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#include "host.h"
57#include "unsolicited_frame_control.h"
58#include "registers.h"
59
60void sci_unsolicited_frame_control_construct(struct isci_host *ihost)
61{
62 struct sci_unsolicited_frame_control *uf_control = &ihost->uf_control;
63 struct sci_unsolicited_frame *uf;
64 dma_addr_t dma = ihost->ufi_dma;
65 void *virt = ihost->ufi_buf;
66 int i;
67
68 /*
69 * The Unsolicited Frame buffers are set at the start of the UF
70 * memory descriptor entry. The headers and address table will be
71 * placed after the buffers.
72 */
73
74 /*
75 * Program the location of the UF header table into the SCU.
76 * Notes:
77 * - The address must align on a 64-byte boundary. Guaranteed to be
78 * on 64-byte boundary already 1KB boundary for unsolicited frames.
79 * - Program unused header entries to overlap with the last
80 * unsolicited frame. The silicon will never DMA to these unused
81 * headers, since we program the UF address table pointers to
82 * NULL.
83 */
84 uf_control->headers.physical_address = dma + SCI_UFI_BUF_SIZE;
85 uf_control->headers.array = virt + SCI_UFI_BUF_SIZE;
86
87 /*
88 * Program the location of the UF address table into the SCU.
89 * Notes:
90 * - The address must align on a 64-bit boundary. Guaranteed to be on 64
91 * byte boundary already due to above programming headers being on a
92 * 64-bit boundary and headers are on a 64-bytes in size.
93 */
94 uf_control->address_table.physical_address = dma + SCI_UFI_BUF_SIZE + SCI_UFI_HDR_SIZE;
95 uf_control->address_table.array = virt + SCI_UFI_BUF_SIZE + SCI_UFI_HDR_SIZE;
96 uf_control->get = 0;
97
98 /*
99 * UF buffer requirements are:
100 * - The last entry in the UF queue is not NULL.
101 * - There is a power of 2 number of entries (NULL or not-NULL)
102 * programmed into the queue.
103 * - Aligned on a 1KB boundary. */
104
105 /*
106 * Program the actual used UF buffers into the UF address table and
107 * the controller's array of UFs.
108 */
109 for (i = 0; i < SCU_MAX_UNSOLICITED_FRAMES; i++) {
110 uf = &uf_control->buffers.array[i];
111
112 uf_control->address_table.array[i] = dma;
113
114 uf->buffer = virt;
115 uf->header = &uf_control->headers.array[i];
116 uf->state = UNSOLICITED_FRAME_EMPTY;
117
118 /*
119 * Increment the address of the physical and virtual memory
120 * pointers. Everything is aligned on 1k boundary with an
121 * increment of 1k.
122 */
123 virt += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
124 dma += SCU_UNSOLICITED_FRAME_BUFFER_SIZE;
125 }
126}
127
128enum sci_status sci_unsolicited_frame_control_get_header(struct sci_unsolicited_frame_control *uf_control,
129 u32 frame_index,
130 void **frame_header)
131{
132 if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) {
133 /* Skip the first word in the frame since this is a controll word used
134 * by the hardware.
135 */
136 *frame_header = &uf_control->buffers.array[frame_index].header->data;
137
138 return SCI_SUCCESS;
139 }
140
141 return SCI_FAILURE_INVALID_PARAMETER_VALUE;
142}
143
144enum sci_status sci_unsolicited_frame_control_get_buffer(struct sci_unsolicited_frame_control *uf_control,
145 u32 frame_index,
146 void **frame_buffer)
147{
148 if (frame_index < SCU_MAX_UNSOLICITED_FRAMES) {
149 *frame_buffer = uf_control->buffers.array[frame_index].buffer;
150
151 return SCI_SUCCESS;
152 }
153
154 return SCI_FAILURE_INVALID_PARAMETER_VALUE;
155}
156
157bool sci_unsolicited_frame_control_release_frame(struct sci_unsolicited_frame_control *uf_control,
158 u32 frame_index)
159{
160 u32 frame_get;
161 u32 frame_cycle;
162
163 frame_get = uf_control->get & (SCU_MAX_UNSOLICITED_FRAMES - 1);
164 frame_cycle = uf_control->get & SCU_MAX_UNSOLICITED_FRAMES;
165
166 /*
167 * In the event there are NULL entries in the UF table, we need to
168 * advance the get pointer in order to find out if this frame should
169 * be released (i.e. update the get pointer)
170 */
171 while (lower_32_bits(uf_control->address_table.array[frame_get]) == 0 &&
172 upper_32_bits(uf_control->address_table.array[frame_get]) == 0 &&
173 frame_get < SCU_MAX_UNSOLICITED_FRAMES)
174 frame_get++;
175
176 /*
177 * The table has a NULL entry as it's last element. This is
178 * illegal.
179 */
180 BUG_ON(frame_get >= SCU_MAX_UNSOLICITED_FRAMES);
181 if (frame_index >= SCU_MAX_UNSOLICITED_FRAMES)
182 return false;
183
184 uf_control->buffers.array[frame_index].state = UNSOLICITED_FRAME_RELEASED;
185
186 if (frame_get != frame_index) {
187 /*
188 * Frames remain in use until we advance the get pointer
189 * so there is nothing we can do here
190 */
191 return false;
192 }
193
194 /*
195 * The frame index is equal to the current get pointer so we
196 * can now free up all of the frame entries that
197 */
198 while (uf_control->buffers.array[frame_get].state == UNSOLICITED_FRAME_RELEASED) {
199 uf_control->buffers.array[frame_get].state = UNSOLICITED_FRAME_EMPTY;
200
201 if (frame_get+1 == SCU_MAX_UNSOLICITED_FRAMES-1) {
202 frame_cycle ^= SCU_MAX_UNSOLICITED_FRAMES;
203 frame_get = 0;
204 } else
205 frame_get++;
206 }
207
208 uf_control->get = SCU_UFQGP_GEN_BIT(ENABLE_BIT) | frame_cycle | frame_get;
209
210 return true;
211}
212

source code of linux/drivers/scsi/isci/unsolicited_frame_control.c