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authorMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-23 07:59:19 -0300
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-23 07:59:19 -0300
commitc278256d05a2fc75b427fa6a5dc0024faa93465d (patch)
tree2c09c6c65a4b6c597a568ec2425adb75eff7d5d5 /arch/arc/include/asm/spinlock.h
parent7e5b7d1b3a8facd4dc1ddb5d9ec53c0687d13de7 (diff)
parent009a620848218d521f008141c62f56bf19294dd9 (diff)
Merge branch 'patchwork' into topic/docs-next
* patchwork: (1492 commits) [media] cec: always check all_device_types and features [media] cec: poll should check if there is room in the tx queue [media] vivid: support monitor all mode [media] cec: fix test for unconfigured adapter in main message loop [media] cec: limit the size of the transmit queue [media] cec: zero unused msg part after msg->len [media] cec: don't set fh to NULL in CEC_TRANSMIT [media] cec: clear all status fields before transmit and always fill in sequence [media] cec: CEC_RECEIVE overwrote the timeout field [media] cxd2841er: Reading SNR for DVB-C added [media] cxd2841er: Reading BER and UCB for DVB-C added [media] cxd2841er: fix switch-case for DVB-C [media] cxd2841er: fix signal strength scale for ISDB-T [media] cxd2841er: adjust the dB scale for DVB-C [media] cxd2841er: provide signal strength for DVB-C [media] cxd2841er: fix BER report via DVBv5 stats API [media] mb86a20s: apply mask to val after checking for read failure [media] airspy: fix error logic during device register [media] s5p-cec/TODO: add TODO item [media] cec/TODO: drop comment about sphinx documentation ... Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'arch/arc/include/asm/spinlock.h')
-rw-r--r--arch/arc/include/asm/spinlock.h292
1 files changed, 0 insertions, 292 deletions
diff --git a/arch/arc/include/asm/spinlock.h b/arch/arc/include/asm/spinlock.h
index 800e7c430ca5..cded4a9b5438 100644
--- a/arch/arc/include/asm/spinlock.h
+++ b/arch/arc/include/asm/spinlock.h
@@ -20,11 +20,6 @@
#ifdef CONFIG_ARC_HAS_LLSC
-/*
- * A normal LLOCK/SCOND based system, w/o need for livelock workaround
- */
-#ifndef CONFIG_ARC_STAR_9000923308
-
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
unsigned int val;
@@ -238,293 +233,6 @@ static inline void arch_write_unlock(arch_rwlock_t *rw)
smp_mb();
}
-#else /* CONFIG_ARC_STAR_9000923308 */
-
-/*
- * HS38x4 could get into a LLOCK/SCOND livelock in case of multiple overlapping
- * coherency transactions in the SCU. The exclusive line state keeps rotating
- * among contenting cores leading to a never ending cycle. So break the cycle
- * by deferring the retry of failed exclusive access (SCOND). The actual delay
- * needed is function of number of contending cores as well as the unrelated
- * coherency traffic from other cores. To keep the code simple, start off with
- * small delay of 1 which would suffice most cases and in case of contention
- * double the delay. Eventually the delay is sufficient such that the coherency
- * pipeline is drained, thus a subsequent exclusive access would succeed.
- */
-
-#define SCOND_FAIL_RETRY_VAR_DEF \
- unsigned int delay, tmp; \
-
-#define SCOND_FAIL_RETRY_ASM \
- " ; --- scond fail delay --- \n" \
- " mov %[tmp], %[delay] \n" /* tmp = delay */ \
- "2: brne.d %[tmp], 0, 2b \n" /* while (tmp != 0) */ \
- " sub %[tmp], %[tmp], 1 \n" /* tmp-- */ \
- " rol %[delay], %[delay] \n" /* delay *= 2 */ \
- " b 1b \n" /* start over */ \
- " \n" \
- "4: ; --- done --- \n" \
-
-#define SCOND_FAIL_RETRY_VARS \
- ,[delay] "=&r" (delay), [tmp] "=&r" (tmp) \
-
-static inline void arch_spin_lock(arch_spinlock_t *lock)
-{
- unsigned int val;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[slock]] \n"
- " breq %[val], %[LOCKED], 0b \n" /* spin while LOCKED */
- " scond %[LOCKED], [%[slock]] \n" /* acquire */
- " bz 4f \n" /* done */
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val)
- SCOND_FAIL_RETRY_VARS
- : [slock] "r" (&(lock->slock)),
- [LOCKED] "r" (__ARCH_SPIN_LOCK_LOCKED__)
- : "memory", "cc");
-
- smp_mb();
-}
-
-/* 1 - lock taken successfully */
-static inline int arch_spin_trylock(arch_spinlock_t *lock)
-{
- unsigned int val, got_it = 0;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[slock]] \n"
- " breq %[val], %[LOCKED], 4f \n" /* already LOCKED, just bail */
- " scond %[LOCKED], [%[slock]] \n" /* acquire */
- " bz.d 4f \n"
- " mov.z %[got_it], 1 \n" /* got it */
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val),
- [got_it] "+&r" (got_it)
- SCOND_FAIL_RETRY_VARS
- : [slock] "r" (&(lock->slock)),
- [LOCKED] "r" (__ARCH_SPIN_LOCK_LOCKED__)
- : "memory", "cc");
-
- smp_mb();
-
- return got_it;
-}
-
-static inline void arch_spin_unlock(arch_spinlock_t *lock)
-{
- smp_mb();
-
- lock->slock = __ARCH_SPIN_LOCK_UNLOCKED__;
-
- smp_mb();
-}
-
-/*
- * Read-write spinlocks, allowing multiple readers but only one writer.
- * Unfair locking as Writers could be starved indefinitely by Reader(s)
- */
-
-static inline void arch_read_lock(arch_rwlock_t *rw)
-{
- unsigned int val;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- /*
- * zero means writer holds the lock exclusively, deny Reader.
- * Otherwise grant lock to first/subseq reader
- *
- * if (rw->counter > 0) {
- * rw->counter--;
- * ret = 1;
- * }
- */
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[rwlock]] \n"
- " brls %[val], %[WR_LOCKED], 0b\n" /* <= 0: spin while write locked */
- " sub %[val], %[val], 1 \n" /* reader lock */
- " scond %[val], [%[rwlock]] \n"
- " bz 4f \n" /* done */
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val)
- SCOND_FAIL_RETRY_VARS
- : [rwlock] "r" (&(rw->counter)),
- [WR_LOCKED] "ir" (0)
- : "memory", "cc");
-
- smp_mb();
-}
-
-/* 1 - lock taken successfully */
-static inline int arch_read_trylock(arch_rwlock_t *rw)
-{
- unsigned int val, got_it = 0;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[rwlock]] \n"
- " brls %[val], %[WR_LOCKED], 4f\n" /* <= 0: already write locked, bail */
- " sub %[val], %[val], 1 \n" /* counter-- */
- " scond %[val], [%[rwlock]] \n"
- " bz.d 4f \n"
- " mov.z %[got_it], 1 \n" /* got it */
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val),
- [got_it] "+&r" (got_it)
- SCOND_FAIL_RETRY_VARS
- : [rwlock] "r" (&(rw->counter)),
- [WR_LOCKED] "ir" (0)
- : "memory", "cc");
-
- smp_mb();
-
- return got_it;
-}
-
-static inline void arch_write_lock(arch_rwlock_t *rw)
-{
- unsigned int val;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- /*
- * If reader(s) hold lock (lock < __ARCH_RW_LOCK_UNLOCKED__),
- * deny writer. Otherwise if unlocked grant to writer
- * Hence the claim that Linux rwlocks are unfair to writers.
- * (can be starved for an indefinite time by readers).
- *
- * if (rw->counter == __ARCH_RW_LOCK_UNLOCKED__) {
- * rw->counter = 0;
- * ret = 1;
- * }
- */
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[rwlock]] \n"
- " brne %[val], %[UNLOCKED], 0b \n" /* while !UNLOCKED spin */
- " mov %[val], %[WR_LOCKED] \n"
- " scond %[val], [%[rwlock]] \n"
- " bz 4f \n"
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val)
- SCOND_FAIL_RETRY_VARS
- : [rwlock] "r" (&(rw->counter)),
- [UNLOCKED] "ir" (__ARCH_RW_LOCK_UNLOCKED__),
- [WR_LOCKED] "ir" (0)
- : "memory", "cc");
-
- smp_mb();
-}
-
-/* 1 - lock taken successfully */
-static inline int arch_write_trylock(arch_rwlock_t *rw)
-{
- unsigned int val, got_it = 0;
- SCOND_FAIL_RETRY_VAR_DEF;
-
- smp_mb();
-
- __asm__ __volatile__(
- "0: mov %[delay], 1 \n"
- "1: llock %[val], [%[rwlock]] \n"
- " brne %[val], %[UNLOCKED], 4f \n" /* !UNLOCKED, bail */
- " mov %[val], %[WR_LOCKED] \n"
- " scond %[val], [%[rwlock]] \n"
- " bz.d 4f \n"
- " mov.z %[got_it], 1 \n" /* got it */
- " \n"
- SCOND_FAIL_RETRY_ASM
-
- : [val] "=&r" (val),
- [got_it] "+&r" (got_it)
- SCOND_FAIL_RETRY_VARS
- : [rwlock] "r" (&(rw->counter)),
- [UNLOCKED] "ir" (__ARCH_RW_LOCK_UNLOCKED__),
- [WR_LOCKED] "ir" (0)
- : "memory", "cc");
-
- smp_mb();
-
- return got_it;
-}
-
-static inline void arch_read_unlock(arch_rwlock_t *rw)
-{
- unsigned int val;
-
- smp_mb();
-
- /*
- * rw->counter++;
- */
- __asm__ __volatile__(
- "1: llock %[val], [%[rwlock]] \n"
- " add %[val], %[val], 1 \n"
- " scond %[val], [%[rwlock]] \n"
- " bnz 1b \n"
- " \n"
- : [val] "=&r" (val)
- : [rwlock] "r" (&(rw->counter))
- : "memory", "cc");
-
- smp_mb();
-}
-
-static inline void arch_write_unlock(arch_rwlock_t *rw)
-{
- unsigned int val;
-
- smp_mb();
-
- /*
- * rw->counter = __ARCH_RW_LOCK_UNLOCKED__;
- */
- __asm__ __volatile__(
- "1: llock %[val], [%[rwlock]] \n"
- " scond %[UNLOCKED], [%[rwlock]]\n"
- " bnz 1b \n"
- " \n"
- : [val] "=&r" (val)
- : [rwlock] "r" (&(rw->counter)),
- [UNLOCKED] "r" (__ARCH_RW_LOCK_UNLOCKED__)
- : "memory", "cc");
-
- smp_mb();
-}
-
-#undef SCOND_FAIL_RETRY_VAR_DEF
-#undef SCOND_FAIL_RETRY_ASM
-#undef SCOND_FAIL_RETRY_VARS
-
-#endif /* CONFIG_ARC_STAR_9000923308 */
-
#else /* !CONFIG_ARC_HAS_LLSC */
static inline void arch_spin_lock(arch_spinlock_t *lock)