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/*

 *  Override _hardreset hook in BCC startup code in order to

 *  initialize CPU, stack pointer, GPTIMER and IRQMP.

 *

 *  This is only used when the test program runs in a simulated LEON3.

 *  In real hardware, these things are handled either by the boot PROM

 *  or by GRMON.

 */

#define STACKPTR        0x4001fff0

#define FREQ_MHZ        40

#define GPTIMER_BASE    0x80000300

#define GPTIMER_SCALER_RELOAD   0x04

#define IRQMP_BASE      0x80000200

#define IRQMP_ILEVEL    0x00

#define IRQMP_ICLEAR    0x0c

#define IRQMP_MASK      0x40

.seg    "text"

.global _hardreset

_hardreset:

    /* Reset CPU */

    flush

    set   0xc0, %g1

    mov   %g1,  %psr

    mov   2,    %g1

    mov   %g1,  %wim

    /* Enable instruction cache */

    set   0x00200003, %g1

    sta   %g1,  [%g0] 2

    /* Set up stack pointer */

    set   STACKPTR, %g1

    mov   %g1,  %fp

    sub   %g1,  96,  %sp

    /* Set GPTIMER scale factor for 50 MHz */

    set   GPTIMER_BASE, %g2

    set   FREQ_MHZ-1, %g1

    st    %g1,  [%g2+GPTIMER_SCALER_RELOAD]

    /* Reset IRQMP (some of its registers are not cleared during hard reset) */

    set   IRQMP_BASE, %g2

    st    %g0,  [%g2+IRQMP_ILEVEL]

    st    %g0,  [%g2+IRQMP_MASK]

    orn   %g0,  %g0,  %g1

    st    %g1,  [%g2+IRQMP_ICLEAR]

    /* Set up trap table and enable traps */

    set   _trap_table, %g1

    mov   %g1,  %tbr

    set   0xe0, %g1

    mov   %g1,  %psr

    /* Jump back to BCC startup code */

    set   _hardreset_real,  %g1

    jmp   %g1

    nop