1 // SPDX-License-Identifier: GPL-2.0-only
6  * Re-worked to expose sysfs APIs by mikew@google.com (Mike Waychison)
19 #include <linux/dma-mapping.h>
40 #define GSMI_SHUTDOWN_DIE	4	/* Die -- No longer meaningful */
131  * Some platforms don't have explicit SMI handshake
138 	"The number of loop iterations to use when using the spin handshake.");
142  * avoid any side-effects of generating an SMI for S0ix logging, use the S0ix
160 	smibuf->start = dma_pool_alloc(gsmi_dev.dma_pool, GFP_KERNEL,  in gsmi_buf_alloc()
161 				       &smibuf->handle);  in gsmi_buf_alloc()
162 	if (!smibuf->start) {  in gsmi_buf_alloc()
169 	smibuf->length = GSMI_BUF_SIZE;  in gsmi_buf_alloc()
170 	smibuf->address = (u32)virt_to_phys(smibuf->start);  in gsmi_buf_alloc()
178 		if (smibuf->start)  in gsmi_buf_free()
179 			dma_pool_free(gsmi_dev.dma_pool, smibuf->start,  in gsmi_buf_free()
180 				      smibuf->handle);  in gsmi_buf_free()
187  * in-kernel errnos (0 on success, -ERRNO on error).
218 			  "b" (gsmi_dev.param_buf->address)  in gsmi_exec()
224 		 * hundred-ish usecs to ensure the SMI has triggered.  in gsmi_exec()
232 			  "b" (gsmi_dev.param_buf->address),  in gsmi_exec()
247 			  "b" (gsmi_dev.param_buf->address)  in gsmi_exec()
262 		rc = -EINVAL;  in gsmi_exec()
266 		rc = -ENOMEM;  in gsmi_exec()
273 		rc = -ENOSYS;  in gsmi_exec()
277 		rc = -EBUSY;  in gsmi_exec()
281 		rc = -EFAULT;  in gsmi_exec()
285 		rc = -ENOENT;  in gsmi_exec()
289 		rc = -ENOSPC;  in gsmi_exec()
299 		rc = -ENXIO;  in gsmi_exec()
315 		.name_ptr = gsmi_dev.name_buf->address,  in gsmi_get_variable()
316 		.data_ptr = gsmi_dev.data_buf->address,  in gsmi_get_variable()
332 	/* variable name, already in UTF-16 */  in gsmi_get_variable()
333 	memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length);  in gsmi_get_variable()
334 	memcpy(gsmi_dev.name_buf->start, name, name_len * 2);  in gsmi_get_variable()
337 	memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);  in gsmi_get_variable()
340 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_get_variable()
341 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in gsmi_get_variable()
352 		memcpy(&param, gsmi_dev.param_buf->start, sizeof(param));  in gsmi_get_variable()
356 						gsmi_dev.data_buf->length);  in gsmi_get_variable()
360 		memcpy(data, gsmi_dev.data_buf->start, *data_size);  in gsmi_get_variable()
379 		.name_ptr = gsmi_dev.name_buf->address,  in gsmi_get_next_variable()
380 		.name_len = gsmi_dev.name_buf->length,  in gsmi_get_next_variable()
390 	/* Let's make sure the thing is at least null-terminated */  in gsmi_get_next_variable()
399 	/* variable name, already in UTF-16 */  in gsmi_get_next_variable()
400 	memcpy(gsmi_dev.name_buf->start, name, *name_size);  in gsmi_get_next_variable()
403 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_get_next_variable()
404 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in gsmi_get_next_variable()
411 		/* variable not found -- end of list */  in gsmi_get_next_variable()
415 		memcpy(&param, gsmi_dev.param_buf->start, sizeof(param));  in gsmi_get_next_variable()
418 		memcpy(name, gsmi_dev.name_buf->start, GSMI_BUF_SIZE);  in gsmi_get_next_variable()
438 		.name_ptr = gsmi_dev.name_buf->address,  in gsmi_set_variable()
439 		.data_ptr = gsmi_dev.data_buf->address,  in gsmi_set_variable()
458 	/* variable name, already in UTF-16 */  in gsmi_set_variable()
459 	memset(gsmi_dev.name_buf->start, 0, gsmi_dev.name_buf->length);  in gsmi_set_variable()
460 	memcpy(gsmi_dev.name_buf->start, name, name_len * 2);  in gsmi_set_variable()
463 	memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);  in gsmi_set_variable()
464 	memcpy(gsmi_dev.data_buf->start, data, data_size);  in gsmi_set_variable()
467 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_set_variable()
468 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in gsmi_set_variable()
494 		.data_ptr = gsmi_dev.data_buf->address,  in eventlog_write()
501 		return -EINVAL;  in eventlog_write()
506 	if ((count - sizeof(u32)) > gsmi_dev.data_buf->length)  in eventlog_write()
507 		return -EINVAL;  in eventlog_write()
508 	param.data_len = count - sizeof(u32);  in eventlog_write()
513 	memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);  in eventlog_write()
514 	memcpy(gsmi_dev.data_buf->start, buf, param.data_len);  in eventlog_write()
517 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in eventlog_write()
518 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in eventlog_write()
556 		return -EINVAL;  in gsmi_clear_eventlog_store()
565 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_clear_eventlog_store()
566 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in gsmi_clear_eventlog_store()
592 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_clear_config_store()
637 	memset(gsmi_dev.data_buf->start, 0, gsmi_dev.data_buf->length);  in gsmi_shutdown_reason()
638 	memcpy(gsmi_dev.data_buf->start, &entry, sizeof(entry));  in gsmi_shutdown_reason()
641 	param.data_ptr = gsmi_dev.data_buf->address;  in gsmi_shutdown_reason()
642 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_shutdown_reason()
643 	memcpy(gsmi_dev.param_buf->start, &param, sizeof(param));  in gsmi_shutdown_reason()
708  * to identify a board and provide the appropriate quirk -- mikew@google.com
717 	hash -= n;  in local_hash_64()
719 	hash -= n;  in local_hash_64()
723 	hash -= n;  in local_hash_64()
729 	/* High bits are more random, so use them. */  in local_hash_64()
730 	return hash >> (64 - bits);  in local_hash_64()
763 		return -ENODEV;  in gsmi_system_valid()
769 	 * Newer firmware doesn't do that though, so use that as the  in gsmi_system_valid()
775 		return -ENODEV;  in gsmi_system_valid()
785 			return -ENODEV;  in gsmi_system_valid()
792 		return -ENODEV;  in gsmi_system_valid()
809 		return -ENODEV;  in gsmi_system_valid()
820 	.id		= -1,
839 	memset(gsmi_dev.param_buf->start, 0, gsmi_dev.param_buf->length);  in gsmi_log_s0ix_info()
926 	ret = -ENOMEM;  in gsmi_init()
927 	gsmi_dev.dma_pool = dma_pool_create("gsmi", &gsmi_dev.pdev->dev,  in gsmi_init()
933 	 * pre-allocate buffers because sometimes we are called when  in gsmi_init()
955 	 * Determine type of handshake used to serialize the SMI  in gsmi_init()
962 	 * behavior, implement a handshake between the kernel driver and the  in gsmi_init()
964 	 * the type of handshake.  in gsmi_init()
967 	 * handshake. Either it doesn't need to, or it's legacy firmware  in gsmi_init()
974 	 * SPIN: The firmware handler does not implement any handshake  in gsmi_init()
978 	 * Finally, the handler will return -ENOSYS if  in gsmi_init()
986 	if (gsmi_dev.handshake_type == -ENOSYS)  in gsmi_init()
990 	/* Remove and clean up gsmi if the handshake could not complete. */  in gsmi_init()
991 	if (gsmi_dev.handshake_type == -ENXIO) {  in gsmi_init()
994 		ret = -ENODEV;  in gsmi_init()
999 	ret = -ENOMEM;  in gsmi_init()