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->chan = mbox_request_channel(&client->client, index);
82 
83 	if (IS_ERR(client->chan)) {
84 		long err;
85 
86 		dev_err(dev, "failed to request channel\n");
87 		err = PTR_ERR(client->chan);
88 		kfree(client);
89 
90 		return ERR_PTR(err);
91 	}
92 
93 	return client;
94 }
95 EXPORT_SYMBOL(cmdq_mbox_create);
96 
97 void cmdq_mbox_destroy(struct cmdq_client *client)
98 {
99 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
100 		spin_lock(&client->lock);
101 		del_timer_sync(&client->timer);
102 		spin_unlock(&client->lock);
103 	}
104 	mbox_free_channel(client->chan);
105 	kfree(client);
106 }
107 EXPORT_SYMBOL(cmdq_mbox_destroy);
108 
109 struct cmdq_pkt *cmdq_pkt_create(struct cmdq_client *client, size_t size)
110 {
111 	struct cmdq_pkt *pkt;
112 	struct device *dev;
113 	dma_addr_t dma_addr;
114 
115 	pkt = kzalloc(sizeof(*pkt), GFP_KERNEL);
116 	if (!pkt)
117 		return ERR_PTR(-ENOMEM);
118 	pkt->va_base = kzalloc(size, GFP_KERNEL);
119 	if (!pkt->va_base) {
120 		kfree(pkt);
121 		return ERR_PTR(-ENOMEM);
122 	}
123 	pkt->buf_size = size;
124 	pkt->cl = (void *)client;
125 
126 	dev = client->chan->mbox->dev;
127 	dma_addr = dma_map_single(dev, pkt->va_base, pkt->buf_size,
128 				  DMA_TO_DEVICE);
129 	if (dma_mapping_error(dev, dma_addr)) {
130 		dev_err(dev, "dma map failed, size=%u\n", (u32)(u64)size);
131 		kfree(pkt->va_base);
132 		kfree(pkt);
133 		return ERR_PTR(-ENOMEM);
134 	}
135 
136 	pkt->pa_base = dma_addr;
137 
138 	return pkt;
139 }
140 EXPORT_SYMBOL(cmdq_pkt_create);
141 
142 void cmdq_pkt_destroy(struct cmdq_pkt *pkt)
143 {
144 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
145 
146 	dma_unmap_single(client->chan->mbox->dev, pkt->pa_base, pkt->buf_size,
147 			 DMA_TO_DEVICE);
148 	kfree(pkt->va_base);
149 	kfree(pkt);
150 }
151 EXPORT_SYMBOL(cmdq_pkt_destroy);
152 
153 static int cmdq_pkt_append_command(struct cmdq_pkt *pkt,
154 				   struct cmdq_instruction inst)
155 {
156 	struct cmdq_instruction *cmd_ptr;
157 
158 	if (unlikely(pkt->cmd_buf_size + CMDQ_INST_SIZE > pkt->buf_size)) {
159 		/*
160 		 * In the case of allocated buffer size (pkt->buf_size) is used
161 		 * up, the real required size (pkt->cmdq_buf_size) is still
162 		 * increased, so that the user knows how much memory should be
163 		 * ultimately allocated after appending all commands and
164 		 * flushing the command packet. Therefor, the user can call
165 		 * cmdq_pkt_create() again with the real required buffer size.
166 		 */
167 		pkt->cmd_buf_size += CMDQ_INST_SIZE;
168 		WARN_ONCE(1, "%s: buffer size %u is too small !\n",
169 			__func__, (u32)pkt->buf_size);
170 		return -ENOMEM;
171 	}
172 
173 	cmd_ptr = pkt->va_base + pkt->cmd_buf_size;
174 	*cmd_ptr = inst;
175 	pkt->cmd_buf_size += CMDQ_INST_SIZE;
176 
177 	return 0;
178 }
179 
180 int cmdq_pkt_write(struct cmdq_pkt *pkt, u8 subsys, u16 offset, u32 value)
181 {
182 	struct cmdq_instruction inst;
183 
184 	inst.op = CMDQ_CODE_WRITE;
185 	inst.value = value;
186 	inst.offset = offset;
187 	inst.subsys = subsys;
188 
189 	return cmdq_pkt_append_command(pkt, inst);
190 }
191 EXPORT_SYMBOL(cmdq_pkt_write);
192 
193 int cmdq_pkt_write_mask(struct cmdq_pkt *pkt, u8 subsys,
194 			u16 offset, u32 value, u32 mask)
195 {
196 	struct cmdq_instruction inst = { {0} };
197 	u16 offset_mask = offset;
198 	int err;
199 
200 	if (mask != 0xffffffff) {
201 		inst.op = CMDQ_CODE_MASK;
202 		inst.mask = ~mask;
203 		err = cmdq_pkt_append_command(pkt, inst);
204 		if (err < 0)
205 			return err;
206 
207 		offset_mask |= CMDQ_WRITE_ENABLE_MASK;
208 	}
209 	err = cmdq_pkt_write(pkt, subsys, offset_mask, value);
210 
211 	return err;
212 }
213 EXPORT_SYMBOL(cmdq_pkt_write_mask);
214 
215 int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event)
216 {
217 	struct cmdq_instruction inst = { {0} };
218 
219 	if (event >= CMDQ_MAX_EVENT)
220 		return -EINVAL;
221 
222 	inst.op = CMDQ_CODE_WFE;
223 	inst.value = CMDQ_WFE_OPTION;
224 	inst.event = event;
225 
226 	return cmdq_pkt_append_command(pkt, inst);
227 }
228 EXPORT_SYMBOL(cmdq_pkt_wfe);
229 
230 int cmdq_pkt_clear_event(struct cmdq_pkt *pkt, u16 event)
231 {
232 	struct cmdq_instruction inst = { {0} };
233 
234 	if (event >= CMDQ_MAX_EVENT)
235 		return -EINVAL;
236 
237 	inst.op = CMDQ_CODE_WFE;
238 	inst.value = CMDQ_WFE_UPDATE;
239 	inst.event = event;
240 
241 	return cmdq_pkt_append_command(pkt, inst);
242 }
243 EXPORT_SYMBOL(cmdq_pkt_clear_event);
244 
245 int cmdq_pkt_poll(struct cmdq_pkt *pkt, u8 subsys,
246 		  u16 offset, u32 value)
247 {
248 	struct cmdq_instruction inst = { {0} };
249 	int err;
250 
251 	inst.op = CMDQ_CODE_POLL;
252 	inst.value = value;
253 	inst.offset = offset;
254 	inst.subsys = subsys;
255 	err = cmdq_pkt_append_command(pkt, inst);
256 
257 	return err;
258 }
259 EXPORT_SYMBOL(cmdq_pkt_poll);
260 
261 int cmdq_pkt_poll_mask(struct cmdq_pkt *pkt, u8 subsys,
262 		       u16 offset, u32 value, u32 mask)
263 {
264 	struct cmdq_instruction inst = { {0} };
265 	int err;
266 
267 	inst.op = CMDQ_CODE_MASK;
268 	inst.mask = ~mask;
269 	err = cmdq_pkt_append_command(pkt, inst);
270 	if (err < 0)
271 		return err;
272 
273 	offset = offset | CMDQ_POLL_ENABLE_MASK;
274 	err = cmdq_pkt_poll(pkt, subsys, offset, value);
275 
276 	return err;
277 }
278 EXPORT_SYMBOL(cmdq_pkt_poll_mask);
279 
280 static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
281 {
282 	struct cmdq_instruction inst = { {0} };
283 	int err;
284 
285 	/* insert EOC and generate IRQ for each command iteration */
286 	inst.op = CMDQ_CODE_EOC;
287 	inst.value = CMDQ_EOC_IRQ_EN;
288 	err = cmdq_pkt_append_command(pkt, inst);
289 	if (err < 0)
290 		return err;
291 
292 	/* JUMP to end */
293 	inst.op = CMDQ_CODE_JUMP;
294 	inst.value = CMDQ_JUMP_PASS;
295 	err = cmdq_pkt_append_command(pkt, inst);
296 
297 	return err;
298 }
299 
300 static void cmdq_pkt_flush_async_cb(struct cmdq_cb_data data)
301 {
302 	struct cmdq_pkt *pkt = (struct cmdq_pkt *)data.data;
303 	struct cmdq_task_cb *cb = &pkt->cb;
304 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
305 
306 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
307 		unsigned long flags = 0;
308 
309 		spin_lock_irqsave(&client->lock, flags);
310 		if (--client->pkt_cnt == 0)
311 			del_timer(&client->timer);
312 		else
313 			mod_timer(&client->timer, jiffies +
314 				  msecs_to_jiffies(client->timeout_ms));
315 		spin_unlock_irqrestore(&client->lock, flags);
316 	}
317 
318 	dma_sync_single_for_cpu(client->chan->mbox->dev, pkt->pa_base,
319 				pkt->cmd_buf_size, DMA_TO_DEVICE);
320 	if (cb->cb) {
321 		data.data = cb->data;
322 		cb->cb(data);
323 	}
324 }
325 
326 int cmdq_pkt_flush_async(struct cmdq_pkt *pkt, cmdq_async_flush_cb cb,
327 			 void *data)
328 {
329 	int err;
330 	unsigned long flags = 0;
331 	struct cmdq_client *client = (struct cmdq_client *)pkt->cl;
332 
333 	err = cmdq_pkt_finalize(pkt);
334 	if (err < 0)
335 		return err;
336 
337 	pkt->cb.cb = cb;
338 	pkt->cb.data = data;
339 	pkt->async_cb.cb = cmdq_pkt_flush_async_cb;
340 	pkt->async_cb.data = pkt;
341 
342 	dma_sync_single_for_device(client->chan->mbox->dev, pkt->pa_base,
343 				   pkt->cmd_buf_size, DMA_TO_DEVICE);
344 
345 	if (client->timeout_ms != CMDQ_NO_TIMEOUT) {
346 		spin_lock_irqsave(&client->lock, flags);
347 		if (client->pkt_cnt++ == 0)
348 			mod_timer(&client->timer, jiffies +
349 				  msecs_to_jiffies(client->timeout_ms));
350 		spin_unlock_irqrestore(&client->lock, flags);
351 	}
352 
353 	mbox_send_message(client->chan, pkt);
354 	/* We can send next packet immediately, so just call txdone. */
355 	mbox_client_txdone(client->chan, 0);
356 
357 	return 0;
358 }
359 EXPORT_SYMBOL(cmdq_pkt_flush_async);
360 
361 struct cmdq_flush_completion {
362 	struct completion cmplt;
363 	bool err;
364 };
365 
366 static void cmdq_pkt_flush_cb(struct cmdq_cb_data data)
367 {
368 	struct cmdq_flush_completion *cmplt;
369 
370 	cmplt = (struct cmdq_flush_completion *)data.data;
371 	if (data.sta != CMDQ_CB_NORMAL)
372 		cmplt->err = true;
373 	else
374 		cmplt->err = false;
375 	complete(&cmplt->cmplt);
376 }
377 
378 int cmdq_pkt_flush(struct cmdq_pkt *pkt)
379 {
380 	struct cmdq_flush_completion cmplt;
381 	int err;
382 
383 	init_completion(&cmplt.cmplt);
384 	err = cmdq_pkt_flush_async(pkt, cmdq_pkt_flush_cb, &cmplt);
385 	if (err < 0)
386 		return err;
387 	wait_for_completion(&cmplt.cmplt);
388 
389 	return cmplt.err ? -EFAULT : 0;
390 }
391 EXPORT_SYMBOL(cmdq_pkt_flush);
392 
393 MODULE_LICENSE("GPL v2");
394