diff options
Diffstat (limited to 'drivers/s390/crypto/ap_bus.c')
| -rw-r--r-- | drivers/s390/crypto/ap_bus.c | 174 |
1 files changed, 171 insertions, 3 deletions
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index e3fe6838293..2335be5f9bf 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -5,6 +5,7 @@ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com> * Martin Schwidefsky <schwidefsky@de.ibm.com> * Ralph Wuerthner <rwuerthn@de.ibm.com> + * Felix Beck <felix.beck@de.ibm.com> * * Adjunct processor bus. * @@ -34,6 +35,10 @@ #include <linux/mutex.h> #include <asm/s390_rdev.h> #include <asm/reset.h> +#include <asm/airq.h> +#include <asm/atomic.h> +#include <asm/system.h> +#include <asm/isc.h> #include <linux/hrtimer.h> #include <linux/ktime.h> @@ -46,6 +51,7 @@ static enum hrtimer_restart ap_poll_timeout(struct hrtimer *); static int ap_poll_thread_start(void); static void ap_poll_thread_stop(void); static void ap_request_timeout(unsigned long); +static inline void ap_schedule_poll_timer(void); /* * Module description. @@ -80,19 +86,29 @@ static int ap_config_time = AP_CONFIG_TIME; static DECLARE_WORK(ap_config_work, ap_scan_bus); /* - * Tasklet & timer for AP request polling. + * Tasklet & timer for AP request polling and interrupts */ static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0); static atomic_t ap_poll_requests = ATOMIC_INIT(0); static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait); static struct task_struct *ap_poll_kthread = NULL; static DEFINE_MUTEX(ap_poll_thread_mutex); +static void *ap_interrupt_indicator; static struct hrtimer ap_poll_timer; /* In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds. * If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.*/ static unsigned long long poll_timeout = 250000; /** + * ap_using_interrupts() - Returns non-zero if interrupt support is + * available. + */ +static inline int ap_using_interrupts(void) +{ + return ap_interrupt_indicator != NULL; +} + +/** * ap_intructions_available() - Test if AP instructions are available. * * Returns 0 if the AP instructions are installed. @@ -113,6 +129,23 @@ static inline int ap_instructions_available(void) } /** + * ap_interrupts_available(): Test if AP interrupts are available. + * + * Returns 1 if AP interrupts are available. + */ +static int ap_interrupts_available(void) +{ + unsigned long long facility_bits[2]; + + if (stfle(facility_bits, 2) <= 1) + return 0; + if (!(facility_bits[0] & (1ULL << 61)) || + !(facility_bits[1] & (1ULL << 62))) + return 0; + return 1; +} + +/** * ap_test_queue(): Test adjunct processor queue. * @qid: The AP queue number * @queue_depth: Pointer to queue depth value @@ -152,6 +185,80 @@ static inline struct ap_queue_status ap_reset_queue(ap_qid_t qid) return reg1; } +#ifdef CONFIG_64BIT +/** + * ap_queue_interruption_control(): Enable interruption for a specific AP. + * @qid: The AP queue number + * @ind: The notification indicator byte + * + * Returns AP queue status. + */ +static inline struct ap_queue_status +ap_queue_interruption_control(ap_qid_t qid, void *ind) +{ + register unsigned long reg0 asm ("0") = qid | 0x03000000UL; + register unsigned long reg1_in asm ("1") = 0x0000800000000000UL | AP_ISC; + register struct ap_queue_status reg1_out asm ("1"); + register void *reg2 asm ("2") = ind; + asm volatile( + ".long 0xb2af0000" /* PQAP(RAPQ) */ + : "+d" (reg0), "+d" (reg1_in), "=d" (reg1_out), "+d" (reg2) + : + : "cc" ); + return reg1_out; +} +#endif + +/** + * ap_queue_enable_interruption(): Enable interruption on an AP. + * @qid: The AP queue number + * @ind: the notification indicator byte + * + * Enables interruption on AP queue via ap_queue_interruption_control(). Based + * on the return value it waits a while and tests the AP queue if interrupts + * have been switched on using ap_test_queue(). + */ +static int ap_queue_enable_interruption(ap_qid_t qid, void *ind) +{ +#ifdef CONFIG_64BIT + struct ap_queue_status status; + int t_depth, t_device_type, rc, i; + + rc = -EBUSY; + status = ap_queue_interruption_control(qid, ind); + + for (i = 0; i < AP_MAX_RESET; i++) { + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + if (status.int_enabled) + return 0; + break; + case AP_RESPONSE_RESET_IN_PROGRESS: + case AP_RESPONSE_BUSY: + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + case AP_RESPONSE_INVALID_ADDRESS: + return -ENODEV; + case AP_RESPONSE_OTHERWISE_CHANGED: + if (status.int_enabled) + return 0; + break; + default: + break; + } + if (i < AP_MAX_RESET - 1) { + udelay(5); + status = ap_test_queue(qid, &t_depth, &t_device_type); + } + } + return rc; +#else + return -EINVAL; +#endif +} + /** * __ap_send(): Send message to adjunct processor queue. * @qid: The AP queue number @@ -295,6 +402,11 @@ static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type) case AP_RESPONSE_CHECKSTOPPED: rc = -ENODEV; break; + case AP_RESPONSE_INVALID_ADDRESS: + rc = -ENODEV; + break; + case AP_RESPONSE_OTHERWISE_CHANGED: + break; case AP_RESPONSE_BUSY: break; default: @@ -345,6 +457,15 @@ static int ap_init_queue(ap_qid_t qid) status = ap_test_queue(qid, &dummy, &dummy); } } + if (rc == 0 && ap_using_interrupts()) { + rc = ap_queue_enable_interruption(qid, ap_interrupt_indicator); + /* If interruption mode is supported by the machine, + * but an AP can not be enabled for interruption then + * the AP will be discarded. */ + if (rc) + pr_err("Registering adapter interrupts for " + "AP %d failed\n", AP_QID_DEVICE(qid)); + } return rc; } @@ -599,6 +720,14 @@ static ssize_t ap_config_time_show(struct bus_type *bus, char *buf) return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time); } +static ssize_t ap_interrupts_show(struct bus_type *bus, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", + ap_using_interrupts() ? 1 : 0); +} + +static BUS_ATTR(ap_interrupts, 0444, ap_interrupts_show, NULL); + static ssize_t ap_config_time_store(struct bus_type *bus, const char *buf, size_t count) { @@ -653,7 +782,8 @@ static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf, ktime_t hr_time; /* 120 seconds = maximum poll interval */ - if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 || time > 120000000000) + if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 || + time > 120000000000ULL) return -EINVAL; poll_timeout = time; hr_time = ktime_set(0, poll_timeout); @@ -672,6 +802,7 @@ static struct bus_attribute *const ap_bus_attrs[] = { &bus_attr_ap_domain, &bus_attr_config_time, &bus_attr_poll_thread, + &bus_attr_ap_interrupts, &bus_attr_poll_timeout, NULL, }; @@ -814,6 +945,11 @@ out: return rc; } +static void ap_interrupt_handler(void *unused1, void *unused2) +{ + tasklet_schedule(&ap_tasklet); +} + /** * __ap_scan_bus(): Scan the AP bus. * @dev: Pointer to device @@ -928,6 +1064,8 @@ ap_config_timeout(unsigned long ptr) */ static inline void ap_schedule_poll_timer(void) { + if (ap_using_interrupts()) + return; if (hrtimer_is_queued(&ap_poll_timer)) return; hrtimer_start(&ap_poll_timer, ktime_set(0, poll_timeout), @@ -1207,6 +1345,12 @@ static void ap_poll_all(unsigned long dummy) unsigned long flags; struct ap_device *ap_dev; + /* Reset the indicator if interrupts are used. Thus new interrupts can + * be received. Doing it in the beginning of the tasklet is therefor + * important that no requests on any AP get lost. + */ + if (ap_using_interrupts()) + xchg((u8 *)ap_interrupt_indicator, 0); do { flags = 0; spin_lock(&ap_device_lock); @@ -1268,6 +1412,8 @@ static int ap_poll_thread_start(void) { int rc; + if (ap_using_interrupts()) + return 0; mutex_lock(&ap_poll_thread_mutex); if (!ap_poll_kthread) { ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll"); @@ -1301,8 +1447,12 @@ static void ap_request_timeout(unsigned long data) { struct ap_device *ap_dev = (struct ap_device *) data; - if (ap_dev->reset == AP_RESET_ARMED) + if (ap_dev->reset == AP_RESET_ARMED) { ap_dev->reset = AP_RESET_DO; + + if (ap_using_interrupts()) + tasklet_schedule(&ap_tasklet); + } } static void ap_reset_domain(void) @@ -1345,6 +1495,16 @@ int __init ap_module_init(void) printk(KERN_WARNING "AP instructions not installed.\n"); return -ENODEV; } + if (ap_interrupts_available()) { + isc_register(AP_ISC); + ap_interrupt_indicator = s390_register_adapter_interrupt( + &ap_interrupt_handler, NULL, AP_ISC); + if (IS_ERR(ap_interrupt_indicator)) { + ap_interrupt_indicator = NULL; + isc_unregister(AP_ISC); + } + } + register_reset_call(&ap_reset_call); /* Create /sys/bus/ap. */ @@ -1408,6 +1568,10 @@ out_bus: bus_unregister(&ap_bus_type); out: unregister_reset_call(&ap_reset_call); + if (ap_using_interrupts()) { + s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC); + isc_unregister(AP_ISC); + } return rc; } @@ -1443,6 +1607,10 @@ void ap_module_exit(void) bus_remove_file(&ap_bus_type, ap_bus_attrs[i]); bus_unregister(&ap_bus_type); unregister_reset_call(&ap_reset_call); + if (ap_using_interrupts()) { + s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC); + isc_unregister(AP_ISC); + } } #ifndef CONFIG_ZCRYPT_MONOLITHIC |