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 #include <linux/slab.h>
14 #include <linux/export.h>
15 
16 #include "sas_internal.h"
17 
18 #include <scsi/scsi_transport.h>
19 #include <scsi/scsi_transport_sas.h>
20 #include "../scsi_sas_internal.h"
21 
22 static void sas_host_smp_discover(struct sas_ha_struct *sas_ha, u8 *resp_data,
23 				  u8 phy_id)
24 {
25 	struct sas_phy *phy;
26 	struct sas_rphy *rphy;
27 
28 	if (phy_id >= sas_ha->num_phys) {
29 		resp_data[2] = SMP_RESP_NO_PHY;
30 		return;
31 	}
32 	resp_data[2] = SMP_RESP_FUNC_ACC;
33 
34 	phy = sas_ha->sas_phy[phy_id]->phy;
35 	resp_data[9] = phy_id;
36 	resp_data[13] = phy->negotiated_linkrate;
37 	memcpy(resp_data + 16, sas_ha->sas_addr, SAS_ADDR_SIZE);
38 	memcpy(resp_data + 24, sas_ha->sas_phy[phy_id]->attached_sas_addr,
39 	       SAS_ADDR_SIZE);
40 	resp_data[40] = (phy->minimum_linkrate << 4) |
41 		phy->minimum_linkrate_hw;
42 	resp_data[41] = (phy->maximum_linkrate << 4) |
43 		phy->maximum_linkrate_hw;
44 
45 	if (!sas_ha->sas_phy[phy_id]->port ||
46 	    !sas_ha->sas_phy[phy_id]->port->port_dev)
47 		return;
48 
49 	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
50 	resp_data[12] = rphy->identify.device_type << 4;
51 	resp_data[14] = rphy->identify.initiator_port_protocols;
52 	resp_data[15] = rphy->identify.target_port_protocols;
53 }
54 
55 /**
56  * to_sas_gpio_gp_bit - given the gpio frame data find the byte/bit position of 'od'
57  * @od: od bit to find
58  * @data: incoming bitstream (from frame)
59  * @index: requested data register index (from frame)
60  * @count: total number of registers in the bitstream (from frame)
61  * @bit: bit position of 'od' in the returned byte
62  *
63  * returns NULL if 'od' is not in 'data'
64  *
65  * From SFF-8485 v0.7:
66  * "In GPIO_TX[1], bit 0 of byte 3 contains the first bit (i.e., OD0.0)
67  *  and bit 7 of byte 0 contains the 32nd bit (i.e., OD10.1).
68  *
69  *  In GPIO_TX[2], bit 0 of byte 3 contains the 33rd bit (i.e., OD10.2)
70  *  and bit 7 of byte 0 contains the 64th bit (i.e., OD21.0)."
71  *
72  * The general-purpose (raw-bitstream) RX registers have the same layout
73  * although 'od' is renamed 'id' for 'input data'.
74  *
75  * SFF-8489 defines the behavior of the LEDs in response to the 'od' values.
76  */
77 static u8 *to_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count, u8 *bit)
78 {
79 	unsigned int reg;
80 	u8 byte;
81 
82 	/* gp registers start at index 1 */
83 	if (index == 0)
84 		return NULL;
85 
86 	index--; /* make index 0-based */
87 	if (od < index * 32)
88 		return NULL;
89 
90 	od -= index * 32;
91 	reg = od >> 5;
92 
93 	if (reg >= count)
94 		return NULL;
95 
96 	od &= (1 << 5) - 1;
97 	byte = 3 - (od >> 3);
98 	*bit = od & ((1 << 3) - 1);
99 
100 	return &data[reg * 4 + byte];
101 }
102 
103 int try_test_sas_gpio_gp_bit(unsigned int od, u8 *data, u8 index, u8 count)
104 {
105 	u8 *byte;
106 	u8 bit;
107 
108 	byte = to_sas_gpio_gp_bit(od, data, index, count, &bit);
109 	if (!byte)
110 		return -1;
111 
112 	return (*byte >> bit) & 1;
113 }
114 EXPORT_SYMBOL(try_test_sas_gpio_gp_bit);
115 
116 static int sas_host_smp_write_gpio(struct sas_ha_struct *sas_ha, u8 *resp_data,
117 				   u8 reg_type, u8 reg_index, u8 reg_count,
118 				   u8 *req_data)
119 {
120 	struct sas_internal *i = to_sas_internal(sas_ha->core.shost->transportt);
121 	int written;
122 
123 	if (i->dft->lldd_write_gpio == NULL) {
124 		resp_data[2] = SMP_RESP_FUNC_UNK;
125 		return 0;
126 	}
127 
128 	written = i->dft->lldd_write_gpio(sas_ha, reg_type, reg_index,
129 					  reg_count, req_data);
130 
131 	if (written < 0) {
132 		resp_data[2] = SMP_RESP_FUNC_FAILED;
133 		written = 0;
134 	} else
135 		resp_data[2] = SMP_RESP_FUNC_ACC;
136 
137 	return written;
138 }
139 
140 static void sas_report_phy_sata(struct sas_ha_struct *sas_ha, u8 *resp_data,
141 				u8 phy_id)
142 {
143 	struct sas_rphy *rphy;
144 	struct dev_to_host_fis *fis;
145 	int i;
146 
147 	if (phy_id >= sas_ha->num_phys) {
148 		resp_data[2] = SMP_RESP_NO_PHY;
149 		return;
150 	}
151 
152 	resp_data[2] = SMP_RESP_PHY_NO_SATA;
153 
154 	if (!sas_ha->sas_phy[phy_id]->port)
155 		return;
156 
157 	rphy = sas_ha->sas_phy[phy_id]->port->port_dev->rphy;
158 	fis = (struct dev_to_host_fis *)
159 		sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd;
160 	if (rphy->identify.target_port_protocols != SAS_PROTOCOL_SATA)
161 		return;
162 
163 	resp_data[2] = SMP_RESP_FUNC_ACC;
164 	resp_data[9] = phy_id;
165 	memcpy(resp_data + 16, sas_ha->sas_phy[phy_id]->attached_sas_addr,
166 	       SAS_ADDR_SIZE);
167 
168 	/* check to see if we have a valid d2h fis */
169 	if (fis->fis_type != 0x34)
170 		return;
171 
172 	/* the d2h fis is required by the standard to be in LE format */
173 	for (i = 0; i < 20; i += 4) {
174 		u8 *dst = resp_data + 24 + i, *src =
175 			&sas_ha->sas_phy[phy_id]->port->port_dev->frame_rcvd[i];
176 		dst[0] = src[3];
177 		dst[1] = src[2];
178 		dst[2] = src[1];
179 		dst[3] = src[0];
180 	}
181 }
182 
183 static void sas_phy_control(struct sas_ha_struct *sas_ha, u8 phy_id,
184 			    u8 phy_op, enum sas_linkrate min,
185 			    enum sas_linkrate max, u8 *resp_data)
186 {
187 	struct sas_internal *i =
188 		to_sas_internal(sas_ha->core.shost->transportt);
189 	struct sas_phy_linkrates rates;
190 	struct asd_sas_phy *asd_phy;
191 
192 	if (phy_id >= sas_ha->num_phys) {
193 		resp_data[2] = SMP_RESP_NO_PHY;
194 		return;
195 	}
196 
197 	asd_phy = sas_ha->sas_phy[phy_id];
198 	switch (phy_op) {
199 	case PHY_FUNC_NOP:
200 	case PHY_FUNC_LINK_RESET:
201 	case PHY_FUNC_HARD_RESET:
202 	case PHY_FUNC_DISABLE:
203 	case PHY_FUNC_CLEAR_ERROR_LOG:
204 	case PHY_FUNC_CLEAR_AFFIL:
205 	case PHY_FUNC_TX_SATA_PS_SIGNAL:
206 		break;
207 
208 	default:
209 		resp_data[2] = SMP_RESP_PHY_UNK_OP;
210 		return;
211 	}
212 
213 	rates.minimum_linkrate = min;
214 	rates.maximum_linkrate = max;
215 
216 	/* filter reset requests through libata eh */
217 	if (phy_op == PHY_FUNC_LINK_RESET && sas_try_ata_reset(asd_phy) == 0) {
218 		resp_data[2] = SMP_RESP_FUNC_ACC;
219 		return;
220 	}
221 
222 	if (i->dft->lldd_control_phy(asd_phy, phy_op, &rates))
223 		resp_data[2] = SMP_RESP_FUNC_FAILED;
224 	else
225 		resp_data[2] = SMP_RESP_FUNC_ACC;
226 }
227 
228 int sas_smp_host_handler(struct Scsi_Host *shost, struct request *req,
229 			 struct request *rsp)
230 {
231 	u8 *req_data = NULL, *resp_data = NULL, *buf;
232 	struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
233 	int error = -EINVAL;
234 
235 	/* eight is the minimum size for request and response frames */
236 	if (blk_rq_bytes(req) < 8 || blk_rq_bytes(rsp) < 8)
237 		goto out;
238 
239 	if (bio_offset(req->bio) + blk_rq_bytes(req) > PAGE_SIZE ||
240 	    bio_offset(rsp->bio) + blk_rq_bytes(rsp) > PAGE_SIZE) {
241 		shost_printk(KERN_ERR, shost,
242 			"SMP request/response frame crosses page boundary");
243 		goto out;
244 	}
245 
246 	req_data = kzalloc(blk_rq_bytes(req), GFP_KERNEL);
247 
248 	/* make sure frame can always be built ... we copy
249 	 * back only the requested length */
250 	resp_data = kzalloc(max(blk_rq_bytes(rsp), 128U), GFP_KERNEL);
251 
252 	if (!req_data || !resp_data) {
253 		error = -ENOMEM;
254 		goto out;
255 	}
256 
257 	local_irq_disable();
258 	buf = kmap_atomic(bio_page(req->bio));
259 	memcpy(req_data, buf, blk_rq_bytes(req));
260 	kunmap_atomic(buf - bio_offset(req->bio));
261 	local_irq_enable();
262 
263 	if (req_data[0] != SMP_REQUEST)
264 		goto out;
265 
266 	/* always succeeds ... even if we can't process the request
267 	 * the result is in the response frame */
268 	error = 0;
269 
270 	/* set up default don't know response */
271 	resp_data[0] = SMP_RESPONSE;
272 	resp_data[1] = req_data[1];
273 	resp_data[2] = SMP_RESP_FUNC_UNK;
274 
275 	switch (req_data[1]) {
276 	case SMP_REPORT_GENERAL:
277 		req->resid_len -= 8;
278 		rsp->resid_len -= 32;
279 		resp_data[2] = SMP_RESP_FUNC_ACC;
280 		resp_data[9] = sas_ha->num_phys;
281 		break;
282 
283 	case SMP_REPORT_MANUF_INFO:
284 		req->resid_len -= 8;
285 		rsp->resid_len -= 64;
286 		resp_data[2] = SMP_RESP_FUNC_ACC;
287 		memcpy(resp_data + 12, shost->hostt->name,
288 		       SAS_EXPANDER_VENDOR_ID_LEN);
289 		memcpy(resp_data + 20, "libsas virt phy",
290 		       SAS_EXPANDER_PRODUCT_ID_LEN);
291 		break;
292 
293 	case SMP_READ_GPIO_REG:
294 		/* FIXME: need GPIO support in the transport class */
295 		break;
296 
297 	case SMP_DISCOVER:
298 		req->resid_len -= 16;
299 		if ((int)req->resid_len < 0) {
300 			req->resid_len = 0;
301 			error = -EINVAL;
302 			goto out;
303 		}
304 		rsp->resid_len -= 56;
305 		sas_host_smp_discover(sas_ha, resp_data, req_data[9]);
306 		break;
307 
308 	case SMP_REPORT_PHY_ERR_LOG:
309 		/* FIXME: could implement this with additional
310 		 * libsas callbacks providing the HW supports it */
311 		break;
312 
313 	case SMP_REPORT_PHY_SATA:
314 		req->resid_len -= 16;
315 		if ((int)req->resid_len < 0) {
316 			req->resid_len = 0;
317 			error = -EINVAL;
318 			goto out;
319 		}
320 		rsp->resid_len -= 60;
321 		sas_report_phy_sata(sas_ha, resp_data, req_data[9]);
322 		break;
323 
324 	case SMP_REPORT_ROUTE_INFO:
325 		/* Can't implement; hosts have no routes */
326 		break;
327 
328 	case SMP_WRITE_GPIO_REG: {
329 		/* SFF-8485 v0.7 */
330 		const int base_frame_size = 11;
331 		int to_write = req_data[4];
332 
333 		if (blk_rq_bytes(req) < base_frame_size + to_write * 4 ||
334 		    req->resid_len < base_frame_size + to_write * 4) {
335 			resp_data[2] = SMP_RESP_INV_FRM_LEN;
336 			break;
337 		}
338 
339 		to_write = sas_host_smp_write_gpio(sas_ha, resp_data, req_data[2],
340 						   req_data[3], to_write, &req_data[8]);
341 		req->resid_len -= base_frame_size + to_write * 4;
342 		rsp->resid_len -= 8;
343 		break;
344 	}
345 
346 	case SMP_CONF_ROUTE_INFO:
347 		/* Can't implement; hosts have no routes */
348 		break;
349 
350 	case SMP_PHY_CONTROL:
351 		req->resid_len -= 44;
352 		if ((int)req->resid_len < 0) {
353 			req->resid_len = 0;
354 			error = -EINVAL;
355 			goto out;
356 		}
357 		rsp->resid_len -= 8;
358 		sas_phy_control(sas_ha, req_data[9], req_data[10],
359 				req_data[32] >> 4, req_data[33] >> 4,
360 				resp_data);
361 		break;
362 
363 	case SMP_PHY_TEST_FUNCTION:
364 		/* FIXME: should this be implemented? */
365 		break;
366 
367 	default:
368 		/* probably a 2.0 function */
369 		break;
370 	}
371 
372 	local_irq_disable();
373 	buf = kmap_atomic(bio_page(rsp->bio));
374 	memcpy(buf, resp_data, blk_rq_bytes(rsp));
375 	flush_kernel_dcache_page(bio_page(rsp->bio));
376 	kunmap_atomic(buf - bio_offset(rsp->bio));
377 	local_irq_enable();
378 
379  out:
380 	kfree(req_data);
381 	kfree(resp_data);
382 	return error;
383 }
384