summaryrefslogtreecommitdiffstats
path: root/lib/atomic64.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
commitcf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch)
tree757a3d280760c654767631cab5ad8af2d86d1848 /lib/atomic64.c
downloadlinux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz
linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
Diffstat (limited to 'lib/atomic64.c')
-rw-r--r--lib/atomic64.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/lib/atomic64.c b/lib/atomic64.c
new file mode 100644
index 000000000..1a72bba36
--- /dev/null
+++ b/lib/atomic64.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Generic implementation of 64-bit atomics using spinlocks,
+ * useful on processors that don't have 64-bit atomic instructions.
+ *
+ * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
+ */
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/atomic.h>
+
+/*
+ * We use a hashed array of spinlocks to provide exclusive access
+ * to each atomic64_t variable. Since this is expected to used on
+ * systems with small numbers of CPUs (<= 4 or so), we use a
+ * relatively small array of 16 spinlocks to avoid wasting too much
+ * memory on the spinlock array.
+ */
+#define NR_LOCKS 16
+
+/*
+ * Ensure each lock is in a separate cacheline.
+ */
+static union {
+ arch_spinlock_t lock;
+ char pad[L1_CACHE_BYTES];
+} atomic64_lock[NR_LOCKS] __cacheline_aligned_in_smp = {
+ [0 ... (NR_LOCKS - 1)] = {
+ .lock = __ARCH_SPIN_LOCK_UNLOCKED,
+ },
+};
+
+static inline arch_spinlock_t *lock_addr(const atomic64_t *v)
+{
+ unsigned long addr = (unsigned long) v;
+
+ addr >>= L1_CACHE_SHIFT;
+ addr ^= (addr >> 8) ^ (addr >> 16);
+ return &atomic64_lock[addr & (NR_LOCKS - 1)].lock;
+}
+
+s64 generic_atomic64_read(const atomic64_t *v)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+ s64 val;
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ val = v->counter;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+ return val;
+}
+EXPORT_SYMBOL(generic_atomic64_read);
+
+void generic_atomic64_set(atomic64_t *v, s64 i)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ v->counter = i;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(generic_atomic64_set);
+
+#define ATOMIC64_OP(op, c_op) \
+void generic_atomic64_##op(s64 a, atomic64_t *v) \
+{ \
+ unsigned long flags; \
+ arch_spinlock_t *lock = lock_addr(v); \
+ \
+ local_irq_save(flags); \
+ arch_spin_lock(lock); \
+ v->counter c_op a; \
+ arch_spin_unlock(lock); \
+ local_irq_restore(flags); \
+} \
+EXPORT_SYMBOL(generic_atomic64_##op);
+
+#define ATOMIC64_OP_RETURN(op, c_op) \
+s64 generic_atomic64_##op##_return(s64 a, atomic64_t *v) \
+{ \
+ unsigned long flags; \
+ arch_spinlock_t *lock = lock_addr(v); \
+ s64 val; \
+ \
+ local_irq_save(flags); \
+ arch_spin_lock(lock); \
+ val = (v->counter c_op a); \
+ arch_spin_unlock(lock); \
+ local_irq_restore(flags); \
+ return val; \
+} \
+EXPORT_SYMBOL(generic_atomic64_##op##_return);
+
+#define ATOMIC64_FETCH_OP(op, c_op) \
+s64 generic_atomic64_fetch_##op(s64 a, atomic64_t *v) \
+{ \
+ unsigned long flags; \
+ arch_spinlock_t *lock = lock_addr(v); \
+ s64 val; \
+ \
+ local_irq_save(flags); \
+ arch_spin_lock(lock); \
+ val = v->counter; \
+ v->counter c_op a; \
+ arch_spin_unlock(lock); \
+ local_irq_restore(flags); \
+ return val; \
+} \
+EXPORT_SYMBOL(generic_atomic64_fetch_##op);
+
+#define ATOMIC64_OPS(op, c_op) \
+ ATOMIC64_OP(op, c_op) \
+ ATOMIC64_OP_RETURN(op, c_op) \
+ ATOMIC64_FETCH_OP(op, c_op)
+
+ATOMIC64_OPS(add, +=)
+ATOMIC64_OPS(sub, -=)
+
+#undef ATOMIC64_OPS
+#define ATOMIC64_OPS(op, c_op) \
+ ATOMIC64_OP(op, c_op) \
+ ATOMIC64_FETCH_OP(op, c_op)
+
+ATOMIC64_OPS(and, &=)
+ATOMIC64_OPS(or, |=)
+ATOMIC64_OPS(xor, ^=)
+
+#undef ATOMIC64_OPS
+#undef ATOMIC64_FETCH_OP
+#undef ATOMIC64_OP
+
+s64 generic_atomic64_dec_if_positive(atomic64_t *v)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+ s64 val;
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ val = v->counter - 1;
+ if (val >= 0)
+ v->counter = val;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+ return val;
+}
+EXPORT_SYMBOL(generic_atomic64_dec_if_positive);
+
+s64 generic_atomic64_cmpxchg(atomic64_t *v, s64 o, s64 n)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+ s64 val;
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ val = v->counter;
+ if (val == o)
+ v->counter = n;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+ return val;
+}
+EXPORT_SYMBOL(generic_atomic64_cmpxchg);
+
+s64 generic_atomic64_xchg(atomic64_t *v, s64 new)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+ s64 val;
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ val = v->counter;
+ v->counter = new;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+ return val;
+}
+EXPORT_SYMBOL(generic_atomic64_xchg);
+
+s64 generic_atomic64_fetch_add_unless(atomic64_t *v, s64 a, s64 u)
+{
+ unsigned long flags;
+ arch_spinlock_t *lock = lock_addr(v);
+ s64 val;
+
+ local_irq_save(flags);
+ arch_spin_lock(lock);
+ val = v->counter;
+ if (val != u)
+ v->counter += a;
+ arch_spin_unlock(lock);
+ local_irq_restore(flags);
+
+ return val;
+}
+EXPORT_SYMBOL(generic_atomic64_fetch_add_unless);