zephyr/arch/xtensa/core/tls.c

48 lines
1.3 KiB
C

/*
* Copyright (c) 2020 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/kernel.h>
#include <zephyr/kernel_structs.h>
#include <kernel_internal.h>
#include <kernel_tls.h>
#include <zephyr/app_memory/app_memdomain.h>
#include <zephyr/sys/util.h>
#if XCHAL_HAVE_THREADPTR == 0
#error SoC does not support THREADPTR for thread local storage.
#endif
size_t arch_tls_stack_setup(struct k_thread *new_thread, char *stack_ptr)
{
/*
* TLS area has some data fields following by
* thread data and bss. These fields are supposed to be
* used by toolchain and OS TLS code to aid in locating
* the TLS data/bss. Zephyr currently has no use for
* this so we can simply skip these. However, since GCC
* is generating code assuming these fields are there,
* we simply skip them when setting the TLS pointer.
*/
/*
* Since we are populating things backwards,
* setup the TLS data/bss area first.
*/
stack_ptr -= z_tls_data_size();
z_tls_copy(stack_ptr);
/* Skip two pointers due to toolchain */
stack_ptr -= sizeof(uintptr_t) * 2;
/*
* Set thread TLS pointer which is used in
* context switch to point to TLS area.
*/
new_thread->tls = POINTER_TO_UINT(stack_ptr);
return (z_tls_data_size() + (sizeof(uintptr_t) * 2));
}