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12#include <acpi/pcc.h>
13#include <linux/acpi.h>
14#include <linux/dma-mapping.h>
15#include <linux/i2c.h>
16#include <linux/interrupt.h>
17#include <linux/io.h>
18#include <linux/mailbox_client.h>
19#include <linux/module.h>
20#include <linux/of.h>
21#include <linux/platform_device.h>
22#include <linux/version.h>
23
24#define MAILBOX_OP_TIMEOUT 1000
25#define MAILBOX_I2C_INDEX 0
26#define SLIMPRO_IIC_BUS 1
27
28#define SMBUS_CMD_LEN 1
29#define BYTE_DATA 1
30#define WORD_DATA 2
31#define BLOCK_DATA 3
32
33#define SLIMPRO_IIC_I2C_PROTOCOL 0
34#define SLIMPRO_IIC_SMB_PROTOCOL 1
35
36#define SLIMPRO_IIC_READ 0
37#define SLIMPRO_IIC_WRITE 1
38
39#define IIC_SMB_WITHOUT_DATA_LEN 0
40#define IIC_SMB_WITH_DATA_LEN 1
41
42#define SLIMPRO_DEBUG_MSG 0
43#define SLIMPRO_MSG_TYPE_SHIFT 28
44#define SLIMPRO_DBG_SUBTYPE_I2C1READ 4
45#define SLIMPRO_DBGMSG_TYPE_SHIFT 24
46#define SLIMPRO_DBGMSG_TYPE_MASK 0x0F000000U
47#define SLIMPRO_IIC_DEV_SHIFT 23
48#define SLIMPRO_IIC_DEV_MASK 0x00800000U
49#define SLIMPRO_IIC_DEVID_SHIFT 13
50#define SLIMPRO_IIC_DEVID_MASK 0x007FE000U
51#define SLIMPRO_IIC_RW_SHIFT 12
52#define SLIMPRO_IIC_RW_MASK 0x00001000U
53#define SLIMPRO_IIC_PROTO_SHIFT 11
54#define SLIMPRO_IIC_PROTO_MASK 0x00000800U
55#define SLIMPRO_IIC_ADDRLEN_SHIFT 8
56#define SLIMPRO_IIC_ADDRLEN_MASK 0x00000700U
57#define SLIMPRO_IIC_DATALEN_SHIFT 0
58#define SLIMPRO_IIC_DATALEN_MASK 0x000000FFU
59
60
61
62
63
64
65
66
67
68
69
70#define SLIMPRO_IIC_ENCODE_MSG(dev, chip, op, proto, addrlen, datalen) \
71 ((SLIMPRO_DEBUG_MSG << SLIMPRO_MSG_TYPE_SHIFT) | \
72 ((SLIMPRO_DBG_SUBTYPE_I2C1READ << SLIMPRO_DBGMSG_TYPE_SHIFT) & \
73 SLIMPRO_DBGMSG_TYPE_MASK) | \
74 ((dev << SLIMPRO_IIC_DEV_SHIFT) & SLIMPRO_IIC_DEV_MASK) | \
75 ((chip << SLIMPRO_IIC_DEVID_SHIFT) & SLIMPRO_IIC_DEVID_MASK) | \
76 ((op << SLIMPRO_IIC_RW_SHIFT) & SLIMPRO_IIC_RW_MASK) | \
77 ((proto << SLIMPRO_IIC_PROTO_SHIFT) & SLIMPRO_IIC_PROTO_MASK) | \
78 ((addrlen << SLIMPRO_IIC_ADDRLEN_SHIFT) & SLIMPRO_IIC_ADDRLEN_MASK) | \
79 ((datalen << SLIMPRO_IIC_DATALEN_SHIFT) & SLIMPRO_IIC_DATALEN_MASK))
80
81#define SLIMPRO_MSG_TYPE(v) (((v) & 0xF0000000) >> 28)
82
83
84
85
86#define SLIMPRO_IIC_ENCODE_FLAG_BUFADDR 0x80000000
87#define SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(a) ((u32) (((a) << 30) \
88 & 0x40000000))
89#define SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(a) ((u32) (((a) >> 12) \
90 & 0x3FF00000))
91#define SLIMPRO_IIC_ENCODE_ADDR(a) ((a) & 0x000FFFFF)
92
93#define SLIMPRO_IIC_MSG_DWORD_COUNT 3
94
95
96#define PCC_SIGNATURE 0x50424300
97#define PCC_STS_CMD_COMPLETE BIT(0)
98#define PCC_STS_SCI_DOORBELL BIT(1)
99#define PCC_STS_ERR BIT(2)
100#define PCC_STS_PLAT_NOTIFY BIT(3)
101#define PCC_CMD_GENERATE_DB_INT BIT(15)
102
103struct slimpro_i2c_dev {
104 struct i2c_adapter adapter;
105 struct device *dev;
106 struct mbox_chan *mbox_chan;
107 struct mbox_client mbox_client;
108 int mbox_idx;
109 struct completion rd_complete;
110 u8 dma_buffer[I2C_SMBUS_BLOCK_MAX + 1];
111 u32 *resp_msg;
112 phys_addr_t comm_base_addr;
113 void *pcc_comm_addr;
114};
115
116#define to_slimpro_i2c_dev(cl) \
117 container_of(cl, struct slimpro_i2c_dev, mbox_client)
118
119enum slimpro_i2c_version {
120 XGENE_SLIMPRO_I2C_V1 = 0,
121 XGENE_SLIMPRO_I2C_V2 = 1,
122};
123
124
125
126
127static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask)
128{
129 u16 ret, val;
130
131 val = le16_to_cpu(READ_ONCE(*addr));
132 ret = val & mask;
133 val &= ~mask;
134 WRITE_ONCE(*addr, cpu_to_le16(val));
135
136 return ret;
137}
138
139static void slimpro_i2c_rx_cb(struct mbox_client *cl, void *mssg)
140{
141 struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
142
143
144
145
146
147
148
149 if (ctx->resp_msg)
150 *ctx->resp_msg = ((u32 *)mssg)[1];
151
152 if (ctx->mbox_client.tx_block)
153 complete(&ctx->rd_complete);
154}
155
156static void slimpro_i2c_pcc_rx_cb(struct mbox_client *cl, void *msg)
157{
158 struct slimpro_i2c_dev *ctx = to_slimpro_i2c_dev(cl);
159 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
160
161
162 if (!xgene_word_tst_and_clr(&generic_comm_base->status,
163 PCC_STS_SCI_DOORBELL))
164 return;
165
166 if (xgene_word_tst_and_clr(&generic_comm_base->status,
167 PCC_STS_CMD_COMPLETE)) {
168 msg = generic_comm_base + 1;
169
170
171 if (ctx->resp_msg)
172 *ctx->resp_msg = ((u32 *)msg)[1];
173
174 complete(&ctx->rd_complete);
175 }
176}
177
178static void slimpro_i2c_pcc_tx_prepare(struct slimpro_i2c_dev *ctx, u32 *msg)
179{
180 struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr;
181 u32 *ptr = (void *)(generic_comm_base + 1);
182 u16 status;
183 int i;
184
185 WRITE_ONCE(generic_comm_base->signature,
186 cpu_to_le32(PCC_SIGNATURE | ctx->mbox_idx));
187
188 WRITE_ONCE(generic_comm_base->command,
189 cpu_to_le16(SLIMPRO_MSG_TYPE(msg[0]) | PCC_CMD_GENERATE_DB_INT));
190
191 status = le16_to_cpu(READ_ONCE(generic_comm_base->status));
192 status &= ~PCC_STS_CMD_COMPLETE;
193 WRITE_ONCE(generic_comm_base->status, cpu_to_le16(status));
194
195
196 for (i = 0; i < SLIMPRO_IIC_MSG_DWORD_COUNT; i++)
197 WRITE_ONCE(ptr[i], cpu_to_le32(msg[i]));
198}
199
200static int start_i2c_msg_xfer(struct slimpro_i2c_dev *ctx)
201{
202 if (ctx->mbox_client.tx_block || !acpi_disabled) {
203 if (!wait_for_completion_timeout(&ctx->rd_complete,
204 msecs_to_jiffies(MAILBOX_OP_TIMEOUT)))
205 return -ETIMEDOUT;
206 }
207
208
209 if (*ctx->resp_msg == 0xffffffff)
210 return -ENODEV;
211
212 return 0;
213}
214
215static int slimpro_i2c_send_msg(struct slimpro_i2c_dev *ctx,
216 u32 *msg,
217 u32 *data)
218{
219 int rc;
220
221 ctx->resp_msg = data;
222
223 if (!acpi_disabled) {
224 reinit_completion(&ctx->rd_complete);
225 slimpro_i2c_pcc_tx_prepare(ctx, msg);
226 }
227
228 rc = mbox_send_message(ctx->mbox_chan, msg);
229 if (rc < 0)
230 goto err;
231
232 rc = start_i2c_msg_xfer(ctx);
233
234err:
235 if (!acpi_disabled)
236 mbox_chan_txdone(ctx->mbox_chan, 0);
237
238 ctx->resp_msg = NULL;
239
240 return rc;
241}
242
243static int slimpro_i2c_rd(struct slimpro_i2c_dev *ctx, u32 chip,
244 u32 addr, u32 addrlen, u32 protocol,
245 u32 readlen, u32 *data)
246{
247 u32 msg[3];
248
249 msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
250 SLIMPRO_IIC_READ, protocol, addrlen, readlen);
251 msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
252 msg[2] = 0;
253
254 return slimpro_i2c_send_msg(ctx, msg, data);
255}
256
257static int slimpro_i2c_wr(struct slimpro_i2c_dev *ctx, u32 chip,
258 u32 addr, u32 addrlen, u32 protocol, u32 writelen,
259 u32 data)
260{
261 u32 msg[3];
262
263 msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip,
264 SLIMPRO_IIC_WRITE, protocol, addrlen, writelen);
265 msg[1] = SLIMPRO_IIC_ENCODE_ADDR(addr);
266 msg[2] = data;
267
268 return slimpro_i2c_send_msg(ctx, msg, msg);
269}
270
271static int slimpro_i2c_blkrd(struct slimpro_i2c_dev *ctx, u32 chip, u32 addr,
272 u32 addrlen, u32 protocol, u32 readlen,
273 u32 with_data_len, void *data)
274{
275 dma_addr_t paddr;
276 u32 msg[3];
277 int rc;
278
279 paddr = dma_map_single(ctx->dev, ctx->dma_buffer, readlen, DMA_FROM_DEVICE);
280 if (dma_mapping_error(ctx->dev, paddr)) {
281 dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
282 ctx->dma_buffer);
283 return -ENOMEM;
284 }
285
286 msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_READ,
287 protocol, addrlen, readlen);
288 msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
289 SLIMPRO_IIC_ENCODE_FLAG_WITH_DATA_LEN(with_data_len) |
290 SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
291 SLIMPRO_IIC_ENCODE_ADDR(addr);
292 msg[2] = (u32)paddr;
293
294 rc = slimpro_i2c_send_msg(ctx, msg, msg);
295
296
297 memcpy(data, ctx->dma_buffer, readlen);
298
299 dma_unmap_single(ctx->dev, paddr, readlen, DMA_FROM_DEVICE);
300 return rc;
301}
302
303static int slimpro_i2c_blkwr(struct slimpro_i2c_dev *ctx, u32 chip,
304 u32 addr, u32 addrlen, u32 protocol, u32 writelen,
305 void *data)
306{
307 dma_addr_t paddr;
308 u32 msg[3];
309 int rc;
310
311 memcpy(ctx->dma_buffer, data, writelen);
312 paddr = dma_map_single(ctx->dev, ctx->dma_buffer, writelen,
313 DMA_TO_DEVICE);
314 if (dma_mapping_error(ctx->dev, paddr)) {
315 dev_err(&ctx->adapter.dev, "Error in mapping dma buffer %p\n",
316 ctx->dma_buffer);
317 return -ENOMEM;
318 }
319
320 msg[0] = SLIMPRO_IIC_ENCODE_MSG(SLIMPRO_IIC_BUS, chip, SLIMPRO_IIC_WRITE,
321 protocol, addrlen, writelen);
322 msg[1] = SLIMPRO_IIC_ENCODE_FLAG_BUFADDR |
323 SLIMPRO_IIC_ENCODE_UPPER_BUFADDR(paddr) |
324 SLIMPRO_IIC_ENCODE_ADDR(addr);
325 msg[2] = (u32)paddr;
326
327 if (ctx->mbox_client.tx_block)
328 reinit_completion(&ctx->rd_complete);
329
330 rc = slimpro_i2c_send_msg(ctx, msg, msg);
331
332 dma_unmap_single(ctx->dev, paddr, writelen, DMA_TO_DEVICE);
333 return rc;
334}
335
336static int xgene_slimpro_i2c_xfer(struct i2c_adapter *adap, u16 addr,
337 unsigned short flags, char read_write,
338 u8 command, int size,
339 union i2c_smbus_data *data)
340{
341 struct slimpro_i2c_dev *ctx = i2c_get_adapdata(adap);
342 int ret = -EOPNOTSUPP;
343 u32 val;
344
345 switch (size) {
346 case I2C_SMBUS_BYTE:
347 if (read_write == I2C_SMBUS_READ) {
348 ret = slimpro_i2c_rd(ctx, addr, 0, 0,
349 SLIMPRO_IIC_SMB_PROTOCOL,
350 BYTE_DATA, &val);
351 data->byte = val;
352 } else {
353 ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
354 SLIMPRO_IIC_SMB_PROTOCOL,
355 0, 0);
356 }
357 break;
358 case I2C_SMBUS_BYTE_DATA:
359 if (read_write == I2C_SMBUS_READ) {
360 ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
361 SLIMPRO_IIC_SMB_PROTOCOL,
362 BYTE_DATA, &val);
363 data->byte = val;
364 } else {
365 val = data->byte;
366 ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
367 SLIMPRO_IIC_SMB_PROTOCOL,
368 BYTE_DATA, val);
369 }
370 break;
371 case I2C_SMBUS_WORD_DATA:
372 if (read_write == I2C_SMBUS_READ) {
373 ret = slimpro_i2c_rd(ctx, addr, command, SMBUS_CMD_LEN,
374 SLIMPRO_IIC_SMB_PROTOCOL,
375 WORD_DATA, &val);
376 data->word = val;
377 } else {
378 val = data->word;
379 ret = slimpro_i2c_wr(ctx, addr, command, SMBUS_CMD_LEN,
380 SLIMPRO_IIC_SMB_PROTOCOL,
381 WORD_DATA, val);
382 }
383 break;
384 case I2C_SMBUS_BLOCK_DATA:
385 if (read_write == I2C_SMBUS_READ) {
386 ret = slimpro_i2c_blkrd(ctx, addr, command,
387 SMBUS_CMD_LEN,
388 SLIMPRO_IIC_SMB_PROTOCOL,
389 I2C_SMBUS_BLOCK_MAX + 1,
390 IIC_SMB_WITH_DATA_LEN,
391 &data->block[0]);
392
393 } else {
394 ret = slimpro_i2c_blkwr(ctx, addr, command,
395 SMBUS_CMD_LEN,
396 SLIMPRO_IIC_SMB_PROTOCOL,
397 data->block[0] + 1,
398 &data->block[0]);
399 }
400 break;
401 case I2C_SMBUS_I2C_BLOCK_DATA:
402 if (read_write == I2C_SMBUS_READ) {
403 ret = slimpro_i2c_blkrd(ctx, addr,
404 command,
405 SMBUS_CMD_LEN,
406 SLIMPRO_IIC_I2C_PROTOCOL,
407 I2C_SMBUS_BLOCK_MAX,
408 IIC_SMB_WITHOUT_DATA_LEN,
409 &data->block[1]);
410 } else {
411 ret = slimpro_i2c_blkwr(ctx, addr, command,
412 SMBUS_CMD_LEN,
413 SLIMPRO_IIC_I2C_PROTOCOL,
414 data->block[0],
415 &data->block[1]);
416 }
417 break;
418 default:
419 break;
420 }
421 return ret;
422}
423
424
425
426
427static u32 xgene_slimpro_i2c_func(struct i2c_adapter *adapter)
428{
429 return I2C_FUNC_SMBUS_BYTE |
430 I2C_FUNC_SMBUS_BYTE_DATA |
431 I2C_FUNC_SMBUS_WORD_DATA |
432 I2C_FUNC_SMBUS_BLOCK_DATA |
433 I2C_FUNC_SMBUS_I2C_BLOCK;
434}
435
436static const struct i2c_algorithm xgene_slimpro_i2c_algorithm = {
437 .smbus_xfer = xgene_slimpro_i2c_xfer,
438 .functionality = xgene_slimpro_i2c_func,
439};
440
441static int xgene_slimpro_i2c_probe(struct platform_device *pdev)
442{
443 struct slimpro_i2c_dev *ctx;
444 struct i2c_adapter *adapter;
445 struct mbox_client *cl;
446 int rc;
447
448 ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
449 if (!ctx)
450 return -ENOMEM;
451
452 ctx->dev = &pdev->dev;
453 platform_set_drvdata(pdev, ctx);
454 cl = &ctx->mbox_client;
455
456
457 cl->dev = &pdev->dev;
458 init_completion(&ctx->rd_complete);
459 cl->tx_tout = MAILBOX_OP_TIMEOUT;
460 cl->knows_txdone = false;
461 if (acpi_disabled) {
462 cl->tx_block = true;
463 cl->rx_callback = slimpro_i2c_rx_cb;
464 ctx->mbox_chan = mbox_request_channel(cl, MAILBOX_I2C_INDEX);
465 if (IS_ERR(ctx->mbox_chan)) {
466 dev_err(&pdev->dev, "i2c mailbox channel request failed\n");
467 return PTR_ERR(ctx->mbox_chan);
468 }
469 } else {
470 struct acpi_pcct_hw_reduced *cppc_ss;
471 const struct acpi_device_id *acpi_id;
472 int version = XGENE_SLIMPRO_I2C_V1;
473
474 acpi_id = acpi_match_device(pdev->dev.driver->acpi_match_table,
475 &pdev->dev);
476 if (!acpi_id)
477 return -EINVAL;
478
479 version = (int)acpi_id->driver_data;
480
481 if (device_property_read_u32(&pdev->dev, "pcc-channel",
482 &ctx->mbox_idx))
483 ctx->mbox_idx = MAILBOX_I2C_INDEX;
484
485 cl->tx_block = false;
486 cl->rx_callback = slimpro_i2c_pcc_rx_cb;
487 ctx->mbox_chan = pcc_mbox_request_channel(cl, ctx->mbox_idx);
488 if (IS_ERR(ctx->mbox_chan)) {
489 dev_err(&pdev->dev, "PCC mailbox channel request failed\n");
490 return PTR_ERR(ctx->mbox_chan);
491 }
492
493
494
495
496
497
498
499 cppc_ss = ctx->mbox_chan->con_priv;
500 if (!cppc_ss) {
501 dev_err(&pdev->dev, "PPC subspace not found\n");
502 rc = -ENOENT;
503 goto mbox_err;
504 }
505
506 if (!ctx->mbox_chan->mbox->txdone_irq) {
507 dev_err(&pdev->dev, "PCC IRQ not supported\n");
508 rc = -ENOENT;
509 goto mbox_err;
510 }
511
512
513
514
515
516 ctx->comm_base_addr = cppc_ss->base_address;
517 if (ctx->comm_base_addr) {
518 if (version == XGENE_SLIMPRO_I2C_V2)
519 ctx->pcc_comm_addr = memremap(
520 ctx->comm_base_addr,
521 cppc_ss->length,
522 MEMREMAP_WT);
523 else
524 ctx->pcc_comm_addr = memremap(
525 ctx->comm_base_addr,
526 cppc_ss->length,
527 MEMREMAP_WB);
528 } else {
529 dev_err(&pdev->dev, "Failed to get PCC comm region\n");
530 rc = -ENOENT;
531 goto mbox_err;
532 }
533
534 if (!ctx->pcc_comm_addr) {
535 dev_err(&pdev->dev,
536 "Failed to ioremap PCC comm region\n");
537 rc = -ENOMEM;
538 goto mbox_err;
539 }
540 }
541 rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
542 if (rc)
543 dev_warn(&pdev->dev, "Unable to set dma mask\n");
544
545
546 adapter = &ctx->adapter;
547 snprintf(adapter->name, sizeof(adapter->name), "MAILBOX I2C");
548 adapter->algo = &xgene_slimpro_i2c_algorithm;
549 adapter->class = I2C_CLASS_HWMON;
550 adapter->dev.parent = &pdev->dev;
551 adapter->dev.of_node = pdev->dev.of_node;
552 ACPI_COMPANION_SET(&adapter->dev, ACPI_COMPANION(&pdev->dev));
553 i2c_set_adapdata(adapter, ctx);
554 rc = i2c_add_adapter(adapter);
555 if (rc)
556 goto mbox_err;
557
558 dev_info(&pdev->dev, "Mailbox I2C Adapter registered\n");
559 return 0;
560
561mbox_err:
562 if (acpi_disabled)
563 mbox_free_channel(ctx->mbox_chan);
564 else
565 pcc_mbox_free_channel(ctx->mbox_chan);
566
567 return rc;
568}
569
570static int xgene_slimpro_i2c_remove(struct platform_device *pdev)
571{
572 struct slimpro_i2c_dev *ctx = platform_get_drvdata(pdev);
573
574 i2c_del_adapter(&ctx->adapter);
575
576 if (acpi_disabled)
577 mbox_free_channel(ctx->mbox_chan);
578 else
579 pcc_mbox_free_channel(ctx->mbox_chan);
580
581 return 0;
582}
583
584static const struct of_device_id xgene_slimpro_i2c_dt_ids[] = {
585 {.compatible = "apm,xgene-slimpro-i2c" },
586 {},
587};
588MODULE_DEVICE_TABLE(of, xgene_slimpro_i2c_dt_ids);
589
590#ifdef CONFIG_ACPI
591static const struct acpi_device_id xgene_slimpro_i2c_acpi_ids[] = {
592 {"APMC0D40", XGENE_SLIMPRO_I2C_V1},
593 {"APMC0D8B", XGENE_SLIMPRO_I2C_V2},
594 {}
595};
596MODULE_DEVICE_TABLE(acpi, xgene_slimpro_i2c_acpi_ids);
597#endif
598
599static struct platform_driver xgene_slimpro_i2c_driver = {
600 .probe = xgene_slimpro_i2c_probe,
601 .remove = xgene_slimpro_i2c_remove,
602 .driver = {
603 .name = "xgene-slimpro-i2c",
604 .of_match_table = of_match_ptr(xgene_slimpro_i2c_dt_ids),
605 .acpi_match_table = ACPI_PTR(xgene_slimpro_i2c_acpi_ids)
606 },
607};
608
609module_platform_driver(xgene_slimpro_i2c_driver);
610
611MODULE_DESCRIPTION("APM X-Gene SLIMpro I2C driver");
612MODULE_AUTHOR("Feng Kan <fkan@apm.com>");
613MODULE_AUTHOR("Hieu Le <hnle@apm.com>");
614MODULE_LICENSE("GPL");
615
