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/*==========================================================================

//

//      timer_tc.c

//

//      HAL timer code using the Timer Counter

//

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

// ####ECOSGPLCOPYRIGHTBEGIN####

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

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

// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2010 Free Software Foundation, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later

// version.

//

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// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License

// along with eCos; if not, write to the Free Software Foundation, Inc.,

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

//

// As a special exception, if other files instantiate templates or use

// macros or inline functions from this file, or you compile this file

// and link it with other works to produce a work based on this file,

// this file does not by itself cause the resulting work to be covered by

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// must still be made available in accordance with section (3) of the GNU

// General Public License v2.

//

// This exception does not invalidate any other reasons why a work based

// on this file might be covered by the GNU General Public License.

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

// ####ECOSGPLCOPYRIGHTEND####

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

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

//

// Author(s):    gthomas

// Contributors: gthomas, jskov, nickg, tkoeller, jld

// Date:         2001-07-12

// Purpose:      HAL board support

// Description:  Implementations of HAL board interfaces

//

//####DESCRIPTIONEND####

//

//========================================================================*/

#include <pkgconf/hal.h>

#include <cyg/infra/cyg_type.h>         // base types

#include <cyg/infra/cyg_ass.h>          // assertion macros

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

#include <cyg/hal/hal_arch.h>           // Register state info

#include <cyg/hal/hal_intr.h>           // necessary?

#ifdef CYGFUN_HAL_ARM_AT91_PROFILE_TIMER

#include <cyg/hal/drv_api.h>            // CYG_ISR_HANDLED

#include <cyg/profile/profile.h>        // __profile_hit()

#endif

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

// Clock support

static cyg_uint32 _period;

void hal_clock_initialize(cyg_uint32 period)

{

    CYG_ADDRESS timer = AT91_TC+AT91_TC_TC0;

    CYG_ASSERT(period < 0x10000, "Invalid clock period");

    // Disable counter

    HAL_WRITE_UINT32(timer+AT91_TC_CCR, AT91_TC_CCR_CLKDIS);

    // Set registers

    HAL_WRITE_UINT32(timer+AT91_TC_CMR, AT91_TC_CMR_CPCTRG |        // Reset counter on CPC

                                        AT91_TC_CMR_CLKS_MCK32);    // 1 MHz

    HAL_WRITE_UINT32(timer+AT91_TC_RC, period);

    // Start timer

    HAL_WRITE_UINT32(timer+AT91_TC_CCR, AT91_TC_CCR_TRIG | AT91_TC_CCR_CLKEN);

    // Enable timer 0 interrupt    

    HAL_WRITE_UINT32(timer+AT91_TC_IER, AT91_TC_IER_CPC);

}

void hal_clock_reset(cyg_uint32 vector, cyg_uint32 period)

{

    CYG_ADDRESS timer = AT91_TC+AT91_TC_TC0;

    cyg_uint32 sr;

    CYG_ASSERT(period < 0x10000, "Invalid clock period");

    HAL_READ_UINT32(timer+AT91_TC_SR, sr);  // Clear interrupt

    if (period != _period) {

        hal_clock_initialize(period);

    }

    _period = period;

}

void hal_clock_read(cyg_uint32 *pvalue)

{

    CYG_ADDRESS timer = AT91_TC+AT91_TC_TC0;

    cyg_uint32 val;

    HAL_READ_UINT32(timer+AT91_TC_CV, val);

    *pvalue = val;

}

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

//

// Delay for some number of micro-seconds

//   Use timer #2 in MCLOCK/32 mode.

//

void hal_delay_us(cyg_int32 usecs)

{

    cyg_uint32 stat;

    cyg_uint64 ticks;

#if defined(CYGHWR_HAL_ARM_AT91_JTST)

    // TC2 is reserved for AD/DA. Use TC1 instead. 

    CYG_ADDRESS timer = AT91_TC+AT91_TC_TC1;

#else

    CYG_ADDRESS timer = AT91_TC+AT91_TC_TC2;

#endif

    // Calculate how many timer ticks the required number of

    // microseconds equate to. We do this calculation in 64 bit

    // arithmetic to avoid overflow.

    ticks = (((cyg_uint64)usecs) *

             ((cyg_uint64)CYGNUM_HAL_ARM_AT91_CLOCK_SPEED))/32000000LL;

    //    CYG_ASSERT(ticks < (1 << 16), "Timer overflow");

    if (ticks > (1 << 16))

      ticks = (1 << 16) - 1;

    if (ticks == 0)

      return;

    // Disable counter

    HAL_WRITE_UINT32(timer+AT91_TC_CCR, AT91_TC_CCR_CLKDIS);

    // Set registers

    HAL_WRITE_UINT32(timer+AT91_TC_CMR, AT91_TC_CMR_CLKS_MCK32);  // 1MHz

    HAL_WRITE_UINT32(timer+AT91_TC_RA, 0);

    HAL_WRITE_UINT32(timer+AT91_TC_RC, ticks);

    // Clear status flags

    HAL_READ_UINT32(timer+AT91_TC_SR, stat);

    // Start timer

    HAL_WRITE_UINT32(timer+AT91_TC_CCR, AT91_TC_CCR_TRIG | AT91_TC_CCR_CLKEN);

    // Wait for the compare

    do {

      HAL_READ_UINT32(timer+AT91_TC_SR, stat);

    } while ((stat & AT91_TC_SR_CPC) == 0);

}

#ifdef CYGFUN_HAL_ARM_AT91_PROFILE_TIMER

// Use TC1 for profiling

#define AT91_TC_PROFILE AT91_TC_TC1

#define HAL_INTERRUPT_PROFILE CYGNUM_HAL_INTERRUPT_TIMER1

// Profiling timer ISR

static cyg_uint32 profile_isr(CYG_ADDRWORD vector, CYG_ADDRWORD data, HAL_SavedRegisters *regs)

{

    cyg_uint32 status;

    HAL_READ_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_SR, status); // Clear interrupt

    HAL_INTERRUPT_ACKNOWLEDGE(HAL_INTERRUPT_PROFILE);

    __profile_hit(regs->pc);

    return CYG_ISR_HANDLED;

}

// Profiling timer setup

int hal_enable_profile_timer(int resolution)

{

    cyg_uint32 period;

    // Calculate how many timer ticks the requested resolution in

    // microseconds equates to. We do this calculation in 64 bit

    // arithmetic to avoid overflow.

    period = (cyg_uint32)((((cyg_uint64)resolution) *

        ((cyg_uint64)CYGNUM_HAL_ARM_AT91_CLOCK_SPEED))/32000000LL);

    CYG_ASSERT(period < 0x10000, "Invalid profile timer resolution"); // 16 bits only

    // Attach ISR

    HAL_INTERRUPT_ATTACH(HAL_INTERRUPT_PROFILE, &profile_isr, 0x1111, 0);

    HAL_INTERRUPT_UNMASK(HAL_INTERRUPT_PROFILE);

    // Disable counter

    HAL_WRITE_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_CCR, AT91_TC_CCR_CLKDIS);

    // Set registers

    HAL_WRITE_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_CMR, AT91_TC_CMR_CPCTRG | // Reset counter on CPC

                                                          AT91_TC_CMR_CLKS_MCK32); // Use MCLK/32

    HAL_WRITE_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_RC, period);

    // Start timer

    HAL_WRITE_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_CCR, AT91_TC_CCR_TRIG | AT91_TC_CCR_CLKEN);

    // Enable timer interrupt

    HAL_WRITE_UINT32(AT91_TC+AT91_TC_PROFILE+AT91_TC_IER, AT91_TC_IER_CPC);

    return resolution;

}

#endif // CYGFUN_HAL_ARM_AT91_PROFILE_TIMER

// timer_tc.c