2 * linux/drivers/s390/cio/thinint_qdio.c
4 * Copyright 2000,2009 IBM Corp.
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>
10 #include <linux/slab.h>
11 #include <asm/atomic.h>
12 #include <asm/debug.h>
20 #include "qdio_debug.h"
23 * Restriction: only 63 iqdio subchannels would have its own indicator,
24 * after that, subsequent subchannels share one indicator
26 #define TIQDIO_NR_NONSHARED_IND 63
27 #define TIQDIO_NR_INDICATORS (TIQDIO_NR_NONSHARED_IND + 1)
29 /* list of thin interrupt input queues */
30 static LIST_HEAD(tiq_list
);
31 DEFINE_MUTEX(tiq_list_lock
);
33 /* adapter local summary indicator */
34 static u8
*tiqdio_alsi
;
36 struct indicator_t
*q_indicators
;
38 static int css_qdio_omit_svs
;
40 static u64 last_ai_time
;
42 static inline unsigned long do_clear_global_summary(void)
44 register unsigned long __fn
asm("1") = 3;
45 register unsigned long __tmp
asm("2");
46 register unsigned long __time
asm("3");
49 " .insn rre,0xb2650000,2,0"
50 : "+d" (__fn
), "=d" (__tmp
), "=d" (__time
));
54 /* returns addr for the device state change indicator */
55 static u32
*get_indicator(void)
59 for (i
= 0; i
< TIQDIO_NR_NONSHARED_IND
; i
++)
60 if (!atomic_read(&q_indicators
[i
].count
)) {
61 atomic_set(&q_indicators
[i
].count
, 1);
62 return &q_indicators
[i
].ind
;
65 /* use the shared indicator */
66 atomic_inc(&q_indicators
[TIQDIO_SHARED_IND
].count
);
67 return &q_indicators
[TIQDIO_SHARED_IND
].ind
;
70 static void put_indicator(u32
*addr
)
76 i
= ((unsigned long)addr
- (unsigned long)q_indicators
) /
77 sizeof(struct indicator_t
);
78 atomic_dec(&q_indicators
[i
].count
);
81 void tiqdio_add_input_queues(struct qdio_irq
*irq_ptr
)
86 /* No TDD facility? If we must use SIGA-s we can also omit SVS. */
87 if (!css_qdio_omit_svs
&& irq_ptr
->siga_flag
.sync
)
88 css_qdio_omit_svs
= 1;
90 mutex_lock(&tiq_list_lock
);
91 for_each_input_queue(irq_ptr
, q
, i
)
92 list_add_rcu(&q
->entry
, &tiq_list
);
93 mutex_unlock(&tiq_list_lock
);
94 xchg(irq_ptr
->dsci
, 1 << 7);
97 void tiqdio_remove_input_queues(struct qdio_irq
*irq_ptr
)
102 for (i
= 0; i
< irq_ptr
->nr_input_qs
; i
++) {
103 q
= irq_ptr
->input_qs
[i
];
104 /* if establish triggered an error */
105 if (!q
|| !q
->entry
.prev
|| !q
->entry
.next
)
108 mutex_lock(&tiq_list_lock
);
109 list_del_rcu(&q
->entry
);
110 mutex_unlock(&tiq_list_lock
);
115 static inline int shared_ind_used(void)
117 return atomic_read(&q_indicators
[TIQDIO_SHARED_IND
].count
);
121 * tiqdio_thinint_handler - thin interrupt handler for qdio
122 * @alsi: pointer to adapter local summary indicator
125 static void tiqdio_thinint_handler(void *alsi
, void *data
)
129 last_ai_time
= S390_lowcore
.int_clock
;
132 * SVS only when needed: issue SVS to benefit from iqdio interrupt
133 * avoidance (SVS clears adapter interrupt suppression overwrite).
135 if (!css_qdio_omit_svs
)
136 do_clear_global_summary();
138 /* reset local summary indicator */
139 if (shared_ind_used())
140 xchg(tiqdio_alsi
, 0);
142 /* protect tiq_list entries, only changed in activate or shutdown */
145 /* check for work on all inbound thinint queues */
146 list_for_each_entry_rcu(q
, &tiq_list
, entry
) {
148 /* only process queues from changed sets */
149 if (!*q
->irq_ptr
->dsci
)
152 if (q
->u
.in
.queue_start_poll
) {
153 /* skip if polling is enabled or already in work */
154 if (test_and_set_bit(QDIO_QUEUE_IRQS_DISABLED
,
155 &q
->u
.in
.queue_irq_state
)) {
156 qperf_inc(q
, int_discarded
);
160 /* avoid dsci clear here, done after processing */
161 q
->u
.in
.queue_start_poll(q
->irq_ptr
->cdev
, q
->nr
,
162 q
->irq_ptr
->int_parm
);
164 /* only clear it if the indicator is non-shared */
165 if (!shared_ind(q
->irq_ptr
))
166 xchg(q
->irq_ptr
->dsci
, 0);
168 * Call inbound processing but not directly
169 * since that could starve other thinint queues.
171 tasklet_schedule(&q
->tasklet
);
173 qperf_inc(q
, adapter_int
);
178 * If the shared indicator was used clear it now after all queues
181 if (shared_ind_used()) {
182 xchg(&q_indicators
[TIQDIO_SHARED_IND
].ind
, 0);
186 xchg(&q_indicators
[TIQDIO_SHARED_IND
].ind
, 1 << 7);
190 static int set_subchannel_ind(struct qdio_irq
*irq_ptr
, int reset
)
192 struct scssc_area
*scssc_area
;
195 scssc_area
= (struct scssc_area
*)irq_ptr
->chsc_page
;
196 memset(scssc_area
, 0, PAGE_SIZE
);
199 scssc_area
->summary_indicator_addr
= 0;
200 scssc_area
->subchannel_indicator_addr
= 0;
202 scssc_area
->summary_indicator_addr
= virt_to_phys(tiqdio_alsi
);
203 scssc_area
->subchannel_indicator_addr
=
204 virt_to_phys(irq_ptr
->dsci
);
207 scssc_area
->request
= (struct chsc_header
) {
211 scssc_area
->operation_code
= 0;
212 scssc_area
->ks
= PAGE_DEFAULT_KEY
>> 4;
213 scssc_area
->kc
= PAGE_DEFAULT_KEY
>> 4;
214 scssc_area
->isc
= QDIO_AIRQ_ISC
;
215 scssc_area
->schid
= irq_ptr
->schid
;
217 /* enable the time delay disablement facility */
218 if (css_general_characteristics
.aif_tdd
)
219 scssc_area
->word_with_d_bit
= 0x10000000;
221 rc
= chsc(scssc_area
);
225 rc
= chsc_error_from_response(scssc_area
->response
.code
);
227 DBF_ERROR("%4x SSI r:%4x", irq_ptr
->schid
.sch_no
,
228 scssc_area
->response
.code
);
229 DBF_ERROR_HEX(&scssc_area
->response
, sizeof(void *));
233 DBF_EVENT("setscind");
234 DBF_HEX(&scssc_area
->summary_indicator_addr
, sizeof(unsigned long));
235 DBF_HEX(&scssc_area
->subchannel_indicator_addr
, sizeof(unsigned long));
239 /* allocate non-shared indicators and shared indicator */
240 int __init
tiqdio_allocate_memory(void)
242 q_indicators
= kzalloc(sizeof(struct indicator_t
) * TIQDIO_NR_INDICATORS
,
249 void tiqdio_free_memory(void)
254 int __init
tiqdio_register_thinints(void)
256 isc_register(QDIO_AIRQ_ISC
);
257 tiqdio_alsi
= s390_register_adapter_interrupt(&tiqdio_thinint_handler
,
258 NULL
, QDIO_AIRQ_ISC
);
259 if (IS_ERR(tiqdio_alsi
)) {
260 DBF_EVENT("RTI:%lx", PTR_ERR(tiqdio_alsi
));
262 isc_unregister(QDIO_AIRQ_ISC
);
268 int qdio_establish_thinint(struct qdio_irq
*irq_ptr
)
270 if (!is_thinint_irq(irq_ptr
))
273 /* Check for aif time delay disablement. If installed,
274 * omit SVS even under LPAR
276 if (css_general_characteristics
.aif_tdd
)
277 css_qdio_omit_svs
= 1;
278 return set_subchannel_ind(irq_ptr
, 0);
281 void qdio_setup_thinint(struct qdio_irq
*irq_ptr
)
283 if (!is_thinint_irq(irq_ptr
))
285 irq_ptr
->dsci
= get_indicator();
286 DBF_HEX(&irq_ptr
->dsci
, sizeof(void *));
289 void qdio_shutdown_thinint(struct qdio_irq
*irq_ptr
)
291 if (!is_thinint_irq(irq_ptr
))
294 /* reset adapter interrupt indicators */
295 put_indicator(irq_ptr
->dsci
);
296 set_subchannel_ind(irq_ptr
, 1);
299 void __exit
tiqdio_unregister_thinints(void)
301 WARN_ON(!list_empty(&tiq_list
));
304 s390_unregister_adapter_interrupt(tiqdio_alsi
, QDIO_AIRQ_ISC
);
305 isc_unregister(QDIO_AIRQ_ISC
);