xref: /openbmc/linux/drivers/s390/cio/fcx.c (revision 588b48ca)
1 /*
2  *  Functions for assembling fcx enabled I/O control blocks.
3  *
4  *    Copyright IBM Corp. 2008
5  *    Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/err.h>
13 #include <linux/module.h>
14 #include <asm/fcx.h>
15 #include "cio.h"
16 
17 /**
18  * tcw_get_intrg - return pointer to associated interrogate tcw
19  * @tcw: pointer to the original tcw
20  *
21  * Return a pointer to the interrogate tcw associated with the specified tcw
22  * or %NULL if there is no associated interrogate tcw.
23  */
24 struct tcw *tcw_get_intrg(struct tcw *tcw)
25 {
26 	return (struct tcw *) ((addr_t) tcw->intrg);
27 }
28 EXPORT_SYMBOL(tcw_get_intrg);
29 
30 /**
31  * tcw_get_data - return pointer to input/output data associated with tcw
32  * @tcw: pointer to the tcw
33  *
34  * Return the input or output data address specified in the tcw depending
35  * on whether the r-bit or the w-bit is set. If neither bit is set, return
36  * %NULL.
37  */
38 void *tcw_get_data(struct tcw *tcw)
39 {
40 	if (tcw->r)
41 		return (void *) ((addr_t) tcw->input);
42 	if (tcw->w)
43 		return (void *) ((addr_t) tcw->output);
44 	return NULL;
45 }
46 EXPORT_SYMBOL(tcw_get_data);
47 
48 /**
49  * tcw_get_tccb - return pointer to tccb associated with tcw
50  * @tcw: pointer to the tcw
51  *
52  * Return pointer to the tccb associated with this tcw.
53  */
54 struct tccb *tcw_get_tccb(struct tcw *tcw)
55 {
56 	return (struct tccb *) ((addr_t) tcw->tccb);
57 }
58 EXPORT_SYMBOL(tcw_get_tccb);
59 
60 /**
61  * tcw_get_tsb - return pointer to tsb associated with tcw
62  * @tcw: pointer to the tcw
63  *
64  * Return pointer to the tsb associated with this tcw.
65  */
66 struct tsb *tcw_get_tsb(struct tcw *tcw)
67 {
68 	return (struct tsb *) ((addr_t) tcw->tsb);
69 }
70 EXPORT_SYMBOL(tcw_get_tsb);
71 
72 /**
73  * tcw_init - initialize tcw data structure
74  * @tcw: pointer to the tcw to be initialized
75  * @r: initial value of the r-bit
76  * @w: initial value of the w-bit
77  *
78  * Initialize all fields of the specified tcw data structure with zero and
79  * fill in the format, flags, r and w fields.
80  */
81 void tcw_init(struct tcw *tcw, int r, int w)
82 {
83 	memset(tcw, 0, sizeof(struct tcw));
84 	tcw->format = TCW_FORMAT_DEFAULT;
85 	tcw->flags = TCW_FLAGS_TIDAW_FORMAT(TCW_TIDAW_FORMAT_DEFAULT);
86 	if (r)
87 		tcw->r = 1;
88 	if (w)
89 		tcw->w = 1;
90 }
91 EXPORT_SYMBOL(tcw_init);
92 
93 static inline size_t tca_size(struct tccb *tccb)
94 {
95 	return tccb->tcah.tcal - 12;
96 }
97 
98 static u32 calc_dcw_count(struct tccb *tccb)
99 {
100 	int offset;
101 	struct dcw *dcw;
102 	u32 count = 0;
103 	size_t size;
104 
105 	size = tca_size(tccb);
106 	for (offset = 0; offset < size;) {
107 		dcw = (struct dcw *) &tccb->tca[offset];
108 		count += dcw->count;
109 		if (!(dcw->flags & DCW_FLAGS_CC))
110 			break;
111 		offset += sizeof(struct dcw) + ALIGN((int) dcw->cd_count, 4);
112 	}
113 	return count;
114 }
115 
116 static u32 calc_cbc_size(struct tidaw *tidaw, int num)
117 {
118 	int i;
119 	u32 cbc_data;
120 	u32 cbc_count = 0;
121 	u64 data_count = 0;
122 
123 	for (i = 0; i < num; i++) {
124 		if (tidaw[i].flags & TIDAW_FLAGS_LAST)
125 			break;
126 		/* TODO: find out if padding applies to total of data
127 		 * transferred or data transferred by this tidaw. Assumption:
128 		 * applies to total. */
129 		data_count += tidaw[i].count;
130 		if (tidaw[i].flags & TIDAW_FLAGS_INSERT_CBC) {
131 			cbc_data = 4 + ALIGN(data_count, 4) - data_count;
132 			cbc_count += cbc_data;
133 			data_count += cbc_data;
134 		}
135 	}
136 	return cbc_count;
137 }
138 
139 /**
140  * tcw_finalize - finalize tcw length fields and tidaw list
141  * @tcw: pointer to the tcw
142  * @num_tidaws: the number of tidaws used to address input/output data or zero
143  * if no tida is used
144  *
145  * Calculate the input-/output-count and tccbl field in the tcw, add a
146  * tcat the tccb and terminate the data tidaw list if used.
147  *
148  * Note: in case input- or output-tida is used, the tidaw-list must be stored
149  * in contiguous storage (no ttic). The tcal field in the tccb must be
150  * up-to-date.
151  */
152 void tcw_finalize(struct tcw *tcw, int num_tidaws)
153 {
154 	struct tidaw *tidaw;
155 	struct tccb *tccb;
156 	struct tccb_tcat *tcat;
157 	u32 count;
158 
159 	/* Terminate tidaw list. */
160 	tidaw = tcw_get_data(tcw);
161 	if (num_tidaws > 0)
162 		tidaw[num_tidaws - 1].flags |= TIDAW_FLAGS_LAST;
163 	/* Add tcat to tccb. */
164 	tccb = tcw_get_tccb(tcw);
165 	tcat = (struct tccb_tcat *) &tccb->tca[tca_size(tccb)];
166 	memset(tcat, 0, sizeof(*tcat));
167 	/* Calculate tcw input/output count and tcat transport count. */
168 	count = calc_dcw_count(tccb);
169 	if (tcw->w && (tcw->flags & TCW_FLAGS_OUTPUT_TIDA))
170 		count += calc_cbc_size(tidaw, num_tidaws);
171 	if (tcw->r)
172 		tcw->input_count = count;
173 	else if (tcw->w)
174 		tcw->output_count = count;
175 	tcat->count = ALIGN(count, 4) + 4;
176 	/* Calculate tccbl. */
177 	tcw->tccbl = (sizeof(struct tccb) + tca_size(tccb) +
178 		      sizeof(struct tccb_tcat) - 20) >> 2;
179 }
180 EXPORT_SYMBOL(tcw_finalize);
181 
182 /**
183  * tcw_set_intrg - set the interrogate tcw address of a tcw
184  * @tcw: the tcw address
185  * @intrg_tcw: the address of the interrogate tcw
186  *
187  * Set the address of the interrogate tcw in the specified tcw.
188  */
189 void tcw_set_intrg(struct tcw *tcw, struct tcw *intrg_tcw)
190 {
191 	tcw->intrg = (u32) ((addr_t) intrg_tcw);
192 }
193 EXPORT_SYMBOL(tcw_set_intrg);
194 
195 /**
196  * tcw_set_data - set data address and tida flag of a tcw
197  * @tcw: the tcw address
198  * @data: the data address
199  * @use_tidal: zero of the data address specifies a contiguous block of data,
200  * non-zero if it specifies a list if tidaws.
201  *
202  * Set the input/output data address of a tcw (depending on the value of the
203  * r-flag and w-flag). If @use_tidal is non-zero, the corresponding tida flag
204  * is set as well.
205  */
206 void tcw_set_data(struct tcw *tcw, void *data, int use_tidal)
207 {
208 	if (tcw->r) {
209 		tcw->input = (u64) ((addr_t) data);
210 		if (use_tidal)
211 			tcw->flags |= TCW_FLAGS_INPUT_TIDA;
212 	} else if (tcw->w) {
213 		tcw->output = (u64) ((addr_t) data);
214 		if (use_tidal)
215 			tcw->flags |= TCW_FLAGS_OUTPUT_TIDA;
216 	}
217 }
218 EXPORT_SYMBOL(tcw_set_data);
219 
220 /**
221  * tcw_set_tccb - set tccb address of a tcw
222  * @tcw: the tcw address
223  * @tccb: the tccb address
224  *
225  * Set the address of the tccb in the specified tcw.
226  */
227 void tcw_set_tccb(struct tcw *tcw, struct tccb *tccb)
228 {
229 	tcw->tccb = (u64) ((addr_t) tccb);
230 }
231 EXPORT_SYMBOL(tcw_set_tccb);
232 
233 /**
234  * tcw_set_tsb - set tsb address of a tcw
235  * @tcw: the tcw address
236  * @tsb: the tsb address
237  *
238  * Set the address of the tsb in the specified tcw.
239  */
240 void tcw_set_tsb(struct tcw *tcw, struct tsb *tsb)
241 {
242 	tcw->tsb = (u64) ((addr_t) tsb);
243 }
244 EXPORT_SYMBOL(tcw_set_tsb);
245 
246 /**
247  * tccb_init - initialize tccb
248  * @tccb: the tccb address
249  * @size: the maximum size of the tccb
250  * @sac: the service-action-code to be user
251  *
252  * Initialize the header of the specified tccb by resetting all values to zero
253  * and filling in defaults for format, sac and initial tcal fields.
254  */
255 void tccb_init(struct tccb *tccb, size_t size, u32 sac)
256 {
257 	memset(tccb, 0, size);
258 	tccb->tcah.format = TCCB_FORMAT_DEFAULT;
259 	tccb->tcah.sac = sac;
260 	tccb->tcah.tcal = 12;
261 }
262 EXPORT_SYMBOL(tccb_init);
263 
264 /**
265  * tsb_init - initialize tsb
266  * @tsb: the tsb address
267  *
268  * Initialize the specified tsb by resetting all values to zero.
269  */
270 void tsb_init(struct tsb *tsb)
271 {
272 	memset(tsb, 0, sizeof(*tsb));
273 }
274 EXPORT_SYMBOL(tsb_init);
275 
276 /**
277  * tccb_add_dcw - add a dcw to the tccb
278  * @tccb: the tccb address
279  * @tccb_size: the maximum tccb size
280  * @cmd: the dcw command
281  * @flags: flags for the dcw
282  * @cd: pointer to control data for this dcw or NULL if none is required
283  * @cd_count: number of control data bytes for this dcw
284  * @count: number of data bytes for this dcw
285  *
286  * Add a new dcw to the specified tccb by writing the dcw information specified
287  * by @cmd, @flags, @cd, @cd_count and @count to the tca of the tccb. Return
288  * a pointer to the newly added dcw on success or -%ENOSPC if the new dcw
289  * would exceed the available space as defined by @tccb_size.
290  *
291  * Note: the tcal field of the tccb header will be updates to reflect added
292  * content.
293  */
294 struct dcw *tccb_add_dcw(struct tccb *tccb, size_t tccb_size, u8 cmd, u8 flags,
295 			 void *cd, u8 cd_count, u32 count)
296 {
297 	struct dcw *dcw;
298 	int size;
299 	int tca_offset;
300 
301 	/* Check for space. */
302 	tca_offset = tca_size(tccb);
303 	size = ALIGN(sizeof(struct dcw) + cd_count, 4);
304 	if (sizeof(struct tccb_tcah) + tca_offset + size +
305 	    sizeof(struct tccb_tcat) > tccb_size)
306 		return ERR_PTR(-ENOSPC);
307 	/* Add dcw to tca. */
308 	dcw = (struct dcw *) &tccb->tca[tca_offset];
309 	memset(dcw, 0, size);
310 	dcw->cmd = cmd;
311 	dcw->flags = flags;
312 	dcw->count = count;
313 	dcw->cd_count = cd_count;
314 	if (cd)
315 		memcpy(&dcw->cd[0], cd, cd_count);
316 	tccb->tcah.tcal += size;
317 	return dcw;
318 }
319 EXPORT_SYMBOL(tccb_add_dcw);
320 
321 /**
322  * tcw_add_tidaw - add a tidaw to a tcw
323  * @tcw: the tcw address
324  * @num_tidaws: the current number of tidaws
325  * @flags: flags for the new tidaw
326  * @addr: address value for the new tidaw
327  * @count: count value for the new tidaw
328  *
329  * Add a new tidaw to the input/output data tidaw-list of the specified tcw
330  * (depending on the value of the r-flag and w-flag) and return a pointer to
331  * the new tidaw.
332  *
333  * Note: the tidaw-list is assumed to be contiguous with no ttics. The caller
334  * must ensure that there is enough space for the new tidaw. The last-tidaw
335  * flag for the last tidaw in the list will be set by tcw_finalize.
336  */
337 struct tidaw *tcw_add_tidaw(struct tcw *tcw, int num_tidaws, u8 flags,
338 			    void *addr, u32 count)
339 {
340 	struct tidaw *tidaw;
341 
342 	/* Add tidaw to tidaw-list. */
343 	tidaw = ((struct tidaw *) tcw_get_data(tcw)) + num_tidaws;
344 	memset(tidaw, 0, sizeof(struct tidaw));
345 	tidaw->flags = flags;
346 	tidaw->count = count;
347 	tidaw->addr = (u64) ((addr_t) addr);
348 	return tidaw;
349 }
350 EXPORT_SYMBOL(tcw_add_tidaw);
351