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[S390] stp support. 

Add support for clock synchronization with the server time protocol.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2008-07-14 09:58:56 +02:00 committed by Heiko Carstens
parent 761cdf6aac
commit d2fec59551
5 changed files with 582 additions and 153 deletions
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634
arch/s390/kernel/time.c
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@ -3,7 +3,7 @@
* Time of day based timer functions.
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Copyright IBM Corp. 1999, 2008
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com),
* Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
@ -31,6 +31,7 @@
#include <linux/notifier.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/bootmem.h>
#include <asm/uaccess.h>
#include <asm/delay.h>
#include <asm/s390_ext.h>
@ -162,7 +163,7 @@ void init_cpu_timer(void)
/* Enable clock comparator timer interrupt. */
__ctl_set_bit(0,11);
/* Always allow ETR external interrupts, even without an ETR. */
/* Always allow the timing alert external interrupt. */
__ctl_set_bit(0, 4);
}
@ -170,8 +171,21 @@ static void clock_comparator_interrupt(__u16 code)
{
}
static void etr_timing_alert(struct etr_irq_parm *);
static void stp_timing_alert(struct stp_irq_parm *);
static void timing_alert_interrupt(__u16 code)
{
if (S390_lowcore.ext_params & 0x00c40000)
etr_timing_alert((struct etr_irq_parm *)
&S390_lowcore.ext_params);
if (S390_lowcore.ext_params & 0x00038000)
stp_timing_alert((struct stp_irq_parm *)
&S390_lowcore.ext_params);
}
static void etr_reset(void);
static void etr_ext_handler(__u16);
static void stp_reset(void);
/*
* Get the TOD clock running.
@ -181,6 +195,7 @@ static u64 __init reset_tod_clock(void)
u64 time;
etr_reset();
stp_reset();
if (store_clock(&time) == 0)
return time;
/* TOD clock not running. Set the clock to Unix Epoch. */
@ -231,8 +246,9 @@ void __init time_init(void)
if (clocksource_register(&clocksource_tod) != 0)
panic("Could not register TOD clock source");
/* request the etr external interrupt */
if (register_early_external_interrupt(0x1406, etr_ext_handler,
/* request the timing alert external interrupt */
if (register_early_external_interrupt(0x1406,
timing_alert_interrupt,
&ext_int_etr_cc) != 0)
panic("Couldn't request external interrupt 0x1406");
@ -244,11 +260,113 @@ void __init time_init(void)
#endif
}
/*
* The time is "clock". old is what we think the time is.
* Adjust the value by a multiple of jiffies and add the delta to ntp.
* "delay" is an approximation how long the synchronization took. If
* the time correction is positive, then "delay" is subtracted from
* the time difference and only the remaining part is passed to ntp.
*/
static unsigned long long adjust_time(unsigned long long old,
unsigned long long clock,
unsigned long long delay)
{
unsigned long long delta, ticks;
struct timex adjust;
if (clock > old) {
/* It is later than we thought. */
delta = ticks = clock - old;
delta = ticks = (delta < delay) ? 0 : delta - delay;
delta -= do_div(ticks, CLK_TICKS_PER_JIFFY);
adjust.offset = ticks * (1000000 / HZ);
} else {
/* It is earlier than we thought. */
delta = ticks = old - clock;
delta -= do_div(ticks, CLK_TICKS_PER_JIFFY);
delta = -delta;
adjust.offset = -ticks * (1000000 / HZ);
}
jiffies_timer_cc += delta;
if (adjust.offset != 0) {
printk(KERN_NOTICE "etr: time adjusted by %li micro-seconds\n",
adjust.offset);
adjust.modes = ADJ_OFFSET_SINGLESHOT;
do_adjtimex(&adjust);
}
return delta;
}
static DEFINE_PER_CPU(atomic_t, clock_sync_word);
static unsigned long clock_sync_flags;
#define CLOCK_SYNC_HAS_ETR 0
#define CLOCK_SYNC_HAS_STP 1
#define CLOCK_SYNC_ETR 2
#define CLOCK_SYNC_STP 3
/*
* The synchronous get_clock function. It will write the current clock
* value to the clock pointer and return 0 if the clock is in sync with
* the external time source. If the clock mode is local it will return
* -ENOSYS and -EAGAIN if the clock is not in sync with the external
* reference.
*/
int get_sync_clock(unsigned long long *clock)
{
atomic_t *sw_ptr;
unsigned int sw0, sw1;
sw_ptr = &get_cpu_var(clock_sync_word);
sw0 = atomic_read(sw_ptr);
*clock = get_clock();
sw1 = atomic_read(sw_ptr);
put_cpu_var(clock_sync_sync);
if (sw0 == sw1 && (sw0 & 0x80000000U))
/* Success: time is in sync. */
return 0;
if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags) &&
!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags))
return -ENOSYS;
if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags) &&
!test_bit(CLOCK_SYNC_STP, &clock_sync_flags))
return -EACCES;
return -EAGAIN;
}
EXPORT_SYMBOL(get_sync_clock);
/*
* Make get_sync_clock return -EAGAIN.
*/
static void disable_sync_clock(void *dummy)
{
atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word);
/*
* Clear the in-sync bit 2^31. All get_sync_clock calls will
* fail until the sync bit is turned back on. In addition
* increase the "sequence" counter to avoid the race of an
* etr event and the complete recovery against get_sync_clock.
*/
atomic_clear_mask(0x80000000, sw_ptr);
atomic_inc(sw_ptr);
}
/*
* Make get_sync_clock return 0 again.
* Needs to be called from a context disabled for preemption.
*/
static void enable_sync_clock(void)
{
atomic_t *sw_ptr = &__get_cpu_var(clock_sync_word);
atomic_set_mask(0x80000000, sw_ptr);
}
/*
* External Time Reference (ETR) code.
*/
static int etr_port0_online;
static int etr_port1_online;
static int etr_steai_available;
static int __init early_parse_etr(char *p)
{
@ -273,12 +391,6 @@ enum etr_event {
ETR_EVENT_UPDATE,
};
enum etr_flags {
ETR_FLAG_ENOSYS,
ETR_FLAG_EACCES,
ETR_FLAG_STEAI,
};
/*
* Valid bit combinations of the eacr register are (x = don't care):
* e0 e1 dp p0 p1 ea es sl
@ -305,73 +417,17 @@ enum etr_flags {
*/
static struct etr_eacr etr_eacr;
static u64 etr_tolec; /* time of last eacr update */
static unsigned long etr_flags;
static struct etr_aib etr_port0;
static int etr_port0_uptodate;
static struct etr_aib etr_port1;
static int etr_port1_uptodate;
static unsigned long etr_events;
static struct timer_list etr_timer;
static DEFINE_PER_CPU(atomic_t, etr_sync_word);
static void etr_timeout(unsigned long dummy);
static void etr_work_fn(struct work_struct *work);
static DECLARE_WORK(etr_work, etr_work_fn);
/*
* The etr get_clock function. It will write the current clock value
* to the clock pointer and return 0 if the clock is in sync with the
* external time source. If the clock mode is local it will return
* -ENOSYS and -EAGAIN if the clock is not in sync with the external
* reference. This function is what ETR is all about..
*/
int get_sync_clock(unsigned long long *clock)
{
atomic_t *sw_ptr;
unsigned int sw0, sw1;
sw_ptr = &get_cpu_var(etr_sync_word);
sw0 = atomic_read(sw_ptr);
*clock = get_clock();
sw1 = atomic_read(sw_ptr);
put_cpu_var(etr_sync_sync);
if (sw0 == sw1 && (sw0 & 0x80000000U))
/* Success: time is in sync. */
return 0;
if (test_bit(ETR_FLAG_ENOSYS, &etr_flags))
return -ENOSYS;
if (test_bit(ETR_FLAG_EACCES, &etr_flags))
return -EACCES;
return -EAGAIN;
}
EXPORT_SYMBOL(get_sync_clock);
/*
* Make get_sync_clock return -EAGAIN.
*/
static void etr_disable_sync_clock(void *dummy)
{
atomic_t *sw_ptr = &__get_cpu_var(etr_sync_word);
/*
* Clear the in-sync bit 2^31. All get_sync_clock calls will
* fail until the sync bit is turned back on. In addition
* increase the "sequence" counter to avoid the race of an
* etr event and the complete recovery against get_sync_clock.
*/
atomic_clear_mask(0x80000000, sw_ptr);
atomic_inc(sw_ptr);
}
/*
* Make get_sync_clock return 0 again.
* Needs to be called from a context disabled for preemption.
*/
static void etr_enable_sync_clock(void)
{
atomic_t *sw_ptr = &__get_cpu_var(etr_sync_word);
atomic_set_mask(0x80000000, sw_ptr);
}
/*
* Reset ETR attachment.
*/
@ -381,15 +437,13 @@ static void etr_reset(void)
.e0 = 0, .e1 = 0, ._pad0 = 4, .dp = 0,
.p0 = 0, .p1 = 0, ._pad1 = 0, .ea = 0,
.es = 0, .sl = 0 };
if (etr_setr(&etr_eacr) == 0)
if (etr_setr(&etr_eacr) == 0) {
etr_tolec = get_clock();
else {
set_bit(ETR_FLAG_ENOSYS, &etr_flags);
if (etr_port0_online || etr_port1_online) {
printk(KERN_WARNING "Running on non ETR capable "
"machine, only local mode available.\n");
etr_port0_online = etr_port1_online = 0;
}
set_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags);
} else if (etr_port0_online || etr_port1_online) {
printk(KERN_WARNING "Running on non ETR capable "
"machine, only local mode available.\n");
etr_port0_online = etr_port1_online = 0;
}
}
@ -397,14 +451,12 @@ static int __init etr_init(void)
{
struct etr_aib aib;
if (test_bit(ETR_FLAG_ENOSYS, &etr_flags))
if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags))
return 0;
/* Check if this machine has the steai instruction. */
if (etr_steai(&aib, ETR_STEAI_STEPPING_PORT) == 0)
set_bit(ETR_FLAG_STEAI, &etr_flags);
etr_steai_available = 1;
setup_timer(&etr_timer, etr_timeout, 0UL);
if (!etr_port0_online && !etr_port1_online)
set_bit(ETR_FLAG_EACCES, &etr_flags);
if (etr_port0_online) {
set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events);
schedule_work(&etr_work);
@ -435,7 +487,8 @@ void etr_switch_to_local(void)
{
if (!etr_eacr.sl)
return;
etr_disable_sync_clock(NULL);
if (test_bit(CLOCK_SYNC_ETR, &clock_sync_flags))
disable_sync_clock(NULL);
set_bit(ETR_EVENT_SWITCH_LOCAL, &etr_events);
schedule_work(&etr_work);
}
@ -450,23 +503,21 @@ void etr_sync_check(void)
{
if (!etr_eacr.es)
return;
etr_disable_sync_clock(NULL);
if (test_bit(CLOCK_SYNC_ETR, &clock_sync_flags))
disable_sync_clock(NULL);
set_bit(ETR_EVENT_SYNC_CHECK, &etr_events);
schedule_work(&etr_work);
}
/*
* ETR external interrupt. There are two causes:
* ETR timing alert. There are two causes:
* 1) port state change, check the usability of the port
* 2) port alert, one of the ETR-data-validity bits (v1-v2 bits of the
* sldr-status word) or ETR-data word 1 (edf1) or ETR-data word 3 (edf3)
* or ETR-data word 4 (edf4) has changed.
*/
static void etr_ext_handler(__u16 code)
static void etr_timing_alert(struct etr_irq_parm *intparm)
{
struct etr_interruption_parameter *intparm =
(struct etr_interruption_parameter *) &S390_lowcore.ext_params;
if (intparm->pc0)
/* ETR port 0 state change. */
set_bit(ETR_EVENT_PORT0_CHANGE, &etr_events);
@ -591,58 +642,23 @@ static int etr_aib_follows(struct etr_aib *a1, struct etr_aib *a2, int p)
return 1;
}
/*
* The time is "clock". old is what we think the time is.
* Adjust the value by a multiple of jiffies and add the delta to ntp.
* "delay" is an approximation how long the synchronization took. If
* the time correction is positive, then "delay" is subtracted from
* the time difference and only the remaining part is passed to ntp.
*/
static unsigned long long etr_adjust_time(unsigned long long old,
unsigned long long clock,
unsigned long long delay)
{
unsigned long long delta, ticks;
struct timex adjust;
if (clock > old) {
/* It is later than we thought. */
delta = ticks = clock - old;
delta = ticks = (delta < delay) ? 0 : delta - delay;
delta -= do_div(ticks, CLK_TICKS_PER_JIFFY);
adjust.offset = ticks * (1000000 / HZ);
} else {
/* It is earlier than we thought. */
delta = ticks = old - clock;
delta -= do_div(ticks, CLK_TICKS_PER_JIFFY);
delta = -delta;
adjust.offset = -ticks * (1000000 / HZ);
}
jiffies_timer_cc += delta;
if (adjust.offset != 0) {
printk(KERN_NOTICE "etr: time adjusted by %li micro-seconds\n",
adjust.offset);
adjust.modes = ADJ_OFFSET_SINGLESHOT;
do_adjtimex(&adjust);
}
return delta;
}
static struct {
struct clock_sync_data {
int in_sync;
unsigned long long fixup_cc;
} etr_sync;
};
static void etr_sync_cpu_start(void *dummy)
static void clock_sync_cpu_start(void *dummy)
{
etr_enable_sync_clock();
struct clock_sync_data *sync = dummy;
enable_sync_clock();
/*
* This looks like a busy wait loop but it isn't. etr_sync_cpus
* is called on all other cpus while the TOD clocks is stopped.
* __udelay will stop the cpu on an enabled wait psw until the
* TOD is running again.
*/
while (etr_sync.in_sync == 0) {
while (sync->in_sync == 0) {
__udelay(1);
/*
* A different cpu changes *in_sync. Therefore use
@ -650,17 +666,17 @@ static void etr_sync_cpu_start(void *dummy)
*/
barrier();
}
if (etr_sync.in_sync != 1)
if (sync->in_sync != 1)
/* Didn't work. Clear per-cpu in sync bit again. */
etr_disable_sync_clock(NULL);
disable_sync_clock(NULL);
/*
* This round of TOD syncing is done. Set the clock comparator
* to the next tick and let the processor continue.
*/
fixup_clock_comparator(etr_sync.fixup_cc);
fixup_clock_comparator(sync->fixup_cc);
}
static void etr_sync_cpu_end(void *dummy)
static void clock_sync_cpu_end(void *dummy)
{
}
@ -672,6 +688,7 @@ static void etr_sync_cpu_end(void *dummy)
static int etr_sync_clock(struct etr_aib *aib, int port)
{
struct etr_aib *sync_port;
struct clock_sync_data etr_sync;
unsigned long long clock, old_clock, delay, delta;
int follows;
int rc;
@ -690,9 +707,9 @@ static int etr_sync_clock(struct etr_aib *aib, int port)
*/
memset(&etr_sync, 0, sizeof(etr_sync));
preempt_disable();
smp_call_function(etr_sync_cpu_start, NULL, 0, 0);
smp_call_function(clock_sync_cpu_start, &etr_sync, 0, 0);
local_irq_disable();
etr_enable_sync_clock();
enable_sync_clock();
/* Set clock to next OTE. */
__ctl_set_bit(14, 21);
@ -707,13 +724,13 @@ static int etr_sync_clock(struct etr_aib *aib, int port)
/* Adjust Linux timing variables. */
delay = (unsigned long long)
(aib->edf2.etv - sync_port->edf2.etv) << 32;
delta = etr_adjust_time(old_clock, clock, delay);
delta = adjust_time(old_clock, clock, delay);
etr_sync.fixup_cc = delta;
fixup_clock_comparator(delta);
/* Verify that the clock is properly set. */
if (!etr_aib_follows(sync_port, aib, port)) {
/* Didn't work. */
etr_disable_sync_clock(NULL);
disable_sync_clock(NULL);
etr_sync.in_sync = -EAGAIN;
rc = -EAGAIN;
} else {
@ -724,12 +741,12 @@ static int etr_sync_clock(struct etr_aib *aib, int port)
/* Could not set the clock ?!? */
__ctl_clear_bit(0, 29);
__ctl_clear_bit(14, 21);
etr_disable_sync_clock(NULL);
disable_sync_clock(NULL);
etr_sync.in_sync = -EAGAIN;
rc = -EAGAIN;
}
local_irq_enable();
smp_call_function(etr_sync_cpu_end,NULL,0,0);
smp_call_function(clock_sync_cpu_end, NULL, 0, 0);
preempt_enable();
return rc;
}
@ -832,7 +849,7 @@ static struct etr_eacr etr_handle_update(struct etr_aib *aib,
* Do not try to get the alternate port aib if the clock
* is not in sync yet.
*/
if (!eacr.es)
if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags) && !eacr.es)
return eacr;
/*
@ -840,7 +857,7 @@ static struct etr_eacr etr_handle_update(struct etr_aib *aib,
* the other port immediately. If only stetr is available the
* data-port bit toggle has to be used.
*/
if (test_bit(ETR_FLAG_STEAI, &etr_flags)) {
if (etr_steai_available) {
if (eacr.p0 && !etr_port0_uptodate) {
etr_steai_cv(&etr_port0, ETR_STEAI_PORT_0);
etr_port0_uptodate = 1;
@ -909,10 +926,10 @@ static void etr_work_fn(struct work_struct *work)
if (!eacr.ea) {
/* Both ports offline. Reset everything. */
eacr.dp = eacr.es = eacr.sl = 0;
on_each_cpu(etr_disable_sync_clock, NULL, 0, 1);
on_each_cpu(disable_sync_clock, NULL, 0, 1);
del_timer_sync(&etr_timer);
etr_update_eacr(eacr);
set_bit(ETR_FLAG_EACCES, &etr_flags);
clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags);
return;
}
@ -953,7 +970,6 @@ static void etr_work_fn(struct work_struct *work)
eacr.e1 = 1;
sync_port = (etr_port0_uptodate &&
etr_port_valid(&etr_port0, 0)) ? 0 : -1;
clear_bit(ETR_FLAG_EACCES, &etr_flags);
} else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_pps_mode) {
eacr.sl = 0;
eacr.e0 = 0;
@ -962,7 +978,6 @@ static void etr_work_fn(struct work_struct *work)
eacr.es = 0;
sync_port = (etr_port1_uptodate &&
etr_port_valid(&etr_port1, 1)) ? 1 : -1;
clear_bit(ETR_FLAG_EACCES, &etr_flags);
} else if (eacr.p0 && aib.esw.psc0 == etr_lpsc_operational_step) {
eacr.sl = 1;
eacr.e0 = 1;
@ -976,7 +991,6 @@ static void etr_work_fn(struct work_struct *work)
eacr.e1 = 1;
sync_port = (etr_port0_uptodate &&
etr_port_valid(&etr_port0, 0)) ? 0 : -1;
clear_bit(ETR_FLAG_EACCES, &etr_flags);
} else if (eacr.p1 && aib.esw.psc1 == etr_lpsc_operational_step) {
eacr.sl = 1;
eacr.e0 = 0;
@ -985,19 +999,22 @@ static void etr_work_fn(struct work_struct *work)
eacr.es = 0;
sync_port = (etr_port1_uptodate &&
etr_port_valid(&etr_port1, 1)) ? 1 : -1;
clear_bit(ETR_FLAG_EACCES, &etr_flags);
} else {
/* Both ports not usable. */
eacr.es = eacr.sl = 0;
sync_port = -1;
set_bit(ETR_FLAG_EACCES, &etr_flags);
clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags);
}
if (!test_bit(CLOCK_SYNC_ETR, &clock_sync_flags))
eacr.es = 0;
/*
* If the clock is in sync just update the eacr and return.
* If there is no valid sync port wait for a port update.
*/
if (eacr.es || sync_port < 0) {
if (test_bit(CLOCK_SYNC_STP, &clock_sync_flags) ||
eacr.es || sync_port < 0) {
etr_update_eacr(eacr);
etr_set_tolec_timeout(now);
return;
@ -1018,11 +1035,13 @@ static void etr_work_fn(struct work_struct *work)
* and set up a timer to try again after 0.5 seconds
*/
etr_update_eacr(eacr);
set_bit(CLOCK_SYNC_ETR, &clock_sync_flags);
if (now < etr_tolec + (1600000 << 12) ||
etr_sync_clock(&aib, sync_port) != 0) {
/* Sync failed. Try again in 1/2 second. */
eacr.es = 0;
etr_update_eacr(eacr);
clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags);
etr_set_sync_timeout();
} else
etr_set_tolec_timeout(now);
@ -1097,8 +1116,8 @@ static ssize_t etr_online_store(struct sys_device *dev,
value = simple_strtoul(buf, NULL, 0);
if (value != 0 && value != 1)
return -EINVAL;
if (test_bit(ETR_FLAG_ENOSYS, &etr_flags))
return -ENOSYS;
if (!test_bit(CLOCK_SYNC_HAS_ETR, &clock_sync_flags))
return -EOPNOTSUPP;
if (dev == &etr_port0_dev) {
if (etr_port0_online == value)
return count; /* Nothing to do. */
@ -1292,3 +1311,318 @@ out:
}
device_initcall(etr_init_sysfs);
/*
* Server Time Protocol (STP) code.
*/
static int stp_online;
static struct stp_sstpi stp_info;
static void *stp_page;
static void stp_work_fn(struct work_struct *work);
static DECLARE_WORK(stp_work, stp_work_fn);
static int __init early_parse_stp(char *p)
{
if (strncmp(p, "off", 3) == 0)
stp_online = 0;
else if (strncmp(p, "on", 2) == 0)
stp_online = 1;
return 0;
}
early_param("stp", early_parse_stp);
/*
* Reset STP attachment.
*/
static void stp_reset(void)
{
int rc;
stp_page = alloc_bootmem_pages(PAGE_SIZE);
rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000);
if (rc == 1)
set_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags);
else if (stp_online) {
printk(KERN_WARNING "Running on non STP capable machine.\n");
free_bootmem((unsigned long) stp_page, PAGE_SIZE);
stp_page = NULL;
stp_online = 0;
}
}
static int __init stp_init(void)
{
if (test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags) && stp_online)
schedule_work(&stp_work);
return 0;
}
arch_initcall(stp_init);
/*
* STP timing alert. There are three causes:
* 1) timing status change
* 2) link availability change
* 3) time control parameter change
* In all three cases we are only interested in the clock source state.
* If a STP clock source is now available use it.
*/
static void stp_timing_alert(struct stp_irq_parm *intparm)
{
if (intparm->tsc || intparm->lac || intparm->tcpc)
schedule_work(&stp_work);
}
/*
* STP sync check machine check. This is called when the timing state
* changes from the synchronized state to the unsynchronized state.
* After a STP sync check the clock is not in sync. The machine check
* is broadcasted to all cpus at the same time.
*/
void stp_sync_check(void)
{
if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags))
return;
disable_sync_clock(NULL);
schedule_work(&stp_work);
}
/*
* STP island condition machine check. This is called when an attached
* server attempts to communicate over an STP link and the servers
* have matching CTN ids and have a valid stratum-1 configuration
* but the configurations do not match.
*/
void stp_island_check(void)
{
if (!test_bit(CLOCK_SYNC_STP, &clock_sync_flags))
return;
disable_sync_clock(NULL);
schedule_work(&stp_work);
}
/*
* STP tasklet. Check for the STP state and take over the clock
* synchronization if the STP clock source is usable.
*/
static void stp_work_fn(struct work_struct *work)
{
struct clock_sync_data stp_sync;
unsigned long long old_clock, delta;
int rc;
if (!stp_online) {
chsc_sstpc(stp_page, STP_OP_CTRL, 0x0000);
return;
}
rc = chsc_sstpc(stp_page, STP_OP_CTRL, 0xb0e0);
if (rc)
return;
rc = chsc_sstpi(stp_page, &stp_info, sizeof(struct stp_sstpi));
if (rc || stp_info.c == 0)
return;
/*
* Catch all other cpus and make them wait until we have
* successfully synced the clock. smp_call_function will
* return after all other cpus are in clock_sync_cpu_start.
*/
memset(&stp_sync, 0, sizeof(stp_sync));
preempt_disable();
smp_call_function(clock_sync_cpu_start, &stp_sync, 0, 0);
local_irq_disable();
enable_sync_clock();
set_bit(CLOCK_SYNC_STP, &clock_sync_flags);
if (test_and_clear_bit(CLOCK_SYNC_ETR, &clock_sync_flags))
schedule_work(&etr_work);
rc = 0;
if (stp_info.todoff[0] || stp_info.todoff[1] ||
stp_info.todoff[2] || stp_info.todoff[3] ||
stp_info.tmd != 2) {
old_clock = get_clock();
rc = chsc_sstpc(stp_page, STP_OP_SYNC, 0);
if (rc == 0) {
delta = adjust_time(old_clock, get_clock(), 0);
fixup_clock_comparator(delta);
rc = chsc_sstpi(stp_page, &stp_info,
sizeof(struct stp_sstpi));
if (rc == 0 && stp_info.tmd != 2)
rc = -EAGAIN;
}
}
if (rc) {
disable_sync_clock(NULL);
stp_sync.in_sync = -EAGAIN;
clear_bit(CLOCK_SYNC_STP, &clock_sync_flags);
if (etr_port0_online || etr_port1_online)
schedule_work(&etr_work);
} else
stp_sync.in_sync = 1;
local_irq_enable();
smp_call_function(clock_sync_cpu_end, NULL, 0, 0);
preempt_enable();
}
/*
* STP class sysfs interface functions
*/
static struct sysdev_class stp_sysclass = {
.name = "stp",
};
static ssize_t stp_ctn_id_show(struct sysdev_class *class, char *buf)
{
if (!stp_online)
return -ENODATA;
return sprintf(buf, "%016llx\n",
*(unsigned long long *) stp_info.ctnid);
}
static SYSDEV_CLASS_ATTR(ctn_id, 0400, stp_ctn_id_show, NULL);
static ssize_t stp_ctn_type_show(struct sysdev_class *class, char *buf)
{
if (!stp_online)
return -ENODATA;
return sprintf(buf, "%i\n", stp_info.ctn);
}
static SYSDEV_CLASS_ATTR(ctn_type, 0400, stp_ctn_type_show, NULL);
static ssize_t stp_dst_offset_show(struct sysdev_class *class, char *buf)
{
if (!stp_online || !(stp_info.vbits & 0x2000))
return -ENODATA;
return sprintf(buf, "%i\n", (int)(s16) stp_info.dsto);
}
static SYSDEV_CLASS_ATTR(dst_offset, 0400, stp_dst_offset_show, NULL);
static ssize_t stp_leap_seconds_show(struct sysdev_class *class, char *buf)
{
if (!stp_online || !(stp_info.vbits & 0x8000))
return -ENODATA;
return sprintf(buf, "%i\n", (int)(s16) stp_info.leaps);
}
static SYSDEV_CLASS_ATTR(leap_seconds, 0400, stp_leap_seconds_show, NULL);
static ssize_t stp_stratum_show(struct sysdev_class *class, char *buf)
{
if (!stp_online)
return -ENODATA;
return sprintf(buf, "%i\n", (int)(s16) stp_info.stratum);
}
static SYSDEV_CLASS_ATTR(stratum, 0400, stp_stratum_show, NULL);
static ssize_t stp_time_offset_show(struct sysdev_class *class, char *buf)
{
if (!stp_online || !(stp_info.vbits & 0x0800))
return -ENODATA;
return sprintf(buf, "%i\n", (int) stp_info.tto);
}
static SYSDEV_CLASS_ATTR(time_offset, 0400, stp_time_offset_show, NULL);
static ssize_t stp_time_zone_offset_show(struct sysdev_class *class, char *buf)
{
if (!stp_online || !(stp_info.vbits & 0x4000))
return -ENODATA;
return sprintf(buf, "%i\n", (int)(s16) stp_info.tzo);
}
static SYSDEV_CLASS_ATTR(time_zone_offset, 0400,
stp_time_zone_offset_show, NULL);
static ssize_t stp_timing_mode_show(struct sysdev_class *class, char *buf)
{
if (!stp_online)
return -ENODATA;
return sprintf(buf, "%i\n", stp_info.tmd);
}
static SYSDEV_CLASS_ATTR(timing_mode, 0400, stp_timing_mode_show, NULL);
static ssize_t stp_timing_state_show(struct sysdev_class *class, char *buf)
{
if (!stp_online)
return -ENODATA;
return sprintf(buf, "%i\n", stp_info.tst);
}
static SYSDEV_CLASS_ATTR(timing_state, 0400, stp_timing_state_show, NULL);
static ssize_t stp_online_show(struct sysdev_class *class, char *buf)
{
return sprintf(buf, "%i\n", stp_online);
}
static ssize_t stp_online_store(struct sysdev_class *class,
const char *buf, size_t count)
{
unsigned int value;
value = simple_strtoul(buf, NULL, 0);
if (value != 0 && value != 1)
return -EINVAL;
if (!test_bit(CLOCK_SYNC_HAS_STP, &clock_sync_flags))
return -EOPNOTSUPP;
stp_online = value;
schedule_work(&stp_work);
return count;
}
/*
* Can't use SYSDEV_CLASS_ATTR because the attribute should be named
* stp/online but attr_online already exists in this file ..
*/
static struct sysdev_class_attribute attr_stp_online = {
.attr = { .name = "online", .mode = 0600 },
.show = stp_online_show,
.store = stp_online_store,
};
static struct sysdev_class_attribute *stp_attributes[] = {
&attr_ctn_id,
&attr_ctn_type,
&attr_dst_offset,
&attr_leap_seconds,
&attr_stp_online,
&attr_stratum,
&attr_time_offset,
&attr_time_zone_offset,
&attr_timing_mode,
&attr_timing_state,
NULL
};
static int __init stp_init_sysfs(void)
{
struct sysdev_class_attribute **attr;
int rc;
rc = sysdev_class_register(&stp_sysclass);
if (rc)
goto out;
for (attr = stp_attributes; *attr; attr++) {
rc = sysdev_class_create_file(&stp_sysclass, *attr);
if (rc)
goto out_unreg;
}
return 0;
out_unreg:
for (; attr >= stp_attributes; attr--)
sysdev_class_remove_file(&stp_sysclass, *attr);
sysdev_class_unregister(&stp_sysclass);
out:
return rc;
}
device_initcall(stp_init_sysfs);

49
drivers/s390/cio/chsc.c
View File

@ -874,3 +874,52 @@ exit:
EXPORT_SYMBOL_GPL(css_general_characteristics);
EXPORT_SYMBOL_GPL(css_chsc_characteristics);
int chsc_sstpc(void *page, unsigned int op, u16 ctrl)
{
struct {
struct chsc_header request;
unsigned int rsvd0;
unsigned int op : 8;
unsigned int rsvd1 : 8;
unsigned int ctrl : 16;
unsigned int rsvd2[5];
struct chsc_header response;
unsigned int rsvd3[7];
} __attribute__ ((packed)) *rr;
int rc;
memset(page, 0, PAGE_SIZE);
rr = page;
rr->request.length = 0x0020;
rr->request.code = 0x0033;
rr->op = op;
rr->ctrl = ctrl;
rc = chsc(rr);
if (rc)
return -EIO;
rc = (rr->response.code == 0x0001) ? 0 : -EIO;
return rc;
}
int chsc_sstpi(void *page, void *result, size_t size)
{
struct {
struct chsc_header request;
unsigned int rsvd0[3];
struct chsc_header response;
char data[size];
} __attribute__ ((packed)) *rr;
int rc;
memset(page, 0, PAGE_SIZE);
rr = page;
rr->request.length = 0x0010;
rr->request.code = 0x0038;
rc = chsc(rr);
if (rc)
return -EIO;
memcpy(result, &rr->data, size);
return (rr->response.code == 0x0001) ? 0 : -EIO;
}

4
drivers/s390/s390mach.c
View File

@ -458,6 +458,10 @@ s390_do_machine_check(struct pt_regs *regs)
etr_sync_check();
if (S390_lowcore.external_damage_code & (1U << ED_ETR_SWITCH))
etr_switch_to_local();
if (S390_lowcore.external_damage_code & (1U << ED_STP_SYNC))
stp_sync_check();
if (S390_lowcore.external_damage_code & (1U << ED_STP_ISLAND))
stp_island_check();
}
if (mci->se)

3
drivers/s390/s390mach.h
View File

@ -112,6 +112,9 @@ static inline int stcrw(struct crw *pcrw )
#define ED_ETR_SYNC 12 /* External damage ETR sync check */
#define ED_ETR_SWITCH 13 /* External damage ETR switch to local */
#define ED_STP_SYNC 7 /* External damage STP sync check */
#define ED_STP_ISLAND 6 /* External damage STP island check */
struct pt_regs;
void s390_handle_mcck(void);

45
include/asm-s390/etr.h
View File

@ -122,7 +122,7 @@ struct etr_aib {
} __attribute__ ((packed,aligned(8)));
/* ETR interruption parameter */
struct etr_interruption_parameter {
struct etr_irq_parm {
unsigned int _pad0 : 8;
unsigned int pc0 : 1; /* port 0 state change */
unsigned int pc1 : 1; /* port 1 state change */
@ -213,7 +213,46 @@ static inline int etr_ptff(void *ptff_block, unsigned int func)
#define ETR_PTFF_SGS 0x43 /* set gross steering rate */
/* Functions needed by the machine check handler */
extern void etr_switch_to_local(void);
extern void etr_sync_check(void);
void etr_switch_to_local(void);
void etr_sync_check(void);
/* STP interruption parameter */
struct stp_irq_parm {
unsigned int _pad0 : 14;
unsigned int tsc : 1; /* Timing status change */
unsigned int lac : 1; /* Link availability change */
unsigned int tcpc : 1; /* Time control parameter change */
unsigned int _pad2 : 15;
} __attribute__ ((packed));
#define STP_OP_SYNC 1
#define STP_OP_CTRL 3
struct stp_sstpi {
unsigned int rsvd0;
unsigned int rsvd1 : 8;
unsigned int stratum : 8;
unsigned int vbits : 16;
unsigned int leaps : 16;
unsigned int tmd : 4;
unsigned int ctn : 4;
unsigned int rsvd2 : 3;
unsigned int c : 1;
unsigned int tst : 4;
unsigned int tzo : 16;
unsigned int dsto : 16;
unsigned int ctrl : 16;
unsigned int rsvd3 : 16;
unsigned int tto;
unsigned int rsvd4;
unsigned int ctnid[3];
unsigned int rsvd5;
unsigned int todoff[4];
unsigned int rsvd6[48];
} __attribute__ ((packed));
/* Functions needed by the machine check handler */
void stp_sync_check(void);
void stp_island_check(void);
#endif /* __S390_ETR_H */