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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#ifndef __ASM_PERCPU_H
#define __ASM_PERCPU_H
#include <asm/cmpxchg.h>
#include <asm/loongarch.h>
/*
* The "address" (in fact, offset from $r21) of a per-CPU variable is close to
* the loading address of main kernel image, but far from where the modules are
* loaded. Tell the compiler this fact when using explicit relocs.
*/
#if defined(MODULE) && defined(CONFIG_AS_HAS_EXPLICIT_RELOCS)
# if __has_attribute(model)
# define PER_CPU_ATTRIBUTES __attribute__((model("extreme")))
# else
# error compiler support for the model attribute is necessary when a recent assembler is used
# endif
#endif
/* Use r21 for fast access */
register unsigned long __my_cpu_offset __asm__("$r21");
static inline void set_my_cpu_offset(unsigned long off)
{
__my_cpu_offset = off;
csr_write64(off, PERCPU_BASE_KS);
}
#define __my_cpu_offset \
({ \
__asm__ __volatile__("":"+r"(__my_cpu_offset)); \
__my_cpu_offset; \
})
#define PERCPU_OP(op, asm_op, c_op) \
static __always_inline unsigned long __percpu_##op(void *ptr, \
unsigned long val, int size) \
{ \
unsigned long ret; \
\
switch (size) { \
case 4: \
__asm__ __volatile__( \
"am"#asm_op".w" " %[ret], %[val], %[ptr] \n" \
: [ret] "=&r" (ret), [ptr] "+ZB"(*(u32 *)ptr) \
: [val] "r" (val)); \
break; \
case 8: \
__asm__ __volatile__( \
"am"#asm_op".d" " %[ret], %[val], %[ptr] \n" \
: [ret] "=&r" (ret), [ptr] "+ZB"(*(u64 *)ptr) \
: [val] "r" (val)); \
break; \
default: \
ret = 0; \
BUILD_BUG(); \
} \
\
return ret c_op val; \
}
PERCPU_OP(add, add, +)
PERCPU_OP(and, and, &)
PERCPU_OP(or, or, |)
#undef PERCPU_OP
static __always_inline unsigned long __percpu_read(void __percpu *ptr, int size)
{
unsigned long ret;
switch (size) {
case 1:
__asm__ __volatile__ ("ldx.b %[ret], $r21, %[ptr] \n"
: [ret] "=&r"(ret)
: [ptr] "r"(ptr)
: "memory");
break;
case 2:
__asm__ __volatile__ ("ldx.h %[ret], $r21, %[ptr] \n"
: [ret] "=&r"(ret)
: [ptr] "r"(ptr)
: "memory");
break;
case 4:
__asm__ __volatile__ ("ldx.w %[ret], $r21, %[ptr] \n"
: [ret] "=&r"(ret)
: [ptr] "r"(ptr)
: "memory");
break;
case 8:
__asm__ __volatile__ ("ldx.d %[ret], $r21, %[ptr] \n"
: [ret] "=&r"(ret)
: [ptr] "r"(ptr)
: "memory");
break;
default:
ret = 0;
BUILD_BUG();
}
return ret;
}
static __always_inline void __percpu_write(void __percpu *ptr, unsigned long val, int size)
{
switch (size) {
case 1:
__asm__ __volatile__("stx.b %[val], $r21, %[ptr] \n"
:
: [val] "r" (val), [ptr] "r" (ptr)
: "memory");
break;
case 2:
__asm__ __volatile__("stx.h %[val], $r21, %[ptr] \n"
:
: [val] "r" (val), [ptr] "r" (ptr)
: "memory");
break;
case 4:
__asm__ __volatile__("stx.w %[val], $r21, %[ptr] \n"
:
: [val] "r" (val), [ptr] "r" (ptr)
: "memory");
break;
case 8:
__asm__ __volatile__("stx.d %[val], $r21, %[ptr] \n"
:
: [val] "r" (val), [ptr] "r" (ptr)
: "memory");
break;
default:
BUILD_BUG();
}
}
static __always_inline unsigned long __percpu_xchg(void *ptr, unsigned long val, int size)
{
switch (size) {
case 1:
case 2:
return __xchg_small((volatile void *)ptr, val, size);
case 4:
return __xchg_asm("amswap.w", (volatile u32 *)ptr, (u32)val);
case 8:
return __xchg_asm("amswap.d", (volatile u64 *)ptr, (u64)val);
default:
BUILD_BUG();
}
return 0;
}
/* this_cpu_cmpxchg */
#define _protect_cmpxchg_local(pcp, o, n) \
({ \
typeof(*raw_cpu_ptr(&(pcp))) __ret; \
preempt_disable_notrace(); \
__ret = cmpxchg_local(raw_cpu_ptr(&(pcp)), o, n); \
preempt_enable_notrace(); \
__ret; \
})
#define _percpu_read(pcp) \
({ \
typeof(pcp) __retval; \
__retval = (typeof(pcp))__percpu_read(&(pcp), sizeof(pcp)); \
__retval; \
})
#define _percpu_write(pcp, val) \
do { \
__percpu_write(&(pcp), (unsigned long)(val), sizeof(pcp)); \
} while (0) \
#define _pcp_protect(operation, pcp, val) \
({ \
typeof(pcp) __retval; \
preempt_disable_notrace(); \
__retval = (typeof(pcp))operation(raw_cpu_ptr(&(pcp)), \
(val), sizeof(pcp)); \
preempt_enable_notrace(); \
__retval; \
})
#define _percpu_add(pcp, val) \
_pcp_protect(__percpu_add, pcp, val)
#define _percpu_add_return(pcp, val) _percpu_add(pcp, val)
#define _percpu_and(pcp, val) \
_pcp_protect(__percpu_and, pcp, val)
#define _percpu_or(pcp, val) \
_pcp_protect(__percpu_or, pcp, val)
#define _percpu_xchg(pcp, val) ((typeof(pcp)) \
_pcp_protect(__percpu_xchg, pcp, (unsigned long)(val)))
#define this_cpu_add_4(pcp, val) _percpu_add(pcp, val)
#define this_cpu_add_8(pcp, val) _percpu_add(pcp, val)
#define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val)
#define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val)
#define this_cpu_and_4(pcp, val) _percpu_and(pcp, val)
#define this_cpu_and_8(pcp, val) _percpu_and(pcp, val)
#define this_cpu_or_4(pcp, val) _percpu_or(pcp, val)
#define this_cpu_or_8(pcp, val) _percpu_or(pcp, val)
#define this_cpu_read_1(pcp) _percpu_read(pcp)
#define this_cpu_read_2(pcp) _percpu_read(pcp)
#define this_cpu_read_4(pcp) _percpu_read(pcp)
#define this_cpu_read_8(pcp) _percpu_read(pcp)
#define this_cpu_write_1(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_2(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_4(pcp, val) _percpu_write(pcp, val)
#define this_cpu_write_8(pcp, val) _percpu_write(pcp, val)
#define this_cpu_xchg_1(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_2(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val)
#define this_cpu_cmpxchg_1(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
#define this_cpu_cmpxchg_2(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
#define this_cpu_cmpxchg_4(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
#define this_cpu_cmpxchg_8(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
#include <asm-generic/percpu.h>
#endif /* __ASM_PERCPU_H */
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