xref: /openbmc/linux/drivers/scsi/qla4xxx/ql4_iocb.c (revision a09d2831)
1 /*
2  * QLogic iSCSI HBA Driver
3  * Copyright (c)  2003-2006 QLogic Corporation
4  *
5  * See LICENSE.qla4xxx for copyright and licensing details.
6  */
7 
8 #include "ql4_def.h"
9 #include "ql4_glbl.h"
10 #include "ql4_dbg.h"
11 #include "ql4_inline.h"
12 
13 #include <scsi/scsi_tcq.h>
14 
15 static int
16 qla4xxx_space_in_req_ring(struct scsi_qla_host *ha, uint16_t req_cnt)
17 {
18 	uint16_t cnt;
19 
20 	/* Calculate number of free request entries. */
21 	if ((req_cnt + 2) >= ha->req_q_count) {
22 		cnt = (uint16_t) le32_to_cpu(ha->shadow_regs->req_q_out);
23 		if (ha->request_in < cnt)
24 			ha->req_q_count = cnt - ha->request_in;
25 		else
26 			ha->req_q_count = REQUEST_QUEUE_DEPTH -
27 						(ha->request_in - cnt);
28 	}
29 
30 	/* Check if room for request in request ring. */
31 	if ((req_cnt + 2) < ha->req_q_count)
32 		return 1;
33 	else
34 		return 0;
35 }
36 
37 static void qla4xxx_advance_req_ring_ptr(struct scsi_qla_host *ha)
38 {
39 	/* Advance request queue pointer */
40 	if (ha->request_in == (REQUEST_QUEUE_DEPTH - 1)) {
41 		ha->request_in = 0;
42 		ha->request_ptr = ha->request_ring;
43 	} else {
44 		ha->request_in++;
45 		ha->request_ptr++;
46 	}
47 }
48 
49 /**
50  * qla4xxx_get_req_pkt - returns a valid entry in request queue.
51  * @ha: Pointer to host adapter structure.
52  * @queue_entry: Pointer to pointer to queue entry structure
53  *
54  * This routine performs the following tasks:
55  *	- returns the current request_in pointer (if queue not full)
56  *	- advances the request_in pointer
57  *	- checks for queue full
58  **/
59 static int qla4xxx_get_req_pkt(struct scsi_qla_host *ha,
60 			       struct queue_entry **queue_entry)
61 {
62 	uint16_t req_cnt = 1;
63 
64 	if (qla4xxx_space_in_req_ring(ha, req_cnt)) {
65 		*queue_entry = ha->request_ptr;
66 		memset(*queue_entry, 0, sizeof(**queue_entry));
67 
68 		qla4xxx_advance_req_ring_ptr(ha);
69 		ha->req_q_count -= req_cnt;
70 		return QLA_SUCCESS;
71 	}
72 
73 	return QLA_ERROR;
74 }
75 
76 /**
77  * qla4xxx_send_marker_iocb - issues marker iocb to HBA
78  * @ha: Pointer to host adapter structure.
79  * @ddb_entry: Pointer to device database entry
80  * @lun: SCSI LUN
81  * @marker_type: marker identifier
82  *
83  * This routine issues a marker IOCB.
84  **/
85 int qla4xxx_send_marker_iocb(struct scsi_qla_host *ha,
86 	struct ddb_entry *ddb_entry, int lun, uint16_t mrkr_mod)
87 {
88 	struct qla4_marker_entry *marker_entry;
89 	unsigned long flags = 0;
90 	uint8_t status = QLA_SUCCESS;
91 
92 	/* Acquire hardware specific lock */
93 	spin_lock_irqsave(&ha->hardware_lock, flags);
94 
95 	/* Get pointer to the queue entry for the marker */
96 	if (qla4xxx_get_req_pkt(ha, (struct queue_entry **) &marker_entry) !=
97 	    QLA_SUCCESS) {
98 		status = QLA_ERROR;
99 		goto exit_send_marker;
100 	}
101 
102 	/* Put the marker in the request queue */
103 	marker_entry->hdr.entryType = ET_MARKER;
104 	marker_entry->hdr.entryCount = 1;
105 	marker_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
106 	marker_entry->modifier = cpu_to_le16(mrkr_mod);
107 	int_to_scsilun(lun, &marker_entry->lun);
108 	wmb();
109 
110 	/* Tell ISP it's got a new I/O request */
111 	writel(ha->request_in, &ha->reg->req_q_in);
112 	readl(&ha->reg->req_q_in);
113 
114 exit_send_marker:
115 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
116 	return status;
117 }
118 
119 static struct continuation_t1_entry *
120 qla4xxx_alloc_cont_entry(struct scsi_qla_host *ha)
121 {
122 	struct continuation_t1_entry *cont_entry;
123 
124 	cont_entry = (struct continuation_t1_entry *)ha->request_ptr;
125 
126 	qla4xxx_advance_req_ring_ptr(ha);
127 
128 	/* Load packet defaults */
129 	cont_entry->hdr.entryType = ET_CONTINUE;
130 	cont_entry->hdr.entryCount = 1;
131 	cont_entry->hdr.systemDefined = (uint8_t) cpu_to_le16(ha->request_in);
132 
133 	return cont_entry;
134 }
135 
136 static uint16_t qla4xxx_calc_request_entries(uint16_t dsds)
137 {
138 	uint16_t iocbs;
139 
140 	iocbs = 1;
141 	if (dsds > COMMAND_SEG) {
142 		iocbs += (dsds - COMMAND_SEG) / CONTINUE_SEG;
143 		if ((dsds - COMMAND_SEG) % CONTINUE_SEG)
144 			iocbs++;
145 	}
146 	return iocbs;
147 }
148 
149 static void qla4xxx_build_scsi_iocbs(struct srb *srb,
150 				     struct command_t3_entry *cmd_entry,
151 				     uint16_t tot_dsds)
152 {
153 	struct scsi_qla_host *ha;
154 	uint16_t avail_dsds;
155 	struct data_seg_a64 *cur_dsd;
156 	struct scsi_cmnd *cmd;
157 	struct scatterlist *sg;
158 	int i;
159 
160 	cmd = srb->cmd;
161 	ha = srb->ha;
162 
163 	if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
164 		/* No data being transferred */
165 		cmd_entry->ttlByteCnt = __constant_cpu_to_le32(0);
166 		return;
167 	}
168 
169 	avail_dsds = COMMAND_SEG;
170 	cur_dsd = (struct data_seg_a64 *) & (cmd_entry->dataseg[0]);
171 
172 	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
173 		dma_addr_t sle_dma;
174 
175 		/* Allocate additional continuation packets? */
176 		if (avail_dsds == 0) {
177 			struct continuation_t1_entry *cont_entry;
178 
179 			cont_entry = qla4xxx_alloc_cont_entry(ha);
180 			cur_dsd =
181 				(struct data_seg_a64 *)
182 				&cont_entry->dataseg[0];
183 			avail_dsds = CONTINUE_SEG;
184 		}
185 
186 		sle_dma = sg_dma_address(sg);
187 		cur_dsd->base.addrLow = cpu_to_le32(LSDW(sle_dma));
188 		cur_dsd->base.addrHigh = cpu_to_le32(MSDW(sle_dma));
189 		cur_dsd->count = cpu_to_le32(sg_dma_len(sg));
190 		avail_dsds--;
191 
192 		cur_dsd++;
193 	}
194 }
195 
196 /**
197  * qla4xxx_send_command_to_isp - issues command to HBA
198  * @ha: pointer to host adapter structure.
199  * @srb: pointer to SCSI Request Block to be sent to ISP
200  *
201  * This routine is called by qla4xxx_queuecommand to build an ISP
202  * command and pass it to the ISP for execution.
203  **/
204 int qla4xxx_send_command_to_isp(struct scsi_qla_host *ha, struct srb * srb)
205 {
206 	struct scsi_cmnd *cmd = srb->cmd;
207 	struct ddb_entry *ddb_entry;
208 	struct command_t3_entry *cmd_entry;
209 	int nseg;
210 	uint16_t tot_dsds;
211 	uint16_t req_cnt;
212 	unsigned long flags;
213 	uint32_t index;
214 	char tag[2];
215 
216 	/* Get real lun and adapter */
217 	ddb_entry = srb->ddb;
218 
219 	tot_dsds = 0;
220 
221 	/* Acquire hardware specific lock */
222 	spin_lock_irqsave(&ha->hardware_lock, flags);
223 
224 	index = (uint32_t)cmd->request->tag;
225 
226 	/*
227 	 * Check to see if adapter is online before placing request on
228 	 * request queue.  If a reset occurs and a request is in the queue,
229 	 * the firmware will still attempt to process the request, retrieving
230 	 * garbage for pointers.
231 	 */
232 	if (!test_bit(AF_ONLINE, &ha->flags)) {
233 		DEBUG2(printk("scsi%ld: %s: Adapter OFFLINE! "
234 			      "Do not issue command.\n",
235 			      ha->host_no, __func__));
236 		goto queuing_error;
237 	}
238 
239 	/* Calculate the number of request entries needed. */
240 	nseg = scsi_dma_map(cmd);
241 	if (nseg < 0)
242 		goto queuing_error;
243 	tot_dsds = nseg;
244 
245 	req_cnt = qla4xxx_calc_request_entries(tot_dsds);
246 	if (!qla4xxx_space_in_req_ring(ha, req_cnt))
247 		goto queuing_error;
248 
249 	/* total iocbs active */
250 	if ((ha->iocb_cnt + req_cnt) >= REQUEST_QUEUE_DEPTH)
251 		goto queuing_error;
252 
253 	/* Build command packet */
254 	cmd_entry = (struct command_t3_entry *) ha->request_ptr;
255 	memset(cmd_entry, 0, sizeof(struct command_t3_entry));
256 	cmd_entry->hdr.entryType = ET_COMMAND;
257 	cmd_entry->handle = cpu_to_le32(index);
258 	cmd_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
259 	cmd_entry->connection_id = cpu_to_le16(ddb_entry->connection_id);
260 
261 	int_to_scsilun(cmd->device->lun, &cmd_entry->lun);
262 	cmd_entry->cmdSeqNum = cpu_to_le32(ddb_entry->CmdSn);
263 	cmd_entry->ttlByteCnt = cpu_to_le32(scsi_bufflen(cmd));
264 	memcpy(cmd_entry->cdb, cmd->cmnd, cmd->cmd_len);
265 	cmd_entry->dataSegCnt = cpu_to_le16(tot_dsds);
266 	cmd_entry->hdr.entryCount = req_cnt;
267 
268 	/* Set data transfer direction control flags
269 	 * NOTE: Look at data_direction bits iff there is data to be
270 	 *	 transferred, as the data direction bit is sometimed filled
271 	 *	 in when there is no data to be transferred */
272 	cmd_entry->control_flags = CF_NO_DATA;
273 	if (scsi_bufflen(cmd)) {
274 		if (cmd->sc_data_direction == DMA_TO_DEVICE)
275 			cmd_entry->control_flags = CF_WRITE;
276 		else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
277 			cmd_entry->control_flags = CF_READ;
278 
279 		ha->bytes_xfered += scsi_bufflen(cmd);
280 		if (ha->bytes_xfered & ~0xFFFFF){
281 			ha->total_mbytes_xferred += ha->bytes_xfered >> 20;
282 			ha->bytes_xfered &= 0xFFFFF;
283 		}
284 	}
285 
286 	/* Set tagged queueing control flags */
287 	cmd_entry->control_flags |= CF_SIMPLE_TAG;
288 	if (scsi_populate_tag_msg(cmd, tag))
289 		switch (tag[0]) {
290 		case MSG_HEAD_TAG:
291 			cmd_entry->control_flags |= CF_HEAD_TAG;
292 			break;
293 		case MSG_ORDERED_TAG:
294 			cmd_entry->control_flags |= CF_ORDERED_TAG;
295 			break;
296 		}
297 
298 	qla4xxx_advance_req_ring_ptr(ha);
299 	qla4xxx_build_scsi_iocbs(srb, cmd_entry, tot_dsds);
300 	wmb();
301 
302 	srb->cmd->host_scribble = (unsigned char *)srb;
303 
304 	/* update counters */
305 	srb->state = SRB_ACTIVE_STATE;
306 	srb->flags |= SRB_DMA_VALID;
307 
308 	/* Track IOCB used */
309 	ha->iocb_cnt += req_cnt;
310 	srb->iocb_cnt = req_cnt;
311 	ha->req_q_count -= req_cnt;
312 
313 	/* Debug print statements */
314 	writel(ha->request_in, &ha->reg->req_q_in);
315 	readl(&ha->reg->req_q_in);
316 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
317 
318 	return QLA_SUCCESS;
319 
320 queuing_error:
321 	if (tot_dsds)
322 		scsi_dma_unmap(cmd);
323 
324 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
325 
326 	return QLA_ERROR;
327 }
328 
329