source: trunk/libs/newlib/src/libgloss/aarch64/cpu-init/rdimon-aem-el3.S @ 675

/* Copyright (c) 2009, 2010, 2011, 2012 ARM Ltd.  All rights reserved.

 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. The name of the company may not be used to endorse or promote
    products derived from this software without specific prior written
    permission.

 THIS SOFTWARE IS PROVIDED BY ARM LTD ``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 ARM LTD 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. */

#include "newlib.h"
#include "svc.h"

/* ANSI concatenation macros.  */
#define CONCAT(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b

#ifdef __USER_LABEL_PREFIX__
#define FUNCTION( name ) CONCAT (__USER_LABEL_PREFIX__, name)
#else
#error __USER_LABEL_PREFIX is not defined
#endif


        .text
        .align 2
_init_vectors:
        /* Installs a table of exception vectors to catch and handle all
           exceptions by terminating the process with a diagnostic.  */
        adr     x0, vectors
        msr     vbar_el3, x0
        msr     vbar_el2, x0
        msr     vbar_el1, x0
        ret

curr_sp0_sync:
curr_sp0_irq:
curr_sp0_fiq:
curr_sp0_serror:
curr_spx_sync:
curr_spx_irq:
curr_spx_fiq:
curr_spx_serror:
lower_a64_sync:
lower_a64_irq:
lower_a64_fiq:
lower_a64_serror:
lower_a32_sync:
lower_a32_irq:
lower_a32_fiq:
lower_a32_serror:
        mov     x0, 2
        adr     x1, .LC3
        mov     x2, 26
        bl      FUNCTION (write)
        mov     x0,  126
        b       FUNCTION (exit)         /* Cannot return.  */
.LC3:
        .string "Terminated by exception.\n"

        .macro  ventry  label
        .align  7
        b       \label
        .endm

        /* AArch64 Exception Model -- 3.5.5 Exception Vectors.  */

        .align  12
vectors:
        /* Current EL with SP0.  */
        ventry  curr_sp0_sync           /* Synchronous  */
        ventry  curr_sp0_irq            /* Irq/vIRQ  */
        ventry  curr_sp0_fiq            /* Fiq/vFIQ  */
        ventry  curr_sp0_serror         /* SError/VSError  */

        /* Current EL with SPx.  */
        ventry  curr_spx_sync           /* Synchronous  */
        ventry  curr_spx_irq            /* IRQ/vIRQ  */
        ventry  curr_spx_fiq            /* FIQ/vFIQ  */
        ventry  curr_spx_serror         /* SError/VSError  */

        /* Lower EL using AArch64.  */
        ventry  lower_a64_sync          /* Synchronous  */
        ventry  lower_a64_irq           /* IRQ/vIRQ  */
        ventry  lower_a64_fiq           /* FIQ/vFIQ  */
        ventry  lower_a64_serror        /* SError/VSError  */

        /* Lower EL using AArch32.  */
        ventry  lower_a32_sync          /* Synchronous  */
        ventry  lower_a32_irq           /* IRQ/vIRQ  */
        ventry  lower_a32_fiq           /* FIQ/vFIQ  */
        ventry  lower_a32_serror        /* SError/VSError  */


        .text
        .align 2
_flat_map:
        /* Page table setup (identity mapping).  */
        adrp    x0, ttb
        add     x0, x0, :lo12:ttb
        msr     ttbr0_el3, x0
        adr     x1, .                           /* phys address */
        bic     x1, x1, #(1 << 30) - 1          /* 1GB block alignment */
        add     x2, x0, x1, lsr #(30 - 3)       /* offset in level 1 page
                                                   table */
        mov     x3, #0x401                      /* page table attributes
                                                   (AF, block) */
        orr     x1, x1, x3
        mov     x3, #(1 << 30)                  /* 1GB block */
        str     x1, [x2], #8                    /* 1st GB */
        add     x1, x1, x3
        str     x1, [x2]                        /* 2nd GB */

        /* Setup/enable the MMU.  */

        /* RES1, RES1, 40-bit PA, 39-bit VA, inner/outer cacheable WB */
        ldr     x0, =(1 << 31) | (1 << 23) | (2 << 16) | 25 | (3 << 10) | (3 << 8)
        msr     tcr_el3, x0

        mov     x0, #0xee                       /* Inner/outer cacheable WB */
        msr     mair_el3, x0
        isb

        mrs     x0, sctlr_el3
        ldr     x1, =0x100d                     /* bits I(12) SA(3) C(2) M(0) */
        bic     x0, x0, #(1 << 1)               /* clear bit A(1) */
        bic     x0, x0, #(1 << 19)              /* clear WXN */
        orr     x0, x0, x1                      /* set bits */

        dsb     sy
        msr     sctlr_el3, x0
        isb
        ret

        .data
        .align  12
ttb:
        .space  4096, 0


        .text
        .align 2
        .global FUNCTION (_cpu_init_hook)
        .type   FUNCTION (_cpu_init_hook), %function
FUNCTION (_cpu_init_hook):
        sub     sp, sp, #16
        str     x30, [sp, xzr]
        bl      _init_vectors
        bl      _flat_map
        ldr     x30, [sp, xzr]
        add     sp, sp, #16
        ret
        .size   FUNCTION (_cpu_init_hook), .-FUNCTION (_cpu_init_hook)