source: rtems/c/src/lib/libbsp/powerpc/gen83xx/startup/bspstart.c @ bbbb8f0

/**
 * @file
 *
 * @ingroup mpc83xx
 *
 * @brief Source for BSP startup code.
 */

/*
 * Copyright (c) 2008
 * Embedded Brains GmbH
 * Obere Lagerstr. 30
 * D-82178 Puchheim
 * Germany
 * rtems@embedded-brains.de
 *
 * The license and distribution terms for this file may be found in the file
 * LICENSE in this distribution or at http://www.rtems.com/license/LICENSE.
 *
 * $Id$
 */

#include <string.h>

#include <rtems/libio.h>
#include <rtems/libcsupport.h>
#include <rtems/score/thread.h>

#include <libcpu/powerpc-utility.h>
#include <libcpu/raw_exception.h>

#include <bsp.h>
#include <bsp/bootcard.h>
#include <bsp/irq-generic.h>
#include <bsp/ppc_exc_bspsupp.h>

#ifdef HAS_UBOOT

/*
 * We want this in the data section, because the startup code clears the BSS
 * section after the initialization of the board info.
 */
bd_t mpc83xx_uboot_board_info = { .bi_baudrate = 123 };

/* Size in words */
const size_t mpc83xx_uboot_board_info_size = (sizeof( bd_t) + 3) / 4;

#endif /* HAS_UBOOT */

/* Configuration parameters for console driver, ... */
unsigned int BSP_bus_frequency;

/* Configuration parameters for clock driver, ... */
uint32_t bsp_clicks_per_usec;

/* Default decrementer exception handler */
static int mpc83xx_decrementer_exception_handler( BSP_Exception_frame *frame, unsigned number)
{
        ppc_set_decrementer_register( UINT32_MAX);

        return 0;
}

void BSP_panic( char *s)
{
        rtems_interrupt_level level;

        rtems_interrupt_disable( level);

        printk( "%s PANIC %s\n", _RTEMS_version, s);

        while (1) {
                /* Do nothing */
        }
}

void _BSP_Fatal_error( unsigned n)
{
        rtems_interrupt_level level;

        rtems_interrupt_disable( level);

        printk( "%s PANIC ERROR %u\n", _RTEMS_version, n);

        while (1) {
                /* Do nothing */
        }
}

void bsp_pretasking_hook( void)
{
        /* Do noting */
}

void bsp_get_work_area( void **work_area_start, size_t *work_area_size, void **heap_start, size_t *heap_size)
{
#ifdef HAS_UBOOT
        char *ram_end = (char *) mpc83xx_uboot_board_info.bi_memstart + mpc83xx_uboot_board_info.bi_memsize;
#else /* HAS_UBOOT */
        char *ram_end = bsp_ram_end;
#endif /* HAS_UBOOT */

        *work_area_start = bsp_work_area_start;
        *work_area_size = ram_end - bsp_work_area_start;
        *heap_start = BSP_BOOTCARD_HEAP_USES_WORK_AREA;
        *heap_size = BSP_BOOTCARD_HEAP_SIZE_DEFAULT;
}

void bsp_start( void)
{
        rtems_status_code sc = RTEMS_SUCCESSFUL;
        int rv = 0;

        ppc_cpu_id_t myCpu;
        ppc_cpu_revision_t myCpuRevision;

        uint32_t interrupt_stack_start = (uint32_t) bsp_interrupt_stack_start;
        uint32_t interrupt_stack_size = (uint32_t) bsp_interrupt_stack_size;

        /*
         * Get CPU identification dynamically. Note that the get_ppc_cpu_type() function
         * store the result in global variables so that it can be used latter...
         */
        myCpu = get_ppc_cpu_type();
        myCpuRevision = get_ppc_cpu_revision();

        /* Basic CPU initialization */
        cpu_init();

        /*
         * Enable instruction and data caches. Do not force writethrough mode.
         */

#if INSTRUCTION_CACHE_ENABLE
        rtems_cache_enable_instruction();
#endif

#if DATA_CACHE_ENABLE
        rtems_cache_enable_data();
#endif

        /*
         * This is evaluated during runtime, so it should be ok to set it
         * before we initialize the drivers.
         */

        /* Initialize some device driver parameters */

#ifdef HAS_UBOOT
        BSP_bus_frequency = mpc83xx_uboot_board_info.bi_busfreq;
        bsp_clicks_per_usec = mpc83xx_uboot_board_info.bi_intfreq / 8000000;
#else /* HAS_UBOOT */
        BSP_bus_frequency = BSP_CLKIN_FRQ * BSP_SYSPLL_MF / BSP_SYSPLL_CKID;
        bsp_clicks_per_usec = BSP_bus_frequency / 1000000;
#endif /* HAS_UBOOT */

        /* Initialize exception handler */
        ppc_exc_initialize(
                PPC_INTERRUPT_DISABLE_MASK_DEFAULT,
                interrupt_stack_start,
                interrupt_stack_size
        );

        /* Install default handler for the decrementer exception */
        rv = ppc_exc_set_handler( ASM_DEC_VECTOR, mpc83xx_decrementer_exception_handler);
        if (rv < 0) {
                BSP_panic( "Cannot install decrementer exception handler!\n");
        }

        /* Initalize interrupt support */
        sc = bsp_interrupt_initialize();
        if (sc != RTEMS_SUCCESSFUL) {
                BSP_panic( "Cannot intitialize interrupt support\n");
        }

#ifdef SHOW_MORE_INIT_SETTINGS
        printk("Exit from bspstart\n");
#endif
}

/**
 * @brief Idle thread body.
 *
 * Replaces the one in c/src/exec/score/src/threadidlebody.c
 * The MSR[POW] bit is set to put the CPU into the low power mode
 * defined in HID0.  HID0 is set during starup in start.S.
 */
Thread _Thread_Idle_body( uint32_t ignored)
{

        while (1) {
                asm volatile (
                        "mfmsr 3;"
                        "oris 3, 3, 4;"
                        "sync;"
                        "mtmsr 3;"
                        "isync;"
                        "ori 3, 3, 0;"
                        "ori 3, 3, 0"
                );
        }

        return NULL;
}

void bsp_cleanup( void)
{
#ifdef MPC8313ERDB

        /* Set Reset Protection Register (RPR) to "RSTE" */
        mpc83xx.res.rpr = 0x52535445;

        /*
         * Wait for Control Register Enabled in the
         * Reset Control Enable Register (RCER).
         */
        while (mpc83xx.res.rcer != 0x00000001) {
                /* Wait */
        }

        /* Set Software Hard Reset in the Reset Control Register (RCR) */
        mpc83xx.res.rcr = 0x00000002;

#else /* MPC8313ERDB */

        /* Do nothing */

#endif /* MPC8313ERDB */
}