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  1/*
  2 * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
  3 *
  4 * This program is free software; you can redistribute it and/or modify it
  5 * under the terms and conditions of the GNU General Public License,
  6 * version 2, as published by the Free Software Foundation.
  7 *
  8 * This program is distributed in the hope it will be useful, but WITHOUT
  9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 11 * more details.
 12 *
 13 */
 14#include <linux/debugfs.h>
 15#include <linux/dma-mapping.h>
 16#include <linux/uaccess.h>
 17
 18#include <soc/tegra/bpmp.h>
 19#include <soc/tegra/bpmp-abi.h>
 20
 21struct seqbuf {
 22	char *buf;
 23	size_t pos;
 24	size_t size;
 25};
 26
 27static void seqbuf_init(struct seqbuf *seqbuf, void *buf, size_t size)
 28{
 29	seqbuf->buf = buf;
 30	seqbuf->size = size;
 31	seqbuf->pos = 0;
 32}
 33
 34static size_t seqbuf_avail(struct seqbuf *seqbuf)
 35{
 36	return seqbuf->pos < seqbuf->size ? seqbuf->size - seqbuf->pos : 0;
 37}
 38
 39static size_t seqbuf_status(struct seqbuf *seqbuf)
 40{
 41	return seqbuf->pos <= seqbuf->size ? 0 : -EOVERFLOW;
 42}
 43
 44static int seqbuf_eof(struct seqbuf *seqbuf)
 45{
 46	return seqbuf->pos >= seqbuf->size;
 47}
 48
 49static int seqbuf_read(struct seqbuf *seqbuf, void *buf, size_t nbyte)
 50{
 51	nbyte = min(nbyte, seqbuf_avail(seqbuf));
 52	memcpy(buf, seqbuf->buf + seqbuf->pos, nbyte);
 53	seqbuf->pos += nbyte;
 54	return seqbuf_status(seqbuf);
 55}
 56
 57static int seqbuf_read_u32(struct seqbuf *seqbuf, uint32_t *v)
 58{
 59	int err;
 60
 61	err = seqbuf_read(seqbuf, v, 4);
 62	*v = le32_to_cpu(*v);
 63	return err;
 64}
 65
 66static int seqbuf_read_str(struct seqbuf *seqbuf, const char **str)
 67{
 68	*str = seqbuf->buf + seqbuf->pos;
 69	seqbuf->pos += strnlen(*str, seqbuf_avail(seqbuf));
 70	seqbuf->pos++;
 71	return seqbuf_status(seqbuf);
 72}
 73
 74static void seqbuf_seek(struct seqbuf *seqbuf, ssize_t offset)
 75{
 76	seqbuf->pos += offset;
 77}
 78
 79/* map filename in Linux debugfs to corresponding entry in BPMP */
 80static const char *get_filename(struct tegra_bpmp *bpmp,
 81				const struct file *file, char *buf, int size)
 82{
 83	char root_path_buf[512];
 84	const char *root_path;
 85	const char *filename;
 86	size_t root_len;
 87
 88	root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
 89				sizeof(root_path_buf));
 90	if (IS_ERR(root_path))
 91		return NULL;
 92
 93	root_len = strlen(root_path);
 94
 95	filename = dentry_path(file->f_path.dentry, buf, size);
 96	if (IS_ERR(filename))
 97		return NULL;
 98
 99	if (strlen(filename) < root_len ||
100			strncmp(filename, root_path, root_len))
101		return NULL;
102
103	filename += root_len;
104
105	return filename;
106}
107
108static int mrq_debugfs_read(struct tegra_bpmp *bpmp,
109			    dma_addr_t name, size_t sz_name,
110			    dma_addr_t data, size_t sz_data,
111			    size_t *nbytes)
112{
113	struct mrq_debugfs_request req = {
114		.cmd = cpu_to_le32(CMD_DEBUGFS_READ),
115		.fop = {
116			.fnameaddr = cpu_to_le32((uint32_t)name),
117			.fnamelen = cpu_to_le32((uint32_t)sz_name),
118			.dataaddr = cpu_to_le32((uint32_t)data),
119			.datalen = cpu_to_le32((uint32_t)sz_data),
120		},
121	};
122	struct mrq_debugfs_response resp;
123	struct tegra_bpmp_message msg = {
124		.mrq = MRQ_DEBUGFS,
125		.tx = {
126			.data = &req,
127			.size = sizeof(req),
128		},
129		.rx = {
130			.data = &resp,
131			.size = sizeof(resp),
132		},
133	};
134	int err;
135
136	err = tegra_bpmp_transfer(bpmp, &msg);
137	if (err < 0)
138		return err;
139
140	*nbytes = (size_t)resp.fop.nbytes;
141
142	return 0;
143}
144
145static int mrq_debugfs_write(struct tegra_bpmp *bpmp,
146			     dma_addr_t name, size_t sz_name,
147			     dma_addr_t data, size_t sz_data)
148{
149	const struct mrq_debugfs_request req = {
150		.cmd = cpu_to_le32(CMD_DEBUGFS_WRITE),
151		.fop = {
152			.fnameaddr = cpu_to_le32((uint32_t)name),
153			.fnamelen = cpu_to_le32((uint32_t)sz_name),
154			.dataaddr = cpu_to_le32((uint32_t)data),
155			.datalen = cpu_to_le32((uint32_t)sz_data),
156		},
157	};
158	struct tegra_bpmp_message msg = {
159		.mrq = MRQ_DEBUGFS,
160		.tx = {
161			.data = &req,
162			.size = sizeof(req),
163		},
164	};
165
166	return tegra_bpmp_transfer(bpmp, &msg);
167}
168
169static int mrq_debugfs_dumpdir(struct tegra_bpmp *bpmp, dma_addr_t addr,
170			       size_t size, size_t *nbytes)
171{
172	const struct mrq_debugfs_request req = {
173		.cmd = cpu_to_le32(CMD_DEBUGFS_DUMPDIR),
174		.dumpdir = {
175			.dataaddr = cpu_to_le32((uint32_t)addr),
176			.datalen = cpu_to_le32((uint32_t)size),
177		},
178	};
179	struct mrq_debugfs_response resp;
180	struct tegra_bpmp_message msg = {
181		.mrq = MRQ_DEBUGFS,
182		.tx = {
183			.data = &req,
184			.size = sizeof(req),
185		},
186		.rx = {
187			.data = &resp,
188			.size = sizeof(resp),
189		},
190	};
191	int err;
192
193	err = tegra_bpmp_transfer(bpmp, &msg);
194	if (err < 0)
195		return err;
196
197	*nbytes = (size_t)resp.dumpdir.nbytes;
198
199	return 0;
200}
201
202static int debugfs_show(struct seq_file *m, void *p)
203{
204	struct file *file = m->private;
205	struct inode *inode = file_inode(file);
206	struct tegra_bpmp *bpmp = inode->i_private;
207	const size_t datasize = m->size;
208	const size_t namesize = SZ_256;
209	void *datavirt, *namevirt;
210	dma_addr_t dataphys, namephys;
211	char buf[256];
212	const char *filename;
213	size_t len, nbytes;
214	int ret;
215
216	filename = get_filename(bpmp, file, buf, sizeof(buf));
217	if (!filename)
218		return -ENOENT;
219
220	namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
221				      GFP_KERNEL | GFP_DMA32);
222	if (!namevirt)
223		return -ENOMEM;
224
225	datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
226				      GFP_KERNEL | GFP_DMA32);
227	if (!datavirt) {
228		ret = -ENOMEM;
229		goto free_namebuf;
230	}
231
232	len = strlen(filename);
233	strncpy(namevirt, filename, namesize);
234
235	ret = mrq_debugfs_read(bpmp, namephys, len, dataphys, datasize,
236			       &nbytes);
237
238	if (!ret)
239		seq_write(m, datavirt, nbytes);
240
241	dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
242free_namebuf:
243	dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
244
245	return ret;
246}
247
248static int debugfs_open(struct inode *inode, struct file *file)
249{
250	return single_open_size(file, debugfs_show, file, SZ_128K);
251}
252
253static ssize_t debugfs_store(struct file *file, const char __user *buf,
254		size_t count, loff_t *f_pos)
255{
256	struct inode *inode = file_inode(file);
257	struct tegra_bpmp *bpmp = inode->i_private;
258	const size_t datasize = count;
259	const size_t namesize = SZ_256;
260	void *datavirt, *namevirt;
261	dma_addr_t dataphys, namephys;
262	char fnamebuf[256];
263	const char *filename;
264	size_t len;
265	int ret;
266
267	filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
268	if (!filename)
269		return -ENOENT;
270
271	namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
272				      GFP_KERNEL | GFP_DMA32);
273	if (!namevirt)
274		return -ENOMEM;
275
276	datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
277				      GFP_KERNEL | GFP_DMA32);
278	if (!datavirt) {
279		ret = -ENOMEM;
280		goto free_namebuf;
281	}
282
283	len = strlen(filename);
284	strncpy(namevirt, filename, namesize);
285
286	if (copy_from_user(datavirt, buf, count)) {
287		ret = -EFAULT;
288		goto free_databuf;
289	}
290
291	ret = mrq_debugfs_write(bpmp, namephys, len, dataphys,
292				count);
293
294free_databuf:
295	dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
296free_namebuf:
297	dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
298
299	return ret ?: count;
300}
301
302static const struct file_operations debugfs_fops = {
303	.open		= debugfs_open,
304	.read		= seq_read,
305	.llseek		= seq_lseek,
306	.write		= debugfs_store,
307	.release	= single_release,
308};
309
310static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf,
311			     struct dentry *parent, uint32_t depth)
312{
313	int err;
314	uint32_t d, t;
315	const char *name;
316	struct dentry *dentry;
317
318	while (!seqbuf_eof(seqbuf)) {
319		err = seqbuf_read_u32(seqbuf, &d);
320		if (err < 0)
321			return err;
322
323		if (d < depth) {
324			seqbuf_seek(seqbuf, -4);
325			/* go up a level */
326			return 0;
327		} else if (d != depth) {
328			/* malformed data received from BPMP */
329			return -EIO;
330		}
331
332		err = seqbuf_read_u32(seqbuf, &t);
333		if (err < 0)
334			return err;
335		err = seqbuf_read_str(seqbuf, &name);
336		if (err < 0)
337			return err;
338
339		if (t & DEBUGFS_S_ISDIR) {
340			dentry = debugfs_create_dir(name, parent);
341			if (!dentry)
342				return -ENOMEM;
343			err = bpmp_populate_dir(bpmp, seqbuf, dentry, depth+1);
344			if (err < 0)
345				return err;
346		} else {
347			umode_t mode;
348
349			mode = t & DEBUGFS_S_IRUSR ? S_IRUSR : 0;
350			mode |= t & DEBUGFS_S_IWUSR ? S_IWUSR : 0;
351			dentry = debugfs_create_file(name, mode,
352						     parent, bpmp,
353						     &debugfs_fops);
354			if (!dentry)
355				return -ENOMEM;
356		}
357	}
358
359	return 0;
360}
361
362static int create_debugfs_mirror(struct tegra_bpmp *bpmp, void *buf,
363				 size_t bufsize, struct dentry *root)
364{
365	struct seqbuf seqbuf;
366	int err;
367
368	bpmp->debugfs_mirror = debugfs_create_dir("debug", root);
369	if (!bpmp->debugfs_mirror)
370		return -ENOMEM;
371
372	seqbuf_init(&seqbuf, buf, bufsize);
373	err = bpmp_populate_dir(bpmp, &seqbuf, bpmp->debugfs_mirror, 0);
374	if (err < 0) {
375		debugfs_remove_recursive(bpmp->debugfs_mirror);
376		bpmp->debugfs_mirror = NULL;
377	}
378
379	return err;
380}
381
382static int mrq_is_supported(struct tegra_bpmp *bpmp, unsigned int mrq)
383{
384	struct mrq_query_abi_request req = { .mrq = cpu_to_le32(mrq) };
385	struct mrq_query_abi_response resp;
386	struct tegra_bpmp_message msg = {
387		.mrq = MRQ_QUERY_ABI,
388		.tx = {
389			.data = &req,
390			.size = sizeof(req),
391		},
392		.rx = {
393			.data = &resp,
394			.size = sizeof(resp),
395		},
396	};
397	int ret;
398
399	ret = tegra_bpmp_transfer(bpmp, &msg);
400	if (ret < 0) {
401		/* something went wrong; assume not supported */
402		dev_warn(bpmp->dev, "tegra_bpmp_transfer failed (%d)\n", ret);
403		return 0;
404	}
405
406	return resp.status ? 0 : 1;
407}
408
409int tegra_bpmp_init_debugfs(struct tegra_bpmp *bpmp)
410{
411	dma_addr_t phys;
412	void *virt;
413	const size_t sz = SZ_256K;
414	size_t nbytes;
415	int ret;
416	struct dentry *root;
417
418	if (!mrq_is_supported(bpmp, MRQ_DEBUGFS))
419		return 0;
420
421	root = debugfs_create_dir("bpmp", NULL);
422	if (!root)
423		return -ENOMEM;
424
425	virt = dma_alloc_coherent(bpmp->dev, sz, &phys,
426				  GFP_KERNEL | GFP_DMA32);
427	if (!virt) {
428		ret = -ENOMEM;
429		goto out;
430	}
431
432	ret = mrq_debugfs_dumpdir(bpmp, phys, sz, &nbytes);
433	if (ret < 0)
434		goto free;
435
436	ret = create_debugfs_mirror(bpmp, virt, nbytes, root);
437free:
438	dma_free_coherent(bpmp->dev, sz, virt, phys);
439out:
440	if (ret < 0)
441		debugfs_remove(root);
442
443	return ret;
444}
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
  4 */
  5#include <linux/debugfs.h>
  6#include <linux/dma-mapping.h>
  7#include <linux/slab.h>
  8#include <linux/uaccess.h>
  9
 10#include <soc/tegra/bpmp.h>
 11#include <soc/tegra/bpmp-abi.h>
 12
 13static DEFINE_MUTEX(bpmp_debug_lock);
 14
 15struct seqbuf {
 16	char *buf;
 17	size_t pos;
 18	size_t size;
 19};
 20
 21static void seqbuf_init(struct seqbuf *seqbuf, void *buf, size_t size)
 22{
 23	seqbuf->buf = buf;
 24	seqbuf->size = size;
 25	seqbuf->pos = 0;
 26}
 27
 28static size_t seqbuf_avail(struct seqbuf *seqbuf)
 29{
 30	return seqbuf->pos < seqbuf->size ? seqbuf->size - seqbuf->pos : 0;
 31}
 32
 33static size_t seqbuf_status(struct seqbuf *seqbuf)
 34{
 35	return seqbuf->pos <= seqbuf->size ? 0 : -EOVERFLOW;
 36}
 37
 38static int seqbuf_eof(struct seqbuf *seqbuf)
 39{
 40	return seqbuf->pos >= seqbuf->size;
 41}
 42
 43static int seqbuf_read(struct seqbuf *seqbuf, void *buf, size_t nbyte)
 44{
 45	nbyte = min(nbyte, seqbuf_avail(seqbuf));
 46	memcpy(buf, seqbuf->buf + seqbuf->pos, nbyte);
 47	seqbuf->pos += nbyte;
 48	return seqbuf_status(seqbuf);
 49}
 50
 51static int seqbuf_read_u32(struct seqbuf *seqbuf, u32 *v)
 52{
 53	return seqbuf_read(seqbuf, v, 4);
 54}
 55
 56static int seqbuf_read_str(struct seqbuf *seqbuf, const char **str)
 57{
 58	*str = seqbuf->buf + seqbuf->pos;
 59	seqbuf->pos += strnlen(*str, seqbuf_avail(seqbuf));
 60	seqbuf->pos++;
 61	return seqbuf_status(seqbuf);
 62}
 63
 64static void seqbuf_seek(struct seqbuf *seqbuf, ssize_t offset)
 65{
 66	seqbuf->pos += offset;
 67}
 68
 69/* map filename in Linux debugfs to corresponding entry in BPMP */
 70static const char *get_filename(struct tegra_bpmp *bpmp,
 71				const struct file *file, char *buf, int size)
 72{
 73	const char *root_path, *filename = NULL;
 74	char *root_path_buf;
 75	size_t root_len;
 76	size_t root_path_buf_len = 512;
 77
 78	root_path_buf = kzalloc(root_path_buf_len, GFP_KERNEL);
 79	if (!root_path_buf)
 80		goto out;
 81
 82	root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
 83				root_path_buf_len);
 84	if (IS_ERR(root_path))
 85		goto out;
 86
 87	root_len = strlen(root_path);
 88
 89	filename = dentry_path(file->f_path.dentry, buf, size);
 90	if (IS_ERR(filename)) {
 91		filename = NULL;
 92		goto out;
 93	}
 94
 95	if (strlen(filename) < root_len || strncmp(filename, root_path, root_len)) {
 96		filename = NULL;
 97		goto out;
 98	}
 99
100	filename += root_len;
101
102out:
103	kfree(root_path_buf);
104	return filename;
105}
106
107static int mrq_debug_open(struct tegra_bpmp *bpmp, const char *name,
108			  u32 *fd, u32 *len, bool write)
109{
110	struct mrq_debug_request req = {
111		.cmd = write ? CMD_DEBUG_OPEN_WO : CMD_DEBUG_OPEN_RO,
112	};
113	struct mrq_debug_response resp;
114	struct tegra_bpmp_message msg = {
115		.mrq = MRQ_DEBUG,
116		.tx = {
117			.data = &req,
118			.size = sizeof(req),
119		},
120		.rx = {
121			.data = &resp,
122			.size = sizeof(resp),
123		},
124	};
125	ssize_t sz_name;
126	int err = 0;
127
128	sz_name = strscpy(req.fop.name, name, sizeof(req.fop.name));
129	if (sz_name < 0) {
130		pr_err("File name too large: %s\n", name);
131		return -EINVAL;
132	}
133
134	err = tegra_bpmp_transfer(bpmp, &msg);
135	if (err < 0)
136		return err;
137	else if (msg.rx.ret < 0)
138		return -EINVAL;
139
140	*len = resp.fop.datalen;
141	*fd = resp.fop.fd;
142
143	return 0;
144}
145
146static int mrq_debug_close(struct tegra_bpmp *bpmp, u32 fd)
147{
148	struct mrq_debug_request req = {
149		.cmd = CMD_DEBUG_CLOSE,
150		.frd = {
151			.fd = fd,
152		},
153	};
154	struct mrq_debug_response resp;
155	struct tegra_bpmp_message msg = {
156		.mrq = MRQ_DEBUG,
157		.tx = {
158			.data = &req,
159			.size = sizeof(req),
160		},
161		.rx = {
162			.data = &resp,
163			.size = sizeof(resp),
164		},
165	};
166	int err = 0;
167
168	err = tegra_bpmp_transfer(bpmp, &msg);
169	if (err < 0)
170		return err;
171	else if (msg.rx.ret < 0)
172		return -EINVAL;
173
174	return 0;
175}
176
177static int mrq_debug_read(struct tegra_bpmp *bpmp, const char *name,
178			  char *data, size_t sz_data, u32 *nbytes)
179{
180	struct mrq_debug_request req = {
181		.cmd = CMD_DEBUG_READ,
182	};
183	struct mrq_debug_response resp;
184	struct tegra_bpmp_message msg = {
185		.mrq = MRQ_DEBUG,
186		.tx = {
187			.data = &req,
188			.size = sizeof(req),
189		},
190		.rx = {
191			.data = &resp,
192			.size = sizeof(resp),
193		},
194	};
195	u32 fd = 0, len = 0;
196	int remaining, err;
197
198	mutex_lock(&bpmp_debug_lock);
199	err = mrq_debug_open(bpmp, name, &fd, &len, 0);
200	if (err)
201		goto out;
202
203	if (len > sz_data) {
204		err = -EFBIG;
205		goto close;
206	}
207
208	req.frd.fd = fd;
209	remaining = len;
210
211	while (remaining > 0) {
212		err = tegra_bpmp_transfer(bpmp, &msg);
213		if (err < 0) {
214			goto close;
215		} else if (msg.rx.ret < 0) {
216			err = -EINVAL;
217			goto close;
218		}
219
220		if (resp.frd.readlen > remaining) {
221			pr_err("%s: read data length invalid\n", __func__);
222			err = -EINVAL;
223			goto close;
224		}
225
226		memcpy(data, resp.frd.data, resp.frd.readlen);
227		data += resp.frd.readlen;
228		remaining -= resp.frd.readlen;
229	}
230
231	*nbytes = len;
232
233close:
234	err = mrq_debug_close(bpmp, fd);
235out:
236	mutex_unlock(&bpmp_debug_lock);
237	return err;
238}
239
240static int mrq_debug_write(struct tegra_bpmp *bpmp, const char *name,
241			   uint8_t *data, size_t sz_data)
242{
243	struct mrq_debug_request req = {
244		.cmd = CMD_DEBUG_WRITE
245	};
246	struct mrq_debug_response resp;
247	struct tegra_bpmp_message msg = {
248		.mrq = MRQ_DEBUG,
249		.tx = {
250			.data = &req,
251			.size = sizeof(req),
252		},
253		.rx = {
254			.data = &resp,
255			.size = sizeof(resp),
256		},
257	};
258	u32 fd = 0, len = 0;
259	size_t remaining;
260	int err;
261
262	mutex_lock(&bpmp_debug_lock);
263	err = mrq_debug_open(bpmp, name, &fd, &len, 1);
264	if (err)
265		goto out;
266
267	if (sz_data > len) {
268		err = -EINVAL;
269		goto close;
270	}
271
272	req.fwr.fd = fd;
273	remaining = sz_data;
274
275	while (remaining > 0) {
276		len = min(remaining, sizeof(req.fwr.data));
277		memcpy(req.fwr.data, data, len);
278		req.fwr.datalen = len;
279
280		err = tegra_bpmp_transfer(bpmp, &msg);
281		if (err < 0) {
282			goto close;
283		} else if (msg.rx.ret < 0) {
284			err = -EINVAL;
285			goto close;
286		}
287
288		data += req.fwr.datalen;
289		remaining -= req.fwr.datalen;
290	}
291
292close:
293	err = mrq_debug_close(bpmp, fd);
294out:
295	mutex_unlock(&bpmp_debug_lock);
296	return err;
297}
298
299static int bpmp_debug_show(struct seq_file *m, void *p)
300{
301	struct file *file = m->private;
302	struct inode *inode = file_inode(file);
303	struct tegra_bpmp *bpmp = inode->i_private;
304	char fnamebuf[256];
305	const char *filename;
306	struct mrq_debug_request req = {
307		.cmd = CMD_DEBUG_READ,
308	};
309	struct mrq_debug_response resp;
310	struct tegra_bpmp_message msg = {
311		.mrq = MRQ_DEBUG,
312		.tx = {
313			.data = &req,
314			.size = sizeof(req),
315		},
316		.rx = {
317			.data = &resp,
318			.size = sizeof(resp),
319		},
320	};
321	u32 fd = 0, len = 0;
322	int remaining, err;
323
324	filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
325	if (!filename)
326		return -ENOENT;
327
328	mutex_lock(&bpmp_debug_lock);
329	err = mrq_debug_open(bpmp, filename, &fd, &len, 0);
330	if (err)
331		goto out;
332
333	req.frd.fd = fd;
334	remaining = len;
335
336	while (remaining > 0) {
337		err = tegra_bpmp_transfer(bpmp, &msg);
338		if (err < 0) {
339			goto close;
340		} else if (msg.rx.ret < 0) {
341			err = -EINVAL;
342			goto close;
343		}
344
345		if (resp.frd.readlen > remaining) {
346			pr_err("%s: read data length invalid\n", __func__);
347			err = -EINVAL;
348			goto close;
349		}
350
351		seq_write(m, resp.frd.data, resp.frd.readlen);
352		remaining -= resp.frd.readlen;
353	}
354
355close:
356	err = mrq_debug_close(bpmp, fd);
357out:
358	mutex_unlock(&bpmp_debug_lock);
359	return err;
360}
361
362static ssize_t bpmp_debug_store(struct file *file, const char __user *buf,
363		size_t count, loff_t *f_pos)
364{
365	struct inode *inode = file_inode(file);
366	struct tegra_bpmp *bpmp = inode->i_private;
367	char *databuf = NULL;
368	char fnamebuf[256];
369	const char *filename;
370	ssize_t err;
371
372	filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
373	if (!filename)
374		return -ENOENT;
375
376	databuf = memdup_user(buf, count);
377	if (IS_ERR(databuf))
378		return PTR_ERR(databuf);
379
380	err = mrq_debug_write(bpmp, filename, databuf, count);
381	kfree(databuf);
382
383	return err ?: count;
384}
385
386static int bpmp_debug_open(struct inode *inode, struct file *file)
387{
388	return single_open_size(file, bpmp_debug_show, file, SZ_256K);
389}
390
391static const struct file_operations bpmp_debug_fops = {
392	.open		= bpmp_debug_open,
393	.read		= seq_read,
394	.llseek		= seq_lseek,
395	.write		= bpmp_debug_store,
396	.release	= single_release,
397};
398
399static int bpmp_populate_debugfs_inband(struct tegra_bpmp *bpmp,
400					struct dentry *parent,
401					char *ppath)
402{
403	const size_t pathlen = SZ_256;
404	const size_t bufsize = SZ_16K;
405	struct dentry *dentry;
406	u32 dsize, attrs = 0;
407	struct seqbuf seqbuf;
408	char *buf, *pathbuf;
409	const char *name;
410	int err = 0;
411
412	if (!bpmp || !parent || !ppath)
413		return -EINVAL;
414
415	buf = kmalloc(bufsize, GFP_KERNEL);
416	if (!buf)
417		return -ENOMEM;
418
419	pathbuf = kzalloc(pathlen, GFP_KERNEL);
420	if (!pathbuf) {
421		kfree(buf);
422		return -ENOMEM;
423	}
424
425	err = mrq_debug_read(bpmp, ppath, buf, bufsize, &dsize);
426	if (err)
427		goto out;
428
429	seqbuf_init(&seqbuf, buf, dsize);
430
431	while (!seqbuf_eof(&seqbuf)) {
432		err = seqbuf_read_u32(&seqbuf, &attrs);
433		if (err)
434			goto out;
435
436		err = seqbuf_read_str(&seqbuf, &name);
437		if (err < 0)
438			goto out;
439
440		if (attrs & DEBUGFS_S_ISDIR) {
441			size_t len;
442
443			dentry = debugfs_create_dir(name, parent);
444			if (IS_ERR(dentry)) {
445				err = PTR_ERR(dentry);
446				goto out;
447			}
448
449			len = snprintf(pathbuf, pathlen, "%s%s/", ppath, name);
450			if (len >= pathlen) {
451				err = -EINVAL;
452				goto out;
453			}
454
455			err = bpmp_populate_debugfs_inband(bpmp, dentry,
456							   pathbuf);
457			if (err < 0)
458				goto out;
459		} else {
460			umode_t mode;
461
462			mode = attrs & DEBUGFS_S_IRUSR ? 0400 : 0;
463			mode |= attrs & DEBUGFS_S_IWUSR ? 0200 : 0;
464			dentry = debugfs_create_file(name, mode, parent, bpmp,
465						     &bpmp_debug_fops);
466			if (IS_ERR(dentry)) {
467				err = -ENOMEM;
468				goto out;
469			}
470		}
471	}
472
473out:
474	kfree(pathbuf);
475	kfree(buf);
476
477	return err;
478}
479
480static int mrq_debugfs_read(struct tegra_bpmp *bpmp,
481			    dma_addr_t name, size_t sz_name,
482			    dma_addr_t data, size_t sz_data,
483			    size_t *nbytes)
484{
485	struct mrq_debugfs_request req = {
486		.cmd = CMD_DEBUGFS_READ,
487		.fop = {
488			.fnameaddr = (u32)name,
489			.fnamelen = (u32)sz_name,
490			.dataaddr = (u32)data,
491			.datalen = (u32)sz_data,
492		},
493	};
494	struct mrq_debugfs_response resp;
495	struct tegra_bpmp_message msg = {
496		.mrq = MRQ_DEBUGFS,
497		.tx = {
498			.data = &req,
499			.size = sizeof(req),
500		},
501		.rx = {
502			.data = &resp,
503			.size = sizeof(resp),
504		},
505	};
506	int err;
507
508	err = tegra_bpmp_transfer(bpmp, &msg);
509	if (err < 0)
510		return err;
511	else if (msg.rx.ret < 0)
512		return -EINVAL;
513
514	*nbytes = (size_t)resp.fop.nbytes;
515
516	return 0;
517}
518
519static int mrq_debugfs_write(struct tegra_bpmp *bpmp,
520			     dma_addr_t name, size_t sz_name,
521			     dma_addr_t data, size_t sz_data)
522{
523	const struct mrq_debugfs_request req = {
524		.cmd = CMD_DEBUGFS_WRITE,
525		.fop = {
526			.fnameaddr = (u32)name,
527			.fnamelen = (u32)sz_name,
528			.dataaddr = (u32)data,
529			.datalen = (u32)sz_data,
530		},
531	};
532	struct tegra_bpmp_message msg = {
533		.mrq = MRQ_DEBUGFS,
534		.tx = {
535			.data = &req,
536			.size = sizeof(req),
537		},
538	};
539
540	return tegra_bpmp_transfer(bpmp, &msg);
541}
542
543static int mrq_debugfs_dumpdir(struct tegra_bpmp *bpmp, dma_addr_t addr,
544			       size_t size, size_t *nbytes)
545{
546	const struct mrq_debugfs_request req = {
547		.cmd = CMD_DEBUGFS_DUMPDIR,
548		.dumpdir = {
549			.dataaddr = (u32)addr,
550			.datalen = (u32)size,
551		},
552	};
553	struct mrq_debugfs_response resp;
554	struct tegra_bpmp_message msg = {
555		.mrq = MRQ_DEBUGFS,
556		.tx = {
557			.data = &req,
558			.size = sizeof(req),
559		},
560		.rx = {
561			.data = &resp,
562			.size = sizeof(resp),
563		},
564	};
565	int err;
566
567	err = tegra_bpmp_transfer(bpmp, &msg);
568	if (err < 0)
569		return err;
570	else if (msg.rx.ret < 0)
571		return -EINVAL;
572
573	*nbytes = (size_t)resp.dumpdir.nbytes;
574
575	return 0;
576}
577
578static int debugfs_show(struct seq_file *m, void *p)
579{
580	struct file *file = m->private;
581	struct inode *inode = file_inode(file);
582	struct tegra_bpmp *bpmp = inode->i_private;
583	const size_t datasize = m->size;
584	const size_t namesize = SZ_256;
585	void *datavirt, *namevirt;
586	dma_addr_t dataphys, namephys;
587	char buf[256];
588	const char *filename;
589	size_t len, nbytes;
590	int err;
591
592	filename = get_filename(bpmp, file, buf, sizeof(buf));
593	if (!filename)
594		return -ENOENT;
595
596	namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
597				      GFP_KERNEL | GFP_DMA32);
598	if (!namevirt)
599		return -ENOMEM;
600
601	datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
602				      GFP_KERNEL | GFP_DMA32);
603	if (!datavirt) {
604		err = -ENOMEM;
605		goto free_namebuf;
606	}
607
608	len = strlen(filename);
609	strncpy(namevirt, filename, namesize);
610
611	err = mrq_debugfs_read(bpmp, namephys, len, dataphys, datasize,
612			       &nbytes);
613
614	if (!err)
615		seq_write(m, datavirt, nbytes);
616
617	dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
618free_namebuf:
619	dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
620
621	return err;
622}
623
624static int debugfs_open(struct inode *inode, struct file *file)
625{
626	return single_open_size(file, debugfs_show, file, SZ_128K);
627}
628
629static ssize_t debugfs_store(struct file *file, const char __user *buf,
630		size_t count, loff_t *f_pos)
631{
632	struct inode *inode = file_inode(file);
633	struct tegra_bpmp *bpmp = inode->i_private;
634	const size_t datasize = count;
635	const size_t namesize = SZ_256;
636	void *datavirt, *namevirt;
637	dma_addr_t dataphys, namephys;
638	char fnamebuf[256];
639	const char *filename;
640	size_t len;
641	int err;
642
643	filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
644	if (!filename)
645		return -ENOENT;
646
647	namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
648				      GFP_KERNEL | GFP_DMA32);
649	if (!namevirt)
650		return -ENOMEM;
651
652	datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
653				      GFP_KERNEL | GFP_DMA32);
654	if (!datavirt) {
655		err = -ENOMEM;
656		goto free_namebuf;
657	}
658
659	len = strlen(filename);
660	strncpy(namevirt, filename, namesize);
661
662	if (copy_from_user(datavirt, buf, count)) {
663		err = -EFAULT;
664		goto free_databuf;
665	}
666
667	err = mrq_debugfs_write(bpmp, namephys, len, dataphys,
668				count);
669
670free_databuf:
671	dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
672free_namebuf:
673	dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
674
675	return err ?: count;
676}
677
678static const struct file_operations debugfs_fops = {
679	.open		= debugfs_open,
680	.read		= seq_read,
681	.llseek		= seq_lseek,
682	.write		= debugfs_store,
683	.release	= single_release,
684};
685
686static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf,
687			     struct dentry *parent, u32 depth)
688{
689	int err;
690	u32 d, t;
691	const char *name;
692	struct dentry *dentry;
693
694	while (!seqbuf_eof(seqbuf)) {
695		err = seqbuf_read_u32(seqbuf, &d);
696		if (err < 0)
697			return err;
698
699		if (d < depth) {
700			seqbuf_seek(seqbuf, -4);
701			/* go up a level */
702			return 0;
703		} else if (d != depth) {
704			/* malformed data received from BPMP */
705			return -EIO;
706		}
707
708		err = seqbuf_read_u32(seqbuf, &t);
709		if (err < 0)
710			return err;
711		err = seqbuf_read_str(seqbuf, &name);
712		if (err < 0)
713			return err;
714
715		if (t & DEBUGFS_S_ISDIR) {
716			dentry = debugfs_create_dir(name, parent);
717			if (IS_ERR(dentry))
718				return -ENOMEM;
719			err = bpmp_populate_dir(bpmp, seqbuf, dentry, depth+1);
720			if (err < 0)
721				return err;
722		} else {
723			umode_t mode;
724
725			mode = t & DEBUGFS_S_IRUSR ? S_IRUSR : 0;
726			mode |= t & DEBUGFS_S_IWUSR ? S_IWUSR : 0;
727			dentry = debugfs_create_file(name, mode,
728						     parent, bpmp,
729						     &debugfs_fops);
730			if (IS_ERR(dentry))
731				return -ENOMEM;
732		}
733	}
734
735	return 0;
736}
737
738static int bpmp_populate_debugfs_shmem(struct tegra_bpmp *bpmp)
739{
740	struct seqbuf seqbuf;
741	const size_t sz = SZ_512K;
742	dma_addr_t phys;
743	size_t nbytes;
744	void *virt;
745	int err;
746
747	virt = dma_alloc_coherent(bpmp->dev, sz, &phys,
748				  GFP_KERNEL | GFP_DMA32);
749	if (!virt)
750		return -ENOMEM;
751
752	err = mrq_debugfs_dumpdir(bpmp, phys, sz, &nbytes);
753	if (err < 0) {
754		goto free;
755	} else if (nbytes > sz) {
756		err = -EINVAL;
757		goto free;
758	}
759
760	seqbuf_init(&seqbuf, virt, nbytes);
761	err = bpmp_populate_dir(bpmp, &seqbuf, bpmp->debugfs_mirror, 0);
762free:
763	dma_free_coherent(bpmp->dev, sz, virt, phys);
764
765	return err;
766}
767
768int tegra_bpmp_init_debugfs(struct tegra_bpmp *bpmp)
769{
770	struct dentry *root;
771	bool inband;
772	int err;
773
774	inband = tegra_bpmp_mrq_is_supported(bpmp, MRQ_DEBUG);
775
776	if (!inband && !tegra_bpmp_mrq_is_supported(bpmp, MRQ_DEBUGFS))
777		return 0;
778
779	root = debugfs_create_dir("bpmp", NULL);
780	if (IS_ERR(root))
781		return -ENOMEM;
782
783	bpmp->debugfs_mirror = debugfs_create_dir("debug", root);
784	if (IS_ERR(bpmp->debugfs_mirror)) {
785		err = -ENOMEM;
786		goto out;
787	}
788
789	if (inband)
790		err = bpmp_populate_debugfs_inband(bpmp, bpmp->debugfs_mirror,
791						   "/");
792	else
793		err = bpmp_populate_debugfs_shmem(bpmp);
794
795out:
796	if (err < 0)
797		debugfs_remove_recursive(root);
798
799	return err;
800}