gpio: rcar: Fix runtime PM imbalance on error
[linux/fpc-iii.git] / drivers / bus / hisi_lpc.c
blob378f5d62a991271cef7a1ac21db7e689b165c496
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 */
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>
22 #define DRV_NAME "hisi-lpc"
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.
29 #define FG_INCRADDR_LPC 0x02
31 struct lpc_cycle_para {
32 unsigned int opflags;
33 unsigned int csize; /* data length of each operation */
36 struct hisi_lpc_dev {
37 spinlock_t cycle_lock;
38 void __iomem *membase;
39 struct logic_pio_hwaddr *io_host;
42 /* The max IO cycle counts supported is four per operation at maximum */
43 #define LPC_MAX_DWIDTH 4
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 */
58 /* The minimal nanosecond interval for each query on LPC cycle status */
59 #define LPC_NSEC_PERWAIT 100
62 * The maximum waiting time is about 128us. It is specific for stream I/O,
63 * such as ins.
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.
70 * Choose 1300 as the maximum.
72 #define LPC_MAX_WAITCNT 1300
74 /* About 10us. This is specific for single IO operations, such as inb */
75 #define LPC_PEROP_WAITCNT 100
77 static int wait_lpc_idle(void __iomem *mbase, unsigned int waitcnt)
79 u32 status;
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);
88 return -ETIME;
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
99 * Returns 0 on success, non-zero on fail.
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)
105 unsigned int cmd_word;
106 unsigned int waitcnt;
107 unsigned long flags;
108 int ret;
110 if (!buf || !opcnt || !para || !para->csize || !lpcdev)
111 return -EINVAL;
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;
120 /* whole operation must be atomic */
121 spin_lock_irqsave(&lpcdev->cycle_lock, flags);
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);
127 writel(LPC_REG_STARTUP_SIGNAL_START,
128 lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
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;
137 readsb(lpcdev->membase + LPC_REG_RDATA, buf, opcnt);
139 spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
141 return 0;
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
152 * Returns 0 on success, non-zero on fail.
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)
158 unsigned int waitcnt;
159 unsigned long flags;
160 u32 cmd_word;
161 int ret;
163 if (!buf || !opcnt || !para || !lpcdev)
164 return -EINVAL;
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;
174 spin_lock_irqsave(&lpcdev->cycle_lock, flags);
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);
180 writesb(lpcdev->membase + LPC_REG_WDATA, buf, opcnt);
182 writel(LPC_REG_STARTUP_SIGNAL_START,
183 lpcdev->membase + LPC_REG_STARTUP_SIGNAL);
185 /* whether the operation is finished */
186 ret = wait_lpc_idle(lpcdev->membase, waitcnt);
188 spin_unlock_irqrestore(&lpcdev->cycle_lock, flags);
190 return ret;
193 static unsigned long hisi_lpc_pio_to_addr(struct hisi_lpc_dev *lpcdev,
194 unsigned long pio)
196 return pio - lpcdev->io_host->io_start + lpcdev->io_host->hw_start;
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
205 * When success, data is returned. Otherwise, ~0 is returned.
207 static u32 hisi_lpc_comm_in(void *hostdata, unsigned long pio, size_t dwidth)
209 struct hisi_lpc_dev *lpcdev = hostdata;
210 struct lpc_cycle_para iopara;
211 unsigned long addr;
212 __le32 rd_data = 0;
213 int ret;
215 if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
216 return ~0;
218 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
220 iopara.opflags = FG_INCRADDR_LPC;
221 iopara.csize = dwidth;
223 ret = hisi_lpc_target_in(lpcdev, &iopara, addr,
224 (unsigned char *)&rd_data, dwidth);
225 if (ret)
226 return ~0;
228 return le32_to_cpu(rd_data);
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
238 * This function corresponds to out(b,w,l) only.
240 static void hisi_lpc_comm_out(void *hostdata, unsigned long pio,
241 u32 val, size_t dwidth)
243 struct hisi_lpc_dev *lpcdev = hostdata;
244 struct lpc_cycle_para iopara;
245 const unsigned char *buf;
246 unsigned long addr;
247 __le32 _val = cpu_to_le32(val);
249 if (!lpcdev || !dwidth || dwidth > LPC_MAX_DWIDTH)
250 return;
252 buf = (const unsigned char *)&_val;
253 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
255 iopara.opflags = FG_INCRADDR_LPC;
256 iopara.csize = dwidth;
258 hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth);
262 * hisi_lpc_comm_ins - input the data in the buffer in multiple operations
263 * @hostdata: pointer to the device information relevant to LPC controller
264 * @pio: the target I/O port address
265 * @buffer: a buffer where read/input data bytes are stored
266 * @dwidth: the data width required writing to the target I/O port
267 * @count: how many data units whose length is dwidth will be read
269 * When success, the data read back is stored in buffer pointed by buffer.
270 * Returns 0 on success, -errno otherwise.
272 static u32 hisi_lpc_comm_ins(void *hostdata, unsigned long pio, void *buffer,
273 size_t dwidth, unsigned int count)
275 struct hisi_lpc_dev *lpcdev = hostdata;
276 unsigned char *buf = buffer;
277 struct lpc_cycle_para iopara;
278 unsigned long addr;
280 if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
281 return -EINVAL;
283 iopara.opflags = 0;
284 if (dwidth > 1)
285 iopara.opflags |= FG_INCRADDR_LPC;
286 iopara.csize = dwidth;
288 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
290 do {
291 int ret;
293 ret = hisi_lpc_target_in(lpcdev, &iopara, addr, buf, dwidth);
294 if (ret)
295 return ret;
296 buf += dwidth;
297 } while (--count);
299 return 0;
303 * hisi_lpc_comm_outs - output the data in the buffer in multiple operations
304 * @hostdata: pointer to the device information relevant to LPC controller
305 * @pio: the target I/O port address
306 * @buffer: a buffer where write/output data bytes are stored
307 * @dwidth: the data width required writing to the target I/O port
308 * @count: how many data units whose length is dwidth will be written
310 static void hisi_lpc_comm_outs(void *hostdata, unsigned long pio,
311 const void *buffer, size_t dwidth,
312 unsigned int count)
314 struct hisi_lpc_dev *lpcdev = hostdata;
315 struct lpc_cycle_para iopara;
316 const unsigned char *buf = buffer;
317 unsigned long addr;
319 if (!lpcdev || !buf || !count || !dwidth || dwidth > LPC_MAX_DWIDTH)
320 return;
322 iopara.opflags = 0;
323 if (dwidth > 1)
324 iopara.opflags |= FG_INCRADDR_LPC;
325 iopara.csize = dwidth;
327 addr = hisi_lpc_pio_to_addr(lpcdev, pio);
328 do {
329 if (hisi_lpc_target_out(lpcdev, &iopara, addr, buf, dwidth))
330 break;
331 buf += dwidth;
332 } while (--count);
335 static const struct logic_pio_host_ops hisi_lpc_ops = {
336 .in = hisi_lpc_comm_in,
337 .out = hisi_lpc_comm_out,
338 .ins = hisi_lpc_comm_ins,
339 .outs = hisi_lpc_comm_outs,
342 #ifdef CONFIG_ACPI
343 static int hisi_lpc_acpi_xlat_io_res(struct acpi_device *adev,
344 struct acpi_device *host,
345 struct resource *res)
347 unsigned long sys_port;
348 resource_size_t len = resource_size(res);
350 sys_port = logic_pio_trans_hwaddr(&host->fwnode, res->start, len);
351 if (sys_port == ~0UL)
352 return -EFAULT;
354 res->start = sys_port;
355 res->end = sys_port + len;
357 return 0;
361 * Released firmware describes the IO port max address as 0x3fff, which is
362 * the max host bus address. Fixup to a proper range. This will probably
363 * never be fixed in firmware.
365 static void hisi_lpc_acpi_fixup_child_resource(struct device *hostdev,
366 struct resource *r)
368 if (r->end != 0x3fff)
369 return;
371 if (r->start == 0xe4)
372 r->end = 0xe4 + 0x04 - 1;
373 else if (r->start == 0x2f8)
374 r->end = 0x2f8 + 0x08 - 1;
375 else
376 dev_warn(hostdev, "unrecognised resource %pR to fixup, ignoring\n",
381 * hisi_lpc_acpi_set_io_res - set the resources for a child
382 * @child: the device node to be updated the I/O resource
383 * @hostdev: the device node associated with host controller
384 * @res: double pointer to be set to the address of translated resources
385 * @num_res: pointer to variable to hold the number of translated resources
387 * Returns 0 when successful, and a negative value for failure.
389 * For a given host controller, each child device will have an associated
390 * host-relative address resource. This function will return the translated
391 * logical PIO addresses for each child devices resources.
393 static int hisi_lpc_acpi_set_io_res(struct device *child,
394 struct device *hostdev,
395 const struct resource **res, int *num_res)
397 struct acpi_device *adev;
398 struct acpi_device *host;
399 struct resource_entry *rentry;
400 LIST_HEAD(resource_list);
401 struct resource *resources;
402 int count;
403 int i;
405 if (!child || !hostdev)
406 return -EINVAL;
408 host = to_acpi_device(hostdev);
409 adev = to_acpi_device(child);
411 if (!adev->status.present) {
412 dev_dbg(child, "device is not present\n");
413 return -EIO;
416 if (acpi_device_enumerated(adev)) {
417 dev_dbg(child, "has been enumerated\n");
418 return -EIO;
422 * The following code segment to retrieve the resources is common to
423 * acpi_create_platform_device(), so consider a common helper function
424 * in future.
426 count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
427 if (count <= 0) {
428 dev_dbg(child, "failed to get resources\n");
429 return count ? count : -EIO;
432 resources = devm_kcalloc(hostdev, count, sizeof(*resources),
433 GFP_KERNEL);
434 if (!resources) {
435 dev_warn(hostdev, "could not allocate memory for %d resources\n",
436 count);
437 acpi_dev_free_resource_list(&resource_list);
438 return -ENOMEM;
440 count = 0;
441 list_for_each_entry(rentry, &resource_list, node) {
442 resources[count] = *rentry->res;
443 hisi_lpc_acpi_fixup_child_resource(hostdev, &resources[count]);
444 count++;
447 acpi_dev_free_resource_list(&resource_list);
449 /* translate the I/O resources */
450 for (i = 0; i < count; i++) {
451 int ret;
453 if (!(resources[i].flags & IORESOURCE_IO))
454 continue;
455 ret = hisi_lpc_acpi_xlat_io_res(adev, host, &resources[i]);
456 if (ret) {
457 dev_err(child, "translate IO range %pR failed (%d)\n",
458 &resources[i], ret);
459 return ret;
462 *res = resources;
463 *num_res = count;
465 return 0;
468 static int hisi_lpc_acpi_remove_subdev(struct device *dev, void *unused)
470 platform_device_unregister(to_platform_device(dev));
471 return 0;
474 struct hisi_lpc_acpi_cell {
475 const char *hid;
476 const char *name;
477 void *pdata;
478 size_t pdata_size;
481 static void hisi_lpc_acpi_remove(struct device *hostdev)
483 struct acpi_device *adev = ACPI_COMPANION(hostdev);
484 struct acpi_device *child;
486 device_for_each_child(hostdev, NULL, hisi_lpc_acpi_remove_subdev);
488 list_for_each_entry(child, &adev->children, node)
489 acpi_device_clear_enumerated(child);
493 * hisi_lpc_acpi_probe - probe children for ACPI FW
494 * @hostdev: LPC host device pointer
496 * Returns 0 when successful, and a negative value for failure.
498 * Create a platform device per child, fixing up the resources
499 * from bus addresses to Logical PIO addresses.
502 static int hisi_lpc_acpi_probe(struct device *hostdev)
504 struct acpi_device *adev = ACPI_COMPANION(hostdev);
505 struct acpi_device *child;
506 int ret;
508 /* Only consider the children of the host */
509 list_for_each_entry(child, &adev->children, node) {
510 const char *hid = acpi_device_hid(child);
511 const struct hisi_lpc_acpi_cell *cell;
512 struct platform_device *pdev;
513 const struct resource *res;
514 bool found = false;
515 int num_res;
517 ret = hisi_lpc_acpi_set_io_res(&child->dev, &adev->dev, &res,
518 &num_res);
519 if (ret) {
520 dev_warn(hostdev, "set resource fail (%d)\n", ret);
521 goto fail;
524 cell = (struct hisi_lpc_acpi_cell []){
525 /* ipmi */
527 .hid = "IPI0001",
528 .name = "hisi-lpc-ipmi",
530 /* 8250-compatible uart */
532 .hid = "HISI1031",
533 .name = "serial8250",
534 .pdata = (struct plat_serial8250_port []) {
536 .iobase = res->start,
537 .uartclk = 1843200,
538 .iotype = UPIO_PORT,
539 .flags = UPF_BOOT_AUTOCONF,
543 .pdata_size = 2 *
544 sizeof(struct plat_serial8250_port),
549 for (; cell && cell->name; cell++) {
550 if (!strcmp(cell->hid, hid)) {
551 found = true;
552 break;
556 if (!found) {
557 dev_warn(hostdev,
558 "could not find cell for child device (%s), discarding\n",
559 hid);
560 continue;
563 pdev = platform_device_alloc(cell->name, PLATFORM_DEVID_AUTO);
564 if (!pdev) {
565 ret = -ENOMEM;
566 goto fail;
569 pdev->dev.parent = hostdev;
570 ACPI_COMPANION_SET(&pdev->dev, child);
572 ret = platform_device_add_resources(pdev, res, num_res);
573 if (ret)
574 goto fail;
576 ret = platform_device_add_data(pdev, cell->pdata,
577 cell->pdata_size);
578 if (ret)
579 goto fail;
581 ret = platform_device_add(pdev);
582 if (ret)
583 goto fail;
585 acpi_device_set_enumerated(child);
588 return 0;
590 fail:
591 hisi_lpc_acpi_remove(hostdev);
592 return ret;
595 static const struct acpi_device_id hisi_lpc_acpi_match[] = {
596 {"HISI0191"},
599 #else
600 static int hisi_lpc_acpi_probe(struct device *dev)
602 return -ENODEV;
605 static void hisi_lpc_acpi_remove(struct device *hostdev)
608 #endif // CONFIG_ACPI
611 * hisi_lpc_probe - the probe callback function for hisi lpc host,
612 * will finish all the initialization.
613 * @pdev: the platform device corresponding to hisi lpc host
615 * Returns 0 on success, non-zero on fail.
617 static int hisi_lpc_probe(struct platform_device *pdev)
619 struct device *dev = &pdev->dev;
620 struct acpi_device *acpi_device = ACPI_COMPANION(dev);
621 struct logic_pio_hwaddr *range;
622 struct hisi_lpc_dev *lpcdev;
623 resource_size_t io_end;
624 struct resource *res;
625 int ret;
627 lpcdev = devm_kzalloc(dev, sizeof(*lpcdev), GFP_KERNEL);
628 if (!lpcdev)
629 return -ENOMEM;
631 spin_lock_init(&lpcdev->cycle_lock);
633 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
634 lpcdev->membase = devm_ioremap_resource(dev, res);
635 if (IS_ERR(lpcdev->membase))
636 return PTR_ERR(lpcdev->membase);
638 range = devm_kzalloc(dev, sizeof(*range), GFP_KERNEL);
639 if (!range)
640 return -ENOMEM;
642 range->fwnode = dev->fwnode;
643 range->flags = LOGIC_PIO_INDIRECT;
644 range->size = PIO_INDIRECT_SIZE;
645 range->hostdata = lpcdev;
646 range->ops = &hisi_lpc_ops;
647 lpcdev->io_host = range;
649 ret = logic_pio_register_range(range);
650 if (ret) {
651 dev_err(dev, "register IO range failed (%d)!\n", ret);
652 return ret;
655 /* register the LPC host PIO resources */
656 if (acpi_device)
657 ret = hisi_lpc_acpi_probe(dev);
658 else
659 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
660 if (ret) {
661 logic_pio_unregister_range(range);
662 return ret;
665 dev_set_drvdata(dev, lpcdev);
667 io_end = lpcdev->io_host->io_start + lpcdev->io_host->size;
668 dev_info(dev, "registered range [%pa - %pa]\n",
669 &lpcdev->io_host->io_start, &io_end);
671 return ret;
674 static int hisi_lpc_remove(struct platform_device *pdev)
676 struct device *dev = &pdev->dev;
677 struct acpi_device *acpi_device = ACPI_COMPANION(dev);
678 struct hisi_lpc_dev *lpcdev = dev_get_drvdata(dev);
679 struct logic_pio_hwaddr *range = lpcdev->io_host;
681 if (acpi_device)
682 hisi_lpc_acpi_remove(dev);
683 else
684 of_platform_depopulate(dev);
686 logic_pio_unregister_range(range);
688 return 0;
691 static const struct of_device_id hisi_lpc_of_match[] = {
692 { .compatible = "hisilicon,hip06-lpc", },
693 { .compatible = "hisilicon,hip07-lpc", },
697 static struct platform_driver hisi_lpc_driver = {
698 .driver = {
699 .name = DRV_NAME,
700 .of_match_table = hisi_lpc_of_match,
701 .acpi_match_table = ACPI_PTR(hisi_lpc_acpi_match),
703 .probe = hisi_lpc_probe,
704 .remove = hisi_lpc_remove,
706 builtin_platform_driver(hisi_lpc_driver);