xref: /linux/drivers/soc/mediatek/mtk-cmdq-helper.c (revision bd4af432cc71b5fbfe4833510359a6ad3ada250d)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2018 MediaTek Inc.
4 
5 #include <linux/completion.h>
6 #include <linux/errno.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/module.h>
9 #include <linux/mailbox_controller.h>
10 #include <linux/soc/mediatek/mtk-cmdq.h>
11 
12 #define CMDQ_WRITE_ENABLE_MASK	BIT(0)
13 #define CMDQ_POLL_ENABLE_MASK	BIT(0)
14 #define CMDQ_EOC_IRQ_EN		BIT(0)
15 
16 struct cmdq_instruction {
17 	union {
18 		u32 value;
19 		u32 mask;
20 	};
21 	union {
22 		u16 offset;
23 		u16 event;
24 	};
25 	u8 subsys;
26 	u8 op;
27 };
28 
29 int cmdq_dev_get_client_reg(struct device *dev,
30 			    struct cmdq_client_reg *client_reg, int idx)
31 {
32 	struct of_phandle_args spec;
33 	int err;
34 
35 	if (!client_reg)
36 		return -ENOENT;
37 
38 	err = of_parse_phandle_with_fixed_args(dev->of_node,
39 					       "mediatek,gce-client-reg",
40 					       3, idx, &spec);
41 	if (err < 0) {
42 		dev_err(dev,
43 			"error %d can't parse gce-client-reg property (%d)",
44 			err, idx);
45 
46 		return err;
47 	}
48 
49 	client_reg->subsys = (u8)spec.args[0];
50 	client_reg->offset = (u16)spec.args[1];
51 	client_reg->size = (u16)spec.args[2];
52 	of_node_put(spec.np);
53 
54 	return 0;
55 }
56 EXPORT_SYMBOL(cmdq_dev_get_client_reg);
57 
58 static void cmdq_client_timeout(struct timer_list *t)
59 {
60 	struct cmdq_client *client = from_timer(client, t, timer);
61 
62 	dev_err(client->client.dev, "cmdq timeout!\n");
63 }
64 
65 struct cmdq_client *cmdq_mbox_create(struct device *dev, int index, u32 timeout)
66 {
67 	struct cmdq_client *client;
68 
69 	client = kzalloc(sizeof(*client), GFP_KERNEL);
70 	if (!client)
71 		return (struct cmdq_client *)-ENOMEM;
72 
73 	client->timeout_ms = timeout;
74 	if (timeout != CMDQ_NO_TIMEOUT) {
75 		spin_lock_init(&client->lock);
76 		timer_setup(&client->timer, cmdq_client_timeout, 0);
77 	}
78 	client->pkt_cnt = 0;
79 	client->client.dev = dev;
80 	client->client.tx_block = false;
81 	client->client.knows_txdone = true;
82 	client->chan = mbox_request_channel(&client->client, index);
83 
84 	if (IS_ERR(client->chan)) {
85 		long err;
86 
87 		dev_err(dev, "failed to request channel\n");
88 		err = PTR_ERR(client->chan);
89 		kfree(client);
90 
91 		return ERR_PTR(err);
92 	}
93 
94 	return client;
95 }
96 EXPORT_SYMBOL(cmdq_mbox_create);
97 
98 void cmdq_mbox_destroy(struct cmdq_client *client)
99 {
100 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
101 		spin_lock(&client->lock);
102 		del_timer_sync(&client->timer);
103 		spin_unlock(&client->lock);
104 	}
105 	mbox_free_channel(client->chan);
106 	kfree(client);
107 }
108 EXPORT_SYMBOL(cmdq_mbox_destroy);
109 
110 struct cmdq_pkt *cmdq_pkt_create(struct cmdq_client *client, size_t size)
111 {
112 	struct cmdq_pkt *pkt;
113 	struct device *dev;
114 	dma_addr_t dma_addr;
115 
116 	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
117 	if (!pkt)
118 		return ERR_PTR(-ENOMEM);
119 	pkt->va_base = kzalloc(size, GFP_KERNEL);
120 	if (!pkt->va_base) {
121 		kfree(pkt);
122 		return ERR_PTR(-ENOMEM);
123 	}
124 	pkt->buf_size = size;
125 	pkt->cl = (void *)client;
126 
127 	dev = client->chan->mbox->dev;
128 	dma_addr = dma_map_single(dev, pkt->va_base, pkt->buf_size,
129 				  DMA_TO_DEVICE);
130 	if (dma_mapping_error(dev, dma_addr)) {
131 		dev_err(dev, "dma map failed, size=%u\n", (u32)(u64)size);
132 		kfree(pkt->va_base);
133 		kfree(pkt);
134 		return ERR_PTR(-ENOMEM);
135 	}
136 
137 	pkt->pa_base = dma_addr;
138 
139 	return pkt;
140 }
141 EXPORT_SYMBOL(cmdq_pkt_create);
142 
143 void cmdq_pkt_destroy(struct cmdq_pkt *pkt)
144 {
145 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
146 
147 	dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt->buf_size,
148 			 DMA_TO_DEVICE);
149 	kfree(pkt->va_base);
150 	kfree(pkt);
151 }
152 EXPORT_SYMBOL(cmdq_pkt_destroy);
153 
154 static int cmdq_pkt_append_command(struct cmdq_pkt *pkt,
155 				   struct cmdq_instruction inst)
156 {
157 	struct cmdq_instruction *cmd_ptr;
158 
159 	if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
160 		/*
161 		 * In the case of allocated buffer size (pkt->buf_size) is used
162 		 * up, the real required size (pkt->cmdq_buf_size) is still
163 		 * increased, so that the user knows how much memory should be
164 		 * ultimately allocated after appending all commands and
165 		 * flushing the command packet. Therefor, the user can call
166 		 * cmdq_pkt_create() again with the real required buffer size.
167 		 */
168 		pkt->cmd_buf_size += CMDQ_INST_SIZE;
169 		WARN_ONCE(1, "%s: buffer size %u is too small !\n",
170 			__func__, (u32)pkt->buf_size);
171 		return -ENOMEM;
172 	}
173 
174 	cmd_ptr = pkt->va_base + pkt->cmd_buf_size;
175 	*cmd_ptr = inst;
176 	pkt->cmd_buf_size += CMDQ_INST_SIZE;
177 
178 	return 0;
179 }
180 
181 int cmdq_pkt_write(struct cmdq_pkt *pkt, u8 subsys, u16 offset, u32 value)
182 {
183 	struct cmdq_instruction inst;
184 
185 	inst.op = CMDQ_CODE_WRITE;
186 	inst.value = value;
187 	inst.offset = offset;
188 	inst.subsys = subsys;
189 
190 	return cmdq_pkt_append_command(pkt, inst);
191 }
192 EXPORT_SYMBOL(cmdq_pkt_write);
193 
194 int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
195 			u16 offset, u32 value, u32 mask)
196 {
197 	struct cmdq_instruction inst = { {0} };
198 	u16 offset_mask = offset;
199 	int err;
200 
201 	if (mask != 0xffffffff) {
202 		inst.op = CMDQ_CODE_MASK;
203 		inst.mask = ~mask;
204 		err = cmdq_pkt_append_command(pkt, inst);
205 		if (err < 0)
206 			return err;
207 
208 		offset_mask |= CMDQ_WRITE_ENABLE_MASK;
209 	}
210 	err = cmdq_pkt_write(pkt, subsys, offset_mask, value);
211 
212 	return err;
213 }
214 EXPORT_SYMBOL(cmdq_pkt_write_mask);
215 
216 int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
217 {
218 	struct cmdq_instruction inst = { {0} };
219 
220 	if (event >= CMDQ_MAX_EVENT)
221 		return -EINVAL;
222 
223 	inst.op = CMDQ_CODE_WFE;
224 	inst.value = CMDQ_WFE_OPTION;
225 	inst.event = event;
226 
227 	return cmdq_pkt_append_command(pkt, inst);
228 }
229 EXPORT_SYMBOL(cmdq_pkt_wfe);
230 
231 int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
232 {
233 	struct cmdq_instruction inst = { {0} };
234 
235 	if (event >= CMDQ_MAX_EVENT)
236 		return -EINVAL;
237 
238 	inst.op = CMDQ_CODE_WFE;
239 	inst.value = CMDQ_WFE_UPDATE;
240 	inst.event = event;
241 
242 	return cmdq_pkt_append_command(pkt, inst);
243 }
244 EXPORT_SYMBOL(cmdq_pkt_clear_event);
245 
246 int cmdq_pkt_poll(struct cmdq_pkt *pkt, u8 subsys,
247 		  u16 offset, u32 value)
248 {
249 	struct cmdq_instruction inst = { {0} };
250 	int err;
251 
252 	inst.op = CMDQ_CODE_POLL;
253 	inst.value = value;
254 	inst.offset = offset;
255 	inst.subsys = subsys;
256 	err = cmdq_pkt_append_command(pkt, inst);
257 
258 	return err;
259 }
260 EXPORT_SYMBOL(cmdq_pkt_poll);
261 
262 int cmdq_pkt_poll_mask(struct cmdq_pkt *pkt, u8 subsys,
263 		       u16 offset, u32 value, u32 mask)
264 {
265 	struct cmdq_instruction inst = { {0} };
266 	int err;
267 
268 	inst.op = CMDQ_CODE_MASK;
269 	inst.mask = ~mask;
270 	err = cmdq_pkt_append_command(pkt, inst);
271 	if (err < 0)
272 		return err;
273 
274 	offset = offset | CMDQ_POLL_ENABLE_MASK;
275 	err = cmdq_pkt_poll(pkt, subsys, offset, value);
276 
277 	return err;
278 }
279 EXPORT_SYMBOL(cmdq_pkt_poll_mask);
280 
281 static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
282 {
283 	struct cmdq_instruction inst = { {0} };
284 	int err;
285 
286 	/* insert EOC and generate IRQ for each command iteration */
287 	inst.op = CMDQ_CODE_EOC;
288 	inst.value = CMDQ_EOC_IRQ_EN;
289 	err = cmdq_pkt_append_command(pkt, inst);
290 	if (err < 0)
291 		return err;
292 
293 	/* JUMP to end */
294 	inst.op = CMDQ_CODE_JUMP;
295 	inst.value = CMDQ_JUMP_PASS;
296 	err = cmdq_pkt_append_command(pkt, inst);
297 
298 	return err;
299 }
300 
301 static void cmdq_pkt_flush_async_cb(struct cmdq_cb_data data)
302 {
303 	struct cmdq_pkt *pkt = (struct cmdq_pkt *)data.data;
304 	struct cmdq_task_cb *cb = &pkt->cb;
305 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
306 
307 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
308 		unsigned long flags = 0;
309 
310 		spin_lock_irqsave(&client->lock, flags);
311 		if (--client->pkt_cnt == 0)
312 			del_timer(&client->timer);
313 		else
314 			mod_timer(&client->timer, jiffies +
315 				  msecs_to_jiffies(client->timeout_ms));
316 		spin_unlock_irqrestore(&client->lock, flags);
317 	}
318 
319 	dma_sync_single_for_cpu(client->chan->mbox->dev, pkt->pa_base,
320 				pkt->cmd_buf_size, DMA_TO_DEVICE);
321 	if (cb->cb) {
322 		data.data = cb->data;
323 		cb->cb(data);
324 	}
325 }
326 
327 int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
328 			 void *data)
329 {
330 	int err;
331 	unsigned long flags = 0;
332 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
333 
334 	err = cmdq_pkt_finalize(pkt);
335 	if (err < 0)
336 		return err;
337 
338 	pkt->cb.cb = cb;
339 	pkt->cb.data = data;
340 	pkt->async_cb.cb = cmdq_pkt_flush_async_cb;
341 	pkt->async_cb.data = pkt;
342 
343 	dma_sync_single_for_device(client->chan->mbox->dev, pkt->pa_base,
344 				   pkt->cmd_buf_size, DMA_TO_DEVICE);
345 
346 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
347 		spin_lock_irqsave(&client->lock, flags);
348 		if (client->pkt_cnt++ == 0)
349 			mod_timer(&client->timer, jiffies +
350 				  msecs_to_jiffies(client->timeout_ms));
351 		spin_unlock_irqrestore(&client->lock, flags);
352 	}
353 
354 	mbox_send_message(client->chan, pkt);
355 	/* We can send next packet immediately, so just call txdone. */
356 	mbox_client_txdone(client->chan, 0);
357 
358 	return 0;
359 }
360 EXPORT_SYMBOL(cmdq_pkt_flush_async);
361 
362 struct cmdq_flush_completion {
363 	struct completion cmplt;
364 	bool err;
365 };
366 
367 static void cmdq_pkt_flush_cb(struct cmdq_cb_data data)
368 {
369 	struct cmdq_flush_completion *cmplt;
370 
371 	cmplt = (struct cmdq_flush_completion *)data.data;
372 	if (data.sta != CMDQ_CB_NORMAL)
373 		cmplt->err = true;
374 	else
375 		cmplt->err = false;
376 	complete(&cmplt->cmplt);
377 }
378 
379 int cmdq_pkt_flush(struct cmdq_pkt *pkt)
380 {
381 	struct cmdq_flush_completion cmplt;
382 	int err;
383 
384 	init_completion(&cmplt.cmplt);
385 	err = cmdq_pkt_flush_async(pkt, cmdq_pkt_flush_cb, &cmplt);
386 	if (err < 0)
387 		return err;
388 	wait_for_completion(&cmplt.cmplt);
389 
390 	return cmplt.err ? -EFAULT : 0;
391 }
392 EXPORT_SYMBOL(cmdq_pkt_flush);
393 
394 MODULE_LICENSE("GPL v2");
395