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authorLinus Torvalds <torvalds@linux-foundation.org>2015-08-08 04:38:00 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-08-08 04:38:00 +0300
commitdd2384a75d1c046faf068a6352732a204814b86d (patch)
tree4591d1cced0fe9345c6c1487c30bff07832822eb
parentb3b98a551de18c7983e63ade9490fe52b9bbee6f (diff)
parent10971638701dedadb58c88ce4d31c9375b224ed6 (diff)
downloadlinux-dd2384a75d1c046faf068a6352732a204814b86d.tar.bz2
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
-rw-r--r--arch/arc/Kconfig13
-rw-r--r--arch/arc/Makefile10
-rw-r--r--arch/arc/include/asm/arcregs.h7
-rw-r--r--arch/arc/include/asm/atomic.h78
-rw-r--r--arch/arc/include/asm/ptrace.h54
-rw-r--r--arch/arc/include/asm/spinlock.h538
-rw-r--r--arch/arc/include/asm/spinlock_types.h2
-rw-r--r--arch/arc/include/uapi/asm/ptrace.h20
-rw-r--r--arch/arc/kernel/setup.c12
-rw-r--r--arch/arc/kernel/time.c40
-rw-r--r--arch/arc/lib/memcpy-archs.S2
-rw-r--r--arch/arc/lib/memset-archs.S43
-rw-r--r--arch/arc/plat-axs10x/axs10x.c15
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);