1 /*
2  * Serial Attached SCSI (SAS) Expander discovery and configuration
3  *
4  * Copyright (C) 2007 James E.J. Bottomley
5  *		<James.Bottomley@HansenPartnership.com>
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License as
9  * published by the Free Software Foundation; version 2 only.
10  */
11 #include <linux/scatterlist.h>
12 #include <linux/blkdev.h>
13 
14 #include "sas_internal.h"
15 
16 #include <scsi/scsi_transport.h>
17 #include <scsi/scsi_transport_sas.h>
18 #include "../scsi_sas_internal.h"
19 
20 static void sas_host_smp_discover(struct sas_ha_struct *sas_ha, u8 *resp_data,
21 				  u8 phy_id)
22 {
23 	struct sas_phy *phy;
24 	struct sas_rphy *rphy;
25 
26 	if (phy_id >= sas_ha->num_phys) {
27 		resp_data[2] = SMP_RESP_NO_PHY;
28 		return;
29 	}
30 	resp_data[2] = SMP_RESP_FUNC_ACC;
31 
32 	phy = sas_ha->sas_phy[phy_id]->phy;
33 	resp_data[9] = phy_id;
34 	resp_data[13] = phy->negotiated_linkrate;
35 	memcpy(resp_data + 16, sas_ha->sas_addr, SAS_ADDR_SIZE);
36 	memcpy(resp_data + 24, sas_ha->sas_phy[phy_id]->attached_sas_addr,
37 	       SAS_ADDR_SIZE);
38 	resp_data[40] = (phy->minimum_linkrate << 4) |
39 		phy->minimum_linkrate_hw;
40 	resp_data[41] = (phy->maximum_linkrate << 4) |
41 		phy->maximum_linkrate_hw;
42 
43 	if (!sas_ha->sas_phy[phy_id]->port ||
44 	    !sas_ha->sas_phy[phy_id]->port->port_dev)
45 		return;
46 
47 	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
48 	resp_data[12] = rphy->identify.device_type << 4;
49 	resp_data[14] = rphy->identify.initiator_port_protocols;
50 	resp_data[15] = rphy->identify.target_port_protocols;
51 }
52 
53 static void sas_report_phy_sata(struct sas_ha_struct *sas_ha, u8 *resp_data,
54 				u8 phy_id)
55 {
56 	struct sas_rphy *rphy;
57 	struct dev_to_host_fis *fis;
58 	int i;
59 
60 	if (phy_id >= sas_ha->num_phys) {
61 		resp_data[2] = SMP_RESP_NO_PHY;
62 		return;
63 	}
64 
65 	resp_data[2] = SMP_RESP_PHY_NO_SATA;
66 
67 	if (!sas_ha->sas_phy[phy_id]->port)
68 		return;
69 
70 	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
71 	fis = (struct dev_to_host_fis *)
72 		sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd;
73 	if (rphy->identify.target_port_protocols != SAS_PROTOCOL_SATA)
74 		return;
75 
76 	resp_data[2] = SMP_RESP_FUNC_ACC;
77 	resp_data[9] = phy_id;
78 	memcpy(resp_data + 16, sas_ha->sas_phy[phy_id]->attached_sas_addr,
79 	       SAS_ADDR_SIZE);
80 
81 	/* check to see if we have a valid d2h fis */
82 	if (fis->fis_type != 0x34)
83 		return;
84 
85 	/* the d2h fis is required by the standard to be in LE format */
86 	for (i = 0; i < 20; i += 4) {
87 		u8 *dst = resp_data + 24 + i, *src =
88 			&sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd[i];
89 		dst[0] = src[3];
90 		dst[1] = src[2];
91 		dst[2] = src[1];
92 		dst[3] = src[0];
93 	}
94 }
95 
96 static void sas_phy_control(struct sas_ha_struct *sas_ha, u8 phy_id,
97 			    u8 phy_op, enum sas_linkrate min,
98 			    enum sas_linkrate max, u8 *resp_data)
99 {
100 	struct sas_internal *i =
101 		to_sas_internal(sas_ha->core.shost->transportt);
102 	struct sas_phy_linkrates rates;
103 
104 	if (phy_id >= sas_ha->num_phys) {
105 		resp_data[2] = SMP_RESP_NO_PHY;
106 		return;
107 	}
108 	switch (phy_op) {
109 	case PHY_FUNC_NOP:
110 	case PHY_FUNC_LINK_RESET:
111 	case PHY_FUNC_HARD_RESET:
112 	case PHY_FUNC_DISABLE:
113 	case PHY_FUNC_CLEAR_ERROR_LOG:
114 	case PHY_FUNC_CLEAR_AFFIL:
115 	case PHY_FUNC_TX_SATA_PS_SIGNAL:
116 		break;
117 
118 	default:
119 		resp_data[2] = SMP_RESP_PHY_UNK_OP;
120 		return;
121 	}
122 
123 	rates.minimum_linkrate = min;
124 	rates.maximum_linkrate = max;
125 
126 	if (i->dft->lldd_control_phy(sas_ha->sas_phy[phy_id], phy_op, &rates))
127 		resp_data[2] = SMP_RESP_FUNC_FAILED;
128 	else
129 		resp_data[2] = SMP_RESP_FUNC_ACC;
130 }
131 
132 int sas_smp_host_handler(struct Scsi_Host *shost, struct request *req,
133 			 struct request *rsp)
134 {
135 	u8 *req_data = NULL, *resp_data = NULL, *buf;
136 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
137 	int error = -EINVAL;
138 
139 	/* eight is the minimum size for request and response frames */
140 	if (blk_rq_bytes(req) < 8 || blk_rq_bytes(rsp) < 8)
141 		goto out;
142 
143 	if (bio_offset(req->bio) + blk_rq_bytes(req) > PAGE_SIZE ||
144 	    bio_offset(rsp->bio) + blk_rq_bytes(rsp) > PAGE_SIZE) {
145 		shost_printk(KERN_ERR, shost,
146 			"SMP request/response frame crosses page boundary");
147 		goto out;
148 	}
149 
150 	req_data = kzalloc(blk_rq_bytes(req), GFP_KERNEL);
151 
152 	/* make sure frame can always be built ... we copy
153 	 * back only the requested length */
154 	resp_data = kzalloc(max(blk_rq_bytes(rsp), 128U), GFP_KERNEL);
155 
156 	if (!req_data || !resp_data) {
157 		error = -ENOMEM;
158 		goto out;
159 	}
160 
161 	local_irq_disable();
162 	buf = kmap_atomic(bio_page(req->bio), KM_USER0) + bio_offset(req->bio);
163 	memcpy(req_data, buf, blk_rq_bytes(req));
164 	kunmap_atomic(buf - bio_offset(req->bio), KM_USER0);
165 	local_irq_enable();
166 
167 	if (req_data[0] != SMP_REQUEST)
168 		goto out;
169 
170 	/* always succeeds ... even if we can't process the request
171 	 * the result is in the response frame */
172 	error = 0;
173 
174 	/* set up default don't know response */
175 	resp_data[0] = SMP_RESPONSE;
176 	resp_data[1] = req_data[1];
177 	resp_data[2] = SMP_RESP_FUNC_UNK;
178 
179 	switch (req_data[1]) {
180 	case SMP_REPORT_GENERAL:
181 		req->resid_len -= 8;
182 		rsp->resid_len -= 32;
183 		resp_data[2] = SMP_RESP_FUNC_ACC;
184 		resp_data[9] = sas_ha->num_phys;
185 		break;
186 
187 	case SMP_REPORT_MANUF_INFO:
188 		req->resid_len -= 8;
189 		rsp->resid_len -= 64;
190 		resp_data[2] = SMP_RESP_FUNC_ACC;
191 		memcpy(resp_data + 12, shost->hostt->name,
192 		       SAS_EXPANDER_VENDOR_ID_LEN);
193 		memcpy(resp_data + 20, "libsas virt phy",
194 		       SAS_EXPANDER_PRODUCT_ID_LEN);
195 		break;
196 
197 	case SMP_READ_GPIO_REG:
198 		/* FIXME: need GPIO support in the transport class */
199 		break;
200 
201 	case SMP_DISCOVER:
202 		req->resid_len -= 16;
203 		if ((int)req->resid_len < 0) {
204 			req->resid_len = 0;
205 			error = -EINVAL;
206 			goto out;
207 		}
208 		rsp->resid_len -= 56;
209 		sas_host_smp_discover(sas_ha, resp_data, req_data[9]);
210 		break;
211 
212 	case SMP_REPORT_PHY_ERR_LOG:
213 		/* FIXME: could implement this with additional
214 		 * libsas callbacks providing the HW supports it */
215 		break;
216 
217 	case SMP_REPORT_PHY_SATA:
218 		req->resid_len -= 16;
219 		if ((int)req->resid_len < 0) {
220 			req->resid_len = 0;
221 			error = -EINVAL;
222 			goto out;
223 		}
224 		rsp->resid_len -= 60;
225 		sas_report_phy_sata(sas_ha, resp_data, req_data[9]);
226 		break;
227 
228 	case SMP_REPORT_ROUTE_INFO:
229 		/* Can't implement; hosts have no routes */
230 		break;
231 
232 	case SMP_WRITE_GPIO_REG:
233 		/* FIXME: need GPIO support in the transport class */
234 		break;
235 
236 	case SMP_CONF_ROUTE_INFO:
237 		/* Can't implement; hosts have no routes */
238 		break;
239 
240 	case SMP_PHY_CONTROL:
241 		req->resid_len -= 44;
242 		if ((int)req->resid_len < 0) {
243 			req->resid_len = 0;
244 			error = -EINVAL;
245 			goto out;
246 		}
247 		rsp->resid_len -= 8;
248 		sas_phy_control(sas_ha, req_data[9], req_data[10],
249 				req_data[32] >> 4, req_data[33] >> 4,
250 				resp_data);
251 		break;
252 
253 	case SMP_PHY_TEST_FUNCTION:
254 		/* FIXME: should this be implemented? */
255 		break;
256 
257 	default:
258 		/* probably a 2.0 function */
259 		break;
260 	}
261 
262 	local_irq_disable();
263 	buf = kmap_atomic(bio_page(rsp->bio), KM_USER0) + bio_offset(rsp->bio);
264 	memcpy(buf, resp_data, blk_rq_bytes(rsp));
265 	flush_kernel_dcache_page(bio_page(rsp->bio));
266 	kunmap_atomic(buf - bio_offset(rsp->bio), KM_USER0);
267 	local_irq_enable();
268 
269  out:
270 	kfree(req_data);
271 	kfree(resp_data);
272 	return error;
273 }
274