![Heiko Carstens](/assets/img/avatar_default.png)
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
902 lines
24 KiB
C
902 lines
24 KiB
C
/*
|
|
* drivers/s390/char/sclp.c
|
|
* core function to access sclp interface
|
|
*
|
|
* S390 version
|
|
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
|
|
* Author(s): Martin Peschke <mpeschke@de.ibm.com>
|
|
* Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/err.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/reboot.h>
|
|
#include <linux/jiffies.h>
|
|
#include <asm/types.h>
|
|
#include <asm/s390_ext.h>
|
|
|
|
#include "sclp.h"
|
|
|
|
#define SCLP_HEADER "sclp: "
|
|
|
|
/* Structure for register_early_external_interrupt. */
|
|
static ext_int_info_t ext_int_info_hwc;
|
|
|
|
/* Lock to protect internal data consistency. */
|
|
static DEFINE_SPINLOCK(sclp_lock);
|
|
|
|
/* Mask of events that we can receive from the sclp interface. */
|
|
static sccb_mask_t sclp_receive_mask;
|
|
|
|
/* Mask of events that we can send to the sclp interface. */
|
|
static sccb_mask_t sclp_send_mask;
|
|
|
|
/* List of registered event listeners and senders. */
|
|
static struct list_head sclp_reg_list;
|
|
|
|
/* List of queued requests. */
|
|
static struct list_head sclp_req_queue;
|
|
|
|
/* Data for read and and init requests. */
|
|
static struct sclp_req sclp_read_req;
|
|
static struct sclp_req sclp_init_req;
|
|
static char sclp_read_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
|
|
static char sclp_init_sccb[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
|
|
|
|
/* Timer for request retries. */
|
|
static struct timer_list sclp_request_timer;
|
|
|
|
/* Internal state: is the driver initialized? */
|
|
static volatile enum sclp_init_state_t {
|
|
sclp_init_state_uninitialized,
|
|
sclp_init_state_initializing,
|
|
sclp_init_state_initialized
|
|
} sclp_init_state = sclp_init_state_uninitialized;
|
|
|
|
/* Internal state: is a request active at the sclp? */
|
|
static volatile enum sclp_running_state_t {
|
|
sclp_running_state_idle,
|
|
sclp_running_state_running
|
|
} sclp_running_state = sclp_running_state_idle;
|
|
|
|
/* Internal state: is a read request pending? */
|
|
static volatile enum sclp_reading_state_t {
|
|
sclp_reading_state_idle,
|
|
sclp_reading_state_reading
|
|
} sclp_reading_state = sclp_reading_state_idle;
|
|
|
|
/* Internal state: is the driver currently serving requests? */
|
|
static volatile enum sclp_activation_state_t {
|
|
sclp_activation_state_active,
|
|
sclp_activation_state_deactivating,
|
|
sclp_activation_state_inactive,
|
|
sclp_activation_state_activating
|
|
} sclp_activation_state = sclp_activation_state_active;
|
|
|
|
/* Internal state: is an init mask request pending? */
|
|
static volatile enum sclp_mask_state_t {
|
|
sclp_mask_state_idle,
|
|
sclp_mask_state_initializing
|
|
} sclp_mask_state = sclp_mask_state_idle;
|
|
|
|
/* Maximum retry counts */
|
|
#define SCLP_INIT_RETRY 3
|
|
#define SCLP_MASK_RETRY 3
|
|
|
|
/* Timeout intervals in seconds.*/
|
|
#define SCLP_BUSY_INTERVAL 10
|
|
#define SCLP_RETRY_INTERVAL 15
|
|
|
|
static void sclp_process_queue(void);
|
|
static int sclp_init_mask(int calculate);
|
|
static int sclp_init(void);
|
|
|
|
/* Perform service call. Return 0 on success, non-zero otherwise. */
|
|
static int
|
|
service_call(sclp_cmdw_t command, void *sccb)
|
|
{
|
|
int cc;
|
|
|
|
asm volatile(
|
|
" .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */
|
|
" ipm %0\n"
|
|
" srl %0,28"
|
|
: "=&d" (cc) : "d" (command), "a" (__pa(sccb))
|
|
: "cc", "memory");
|
|
if (cc == 3)
|
|
return -EIO;
|
|
if (cc == 2)
|
|
return -EBUSY;
|
|
return 0;
|
|
}
|
|
|
|
/* Request timeout handler. Restart the request queue. If DATA is non-zero,
|
|
* force restart of running request. */
|
|
static void
|
|
sclp_request_timeout(unsigned long data)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (data) {
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
sclp_running_state = sclp_running_state_idle;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
}
|
|
sclp_process_queue();
|
|
}
|
|
|
|
/* Set up request retry timer. Called while sclp_lock is locked. */
|
|
static inline void
|
|
__sclp_set_request_timer(unsigned long time, void (*function)(unsigned long),
|
|
unsigned long data)
|
|
{
|
|
del_timer(&sclp_request_timer);
|
|
sclp_request_timer.function = function;
|
|
sclp_request_timer.data = data;
|
|
sclp_request_timer.expires = jiffies + time;
|
|
add_timer(&sclp_request_timer);
|
|
}
|
|
|
|
/* Try to start a request. Return zero if the request was successfully
|
|
* started or if it will be started at a later time. Return non-zero otherwise.
|
|
* Called while sclp_lock is locked. */
|
|
static int
|
|
__sclp_start_request(struct sclp_req *req)
|
|
{
|
|
int rc;
|
|
|
|
if (sclp_running_state != sclp_running_state_idle)
|
|
return 0;
|
|
del_timer(&sclp_request_timer);
|
|
rc = service_call(req->command, req->sccb);
|
|
req->start_count++;
|
|
|
|
if (rc == 0) {
|
|
/* Sucessfully started request */
|
|
req->status = SCLP_REQ_RUNNING;
|
|
sclp_running_state = sclp_running_state_running;
|
|
__sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
|
|
sclp_request_timeout, 1);
|
|
return 0;
|
|
} else if (rc == -EBUSY) {
|
|
/* Try again later */
|
|
__sclp_set_request_timer(SCLP_BUSY_INTERVAL * HZ,
|
|
sclp_request_timeout, 0);
|
|
return 0;
|
|
}
|
|
/* Request failed */
|
|
req->status = SCLP_REQ_FAILED;
|
|
return rc;
|
|
}
|
|
|
|
/* Try to start queued requests. */
|
|
static void
|
|
sclp_process_queue(void)
|
|
{
|
|
struct sclp_req *req;
|
|
int rc;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (sclp_running_state != sclp_running_state_idle) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return;
|
|
}
|
|
del_timer(&sclp_request_timer);
|
|
while (!list_empty(&sclp_req_queue)) {
|
|
req = list_entry(sclp_req_queue.next, struct sclp_req, list);
|
|
rc = __sclp_start_request(req);
|
|
if (rc == 0)
|
|
break;
|
|
/* Request failed. */
|
|
list_del(&req->list);
|
|
if (req->callback) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
req->callback(req, req->callback_data);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
}
|
|
|
|
/* Queue a new request. Return zero on success, non-zero otherwise. */
|
|
int
|
|
sclp_add_request(struct sclp_req *req)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if ((sclp_init_state != sclp_init_state_initialized ||
|
|
sclp_activation_state != sclp_activation_state_active) &&
|
|
req != &sclp_init_req) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EIO;
|
|
}
|
|
req->status = SCLP_REQ_QUEUED;
|
|
req->start_count = 0;
|
|
list_add_tail(&req->list, &sclp_req_queue);
|
|
rc = 0;
|
|
/* Start if request is first in list */
|
|
if (req->list.prev == &sclp_req_queue) {
|
|
rc = __sclp_start_request(req);
|
|
if (rc)
|
|
list_del(&req->list);
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_add_request);
|
|
|
|
/* Dispatch events found in request buffer to registered listeners. Return 0
|
|
* if all events were dispatched, non-zero otherwise. */
|
|
static int
|
|
sclp_dispatch_evbufs(struct sccb_header *sccb)
|
|
{
|
|
unsigned long flags;
|
|
struct evbuf_header *evbuf;
|
|
struct list_head *l;
|
|
struct sclp_register *reg;
|
|
int offset;
|
|
int rc;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
rc = 0;
|
|
for (offset = sizeof(struct sccb_header); offset < sccb->length;
|
|
offset += evbuf->length) {
|
|
/* Search for event handler */
|
|
evbuf = (struct evbuf_header *) ((addr_t) sccb + offset);
|
|
reg = NULL;
|
|
list_for_each(l, &sclp_reg_list) {
|
|
reg = list_entry(l, struct sclp_register, list);
|
|
if (reg->receive_mask & (1 << (32 - evbuf->type)))
|
|
break;
|
|
else
|
|
reg = NULL;
|
|
}
|
|
if (reg && reg->receiver_fn) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
reg->receiver_fn(evbuf);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
} else if (reg == NULL)
|
|
rc = -ENOSYS;
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
/* Read event data request callback. */
|
|
static void
|
|
sclp_read_cb(struct sclp_req *req, void *data)
|
|
{
|
|
unsigned long flags;
|
|
struct sccb_header *sccb;
|
|
|
|
sccb = (struct sccb_header *) req->sccb;
|
|
if (req->status == SCLP_REQ_DONE && (sccb->response_code == 0x20 ||
|
|
sccb->response_code == 0x220))
|
|
sclp_dispatch_evbufs(sccb);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
sclp_reading_state = sclp_reading_state_idle;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
}
|
|
|
|
/* Prepare read event data request. Called while sclp_lock is locked. */
|
|
static inline void
|
|
__sclp_make_read_req(void)
|
|
{
|
|
struct sccb_header *sccb;
|
|
|
|
sccb = (struct sccb_header *) sclp_read_sccb;
|
|
clear_page(sccb);
|
|
memset(&sclp_read_req, 0, sizeof(struct sclp_req));
|
|
sclp_read_req.command = SCLP_CMDW_READDATA;
|
|
sclp_read_req.status = SCLP_REQ_QUEUED;
|
|
sclp_read_req.start_count = 0;
|
|
sclp_read_req.callback = sclp_read_cb;
|
|
sclp_read_req.sccb = sccb;
|
|
sccb->length = PAGE_SIZE;
|
|
sccb->function_code = 0;
|
|
sccb->control_mask[2] = 0x80;
|
|
}
|
|
|
|
/* Search request list for request with matching sccb. Return request if found,
|
|
* NULL otherwise. Called while sclp_lock is locked. */
|
|
static inline struct sclp_req *
|
|
__sclp_find_req(u32 sccb)
|
|
{
|
|
struct list_head *l;
|
|
struct sclp_req *req;
|
|
|
|
list_for_each(l, &sclp_req_queue) {
|
|
req = list_entry(l, struct sclp_req, list);
|
|
if (sccb == (u32) (addr_t) req->sccb)
|
|
return req;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* Handler for external interruption. Perform request post-processing.
|
|
* Prepare read event data request if necessary. Start processing of next
|
|
* request on queue. */
|
|
static void
|
|
sclp_interrupt_handler(__u16 code)
|
|
{
|
|
struct sclp_req *req;
|
|
u32 finished_sccb;
|
|
u32 evbuf_pending;
|
|
|
|
spin_lock(&sclp_lock);
|
|
finished_sccb = S390_lowcore.ext_params & 0xfffffff8;
|
|
evbuf_pending = S390_lowcore.ext_params & 0x3;
|
|
if (finished_sccb) {
|
|
req = __sclp_find_req(finished_sccb);
|
|
if (req) {
|
|
/* Request post-processing */
|
|
list_del(&req->list);
|
|
req->status = SCLP_REQ_DONE;
|
|
if (req->callback) {
|
|
spin_unlock(&sclp_lock);
|
|
req->callback(req, req->callback_data);
|
|
spin_lock(&sclp_lock);
|
|
}
|
|
}
|
|
sclp_running_state = sclp_running_state_idle;
|
|
}
|
|
if (evbuf_pending && sclp_receive_mask != 0 &&
|
|
sclp_reading_state == sclp_reading_state_idle &&
|
|
sclp_activation_state == sclp_activation_state_active ) {
|
|
sclp_reading_state = sclp_reading_state_reading;
|
|
__sclp_make_read_req();
|
|
/* Add request to head of queue */
|
|
list_add(&sclp_read_req.list, &sclp_req_queue);
|
|
}
|
|
spin_unlock(&sclp_lock);
|
|
sclp_process_queue();
|
|
}
|
|
|
|
/* Convert interval in jiffies to TOD ticks. */
|
|
static inline u64
|
|
sclp_tod_from_jiffies(unsigned long jiffies)
|
|
{
|
|
return (u64) (jiffies / HZ) << 32;
|
|
}
|
|
|
|
/* Wait until a currently running request finished. Note: while this function
|
|
* is running, no timers are served on the calling CPU. */
|
|
void
|
|
sclp_sync_wait(void)
|
|
{
|
|
unsigned long flags;
|
|
unsigned long cr0, cr0_sync;
|
|
u64 timeout;
|
|
|
|
/* We'll be disabling timer interrupts, so we need a custom timeout
|
|
* mechanism */
|
|
timeout = 0;
|
|
if (timer_pending(&sclp_request_timer)) {
|
|
/* Get timeout TOD value */
|
|
timeout = get_clock() +
|
|
sclp_tod_from_jiffies(sclp_request_timer.expires -
|
|
jiffies);
|
|
}
|
|
local_irq_save(flags);
|
|
/* Prevent bottom half from executing once we force interrupts open */
|
|
local_bh_disable();
|
|
/* Enable service-signal interruption, disable timer interrupts */
|
|
trace_hardirqs_on();
|
|
__ctl_store(cr0, 0, 0);
|
|
cr0_sync = cr0;
|
|
cr0_sync |= 0x00000200;
|
|
cr0_sync &= 0xFFFFF3AC;
|
|
__ctl_load(cr0_sync, 0, 0);
|
|
__raw_local_irq_stosm(0x01);
|
|
/* Loop until driver state indicates finished request */
|
|
while (sclp_running_state != sclp_running_state_idle) {
|
|
/* Check for expired request timer */
|
|
if (timer_pending(&sclp_request_timer) &&
|
|
get_clock() > timeout &&
|
|
del_timer(&sclp_request_timer))
|
|
sclp_request_timer.function(sclp_request_timer.data);
|
|
barrier();
|
|
cpu_relax();
|
|
}
|
|
local_irq_disable();
|
|
__ctl_load(cr0, 0, 0);
|
|
_local_bh_enable();
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_sync_wait);
|
|
|
|
/* Dispatch changes in send and receive mask to registered listeners. */
|
|
static inline void
|
|
sclp_dispatch_state_change(void)
|
|
{
|
|
struct list_head *l;
|
|
struct sclp_register *reg;
|
|
unsigned long flags;
|
|
sccb_mask_t receive_mask;
|
|
sccb_mask_t send_mask;
|
|
|
|
do {
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
reg = NULL;
|
|
list_for_each(l, &sclp_reg_list) {
|
|
reg = list_entry(l, struct sclp_register, list);
|
|
receive_mask = reg->receive_mask & sclp_receive_mask;
|
|
send_mask = reg->send_mask & sclp_send_mask;
|
|
if (reg->sclp_receive_mask != receive_mask ||
|
|
reg->sclp_send_mask != send_mask) {
|
|
reg->sclp_receive_mask = receive_mask;
|
|
reg->sclp_send_mask = send_mask;
|
|
break;
|
|
} else
|
|
reg = NULL;
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
if (reg && reg->state_change_fn)
|
|
reg->state_change_fn(reg);
|
|
} while (reg);
|
|
}
|
|
|
|
struct sclp_statechangebuf {
|
|
struct evbuf_header header;
|
|
u8 validity_sclp_active_facility_mask : 1;
|
|
u8 validity_sclp_receive_mask : 1;
|
|
u8 validity_sclp_send_mask : 1;
|
|
u8 validity_read_data_function_mask : 1;
|
|
u16 _zeros : 12;
|
|
u16 mask_length;
|
|
u64 sclp_active_facility_mask;
|
|
sccb_mask_t sclp_receive_mask;
|
|
sccb_mask_t sclp_send_mask;
|
|
u32 read_data_function_mask;
|
|
} __attribute__((packed));
|
|
|
|
|
|
/* State change event callback. Inform listeners of changes. */
|
|
static void
|
|
sclp_state_change_cb(struct evbuf_header *evbuf)
|
|
{
|
|
unsigned long flags;
|
|
struct sclp_statechangebuf *scbuf;
|
|
|
|
scbuf = (struct sclp_statechangebuf *) evbuf;
|
|
if (scbuf->mask_length != sizeof(sccb_mask_t))
|
|
return;
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (scbuf->validity_sclp_receive_mask)
|
|
sclp_receive_mask = scbuf->sclp_receive_mask;
|
|
if (scbuf->validity_sclp_send_mask)
|
|
sclp_send_mask = scbuf->sclp_send_mask;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
sclp_dispatch_state_change();
|
|
}
|
|
|
|
static struct sclp_register sclp_state_change_event = {
|
|
.receive_mask = EvTyp_StateChange_Mask,
|
|
.receiver_fn = sclp_state_change_cb
|
|
};
|
|
|
|
/* Calculate receive and send mask of currently registered listeners.
|
|
* Called while sclp_lock is locked. */
|
|
static inline void
|
|
__sclp_get_mask(sccb_mask_t *receive_mask, sccb_mask_t *send_mask)
|
|
{
|
|
struct list_head *l;
|
|
struct sclp_register *t;
|
|
|
|
*receive_mask = 0;
|
|
*send_mask = 0;
|
|
list_for_each(l, &sclp_reg_list) {
|
|
t = list_entry(l, struct sclp_register, list);
|
|
*receive_mask |= t->receive_mask;
|
|
*send_mask |= t->send_mask;
|
|
}
|
|
}
|
|
|
|
/* Register event listener. Return 0 on success, non-zero otherwise. */
|
|
int
|
|
sclp_register(struct sclp_register *reg)
|
|
{
|
|
unsigned long flags;
|
|
sccb_mask_t receive_mask;
|
|
sccb_mask_t send_mask;
|
|
int rc;
|
|
|
|
rc = sclp_init();
|
|
if (rc)
|
|
return rc;
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Check event mask for collisions */
|
|
__sclp_get_mask(&receive_mask, &send_mask);
|
|
if (reg->receive_mask & receive_mask || reg->send_mask & send_mask) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EBUSY;
|
|
}
|
|
/* Trigger initial state change callback */
|
|
reg->sclp_receive_mask = 0;
|
|
reg->sclp_send_mask = 0;
|
|
list_add(®->list, &sclp_reg_list);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
rc = sclp_init_mask(1);
|
|
if (rc) {
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
list_del(®->list);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_register);
|
|
|
|
/* Unregister event listener. */
|
|
void
|
|
sclp_unregister(struct sclp_register *reg)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
list_del(®->list);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
sclp_init_mask(1);
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_unregister);
|
|
|
|
/* Remove event buffers which are marked processed. Return the number of
|
|
* remaining event buffers. */
|
|
int
|
|
sclp_remove_processed(struct sccb_header *sccb)
|
|
{
|
|
struct evbuf_header *evbuf;
|
|
int unprocessed;
|
|
u16 remaining;
|
|
|
|
evbuf = (struct evbuf_header *) (sccb + 1);
|
|
unprocessed = 0;
|
|
remaining = sccb->length - sizeof(struct sccb_header);
|
|
while (remaining > 0) {
|
|
remaining -= evbuf->length;
|
|
if (evbuf->flags & 0x80) {
|
|
sccb->length -= evbuf->length;
|
|
memcpy(evbuf, (void *) ((addr_t) evbuf + evbuf->length),
|
|
remaining);
|
|
} else {
|
|
unprocessed++;
|
|
evbuf = (struct evbuf_header *)
|
|
((addr_t) evbuf + evbuf->length);
|
|
}
|
|
}
|
|
return unprocessed;
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_remove_processed);
|
|
|
|
struct init_sccb {
|
|
struct sccb_header header;
|
|
u16 _reserved;
|
|
u16 mask_length;
|
|
sccb_mask_t receive_mask;
|
|
sccb_mask_t send_mask;
|
|
sccb_mask_t sclp_send_mask;
|
|
sccb_mask_t sclp_receive_mask;
|
|
} __attribute__((packed));
|
|
|
|
/* Prepare init mask request. Called while sclp_lock is locked. */
|
|
static inline void
|
|
__sclp_make_init_req(u32 receive_mask, u32 send_mask)
|
|
{
|
|
struct init_sccb *sccb;
|
|
|
|
sccb = (struct init_sccb *) sclp_init_sccb;
|
|
clear_page(sccb);
|
|
memset(&sclp_init_req, 0, sizeof(struct sclp_req));
|
|
sclp_init_req.command = SCLP_CMDW_WRITEMASK;
|
|
sclp_init_req.status = SCLP_REQ_FILLED;
|
|
sclp_init_req.start_count = 0;
|
|
sclp_init_req.callback = NULL;
|
|
sclp_init_req.callback_data = NULL;
|
|
sclp_init_req.sccb = sccb;
|
|
sccb->header.length = sizeof(struct init_sccb);
|
|
sccb->mask_length = sizeof(sccb_mask_t);
|
|
sccb->receive_mask = receive_mask;
|
|
sccb->send_mask = send_mask;
|
|
sccb->sclp_receive_mask = 0;
|
|
sccb->sclp_send_mask = 0;
|
|
}
|
|
|
|
/* Start init mask request. If calculate is non-zero, calculate the mask as
|
|
* requested by registered listeners. Use zero mask otherwise. Return 0 on
|
|
* success, non-zero otherwise. */
|
|
static int
|
|
sclp_init_mask(int calculate)
|
|
{
|
|
unsigned long flags;
|
|
struct init_sccb *sccb = (struct init_sccb *) sclp_init_sccb;
|
|
sccb_mask_t receive_mask;
|
|
sccb_mask_t send_mask;
|
|
int retry;
|
|
int rc;
|
|
unsigned long wait;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Check if interface is in appropriate state */
|
|
if (sclp_mask_state != sclp_mask_state_idle) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EBUSY;
|
|
}
|
|
if (sclp_activation_state == sclp_activation_state_inactive) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EINVAL;
|
|
}
|
|
sclp_mask_state = sclp_mask_state_initializing;
|
|
/* Determine mask */
|
|
if (calculate)
|
|
__sclp_get_mask(&receive_mask, &send_mask);
|
|
else {
|
|
receive_mask = 0;
|
|
send_mask = 0;
|
|
}
|
|
rc = -EIO;
|
|
for (retry = 0; retry <= SCLP_MASK_RETRY; retry++) {
|
|
/* Prepare request */
|
|
__sclp_make_init_req(receive_mask, send_mask);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
if (sclp_add_request(&sclp_init_req)) {
|
|
/* Try again later */
|
|
wait = jiffies + SCLP_BUSY_INTERVAL * HZ;
|
|
while (time_before(jiffies, wait))
|
|
sclp_sync_wait();
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
continue;
|
|
}
|
|
while (sclp_init_req.status != SCLP_REQ_DONE &&
|
|
sclp_init_req.status != SCLP_REQ_FAILED)
|
|
sclp_sync_wait();
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (sclp_init_req.status == SCLP_REQ_DONE &&
|
|
sccb->header.response_code == 0x20) {
|
|
/* Successful request */
|
|
if (calculate) {
|
|
sclp_receive_mask = sccb->sclp_receive_mask;
|
|
sclp_send_mask = sccb->sclp_send_mask;
|
|
} else {
|
|
sclp_receive_mask = 0;
|
|
sclp_send_mask = 0;
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
sclp_dispatch_state_change();
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
rc = 0;
|
|
break;
|
|
}
|
|
}
|
|
sclp_mask_state = sclp_mask_state_idle;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
/* Deactivate SCLP interface. On success, new requests will be rejected,
|
|
* events will no longer be dispatched. Return 0 on success, non-zero
|
|
* otherwise. */
|
|
int
|
|
sclp_deactivate(void)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Deactivate can only be called when active */
|
|
if (sclp_activation_state != sclp_activation_state_active) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EINVAL;
|
|
}
|
|
sclp_activation_state = sclp_activation_state_deactivating;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
rc = sclp_init_mask(0);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (rc == 0)
|
|
sclp_activation_state = sclp_activation_state_inactive;
|
|
else
|
|
sclp_activation_state = sclp_activation_state_active;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_deactivate);
|
|
|
|
/* Reactivate SCLP interface after sclp_deactivate. On success, new
|
|
* requests will be accepted, events will be dispatched again. Return 0 on
|
|
* success, non-zero otherwise. */
|
|
int
|
|
sclp_reactivate(void)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Reactivate can only be called when inactive */
|
|
if (sclp_activation_state != sclp_activation_state_inactive) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return -EINVAL;
|
|
}
|
|
sclp_activation_state = sclp_activation_state_activating;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
rc = sclp_init_mask(1);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (rc == 0)
|
|
sclp_activation_state = sclp_activation_state_active;
|
|
else
|
|
sclp_activation_state = sclp_activation_state_inactive;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
EXPORT_SYMBOL(sclp_reactivate);
|
|
|
|
/* Handler for external interruption used during initialization. Modify
|
|
* request state to done. */
|
|
static void
|
|
sclp_check_handler(__u16 code)
|
|
{
|
|
u32 finished_sccb;
|
|
|
|
finished_sccb = S390_lowcore.ext_params & 0xfffffff8;
|
|
/* Is this the interrupt we are waiting for? */
|
|
if (finished_sccb == 0)
|
|
return;
|
|
if (finished_sccb != (u32) (addr_t) sclp_init_sccb) {
|
|
printk(KERN_WARNING SCLP_HEADER "unsolicited interrupt "
|
|
"for buffer at 0x%x\n", finished_sccb);
|
|
return;
|
|
}
|
|
spin_lock(&sclp_lock);
|
|
if (sclp_running_state == sclp_running_state_running) {
|
|
sclp_init_req.status = SCLP_REQ_DONE;
|
|
sclp_running_state = sclp_running_state_idle;
|
|
}
|
|
spin_unlock(&sclp_lock);
|
|
}
|
|
|
|
/* Initial init mask request timed out. Modify request state to failed. */
|
|
static void
|
|
sclp_check_timeout(unsigned long data)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (sclp_running_state == sclp_running_state_running) {
|
|
sclp_init_req.status = SCLP_REQ_FAILED;
|
|
sclp_running_state = sclp_running_state_idle;
|
|
}
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
}
|
|
|
|
/* Perform a check of the SCLP interface. Return zero if the interface is
|
|
* available and there are no pending requests from a previous instance.
|
|
* Return non-zero otherwise. */
|
|
static int
|
|
sclp_check_interface(void)
|
|
{
|
|
struct init_sccb *sccb;
|
|
unsigned long flags;
|
|
int retry;
|
|
int rc;
|
|
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Prepare init mask command */
|
|
rc = register_early_external_interrupt(0x2401, sclp_check_handler,
|
|
&ext_int_info_hwc);
|
|
if (rc) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
for (retry = 0; retry <= SCLP_INIT_RETRY; retry++) {
|
|
__sclp_make_init_req(0, 0);
|
|
sccb = (struct init_sccb *) sclp_init_req.sccb;
|
|
rc = service_call(sclp_init_req.command, sccb);
|
|
if (rc == -EIO)
|
|
break;
|
|
sclp_init_req.status = SCLP_REQ_RUNNING;
|
|
sclp_running_state = sclp_running_state_running;
|
|
__sclp_set_request_timer(SCLP_RETRY_INTERVAL * HZ,
|
|
sclp_check_timeout, 0);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
/* Enable service-signal interruption - needs to happen
|
|
* with IRQs enabled. */
|
|
ctl_set_bit(0, 9);
|
|
/* Wait for signal from interrupt or timeout */
|
|
sclp_sync_wait();
|
|
/* Disable service-signal interruption - needs to happen
|
|
* with IRQs enabled. */
|
|
ctl_clear_bit(0,9);
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
del_timer(&sclp_request_timer);
|
|
if (sclp_init_req.status == SCLP_REQ_DONE &&
|
|
sccb->header.response_code == 0x20) {
|
|
rc = 0;
|
|
break;
|
|
} else
|
|
rc = -EBUSY;
|
|
}
|
|
unregister_early_external_interrupt(0x2401, sclp_check_handler,
|
|
&ext_int_info_hwc);
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
|
|
/* Reboot event handler. Reset send and receive mask to prevent pending SCLP
|
|
* events from interfering with rebooted system. */
|
|
static int
|
|
sclp_reboot_event(struct notifier_block *this, unsigned long event, void *ptr)
|
|
{
|
|
sclp_deactivate();
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block sclp_reboot_notifier = {
|
|
.notifier_call = sclp_reboot_event
|
|
};
|
|
|
|
/* Initialize SCLP driver. Return zero if driver is operational, non-zero
|
|
* otherwise. */
|
|
static int
|
|
sclp_init(void)
|
|
{
|
|
unsigned long flags;
|
|
int rc;
|
|
|
|
if (!MACHINE_HAS_SCLP)
|
|
return -ENODEV;
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
/* Check for previous or running initialization */
|
|
if (sclp_init_state != sclp_init_state_uninitialized) {
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return 0;
|
|
}
|
|
sclp_init_state = sclp_init_state_initializing;
|
|
/* Set up variables */
|
|
INIT_LIST_HEAD(&sclp_req_queue);
|
|
INIT_LIST_HEAD(&sclp_reg_list);
|
|
list_add(&sclp_state_change_event.list, &sclp_reg_list);
|
|
init_timer(&sclp_request_timer);
|
|
/* Check interface */
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
rc = sclp_check_interface();
|
|
spin_lock_irqsave(&sclp_lock, flags);
|
|
if (rc) {
|
|
sclp_init_state = sclp_init_state_uninitialized;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
/* Register reboot handler */
|
|
rc = register_reboot_notifier(&sclp_reboot_notifier);
|
|
if (rc) {
|
|
sclp_init_state = sclp_init_state_uninitialized;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
/* Register interrupt handler */
|
|
rc = register_early_external_interrupt(0x2401, sclp_interrupt_handler,
|
|
&ext_int_info_hwc);
|
|
if (rc) {
|
|
unregister_reboot_notifier(&sclp_reboot_notifier);
|
|
sclp_init_state = sclp_init_state_uninitialized;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
return rc;
|
|
}
|
|
sclp_init_state = sclp_init_state_initialized;
|
|
spin_unlock_irqrestore(&sclp_lock, flags);
|
|
/* Enable service-signal external interruption - needs to happen with
|
|
* IRQs enabled. */
|
|
ctl_set_bit(0, 9);
|
|
sclp_init_mask(1);
|
|
return 0;
|
|
}
|