD_TX_DMA_ENABLE ? "txdma|" : "",
418                                 bus->cmd & I2CD_RX_BUFF_ENABLE ? "rxbuf|" : "",
419                                 bus->cmd & I2CD_TX_BUFF_ENABLE ? "txbuf|" : "",
420                                 bus->cmd & I2CD_M_TX_CMD ? "tx|" : "",
421                                 bus->cmd & I2CD_M_RX_CMD ? "rx|" : "",
422                                 bus->cmd & I2CD_M_S_RX_CMD_LAST ? "last|" : "",
423                                 bus->cmd & I2CD_M_STOP_CMD ? "stop" : "");
424 
425     trace_aspeed_i2c_bus_cmd(bus->cmd, cmd_flags, count, bus->intr_status);
426 }
427 
428 /*
429  * The state machine needs some refinement. It is only used to track
430  * invalid STOP commands for the moment.
431  */
432 static void aspeed_i2c_bus_handle_cmd(AspeedI2CBus *bus, uint64_t value)
433 {
434     uint8_t pool_start = 0;
435 
436     bus->cmd &= ~0xFFFF;
437     bus->cmd |= value & 0xFFFF;
438 
439     if (!aspeed_i2c_check_sram(bus)) {
440         return;
441     }
442 
443     if (trace_event_get_state_backends(TRACE_ASPEED_I2C_BUS_CMD)) {
444         aspeed_i2c_bus_cmd_dump(bus);
445     }
446 
447     if (bus->cmd & I2CD_M_START_CMD) {
448         uint8_t state = aspeed_i2c_get_state(bus) & I2CD_MACTIVE ?
449             I2CD_MSTARTR : I2CD_MSTART;
450         uint8_t addr;
451 
452         aspeed_i2c_set_state(bus, state);
453 
454         addr = aspeed_i2c_get_addr(bus);
455 
456         if (i2c_start_transfer(bus->bus, extract32(addr, 1, 7),
457                                extract32(addr, 0, 1))) {
458             bus->intr_status |= I2CD_INTR_TX_NAK;
459         } else {
460             bus->intr_status |= I2CD_INTR_TX_ACK;
461         }
462 
463         bus->cmd &= ~I2CD_M_START_CMD;
464 
465         /*
466          * The START command is also a TX command, as the slave
467          * address is sent on the bus. Drop the TX flag if nothing
468          * else needs to be sent in this sequence.
469          */
470         if (bus->cmd & I2CD_TX_BUFF_ENABLE) {
471             if (I2CD_POOL_TX_COUNT(bus->pool_ctrl) == 1) {
472                 bus->cmd &= ~I2CD_M_TX_CMD;
473             } else {
474                 /*
475                  * Increase the start index in the TX pool buffer to
476                  * skip the address byte.
477                  */
478                 pool_start++;
479             }
480         } else if (bus->cmd & I2CD_TX_DMA_ENABLE) {
481             if (bus->dma_len == 0) {
482                 bus->cmd &= ~I2CD_M_TX_CMD;
483             }
484         } else {
485             bus->cmd &= ~I2CD_M_TX_CMD;
486         }
487 
488         /* No slave found */
489         if (!i2c_bus_busy(bus->bus)) {
490             return;
491         }
492         aspeed_i2c_set_state(bus, I2CD_MACTIVE);
493     }
494 
495     if (bus->cmd & I2CD_M_TX_CMD) {
496         aspeed_i2c_set_state(bus, I2CD_MTXD);
497         if (aspeed_i2c_bus_send(bus, pool_start)) {
498             bus->intr_status |= (I2CD_INTR_TX_NAK);
499             i2c_end_transfer(bus->bus);
500         } else {
501             bus->intr_status |= I2CD_INTR_TX_ACK;
502         }
503         bus->cmd &= ~I2CD_M_TX_CMD;
504         aspeed_i2c_set_state(bus, I2CD_MACTIVE);
505     }
506 
507     if ((bus->cmd & (I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST)) &&
508         !(bus->intr_status & I2CD_INTR_RX_DONE)) {
509         aspeed_i2c_handle_rx_cmd(bus);
510     }
511 
512     if (bus->cmd & I2CD_M_STOP_CMD) {
513         if (!(aspeed_i2c_get_state(bus) & I2CD_MACTIVE)) {
514             qemu_log_mask(LOG_GUEST_ERROR, "%s: abnormal stop\n", __func__);
515             bus->intr_status |= I2CD_INTR_ABNORMAL;
516         } else {
517             aspeed_i2c_set_state(bus, I2CD_MSTOP);
518             i2c_end_transfer(bus->bus);
519             bus->intr_status |= I2CD_INTR_NORMAL_STOP;
520         }
521         bus->cmd &= ~I2CD_M_STOP_CMD;
522         aspeed_i2c_set_state(bus, I2CD_IDLE);
523     }
524 }
525 
526 static void aspeed_i2c_bus_write(void *opaque, hwaddr offset,
527                                  uint64_t value, unsigned size)
528 {
529     AspeedI2CBus *bus = opaque;
530     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(bus->controller);
531     bool handle_rx;
532 
533     trace_aspeed_i2c_bus_write(bus->id, offset, size, value);
534 
535     switch (offset) {
536     case I2CD_FUN_CTRL_REG:
537         if (value & I2CD_SLAVE_EN) {
538             qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n",
539                           __func__);
540             break;
541         }
542         bus->ctrl = value & 0x0071C3FF;
543         break;
544     case I2CD_AC_TIMING_REG1:
545         bus->timing[0] = value & 0xFFFFF0F;
546         break;
547     case I2CD_AC_TIMING_REG2:
548         bus->timing[1] = value & 0x7;
549         break;
550     case I2CD_INTR_CTRL_REG:
551         bus->intr_ctrl = value & 0x7FFF;
552         break;
553     case I2CD_INTR_STS_REG:
554         handle_rx = (bus->intr_status & I2CD_INTR_RX_DONE) &&
555                 (value & I2CD_INTR_RX_DONE);
556         bus->intr_status &= ~(value & 0x7FFF);
557         if (!bus->intr_status) {
558             bus->controller->intr_status &= ~(1 << bus->id);
559             qemu_irq_lower(aic->bus_get_irq(bus));
560         }
561         if (handle_rx && (bus->cmd & (I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST))) {
562             aspeed_i2c_handle_rx_cmd(bus);
563             aspeed_i2c_bus_raise_interrupt(bus);
564         }
565         break;
566     case I2CD_DEV_ADDR_REG:
567         qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n",
568                       __func__);
569         break;
570     case I2CD_POOL_CTRL_REG:
571         bus->pool_ctrl &= ~0xffffff;
572         bus->pool_ctrl |= (value & 0xffffff);
573         break;
574 
575     case I2CD_BYTE_BUF_REG:
576         bus->buf = (value & I2CD_BYTE_BUF_TX_MASK) << I2CD_BYTE_BUF_TX_SHIFT;
577         break;
578     case I2CD_CMD_REG:
579         if (!aspeed_i2c_bus_is_enabled(bus)) {
580             break;
581         }
582 
583         if (!aspeed_i2c_bus_is_master(bus)) {
584             qemu_log_mask(LOG_UNIMP, "%s: slave mode not implemented\n",
585                           __func__);
586             break;
587         }
588 
589         if (!aic->has_dma &&
590             value & (I2CD_RX_DMA_ENABLE | I2CD_TX_DMA_ENABLE)) {
591             qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n",  __func__);
592             break;
593         }
594 
595         aspeed_i2c_bus_handle_cmd(bus, value);
596         aspeed_i2c_bus_raise_interrupt(bus);
597         break;
598     case I2CD_DMA_ADDR:
599         if (!aic->has_dma) {
600             qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n",  __func__);
601             break;
602         }
603 
604         bus->dma_addr = value & 0xfffffffc;
605         break;
606 
607     case I2CD_DMA_LEN:
608         if (!aic->has_dma) {
609             qemu_log_mask(LOG_GUEST_ERROR, "%s: No DMA support\n",  __func__);
610             break;
611         }
612 
613         bus->dma_len = value & 0xfff;
614         if (!bus->dma_len) {
615             qemu_log_mask(LOG_UNIMP, "%s: invalid DMA length\n",  __func__);
616         }
617         break;
618 
619     default:
620         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n",
621                       __func__, offset);
622     }
623 }
624 
625 static uint64_t aspeed_i2c_ctrl_read(void *opaque, hwaddr offset,
626                                    unsigned size)
627 {
628     AspeedI2CState *s = opaque;
629 
630     switch (offset) {
631     case I2C_CTRL_STATUS:
632         return s->intr_status;
633     case I2C_CTRL_GLOBAL:
634         return s->ctrl_global;
635     default:
636         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n",
637                       __func__, offset);
638         break;
639     }
640 
641     return -1;
642 }
643 
644 static void aspeed_i2c_ctrl_write(void *opaque, hwaddr offset,
645                                   uint64_t value, unsigned size)
646 {
647     AspeedI2CState *s = opaque;
648 
649     switch (offset) {
650     case I2C_CTRL_GLOBAL:
651         s->ctrl_global = value;
652         break;
653     case I2C_CTRL_STATUS:
654     default:
655         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset 0x%" HWADDR_PRIx "\n",
656                       __func__, offset);
657         break;
658     }
659 }
660 
661 static const MemoryRegionOps aspeed_i2c_bus_ops = {
662     .read = aspeed_i2c_bus_read,
663     .write = aspeed_i2c_bus_write,
664     .endianness = DEVICE_LITTLE_ENDIAN,
665 };
666 
667 static const MemoryRegionOps aspeed_i2c_ctrl_ops = {
668     .read = aspeed_i2c_ctrl_read,
669     .write = aspeed_i2c_ctrl_write,
670     .endianness = DEVICE_LITTLE_ENDIAN,
671 };
672 
673 static uint64_t aspeed_i2c_pool_read(void *opaque, hwaddr offset,
674                                      unsigned size)
675 {
676     AspeedI2CState *s = opaque;
677     uint64_t ret = 0;
678     int i;
679 
680     for (i = 0; i < size; i++) {
681         ret |= (uint64_t) s->pool[offset + i] << (8 * i);
682     }
683 
684     return ret;
685 }
686 
687 static void aspeed_i2c_pool_write(void *opaque, hwaddr offset,
688                                   uint64_t value, unsigned size)
689 {
690     AspeedI2CState *s = opaque;
691     int i;
692 
693     for (i = 0; i < size; i++) {
694         s->pool[offset + i] = (value >> (8 * i)) & 0xFF;
695     }
696 }
697 
698 static const MemoryRegionOps aspeed_i2c_pool_ops = {
699     .read = aspeed_i2c_pool_read,
700     .write = aspeed_i2c_pool_write,
701     .endianness = DEVICE_LITTLE_ENDIAN,
702     .valid = {
703         .min_access_size = 1,
704         .max_access_size = 4,
705     },
706 };
707 
708 static const VMStateDescription aspeed_i2c_bus_vmstate = {
709     .name = TYPE_ASPEED_I2C,
710     .version_id = 3,
711     .minimum_version_id = 3,
712     .fields = (VMStateField[]) {
713         VMSTATE_UINT8(id, AspeedI2CBus),
714         VMSTATE_UINT32(ctrl, AspeedI2CBus),
715         VMSTATE_UINT32_ARRAY(timing, AspeedI2CBus, 2),
716         VMSTATE_UINT32(intr_ctrl, AspeedI2CBus),
717         VMSTATE_UINT32(intr_status, AspeedI2CBus),
718         VMSTATE_UINT32(cmd, AspeedI2CBus),
719         VMSTATE_UINT32(buf, AspeedI2CBus),
720         VMSTATE_UINT32(pool_ctrl, AspeedI2CBus),
721         VMSTATE_UINT32(dma_addr, AspeedI2CBus),
722         VMSTATE_UINT32(dma_len, AspeedI2CBus),
723         VMSTATE_END_OF_LIST()
724     }
725 };
726 
727 static const VMStateDescription aspeed_i2c_vmstate = {
728     .name = TYPE_ASPEED_I2C,
729     .version_id = 2,
730     .minimum_version_id = 2,
731     .fields = (VMStateField[]) {
732         VMSTATE_UINT32(intr_status, AspeedI2CState),
733         VMSTATE_STRUCT_ARRAY(busses, AspeedI2CState,
734                              ASPEED_I2C_NR_BUSSES, 1, aspeed_i2c_bus_vmstate,
735                              AspeedI2CBus),
736         VMSTATE_UINT8_ARRAY(pool, AspeedI2CState, ASPEED_I2C_MAX_POOL_SIZE),
737         VMSTATE_END_OF_LIST()
738     }
739 };
740 
741 static void aspeed_i2c_reset(DeviceState *dev)
742 {
743     int i;
744     AspeedI2CState *s = ASPEED_I2C(dev);
745     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
746 
747     s->intr_status = 0;
748 
749     for (i = 0; i < aic->num_busses; i++) {
750         s->busses[i].intr_ctrl = 0;
751         s->busses[i].intr_status = 0;
752         s->busses[i].cmd = 0;
753         s->busses[i].buf = 0;
754         s->busses[i].dma_addr = 0;
755         s->busses[i].dma_len = 0;
756         i2c_end_transfer(s->busses[i].bus);
757     }
758 }
759 
760 /*
761  * Address Definitions (AST2400 and AST2500)
762  *
763  *   0x000 ... 0x03F: Global Register
764  *   0x040 ... 0x07F: Device 1
765  *   0x080 ... 0x0BF: Device 2
766  *   0x0C0 ... 0x0FF: Device 3
767  *   0x100 ... 0x13F: Device 4
768  *   0x140 ... 0x17F: Device 5
769  *   0x180 ... 0x1BF: Device 6
770  *   0x1C0 ... 0x1FF: Device 7
771  *   0x200 ... 0x2FF: Buffer Pool  (unused in linux driver)
772  *   0x300 ... 0x33F: Device 8
773  *   0x340 ... 0x37F: Device 9
774  *   0x380 ... 0x3BF: Device 10
775  *   0x3C0 ... 0x3FF: Device 11
776  *   0x400 ... 0x43F: Device 12
777  *   0x440 ... 0x47F: Device 13
778  *   0x480 ... 0x4BF: Device 14
779  *   0x800 ... 0xFFF: Buffer Pool  (unused in linux driver)
780  */
781 static void aspeed_i2c_realize(DeviceState *dev, Error **errp)
782 {
783     int i;
784     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
785     AspeedI2CState *s = ASPEED_I2C(dev);
786     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
787 
788     sysbus_init_irq(sbd, &s->irq);
789     memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_i2c_ctrl_ops, s,
790                           "aspeed.i2c", 0x1000);
791     sysbus_init_mmio(sbd, &s->iomem);
792 
793     for (i = 0; i < aic->num_busses; i++) {
794         char name[32];
795         int offset = i < aic->gap ? 1 : 5;
796 
797         sysbus_init_irq(sbd, &s->busses[i].irq);
798         snprintf(name, sizeof(name), "aspeed.i2c.%d", i);
799         s->busses[i].controller = s;
800         s->busses[i].id = i;
801         s->busses[i].bus = i2c_init_bus(dev, name);
802         memory_region_init_io(&s->busses[i].mr, OBJECT(dev),
803                               &aspeed_i2c_bus_ops, &s->busses[i], name,
804                               aic->reg_size);
805         memory_region_add_subregion(&s->iomem, aic->reg_size * (i + offset),
806                                     &s->busses[i].mr);
807     }
808 
809     memory_region_init_io(&s->pool_iomem, OBJECT(s), &aspeed_i2c_pool_ops, s,
810                           "aspeed.i2c-pool", aic->pool_size);
811     memory_region_add_subregion(&s->iomem, aic->pool_base, &s->pool_iomem);
812 
813     if (aic->has_dma) {
814         if (!s->dram_mr) {
815             error_setg(errp, TYPE_ASPEED_I2C ": 'dram' link not set");
816             return;
817         }
818 
819         address_space_init(&s->dram_as, s->dram_mr, "dma-dram");
820     }
821 }
822 
823 static Property aspeed_i2c_properties[] = {
824     DEFINE_PROP_LINK("dram", AspeedI2CState, dram_mr,
825                      TYPE_MEMORY_REGION, MemoryRegion *),
826     DEFINE_PROP_END_OF_LIST(),
827 };
828 
829 static void aspeed_i2c_class_init(ObjectClass *klass, void *data)
830 {
831     DeviceClass *dc = DEVICE_CLASS(klass);
832 
833     dc->vmsd = &aspeed_i2c_vmstate;
834     dc->reset = aspeed_i2c_reset;
835     device_class_set_props(dc, aspeed_i2c_properties);
836     dc->realize = aspeed_i2c_realize;
837     dc->desc = "Aspeed I2C Controller";
838 }
839 
840 static const TypeInfo aspeed_i2c_info = {
841     .name          = TYPE_ASPEED_I2C,
842     .parent        = TYPE_SYS_BUS_DEVICE,
843     .instance_size = sizeof(AspeedI2CState),
844     .class_init    = aspeed_i2c_class_init,
845     .class_size = sizeof(AspeedI2CClass),
846     .abstract   = true,
847 };
848 
849 static qemu_irq aspeed_2400_i2c_bus_get_irq(AspeedI2CBus *bus)
850 {
851     return bus->controller->irq;
852 }
853 
854 static uint8_t *aspeed_2400_i2c_bus_pool_base(AspeedI2CBus *bus)
855 {
856     uint8_t *pool_page =
857         &bus->controller->pool[I2CD_POOL_PAGE_SEL(bus->ctrl) * 0x100];
858 
859     return &pool_page[I2CD_POOL_OFFSET(bus->pool_ctrl)];
860 }
861 
862 static void aspeed_2400_i2c_class_init(ObjectClass *klass, void *data)
863 {
864     DeviceClass *dc = DEVICE_CLASS(klass);
865     AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass);
866 
867     dc->desc = "ASPEED 2400 I2C Controller";
868 
869     aic->num_busses = 14;
870     aic->reg_size = 0x40;
871     aic->gap = 7;
872     aic->bus_get_irq = aspeed_2400_i2c_bus_get_irq;
873     aic->pool_size = 0x800;
874     aic->pool_base = 0x800;
875     aic->bus_pool_base = aspeed_2400_i2c_bus_pool_base;
876 }
877 
878 static const TypeInfo aspeed_2400_i2c_info = {
879     .name = TYPE_ASPEED_2400_I2C,
880     .parent = TYPE_ASPEED_I2C,
881     .class_init = aspeed_2400_i2c_class_init,
882 };
883 
884 static qemu_irq aspeed_2500_i2c_bus_get_irq(AspeedI2CBus *bus)
885 {
886     return bus->controller->irq;
887 }
888 
889 static uint8_t *aspeed_2500_i2c_bus_pool_base(AspeedI2CBus *bus)
890 {
891     return &bus->controller->pool[bus->id * 0x10];
892 }
893 
894 static void aspeed_2500_i2c_class_init(ObjectClass *klass, void *data)
895 {
896     DeviceClass *dc = DEVICE_CLASS(klass);
897     AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass);
898 
899     dc->desc = "ASPEED 2500 I2C Controller";
900 
901     aic->num_busses = 14;
902     aic->reg_size = 0x40;
903     aic->gap = 7;
904     aic->bus_get_irq = aspeed_2500_i2c_bus_get_irq;
905     aic->pool_size = 0x100;
906     aic->pool_base = 0x200;
907     aic->bus_pool_base = aspeed_2500_i2c_bus_pool_base;
908     aic->check_sram = true;
909     aic->has_dma = true;
910 }
911 
912 static const TypeInfo aspeed_2500_i2c_info = {
913     .name = TYPE_ASPEED_2500_I2C,
914     .parent = TYPE_ASPEED_I2C,
915     .class_init = aspeed_2500_i2c_class_init,
916 };
917 
918 static qemu_irq aspeed_2600_i2c_bus_get_irq(AspeedI2CBus *bus)
919 {
920     return bus->irq;
921 }
922 
923 static uint8_t *aspeed_2600_i2c_bus_pool_base(AspeedI2CBus *bus)
924 {
925    return &bus->controller->pool[bus->id * 0x20];
926 }
927 
928 static void aspeed_2600_i2c_class_init(ObjectClass *klass, void *data)
929 {
930     DeviceClass *dc = DEVICE_CLASS(klass);
931     AspeedI2CClass *aic = ASPEED_I2C_CLASS(klass);
932 
933     dc->desc = "ASPEED 2600 I2C Controller";
934 
935     aic->num_busses = 16;
936     aic->reg_size = 0x80;
937     aic->gap = -1; /* no gap */
938     aic->bus_get_irq = aspeed_2600_i2c_bus_get_irq;
939     aic->pool_size = 0x200;
940     aic->pool_base = 0xC00;
941     aic->bus_pool_base = aspeed_2600_i2c_bus_pool_base;
942     aic->has_dma = true;
943 }
944 
945 static const TypeInfo aspeed_2600_i2c_info = {
946     .name = TYPE_ASPEED_2600_I2C,
947     .parent = TYPE_ASPEED_I2C,
948     .class_init = aspeed_2600_i2c_class_init,
949 };
950 
951 static void aspeed_i2c_register_types(void)
952 {
953     type_register_static(&aspeed_i2c_info);
954     type_register_static(&aspeed_2400_i2c_info);
955     type_register_static(&aspeed_2500_i2c_info);
956     type_register_static(&aspeed_2600_i2c_info);
957 }
958 
959 type_init(aspeed_i2c_register_types)
960 
961 
962 I2CBus *aspeed_i2c_get_bus(DeviceState *dev, int busnr)
963 {
964     AspeedI2CState *s = ASPEED_I2C(dev);
965     AspeedI2CClass *aic = ASPEED_I2C_GET_CLASS(s);
966     I2CBus *bus = NULL;
967 
968     if (busnr >= 0 && busnr < aic->num_busses) {
969         bus = s->busses[busnr].bus;
970     }
971 
972     return bus;
973 }
974