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1// SPDX-License-Identifier: GPL-2.02/*3 * Management-Controller-to-Driver Interface4 *5 * Copyright 2008-2013 Solarflare Communications Inc.6 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.7 */8#include <linux/delay.h>9#include <linux/slab.h>10#include <linux/io.h>11#include <linux/spinlock.h>12#include <linux/netdevice.h>13#include <linux/etherdevice.h>14#include <linux/ethtool.h>15#include <linux/if_vlan.h>16#include <linux/timer.h>17#include <linux/list.h>18#include <linux/pci.h>19#include <linux/device.h>20#include <linux/rwsem.h>21#include <linux/vmalloc.h>22#include <net/netevent.h>23#include <linux/log2.h>24#include <linux/net_tstamp.h>25#include <linux/wait.h>26 27#include "bitfield.h"28#include "mcdi.h"29 30static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd);31static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx);32static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,33				       struct cdx_mcdi_cmd *cmd,34				       unsigned int *handle);35static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,36				    bool allow_retry);37static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,38					struct cdx_mcdi_cmd *cmd);39static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,40				  struct cdx_mcdi_cmd *cmd,41				  struct cdx_dword *outbuf,42				  int len,43				  struct list_head *cleanup_list);44static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,45				 struct cdx_mcdi_cmd *cmd,46				 struct list_head *cleanup_list);47static void cdx_mcdi_cmd_work(struct work_struct *context);48static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list);49static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,50				    size_t inlen, int raw, int arg, int err_no);51 52static bool cdx_cmd_cancelled(struct cdx_mcdi_cmd *cmd)53{54	return cmd->state == MCDI_STATE_RUNNING_CANCELLED;55}56 57static void cdx_mcdi_cmd_release(struct kref *ref)58{59	kfree(container_of(ref, struct cdx_mcdi_cmd, ref));60}61 62static unsigned int cdx_mcdi_cmd_handle(struct cdx_mcdi_cmd *cmd)63{64	return cmd->handle;65}66 67static void _cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,68				 struct cdx_mcdi_cmd *cmd,69				 struct list_head *cleanup_list)70{71	/* if cancelled, the completers have already been called */72	if (cdx_cmd_cancelled(cmd))73		return;74 75	if (cmd->completer) {76		list_add_tail(&cmd->cleanup_list, cleanup_list);77		++mcdi->outstanding_cleanups;78		kref_get(&cmd->ref);79	}80}81 82static void cdx_mcdi_remove_cmd(struct cdx_mcdi_iface *mcdi,83				struct cdx_mcdi_cmd *cmd,84				struct list_head *cleanup_list)85{86	list_del(&cmd->list);87	_cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);88	cmd->state = MCDI_STATE_FINISHED;89	kref_put(&cmd->ref, cdx_mcdi_cmd_release);90	if (list_empty(&mcdi->cmd_list))91		wake_up(&mcdi->cmd_complete_wq);92}93 94static unsigned long cdx_mcdi_rpc_timeout(struct cdx_mcdi *cdx, unsigned int cmd)95{96	if (!cdx->mcdi_ops->mcdi_rpc_timeout)97		return MCDI_RPC_TIMEOUT;98	else99		return cdx->mcdi_ops->mcdi_rpc_timeout(cdx, cmd);100}101 102int cdx_mcdi_init(struct cdx_mcdi *cdx)103{104	struct cdx_mcdi_iface *mcdi;105	int rc = -ENOMEM;106 107	cdx->mcdi = kzalloc(sizeof(*cdx->mcdi), GFP_KERNEL);108	if (!cdx->mcdi)109		goto fail;110 111	mcdi = cdx_mcdi_if(cdx);112	mcdi->cdx = cdx;113 114	mcdi->workqueue = alloc_ordered_workqueue("mcdi_wq", 0);115	if (!mcdi->workqueue)116		goto fail2;117	mutex_init(&mcdi->iface_lock);118	mcdi->mode = MCDI_MODE_EVENTS;119	INIT_LIST_HEAD(&mcdi->cmd_list);120	init_waitqueue_head(&mcdi->cmd_complete_wq);121 122	mcdi->new_epoch = true;123 124	return 0;125fail2:126	kfree(cdx->mcdi);127	cdx->mcdi = NULL;128fail:129	return rc;130}131 132void cdx_mcdi_finish(struct cdx_mcdi *cdx)133{134	struct cdx_mcdi_iface *mcdi;135 136	mcdi = cdx_mcdi_if(cdx);137	if (!mcdi)138		return;139 140	cdx_mcdi_wait_for_cleanup(cdx);141 142	destroy_workqueue(mcdi->workqueue);143	kfree(cdx->mcdi);144	cdx->mcdi = NULL;145}146 147static bool cdx_mcdi_flushed(struct cdx_mcdi_iface *mcdi, bool ignore_cleanups)148{149	bool flushed;150 151	mutex_lock(&mcdi->iface_lock);152	flushed = list_empty(&mcdi->cmd_list) &&153		  (ignore_cleanups || !mcdi->outstanding_cleanups);154	mutex_unlock(&mcdi->iface_lock);155	return flushed;156}157 158/* Wait for outstanding MCDI commands to complete. */159static void cdx_mcdi_wait_for_cleanup(struct cdx_mcdi *cdx)160{161	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);162 163	if (!mcdi)164		return;165 166	wait_event(mcdi->cmd_complete_wq,167		   cdx_mcdi_flushed(mcdi, false));168}169 170int cdx_mcdi_wait_for_quiescence(struct cdx_mcdi *cdx,171				 unsigned int timeout_jiffies)172{173	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);174	DEFINE_WAIT_FUNC(wait, woken_wake_function);175	int rc = 0;176 177	if (!mcdi)178		return -EINVAL;179 180	flush_workqueue(mcdi->workqueue);181 182	add_wait_queue(&mcdi->cmd_complete_wq, &wait);183 184	while (!cdx_mcdi_flushed(mcdi, true)) {185		rc = wait_woken(&wait, TASK_IDLE, timeout_jiffies);186		if (rc)187			continue;188		break;189	}190 191	remove_wait_queue(&mcdi->cmd_complete_wq, &wait);192 193	if (rc > 0)194		rc = 0;195	else if (rc == 0)196		rc = -ETIMEDOUT;197 198	return rc;199}200 201static u8 cdx_mcdi_payload_csum(const struct cdx_dword *hdr, size_t hdr_len,202				const struct cdx_dword *sdu, size_t sdu_len)203{204	u8 *p = (u8 *)hdr;205	u8 csum = 0;206	int i;207 208	for (i = 0; i < hdr_len; i++)209		csum += p[i];210 211	p = (u8 *)sdu;212	for (i = 0; i < sdu_len; i++)213		csum += p[i];214 215	return ~csum & 0xff;216}217 218static void cdx_mcdi_send_request(struct cdx_mcdi *cdx,219				  struct cdx_mcdi_cmd *cmd)220{221	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);222	const struct cdx_dword *inbuf = cmd->inbuf;223	size_t inlen = cmd->inlen;224	struct cdx_dword hdr[2];225	size_t hdr_len;226	bool not_epoch;227	u32 xflags;228 229	if (!mcdi)230		return;231 232	mcdi->prev_seq = cmd->seq;233	mcdi->seq_held_by[cmd->seq] = cmd;234	mcdi->db_held_by = cmd;235	cmd->started = jiffies;236 237	not_epoch = !mcdi->new_epoch;238	xflags = 0;239 240	/* MCDI v2 */241	WARN_ON(inlen > MCDI_CTL_SDU_LEN_MAX_V2);242	CDX_POPULATE_DWORD_7(hdr[0],243			     MCDI_HEADER_RESPONSE, 0,244			     MCDI_HEADER_RESYNC, 1,245			     MCDI_HEADER_CODE, MC_CMD_V2_EXTN,246			     MCDI_HEADER_DATALEN, 0,247			     MCDI_HEADER_SEQ, cmd->seq,248			     MCDI_HEADER_XFLAGS, xflags,249			     MCDI_HEADER_NOT_EPOCH, not_epoch);250	CDX_POPULATE_DWORD_3(hdr[1],251			     MC_CMD_V2_EXTN_IN_EXTENDED_CMD, cmd->cmd,252			     MC_CMD_V2_EXTN_IN_ACTUAL_LEN, inlen,253			     MC_CMD_V2_EXTN_IN_MESSAGE_TYPE,254			     MC_CMD_V2_EXTN_IN_MCDI_MESSAGE_TYPE_PLATFORM);255	hdr_len = 8;256 257	hdr[0].cdx_u32 |= (__force __le32)(cdx_mcdi_payload_csum(hdr, hdr_len, inbuf, inlen) <<258			 MCDI_HEADER_XFLAGS_LBN);259 260	print_hex_dump_debug("MCDI REQ HEADER: ", DUMP_PREFIX_NONE, 32, 4, hdr, hdr_len, false);261	print_hex_dump_debug("MCDI REQ PAYLOAD: ", DUMP_PREFIX_NONE, 32, 4, inbuf, inlen, false);262 263	cdx->mcdi_ops->mcdi_request(cdx, hdr, hdr_len, inbuf, inlen);264 265	mcdi->new_epoch = false;266}267 268static int cdx_mcdi_errno(struct cdx_mcdi *cdx, unsigned int mcdi_err)269{270	switch (mcdi_err) {271	case 0:272	case MC_CMD_ERR_QUEUE_FULL:273		return mcdi_err;274	case MC_CMD_ERR_EPERM:275		return -EPERM;276	case MC_CMD_ERR_ENOENT:277		return -ENOENT;278	case MC_CMD_ERR_EINTR:279		return -EINTR;280	case MC_CMD_ERR_EAGAIN:281		return -EAGAIN;282	case MC_CMD_ERR_EACCES:283		return -EACCES;284	case MC_CMD_ERR_EBUSY:285		return -EBUSY;286	case MC_CMD_ERR_EINVAL:287		return -EINVAL;288	case MC_CMD_ERR_ERANGE:289		return -ERANGE;290	case MC_CMD_ERR_EDEADLK:291		return -EDEADLK;292	case MC_CMD_ERR_ENOSYS:293		return -EOPNOTSUPP;294	case MC_CMD_ERR_ETIME:295		return -ETIME;296	case MC_CMD_ERR_EALREADY:297		return -EALREADY;298	case MC_CMD_ERR_ENOSPC:299		return -ENOSPC;300	case MC_CMD_ERR_ENOMEM:301		return -ENOMEM;302	case MC_CMD_ERR_ENOTSUP:303		return -EOPNOTSUPP;304	case MC_CMD_ERR_ALLOC_FAIL:305		return -ENOBUFS;306	case MC_CMD_ERR_MAC_EXIST:307		return -EADDRINUSE;308	case MC_CMD_ERR_NO_EVB_PORT:309		return -EAGAIN;310	default:311		return -EPROTO;312	}313}314 315static void cdx_mcdi_process_cleanup_list(struct cdx_mcdi *cdx,316					  struct list_head *cleanup_list)317{318	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);319	unsigned int cleanups = 0;320 321	if (!mcdi)322		return;323 324	while (!list_empty(cleanup_list)) {325		struct cdx_mcdi_cmd *cmd =326			list_first_entry(cleanup_list,327					 struct cdx_mcdi_cmd, cleanup_list);328		cmd->completer(cdx, cmd->cookie, cmd->rc,329			       cmd->outbuf, cmd->outlen);330		list_del(&cmd->cleanup_list);331		kref_put(&cmd->ref, cdx_mcdi_cmd_release);332		++cleanups;333	}334 335	if (cleanups) {336		bool all_done;337 338		mutex_lock(&mcdi->iface_lock);339		CDX_WARN_ON_PARANOID(cleanups > mcdi->outstanding_cleanups);340		all_done = (mcdi->outstanding_cleanups -= cleanups) == 0;341		mutex_unlock(&mcdi->iface_lock);342		if (all_done)343			wake_up(&mcdi->cmd_complete_wq);344	}345}346 347static void _cdx_mcdi_cancel_cmd(struct cdx_mcdi_iface *mcdi,348				 unsigned int handle,349				 struct list_head *cleanup_list)350{351	struct cdx_mcdi_cmd *cmd;352 353	list_for_each_entry(cmd, &mcdi->cmd_list, list)354		if (cdx_mcdi_cmd_handle(cmd) == handle) {355			switch (cmd->state) {356			case MCDI_STATE_QUEUED:357			case MCDI_STATE_RETRY:358				pr_debug("command %#x inlen %zu cancelled in queue\n",359					 cmd->cmd, cmd->inlen);360				/* if not yet running, properly cancel it */361				cmd->rc = -EPIPE;362				cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);363				break;364			case MCDI_STATE_RUNNING:365			case MCDI_STATE_RUNNING_CANCELLED:366			case MCDI_STATE_FINISHED:367			default:368				/* invalid state? */369				WARN_ON(1);370			}371			break;372		}373}374 375static void cdx_mcdi_cancel_cmd(struct cdx_mcdi *cdx, struct cdx_mcdi_cmd *cmd)376{377	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);378	LIST_HEAD(cleanup_list);379 380	if (!mcdi)381		return;382 383	mutex_lock(&mcdi->iface_lock);384	cdx_mcdi_timeout_cmd(mcdi, cmd, &cleanup_list);385	mutex_unlock(&mcdi->iface_lock);386	cdx_mcdi_process_cleanup_list(cdx, &cleanup_list);387}388 389struct cdx_mcdi_blocking_data {390	struct kref ref;391	bool done;392	wait_queue_head_t wq;393	int rc;394	struct cdx_dword *outbuf;395	size_t outlen;396	size_t outlen_actual;397};398 399static void cdx_mcdi_blocking_data_release(struct kref *ref)400{401	kfree(container_of(ref, struct cdx_mcdi_blocking_data, ref));402}403 404static void cdx_mcdi_rpc_completer(struct cdx_mcdi *cdx, unsigned long cookie,405				   int rc, struct cdx_dword *outbuf,406				   size_t outlen_actual)407{408	struct cdx_mcdi_blocking_data *wait_data =409		(struct cdx_mcdi_blocking_data *)cookie;410 411	wait_data->rc = rc;412	memcpy(wait_data->outbuf, outbuf,413	       min(outlen_actual, wait_data->outlen));414	wait_data->outlen_actual = outlen_actual;415	/* memory barrier */416	smp_wmb();417	wait_data->done = true;418	wake_up(&wait_data->wq);419	kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);420}421 422static int cdx_mcdi_rpc_sync(struct cdx_mcdi *cdx, unsigned int cmd,423			     const struct cdx_dword *inbuf, size_t inlen,424			     struct cdx_dword *outbuf, size_t outlen,425			     size_t *outlen_actual, bool quiet)426{427	struct cdx_mcdi_blocking_data *wait_data;428	struct cdx_mcdi_cmd *cmd_item;429	unsigned int handle;430	int rc;431 432	if (outlen_actual)433		*outlen_actual = 0;434 435	wait_data = kmalloc(sizeof(*wait_data), GFP_KERNEL);436	if (!wait_data)437		return -ENOMEM;438 439	cmd_item = kmalloc(sizeof(*cmd_item), GFP_KERNEL);440	if (!cmd_item) {441		kfree(wait_data);442		return -ENOMEM;443	}444 445	kref_init(&wait_data->ref);446	wait_data->done = false;447	init_waitqueue_head(&wait_data->wq);448	wait_data->outbuf = outbuf;449	wait_data->outlen = outlen;450 451	kref_init(&cmd_item->ref);452	cmd_item->quiet = quiet;453	cmd_item->cookie = (unsigned long)wait_data;454	cmd_item->completer = &cdx_mcdi_rpc_completer;455	cmd_item->cmd = cmd;456	cmd_item->inlen = inlen;457	cmd_item->inbuf = inbuf;458 459	/* Claim an extra reference for the completer to put. */460	kref_get(&wait_data->ref);461	rc = cdx_mcdi_rpc_async_internal(cdx, cmd_item, &handle);462	if (rc) {463		kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);464		goto out;465	}466 467	if (!wait_event_timeout(wait_data->wq, wait_data->done,468				cdx_mcdi_rpc_timeout(cdx, cmd)) &&469	    !wait_data->done) {470		pr_err("MC command 0x%x inlen %zu timed out (sync)\n",471		       cmd, inlen);472 473		cdx_mcdi_cancel_cmd(cdx, cmd_item);474 475		wait_data->rc = -ETIMEDOUT;476		wait_data->outlen_actual = 0;477	}478 479	if (outlen_actual)480		*outlen_actual = wait_data->outlen_actual;481	rc = wait_data->rc;482 483out:484	kref_put(&wait_data->ref, cdx_mcdi_blocking_data_release);485 486	return rc;487}488 489static bool cdx_mcdi_get_seq(struct cdx_mcdi_iface *mcdi, unsigned char *seq)490{491	*seq = mcdi->prev_seq;492	do {493		*seq = (*seq + 1) % ARRAY_SIZE(mcdi->seq_held_by);494	} while (mcdi->seq_held_by[*seq] && *seq != mcdi->prev_seq);495	return !mcdi->seq_held_by[*seq];496}497 498static int cdx_mcdi_rpc_async_internal(struct cdx_mcdi *cdx,499				       struct cdx_mcdi_cmd *cmd,500				       unsigned int *handle)501{502	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);503	LIST_HEAD(cleanup_list);504 505	if (!mcdi) {506		kref_put(&cmd->ref, cdx_mcdi_cmd_release);507		return -ENETDOWN;508	}509 510	if (mcdi->mode == MCDI_MODE_FAIL) {511		kref_put(&cmd->ref, cdx_mcdi_cmd_release);512		return -ENETDOWN;513	}514 515	cmd->mcdi = mcdi;516	INIT_WORK(&cmd->work, cdx_mcdi_cmd_work);517	INIT_LIST_HEAD(&cmd->list);518	INIT_LIST_HEAD(&cmd->cleanup_list);519	cmd->rc = 0;520	cmd->outbuf = NULL;521	cmd->outlen = 0;522 523	queue_work(mcdi->workqueue, &cmd->work);524	return 0;525}526 527static void cdx_mcdi_cmd_start_or_queue(struct cdx_mcdi_iface *mcdi,528					struct cdx_mcdi_cmd *cmd)529{530	struct cdx_mcdi *cdx = mcdi->cdx;531	u8 seq;532 533	if (!mcdi->db_held_by &&534	    cdx_mcdi_get_seq(mcdi, &seq)) {535		cmd->seq = seq;536		cmd->reboot_seen = false;537		cdx_mcdi_send_request(cdx, cmd);538		cmd->state = MCDI_STATE_RUNNING;539	} else {540		cmd->state = MCDI_STATE_QUEUED;541	}542}543 544/* try to advance other commands */545static void cdx_mcdi_start_or_queue(struct cdx_mcdi_iface *mcdi,546				    bool allow_retry)547{548	struct cdx_mcdi_cmd *cmd, *tmp;549 550	list_for_each_entry_safe(cmd, tmp, &mcdi->cmd_list, list)551		if (cmd->state == MCDI_STATE_QUEUED ||552		    (cmd->state == MCDI_STATE_RETRY && allow_retry))553			cdx_mcdi_cmd_start_or_queue(mcdi, cmd);554}555 556void cdx_mcdi_process_cmd(struct cdx_mcdi *cdx, struct cdx_dword *outbuf, int len)557{558	struct cdx_mcdi_iface *mcdi;559	struct cdx_mcdi_cmd *cmd;560	LIST_HEAD(cleanup_list);561	unsigned int respseq;562 563	if (!len || !outbuf) {564		pr_err("Got empty MC response\n");565		return;566	}567 568	mcdi = cdx_mcdi_if(cdx);569	if (!mcdi)570		return;571 572	respseq = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_SEQ);573 574	mutex_lock(&mcdi->iface_lock);575	cmd = mcdi->seq_held_by[respseq];576 577	if (cmd) {578		if (cmd->state == MCDI_STATE_FINISHED) {579			mutex_unlock(&mcdi->iface_lock);580			kref_put(&cmd->ref, cdx_mcdi_cmd_release);581			return;582		}583 584		cdx_mcdi_complete_cmd(mcdi, cmd, outbuf, len, &cleanup_list);585	} else {586		pr_err("MC response unexpected for seq : %0X\n", respseq);587	}588 589	mutex_unlock(&mcdi->iface_lock);590 591	cdx_mcdi_process_cleanup_list(mcdi->cdx, &cleanup_list);592}593 594static void cdx_mcdi_cmd_work(struct work_struct *context)595{596	struct cdx_mcdi_cmd *cmd =597		container_of(context, struct cdx_mcdi_cmd, work);598	struct cdx_mcdi_iface *mcdi = cmd->mcdi;599 600	mutex_lock(&mcdi->iface_lock);601 602	cmd->handle = mcdi->prev_handle++;603	list_add_tail(&cmd->list, &mcdi->cmd_list);604	cdx_mcdi_cmd_start_or_queue(mcdi, cmd);605 606	mutex_unlock(&mcdi->iface_lock);607}608 609/*610 * Returns true if the MCDI module is finished with the command.611 * (examples of false would be if the command was proxied, or it was612 * rejected by the MC due to lack of resources and requeued).613 */614static bool cdx_mcdi_complete_cmd(struct cdx_mcdi_iface *mcdi,615				  struct cdx_mcdi_cmd *cmd,616				  struct cdx_dword *outbuf,617				  int len,618				  struct list_head *cleanup_list)619{620	size_t resp_hdr_len, resp_data_len;621	struct cdx_mcdi *cdx = mcdi->cdx;622	unsigned int respcmd, error;623	bool completed = false;624	int rc;625 626	/* ensure the command can't go away before this function returns */627	kref_get(&cmd->ref);628 629	respcmd = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_CODE);630	error = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_ERROR);631 632	if (respcmd != MC_CMD_V2_EXTN) {633		resp_hdr_len = 4;634		resp_data_len = CDX_DWORD_FIELD(outbuf[0], MCDI_HEADER_DATALEN);635	} else {636		resp_data_len = 0;637		resp_hdr_len = 8;638		if (len >= 8)639			resp_data_len =640				CDX_DWORD_FIELD(outbuf[1], MC_CMD_V2_EXTN_IN_ACTUAL_LEN);641	}642 643	if ((resp_hdr_len + resp_data_len) > len) {644		pr_warn("Incomplete MCDI response received %d. Expected %zu\n",645			len, (resp_hdr_len + resp_data_len));646		resp_data_len = 0;647	}648 649	print_hex_dump_debug("MCDI RESP HEADER: ", DUMP_PREFIX_NONE, 32, 4,650			     outbuf, resp_hdr_len, false);651	print_hex_dump_debug("MCDI RESP PAYLOAD: ", DUMP_PREFIX_NONE, 32, 4,652			     outbuf + (resp_hdr_len / 4), resp_data_len, false);653 654	if (error && resp_data_len == 0) {655		/* MC rebooted during command */656		rc = -EIO;657	} else {658		if (WARN_ON_ONCE(error && resp_data_len < 4))659			resp_data_len = 4;660		if (error) {661			rc = CDX_DWORD_FIELD(outbuf[resp_hdr_len / 4], CDX_DWORD);662			if (!cmd->quiet) {663				int err_arg = 0;664 665				if (resp_data_len >= MC_CMD_ERR_ARG_OFST + 4) {666					int offset = (resp_hdr_len + MC_CMD_ERR_ARG_OFST) / 4;667 668					err_arg = CDX_DWORD_VAL(outbuf[offset]);669				}670 671				_cdx_mcdi_display_error(cdx, cmd->cmd,672							cmd->inlen, rc, err_arg,673							cdx_mcdi_errno(cdx, rc));674			}675			rc = cdx_mcdi_errno(cdx, rc);676		} else {677			rc = 0;678		}679	}680 681	/* free doorbell */682	if (mcdi->db_held_by == cmd)683		mcdi->db_held_by = NULL;684 685	if (cdx_cmd_cancelled(cmd)) {686		list_del(&cmd->list);687		kref_put(&cmd->ref, cdx_mcdi_cmd_release);688		completed = true;689	} else if (rc == MC_CMD_ERR_QUEUE_FULL) {690		cmd->state = MCDI_STATE_RETRY;691	} else {692		cmd->rc = rc;693		cmd->outbuf = outbuf + DIV_ROUND_UP(resp_hdr_len, 4);694		cmd->outlen = resp_data_len;695		cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);696		completed = true;697	}698 699	/* free sequence number and buffer */700	mcdi->seq_held_by[cmd->seq] = NULL;701 702	cdx_mcdi_start_or_queue(mcdi, rc != MC_CMD_ERR_QUEUE_FULL);703 704	/* wake up anyone waiting for flush */705	wake_up(&mcdi->cmd_complete_wq);706 707	kref_put(&cmd->ref, cdx_mcdi_cmd_release);708 709	return completed;710}711 712static void cdx_mcdi_timeout_cmd(struct cdx_mcdi_iface *mcdi,713				 struct cdx_mcdi_cmd *cmd,714				 struct list_head *cleanup_list)715{716	struct cdx_mcdi *cdx = mcdi->cdx;717 718	pr_err("MC command 0x%x inlen %zu state %d timed out after %u ms\n",719	       cmd->cmd, cmd->inlen, cmd->state,720	       jiffies_to_msecs(jiffies - cmd->started));721 722	cmd->rc = -ETIMEDOUT;723	cdx_mcdi_remove_cmd(mcdi, cmd, cleanup_list);724 725	cdx_mcdi_mode_fail(cdx, cleanup_list);726}727 728/**729 * cdx_mcdi_rpc - Issue an MCDI command and wait for completion730 * @cdx: NIC through which to issue the command731 * @cmd: Command type number732 * @inbuf: Command parameters733 * @inlen: Length of command parameters, in bytes. Must be a multiple734 *	of 4 and no greater than %MCDI_CTL_SDU_LEN_MAX_V1.735 * @outbuf: Response buffer. May be %NULL if @outlen is 0.736 * @outlen: Length of response buffer, in bytes. If the actual737 *	response is longer than @outlen & ~3, it will be truncated738 *	to that length.739 * @outlen_actual: Pointer through which to return the actual response740 *	length. May be %NULL if this is not needed.741 *742 * This function may sleep and therefore must be called in process743 * context.744 *745 * Return: A negative error code, or zero if successful. The error746 *	code may come from the MCDI response or may indicate a failure747 *	to communicate with the MC. In the former case, the response748 *	will still be copied to @outbuf and *@outlen_actual will be749 *	set accordingly. In the latter case, *@outlen_actual will be750 *	set to zero.751 */752int cdx_mcdi_rpc(struct cdx_mcdi *cdx, unsigned int cmd,753		 const struct cdx_dword *inbuf, size_t inlen,754		 struct cdx_dword *outbuf, size_t outlen,755		 size_t *outlen_actual)756{757	return cdx_mcdi_rpc_sync(cdx, cmd, inbuf, inlen, outbuf, outlen,758				 outlen_actual, false);759}760 761/**762 * cdx_mcdi_rpc_async - Schedule an MCDI command to run asynchronously763 * @cdx: NIC through which to issue the command764 * @cmd: Command type number765 * @inbuf: Command parameters766 * @inlen: Length of command parameters, in bytes767 * @complete: Function to be called on completion or cancellation.768 * @cookie: Arbitrary value to be passed to @complete.769 *770 * This function does not sleep and therefore may be called in atomic771 * context.  It will fail if event queues are disabled or if MCDI772 * event completions have been disabled due to an error.773 *774 * If it succeeds, the @complete function will be called exactly once775 * in process context, when one of the following occurs:776 * (a) the completion event is received (in process context)777 * (b) event queues are disabled (in the process that disables them)778 */779int780cdx_mcdi_rpc_async(struct cdx_mcdi *cdx, unsigned int cmd,781		   const struct cdx_dword *inbuf, size_t inlen,782		   cdx_mcdi_async_completer *complete, unsigned long cookie)783{784	struct cdx_mcdi_cmd *cmd_item =785		kmalloc(sizeof(struct cdx_mcdi_cmd) + inlen, GFP_ATOMIC);786 787	if (!cmd_item)788		return -ENOMEM;789 790	kref_init(&cmd_item->ref);791	cmd_item->quiet = true;792	cmd_item->cookie = cookie;793	cmd_item->completer = complete;794	cmd_item->cmd = cmd;795	cmd_item->inlen = inlen;796	/* inbuf is probably not valid after return, so take a copy */797	cmd_item->inbuf = (struct cdx_dword *)(cmd_item + 1);798	memcpy(cmd_item + 1, inbuf, inlen);799 800	return cdx_mcdi_rpc_async_internal(cdx, cmd_item, NULL);801}802 803static void _cdx_mcdi_display_error(struct cdx_mcdi *cdx, unsigned int cmd,804				    size_t inlen, int raw, int arg, int err_no)805{806	pr_err("MC command 0x%x inlen %d failed err_no=%d (raw=%d) arg=%d\n",807	       cmd, (int)inlen, err_no, raw, arg);808}809 810/*811 * Set MCDI mode to fail to prevent any new commands, then cancel any812 * outstanding commands.813 * Caller must hold the mcdi iface_lock.814 */815static void cdx_mcdi_mode_fail(struct cdx_mcdi *cdx, struct list_head *cleanup_list)816{817	struct cdx_mcdi_iface *mcdi = cdx_mcdi_if(cdx);818 819	if (!mcdi)820		return;821 822	mcdi->mode = MCDI_MODE_FAIL;823 824	while (!list_empty(&mcdi->cmd_list)) {825		struct cdx_mcdi_cmd *cmd;826 827		cmd = list_first_entry(&mcdi->cmd_list, struct cdx_mcdi_cmd,828				       list);829		_cdx_mcdi_cancel_cmd(mcdi, cdx_mcdi_cmd_handle(cmd), cleanup_list);830	}831}832