1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2017 Hisilicon Limited, All Rights Reserved.
4 * Author: Zhichang Yuan <yuanzhichang@hisilicon.com>
5 * Author: Zou Rongrong <zourongrong@huawei.com>
6 * Author: John Garry <john.garry@huawei.com>
7 */
8
9 #include <linux/acpi.h>
10 #include <linux/console.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13 #include <linux/logic_pio.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_platform.h>
18 #include <linux/pci.h>
19 #include <linux/serial_8250.h>
20 #include <linux/slab.h>
21
22 #define DRV_NAME "hisi-lpc"
23
24 /*
25 * Setting this bit means each IO operation will target a different port
26 * address; 0 means repeated IO operations will use the same port,
27 * such as BT.
28 */
29 #define FG_INCRADDR_LPC 0x02
30
31 struct lpc_cycle_para {
32 unsigned int opflags;
33 unsigned int csize; /* data length of each operation */
34 };
35
36 struct hisi_lpc_dev {
37 spinlock_t cycle_lock;
38 void __iomem *membase;
39 struct logic_pio_hwaddr *io_host;
40 };
41
42 /* The max IO cycle counts supported is four per operation at maximum */
43 #define LPC_MAX_DWIDTH 4
44
45 #define LPC_REG_STARTUP_SIGNAL 0x00
46 #define LPC_REG_STARTUP_SIGNAL_START BIT(0)
47 #define LPC_REG_OP_STATUS 0x04
48 #define LPC_REG_OP_STATUS_IDLE BIT(0)
49 #define LPC_REG_OP_STATUS_FINISHED BIT(1)
50 #define LPC_REG_OP_LEN 0x10 /* LPC cycles count per start */
51 #define LPC_REG_CMD 0x14
52 #define LPC_REG_CMD_OP BIT(0) /* 0: read, 1: write */
53 #define LPC_REG_CMD_SAMEADDR BIT(3)
54 #define LPC_REG_ADDR 0x20 /* target address */
55 #define LPC_REG_WDATA 0x24 /* write FIFO */
56 #define LPC_REG_RDATA 0x28 /* read FIFO */
57
58 /* The minimal nanosecond interval for each query on LPC cycle status */
59 #define LPC_NSEC_PERWAIT 100
60
61 /*
62 * The maximum waiting time is about 128us. It is specific for stream I/O,
63 * such as ins.
64 *
65 * The fastest IO cycle time is about 390ns, but the worst case will wait
66 * for extra 256 lpc clocks, so (256 + 13) * 30ns = 8 us. The maximum burst
67 * cycles is 16. So, the maximum waiting time is about 128us under worst
68 * case.
69 *
70 * Choose 1300 as the maximum.
71 */
72 #define LPC_MAX_WAITCNT 1300
73
74 /* About 10us. This is specific for single IO operations, such as inb */
75 #define LPC_PEROP_WAITCNT 100
76
wait_lpc_idle(unsigned char * mbase,unsigned int waitcnt)77 static int wait_lpc_idle(unsigned char *mbase, unsigned int waitcnt)
78 {
79 u32 status;
80
81 do {
82 status = readl(mbase + LPC_REG_OP_STATUS);
83 if (status & LPC_REG_OP_STATUS_IDLE)
84 return (status & LPC_REG_OP_STATUS_FINISHED) ? 0 : -EIO;
85 ndelay(LPC_NSEC_PERWAIT);
86 } while (--waitcnt);
87
88 return -ETIME;
89 }
90
91 /*
92 * hisi_lpc_target_in - trigger a series of LPC cycles for read operation
93 * @lpcdev: pointer to hisi lpc device
94 * @para: some parameters used to control the lpc I/O operations
95 * @addr: the lpc I/O target port address
96 * @buf: where the read back data is stored
97 * @opcnt: how many I/O operations required, i.e. data width
98 *
99 * Returns 0 on success, non-zero on fail.
100 */
hisi_lpc_target_in(struct hisi_lpc_dev * lpcdev,struct lpc_cycle_para * para,unsigned long addr,unsigned char * buf,unsigned long opcnt)101 static int hisi_lpc_target_in(struct hisi_lpc_dev *lpcdev,
102 struct lpc_cycle_para *para, unsigned long addr,
103 unsigned char *buf, unsigned long opcnt)
104 {
105 unsigned int cmd_word;
106 unsigned int waitcnt;
107 unsigned long flags;
108 int ret;
109
110 if (!buf || !opcnt || !para || !para->csize || !lpcdev)
111 return -EINVAL;
112
113 cmd_word = 0; /* IO mode, Read */
114 waitcnt = LPC_PEROP_WAITCNT;
115 if (!(para->opflags & FG_INCRADDR_LPC)) {
116 cmd_word |= LPC_REG_CMD_SAMEADDR;
117 waitcnt = LPC_MAX_WAITCNT;
118 }
119
120 /* whole operation must be atomic */
121 spin_lock_irqsave(&lpcdev->cycle_lock, flags);
122
123 writel_relaxed(opcnt, lpcdev->membase + LPC_REG_OP_LEN);
124 writel_relaxed(cmd_word, lpcdev->membase + LPC_REG_CMD);
125 writel_relaxed(addr, lpcdev->membase + LPC_REG_ADDR);
126
127 writel(LPC_REG_STARTUP_SIGNAL_START,
128 lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
129
130 /* whether the operation is finished */
131 ret = wait_lpc_idle(lpcdev->membase, waitcnt);
132 if (ret) {
133 spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
134 return ret;
135 }
136
137 readsb(lpcdev->membase + LPC_REG_RDATA, buf, opcnt);
138
139 spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
140
141 return 0;
142 }
143
144 /*
145 * hisi_lpc_target_out - trigger a series of LPC cycles for write operation
146 * @lpcdev: pointer to hisi lpc device
147 * @para: some parameters used to control the lpc I/O operations
148 * @addr: the lpc I/O target port address
149 * @buf: where the data to be written is stored
150 * @opcnt: how many I/O operations required, i.e. data width
151 *
152 * Returns 0 on success, non-zero on fail.
153 */
hisi_lpc_target_out(struct hisi_lpc_dev * lpcdev,struct lpc_cycle_para * para,unsigned long addr,const unsigned char * buf,unsigned long opcnt)154 static int hisi_lpc_target_out(struct hisi_lpc_dev *lpcdev,
155 struct lpc_cycle_para *para, unsigned long addr,
156 const unsigned char *buf, unsigned long opcnt)
157 {
158 unsigned int waitcnt;
159 unsigned long flags;
160 u32 cmd_word;
161 int ret;
162
163 if (!buf || !opcnt || !para || !lpcdev)
164 return -EINVAL;
165
166 /* default is increasing address */
167 cmd_word = LPC_REG_CMD_OP; /* IO mode, write */
168 waitcnt = LPC_PEROP_WAITCNT;
169 if (!(para->opflags & FG_INCRADDR_LPC)) {
170 cmd_word |= LPC_REG_CMD_SAMEADDR;
171 waitcnt = LPC_MAX_WAITCNT;
172 }
173
174 spin_lock_irqsave(&lpcdev->cycle_lock, flags);
175
176 writel_relaxed(opcnt, lpcdev->membase + LPC_REG_OP_LEN);
177 writel_relaxed(cmd_word, lpcdev->membase + LPC_REG_CMD);
178 writel_relaxed(addr, lpcdev->membase + LPC_REG_ADDR);
179
180 writesb(lpcdev->membase + LPC_REG_WDATA, buf, opcnt);
181
182 writel(LPC_REG_STARTUP_SIGNAL_START,
183 lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
184
185 /* whether the operation is finished */
186 ret = wait_lpc_idle(lpcdev->membase, waitcnt);
187
188 spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
189
190 return ret;
191 }
192
hisi_lpc_pio_to_addr(struct hisi_lpc_dev * lpcdev,unsigned long pio)193 static unsigned long hisi_lpc_pio_to_addr(struct hisi_lpc_dev *lpcdev,
194 unsigned long pio)
195 {
196 return pio - lpcdev->io_host->io_start + lpcdev->io_host->hw_start;
197 }
198
199 /*
200 * hisi_lpc_comm_in - input the data in a single operation
201 * @hostdata: pointer to the device information relevant to LPC controller
202 * @pio: the target I/O port address
203 * @dwidth: the data length required to read from the target I/O port
204 *
205 * When success, data is returned. Otherwise, ~0 is returned.
206 */
hisi_lpc_comm_in(void * hostdata,unsigned long pio,size_t dwidth)207 static u32 hisi_lpc_comm_in(void *hostdata, unsigned long pio, size_t dwidth)
208 {
209 struct hisi_lpc_dev *lpcdev = hostdata;
210 struct lpc_cycle_para iopara;
211 unsigned long addr;
212 u32 rd_data = 0;
213 int ret;
214
215 if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
216 return ~0;
217
218 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
219
220 iopara.opflags = FG_INCRADDR_LPC;
221 iopara.csize = dwidth;
222
223 ret = hisi_lpc_target_in(lpcdev, &iopara, addr,
224 (unsigned char *)&rd_data, dwidth);
225 if (ret)
226 return ~0;
227
228 return le32_to_cpu(rd_data);
229 }
230
231 /*
232 * hisi_lpc_comm_out - output the data in a single operation
233 * @hostdata: pointer to the device information relevant to LPC controller
234 * @pio: the target I/O port address
235 * @val: a value to be output from caller, maximum is four bytes
236 * @dwidth: the data width required writing to the target I/O port
237 *
238 * This function corresponds to out(b,w,l) only.
239 */
hisi_lpc_comm_out(void * hostdata,unsigned long pio,u32 val,size_t dwidth)240 static void hisi_lpc_comm_out(void *hostdata, unsigned long pio,
241 u32 val, size_t dwidth)
242 {
243 struct hisi_lpc_dev *lpcdev = hostdata;
244 struct lpc_cycle_para iopara;
245 const unsigned char *buf;
246 unsigned long addr;
247
248 if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
249 return;
250
251 val = cpu_to_le32(val);
252
253 buf = (const unsigned char *)&val;
254 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
255
256 iopara.opflags = FG_INCRADDR_LPC;
257 iopara.csize = dwidth;
258
259 hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth);
260 }
261
262 /*
263 * hisi_lpc_comm_ins - input the data in the buffer in multiple operations
264 * @hostdata: pointer to the device information relevant to LPC controller
265 * @pio: the target I/O port address
266 * @buffer: a buffer where read/input data bytes are stored
267 * @dwidth: the data width required writing to the target I/O port
268 * @count: how many data units whose length is dwidth will be read
269 *
270 * When success, the data read back is stored in buffer pointed by buffer.
271 * Returns 0 on success, -errno otherwise.
272 */
hisi_lpc_comm_ins(void * hostdata,unsigned long pio,void * buffer,size_t dwidth,unsigned int count)273 static u32 hisi_lpc_comm_ins(void *hostdata, unsigned long pio, void *buffer,
274 size_t dwidth, unsigned int count)
275 {
276 struct hisi_lpc_dev *lpcdev = hostdata;
277 unsigned char *buf = buffer;
278 struct lpc_cycle_para iopara;
279 unsigned long addr;
280
281 if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
282 return -EINVAL;
283
284 iopara.opflags = 0;
285 if (dwidth > 1)
286 iopara.opflags |= FG_INCRADDR_LPC;
287 iopara.csize = dwidth;
288
289 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
290
291 do {
292 int ret;
293
294 ret = hisi_lpc_target_in(lpcdev, &iopara, addr, buf, dwidth);
295 if (ret)
296 return ret;
297 buf += dwidth;
298 } while (--count);
299
300 return 0;
301 }
302
303 /*
304 * hisi_lpc_comm_outs - output the data in the buffer in multiple operations
305 * @hostdata: pointer to the device information relevant to LPC controller
306 * @pio: the target I/O port address
307 * @buffer: a buffer where write/output data bytes are stored
308 * @dwidth: the data width required writing to the target I/O port
309 * @count: how many data units whose length is dwidth will be written
310 */
hisi_lpc_comm_outs(void * hostdata,unsigned long pio,const void * buffer,size_t dwidth,unsigned int count)311 static void hisi_lpc_comm_outs(void *hostdata, unsigned long pio,
312 const void *buffer, size_t dwidth,
313 unsigned int count)
314 {
315 struct hisi_lpc_dev *lpcdev = hostdata;
316 struct lpc_cycle_para iopara;
317 const unsigned char *buf = buffer;
318 unsigned long addr;
319
320 if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
321 return;
322
323 iopara.opflags = 0;
324 if (dwidth > 1)
325 iopara.opflags |= FG_INCRADDR_LPC;
326 iopara.csize = dwidth;
327
328 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
329 do {
330 if (hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth))
331 break;
332 buf += dwidth;
333 } while (--count);
334 }
335
336 static const struct logic_pio_host_ops hisi_lpc_ops = {
337 .in = hisi_lpc_comm_in,
338 .out = hisi_lpc_comm_out,
339 .ins = hisi_lpc_comm_ins,
340 .outs = hisi_lpc_comm_outs,
341 };
342
343 #ifdef CONFIG_ACPI
hisi_lpc_acpi_xlat_io_res(struct acpi_device * adev,struct acpi_device * host,struct resource * res)344 static int hisi_lpc_acpi_xlat_io_res(struct acpi_device *adev,
345 struct acpi_device *host,
346 struct resource *res)
347 {
348 unsigned long sys_port;
349 resource_size_t len = resource_size(res);
350
351 sys_port = logic_pio_trans_hwaddr(&host->fwnode, res->start, len);
352 if (sys_port == ~0UL)
353 return -EFAULT;
354
355 res->start = sys_port;
356 res->end = sys_port + len;
357
358 return 0;
359 }
360
361 /*
362 * hisi_lpc_acpi_set_io_res - set the resources for a child
363 * @child: the device node to be updated the I/O resource
364 * @hostdev: the device node associated with host controller
365 * @res: double pointer to be set to the address of translated resources
366 * @num_res: pointer to variable to hold the number of translated resources
367 *
368 * Returns 0 when successful, and a negative value for failure.
369 *
370 * For a given host controller, each child device will have an associated
371 * host-relative address resource. This function will return the translated
372 * logical PIO addresses for each child devices resources.
373 */
hisi_lpc_acpi_set_io_res(struct device * child,struct device * hostdev,const struct resource ** res,int * num_res)374 static int hisi_lpc_acpi_set_io_res(struct device *child,
375 struct device *hostdev,
376 const struct resource **res, int *num_res)
377 {
378 struct acpi_device *adev;
379 struct acpi_device *host;
380 struct resource_entry *rentry;
381 LIST_HEAD(resource_list);
382 struct resource *resources;
383 int count;
384 int i;
385
386 if (!child || !hostdev)
387 return -EINVAL;
388
389 host = to_acpi_device(hostdev);
390 adev = to_acpi_device(child);
391
392 if (!adev->status.present) {
393 dev_dbg(child, "device is not present\n");
394 return -EIO;
395 }
396
397 if (acpi_device_enumerated(adev)) {
398 dev_dbg(child, "has been enumerated\n");
399 return -EIO;
400 }
401
402 /*
403 * The following code segment to retrieve the resources is common to
404 * acpi_create_platform_device(), so consider a common helper function
405 * in future.
406 */
407 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
408 if (count <= 0) {
409 dev_dbg(child, "failed to get resources\n");
410 return count ? count : -EIO;
411 }
412
413 resources = devm_kcalloc(hostdev, count, sizeof(*resources),
414 GFP_KERNEL);
415 if (!resources) {
416 dev_warn(hostdev, "could not allocate memory for %d resources\n",
417 count);
418 acpi_dev_free_resource_list(&resource_list);
419 return -ENOMEM;
420 }
421 count = 0;
422 list_for_each_entry(rentry, &resource_list, node)
423 resources[count++] = *rentry->res;
424
425 acpi_dev_free_resource_list(&resource_list);
426
427 /* translate the I/O resources */
428 for (i = 0; i < count; i++) {
429 int ret;
430
431 if (!(resources[i].flags & IORESOURCE_IO))
432 continue;
433 ret = hisi_lpc_acpi_xlat_io_res(adev, host, &resources[i]);
434 if (ret) {
435 dev_err(child, "translate IO range %pR failed (%d)\n",
436 &resources[i], ret);
437 return ret;
438 }
439 }
440 *res = resources;
441 *num_res = count;
442
443 return 0;
444 }
445
hisi_lpc_acpi_remove_subdev(struct device * dev,void * unused)446 static int hisi_lpc_acpi_remove_subdev(struct device *dev, void *unused)
447 {
448 platform_device_unregister(to_platform_device(dev));
449 return 0;
450 }
451
452 struct hisi_lpc_acpi_cell {
453 const char *hid;
454 const char *name;
455 void *pdata;
456 size_t pdata_size;
457 };
458
459 /*
460 * hisi_lpc_acpi_probe - probe children for ACPI FW
461 * @hostdev: LPC host device pointer
462 *
463 * Returns 0 when successful, and a negative value for failure.
464 *
465 * Create a platform device per child, fixing up the resources
466 * from bus addresses to Logical PIO addresses.
467 *
468 */
hisi_lpc_acpi_probe(struct device * hostdev)469 static int hisi_lpc_acpi_probe(struct device *hostdev)
470 {
471 struct acpi_device *adev = ACPI_COMPANION(hostdev);
472 struct acpi_device *child;
473 int ret;
474
475 /* Only consider the children of the host */
476 list_for_each_entry(child, &adev->children, node) {
477 const char *hid = acpi_device_hid(child);
478 const struct hisi_lpc_acpi_cell *cell;
479 struct platform_device *pdev;
480 const struct resource *res;
481 bool found = false;
482 int num_res;
483
484 ret = hisi_lpc_acpi_set_io_res(&child->dev, &adev->dev, &res,
485 &num_res);
486 if (ret) {
487 dev_warn(hostdev, "set resource fail (%d)\n", ret);
488 goto fail;
489 }
490
491 cell = (struct hisi_lpc_acpi_cell []){
492 /* ipmi */
493 {
494 .hid = "IPI0001",
495 .name = "hisi-lpc-ipmi",
496 },
497 /* 8250-compatible uart */
498 {
499 .hid = "HISI1031",
500 .name = "serial8250",
501 .pdata = (struct plat_serial8250_port []) {
502 {
503 .iobase = res->start,
504 .uartclk = 1843200,
505 .iotype = UPIO_PORT,
506 .flags = UPF_BOOT_AUTOCONF,
507 },
508 {}
509 },
510 .pdata_size = 2 *
511 sizeof(struct plat_serial8250_port),
512 },
513 {}
514 };
515
516 for (; cell && cell->name; cell++) {
517 if (!strcmp(cell->hid, hid)) {
518 found = true;
519 break;
520 }
521 }
522
523 if (!found) {
524 dev_warn(hostdev,
525 "could not find cell for child device (%s)\n",
526 hid);
527 ret = -ENODEV;
528 goto fail;
529 }
530
531 pdev = platform_device_alloc(cell->name, PLATFORM_DEVID_AUTO);
532 if (!pdev) {
533 ret = -ENOMEM;
534 goto fail;
535 }
536
537 pdev->dev.parent = hostdev;
538 ACPI_COMPANION_SET(&pdev->dev, child);
539
540 ret = platform_device_add_resources(pdev, res, num_res);
541 if (ret)
542 goto fail;
543
544 ret = platform_device_add_data(pdev, cell->pdata,
545 cell->pdata_size);
546 if (ret)
547 goto fail;
548
549 ret = platform_device_add(pdev);
550 if (ret)
551 goto fail;
552
553 acpi_device_set_enumerated(child);
554 }
555
556 return 0;
557
558 fail:
559 device_for_each_child(hostdev, NULL,
560 hisi_lpc_acpi_remove_subdev);
561 return ret;
562 }
563
564 static const struct acpi_device_id hisi_lpc_acpi_match[] = {
565 {"HISI0191"},
566 {}
567 };
568 #else
hisi_lpc_acpi_probe(struct device * dev)569 static int hisi_lpc_acpi_probe(struct device *dev)
570 {
571 return -ENODEV;
572 }
573 #endif // CONFIG_ACPI
574
575 /*
576 * hisi_lpc_probe - the probe callback function for hisi lpc host,
577 * will finish all the initialization.
578 * @pdev: the platform device corresponding to hisi lpc host
579 *
580 * Returns 0 on success, non-zero on fail.
581 */
hisi_lpc_probe(struct platform_device * pdev)582 static int hisi_lpc_probe(struct platform_device *pdev)
583 {
584 struct device *dev = &pdev->dev;
585 struct acpi_device *acpi_device = ACPI_COMPANION(dev);
586 struct logic_pio_hwaddr *range;
587 struct hisi_lpc_dev *lpcdev;
588 resource_size_t io_end;
589 struct resource *res;
590 int ret;
591
592 lpcdev = devm_kzalloc(dev, sizeof(*lpcdev), GFP_KERNEL);
593 if (!lpcdev)
594 return -ENOMEM;
595
596 spin_lock_init(&lpcdev->cycle_lock);
597
598 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
599 lpcdev->membase = devm_ioremap_resource(dev, res);
600 if (IS_ERR(lpcdev->membase))
601 return PTR_ERR(lpcdev->membase);
602
603 range = devm_kzalloc(dev, sizeof(*range), GFP_KERNEL);
604 if (!range)
605 return -ENOMEM;
606
607 range->fwnode = dev->fwnode;
608 range->flags = LOGIC_PIO_INDIRECT;
609 range->size = PIO_INDIRECT_SIZE;
610
611 ret = logic_pio_register_range(range);
612 if (ret) {
613 dev_err(dev, "register IO range failed (%d)!\n", ret);
614 return ret;
615 }
616 lpcdev->io_host = range;
617
618 /* register the LPC host PIO resources */
619 if (acpi_device)
620 ret = hisi_lpc_acpi_probe(dev);
621 else
622 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
623 if (ret)
624 return ret;
625
626 lpcdev->io_host->hostdata = lpcdev;
627 lpcdev->io_host->ops = &hisi_lpc_ops;
628
629 io_end = lpcdev->io_host->io_start + lpcdev->io_host->size;
630 dev_info(dev, "registered range [%pa - %pa]\n",
631 &lpcdev->io_host->io_start, &io_end);
632
633 return ret;
634 }
635
636 static const struct of_device_id hisi_lpc_of_match[] = {
637 { .compatible = "hisilicon,hip06-lpc", },
638 { .compatible = "hisilicon,hip07-lpc", },
639 {}
640 };
641
642 static struct platform_driver hisi_lpc_driver = {
643 .driver = {
644 .name = DRV_NAME,
645 .of_match_table = hisi_lpc_of_match,
646 .acpi_match_table = ACPI_PTR(hisi_lpc_acpi_match),
647 },
648 .probe = hisi_lpc_probe,
649 };
650 builtin_platform_driver(hisi_lpc_driver);
651
