include/arch/riscv/sel4runtime/thread_arch.h

/*
 * Copyright 2019, Data61
 * Commonwealth Scientific and Industrial Research Organisation (CSIRO)
 * ABN 41 687 119 230.
 *
 * This software may be distributed and modified according to the terms of
 * the BSD 2-Clause license. Note that NO WARRANTY is provided.
 * See "LICENSE_BSD2.txt" for details.
 *
 * @TAG(DATA61_BSD)
 */
#include <sel4runtime/stdint.h>

static inline sel4runtime_uintptr_t sel4runtime_read_tp(void)
{
#ifdef __clang__
    sel4runtime_uintptr_t reg;
    __asm__ __volatile__("or %0, tp, x0" : "=r"(reg));
#else
    register sel4runtime_uintptr_t reg __asm__("tp");
#endif
    return reg;
}

static inline void sel4runtime_write_tp(sel4runtime_uintptr_t reg)
{
    __asm__ __volatile__("or tp, %0, x0" :: "r"(reg));
}

/*
 * Obtain the value of the TLS base for the current thread.
 */
static inline sel4runtime_uintptr_t sel4runtime_get_tls_base(void)
{
    return sel4runtime_read_tp();
}

/*
 * Set the value of the TLS base for the current thread.
 */
static inline void sel4runtime_set_tls_base(sel4runtime_uintptr_t tls_base)
{
    sel4runtime_write_tp(tls_base);
}

#define TLS_ABOVE_TP