1 /* Copyright 2013-2014 Freescale Semiconductor Inc.
2  *
3  * I/O services to send MC commands to the MC hardware
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of the above-listed copyright holders nor the
13  *       names of any contributors may be used to endorse or promote products
14  *       derived from this software without specific prior written permission.
15  *
16  *
17  * ALTERNATIVELY, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") as published by the Free Software
19  * Foundation, either version 2 of that License or (at your option) any
20  * later version.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include "../include/mc-sys.h"
36 #include "../include/mc-cmd.h"
37 #include "../include/mc.h"
38 #include <linux/delay.h>
39 #include <linux/slab.h>
40 #include <linux/ioport.h>
41 #include <linux/device.h>
42 #include "dpmcp.h"
43 
44 /**
45  * Timeout in milliseconds to wait for the completion of an MC command
46  */
47 #define MC_CMD_COMPLETION_TIMEOUT_MS	500
48 
49 /*
50  * usleep_range() min and max values used to throttle down polling
51  * iterations while waiting for MC command completion
52  */
53 #define MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS    10
54 #define MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS    500
55 
56 #define MC_CMD_HDR_READ_CMDID(_hdr) \
57 	((u16)mc_dec((_hdr), MC_CMD_HDR_CMDID_O, MC_CMD_HDR_CMDID_S))
58 
59 /**
60  * Creates an MC I/O object
61  *
62  * @dev: device to be associated with the MC I/O object
63  * @mc_portal_phys_addr: physical address of the MC portal to use
64  * @mc_portal_size: size in bytes of the MC portal
65  * @dpmcp-dev: Pointer to the DPMCP object associated with this MC I/O
66  * object or NULL if none.
67  * @flags: flags for the new MC I/O object
68  * @new_mc_io: Area to return pointer to newly created MC I/O object
69  *
70  * Returns '0' on Success; Error code otherwise.
71  */
fsl_create_mc_io(struct device * dev,phys_addr_t mc_portal_phys_addr,u32 mc_portal_size,struct fsl_mc_device * dpmcp_dev,u32 flags,struct fsl_mc_io ** new_mc_io)72 int __must_check fsl_create_mc_io(struct device *dev,
73 				  phys_addr_t mc_portal_phys_addr,
74 				  u32 mc_portal_size,
75 				  struct fsl_mc_device *dpmcp_dev,
76 				  u32 flags, struct fsl_mc_io **new_mc_io)
77 {
78 	int error;
79 	struct fsl_mc_io *mc_io;
80 	void __iomem *mc_portal_virt_addr;
81 	struct resource *res;
82 
83 	mc_io = devm_kzalloc(dev, sizeof(*mc_io), GFP_KERNEL);
84 	if (!mc_io)
85 		return -ENOMEM;
86 
87 	mc_io->dev = dev;
88 	mc_io->flags = flags;
89 	mc_io->portal_phys_addr = mc_portal_phys_addr;
90 	mc_io->portal_size = mc_portal_size;
91 	if (flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
92 		spin_lock_init(&mc_io->spinlock);
93 	else
94 		mutex_init(&mc_io->mutex);
95 
96 	res = devm_request_mem_region(dev,
97 				      mc_portal_phys_addr,
98 				      mc_portal_size,
99 				      "mc_portal");
100 	if (!res) {
101 		dev_err(dev,
102 			"devm_request_mem_region failed for MC portal %#llx\n",
103 			mc_portal_phys_addr);
104 		return -EBUSY;
105 	}
106 
107 	mc_portal_virt_addr = devm_ioremap_nocache(dev,
108 						   mc_portal_phys_addr,
109 						   mc_portal_size);
110 	if (!mc_portal_virt_addr) {
111 		dev_err(dev,
112 			"devm_ioremap_nocache failed for MC portal %#llx\n",
113 			mc_portal_phys_addr);
114 		return -ENXIO;
115 	}
116 
117 	mc_io->portal_virt_addr = mc_portal_virt_addr;
118 	if (dpmcp_dev) {
119 		error = fsl_mc_io_set_dpmcp(mc_io, dpmcp_dev);
120 		if (error < 0)
121 			goto error_destroy_mc_io;
122 	}
123 
124 	*new_mc_io = mc_io;
125 	return 0;
126 
127 error_destroy_mc_io:
128 	fsl_destroy_mc_io(mc_io);
129 	return error;
130 }
131 EXPORT_SYMBOL_GPL(fsl_create_mc_io);
132 
133 /**
134  * Destroys an MC I/O object
135  *
136  * @mc_io: MC I/O object to destroy
137  */
fsl_destroy_mc_io(struct fsl_mc_io * mc_io)138 void fsl_destroy_mc_io(struct fsl_mc_io *mc_io)
139 {
140 	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
141 
142 	if (dpmcp_dev)
143 		fsl_mc_io_unset_dpmcp(mc_io);
144 
145 	devm_iounmap(mc_io->dev, mc_io->portal_virt_addr);
146 	devm_release_mem_region(mc_io->dev,
147 				mc_io->portal_phys_addr,
148 				mc_io->portal_size);
149 
150 	mc_io->portal_virt_addr = NULL;
151 	devm_kfree(mc_io->dev, mc_io);
152 }
153 EXPORT_SYMBOL_GPL(fsl_destroy_mc_io);
154 
fsl_mc_io_set_dpmcp(struct fsl_mc_io * mc_io,struct fsl_mc_device * dpmcp_dev)155 int fsl_mc_io_set_dpmcp(struct fsl_mc_io *mc_io,
156 			struct fsl_mc_device *dpmcp_dev)
157 {
158 	int error;
159 
160 	if (WARN_ON(!dpmcp_dev))
161 		return -EINVAL;
162 
163 	if (WARN_ON(mc_io->dpmcp_dev))
164 		return -EINVAL;
165 
166 	if (WARN_ON(dpmcp_dev->mc_io))
167 		return -EINVAL;
168 
169 	error = dpmcp_open(mc_io,
170 			   0,
171 			   dpmcp_dev->obj_desc.id,
172 			   &dpmcp_dev->mc_handle);
173 	if (error < 0)
174 		return error;
175 
176 	mc_io->dpmcp_dev = dpmcp_dev;
177 	dpmcp_dev->mc_io = mc_io;
178 	return 0;
179 }
180 EXPORT_SYMBOL_GPL(fsl_mc_io_set_dpmcp);
181 
fsl_mc_io_unset_dpmcp(struct fsl_mc_io * mc_io)182 void fsl_mc_io_unset_dpmcp(struct fsl_mc_io *mc_io)
183 {
184 	int error;
185 	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
186 
187 	if (WARN_ON(!dpmcp_dev))
188 		return;
189 
190 	if (WARN_ON(dpmcp_dev->mc_io != mc_io))
191 		return;
192 
193 	error = dpmcp_close(mc_io,
194 			    0,
195 			    dpmcp_dev->mc_handle);
196 	if (error < 0) {
197 		dev_err(&dpmcp_dev->dev, "dpmcp_close() failed: %d\n",
198 			error);
199 	}
200 
201 	mc_io->dpmcp_dev = NULL;
202 	dpmcp_dev->mc_io = NULL;
203 }
204 EXPORT_SYMBOL_GPL(fsl_mc_io_unset_dpmcp);
205 
mc_status_to_error(enum mc_cmd_status status)206 static int mc_status_to_error(enum mc_cmd_status status)
207 {
208 	static const int mc_status_to_error_map[] = {
209 		[MC_CMD_STATUS_OK] = 0,
210 		[MC_CMD_STATUS_AUTH_ERR] = -EACCES,
211 		[MC_CMD_STATUS_NO_PRIVILEGE] = -EPERM,
212 		[MC_CMD_STATUS_DMA_ERR] = -EIO,
213 		[MC_CMD_STATUS_CONFIG_ERR] = -ENXIO,
214 		[MC_CMD_STATUS_TIMEOUT] = -ETIMEDOUT,
215 		[MC_CMD_STATUS_NO_RESOURCE] = -ENAVAIL,
216 		[MC_CMD_STATUS_NO_MEMORY] = -ENOMEM,
217 		[MC_CMD_STATUS_BUSY] = -EBUSY,
218 		[MC_CMD_STATUS_UNSUPPORTED_OP] = -ENOTSUPP,
219 		[MC_CMD_STATUS_INVALID_STATE] = -ENODEV,
220 	};
221 
222 	if (WARN_ON((u32)status >= ARRAY_SIZE(mc_status_to_error_map)))
223 		return -EINVAL;
224 
225 	return mc_status_to_error_map[status];
226 }
227 
mc_status_to_string(enum mc_cmd_status status)228 static const char *mc_status_to_string(enum mc_cmd_status status)
229 {
230 	static const char *const status_strings[] = {
231 		[MC_CMD_STATUS_OK] = "Command completed successfully",
232 		[MC_CMD_STATUS_READY] = "Command ready to be processed",
233 		[MC_CMD_STATUS_AUTH_ERR] = "Authentication error",
234 		[MC_CMD_STATUS_NO_PRIVILEGE] = "No privilege",
235 		[MC_CMD_STATUS_DMA_ERR] = "DMA or I/O error",
236 		[MC_CMD_STATUS_CONFIG_ERR] = "Configuration error",
237 		[MC_CMD_STATUS_TIMEOUT] = "Operation timed out",
238 		[MC_CMD_STATUS_NO_RESOURCE] = "No resources",
239 		[MC_CMD_STATUS_NO_MEMORY] = "No memory available",
240 		[MC_CMD_STATUS_BUSY] = "Device is busy",
241 		[MC_CMD_STATUS_UNSUPPORTED_OP] = "Unsupported operation",
242 		[MC_CMD_STATUS_INVALID_STATE] = "Invalid state"
243 	};
244 
245 	if ((unsigned int)status >= ARRAY_SIZE(status_strings))
246 		return "Unknown MC error";
247 
248 	return status_strings[status];
249 }
250 
251 /**
252  * mc_write_command - writes a command to a Management Complex (MC) portal
253  *
254  * @portal: pointer to an MC portal
255  * @cmd: pointer to a filled command
256  */
mc_write_command(struct mc_command __iomem * portal,struct mc_command * cmd)257 static inline void mc_write_command(struct mc_command __iomem *portal,
258 				    struct mc_command *cmd)
259 {
260 	int i;
261 
262 	/* copy command parameters into the portal */
263 	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
264 		writeq(cmd->params[i], &portal->params[i]);
265 
266 	/* submit the command by writing the header */
267 	writeq(cmd->header, &portal->header);
268 }
269 
270 /**
271  * mc_read_response - reads the response for the last MC command from a
272  * Management Complex (MC) portal
273  *
274  * @portal: pointer to an MC portal
275  * @resp: pointer to command response buffer
276  *
277  * Returns MC_CMD_STATUS_OK on Success; Error code otherwise.
278  */
mc_read_response(struct mc_command __iomem * portal,struct mc_command * resp)279 static inline enum mc_cmd_status mc_read_response(struct mc_command __iomem *
280 						  portal,
281 						  struct mc_command *resp)
282 {
283 	int i;
284 	enum mc_cmd_status status;
285 
286 	/* Copy command response header from MC portal: */
287 	resp->header = readq(&portal->header);
288 	status = MC_CMD_HDR_READ_STATUS(resp->header);
289 	if (status != MC_CMD_STATUS_OK)
290 		return status;
291 
292 	/* Copy command response data from MC portal: */
293 	for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++)
294 		resp->params[i] = readq(&portal->params[i]);
295 
296 	return status;
297 }
298 
299 /**
300  * Waits for the completion of an MC command doing preemptible polling.
301  * uslepp_range() is called between polling iterations.
302  *
303  * @mc_io: MC I/O object to be used
304  * @cmd: command buffer to receive MC response
305  * @mc_status: MC command completion status
306  */
mc_polling_wait_preemptible(struct fsl_mc_io * mc_io,struct mc_command * cmd,enum mc_cmd_status * mc_status)307 static int mc_polling_wait_preemptible(struct fsl_mc_io *mc_io,
308 				       struct mc_command *cmd,
309 				       enum mc_cmd_status *mc_status)
310 {
311 	enum mc_cmd_status status;
312 	unsigned long jiffies_until_timeout =
313 		jiffies + msecs_to_jiffies(MC_CMD_COMPLETION_TIMEOUT_MS);
314 
315 	/*
316 	 * Wait for response from the MC hardware:
317 	 */
318 	for (;;) {
319 		status = mc_read_response(mc_io->portal_virt_addr, cmd);
320 		if (status != MC_CMD_STATUS_READY)
321 			break;
322 
323 		/*
324 		 * TODO: When MC command completion interrupts are supported
325 		 * call wait function here instead of usleep_range()
326 		 */
327 		usleep_range(MC_CMD_COMPLETION_POLLING_MIN_SLEEP_USECS,
328 			     MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
329 
330 		if (time_after_eq(jiffies, jiffies_until_timeout)) {
331 			pr_debug("MC command timed out (portal: %#llx, obj handle: %#x, command: %#x)\n",
332 				 mc_io->portal_phys_addr,
333 				 (unsigned int)
334 					MC_CMD_HDR_READ_TOKEN(cmd->header),
335 				 (unsigned int)
336 					MC_CMD_HDR_READ_CMDID(cmd->header));
337 
338 			return -ETIMEDOUT;
339 		}
340 	}
341 
342 	*mc_status = status;
343 	return 0;
344 }
345 
346 /**
347  * Waits for the completion of an MC command doing atomic polling.
348  * udelay() is called between polling iterations.
349  *
350  * @mc_io: MC I/O object to be used
351  * @cmd: command buffer to receive MC response
352  * @mc_status: MC command completion status
353  */
mc_polling_wait_atomic(struct fsl_mc_io * mc_io,struct mc_command * cmd,enum mc_cmd_status * mc_status)354 static int mc_polling_wait_atomic(struct fsl_mc_io *mc_io,
355 				  struct mc_command *cmd,
356 				  enum mc_cmd_status *mc_status)
357 {
358 	enum mc_cmd_status status;
359 	unsigned long timeout_usecs = MC_CMD_COMPLETION_TIMEOUT_MS * 1000;
360 
361 	BUILD_BUG_ON((MC_CMD_COMPLETION_TIMEOUT_MS * 1000) %
362 		     MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS != 0);
363 
364 	for (;;) {
365 		status = mc_read_response(mc_io->portal_virt_addr, cmd);
366 		if (status != MC_CMD_STATUS_READY)
367 			break;
368 
369 		udelay(MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS);
370 		timeout_usecs -= MC_CMD_COMPLETION_POLLING_MAX_SLEEP_USECS;
371 		if (timeout_usecs == 0) {
372 			pr_debug("MC command timed out (portal: %#llx, obj handle: %#x, command: %#x)\n",
373 				 mc_io->portal_phys_addr,
374 				 (unsigned int)
375 					MC_CMD_HDR_READ_TOKEN(cmd->header),
376 				 (unsigned int)
377 					MC_CMD_HDR_READ_CMDID(cmd->header));
378 
379 			return -ETIMEDOUT;
380 		}
381 	}
382 
383 	*mc_status = status;
384 	return 0;
385 }
386 
387 /**
388  * Sends a command to the MC device using the given MC I/O object
389  *
390  * @mc_io: MC I/O object to be used
391  * @cmd: command to be sent
392  *
393  * Returns '0' on Success; Error code otherwise.
394  */
mc_send_command(struct fsl_mc_io * mc_io,struct mc_command * cmd)395 int mc_send_command(struct fsl_mc_io *mc_io, struct mc_command *cmd)
396 {
397 	int error;
398 	enum mc_cmd_status status;
399 	unsigned long irq_flags = 0;
400 
401 	if (WARN_ON(in_irq() &&
402 		    !(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)))
403 		return -EINVAL;
404 
405 	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
406 		spin_lock_irqsave(&mc_io->spinlock, irq_flags);
407 	else
408 		mutex_lock(&mc_io->mutex);
409 
410 	/*
411 	 * Send command to the MC hardware:
412 	 */
413 	mc_write_command(mc_io->portal_virt_addr, cmd);
414 
415 	/*
416 	 * Wait for response from the MC hardware:
417 	 */
418 	if (!(mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL))
419 		error = mc_polling_wait_preemptible(mc_io, cmd, &status);
420 	else
421 		error = mc_polling_wait_atomic(mc_io, cmd, &status);
422 
423 	if (error < 0)
424 		goto common_exit;
425 
426 	if (status != MC_CMD_STATUS_OK) {
427 		pr_debug("MC command failed: portal: %#llx, obj handle: %#x, command: %#x, status: %s (%#x)\n",
428 			 mc_io->portal_phys_addr,
429 			 (unsigned int)MC_CMD_HDR_READ_TOKEN(cmd->header),
430 			 (unsigned int)MC_CMD_HDR_READ_CMDID(cmd->header),
431 			 mc_status_to_string(status),
432 			 (unsigned int)status);
433 
434 		error = mc_status_to_error(status);
435 		goto common_exit;
436 	}
437 
438 	error = 0;
439 common_exit:
440 	if (mc_io->flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
441 		spin_unlock_irqrestore(&mc_io->spinlock, irq_flags);
442 	else
443 		mutex_unlock(&mc_io->mutex);
444 
445 	return error;
446 }
447 EXPORT_SYMBOL(mc_send_command);
448