1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
8 #include <asm/cmpxchg.h>
9 #include <asm/loongarch.h>
12 * The "address" (in fact, offset from $r21) of a per-CPU variable is close to
13 * the loading address of main kernel image, but far from where the modules are
14 * loaded. Tell the compiler this fact when using explicit relocs.
16 #if defined(MODULE) && defined(CONFIG_AS_HAS_EXPLICIT_RELOCS)
17 # if __has_attribute(model)
18 # define PER_CPU_ATTRIBUTES __attribute__((model("extreme")))
20 # error compiler support for the model attribute is necessary when a recent assembler is used
24 /* Use r21 for fast access */
25 register unsigned long __my_cpu_offset __asm__("$r21");
27 static inline void set_my_cpu_offset(unsigned long off)
29 __my_cpu_offset = off;
30 csr_write64(off, PERCPU_BASE_KS);
32 #define __my_cpu_offset __my_cpu_offset
34 #define PERCPU_OP(op, asm_op, c_op) \
35 static __always_inline unsigned long __percpu_##op(void *ptr, \
36 unsigned long val, int size) \
42 __asm__ __volatile__( \
43 "am"#asm_op".w" " %[ret], %[val], %[ptr] \n" \
44 : [ret] "=&r" (ret), [ptr] "+ZB"(*(u32 *)ptr) \
48 __asm__ __volatile__( \
49 "am"#asm_op".d" " %[ret], %[val], %[ptr] \n" \
50 : [ret] "=&r" (ret), [ptr] "+ZB"(*(u64 *)ptr) \
58 return ret c_op val; \
61 PERCPU_OP(add, add, +)
62 PERCPU_OP(and, and, &)
66 static __always_inline unsigned long __percpu_read(void __percpu *ptr, int size)
72 __asm__ __volatile__ ("ldx.b %[ret], $r21, %[ptr] \n"
78 __asm__ __volatile__ ("ldx.h %[ret], $r21, %[ptr] \n"
84 __asm__ __volatile__ ("ldx.w %[ret], $r21, %[ptr] \n"
90 __asm__ __volatile__ ("ldx.d %[ret], $r21, %[ptr] \n"
103 static __always_inline void __percpu_write(void __percpu *ptr, unsigned long val, int size)
107 __asm__ __volatile__("stx.b %[val], $r21, %[ptr] \n"
109 : [val] "r" (val), [ptr] "r" (ptr)
113 __asm__ __volatile__("stx.h %[val], $r21, %[ptr] \n"
115 : [val] "r" (val), [ptr] "r" (ptr)
119 __asm__ __volatile__("stx.w %[val], $r21, %[ptr] \n"
121 : [val] "r" (val), [ptr] "r" (ptr)
125 __asm__ __volatile__("stx.d %[val], $r21, %[ptr] \n"
127 : [val] "r" (val), [ptr] "r" (ptr)
135 static __always_inline unsigned long __percpu_xchg(void *ptr, unsigned long val, int size)
140 return __xchg_small((volatile void *)ptr, val, size);
143 return __xchg_asm("amswap.w", (volatile u32 *)ptr, (u32)val);
146 return __xchg_asm("amswap.d", (volatile u64 *)ptr, (u64)val);
155 /* this_cpu_cmpxchg */
156 #define _protect_cmpxchg_local(pcp, o, n) \
158 typeof(*raw_cpu_ptr(&(pcp))) __ret; \
159 preempt_disable_notrace(); \
160 __ret = cmpxchg_local(raw_cpu_ptr(&(pcp)), o, n); \
161 preempt_enable_notrace(); \
165 #define _percpu_read(pcp) \
167 typeof(pcp) __retval; \
168 __retval = (typeof(pcp))__percpu_read(&(pcp), sizeof(pcp)); \
172 #define _percpu_write(pcp, val) \
174 __percpu_write(&(pcp), (unsigned long)(val), sizeof(pcp)); \
177 #define _pcp_protect(operation, pcp, val) \
179 typeof(pcp) __retval; \
180 preempt_disable_notrace(); \
181 __retval = (typeof(pcp))operation(raw_cpu_ptr(&(pcp)), \
182 (val), sizeof(pcp)); \
183 preempt_enable_notrace(); \
187 #define _percpu_add(pcp, val) \
188 _pcp_protect(__percpu_add, pcp, val)
190 #define _percpu_add_return(pcp, val) _percpu_add(pcp, val)
192 #define _percpu_and(pcp, val) \
193 _pcp_protect(__percpu_and, pcp, val)
195 #define _percpu_or(pcp, val) \
196 _pcp_protect(__percpu_or, pcp, val)
198 #define _percpu_xchg(pcp, val) ((typeof(pcp)) \
199 _pcp_protect(__percpu_xchg, pcp, (unsigned long)(val)))
201 #define this_cpu_add_4(pcp, val) _percpu_add(pcp, val)
202 #define this_cpu_add_8(pcp, val) _percpu_add(pcp, val)
204 #define this_cpu_add_return_4(pcp, val) _percpu_add_return(pcp, val)
205 #define this_cpu_add_return_8(pcp, val) _percpu_add_return(pcp, val)
207 #define this_cpu_and_4(pcp, val) _percpu_and(pcp, val)
208 #define this_cpu_and_8(pcp, val) _percpu_and(pcp, val)
210 #define this_cpu_or_4(pcp, val) _percpu_or(pcp, val)
211 #define this_cpu_or_8(pcp, val) _percpu_or(pcp, val)
213 #define this_cpu_read_1(pcp) _percpu_read(pcp)
214 #define this_cpu_read_2(pcp) _percpu_read(pcp)
215 #define this_cpu_read_4(pcp) _percpu_read(pcp)
216 #define this_cpu_read_8(pcp) _percpu_read(pcp)
218 #define this_cpu_write_1(pcp, val) _percpu_write(pcp, val)
219 #define this_cpu_write_2(pcp, val) _percpu_write(pcp, val)
220 #define this_cpu_write_4(pcp, val) _percpu_write(pcp, val)
221 #define this_cpu_write_8(pcp, val) _percpu_write(pcp, val)
223 #define this_cpu_xchg_1(pcp, val) _percpu_xchg(pcp, val)
224 #define this_cpu_xchg_2(pcp, val) _percpu_xchg(pcp, val)
225 #define this_cpu_xchg_4(pcp, val) _percpu_xchg(pcp, val)
226 #define this_cpu_xchg_8(pcp, val) _percpu_xchg(pcp, val)
228 #define this_cpu_cmpxchg_1(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
229 #define this_cpu_cmpxchg_2(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
230 #define this_cpu_cmpxchg_4(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
231 #define this_cpu_cmpxchg_8(ptr, o, n) _protect_cmpxchg_local(ptr, o, n)
233 #include <asm-generic/percpu.h>
235 #endif /* __ASM_PERCPU_H */