summaryrefslogtreecommitdiffstats
path: root/arch/parisc/include/asm/bitops.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/parisc/include/asm/bitops.h
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/parisc/include/asm/bitops.h209
1 files changed, 209 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/bitops.h b/arch/parisc/include/asm/bitops.h
new file mode 100644
index 000000000..0ec9cfc51
--- /dev/null
+++ b/arch/parisc/include/asm/bitops.h
@@ -0,0 +1,209 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _PARISC_BITOPS_H
+#define _PARISC_BITOPS_H
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <linux/compiler.h>
+#include <asm/types.h>
+#include <asm/byteorder.h>
+#include <asm/barrier.h>
+#include <linux/atomic.h>
+
+/* See http://marc.theaimsgroup.com/?t=108826637900003 for discussion
+ * on use of volatile and __*_bit() (set/clear/change):
+ * *_bit() want use of volatile.
+ * __*_bit() are "relaxed" and don't use spinlock or volatile.
+ */
+
+static __inline__ void set_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long flags;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ *addr |= mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+}
+
+static __inline__ void clear_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long flags;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ *addr &= ~mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+}
+
+static __inline__ void change_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long flags;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ *addr ^= mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+}
+
+static __inline__ int test_and_set_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long old;
+ unsigned long flags;
+ int set;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ old = *addr;
+ set = (old & mask) ? 1 : 0;
+ if (!set)
+ *addr = old | mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+
+ return set;
+}
+
+static __inline__ int test_and_clear_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long old;
+ unsigned long flags;
+ int set;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ old = *addr;
+ set = (old & mask) ? 1 : 0;
+ if (set)
+ *addr = old & ~mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+
+ return set;
+}
+
+static __inline__ int test_and_change_bit(int nr, volatile unsigned long * addr)
+{
+ unsigned long mask = BIT_MASK(nr);
+ unsigned long oldbit;
+ unsigned long flags;
+
+ addr += BIT_WORD(nr);
+ _atomic_spin_lock_irqsave(addr, flags);
+ oldbit = *addr;
+ *addr = oldbit ^ mask;
+ _atomic_spin_unlock_irqrestore(addr, flags);
+
+ return (oldbit & mask) ? 1 : 0;
+}
+
+#include <asm-generic/bitops/non-atomic.h>
+
+/**
+ * __ffs - find first bit in word. returns 0 to "BITS_PER_LONG-1".
+ * @word: The word to search
+ *
+ * __ffs() return is undefined if no bit is set.
+ *
+ * 32-bit fast __ffs by LaMont Jones "lamont At hp com".
+ * 64-bit enhancement by Grant Grundler "grundler At parisc-linux org".
+ * (with help from willy/jejb to get the semantics right)
+ *
+ * This algorithm avoids branches by making use of nullification.
+ * One side effect of "extr" instructions is it sets PSW[N] bit.
+ * How PSW[N] (nullify next insn) gets set is determined by the
+ * "condition" field (eg "<>" or "TR" below) in the extr* insn.
+ * Only the 1st and one of either the 2cd or 3rd insn will get executed.
+ * Each set of 3 insn will get executed in 2 cycles on PA8x00 vs 16 or so
+ * cycles for each mispredicted branch.
+ */
+
+static __inline__ unsigned long __ffs(unsigned long x)
+{
+ unsigned long ret;
+
+ __asm__(
+#ifdef CONFIG_64BIT
+ " ldi 63,%1\n"
+ " extrd,u,*<> %0,63,32,%%r0\n"
+ " extrd,u,*TR %0,31,32,%0\n" /* move top 32-bits down */
+ " addi -32,%1,%1\n"
+#else
+ " ldi 31,%1\n"
+#endif
+ " extru,<> %0,31,16,%%r0\n"
+ " extru,TR %0,15,16,%0\n" /* xxxx0000 -> 0000xxxx */
+ " addi -16,%1,%1\n"
+ " extru,<> %0,31,8,%%r0\n"
+ " extru,TR %0,23,8,%0\n" /* 0000xx00 -> 000000xx */
+ " addi -8,%1,%1\n"
+ " extru,<> %0,31,4,%%r0\n"
+ " extru,TR %0,27,4,%0\n" /* 000000x0 -> 0000000x */
+ " addi -4,%1,%1\n"
+ " extru,<> %0,31,2,%%r0\n"
+ " extru,TR %0,29,2,%0\n" /* 0000000y, 1100b -> 0011b */
+ " addi -2,%1,%1\n"
+ " extru,= %0,31,1,%%r0\n" /* check last bit */
+ " addi -1,%1,%1\n"
+ : "+r" (x), "=r" (ret) );
+ return ret;
+}
+
+#include <asm-generic/bitops/ffz.h>
+
+/*
+ * ffs: find first bit set. returns 1 to BITS_PER_LONG or 0 (if none set)
+ * This is defined the same way as the libc and compiler builtin
+ * ffs routines, therefore differs in spirit from the above ffz (man ffs).
+ */
+static __inline__ int ffs(int x)
+{
+ return x ? (__ffs((unsigned long)x) + 1) : 0;
+}
+
+/*
+ * fls: find last (most significant) bit set.
+ * fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+
+static __inline__ int fls(unsigned int x)
+{
+ int ret;
+ if (!x)
+ return 0;
+
+ __asm__(
+ " ldi 1,%1\n"
+ " extru,<> %0,15,16,%%r0\n"
+ " zdep,TR %0,15,16,%0\n" /* xxxx0000 */
+ " addi 16,%1,%1\n"
+ " extru,<> %0,7,8,%%r0\n"
+ " zdep,TR %0,23,24,%0\n" /* xx000000 */
+ " addi 8,%1,%1\n"
+ " extru,<> %0,3,4,%%r0\n"
+ " zdep,TR %0,27,28,%0\n" /* x0000000 */
+ " addi 4,%1,%1\n"
+ " extru,<> %0,1,2,%%r0\n"
+ " zdep,TR %0,29,30,%0\n" /* y0000000 (y&3 = 0) */
+ " addi 2,%1,%1\n"
+ " extru,= %0,0,1,%%r0\n"
+ " addi 1,%1,%1\n" /* if y & 8, add 1 */
+ : "+r" (x), "=r" (ret) );
+
+ return ret;
+}
+
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/hweight.h>
+#include <asm-generic/bitops/lock.h>
+#include <asm-generic/bitops/sched.h>
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic-setbit.h>
+
+#endif /* _PARISC_BITOPS_H */