zephyr/arch/x86/include/asm_inline_gcc.h

144 lines
2.9 KiB
C

/* Intel x86 GCC specific kernel inline assembler functions and macros */
/*
* Copyright (c) 2015, Wind River Systems, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _ASM_INLINE_GCC_H
#define _ASM_INLINE_GCC_H
#ifdef __cplusplus
extern "C" {
#endif
/*
* The file must not be included directly
* Include asm_inline.h instead
*/
#ifndef _ASMLANGUAGE
/**
*
* @brief Return the current value of the EFLAGS register
*
* @return the EFLAGS register.
*/
static inline unsigned int EflagsGet(void)
{
unsigned int eflags; /* EFLAGS register contents */
__asm__ volatile(
"pushfl;\n\t"
"popl %0;\n\t"
: "=r"(eflags)
: );
return eflags;
}
#ifdef CONFIG_FP_SHARING
/**
*
* @brief Disallow use of floating point capabilities
*
* This routine sets CR0[TS] to 1, which disallows the use of FP instructions
* by the currently executing thread.
*
* @return N/A
*/
static inline void _FpAccessDisable(void)
{
void *tempReg;
__asm__ volatile(
"movl %%cr0, %0;\n\t"
"orl $0x8, %0;\n\t"
"movl %0, %%cr0;\n\t"
: "=r"(tempReg)
:
: "memory");
}
/**
*
* @brief Save non-integer context information
*
* This routine saves the system's "live" non-integer context into the
* specified area. If the specified task or fiber supports SSE then
* x87/MMX/SSEx thread info is saved, otherwise only x87/MMX thread is saved.
* Function is invoked by _FpCtxSave(struct tcs *tcs)
*
* @return N/A
*/
static inline void _do_fp_ctx_save(int flags, void *preemp_float_reg)
{
#ifdef CONFIG_SSE
if (flags) {
__asm__ volatile("fxsave (%0);\n\t"
:
: "r"(preemp_float_reg)
: "memory");
} else
#else
ARG_UNUSED(flags);
#endif /* CONFIG_SSE */
{
__asm__ volatile("fnsave (%0);\n\t"
:
: "r"(preemp_float_reg)
: "memory");
}
}
/**
*
* @brief Initialize non-integer context information
*
* This routine initializes the system's "live" non-integer context.
* Function is invoked by _FpCtxInit(struct tcs *tcs)
*
* @return N/A
*/
static inline void _do_fp_ctx_init(int flags)
{
/* initialize x87 FPU */
__asm__ volatile("fninit\n\t");
#ifdef CONFIG_SSE
if (flags) {
/* initialize SSE (since thread uses it) */
__asm__ volatile("ldmxcsr _sse_mxcsr_default_value\n\t");
}
#else
ARG_UNUSED(flags);
#endif /* CONFIG_SSE */
}
#endif /* CONFIG_FP_SHARING */
#endif /* _ASMLANGUAGE */
#ifdef __cplusplus
}
#endif
#endif /* _ASM_INLINE_GCC_H */