1 // SPDX-License-Identifier: ISC
2 /*
3  * Copyright (c) 2012-2015,2017 Qualcomm Atheros, Inc.
4  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
5  */
6 
7 #include <linux/types.h>
8 #include <linux/errno.h>
9 #include <linux/fs.h>
10 #include <linux/seq_file.h>
11 #include "wmi.h"
12 #include "wil6210.h"
13 #include "txrx.h"
14 #include "pmc.h"
15 
16 struct desc_alloc_info {
17 	dma_addr_t pa;
18 	void	  *va;
19 };
20 
wil_is_pmc_allocated(struct pmc_ctx * pmc)21 static int wil_is_pmc_allocated(struct pmc_ctx *pmc)
22 {
23 	return !!pmc->pring_va;
24 }
25 
wil_pmc_init(struct wil6210_priv * wil)26 void wil_pmc_init(struct wil6210_priv *wil)
27 {
28 	memset(&wil->pmc, 0, sizeof(struct pmc_ctx));
29 	mutex_init(&wil->pmc.lock);
30 }
31 
32 /* Allocate the physical ring (p-ring) and the required
33  * number of descriptors of required size.
34  * Initialize the descriptors as required by pmc dma.
35  * The descriptors' buffers dwords are initialized to hold
36  * dword's serial number in the lsw and reserved value
37  * PCM_DATA_INVALID_DW_VAL in the msw.
38  */
wil_pmc_alloc(struct wil6210_priv * wil,int num_descriptors,int descriptor_size)39 void wil_pmc_alloc(struct wil6210_priv *wil,
40 		   int num_descriptors,
41 		   int descriptor_size)
42 {
43 	u32 i;
44 	struct pmc_ctx *pmc = &wil->pmc;
45 	struct device *dev = wil_to_dev(wil);
46 	struct wil6210_vif *vif = ndev_to_vif(wil->main_ndev);
47 	struct wmi_pmc_cmd pmc_cmd = {0};
48 	int last_cmd_err = -ENOMEM;
49 
50 	mutex_lock(&pmc->lock);
51 
52 	if (wil_is_pmc_allocated(pmc)) {
53 		/* sanity check */
54 		wil_err(wil, "ERROR pmc is already allocated\n");
55 		goto no_release_err;
56 	}
57 	if ((num_descriptors <= 0) || (descriptor_size <= 0)) {
58 		wil_err(wil,
59 			"Invalid params num_descriptors(%d), descriptor_size(%d)\n",
60 			num_descriptors, descriptor_size);
61 		last_cmd_err = -EINVAL;
62 		goto no_release_err;
63 	}
64 
65 	if (num_descriptors > (1 << WIL_RING_SIZE_ORDER_MAX)) {
66 		wil_err(wil,
67 			"num_descriptors(%d) exceeds max ring size %d\n",
68 			num_descriptors, 1 << WIL_RING_SIZE_ORDER_MAX);
69 		last_cmd_err = -EINVAL;
70 		goto no_release_err;
71 	}
72 
73 	if (num_descriptors > INT_MAX / descriptor_size) {
74 		wil_err(wil,
75 			"Overflow in num_descriptors(%d)*descriptor_size(%d)\n",
76 			num_descriptors, descriptor_size);
77 		last_cmd_err = -EINVAL;
78 		goto no_release_err;
79 	}
80 
81 	pmc->num_descriptors = num_descriptors;
82 	pmc->descriptor_size = descriptor_size;
83 
84 	wil_dbg_misc(wil, "pmc_alloc: %d descriptors x %d bytes each\n",
85 		     num_descriptors, descriptor_size);
86 
87 	/* allocate descriptors info list in pmc context*/
88 	pmc->descriptors = kcalloc(num_descriptors,
89 				  sizeof(struct desc_alloc_info),
90 				  GFP_KERNEL);
91 	if (!pmc->descriptors) {
92 		wil_err(wil, "ERROR allocating pmc skb list\n");
93 		goto no_release_err;
94 	}
95 
96 	wil_dbg_misc(wil, "pmc_alloc: allocated descriptors info list %p\n",
97 		     pmc->descriptors);
98 
99 	/* Allocate pring buffer and descriptors.
100 	 * vring->va should be aligned on its size rounded up to power of 2
101 	 * This is granted by the dma_alloc_coherent.
102 	 *
103 	 * HW has limitation that all vrings addresses must share the same
104 	 * upper 16 msb bits part of 48 bits address. To workaround that,
105 	 * if we are using more than 32 bit addresses switch to 32 bit
106 	 * allocation before allocating vring memory.
107 	 *
108 	 * There's no check for the return value of dma_set_mask_and_coherent,
109 	 * since we assume if we were able to set the mask during
110 	 * initialization in this system it will not fail if we set it again
111 	 */
112 	if (wil->dma_addr_size > 32)
113 		dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
114 
115 	pmc->pring_va = dma_alloc_coherent(dev,
116 			sizeof(struct vring_tx_desc) * num_descriptors,
117 			&pmc->pring_pa,
118 			GFP_KERNEL);
119 
120 	if (wil->dma_addr_size > 32)
121 		dma_set_mask_and_coherent(dev,
122 					  DMA_BIT_MASK(wil->dma_addr_size));
123 
124 	wil_dbg_misc(wil,
125 		     "pmc_alloc: allocated pring %p => %pad. %zd x %d = total %zd bytes\n",
126 		     pmc->pring_va, &pmc->pring_pa,
127 		     sizeof(struct vring_tx_desc),
128 		     num_descriptors,
129 		     sizeof(struct vring_tx_desc) * num_descriptors);
130 
131 	if (!pmc->pring_va) {
132 		wil_err(wil, "ERROR allocating pmc pring\n");
133 		goto release_pmc_skb_list;
134 	}
135 
136 	/* initially, all descriptors are SW owned
137 	 * For Tx, Rx, and PMC, ownership bit is at the same location, thus
138 	 * we can use any
139 	 */
140 	for (i = 0; i < num_descriptors; i++) {
141 		struct vring_tx_desc *_d = &pmc->pring_va[i];
142 		struct vring_tx_desc dd = {}, *d = &dd;
143 		int j = 0;
144 
145 		pmc->descriptors[i].va = dma_alloc_coherent(dev,
146 			descriptor_size,
147 			&pmc->descriptors[i].pa,
148 			GFP_KERNEL);
149 
150 		if (unlikely(!pmc->descriptors[i].va)) {
151 			wil_err(wil, "ERROR allocating pmc descriptor %d", i);
152 			goto release_pmc_skbs;
153 		}
154 
155 		for (j = 0; j < descriptor_size / sizeof(u32); j++) {
156 			u32 *p = (u32 *)pmc->descriptors[i].va + j;
157 			*p = PCM_DATA_INVALID_DW_VAL | j;
158 		}
159 
160 		/* configure dma descriptor */
161 		d->dma.addr.addr_low =
162 			cpu_to_le32(lower_32_bits(pmc->descriptors[i].pa));
163 		d->dma.addr.addr_high =
164 			cpu_to_le16((u16)upper_32_bits(pmc->descriptors[i].pa));
165 		d->dma.status = 0; /* 0 = HW_OWNED */
166 		d->dma.length = cpu_to_le16(descriptor_size);
167 		d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
168 		*_d = *d;
169 	}
170 
171 	wil_dbg_misc(wil, "pmc_alloc: allocated successfully\n");
172 
173 	pmc_cmd.op = WMI_PMC_ALLOCATE;
174 	pmc_cmd.ring_size = cpu_to_le16(pmc->num_descriptors);
175 	pmc_cmd.mem_base = cpu_to_le64(pmc->pring_pa);
176 
177 	wil_dbg_misc(wil, "pmc_alloc: send WMI_PMC_CMD with ALLOCATE op\n");
178 	pmc->last_cmd_status = wmi_send(wil,
179 					WMI_PMC_CMDID,
180 					vif->mid,
181 					&pmc_cmd,
182 					sizeof(pmc_cmd));
183 	if (pmc->last_cmd_status) {
184 		wil_err(wil,
185 			"WMI_PMC_CMD with ALLOCATE op failed with status %d",
186 			pmc->last_cmd_status);
187 		goto release_pmc_skbs;
188 	}
189 
190 	mutex_unlock(&pmc->lock);
191 
192 	return;
193 
194 release_pmc_skbs:
195 	wil_err(wil, "exit on error: Releasing skbs...\n");
196 	for (i = 0; i < num_descriptors && pmc->descriptors[i].va; i++) {
197 		dma_free_coherent(dev,
198 				  descriptor_size,
199 				  pmc->descriptors[i].va,
200 				  pmc->descriptors[i].pa);
201 
202 		pmc->descriptors[i].va = NULL;
203 	}
204 	wil_err(wil, "exit on error: Releasing pring...\n");
205 
206 	dma_free_coherent(dev,
207 			  sizeof(struct vring_tx_desc) * num_descriptors,
208 			  pmc->pring_va,
209 			  pmc->pring_pa);
210 
211 	pmc->pring_va = NULL;
212 
213 release_pmc_skb_list:
214 	wil_err(wil, "exit on error: Releasing descriptors info list...\n");
215 	kfree(pmc->descriptors);
216 	pmc->descriptors = NULL;
217 
218 no_release_err:
219 	pmc->last_cmd_status = last_cmd_err;
220 	mutex_unlock(&pmc->lock);
221 }
222 
223 /* Traverse the p-ring and release all buffers.
224  * At the end release the p-ring memory
225  */
wil_pmc_free(struct wil6210_priv * wil,int send_pmc_cmd)226 void wil_pmc_free(struct wil6210_priv *wil, int send_pmc_cmd)
227 {
228 	struct pmc_ctx *pmc = &wil->pmc;
229 	struct device *dev = wil_to_dev(wil);
230 	struct wil6210_vif *vif = ndev_to_vif(wil->main_ndev);
231 	struct wmi_pmc_cmd pmc_cmd = {0};
232 
233 	mutex_lock(&pmc->lock);
234 
235 	pmc->last_cmd_status = 0;
236 
237 	if (!wil_is_pmc_allocated(pmc)) {
238 		wil_dbg_misc(wil,
239 			     "pmc_free: Error, can't free - not allocated\n");
240 		pmc->last_cmd_status = -EPERM;
241 		mutex_unlock(&pmc->lock);
242 		return;
243 	}
244 
245 	if (send_pmc_cmd) {
246 		wil_dbg_misc(wil, "send WMI_PMC_CMD with RELEASE op\n");
247 		pmc_cmd.op = WMI_PMC_RELEASE;
248 		pmc->last_cmd_status =
249 				wmi_send(wil, WMI_PMC_CMDID, vif->mid,
250 					 &pmc_cmd, sizeof(pmc_cmd));
251 		if (pmc->last_cmd_status) {
252 			wil_err(wil,
253 				"WMI_PMC_CMD with RELEASE op failed, status %d",
254 				pmc->last_cmd_status);
255 			/* There's nothing we can do with this error.
256 			 * Normally, it should never occur.
257 			 * Continue to freeing all memory allocated for pmc.
258 			 */
259 		}
260 	}
261 
262 	if (pmc->pring_va) {
263 		size_t buf_size = sizeof(struct vring_tx_desc) *
264 				  pmc->num_descriptors;
265 
266 		wil_dbg_misc(wil, "pmc_free: free pring va %p\n",
267 			     pmc->pring_va);
268 		dma_free_coherent(dev, buf_size, pmc->pring_va, pmc->pring_pa);
269 
270 		pmc->pring_va = NULL;
271 	} else {
272 		pmc->last_cmd_status = -ENOENT;
273 	}
274 
275 	if (pmc->descriptors) {
276 		int i;
277 
278 		for (i = 0;
279 		     i < pmc->num_descriptors && pmc->descriptors[i].va; i++) {
280 			dma_free_coherent(dev,
281 					  pmc->descriptor_size,
282 					  pmc->descriptors[i].va,
283 					  pmc->descriptors[i].pa);
284 			pmc->descriptors[i].va = NULL;
285 		}
286 		wil_dbg_misc(wil, "pmc_free: free descriptor info %d/%d\n", i,
287 			     pmc->num_descriptors);
288 		wil_dbg_misc(wil,
289 			     "pmc_free: free pmc descriptors info list %p\n",
290 			     pmc->descriptors);
291 		kfree(pmc->descriptors);
292 		pmc->descriptors = NULL;
293 	} else {
294 		pmc->last_cmd_status = -ENOENT;
295 	}
296 
297 	mutex_unlock(&pmc->lock);
298 }
299 
300 /* Status of the last operation requested via debugfs: alloc/free/read.
301  * 0 - success or negative errno
302  */
wil_pmc_last_cmd_status(struct wil6210_priv * wil)303 int wil_pmc_last_cmd_status(struct wil6210_priv *wil)
304 {
305 	wil_dbg_misc(wil, "pmc_last_cmd_status: status %d\n",
306 		     wil->pmc.last_cmd_status);
307 
308 	return wil->pmc.last_cmd_status;
309 }
310 
311 /* Read from required position up to the end of current descriptor,
312  * depends on descriptor size configured during alloc request.
313  */
wil_pmc_read(struct file * filp,char __user * buf,size_t count,loff_t * f_pos)314 ssize_t wil_pmc_read(struct file *filp, char __user *buf, size_t count,
315 		     loff_t *f_pos)
316 {
317 	struct wil6210_priv *wil = filp->private_data;
318 	struct pmc_ctx *pmc = &wil->pmc;
319 	size_t retval = 0;
320 	unsigned long long idx;
321 	loff_t offset;
322 	size_t pmc_size;
323 
324 	mutex_lock(&pmc->lock);
325 
326 	if (!wil_is_pmc_allocated(pmc)) {
327 		wil_err(wil, "error, pmc is not allocated!\n");
328 		pmc->last_cmd_status = -EPERM;
329 		mutex_unlock(&pmc->lock);
330 		return -EPERM;
331 	}
332 
333 	pmc_size = pmc->descriptor_size * pmc->num_descriptors;
334 
335 	wil_dbg_misc(wil,
336 		     "pmc_read: size %u, pos %lld\n",
337 		     (u32)count, *f_pos);
338 
339 	pmc->last_cmd_status = 0;
340 
341 	idx = *f_pos;
342 	do_div(idx, pmc->descriptor_size);
343 	offset = *f_pos - (idx * pmc->descriptor_size);
344 
345 	if (*f_pos >= pmc_size) {
346 		wil_dbg_misc(wil,
347 			     "pmc_read: reached end of pmc buf: %lld >= %u\n",
348 			     *f_pos, (u32)pmc_size);
349 		pmc->last_cmd_status = -ERANGE;
350 		goto out;
351 	}
352 
353 	wil_dbg_misc(wil,
354 		     "pmc_read: read from pos %lld (descriptor %llu, offset %llu) %zu bytes\n",
355 		     *f_pos, idx, offset, count);
356 
357 	/* if no errors, return the copied byte count */
358 	retval = simple_read_from_buffer(buf,
359 					 count,
360 					 &offset,
361 					 pmc->descriptors[idx].va,
362 					 pmc->descriptor_size);
363 	*f_pos += retval;
364 out:
365 	mutex_unlock(&pmc->lock);
366 
367 	return retval;
368 }
369 
wil_pmc_llseek(struct file * filp,loff_t off,int whence)370 loff_t wil_pmc_llseek(struct file *filp, loff_t off, int whence)
371 {
372 	loff_t newpos;
373 	struct wil6210_priv *wil = filp->private_data;
374 	struct pmc_ctx *pmc = &wil->pmc;
375 	size_t pmc_size;
376 
377 	mutex_lock(&pmc->lock);
378 
379 	if (!wil_is_pmc_allocated(pmc)) {
380 		wil_err(wil, "error, pmc is not allocated!\n");
381 		pmc->last_cmd_status = -EPERM;
382 		mutex_unlock(&pmc->lock);
383 		return -EPERM;
384 	}
385 
386 	pmc_size = pmc->descriptor_size * pmc->num_descriptors;
387 
388 	switch (whence) {
389 	case 0: /* SEEK_SET */
390 		newpos = off;
391 		break;
392 
393 	case 1: /* SEEK_CUR */
394 		newpos = filp->f_pos + off;
395 		break;
396 
397 	case 2: /* SEEK_END */
398 		newpos = pmc_size;
399 		break;
400 
401 	default: /* can't happen */
402 		newpos = -EINVAL;
403 		goto out;
404 	}
405 
406 	if (newpos < 0) {
407 		newpos = -EINVAL;
408 		goto out;
409 	}
410 	if (newpos > pmc_size)
411 		newpos = pmc_size;
412 
413 	filp->f_pos = newpos;
414 
415 out:
416 	mutex_unlock(&pmc->lock);
417 
418 	return newpos;
419 }
420 
wil_pmcring_read(struct seq_file * s,void * data)421 int wil_pmcring_read(struct seq_file *s, void *data)
422 {
423 	struct wil6210_priv *wil = s->private;
424 	struct pmc_ctx *pmc = &wil->pmc;
425 	size_t pmc_ring_size =
426 		sizeof(struct vring_rx_desc) * pmc->num_descriptors;
427 
428 	mutex_lock(&pmc->lock);
429 
430 	if (!wil_is_pmc_allocated(pmc)) {
431 		wil_err(wil, "error, pmc is not allocated!\n");
432 		pmc->last_cmd_status = -EPERM;
433 		mutex_unlock(&pmc->lock);
434 		return -EPERM;
435 	}
436 
437 	wil_dbg_misc(wil, "pmcring_read: size %zu\n", pmc_ring_size);
438 
439 	seq_write(s, pmc->pring_va, pmc_ring_size);
440 
441 	mutex_unlock(&pmc->lock);
442 
443 	return 0;
444 }
445