linux_dsm_epyc7002/arch/mips/include/asm/atomic.h
Linus Torvalds e5a32b5b21 Here are the main MIPS changes for 4.19.
An overview of the general architecture changes:
 
   - Massive DMA ops refactoring from Christoph Hellwig (huzzah for
     deleting crufty code!).
 
   - We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes & corresponding
     regsets to expose DSP ASE & floating point mode state respectively,
     both for live debugging & core dumps.
 
   - We better optimize our code by hard-coding cpu_has_* macros at
     compile time where their values are known due to the ISA revision
     that the kernel build is targeting.
 
   - The EJTAG exception handler now better handles SMP systems, where it
     was previously possible for CPUs to clobber a register value saved
     by another CPU.
 
   - Our implementation of memset() gained a couple of fixes for MIPSr6
     systems to return correct values in some cases where stores fault.
 
   - We now implement ioremap_wc() using the uncached-accelerated cache
     coherency attribute where supported, which is detected during boot,
     and fall back to plain uncached access where necessary. The
     MIPS-specific (and unused in tree) ioremap_uncached_accelerated() &
     ioremap_cacheable_cow() are removed.
 
   - The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP
     systems by reworking the way we ensure remote CPUs that may be
     running threads within the affected process switch mode.
 
   - Systems using the MIPS Coherence Manager will now set the
     MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache
     maintenance overhead when flushing the icache.
 
   - A few fixes were made for building with clang/LLVM, which
     now sucessfully builds kernels for many of our platforms.
 
   - Miscellaneous cleanups all over.
 
 And some platform-specific changes:
 
   - ar7 gained stubs for a few clock API functions to fix build failures
     for some drivers.
 
   - ath79 gained support for a few new SoCs, a few fixes & better
     gpio-keys support.
 
   - Ci20 now exposes its SPI bus using the spi-gpio driver.
 
   - The generic platform can now auto-detect a suitable value for
     PHYS_OFFSET based upon the memory map described by the device tree,
     allowing us to avoid wasting memory on page book-keeping for systems
     where RAM starts at a non-zero physical address.
 
   - Ingenic systems using the jz4740 platform code now link their
     vmlinuz higher to allow for kernels of a realistic size.
 
   - Loongson32 now builds the kernel targeting MIPSr1 rather than MIPSr2
     to avoid CPU errata.
 
   - Loongson64 gains a couple of fixes, a workaround for a write
     buffering issue & support for the Loongson 3A R3.1 CPU.
 
   - Malta now uses the piix4-poweroff driver to handle powering down.
 
   - Microsemi Ocelot gained support for its SPI bus & NOR flash, its
     second MDIO bus and can now be supported by a FIT/.itb image.
 
   - Octeon saw a bunch of header cleanups which remove a lot of
     duplicate or unused code.
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Merge tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:
 "Here are the main MIPS changes for 4.19.

  An overview of the general architecture changes:

   - Massive DMA ops refactoring from Christoph Hellwig (huzzah for
     deleting crufty code!).

   - We introduce NT_MIPS_DSP & NT_MIPS_FP_MODE ELF notes &
     corresponding regsets to expose DSP ASE & floating point mode state
     respectively, both for live debugging & core dumps.

   - We better optimize our code by hard-coding cpu_has_* macros at
     compile time where their values are known due to the ISA revision
     that the kernel build is targeting.

   - The EJTAG exception handler now better handles SMP systems, where
     it was previously possible for CPUs to clobber a register value
     saved by another CPU.

   - Our implementation of memset() gained a couple of fixes for MIPSr6
     systems to return correct values in some cases where stores fault.

   - We now implement ioremap_wc() using the uncached-accelerated cache
     coherency attribute where supported, which is detected during boot,
     and fall back to plain uncached access where necessary. The
     MIPS-specific (and unused in tree) ioremap_uncached_accelerated() &
     ioremap_cacheable_cow() are removed.

   - The prctl(PR_SET_FP_MODE, ...) syscall is better supported for SMP
     systems by reworking the way we ensure remote CPUs that may be
     running threads within the affected process switch mode.

   - Systems using the MIPS Coherence Manager will now set the
     MIPS_IC_SNOOPS_REMOTE flag to avoid some unnecessary cache
     maintenance overhead when flushing the icache.

   - A few fixes were made for building with clang/LLVM, which now
     sucessfully builds kernels for many of our platforms.

   - Miscellaneous cleanups all over.

  And some platform-specific changes:

   - ar7 gained stubs for a few clock API functions to fix build
     failures for some drivers.

   - ath79 gained support for a few new SoCs, a few fixes & better
     gpio-keys support.

   - Ci20 now exposes its SPI bus using the spi-gpio driver.

   - The generic platform can now auto-detect a suitable value for
     PHYS_OFFSET based upon the memory map described by the device tree,
     allowing us to avoid wasting memory on page book-keeping for
     systems where RAM starts at a non-zero physical address.

   - Ingenic systems using the jz4740 platform code now link their
     vmlinuz higher to allow for kernels of a realistic size.

   - Loongson32 now builds the kernel targeting MIPSr1 rather than
     MIPSr2 to avoid CPU errata.

   - Loongson64 gains a couple of fixes, a workaround for a write
     buffering issue & support for the Loongson 3A R3.1 CPU.

   - Malta now uses the piix4-poweroff driver to handle powering down.

   - Microsemi Ocelot gained support for its SPI bus & NOR flash, its
     second MDIO bus and can now be supported by a FIT/.itb image.

   - Octeon saw a bunch of header cleanups which remove a lot of
     duplicate or unused code"

* tag 'mips_4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (123 commits)
  MIPS: Remove remnants of UASM_ISA
  MIPS: netlogic: xlr: Remove erroneous check in nlm_fmn_send()
  MIPS: VDSO: Force link endianness
  MIPS: Always specify -EB or -EL when using clang
  MIPS: Use dins to simplify __write_64bit_c0_split()
  MIPS: Use read-write output operand in __write_64bit_c0_split()
  MIPS: Avoid using array as parameter to write_c0_kpgd()
  MIPS: vdso: Allow clang's --target flag in VDSO cflags
  MIPS: genvdso: Remove GOT checks
  MIPS: Remove obsolete MIPS checks for DST node "chosen@0"
  MIPS: generic: Remove input symbols from defconfig
  MIPS: Delete unused code in linux32.c
  MIPS: Remove unused sys_32_mmap2
  MIPS: Remove nabi_no_regargs
  mips: dts: mscc: enable spi and NOR flash support on ocelot PCB123
  mips: dts: mscc: Add spi on Ocelot
  MIPS: Loongson: Merge load addresses
  MIPS: Loongson: Set Loongson32 to MIPS32R1
  MIPS: mscc: ocelot: add interrupt controller properties to GPIO controller
  MIPS: generic: Select MIPS_AUTO_PFN_OFFSET
  ...
2018-08-13 19:24:32 -07:00

424 lines
12 KiB
C

/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*
* But use these as seldom as possible since they are much more slower
* than regular operations.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996, 97, 99, 2000, 03, 04, 06 by Ralf Baechle
*/
#ifndef _ASM_ATOMIC_H
#define _ASM_ATOMIC_H
#include <linux/irqflags.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/compiler.h>
#include <asm/cpu-features.h>
#include <asm/cmpxchg.h>
#include <asm/war.h>
/*
* Using a branch-likely instruction to check the result of an sc instruction
* works around a bug present in R10000 CPUs prior to revision 3.0 that could
* cause ll-sc sequences to execute non-atomically.
*/
#if R10000_LLSC_WAR
# define __scbeqz "beqzl"
#else
# define __scbeqz "beqz"
#endif
#define ATOMIC_INIT(i) { (i) }
/*
* atomic_read - read atomic variable
* @v: pointer of type atomic_t
*
* Atomically reads the value of @v.
*/
#define atomic_read(v) READ_ONCE((v)->counter)
/*
* atomic_set - set atomic variable
* @v: pointer of type atomic_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*/
#define atomic_set(v, i) WRITE_ONCE((v)->counter, (i))
#define ATOMIC_OP(op, c_op, asm_op) \
static __inline__ void atomic_##op(int i, atomic_t * v) \
{ \
if (kernel_uses_llsc) { \
int temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: ll %0, %1 # atomic_" #op " \n" \
" " #asm_op " %0, %2 \n" \
" sc %0, %1 \n" \
"\t" __scbeqz " %0, 1b \n" \
" .set mips0 \n" \
: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
}
#define ATOMIC_OP_RETURN(op, c_op, asm_op) \
static __inline__ int atomic_##op##_return_relaxed(int i, atomic_t * v) \
{ \
int result; \
\
if (kernel_uses_llsc) { \
int temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: ll %1, %2 # atomic_" #op "_return \n" \
" " #asm_op " %0, %1, %3 \n" \
" sc %0, %2 \n" \
"\t" __scbeqz " %0, 1b \n" \
" " #asm_op " %0, %1, %3 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
result c_op i; \
v->counter = result; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC_FETCH_OP(op, c_op, asm_op) \
static __inline__ int atomic_fetch_##op##_relaxed(int i, atomic_t * v) \
{ \
int result; \
\
if (kernel_uses_llsc) { \
int temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: ll %1, %2 # atomic_fetch_" #op " \n" \
" " #asm_op " %0, %1, %3 \n" \
" sc %0, %2 \n" \
"\t" __scbeqz " %0, 1b \n" \
" move %0, %1 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_OP_RETURN(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(add, +=, addu)
ATOMIC_OPS(sub, -=, subu)
#define atomic_add_return_relaxed atomic_add_return_relaxed
#define atomic_sub_return_relaxed atomic_sub_return_relaxed
#define atomic_fetch_add_relaxed atomic_fetch_add_relaxed
#define atomic_fetch_sub_relaxed atomic_fetch_sub_relaxed
#undef ATOMIC_OPS
#define ATOMIC_OPS(op, c_op, asm_op) \
ATOMIC_OP(op, c_op, asm_op) \
ATOMIC_FETCH_OP(op, c_op, asm_op)
ATOMIC_OPS(and, &=, and)
ATOMIC_OPS(or, |=, or)
ATOMIC_OPS(xor, ^=, xor)
#define atomic_fetch_and_relaxed atomic_fetch_and_relaxed
#define atomic_fetch_or_relaxed atomic_fetch_or_relaxed
#define atomic_fetch_xor_relaxed atomic_fetch_xor_relaxed
#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
/*
* atomic_sub_if_positive - conditionally subtract integer from atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically test @v and subtract @i if @v is greater or equal than @i.
* The function returns the old value of @v minus @i.
*/
static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
{
int result;
smp_mb__before_llsc();
if (kernel_uses_llsc) {
int temp;
__asm__ __volatile__(
" .set "MIPS_ISA_LEVEL" \n"
"1: ll %1, %2 # atomic_sub_if_positive\n"
" subu %0, %1, %3 \n"
" move %1, %0 \n"
" bltz %0, 1f \n"
" sc %1, %2 \n"
"\t" __scbeqz " %1, 1b \n"
"1: \n"
" .set mips0 \n"
: "=&r" (result), "=&r" (temp),
"+" GCC_OFF_SMALL_ASM() (v->counter)
: "Ir" (i));
} else {
unsigned long flags;
raw_local_irq_save(flags);
result = v->counter;
result -= i;
if (result >= 0)
v->counter = result;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return result;
}
#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
/*
* atomic_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic_t
*/
#define atomic_dec_if_positive(v) atomic_sub_if_positive(1, v)
#ifdef CONFIG_64BIT
#define ATOMIC64_INIT(i) { (i) }
/*
* atomic64_read - read atomic variable
* @v: pointer of type atomic64_t
*
*/
#define atomic64_read(v) READ_ONCE((v)->counter)
/*
* atomic64_set - set atomic variable
* @v: pointer of type atomic64_t
* @i: required value
*/
#define atomic64_set(v, i) WRITE_ONCE((v)->counter, (i))
#define ATOMIC64_OP(op, c_op, asm_op) \
static __inline__ void atomic64_##op(long i, atomic64_t * v) \
{ \
if (kernel_uses_llsc) { \
long temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: lld %0, %1 # atomic64_" #op " \n" \
" " #asm_op " %0, %2 \n" \
" scd %0, %1 \n" \
"\t" __scbeqz " %0, 1b \n" \
" .set mips0 \n" \
: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
}
#define ATOMIC64_OP_RETURN(op, c_op, asm_op) \
static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v) \
{ \
long result; \
\
if (kernel_uses_llsc) { \
long temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: lld %1, %2 # atomic64_" #op "_return\n" \
" " #asm_op " %0, %1, %3 \n" \
" scd %0, %2 \n" \
"\t" __scbeqz " %0, 1b \n" \
" " #asm_op " %0, %1, %3 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
result c_op i; \
v->counter = result; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC64_FETCH_OP(op, c_op, asm_op) \
static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v) \
{ \
long result; \
\
if (kernel_uses_llsc && R10000_LLSC_WAR) { \
long temp; \
\
__asm__ __volatile__( \
" .set "MIPS_ISA_LEVEL" \n" \
"1: lld %1, %2 # atomic64_fetch_" #op "\n" \
" " #asm_op " %0, %1, %3 \n" \
" scd %0, %2 \n" \
"\t" __scbeqz " %0, 1b \n" \
" move %0, %1 \n" \
" .set mips0 \n" \
: "=&r" (result), "=&r" (temp), \
"+" GCC_OFF_SMALL_ASM() (v->counter) \
: "Ir" (i)); \
} else { \
unsigned long flags; \
\
raw_local_irq_save(flags); \
result = v->counter; \
v->counter c_op i; \
raw_local_irq_restore(flags); \
} \
\
return result; \
}
#define ATOMIC64_OPS(op, c_op, asm_op) \
ATOMIC64_OP(op, c_op, asm_op) \
ATOMIC64_OP_RETURN(op, c_op, asm_op) \
ATOMIC64_FETCH_OP(op, c_op, asm_op)
ATOMIC64_OPS(add, +=, daddu)
ATOMIC64_OPS(sub, -=, dsubu)
#define atomic64_add_return_relaxed atomic64_add_return_relaxed
#define atomic64_sub_return_relaxed atomic64_sub_return_relaxed
#define atomic64_fetch_add_relaxed atomic64_fetch_add_relaxed
#define atomic64_fetch_sub_relaxed atomic64_fetch_sub_relaxed
#undef ATOMIC64_OPS
#define ATOMIC64_OPS(op, c_op, asm_op) \
ATOMIC64_OP(op, c_op, asm_op) \
ATOMIC64_FETCH_OP(op, c_op, asm_op)
ATOMIC64_OPS(and, &=, and)
ATOMIC64_OPS(or, |=, or)
ATOMIC64_OPS(xor, ^=, xor)
#define atomic64_fetch_and_relaxed atomic64_fetch_and_relaxed
#define atomic64_fetch_or_relaxed atomic64_fetch_or_relaxed
#define atomic64_fetch_xor_relaxed atomic64_fetch_xor_relaxed
#undef ATOMIC64_OPS
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP
/*
* atomic64_sub_if_positive - conditionally subtract integer from atomic
* variable
* @i: integer value to subtract
* @v: pointer of type atomic64_t
*
* Atomically test @v and subtract @i if @v is greater or equal than @i.
* The function returns the old value of @v minus @i.
*/
static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
{
long result;
smp_mb__before_llsc();
if (kernel_uses_llsc) {
long temp;
__asm__ __volatile__(
" .set "MIPS_ISA_LEVEL" \n"
"1: lld %1, %2 # atomic64_sub_if_positive\n"
" dsubu %0, %1, %3 \n"
" move %1, %0 \n"
" bltz %0, 1f \n"
" scd %1, %2 \n"
"\t" __scbeqz " %1, 1b \n"
"1: \n"
" .set mips0 \n"
: "=&r" (result), "=&r" (temp),
"+" GCC_OFF_SMALL_ASM() (v->counter)
: "Ir" (i));
} else {
unsigned long flags;
raw_local_irq_save(flags);
result = v->counter;
result -= i;
if (result >= 0)
v->counter = result;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return result;
}
#define atomic64_cmpxchg(v, o, n) \
((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
#define atomic64_xchg(v, new) (xchg(&((v)->counter), (new)))
/*
* atomic64_dec_if_positive - decrement by 1 if old value positive
* @v: pointer of type atomic64_t
*/
#define atomic64_dec_if_positive(v) atomic64_sub_if_positive(1, v)
#endif /* CONFIG_64BIT */
#endif /* _ASM_ATOMIC_H */