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 #define CMDQ_EOC_CMD		((u64)((CMDQ_CODE_EOC << CMDQ_OP_CODE_SHIFT)) \
16 				<< 32 | CMDQ_EOC_IRQ_EN)
17 
18 struct cmdq_instruction {
19 	union {
20 		u32 value;
21 		u32 mask;
22 	};
23 	union {
24 		u16 offset;
25 		u16 event;
26 	};
27 	u8 subsys;
28 	u8 op;
29 };
30 
31 int cmdq_dev_get_client_reg(struct device *dev,
32 			    struct cmdq_client_reg *client_reg, int idx)
33 {
34 	struct of_phandle_args spec;
35 	int err;
36 
37 	if (!client_reg)
38 		return -ENOENT;
39 
40 	err = of_parse_phandle_with_fixed_args(dev->of_node,
41 					       "mediatek,gce-client-reg",
42 					       3, idx, &spec);
43 	if (err < 0) {
44 		dev_err(dev,
45 			"error %d can't parse gce-client-reg property (%d)",
46 			err, idx);
47 
48 		return err;
49 	}
50 
51 	client_reg->subsys = (u8)spec.args[0];
52 	client_reg->offset = (u16)spec.args[1];
53 	client_reg->size = (u16)spec.args[2];
54 	of_node_put(spec.np);
55 
56 	return 0;
57 }
58 EXPORT_SYMBOL(cmdq_dev_get_client_reg);
59 
60 static void cmdq_client_timeout(struct timer_list *t)
61 {
62 	struct cmdq_client *client = from_timer(client, t, timer);
63 
64 	dev_err(client->client.dev, "cmdq timeout!\n");
65 }
66 
67 struct cmdq_client *cmdq_mbox_create(struct device *dev, int index, u32 timeout)
68 {
69 	struct cmdq_client *client;
70 
71 	client = kzalloc(sizeof(*client), GFP_KERNEL);
72 	if (!client)
73 		return (struct cmdq_client *)-ENOMEM;
74 
75 	client->timeout_ms = timeout;
76 	if (timeout != CMDQ_NO_TIMEOUT) {
77 		spin_lock_init(&client->lock);
78 		timer_setup(&client->timer, cmdq_client_timeout, 0);
79 	}
80 	client->pkt_cnt = 0;
81 	client->client.dev = dev;
82 	client->client.tx_block = false;
83 	client->chan = mbox_request_channel(&client->client, index);
84 
85 	if (IS_ERR(client->chan)) {
86 		long err;
87 
88 		dev_err(dev, "failed to request channel\n");
89 		err = PTR_ERR(client->chan);
90 		kfree(client);
91 
92 		return ERR_PTR(err);
93 	}
94 
95 	return client;
96 }
97 EXPORT_SYMBOL(cmdq_mbox_create);
98 
99 void cmdq_mbox_destroy(struct cmdq_client *client)
100 {
101 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
102 		spin_lock(&client->lock);
103 		del_timer_sync(&client->timer);
104 		spin_unlock(&client->lock);
105 	}
106 	mbox_free_channel(client->chan);
107 	kfree(client);
108 }
109 EXPORT_SYMBOL(cmdq_mbox_destroy);
110 
111 struct cmdq_pkt *cmdq_pkt_create(struct cmdq_client *client, size_t size)
112 {
113 	struct cmdq_pkt *pkt;
114 	struct device *dev;
115 	dma_addr_t dma_addr;
116 
117 	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
118 	if (!pkt)
119 		return ERR_PTR(-ENOMEM);
120 	pkt->va_base = kzalloc(size, GFP_KERNEL);
121 	if (!pkt->va_base) {
122 		kfree(pkt);
123 		return ERR_PTR(-ENOMEM);
124 	}
125 	pkt->buf_size = size;
126 	pkt->cl = (void *)client;
127 
128 	dev = client->chan->mbox->dev;
129 	dma_addr = dma_map_single(dev, pkt->va_base, pkt->buf_size,
130 				  DMA_TO_DEVICE);
131 	if (dma_mapping_error(dev, dma_addr)) {
132 		dev_err(dev, "dma map failed, size=%u\n", (u32)(u64)size);
133 		kfree(pkt->va_base);
134 		kfree(pkt);
135 		return ERR_PTR(-ENOMEM);
136 	}
137 
138 	pkt->pa_base = dma_addr;
139 
140 	return pkt;
141 }
142 EXPORT_SYMBOL(cmdq_pkt_create);
143 
144 void cmdq_pkt_destroy(struct cmdq_pkt *pkt)
145 {
146 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
147 
148 	dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt->buf_size,
149 			 DMA_TO_DEVICE);
150 	kfree(pkt->va_base);
151 	kfree(pkt);
152 }
153 EXPORT_SYMBOL(cmdq_pkt_destroy);
154 
155 static int cmdq_pkt_append_command(struct cmdq_pkt *pkt,
156 				   struct cmdq_instruction inst)
157 {
158 	struct cmdq_instruction *cmd_ptr;
159 
160 	if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
161 		/*
162 		 * In the case of allocated buffer size (pkt->buf_size) is used
163 		 * up, the real required size (pkt->cmdq_buf_size) is still
164 		 * increased, so that the user knows how much memory should be
165 		 * ultimately allocated after appending all commands and
166 		 * flushing the command packet. Therefor, the user can call
167 		 * cmdq_pkt_create() again with the real required buffer size.
168 		 */
169 		pkt->cmd_buf_size += CMDQ_INST_SIZE;
170 		WARN_ONCE(1, "%s: buffer size %u is too small !\n",
171 			__func__, (u32)pkt->buf_size);
172 		return -ENOMEM;
173 	}
174 
175 	cmd_ptr = pkt->va_base + pkt->cmd_buf_size;
176 	*cmd_ptr = inst;
177 	pkt->cmd_buf_size += CMDQ_INST_SIZE;
178 
179 	return 0;
180 }
181 
182 int cmdq_pkt_write(struct cmdq_pkt *pkt, u8 subsys, u16 offset, u32 value)
183 {
184 	struct cmdq_instruction inst;
185 
186 	inst.op = CMDQ_CODE_WRITE;
187 	inst.value = value;
188 	inst.offset = offset;
189 	inst.subsys = subsys;
190 
191 	return cmdq_pkt_append_command(pkt, inst);
192 }
193 EXPORT_SYMBOL(cmdq_pkt_write);
194 
195 int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
196 			u16 offset, u32 value, u32 mask)
197 {
198 	struct cmdq_instruction inst = { {0} };
199 	u16 offset_mask = offset;
200 	int err;
201 
202 	if (mask != 0xffffffff) {
203 		inst.op = CMDQ_CODE_MASK;
204 		inst.mask = ~mask;
205 		err = cmdq_pkt_append_command(pkt, inst);
206 		if (err < 0)
207 			return err;
208 
209 		offset_mask |= CMDQ_WRITE_ENABLE_MASK;
210 	}
211 	err = cmdq_pkt_write(pkt, subsys, offset_mask, value);
212 
213 	return err;
214 }
215 EXPORT_SYMBOL(cmdq_pkt_write_mask);
216 
217 int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
218 {
219 	struct cmdq_instruction inst = { {0} };
220 
221 	if (event >= CMDQ_MAX_EVENT)
222 		return -EINVAL;
223 
224 	inst.op = CMDQ_CODE_WFE;
225 	inst.value = CMDQ_WFE_OPTION;
226 	inst.event = event;
227 
228 	return cmdq_pkt_append_command(pkt, inst);
229 }
230 EXPORT_SYMBOL(cmdq_pkt_wfe);
231 
232 int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
233 {
234 	struct cmdq_instruction inst = { {0} };
235 
236 	if (event >= CMDQ_MAX_EVENT)
237 		return -EINVAL;
238 
239 	inst.op = CMDQ_CODE_WFE;
240 	inst.value = CMDQ_WFE_UPDATE;
241 	inst.event = event;
242 
243 	return cmdq_pkt_append_command(pkt, inst);
244 }
245 EXPORT_SYMBOL(cmdq_pkt_clear_event);
246 
247 int cmdq_pkt_poll(struct cmdq_pkt *pkt, u8 subsys,
248 		  u16 offset, u32 value)
249 {
250 	struct cmdq_instruction inst = { {0} };
251 	int err;
252 
253 	inst.op = CMDQ_CODE_POLL;
254 	inst.value = value;
255 	inst.offset = offset;
256 	inst.subsys = subsys;
257 	err = cmdq_pkt_append_command(pkt, inst);
258 
259 	return err;
260 }
261 EXPORT_SYMBOL(cmdq_pkt_poll);
262 
263 int cmdq_pkt_poll_mask(struct cmdq_pkt *pkt, u8 subsys,
264 		       u16 offset, u32 value, u32 mask)
265 {
266 	struct cmdq_instruction inst = { {0} };
267 	int err;
268 
269 	inst.op = CMDQ_CODE_MASK;
270 	inst.mask = ~mask;
271 	err = cmdq_pkt_append_command(pkt, inst);
272 	if (err < 0)
273 		return err;
274 
275 	offset = offset | CMDQ_POLL_ENABLE_MASK;
276 	err = cmdq_pkt_poll(pkt, subsys, offset, value);
277 
278 	return err;
279 }
280 EXPORT_SYMBOL(cmdq_pkt_poll_mask);
281 
282 static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
283 {
284 	struct cmdq_instruction inst = { {0} };
285 	int err;
286 
287 	/* insert EOC and generate IRQ for each command iteration */
288 	inst.op = CMDQ_CODE_EOC;
289 	inst.value = CMDQ_EOC_IRQ_EN;
290 	err = cmdq_pkt_append_command(pkt, inst);
291 	if (err < 0)
292 		return err;
293 
294 	/* JUMP to end */
295 	inst.op = CMDQ_CODE_JUMP;
296 	inst.value = CMDQ_JUMP_PASS;
297 	err = cmdq_pkt_append_command(pkt, inst);
298 
299 	return err;
300 }
301 
302 static void cmdq_pkt_flush_async_cb(struct cmdq_cb_data data)
303 {
304 	struct cmdq_pkt *pkt = (struct cmdq_pkt *)data.data;
305 	struct cmdq_task_cb *cb = &pkt->cb;
306 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
307 
308 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
309 		unsigned long flags = 0;
310 
311 		spin_lock_irqsave(&client->lock, flags);
312 		if (--client->pkt_cnt == 0)
313 			del_timer(&client->timer);
314 		else
315 			mod_timer(&client->timer, jiffies +
316 				  msecs_to_jiffies(client->timeout_ms));
317 		spin_unlock_irqrestore(&client->lock, flags);
318 	}
319 
320 	dma_sync_single_for_cpu(client->chan->mbox->dev, pkt->pa_base,
321 				pkt->cmd_buf_size, DMA_TO_DEVICE);
322 	if (cb->cb) {
323 		data.data = cb->data;
324 		cb->cb(data);
325 	}
326 }
327 
328 int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
329 			 void *data)
330 {
331 	int err;
332 	unsigned long flags = 0;
333 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
334 
335 	err = cmdq_pkt_finalize(pkt);
336 	if (err < 0)
337 		return err;
338 
339 	pkt->cb.cb = cb;
340 	pkt->cb.data = data;
341 	pkt->async_cb.cb = cmdq_pkt_flush_async_cb;
342 	pkt->async_cb.data = pkt;
343 
344 	dma_sync_single_for_device(client->chan->mbox->dev, pkt->pa_base,
345 				   pkt->cmd_buf_size, DMA_TO_DEVICE);
346 
347 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
348 		spin_lock_irqsave(&client->lock, flags);
349 		if (client->pkt_cnt++ == 0)
350 			mod_timer(&client->timer, jiffies +
351 				  msecs_to_jiffies(client->timeout_ms));
352 		spin_unlock_irqrestore(&client->lock, flags);
353 	}
354 
355 	mbox_send_message(client->chan, pkt);
356 	/* We can send next packet immediately, so just call txdone. */
357 	mbox_client_txdone(client->chan, 0);
358 
359 	return 0;
360 }
361 EXPORT_SYMBOL(cmdq_pkt_flush_async);
362 
363 struct cmdq_flush_completion {
364 	struct completion cmplt;
365 	bool err;
366 };
367 
368 static void cmdq_pkt_flush_cb(struct cmdq_cb_data data)
369 {
370 	struct cmdq_flush_completion *cmplt;
371 
372 	cmplt = (struct cmdq_flush_completion *)data.data;
373 	if (data.sta != CMDQ_CB_NORMAL)
374 		cmplt->err = true;
375 	else
376 		cmplt->err = false;
377 	complete(&cmplt->cmplt);
378 }
379 
380 int cmdq_pkt_flush(struct cmdq_pkt *pkt)
381 {
382 	struct cmdq_flush_completion cmplt;
383 	int err;
384 
385 	init_completion(&cmplt.cmplt);
386 	err = cmdq_pkt_flush_async(pkt, cmdq_pkt_flush_cb, &cmplt);
387 	if (err < 0)
388 		return err;
389 	wait_for_completion(&cmplt.cmplt);
390 
391 	return cmplt.err ? -EFAULT : 0;
392 }
393 EXPORT_SYMBOL(cmdq_pkt_flush);
394 
395 MODULE_LICENSE("GPL v2");
396