incubator-nuttx/arch/arm/include/tls.h

108 lines
4.0 KiB
C

/****************************************************************************
* arch/arm/include/tls.h
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __ARCH_ARM_INCLUDE_TLS_H
#define __ARCH_ARM_INCLUDE_TLS_H 1
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <nuttx/arch.h>
#include <nuttx/tls.h>
#ifdef CONFIG_TLS
/****************************************************************************
* Inline Functions
****************************************************************************/
/****************************************************************************
* Name: up_getsp
****************************************************************************/
/* I don't know if the builtin to get SP is enabled */
static inline uint32_t up_getsp(void)
{
uint32_t sp;
__asm__
(
"\tmov %0, sp\n\t"
: "=r"(sp)
);
return sp;
}
/****************************************************************************
* Name: up_tls_info
*
* Description:
* Return the TLS information structure for the currently executing thread.
* When TLS is enabled, up_createstack() will align allocated stacks to
* the TLS_STACK_ALIGN value. An instance of the following structure will
* be implicitly positioned at the "lower" end of the stack. Assuming a
* "push down" stack, this is at the "far" end of the stack (and can be
* clobbered if the stack overflows).
*
* If an MCU has a "push up" then that TLS structure will lie at the top
* of the stack and stack allocation and initialization logic must take
* care to preserve this structure content.
*
* The stack memory is fully accessible to user mode threads.
*
* Input Parameters:
* None
*
* Returned Value:
* A pointer to TLS info structure at the beginning of the STACK memory
* allocation. This is essentially an application of the TLS_INFO(sp)
* macro and has a platform dependency only in the manner in which the
* stack pointer (sp) is obtained and interpreted.
*
****************************************************************************/
static inline FAR struct tls_info_s *up_tls_info(void)
{
DEBUGASSERT(!up_interrupt_context());
return TLS_INFO((uintptr_t)up_getsp());
}
#endif /* CONFIG_TLS */
#endif /* __ARCH_ARM_INCLUDE_TLS_H */