xref: /freebsd/sys/compat/linuxkpi/common/src/linux_firmware.c (revision 77013d11e6483b970af25e13c9b892075742f7e5)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020-2021 The FreeBSD Foundation
5  *
6  * This software was developed by Björn Zeeb under sponsorship from
7  * the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/types.h>
36 #include <sys/malloc.h>
37 #include <sys/firmware.h>
38 #include <sys/queue.h>
39 #include <sys/taskqueue.h>
40 
41 #include <linux/types.h>
42 #include <linux/device.h>
43 
44 #include <linux/firmware.h>
45 #undef firmware
46 
47 MALLOC_DEFINE(M_LKPI_FW, "lkpifw", "LinuxKPI firmware");
48 
49 struct lkpi_fw_task {
50 	/* Task and arguments for the "nowait" callback. */
51 	struct task		fw_task;
52 	gfp_t			gfp;
53 	const char		*fw_name;
54 	struct device		*dev;
55 	void			*drv;
56 	void(*cont)(const struct linuxkpi_firmware *, void *);
57 };
58 
59 static int
60 _linuxkpi_request_firmware(const char *fw_name, const struct linuxkpi_firmware **fw,
61     struct device *dev, gfp_t gfp __unused, bool enoentok, bool warn)
62 {
63 	const struct firmware *fbdfw;
64 	struct linuxkpi_firmware *lfw;
65 	const char *fwimg;
66 	char *p;
67 	uint32_t flags;
68 
69 	if (fw_name == NULL || fw == NULL || dev == NULL) {
70 		*fw = NULL;
71 		return (-EINVAL);
72 	}
73 
74 	/* Set independent on "warn". To debug, bootverbose is avail. */
75 	flags = FIRMWARE_GET_NOWARN;
76 
77 	KASSERT(gfp == GFP_KERNEL, ("%s: gfp %#x\n", __func__, gfp));
78 	lfw = malloc(sizeof(*lfw), M_LKPI_FW, M_WAITOK | M_ZERO);
79 
80 	/*
81 	 * Linux can have a path in the firmware which is hard to replicate
82 	 * for auto-firmware-module-loading.
83 	 * On FreeBSD, depending on what people do, the firmware will either
84 	 * be called "fw", or "dir_fw", or "modname_dir_fw".  The latter the
85 	 * driver author has to deal with herself (requesting the special name).
86 	 * We also optionally flatten '/'s and '.'s as some firmware modules do.
87 	 * We probe in the least-of-work order avoiding memory operations.
88 	 * It will be preferred to build the firmware .ko in a well matching
89 	 * way rather than adding more name-mangling-hacks here in the future
90 	 * (though we could if needed).
91 	 */
92 	/* (1) Try any name removed of path. */
93 	fwimg = strrchr(fw_name, '/');
94 	if (fwimg != NULL)
95 		fwimg++;
96 	if (fwimg == NULL || *fwimg == '\0')
97 		fwimg = fw_name;
98 	fbdfw = firmware_get_flags(fwimg, flags);
99 	/* (2) Try the original name if we have not yet. */
100 	if (fbdfw == NULL && fwimg != fw_name) {
101 		fwimg = fw_name;
102 		fbdfw = firmware_get_flags(fwimg, flags);
103 	}
104 	/* (3) Flatten '/', '.' and '-' to '_' and try with adjusted name. */
105 	if (fbdfw == NULL &&
106 	    (strchr(fw_name, '/') != NULL || strchr(fw_name, '.') != NULL ||
107 	    strchr(fw_name, '-'))) {
108 		fwimg = strdup(fw_name, M_LKPI_FW);
109 		if (fwimg != NULL) {
110 			while ((p = strchr(fwimg, '/')) != NULL)
111 				*p = '_';
112 			fbdfw = firmware_get_flags(fwimg, flags);
113 			if (fbdfw == NULL) {
114 				while ((p = strchr(fwimg, '.')) != NULL)
115 					*p = '_';
116 				fbdfw = firmware_get_flags(fwimg, flags);
117 			}
118 			if (fbdfw == NULL) {
119 				while ((p = strchr(fwimg, '-')) != NULL)
120 					*p = '_';
121 				fbdfw = firmware_get_flags(fwimg, flags);
122 			}
123 			free(__DECONST(void *, fwimg), M_LKPI_FW);
124 		}
125 	}
126 	if (fbdfw == NULL) {
127 		if (enoentok)
128 			*fw = lfw;
129 		else {
130 			free(lfw, M_LKPI_FW);
131 			*fw = NULL;
132 		}
133 		if (warn)
134 			device_printf(dev->bsddev, "could not load firmware "
135 			    "image '%s'\n", fw_name);
136 		return (-ENOENT);
137 	}
138 
139 	device_printf(dev->bsddev,"successfully loaded firmware image '%s'\n",
140 	    fw_name);
141 	lfw->fbdfw = fbdfw;
142 	lfw->data = (const uint8_t *)fbdfw->data;
143 	lfw->size = fbdfw->datasize;
144 	*fw = lfw;
145 	return (0);
146 }
147 
148 static void
149 lkpi_fw_task(void *ctx, int pending)
150 {
151 	struct lkpi_fw_task *lfwt;
152 	const struct linuxkpi_firmware *fw;
153 	int error;
154 
155 	KASSERT(ctx != NULL && pending == 1, ("%s: lfwt %p, pending %d\n",
156 	    __func__, ctx, pending));
157 
158 	lfwt = ctx;
159 	if (lfwt->cont == NULL)
160 		goto out;
161 
162 	error = _linuxkpi_request_firmware(lfwt->fw_name, &fw, lfwt->dev,
163 	    lfwt->gfp, true, true);
164 
165 	/*
166 	 * Linux seems to run the callback if it cannot find the firmware.
167 	 * We call it in all cases as it is the only feedback to the requester.
168 	 */
169 	lfwt->cont(fw, lfwt->drv);
170 	/* Do not assume fw is still valid! */
171 
172 out:
173 	free(lfwt, M_LKPI_FW);
174 }
175 
176 int
177 linuxkpi_request_firmware_nowait(struct module *mod __unused, bool _t __unused,
178     const char *fw_name, struct device *dev, gfp_t gfp, void *drv,
179     void(*cont)(const struct linuxkpi_firmware *, void *))
180 {
181 	struct lkpi_fw_task *lfwt;
182 	int error;
183 
184 	lfwt = malloc(sizeof(*lfwt), M_LKPI_FW, M_WAITOK | M_ZERO);
185 	lfwt->gfp = gfp;
186 	lfwt->fw_name = fw_name;
187 	lfwt->dev = dev;
188 	lfwt->drv = drv;
189 	lfwt->cont = cont;
190 	TASK_INIT(&lfwt->fw_task, 0, lkpi_fw_task, lfwt);
191 	error = taskqueue_enqueue(taskqueue_thread, &lfwt->fw_task);
192 
193 	if (error)
194 		return (-error);
195 	return (0);
196 }
197 
198 int
199 linuxkpi_request_firmware(const struct linuxkpi_firmware **fw,
200     const char *fw_name, struct device *dev)
201 {
202 
203 	return (_linuxkpi_request_firmware(fw_name, fw, dev, GFP_KERNEL, false,
204 	    true));
205 }
206 
207 int
208 linuxkpi_firmware_request_nowarn(const struct linuxkpi_firmware **fw,
209     const char *fw_name, struct device *dev)
210 {
211 
212 	return (_linuxkpi_request_firmware(fw_name, fw, dev, GFP_KERNEL, false,
213 	    false));
214 }
215 
216 void
217 linuxkpi_release_firmware(const struct linuxkpi_firmware *fw)
218 {
219 
220 	if (fw == NULL)
221 		return;
222 
223 	if (fw->fbdfw)
224 		firmware_put(fw->fbdfw, FIRMWARE_UNLOAD);
225 	free(__DECONST(void *, fw), M_LKPI_FW);
226 }
227