diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-08-08 03:38:00 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-08-08 03:38:00 +0200 |
commit | dd2384a75d1c046faf068a6352732a204814b86d (patch) | |
tree | 4591d1cced0fe9345c6c1487c30bff07832822eb /arch | |
parent | Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost (diff) | |
parent | ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential backoff (diff) | |
download | linux-dd2384a75d1c046faf068a6352732a204814b86d.tar.xz linux-dd2384a75d1c046faf068a6352732a204814b86d.zip |
Merge tag 'arc-v4.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
"Here's a late pull request for accumulated ARC fixes which came out of
extended testing of the new ARCv2 port with LTP etc. llock/scond
livelock workaround has been reviewed by PeterZ. The changes look a
lot but I've crafted them into finer grained patches for better
tracking later.
I have some more fixes (ARC Futex backend) ready to go but those will
have to wait for tglx to return from vacation.
Summary:
- Enable a reduced config of HS38 (w/o div-rem, ll64...)
- Add software workaround for LLOCK/SCOND livelock
- Fallout of a recent pt_regs update"
* tag 'arc-v4.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential backoff
ARC: Make pt_regs regs unsigned
ARCv2: spinlock/rwlock: Reset retry delay when starting a new spin-wait cycle
ARCv2: spinlock/rwlock/atomics: Delayed retry of failed SCOND with exponential backoff
ARC: LLOCK/SCOND based rwlock
ARC: LLOCK/SCOND based spin_lock
ARC: refactor atomic inline asm operands with symbolic names
Revert "ARCv2: STAR 9000837815 workaround hardware exclusive transactions livelock"
ARCv2: [axs103_smp] Reduce clk for Quad FPGA configs
ARCv2: Fix the peripheral address space detection
ARCv2: allow selection of page size for MMUv4
ARCv2: lib: memset: Don't assume 64-bit load/stores
ARCv2: lib: memcpy: Missing PREFETCHW
ARCv2: add knob for DIV_REV in Kconfig
ARC/time: Migrate to new 'set-state' interface
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arc/Kconfig | 13 | ||||
-rw-r--r-- | arch/arc/Makefile | 10 | ||||
-rw-r--r-- | arch/arc/include/asm/arcregs.h | 7 | ||||
-rw-r--r-- | arch/arc/include/asm/atomic.h | 78 | ||||
-rw-r--r-- | arch/arc/include/asm/ptrace.h | 54 | ||||
-rw-r--r-- | arch/arc/include/asm/spinlock.h | 538 | ||||
-rw-r--r-- | arch/arc/include/asm/spinlock_types.h | 2 | ||||
-rw-r--r-- | arch/arc/include/uapi/asm/ptrace.h | 20 | ||||
-rw-r--r-- | arch/arc/kernel/setup.c | 12 | ||||
-rw-r--r-- | arch/arc/kernel/time.c | 40 | ||||
-rw-r--r-- | arch/arc/lib/memcpy-archs.S | 2 | ||||
-rw-r--r-- | arch/arc/lib/memset-archs.S | 43 | ||||
-rw-r--r-- | arch/arc/plat-axs10x/axs10x.c | 15 |
13 files changed, 718 insertions, 116 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 91cf4055acab..bd4670d1b89b 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -313,11 +313,11 @@ config ARC_PAGE_SIZE_8K config ARC_PAGE_SIZE_16K bool "16KB" - depends on ARC_MMU_V3 + depends on ARC_MMU_V3 || ARC_MMU_V4 config ARC_PAGE_SIZE_4K bool "4KB" - depends on ARC_MMU_V3 + depends on ARC_MMU_V3 || ARC_MMU_V4 endchoice @@ -365,6 +365,11 @@ config ARC_HAS_LLSC default y depends on !ARC_CANT_LLSC +config ARC_STAR_9000923308 + bool "Workaround for llock/scond livelock" + default y + depends on ISA_ARCV2 && SMP && ARC_HAS_LLSC + config ARC_HAS_SWAPE bool "Insn: SWAPE (endian-swap)" default y @@ -379,6 +384,10 @@ config ARC_HAS_LL64 dest operands with 2 possible source operands. default y +config ARC_HAS_DIV_REM + bool "Insn: div, divu, rem, remu" + default y + config ARC_HAS_RTC bool "Local 64-bit r/o cycle counter" default n diff --git a/arch/arc/Makefile b/arch/arc/Makefile index 46d87310220d..8a27a48304a4 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -36,8 +36,16 @@ cflags-$(atleast_gcc44) += -fsection-anchors cflags-$(CONFIG_ARC_HAS_LLSC) += -mlock cflags-$(CONFIG_ARC_HAS_SWAPE) += -mswape +ifdef CONFIG_ISA_ARCV2 + ifndef CONFIG_ARC_HAS_LL64 -cflags-$(CONFIG_ISA_ARCV2) += -mno-ll64 +cflags-y += -mno-ll64 +endif + +ifndef CONFIG_ARC_HAS_DIV_REM +cflags-y += -mno-div-rem +endif + endif cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h index 070f58827a5c..c8f57b8449dc 100644 --- a/arch/arc/include/asm/arcregs.h +++ b/arch/arc/include/asm/arcregs.h @@ -89,11 +89,10 @@ #define ECR_C_BIT_DTLB_LD_MISS 8 #define ECR_C_BIT_DTLB_ST_MISS 9 - /* Auxiliary registers */ #define AUX_IDENTITY 4 #define AUX_INTR_VEC_BASE 0x25 - +#define AUX_NON_VOL 0x5e /* * Floating Pt Registers @@ -240,9 +239,9 @@ struct bcr_extn_xymem { struct bcr_perip { #ifdef CONFIG_CPU_BIG_ENDIAN - unsigned int start:8, pad2:8, sz:8, pad:8; + unsigned int start:8, pad2:8, sz:8, ver:8; #else - unsigned int pad:8, sz:8, pad2:8, start:8; + unsigned int ver:8, sz:8, pad2:8, start:8; #endif }; diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h index 03484cb4d16d..87d18ae53115 100644 --- a/arch/arc/include/asm/atomic.h +++ b/arch/arc/include/asm/atomic.h @@ -23,33 +23,60 @@ #define atomic_set(v, i) (((v)->counter) = (i)) -#ifdef CONFIG_ISA_ARCV2 -#define PREFETCHW " prefetchw [%1] \n" -#else -#define PREFETCHW +#ifdef CONFIG_ARC_STAR_9000923308 + +#define SCOND_FAIL_RETRY_VAR_DEF \ + unsigned int delay = 1, tmp; \ + +#define SCOND_FAIL_RETRY_ASM \ + " bz 4f \n" \ + " ; --- 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 */ \ + "4: ; --- success --- \n" \ + +#define SCOND_FAIL_RETRY_VARS \ + ,[delay] "+&r" (delay),[tmp] "=&r" (tmp) \ + +#else /* !CONFIG_ARC_STAR_9000923308 */ + +#define SCOND_FAIL_RETRY_VAR_DEF + +#define SCOND_FAIL_RETRY_ASM \ + " bnz 1b \n" \ + +#define SCOND_FAIL_RETRY_VARS + #endif #define ATOMIC_OP(op, c_op, asm_op) \ static inline void atomic_##op(int i, atomic_t *v) \ { \ - unsigned int temp; \ + unsigned int val; \ + SCOND_FAIL_RETRY_VAR_DEF \ \ __asm__ __volatile__( \ - "1: \n" \ - PREFETCHW \ - " llock %0, [%1] \n" \ - " " #asm_op " %0, %0, %2 \n" \ - " scond %0, [%1] \n" \ - " bnz 1b \n" \ - : "=&r"(temp) /* Early clobber, to prevent reg reuse */ \ - : "r"(&v->counter), "ir"(i) \ + "1: llock %[val], [%[ctr]] \n" \ + " " #asm_op " %[val], %[val], %[i] \n" \ + " scond %[val], [%[ctr]] \n" \ + " \n" \ + SCOND_FAIL_RETRY_ASM \ + \ + : [val] "=&r" (val) /* Early clobber to prevent reg reuse */ \ + SCOND_FAIL_RETRY_VARS \ + : [ctr] "r" (&v->counter), /* Not "m": llock only supports reg direct addr mode */ \ + [i] "ir" (i) \ : "cc"); \ } \ #define ATOMIC_OP_RETURN(op, c_op, asm_op) \ static inline int atomic_##op##_return(int i, atomic_t *v) \ { \ - unsigned int temp; \ + unsigned int val; \ + SCOND_FAIL_RETRY_VAR_DEF \ \ /* \ * Explicit full memory barrier needed before/after as \ @@ -58,19 +85,21 @@ static inline int atomic_##op##_return(int i, atomic_t *v) \ smp_mb(); \ \ __asm__ __volatile__( \ - "1: \n" \ - PREFETCHW \ - " llock %0, [%1] \n" \ - " " #asm_op " %0, %0, %2 \n" \ - " scond %0, [%1] \n" \ - " bnz 1b \n" \ - : "=&r"(temp) \ - : "r"(&v->counter), "ir"(i) \ + "1: llock %[val], [%[ctr]] \n" \ + " " #asm_op " %[val], %[val], %[i] \n" \ + " scond %[val], [%[ctr]] \n" \ + " \n" \ + SCOND_FAIL_RETRY_ASM \ + \ + : [val] "=&r" (val) \ + SCOND_FAIL_RETRY_VARS \ + : [ctr] "r" (&v->counter), \ + [i] "ir" (i) \ : "cc"); \ \ smp_mb(); \ \ - return temp; \ + return val; \ } #else /* !CONFIG_ARC_HAS_LLSC */ @@ -150,6 +179,9 @@ ATOMIC_OP(and, &=, and) #undef ATOMIC_OPS #undef ATOMIC_OP_RETURN #undef ATOMIC_OP +#undef SCOND_FAIL_RETRY_VAR_DEF +#undef SCOND_FAIL_RETRY_ASM +#undef SCOND_FAIL_RETRY_VARS /** * __atomic_add_unless - add unless the number is a given value diff --git a/arch/arc/include/asm/ptrace.h b/arch/arc/include/asm/ptrace.h index 91694ec1ce95..69095da1fcfd 100644 --- a/arch/arc/include/asm/ptrace.h +++ b/arch/arc/include/asm/ptrace.h @@ -20,20 +20,20 @@ struct pt_regs { /* Real registers */ - long bta; /* bta_l1, bta_l2, erbta */ + unsigned long bta; /* bta_l1, bta_l2, erbta */ - long lp_start, lp_end, lp_count; + unsigned long lp_start, lp_end, lp_count; - long status32; /* status32_l1, status32_l2, erstatus */ - long ret; /* ilink1, ilink2 or eret */ - long blink; - long fp; - long r26; /* gp */ + unsigned long status32; /* status32_l1, status32_l2, erstatus */ + unsigned long ret; /* ilink1, ilink2 or eret */ + unsigned long blink; + unsigned long fp; + unsigned long r26; /* gp */ - long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0; + unsigned long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0; - long sp; /* user/kernel sp depending on where we came from */ - long orig_r0; + unsigned long sp; /* User/Kernel depending on where we came from */ + unsigned long orig_r0; /* * To distinguish bet excp, syscall, irq @@ -55,13 +55,13 @@ struct pt_regs { unsigned long event; }; - long user_r25; + unsigned long user_r25; }; #else struct pt_regs { - long orig_r0; + unsigned long orig_r0; union { struct { @@ -76,26 +76,26 @@ struct pt_regs { unsigned long event; }; - long bta; /* bta_l1, bta_l2, erbta */ + unsigned long bta; /* bta_l1, bta_l2, erbta */ - long user_r25; + unsigned long user_r25; - long r26; /* gp */ - long fp; - long sp; /* user/kernel sp depending on where we came from */ + unsigned long r26; /* gp */ + unsigned long fp; + unsigned long sp; /* user/kernel sp depending on where we came from */ - long r12; + unsigned long r12; /*------- Below list auto saved by h/w -----------*/ - long r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11; + unsigned long r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11; - long blink; - long lp_end, lp_start, lp_count; + unsigned long blink; + unsigned long lp_end, lp_start, lp_count; - long ei, ldi, jli; + unsigned long ei, ldi, jli; - long ret; - long status32; + unsigned long ret; + unsigned long status32; }; #endif @@ -103,10 +103,10 @@ struct pt_regs { /* Callee saved registers - need to be saved only when you are scheduled out */ struct callee_regs { - long r25, r24, r23, r22, r21, r20, r19, r18, r17, r16, r15, r14, r13; + unsigned long r25, r24, r23, r22, r21, r20, r19, r18, r17, r16, r15, r14, r13; }; -#define instruction_pointer(regs) (unsigned long)((regs)->ret) +#define instruction_pointer(regs) ((regs)->ret) #define profile_pc(regs) instruction_pointer(regs) /* return 1 if user mode or 0 if kernel mode */ @@ -142,7 +142,7 @@ struct callee_regs { static inline long regs_return_value(struct pt_regs *regs) { - return regs->r0; + return (long)regs->r0; } #endif /* !__ASSEMBLY__ */ diff --git a/arch/arc/include/asm/spinlock.h b/arch/arc/include/asm/spinlock.h index e1651df6a93d..db8c59d1eaeb 100644 --- a/arch/arc/include/asm/spinlock.h +++ b/arch/arc/include/asm/spinlock.h @@ -18,9 +18,518 @@ #define arch_spin_unlock_wait(x) \ do { while (arch_spin_is_locked(x)) cpu_relax(); } while (0) +#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 tmp = __ARCH_SPIN_LOCK_LOCKED__; + unsigned int val; + + smp_mb(); + + __asm__ __volatile__( + "1: llock %[val], [%[slock]] \n" + " breq %[val], %[LOCKED], 1b \n" /* spin while LOCKED */ + " scond %[LOCKED], [%[slock]] \n" /* acquire */ + " bnz 1b \n" + " \n" + : [val] "=&r" (val) + : [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; + + smp_mb(); + + __asm__ __volatile__( + "1: llock %[val], [%[slock]] \n" + " breq %[val], %[LOCKED], 4f \n" /* already LOCKED, just bail */ + " scond %[LOCKED], [%[slock]] \n" /* acquire */ + " bnz 1b \n" + " mov %[got_it], 1 \n" + "4: \n" + " \n" + : [val] "=&r" (val), + [got_it] "+&r" (got_it) + : [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; + + 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__( + "1: llock %[val], [%[rwlock]] \n" + " brls %[val], %[WR_LOCKED], 1b\n" /* <= 0: spin while write locked */ + " sub %[val], %[val], 1 \n" /* reader lock */ + " scond %[val], [%[rwlock]] \n" + " bnz 1b \n" + " \n" + : [val] "=&r" (val) + : [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; + + smp_mb(); + + __asm__ __volatile__( + "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" + " bnz 1b \n" /* retry if collided with someone */ + " mov %[got_it], 1 \n" + " \n" + "4: ; --- done --- \n" + + : [val] "=&r" (val), + [got_it] "+&r" (got_it) + : [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; + + 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__( + "1: llock %[val], [%[rwlock]] \n" + " brne %[val], %[UNLOCKED], 1b \n" /* while !UNLOCKED spin */ + " mov %[val], %[WR_LOCKED] \n" + " scond %[val], [%[rwlock]] \n" + " bnz 1b \n" + " \n" + : [val] "=&r" (val) + : [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; + + smp_mb(); + + __asm__ __volatile__( + "1: llock %[val], [%[rwlock]] \n" + " brne %[val], %[UNLOCKED], 4f \n" /* !UNLOCKED, bail */ + " mov %[val], %[WR_LOCKED] \n" + " scond %[val], [%[rwlock]] \n" + " bnz 1b \n" /* retry if collided with someone */ + " mov %[got_it], 1 \n" + " \n" + "4: ; --- done --- \n" + + : [val] "=&r" (val), + [got_it] "+&r" (got_it) + : [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) +{ + smp_mb(); + + rw->counter = __ARCH_RW_LOCK_UNLOCKED__; + + 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) +{ + unsigned int val = __ARCH_SPIN_LOCK_LOCKED__; /* * This smp_mb() is technically superfluous, we only need the one @@ -33,7 +542,7 @@ static inline void arch_spin_lock(arch_spinlock_t *lock) __asm__ __volatile__( "1: ex %0, [%1] \n" " breq %0, %2, 1b \n" - : "+&r" (tmp) + : "+&r" (val) : "r"(&(lock->slock)), "ir"(__ARCH_SPIN_LOCK_LOCKED__) : "memory"); @@ -48,26 +557,27 @@ static inline void arch_spin_lock(arch_spinlock_t *lock) smp_mb(); } +/* 1 - lock taken successfully */ static inline int arch_spin_trylock(arch_spinlock_t *lock) { - unsigned int tmp = __ARCH_SPIN_LOCK_LOCKED__; + unsigned int val = __ARCH_SPIN_LOCK_LOCKED__; smp_mb(); __asm__ __volatile__( "1: ex %0, [%1] \n" - : "+r" (tmp) + : "+r" (val) : "r"(&(lock->slock)) : "memory"); smp_mb(); - return (tmp == __ARCH_SPIN_LOCK_UNLOCKED__); + return (val == __ARCH_SPIN_LOCK_UNLOCKED__); } static inline void arch_spin_unlock(arch_spinlock_t *lock) { - unsigned int tmp = __ARCH_SPIN_LOCK_UNLOCKED__; + unsigned int val = __ARCH_SPIN_LOCK_UNLOCKED__; /* * RELEASE barrier: given the instructions avail on ARCv2, full barrier @@ -77,7 +587,7 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) __asm__ __volatile__( " ex %0, [%1] \n" - : "+r" (tmp) + : "+r" (val) : "r"(&(lock->slock)) : "memory"); @@ -90,19 +600,12 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) /* * Read-write spinlocks, allowing multiple readers but only one writer. + * Unfair locking as Writers could be starved indefinitely by Reader(s) * * The spinlock itself is contained in @counter and access to it is * serialized with @lock_mutex. - * - * Unfair locking as Writers could be starved indefinitely by Reader(s) */ -/* Would read_trylock() succeed? */ -#define arch_read_can_lock(x) ((x)->counter > 0) - -/* Would write_trylock() succeed? */ -#define arch_write_can_lock(x) ((x)->counter == __ARCH_RW_LOCK_UNLOCKED__) - /* 1 - lock taken successfully */ static inline int arch_read_trylock(arch_rwlock_t *rw) { @@ -173,6 +676,11 @@ static inline void arch_write_unlock(arch_rwlock_t *rw) arch_spin_unlock(&(rw->lock_mutex)); } +#endif + +#define arch_read_can_lock(x) ((x)->counter > 0) +#define arch_write_can_lock(x) ((x)->counter == __ARCH_RW_LOCK_UNLOCKED__) + #define arch_read_lock_flags(lock, flags) arch_read_lock(lock) #define arch_write_lock_flags(lock, flags) arch_write_lock(lock) diff --git a/arch/arc/include/asm/spinlock_types.h b/arch/arc/include/asm/spinlock_types.h index 662627ced4f2..4e1ef5f650c6 100644 --- a/arch/arc/include/asm/spinlock_types.h +++ b/arch/arc/include/asm/spinlock_types.h @@ -26,7 +26,9 @@ typedef struct { */ typedef struct { volatile unsigned int counter; +#ifndef CONFIG_ARC_HAS_LLSC arch_spinlock_t lock_mutex; +#endif } arch_rwlock_t; #define __ARCH_RW_LOCK_UNLOCKED__ 0x01000000 diff --git a/arch/arc/include/uapi/asm/ptrace.h b/arch/arc/include/uapi/asm/ptrace.h index 76a7739aab1c..0b3ef63d4a03 100644 --- a/arch/arc/include/uapi/asm/ptrace.h +++ b/arch/arc/include/uapi/asm/ptrace.h @@ -32,20 +32,20 @@ */ struct user_regs_struct { - long pad; + unsigned long pad; struct { - long bta, lp_start, lp_end, lp_count; - long status32, ret, blink, fp, gp; - long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0; - long sp; + unsigned long bta, lp_start, lp_end, lp_count; + unsigned long status32, ret, blink, fp, gp; + unsigned long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0; + unsigned long sp; } scratch; - long pad2; + unsigned long pad2; struct { - long r25, r24, r23, r22, r21, r20; - long r19, r18, r17, r16, r15, r14, r13; + unsigned long r25, r24, r23, r22, r21, r20; + unsigned long r19, r18, r17, r16, r15, r14, r13; } callee; - long efa; /* break pt addr, for break points in delay slots */ - long stop_pc; /* give dbg stop_pc after ensuring brkpt trap */ + unsigned long efa; /* break pt addr, for break points in delay slots */ + unsigned long stop_pc; /* give dbg stop_pc after ensuring brkpt trap */ }; #endif /* !__ASSEMBLY__ */ diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c index 18cc01591c96..cabde9dc0696 100644 --- a/arch/arc/kernel/setup.c +++ b/arch/arc/kernel/setup.c @@ -47,6 +47,7 @@ static void read_arc_build_cfg_regs(void) struct bcr_perip uncached_space; struct bcr_generic bcr; struct cpuinfo_arc *cpu = &cpuinfo_arc700[smp_processor_id()]; + unsigned long perip_space; FIX_PTR(cpu); READ_BCR(AUX_IDENTITY, cpu->core); @@ -56,7 +57,12 @@ static void read_arc_build_cfg_regs(void) cpu->vec_base = read_aux_reg(AUX_INTR_VEC_BASE); READ_BCR(ARC_REG_D_UNCACH_BCR, uncached_space); - BUG_ON((uncached_space.start << 24) != ARC_UNCACHED_ADDR_SPACE); + if (uncached_space.ver < 3) + perip_space = uncached_space.start << 24; + else + perip_space = read_aux_reg(AUX_NON_VOL) & 0xF0000000; + + BUG_ON(perip_space != ARC_UNCACHED_ADDR_SPACE); READ_BCR(ARC_REG_MUL_BCR, cpu->extn_mpy); @@ -330,6 +336,10 @@ static void arc_chk_core_config(void) pr_warn("CONFIG_ARC_FPU_SAVE_RESTORE needed for working apps\n"); else if (!cpu->extn.fpu_dp && fpu_enabled) panic("FPU non-existent, disable CONFIG_ARC_FPU_SAVE_RESTORE\n"); + + if (is_isa_arcv2() && IS_ENABLED(CONFIG_SMP) && cpu->isa.atomic && + !IS_ENABLED(CONFIG_ARC_STAR_9000923308)) + panic("llock/scond livelock workaround missing\n"); } /* diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c index 3364d2bbc515..4294761a2b3e 100644 --- a/arch/arc/kernel/time.c +++ b/arch/arc/kernel/time.c @@ -203,34 +203,24 @@ static int arc_clkevent_set_next_event(unsigned long delta, return 0; } -static void arc_clkevent_set_mode(enum clock_event_mode mode, - struct clock_event_device *dev) +static int arc_clkevent_set_periodic(struct clock_event_device *dev) { - switch (mode) { - case CLOCK_EVT_MODE_PERIODIC: - /* - * At X Hz, 1 sec = 1000ms -> X cycles; - * 10ms -> X / 100 cycles - */ - arc_timer_event_setup(arc_get_core_freq() / HZ); - break; - case CLOCK_EVT_MODE_ONESHOT: - break; - default: - break; - } - - return; + /* + * At X Hz, 1 sec = 1000ms -> X cycles; + * 10ms -> X / 100 cycles + */ + arc_timer_event_setup(arc_get_core_freq() / HZ); + return 0; } static DEFINE_PER_CPU(struct clock_event_device, arc_clockevent_device) = { - .name = "ARC Timer0", - .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, - .mode = CLOCK_EVT_MODE_UNUSED, - .rating = 300, - .irq = TIMER0_IRQ, /* hardwired, no need for resources */ - .set_next_event = arc_clkevent_set_next_event, - .set_mode = arc_clkevent_set_mode, + .name = "ARC Timer0", + .features = CLOCK_EVT_FEAT_ONESHOT | + CLOCK_EVT_FEAT_PERIODIC, + .rating = 300, + .irq = TIMER0_IRQ, /* hardwired, no need for resources */ + .set_next_event = arc_clkevent_set_next_event, + .set_state_periodic = arc_clkevent_set_periodic, }; static irqreturn_t timer_irq_handler(int irq, void *dev_id) @@ -240,7 +230,7 @@ static irqreturn_t timer_irq_handler(int irq, void *dev_id) * irq_set_chip_and_handler() asked for handle_percpu_devid_irq() */ struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device); - int irq_reenable = evt->mode == CLOCK_EVT_MODE_PERIODIC; + int irq_reenable = clockevent_state_periodic(evt); /* * Any write to CTRL reg ACks the interrupt, we rewrite the diff --git a/arch/arc/lib/memcpy-archs.S b/arch/arc/lib/memcpy-archs.S index 1b2b3acfed52..0cab0b8a57c5 100644 --- a/arch/arc/lib/memcpy-archs.S +++ b/arch/arc/lib/memcpy-archs.S @@ -206,7 +206,7 @@ unalignedOffby3: ld.ab r6, [r1, 4] prefetch [r1, 28] ;Prefetch the next read location ld.ab r8, [r1,4] - prefetch [r3, 32] ;Prefetch the next write location + prefetchw [r3, 32] ;Prefetch the next write location SHIFT_1 (r7, r6, 8) or r7, r7, r5 diff --git a/arch/arc/lib/memset-archs.S b/arch/arc/lib/memset-archs.S index 92d573c734b5..365b18364815 100644 --- a/arch/arc/lib/memset-archs.S +++ b/arch/arc/lib/memset-archs.S @@ -10,12 +10,6 @@ #undef PREALLOC_NOT_AVAIL -#ifdef PREALLOC_NOT_AVAIL -#define PREWRITE(A,B) prefetchw [(A),(B)] -#else -#define PREWRITE(A,B) prealloc [(A),(B)] -#endif - ENTRY(memset) prefetchw [r0] ; Prefetch the write location mov.f 0, r2 @@ -51,9 +45,15 @@ ENTRY(memset) ;;; Convert len to Dwords, unfold x8 lsr.f lp_count, lp_count, 6 + lpnz @.Lset64bytes ;; LOOP START - PREWRITE(r3, 64) ;Prefetch the next write location +#ifdef PREALLOC_NOT_AVAIL + prefetchw [r3, 64] ;Prefetch the next write location +#else + prealloc [r3, 64] +#endif +#ifdef CONFIG_ARC_HAS_LL64 std.ab r4, [r3, 8] std.ab r4, [r3, 8] std.ab r4, [r3, 8] @@ -62,16 +62,45 @@ ENTRY(memset) std.ab r4, [r3, 8] std.ab r4, [r3, 8] std.ab r4, [r3, 8] +#else + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] +#endif .Lset64bytes: lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes lpnz .Lset32bytes ;; LOOP START prefetchw [r3, 32] ;Prefetch the next write location +#ifdef CONFIG_ARC_HAS_LL64 std.ab r4, [r3, 8] std.ab r4, [r3, 8] std.ab r4, [r3, 8] std.ab r4, [r3, 8] +#else + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] + st.ab r4, [r3, 4] +#endif .Lset32bytes: and.f lp_count, r2, 0x1F ;Last remaining 31 bytes diff --git a/arch/arc/plat-axs10x/axs10x.c b/arch/arc/plat-axs10x/axs10x.c index 99f7da513a48..e7769c3ab5f2 100644 --- a/arch/arc/plat-axs10x/axs10x.c +++ b/arch/arc/plat-axs10x/axs10x.c @@ -389,6 +389,21 @@ axs103_set_freq(unsigned int id, unsigned int fd, unsigned int od) static void __init axs103_early_init(void) { + /* + * AXS103 configurations for SMP/QUAD configurations share device tree + * which defaults to 90 MHz. However recent failures of Quad config + * revealed P&R timing violations so clamp it down to safe 50 MHz + * Instead of duplicating defconfig/DT for SMP/QUAD, add a small hack + * + * This hack is really hacky as of now. Fix it properly by getting the + * number of cores as return value of platform's early SMP callback + */ +#ifdef CONFIG_ARC_MCIP + unsigned int num_cores = (read_aux_reg(ARC_REG_MCIP_BCR) >> 16) & 0x3F; + if (num_cores > 2) + arc_set_core_freq(50 * 1000000); +#endif + switch (arc_get_core_freq()/1000000) { case 33: axs103_set_freq(1, 1, 1); |