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//==========================================================================

//

//      devs/wallclock/sh3.cxx

//

//      SH3 RTC module driver.

//

//==========================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

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//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):     jskov

// Contributors:  jskov

// Date:          2000-03-17

// Purpose:       Wallclock driver for SH3 CPU RTC module

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include <pkgconf/wallclock.h>          // Wallclock device config

#include <cyg/hal/hal_io.h>             // IO macros

#include <cyg/infra/cyg_type.h>         // Common type definitions and support

#include <cyg/io/wallclock.hxx>         // The WallClock API

#include <cyg/io/wallclock/wallclock.inl> // Helpers

#include <cyg/hal/sh_regs.h>            // RTC register definitions

#include <cyg/infra/diag.h>             // For debugging

//-----------------------------------------------------------------------------

// Functions for setting and getting the hardware clock counters

// Year must be last two digits of "western calendar year". Leap year when

// divisible by four.

static void

set_sh3_hwclock(cyg_uint32 year, cyg_uint32 month, cyg_uint32 mday,

                cyg_uint32 hour, cyg_uint32 minute, cyg_uint32 second)

{

    // Stop RTC

    HAL_WRITE_UINT8(CYGARC_REG_RCR2, CYGARC_REG_RCR2_RESET);

    // Program it

    HAL_WRITE_UINT8(CYGARC_REG_RYRCNT,  TO_BCD(year));

    HAL_WRITE_UINT8(CYGARC_REG_RMONCNT, TO_BCD(month));

    HAL_WRITE_UINT8(CYGARC_REG_RDAYCNT, TO_BCD(mday));

    HAL_WRITE_UINT8(CYGARC_REG_RHRCNT,  TO_BCD(hour));

    HAL_WRITE_UINT8(CYGARC_REG_RMINCNT, TO_BCD(minute));

    HAL_WRITE_UINT8(CYGARC_REG_RSECCNT, TO_BCD(second));

    // Start RTC

    HAL_WRITE_UINT8(CYGARC_REG_RCR1, CYGARC_REG_RCR1_CIE);

    HAL_WRITE_UINT8(CYGARC_REG_RCR2,

                    CYGARC_REG_RCR2_RTCEN | CYGARC_REG_RCR2_START);

}

static void

get_sh3_hwclock(cyg_uint32* year, cyg_uint32* month, cyg_uint32* mday,

                cyg_uint32* hour, cyg_uint32* minute, cyg_uint32* second)

{

    cyg_uint8 tmp;

    do {

        // Clear carry flag

        HAL_WRITE_UINT8(CYGARC_REG_RCR1, 0);

        // Read time

        HAL_READ_UINT8(CYGARC_REG_RYRCNT, tmp);

        *year = TO_DEC(tmp);

        HAL_READ_UINT8(CYGARC_REG_RMONCNT, tmp);

        *month = TO_DEC(tmp);

        HAL_READ_UINT8(CYGARC_REG_RDAYCNT, tmp);

        *mday = TO_DEC(tmp);

        HAL_READ_UINT8(CYGARC_REG_RHRCNT, tmp);

        *hour = TO_DEC(tmp);

        HAL_READ_UINT8(CYGARC_REG_RMINCNT, tmp);

        *minute = TO_DEC(tmp);

        HAL_READ_UINT8(CYGARC_REG_RSECCNT, tmp);

        *second = TO_DEC(tmp);

        // Read carry flag

        HAL_READ_UINT8(CYGARC_REG_RCR1, tmp);

    } while (CYGARC_REG_RCR1_CF & tmp); // loop if carry set

}

//-----------------------------------------------------------------------------

// Functions required for the hardware-driver API.

// Returns the number of seconds elapsed since 1970-01-01 00:00:00.

cyg_uint32

Cyg_WallClock::get_hw_seconds(void)

{

    cyg_uint32 year, month, mday, hour, minute, second;

    get_sh3_hwclock(&year, &month, &mday, &hour, &minute, &second);

#if 0

    // This will cause the test to eventually fail due to these printouts

    // causing timer interrupts to be lost...

    diag_printf("year %02d\n", year);

    diag_printf("month %02d\n", month);

    diag_printf("mday %02d\n", mday);

    diag_printf("hour %02d\n", hour);

    diag_printf("minute %02d\n", minute);

    diag_printf("second %02d\n", second);

#endif

#ifndef CYGSEM_WALLCLOCK_SET_GET_MODE

    // We know what we initialized the hardware for : 1970, so by doing this

    // the returned time should be OK for 30 years uptime.

    year += 1900;

#else

    // Need to use sliding window or similar to figure out what the

    // century should be... Patent issue is unclear, and since there's

    // no battery backup of the clock, there's little point in

    // investigating.

# error "Need some magic here to figure out century counter"

#endif

    cyg_uint32 now = _simple_mktime(year, month, mday, hour, minute, second);

    return now;

}

#ifndef CYGSEM_WALLCLOCK_SET_GET_MODE

void

Cyg_WallClock::init_hw_seconds(void)

{

    // This is our base: 1970-01-01 00:00:00

    // Set the HW clock - if for nothing else, just to be sure it's in a

    // legal range. Any arbitrary base could be used.

    // After this the hardware clock is only read.

    set_sh3_hwclock(70,1,1,0,0,0);

}

#endif // CYGSEM_WALLCLOCK_SET_GET_MODE

//-----------------------------------------------------------------------------

// End of devs/wallclock/sh3.cxx