Commit | Line | Data |
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779e6e1c JG |
1 | /* |
2 | * linux/drivers/s390/cio/thinint_qdio.c | |
3 | * | |
6486cda6 | 4 | * Copyright 2000,2009 IBM Corp. |
779e6e1c JG |
5 | * Author(s): Utz Bacher <utz.bacher@de.ibm.com> |
6 | * Cornelia Huck <cornelia.huck@de.ibm.com> | |
7 | * Jan Glauber <jang@linux.vnet.ibm.com> | |
8 | */ | |
9 | #include <linux/io.h> | |
5a0e3ad6 | 10 | #include <linux/slab.h> |
779e6e1c JG |
11 | #include <asm/atomic.h> |
12 | #include <asm/debug.h> | |
13 | #include <asm/qdio.h> | |
14 | #include <asm/airq.h> | |
15 | #include <asm/isc.h> | |
16 | ||
17 | #include "cio.h" | |
18 | #include "ioasm.h" | |
19 | #include "qdio.h" | |
20 | #include "qdio_debug.h" | |
779e6e1c JG |
21 | |
22 | /* | |
23 | * Restriction: only 63 iqdio subchannels would have its own indicator, | |
24 | * after that, subsequent subchannels share one indicator | |
25 | */ | |
26 | #define TIQDIO_NR_NONSHARED_IND 63 | |
27 | #define TIQDIO_NR_INDICATORS (TIQDIO_NR_NONSHARED_IND + 1) | |
28 | #define TIQDIO_SHARED_IND 63 | |
29 | ||
30 | /* list of thin interrupt input queues */ | |
31 | static LIST_HEAD(tiq_list); | |
b4547402 | 32 | DEFINE_MUTEX(tiq_list_lock); |
779e6e1c JG |
33 | |
34 | /* adapter local summary indicator */ | |
35 | static unsigned char *tiqdio_alsi; | |
36 | ||
37 | /* device state change indicators */ | |
38 | struct indicator_t { | |
39 | u32 ind; /* u32 because of compare-and-swap performance */ | |
40 | atomic_t count; /* use count, 0 or 1 for non-shared indicators */ | |
41 | }; | |
42 | static struct indicator_t *q_indicators; | |
43 | ||
779e6e1c JG |
44 | static int css_qdio_omit_svs; |
45 | ||
46 | static inline unsigned long do_clear_global_summary(void) | |
47 | { | |
48 | register unsigned long __fn asm("1") = 3; | |
49 | register unsigned long __tmp asm("2"); | |
50 | register unsigned long __time asm("3"); | |
51 | ||
52 | asm volatile( | |
53 | " .insn rre,0xb2650000,2,0" | |
54 | : "+d" (__fn), "=d" (__tmp), "=d" (__time)); | |
55 | return __time; | |
56 | } | |
57 | ||
58 | /* returns addr for the device state change indicator */ | |
59 | static u32 *get_indicator(void) | |
60 | { | |
61 | int i; | |
62 | ||
63 | for (i = 0; i < TIQDIO_NR_NONSHARED_IND; i++) | |
64 | if (!atomic_read(&q_indicators[i].count)) { | |
65 | atomic_set(&q_indicators[i].count, 1); | |
66 | return &q_indicators[i].ind; | |
67 | } | |
68 | ||
69 | /* use the shared indicator */ | |
70 | atomic_inc(&q_indicators[TIQDIO_SHARED_IND].count); | |
71 | return &q_indicators[TIQDIO_SHARED_IND].ind; | |
72 | } | |
73 | ||
74 | static void put_indicator(u32 *addr) | |
75 | { | |
76 | int i; | |
77 | ||
78 | if (!addr) | |
79 | return; | |
80 | i = ((unsigned long)addr - (unsigned long)q_indicators) / | |
81 | sizeof(struct indicator_t); | |
82 | atomic_dec(&q_indicators[i].count); | |
83 | } | |
84 | ||
85 | void tiqdio_add_input_queues(struct qdio_irq *irq_ptr) | |
86 | { | |
87 | struct qdio_q *q; | |
88 | int i; | |
89 | ||
90 | /* No TDD facility? If we must use SIGA-s we can also omit SVS. */ | |
91 | if (!css_qdio_omit_svs && irq_ptr->siga_flag.sync) | |
92 | css_qdio_omit_svs = 1; | |
93 | ||
b4547402 JG |
94 | mutex_lock(&tiq_list_lock); |
95 | for_each_input_queue(irq_ptr, q, i) | |
779e6e1c | 96 | list_add_rcu(&q->entry, &tiq_list); |
b4547402 | 97 | mutex_unlock(&tiq_list_lock); |
779e6e1c | 98 | xchg(irq_ptr->dsci, 1); |
779e6e1c JG |
99 | } |
100 | ||
779e6e1c JG |
101 | void tiqdio_remove_input_queues(struct qdio_irq *irq_ptr) |
102 | { | |
103 | struct qdio_q *q; | |
104 | int i; | |
105 | ||
53b41ba7 JG |
106 | for (i = 0; i < irq_ptr->nr_input_qs; i++) { |
107 | q = irq_ptr->input_qs[i]; | |
108 | /* if establish triggered an error */ | |
109 | if (!q || !q->entry.prev || !q->entry.next) | |
110 | continue; | |
b4547402 JG |
111 | |
112 | mutex_lock(&tiq_list_lock); | |
779e6e1c | 113 | list_del_rcu(&q->entry); |
b4547402 | 114 | mutex_unlock(&tiq_list_lock); |
779e6e1c JG |
115 | synchronize_rcu(); |
116 | } | |
117 | } | |
118 | ||
779e6e1c JG |
119 | static inline int shared_ind(struct qdio_irq *irq_ptr) |
120 | { | |
121 | return irq_ptr->dsci == &q_indicators[TIQDIO_SHARED_IND].ind; | |
122 | } | |
123 | ||
cf9a031c JG |
124 | /** |
125 | * tiqdio_thinint_handler - thin interrupt handler for qdio | |
126 | * @ind: pointer to adapter local summary indicator | |
127 | * @drv_data: NULL | |
128 | */ | |
129 | static void tiqdio_thinint_handler(void *ind, void *drv_data) | |
779e6e1c JG |
130 | { |
131 | struct qdio_q *q; | |
132 | ||
cf9a031c JG |
133 | /* |
134 | * SVS only when needed: issue SVS to benefit from iqdio interrupt | |
135 | * avoidance (SVS clears adapter interrupt suppression overwrite) | |
136 | */ | |
137 | if (!css_qdio_omit_svs) | |
138 | do_clear_global_summary(); | |
139 | ||
140 | /* | |
141 | * reset local summary indicator (tiqdio_alsi) to stop adapter | |
142 | * interrupts for now | |
143 | */ | |
144 | xchg((u8 *)ind, 0); | |
779e6e1c JG |
145 | |
146 | /* protect tiq_list entries, only changed in activate or shutdown */ | |
147 | rcu_read_lock(); | |
148 | ||
cf9a031c | 149 | /* check for work on all inbound thinint queues */ |
779e6e1c JG |
150 | list_for_each_entry_rcu(q, &tiq_list, entry) |
151 | /* only process queues from changed sets */ | |
152 | if (*q->irq_ptr->dsci) { | |
6486cda6 | 153 | qperf_inc(q, adapter_int); |
779e6e1c JG |
154 | |
155 | /* only clear it if the indicator is non-shared */ | |
156 | if (!shared_ind(q->irq_ptr)) | |
157 | xchg(q->irq_ptr->dsci, 0); | |
158 | /* | |
159 | * don't call inbound processing directly since | |
160 | * that could starve other thinint queues | |
161 | */ | |
162 | tasklet_schedule(&q->tasklet); | |
163 | } | |
164 | ||
165 | rcu_read_unlock(); | |
166 | ||
167 | /* | |
168 | * if we used the shared indicator clear it now after all queues | |
169 | * were processed | |
170 | */ | |
171 | if (atomic_read(&q_indicators[TIQDIO_SHARED_IND].count)) { | |
172 | xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 0); | |
173 | ||
174 | /* prevent racing */ | |
175 | if (*tiqdio_alsi) | |
176 | xchg(&q_indicators[TIQDIO_SHARED_IND].ind, 1); | |
177 | } | |
779e6e1c JG |
178 | } |
179 | ||
180 | static int set_subchannel_ind(struct qdio_irq *irq_ptr, int reset) | |
181 | { | |
182 | struct scssc_area *scssc_area; | |
779e6e1c JG |
183 | int rc; |
184 | ||
185 | scssc_area = (struct scssc_area *)irq_ptr->chsc_page; | |
186 | memset(scssc_area, 0, PAGE_SIZE); | |
187 | ||
188 | if (reset) { | |
189 | scssc_area->summary_indicator_addr = 0; | |
190 | scssc_area->subchannel_indicator_addr = 0; | |
191 | } else { | |
192 | scssc_area->summary_indicator_addr = virt_to_phys(tiqdio_alsi); | |
193 | scssc_area->subchannel_indicator_addr = | |
194 | virt_to_phys(irq_ptr->dsci); | |
195 | } | |
196 | ||
197 | scssc_area->request = (struct chsc_header) { | |
198 | .length = 0x0fe0, | |
199 | .code = 0x0021, | |
200 | }; | |
201 | scssc_area->operation_code = 0; | |
d1bf8590 HC |
202 | scssc_area->ks = PAGE_DEFAULT_KEY >> 4; |
203 | scssc_area->kc = PAGE_DEFAULT_KEY >> 4; | |
779e6e1c JG |
204 | scssc_area->isc = QDIO_AIRQ_ISC; |
205 | scssc_area->schid = irq_ptr->schid; | |
206 | ||
207 | /* enable the time delay disablement facility */ | |
208 | if (css_general_characteristics.aif_tdd) | |
209 | scssc_area->word_with_d_bit = 0x10000000; | |
210 | ||
211 | rc = chsc(scssc_area); | |
212 | if (rc) | |
213 | return -EIO; | |
214 | ||
215 | rc = chsc_error_from_response(scssc_area->response.code); | |
216 | if (rc) { | |
22f99347 JG |
217 | DBF_ERROR("%4x SSI r:%4x", irq_ptr->schid.sch_no, |
218 | scssc_area->response.code); | |
219 | DBF_ERROR_HEX(&scssc_area->response, sizeof(void *)); | |
779e6e1c JG |
220 | return rc; |
221 | } | |
222 | ||
22f99347 JG |
223 | DBF_EVENT("setscind"); |
224 | DBF_HEX(&scssc_area->summary_indicator_addr, sizeof(unsigned long)); | |
225 | DBF_HEX(&scssc_area->subchannel_indicator_addr, sizeof(unsigned long)); | |
779e6e1c JG |
226 | return 0; |
227 | } | |
228 | ||
229 | /* allocate non-shared indicators and shared indicator */ | |
230 | int __init tiqdio_allocate_memory(void) | |
231 | { | |
232 | q_indicators = kzalloc(sizeof(struct indicator_t) * TIQDIO_NR_INDICATORS, | |
233 | GFP_KERNEL); | |
234 | if (!q_indicators) | |
235 | return -ENOMEM; | |
236 | return 0; | |
237 | } | |
238 | ||
239 | void tiqdio_free_memory(void) | |
240 | { | |
241 | kfree(q_indicators); | |
242 | } | |
243 | ||
244 | int __init tiqdio_register_thinints(void) | |
245 | { | |
779e6e1c JG |
246 | isc_register(QDIO_AIRQ_ISC); |
247 | tiqdio_alsi = s390_register_adapter_interrupt(&tiqdio_thinint_handler, | |
248 | NULL, QDIO_AIRQ_ISC); | |
249 | if (IS_ERR(tiqdio_alsi)) { | |
22f99347 | 250 | DBF_EVENT("RTI:%lx", PTR_ERR(tiqdio_alsi)); |
779e6e1c JG |
251 | tiqdio_alsi = NULL; |
252 | isc_unregister(QDIO_AIRQ_ISC); | |
253 | return -ENOMEM; | |
254 | } | |
255 | return 0; | |
256 | } | |
257 | ||
258 | int qdio_establish_thinint(struct qdio_irq *irq_ptr) | |
259 | { | |
260 | if (!is_thinint_irq(irq_ptr)) | |
261 | return 0; | |
262 | ||
263 | /* Check for aif time delay disablement. If installed, | |
264 | * omit SVS even under LPAR | |
265 | */ | |
266 | if (css_general_characteristics.aif_tdd) | |
267 | css_qdio_omit_svs = 1; | |
268 | return set_subchannel_ind(irq_ptr, 0); | |
269 | } | |
270 | ||
271 | void qdio_setup_thinint(struct qdio_irq *irq_ptr) | |
272 | { | |
273 | if (!is_thinint_irq(irq_ptr)) | |
274 | return; | |
275 | irq_ptr->dsci = get_indicator(); | |
22f99347 | 276 | DBF_HEX(&irq_ptr->dsci, sizeof(void *)); |
779e6e1c JG |
277 | } |
278 | ||
279 | void qdio_shutdown_thinint(struct qdio_irq *irq_ptr) | |
280 | { | |
281 | if (!is_thinint_irq(irq_ptr)) | |
282 | return; | |
283 | ||
284 | /* reset adapter interrupt indicators */ | |
285 | put_indicator(irq_ptr->dsci); | |
286 | set_subchannel_ind(irq_ptr, 1); | |
287 | } | |
288 | ||
289 | void __exit tiqdio_unregister_thinints(void) | |
290 | { | |
9e890ad8 | 291 | WARN_ON(!list_empty(&tiq_list)); |
779e6e1c JG |
292 | |
293 | if (tiqdio_alsi) { | |
294 | s390_unregister_adapter_interrupt(tiqdio_alsi, QDIO_AIRQ_ISC); | |
295 | isc_unregister(QDIO_AIRQ_ISC); | |
296 | } | |
297 | } |