xref: /linux/drivers/scsi/isci/remote_node_context.h (revision e5451c8f8330e03ad3cfa16048b4daf961af434f)
1 /*
2  * This file is provided under a dual BSD/GPLv2 license.  When using or
3  * redistributing this file, you may do so under either license.
4  *
5  * GPL LICENSE SUMMARY
6  *
7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of version 2 of the GNU General Public License as
11  * published by the Free Software Foundation.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
21  * The full GNU General Public License is included in this distribution
22  * in the file called LICENSE.GPL.
23  *
24  * BSD LICENSE
25  *
26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
27  * All rights reserved.
28  *
29  * Redistribution and use in source and binary forms, with or without
30  * modification, are permitted provided that the following conditions
31  * are met:
32  *
33  *   * Redistributions of source code must retain the above copyright
34  *     notice, this list of conditions and the following disclaimer.
35  *   * Redistributions in binary form must reproduce the above copyright
36  *     notice, this list of conditions and the following disclaimer in
37  *     the documentation and/or other materials provided with the
38  *     distribution.
39  *   * Neither the name of Intel Corporation nor the names of its
40  *     contributors may be used to endorse or promote products derived
41  *     from this software without specific prior written permission.
42  *
43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
54  */
55 
56 #ifndef _SCIC_SDS_REMOTE_NODE_CONTEXT_H_
57 #define _SCIC_SDS_REMOTE_NODE_CONTEXT_H_
58 
59 /**
60  * This file contains the structures, constants, and prototypes associated with
61  *    the remote node context in the silicon.  It exists to model and manage
62  *    the remote node context in the silicon.
63  *
64  *
65  */
66 
67 #include "isci.h"
68 
69 /**
70  *
71  *
72  * This constant represents an invalid remote device id, it is used to program
73  * the STPDARNI register so the driver knows when it has received a SIGNATURE
74  * FIS from the SCU.
75  */
76 #define SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX    0x0FFF
77 
78 enum sci_remote_node_suspension_reasons {
79 	SCI_HW_SUSPEND,
80 	SCI_SW_SUSPEND_NORMAL,
81 	SCI_SW_SUSPEND_LINKHANG_DETECT
82 };
83 #define SCI_SOFTWARE_SUSPEND_CMD SCU_CONTEXT_COMMAND_POST_RNC_SUSPEND_TX_RX
84 #define SCI_SOFTWARE_SUSPEND_EXPECTED_EVENT SCU_EVENT_TL_RNC_SUSPEND_TX_RX
85 
86 struct isci_request;
87 struct isci_remote_device;
88 struct sci_remote_node_context;
89 
90 typedef void (*scics_sds_remote_node_context_callback)(void *);
91 
92 /**
93  * enum sci_remote_node_context_states
94  * @SCI_RNC_INITIAL initial state for a remote node context.  On a resume
95  * request the remote node context will transition to the posting state.
96  *
97  * @SCI_RNC_POSTING: transition state that posts the RNi to the hardware. Once
98  * the RNC is posted the remote node context will be made ready.
99  *
100  * @SCI_RNC_INVALIDATING: transition state that will post an RNC invalidate to
101  * the hardware.  Once the invalidate is complete the remote node context will
102  * transition to the posting state.
103  *
104  * @SCI_RNC_RESUMING: transition state that will post an RNC resume to the
105  * hardare.  Once the event notification of resume complete is received the
106  * remote node context will transition to the ready state.
107  *
108  * @SCI_RNC_READY: state that the remote node context must be in to accept io
109  * request operations.
110  *
111  * @SCI_RNC_TX_SUSPENDED: state that the remote node context transitions to when
112  * it gets a TX suspend notification from the hardware.
113  *
114  * @SCI_RNC_TX_RX_SUSPENDED: state that the remote node context transitions to
115  * when it gets a TX RX suspend notification from the hardware.
116  *
117  * @SCI_RNC_AWAIT_SUSPENSION: wait state for the remote node context that waits
118  * for a suspend notification from the hardware.  This state is entered when
119  * either there is a request to supend the remote node context or when there is
120  * a TC completion where the remote node will be suspended by the hardware.
121  */
122 #define RNC_STATES {\
123 	C(RNC_INITIAL),\
124 	C(RNC_POSTING),\
125 	C(RNC_INVALIDATING),\
126 	C(RNC_RESUMING),\
127 	C(RNC_READY),\
128 	C(RNC_TX_SUSPENDED),\
129 	C(RNC_TX_RX_SUSPENDED),\
130 	C(RNC_AWAIT_SUSPENSION),\
131 	}
132 #undef C
133 #define C(a) SCI_##a
134 enum scis_sds_remote_node_context_states RNC_STATES;
135 #undef C
136 const char *rnc_state_name(enum scis_sds_remote_node_context_states state);
137 
138 /**
139  *
140  *
141  * This enumeration is used to define the end destination state for the remote
142  * node context.
143  */
144 enum sci_remote_node_context_destination_state {
145 	RNC_DEST_UNSPECIFIED,
146 	RNC_DEST_READY,
147 	RNC_DEST_FINAL,
148 	RNC_DEST_SUSPENDED,       /* Set when suspend during post/invalidate */
149 	RNC_DEST_SUSPENDED_RESUME /* Set when a resume was done during posting
150 				   * or invalidating and already suspending.
151 				   */
152 };
153 
154 /**
155  * struct sci_remote_node_context - This structure contains the data
156  *    associated with the remote node context object.  The remote node context
157  *    (RNC) object models the the remote device information necessary to manage
158  *    the silicon RNC.
159  */
160 struct sci_remote_node_context {
161 	/**
162 	 * This field indicates the remote node index (RNI) associated with
163 	 * this RNC.
164 	 */
165 	u16 remote_node_index;
166 
167 	/**
168 	 * This field is the recored suspension type of the remote node
169 	 * context suspension.
170 	 */
171 	u32 suspend_type;
172 	enum sci_remote_node_suspension_reasons suspend_reason;
173 	u32 suspend_count;
174 
175 	/**
176 	 * This field is true if the remote node context is resuming from its current
177 	 * state.  This can cause an automatic resume on receiving a suspension
178 	 * notification.
179 	 */
180 	enum sci_remote_node_context_destination_state destination_state;
181 
182 	/**
183 	 * This field contains the callback function that the user requested to be
184 	 * called when the requested state transition is complete.
185 	 */
186 	scics_sds_remote_node_context_callback user_callback;
187 
188 	/**
189 	 * This field contains the parameter that is called when the user requested
190 	 * state transition is completed.
191 	 */
192 	void *user_cookie;
193 
194 	/**
195 	 * This field contains the data for the object's state machine.
196 	 */
197 	struct sci_base_state_machine sm;
198 };
199 
200 void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
201 					    u16 remote_node_index);
202 
203 
204 bool sci_remote_node_context_is_ready(
205 	struct sci_remote_node_context *sci_rnc);
206 
207 bool sci_remote_node_context_is_suspended(struct sci_remote_node_context *sci_rnc);
208 
209 enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
210 							   u32 event_code);
211 enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
212 						      scics_sds_remote_node_context_callback callback,
213 						      void *callback_parameter);
214 enum sci_status sci_remote_node_context_suspend(struct sci_remote_node_context *sci_rnc,
215 						     enum sci_remote_node_suspension_reasons reason,
216 						     u32 suspension_code);
217 enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
218 						    scics_sds_remote_node_context_callback cb_fn,
219 						    void *cb_p);
220 enum sci_status sci_remote_node_context_start_task(struct sci_remote_node_context *sci_rnc,
221 						   struct isci_request *ireq,
222 						   scics_sds_remote_node_context_callback cb_fn,
223 						   void *cb_p);
224 enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
225 						      struct isci_request *ireq);
226 int sci_remote_node_context_is_safe_to_abort(
227 	struct sci_remote_node_context *sci_rnc);
228 
sci_remote_node_context_is_being_destroyed(struct sci_remote_node_context * sci_rnc)229 static inline bool sci_remote_node_context_is_being_destroyed(
230 	struct sci_remote_node_context *sci_rnc)
231 {
232 	return (sci_rnc->destination_state == RNC_DEST_FINAL)
233 		|| ((sci_rnc->sm.current_state_id == SCI_RNC_INITIAL)
234 		    && (sci_rnc->destination_state == RNC_DEST_UNSPECIFIED));
235 }
236 #endif  /* _SCIC_SDS_REMOTE_NODE_CONTEXT_H_ */
237