Merge tag 'uml-for-linus-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-block.git] / drivers / rpmsg / qcom_glink_rpm.c
CommitLineData
84369fbe 1// SPDX-License-Identifier: GPL-2.0
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2/*
3 * Copyright (c) 2016-2017, Linaro Ltd
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4 */
5
6#include <linux/idr.h>
7#include <linux/interrupt.h>
8#include <linux/io.h>
9#include <linux/list.h>
10#include <linux/mfd/syscon.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/of_address.h>
f424d1cb 14#include <linux/of_irq.h>
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15#include <linux/platform_device.h>
16#include <linux/regmap.h>
17#include <linux/rpmsg.h>
18#include <linux/slab.h>
19#include <linux/workqueue.h>
20#include <linux/mailbox_client.h>
21
22#include "rpmsg_internal.h"
835764dd 23#include "qcom_glink_native.h"
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24
25#define RPM_TOC_SIZE 256
26#define RPM_TOC_MAGIC 0x67727430 /* grt0 */
27#define RPM_TOC_MAX_ENTRIES ((RPM_TOC_SIZE - sizeof(struct rpm_toc)) / \
28 sizeof(struct rpm_toc_entry))
29
30#define RPM_TX_FIFO_ID 0x61703272 /* ap2r */
31#define RPM_RX_FIFO_ID 0x72326170 /* r2ap */
32
835764dd 33#define to_rpm_pipe(p) container_of(p, struct glink_rpm_pipe, native)
e45c5dc2 34
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35struct rpm_toc_entry {
36 __le32 id;
37 __le32 offset;
38 __le32 size;
39} __packed;
40
41struct rpm_toc {
42 __le32 magic;
43 __le32 count;
44
45 struct rpm_toc_entry entries[];
46} __packed;
47
b4f8e52b 48struct glink_rpm_pipe {
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49 struct qcom_glink_pipe native;
50
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51 void __iomem *tail;
52 void __iomem *head;
53
54 void __iomem *fifo;
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55};
56
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57struct glink_rpm {
58 struct qcom_glink *glink;
59
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60 int irq;
61
62 struct mbox_client mbox_client;
63 struct mbox_chan *mbox_chan;
64
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65 struct glink_rpm_pipe rx_pipe;
66 struct glink_rpm_pipe tx_pipe;
67};
68
e45c5dc2 69static size_t glink_rpm_rx_avail(struct qcom_glink_pipe *glink_pipe)
b4f8e52b 70{
e45c5dc2 71 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
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72 unsigned int head;
73 unsigned int tail;
74
75 head = readl(pipe->head);
76 tail = readl(pipe->tail);
77
78 if (head < tail)
e45c5dc2 79 return pipe->native.length - tail + head;
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80 else
81 return head - tail;
82}
83
a8f500c6 84static void glink_rpm_rx_peek(struct qcom_glink_pipe *glink_pipe,
b88eee97 85 void *data, unsigned int offset, size_t count)
b4f8e52b 86{
e45c5dc2 87 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
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88 unsigned int tail;
89 size_t len;
90
91 tail = readl(pipe->tail);
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92 tail += offset;
93 if (tail >= pipe->native.length)
94 tail -= pipe->native.length;
b4f8e52b 95
e45c5dc2 96 len = min_t(size_t, count, pipe->native.length - tail);
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97 if (len) {
98 __ioread32_copy(data, pipe->fifo + tail,
99 len / sizeof(u32));
100 }
101
102 if (len != count) {
103 __ioread32_copy(data + len, pipe->fifo,
104 (count - len) / sizeof(u32));
105 }
106}
107
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108static void glink_rpm_rx_advance(struct qcom_glink_pipe *glink_pipe,
109 size_t count)
110{
111 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
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112 unsigned int tail;
113
114 tail = readl(pipe->tail);
115
116 tail += count;
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117 if (tail >= pipe->native.length)
118 tail -= pipe->native.length;
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119
120 writel(tail, pipe->tail);
121}
122
e45c5dc2 123static size_t glink_rpm_tx_avail(struct qcom_glink_pipe *glink_pipe)
b4f8e52b 124{
e45c5dc2 125 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
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126 unsigned int head;
127 unsigned int tail;
128
129 head = readl(pipe->head);
130 tail = readl(pipe->tail);
131
132 if (tail <= head)
e45c5dc2 133 return pipe->native.length - head + tail;
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134 else
135 return tail - head;
136}
137
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138static unsigned int glink_rpm_tx_write_one(struct glink_rpm_pipe *pipe,
139 unsigned int head,
140 const void *data, size_t count)
b4f8e52b 141{
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142 size_t len;
143
e45c5dc2 144 len = min_t(size_t, count, pipe->native.length - head);
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145 if (len) {
146 __iowrite32_copy(pipe->fifo + head, data,
147 len / sizeof(u32));
148 }
149
150 if (len != count) {
151 __iowrite32_copy(pipe->fifo, data + len,
152 (count - len) / sizeof(u32));
153 }
154
155 head += count;
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156 if (head >= pipe->native.length)
157 head -= pipe->native.length;
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158
159 return head;
160}
161
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162static void glink_rpm_tx_write(struct qcom_glink_pipe *glink_pipe,
163 const void *hdr, size_t hlen,
164 const void *data, size_t dlen)
165{
166 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
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167 size_t tlen = hlen + dlen;
168 size_t aligned_dlen;
e45c5dc2 169 unsigned int head;
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170 char padding[8] = {0};
171 size_t pad;
172
173 /* Header length comes from glink native and is always 4 byte aligned */
174 if (WARN(hlen % 4, "Glink Header length must be 4 bytes aligned\n"))
175 return;
176
177 /*
178 * Move the unaligned tail of the message to the padding chunk, to
179 * ensure word aligned accesses
180 */
181 aligned_dlen = ALIGN_DOWN(dlen, 4);
182 if (aligned_dlen != dlen)
183 memcpy(padding, data + aligned_dlen, dlen - aligned_dlen);
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184
185 head = readl(pipe->head);
186 head = glink_rpm_tx_write_one(pipe, head, hdr, hlen);
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187 head = glink_rpm_tx_write_one(pipe, head, data, aligned_dlen);
188
189 pad = ALIGN(tlen, 8) - ALIGN_DOWN(tlen, 4);
190 if (pad)
191 head = glink_rpm_tx_write_one(pipe, head, padding, pad);
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192 writel(head, pipe->head);
193}
194
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195static void glink_rpm_tx_kick(struct qcom_glink_pipe *glink_pipe)
196{
197 struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
198 struct glink_rpm *rpm = container_of(pipe, struct glink_rpm, tx_pipe);
199
200 mbox_send_message(rpm->mbox_chan, NULL);
201 mbox_client_txdone(rpm->mbox_chan, 0);
202}
203
204static irqreturn_t qcom_glink_rpm_intr(int irq, void *data)
205{
206 struct glink_rpm *rpm = data;
207
208 qcom_glink_native_rx(rpm->glink);
209
210 return IRQ_HANDLED;
211}
212
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213static int glink_rpm_parse_toc(struct device *dev,
214 void __iomem *msg_ram,
215 size_t msg_ram_size,
216 struct glink_rpm_pipe *rx,
217 struct glink_rpm_pipe *tx)
218{
219 struct rpm_toc *toc;
220 int num_entries;
221 unsigned int id;
222 size_t offset;
223 size_t size;
224 void *buf;
225 int i;
226
227 buf = kzalloc(RPM_TOC_SIZE, GFP_KERNEL);
228 if (!buf)
229 return -ENOMEM;
230
231 __ioread32_copy(buf, msg_ram + msg_ram_size - RPM_TOC_SIZE,
232 RPM_TOC_SIZE / sizeof(u32));
233
234 toc = buf;
235
236 if (le32_to_cpu(toc->magic) != RPM_TOC_MAGIC) {
237 dev_err(dev, "RPM TOC has invalid magic\n");
238 goto err_inval;
239 }
240
241 num_entries = le32_to_cpu(toc->count);
242 if (num_entries > RPM_TOC_MAX_ENTRIES) {
243 dev_err(dev, "Invalid number of toc entries\n");
244 goto err_inval;
245 }
246
247 for (i = 0; i < num_entries; i++) {
248 id = le32_to_cpu(toc->entries[i].id);
249 offset = le32_to_cpu(toc->entries[i].offset);
250 size = le32_to_cpu(toc->entries[i].size);
251
252 if (offset > msg_ram_size || offset + size > msg_ram_size) {
253 dev_err(dev, "TOC entry with invalid size\n");
254 continue;
255 }
256
257 switch (id) {
258 case RPM_RX_FIFO_ID:
e45c5dc2 259 rx->native.length = size;
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260
261 rx->tail = msg_ram + offset;
262 rx->head = msg_ram + offset + sizeof(u32);
263 rx->fifo = msg_ram + offset + 2 * sizeof(u32);
264 break;
265 case RPM_TX_FIFO_ID:
e45c5dc2 266 tx->native.length = size;
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267
268 tx->tail = msg_ram + offset;
269 tx->head = msg_ram + offset + sizeof(u32);
270 tx->fifo = msg_ram + offset + 2 * sizeof(u32);
271 break;
272 }
273 }
274
275 if (!rx->fifo || !tx->fifo) {
276 dev_err(dev, "Unable to find rx and tx descriptors\n");
277 goto err_inval;
278 }
279
280 kfree(buf);
281 return 0;
282
283err_inval:
284 kfree(buf);
285 return -EINVAL;
286}
287
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288static int glink_rpm_probe(struct platform_device *pdev)
289{
290 struct qcom_glink *glink;
178c3af4 291 struct glink_rpm *rpm;
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292 struct device_node *np;
293 void __iomem *msg_ram;
294 size_t msg_ram_size;
295 struct device *dev = &pdev->dev;
296 struct resource r;
297 int ret;
298
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299 rpm = devm_kzalloc(&pdev->dev, sizeof(*rpm), GFP_KERNEL);
300 if (!rpm)
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301 return -ENOMEM;
302
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303 np = of_parse_phandle(dev->of_node, "qcom,rpm-msg-ram", 0);
304 ret = of_address_to_resource(np, 0, &r);
305 of_node_put(np);
306 if (ret)
307 return ret;
308
309 msg_ram = devm_ioremap(dev, r.start, resource_size(&r));
310 msg_ram_size = resource_size(&r);
311 if (!msg_ram)
312 return -ENOMEM;
313
314 ret = glink_rpm_parse_toc(dev, msg_ram, msg_ram_size,
178c3af4 315 &rpm->rx_pipe, &rpm->tx_pipe);
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316 if (ret)
317 return ret;
318
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319 rpm->irq = of_irq_get(dev->of_node, 0);
320 ret = devm_request_irq(dev, rpm->irq, qcom_glink_rpm_intr,
321 IRQF_NO_SUSPEND | IRQF_NO_AUTOEN,
322 "glink-rpm", rpm);
323 if (ret) {
324 dev_err(dev, "failed to request IRQ\n");
325 return ret;
326 }
327
328 rpm->mbox_client.dev = dev;
329 rpm->mbox_client.knows_txdone = true;
330 rpm->mbox_chan = mbox_request_channel(&rpm->mbox_client, 0);
331 if (IS_ERR(rpm->mbox_chan))
332 return dev_err_probe(dev, PTR_ERR(rpm->mbox_chan), "failed to acquire IPC channel\n");
333
e45c5dc2 334 /* Pipe specific accessors */
178c3af4 335 rpm->rx_pipe.native.avail = glink_rpm_rx_avail;
a8f500c6 336 rpm->rx_pipe.native.peek = glink_rpm_rx_peek;
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337 rpm->rx_pipe.native.advance = glink_rpm_rx_advance;
338 rpm->tx_pipe.native.avail = glink_rpm_tx_avail;
339 rpm->tx_pipe.native.write = glink_rpm_tx_write;
f424d1cb 340 rpm->tx_pipe.native.kick = glink_rpm_tx_kick;
e45c5dc2 341
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342 writel(0, rpm->tx_pipe.head);
343 writel(0, rpm->rx_pipe.tail);
b4f8e52b 344
178c3af4 345 glink = qcom_glink_native_probe(dev,
d31ad615 346 0,
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347 &rpm->rx_pipe.native,
348 &rpm->tx_pipe.native,
933b45da 349 true);
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350 if (IS_ERR(glink)) {
351 mbox_free_channel(rpm->mbox_chan);
6799c434 352 return PTR_ERR(glink);
f424d1cb 353 }
b4f8e52b 354
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355 rpm->glink = glink;
356
357 platform_set_drvdata(pdev, rpm);
b4f8e52b 358
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359 enable_irq(rpm->irq);
360
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361 return 0;
362}
363
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364static int glink_rpm_remove(struct platform_device *pdev)
365{
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366 struct glink_rpm *rpm = platform_get_drvdata(pdev);
367 struct qcom_glink *glink = rpm->glink;
b4f8e52b 368
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369 disable_irq(rpm->irq);
370
835764dd 371 qcom_glink_native_remove(glink);
b4f8e52b 372
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373 mbox_free_channel(rpm->mbox_chan);
374
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375 return 0;
376}
377
378static const struct of_device_id glink_rpm_of_match[] = {
379 { .compatible = "qcom,glink-rpm" },
380 {}
381};
382MODULE_DEVICE_TABLE(of, glink_rpm_of_match);
383
384static struct platform_driver glink_rpm_driver = {
385 .probe = glink_rpm_probe,
386 .remove = glink_rpm_remove,
387 .driver = {
388 .name = "qcom_glink_rpm",
389 .of_match_table = glink_rpm_of_match,
390 },
391};
392
393static int __init glink_rpm_init(void)
394{
395 return platform_driver_register(&glink_rpm_driver);
396}
397subsys_initcall(glink_rpm_init);
398
399static void __exit glink_rpm_exit(void)
400{
401 platform_driver_unregister(&glink_rpm_driver);
402}
403module_exit(glink_rpm_exit);
404
405MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>");
406MODULE_DESCRIPTION("Qualcomm GLINK RPM driver");
407MODULE_LICENSE("GPL v2");