response_manager.c

  1/**********************************************************************
  2 * Author: Cavium, Inc.
  3 *
  4 * Contact: support@cavium.com
  5 *          Please include "LiquidIO" in the subject.
  6 *
  7 * Copyright (c) 2003-2016 Cavium, Inc.
  8 *
  9 * This file is free software; you can redistribute it and/or modify
 10 * it under the terms of the GNU General Public License, Version 2, as
 11 * published by the Free Software Foundation.
 12 *
 13 * This file is distributed in the hope that it will be useful, but
 14 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
 15 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
 16 * NONINFRINGEMENT.  See the GNU General Public License for more
 17 * details.
 18 **********************************************************************/
 19#include <linux/pci.h>
 20#include <linux/netdevice.h>
 21#include "liquidio_common.h"
 22#include "octeon_droq.h"
 23#include "octeon_iq.h"
 24#include "response_manager.h"
 25#include "octeon_device.h"
 26#include "octeon_main.h"
 27
 28static void oct_poll_req_completion(struct work_struct *work);
 29
 30int octeon_setup_response_list(struct octeon_device *oct)
 31{
 32	int i, ret = 0;
 33	struct cavium_wq *cwq;
 34
 35	for (i = 0; i < MAX_RESPONSE_LISTS; i++) {
 36		INIT_LIST_HEAD(&oct->response_list[i].head);
 37		spin_lock_init(&oct->response_list[i].lock);
 38		atomic_set(&oct->response_list[i].pending_req_count, 0);
 39	}
 40	spin_lock_init(&oct->cmd_resp_wqlock);
 41
 42	oct->dma_comp_wq.wq = alloc_workqueue("dma-comp",
 43					      WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 44	if (!oct->dma_comp_wq.wq) {
 45		dev_err(&oct->pci_dev->dev, "failed to create wq thread\n");
 46		return -ENOMEM;
 47	}
 48
 49	cwq = &oct->dma_comp_wq;
 50	INIT_DELAYED_WORK(&cwq->wk.work, oct_poll_req_completion);
 51	cwq->wk.ctxptr = oct;
 52	oct->cmd_resp_state = OCT_DRV_ONLINE;
 53
 54	return ret;
 55}
 56EXPORT_SYMBOL_GPL(octeon_setup_response_list);
 57
 58void octeon_delete_response_list(struct octeon_device *oct)
 59{
 60	cancel_delayed_work_sync(&oct->dma_comp_wq.wk.work);
 61	destroy_workqueue(oct->dma_comp_wq.wq);
 62}
 63EXPORT_SYMBOL_GPL(octeon_delete_response_list);
 64
 65int lio_process_ordered_list(struct octeon_device *octeon_dev,
 66			     u32 force_quit)
 67{
 68	struct octeon_response_list *ordered_sc_list;
 69	struct octeon_soft_command *sc;
 70	int request_complete = 0;
 71	int resp_to_process = MAX_ORD_REQS_TO_PROCESS;
 72	u32 status;
 73	u64 status64;
 74
 75	octeon_free_sc_done_list(octeon_dev);
 76
 77	ordered_sc_list = &octeon_dev->response_list[OCTEON_ORDERED_SC_LIST];
 78
 79	do {
 80		spin_lock_bh(&ordered_sc_list->lock);
 81
 82		if (list_empty(&ordered_sc_list->head)) {
 83			spin_unlock_bh(&ordered_sc_list->lock);
 84			return 1;
 85		}
 86
 87		sc = list_first_entry(&ordered_sc_list->head,
 88				      struct octeon_soft_command, node);
 89
 90		status = OCTEON_REQUEST_PENDING;
 91
 92		/* check if octeon has finished DMA'ing a response
 93		 * to where rptr is pointing to
 94		 */
 95		status64 = *sc->status_word;
 96
 97		if (status64 != COMPLETION_WORD_INIT) {
 98			/* This logic ensures that all 64b have been written.
 99			 * 1. check byte 0 for non-FF
100			 * 2. if non-FF, then swap result from BE to host order
101			 * 3. check byte 7 (swapped to 0) for non-FF
102			 * 4. if non-FF, use the low 32-bit status code
103			 * 5. if either byte 0 or byte 7 is FF, don't use status
104			 */
105			if ((status64 & 0xff) != 0xff) {
106				octeon_swap_8B_data(&status64, 1);
107				if (((status64 & 0xff) != 0xff)) {
108					/* retrieve 16-bit firmware status */
109					status = (u32)(status64 & 0xffffULL);
110					if (status) {
111						status =
112						  FIRMWARE_STATUS_CODE(status);
113					} else {
114						/* i.e. no error */
115						status = OCTEON_REQUEST_DONE;
116					}
117				}
118			}
119		} else if (unlikely(force_quit) || (sc->expiry_time &&
120			time_after(jiffies, (unsigned long)sc->expiry_time))) {
121			struct octeon_instr_irh *irh =
122				(struct octeon_instr_irh *)&sc->cmd.cmd3.irh;
123
124			dev_err(&octeon_dev->pci_dev->dev, "%s: ", __func__);
125			dev_err(&octeon_dev->pci_dev->dev,
126				"cmd %x/%x/%llx/%llx failed, ",
127				irh->opcode, irh->subcode,
128				sc->cmd.cmd3.ossp[0], sc->cmd.cmd3.ossp[1]);
129			dev_err(&octeon_dev->pci_dev->dev,
130				"timeout (%ld, %ld)\n",
131				(long)jiffies, (long)sc->expiry_time);
132			status = OCTEON_REQUEST_TIMEOUT;
133		}
134
135		if (status != OCTEON_REQUEST_PENDING) {
136			sc->sc_status = status;
137
138			/* we have received a response or we have timed out */
139			/* remove node from linked list */
140			list_del(&sc->node);
141			atomic_dec(&octeon_dev->response_list
142				   [OCTEON_ORDERED_SC_LIST].
143				   pending_req_count);
144
145			if (!sc->callback) {
146				atomic_inc(&octeon_dev->response_list
147					   [OCTEON_DONE_SC_LIST].
148					   pending_req_count);
149				list_add_tail(&sc->node,
150					      &octeon_dev->response_list
151					      [OCTEON_DONE_SC_LIST].head);
152
153				if (unlikely(READ_ONCE(sc->caller_is_done))) {
154					/* caller does not wait for response
155					 * from firmware
156					 */
157					if (status != OCTEON_REQUEST_DONE) {
158						struct octeon_instr_irh *irh;
159
160						irh =
161						    (struct octeon_instr_irh *)
162						    &sc->cmd.cmd3.irh;
163						dev_dbg
164						    (&octeon_dev->pci_dev->dev,
165						    "%s: sc failed: opcode=%x, ",
166						    __func__, irh->opcode);
167						dev_dbg
168						    (&octeon_dev->pci_dev->dev,
169						    "subcode=%x, ossp[0]=%llx, ",
170						    irh->subcode,
171						    sc->cmd.cmd3.ossp[0]);
172						dev_dbg
173						    (&octeon_dev->pci_dev->dev,
174						    "ossp[1]=%llx, status=%d\n",
175						    sc->cmd.cmd3.ossp[1],
176						    status);
177					}
178				} else {
179					complete(&sc->complete);
180				}
181
182				spin_unlock_bh(&ordered_sc_list->lock);
183			} else {
184				/* sc with callback function */
185				if (status == OCTEON_REQUEST_TIMEOUT) {
186					atomic_inc(&octeon_dev->response_list
187						   [OCTEON_ZOMBIE_SC_LIST].
188						   pending_req_count);
189					list_add_tail(&sc->node,
190						      &octeon_dev->response_list
191						      [OCTEON_ZOMBIE_SC_LIST].
192						      head);
193				}
194
195				spin_unlock_bh(&ordered_sc_list->lock);
196
197				sc->callback(octeon_dev, status,
198					     sc->callback_arg);
199				/* sc is freed by caller */
200			}
201
202			request_complete++;
203
204		} else {
205			/* no response yet */
206			request_complete = 0;
207			spin_unlock_bh
208			    (&ordered_sc_list->lock);
209		}
210
211		/* If we hit the Max Ordered requests to process every loop,
212		 * we quit
213		 * and let this function be invoked the next time the poll
214		 * thread runs
215		 * to process the remaining requests. This function can take up
216		 * the entire CPU if there is no upper limit to the requests
217		 * processed.
218		 */
219		if (request_complete >= resp_to_process)
220			break;
221	} while (request_complete);
222
223	return 0;
224}
225EXPORT_SYMBOL_GPL(lio_process_ordered_list);
226
227static void oct_poll_req_completion(struct work_struct *work)
228{
229	struct cavium_wk *wk = (struct cavium_wk *)work;
230	struct octeon_device *oct = (struct octeon_device *)wk->ctxptr;
231	struct cavium_wq *cwq = &oct->dma_comp_wq;
232
233	lio_process_ordered_list(oct, 0);
234
235	if (atomic_read(&oct->response_list
236			[OCTEON_ORDERED_SC_LIST].pending_req_count))
237		queue_delayed_work(cwq->wq, &cwq->wk.work, msecs_to_jiffies(1));
238}