genode/base-hw/src/core/timer/exynos_mct.h

146 lines
2.8 KiB
C++

/*
* \brief Timer for core
* \author Martin stein
* \date 2013-01-10
*/
/*
* Copyright (C) 2013 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _TIMER__EXYNOS_MCT_H_
#define _TIMER__EXYNOS_MCT_H_
/* Genode includes */
#include <util/mmio.h>
namespace Exynos_mct
{
using namespace Genode;
/**
* Timer for core
*/
class Timer : public Mmio
{
enum {
PRESCALER = 1,
DIV_MUX = 0,
};
/**
* MCT configuration
*/
struct Mct_cfg : Register<0x0, 32>
{
struct Prescaler : Bitfield<0, 8> { };
struct Div_mux : Bitfield<8, 3> { };
};
/**
* Local timer 0 free running counter buffer
*/
struct L0_frcntb : Register<0x310, 32> { };
/**
* Local timer 0 configuration
*/
struct L0_tcon : Register<0x320, 32>
{
struct Frc_start : Bitfield<3, 1> { };
};
/**
* Local timer 0 expired status
*/
struct L0_int_cstat : Register<0x330, 32, true>
{
struct Frcnt : Bitfield<1, 1> { };
};
/**
* Local timer 0 interrupt enable
*/
struct L0_int_enb : Register<0x334, 32>
{
struct Frceie : Bitfield<1, 1> { };
};
/**
* Local timer 0 write status
*/
struct L0_wstat : Register<0x340, 32, true>
{
struct Frcntb : Bitfield<2, 1> { };
struct Tcon : Bitfield<3, 1> { };
};
/**
* Write to reg that replies via ack bit and clear ack bit
*/
template <typename DEST, typename ACK>
void _acked_write(typename DEST::Register_base::access_t const v)
{
typedef typename DEST::Register_base Dest;
typedef typename ACK::Bitfield_base Ack;
write<Dest>(v);
while (!read<Ack>());
write<Ack>(1);
}
float const _tics_per_ms;
/**
* Start and stop counting
*/
void _run(bool const run)
{
_acked_write<L0_tcon, L0_wstat::Tcon>
(L0_tcon::Frc_start::bits(run));
}
public:
/**
* Constructor
*/
Timer(addr_t const base, unsigned const clk)
: Mmio(base), _tics_per_ms((float)clk / (PRESCALER + 1) / (1 << DIV_MUX) / 1000)
{
Mct_cfg::access_t mct_cfg = 0;
Mct_cfg::Prescaler::set(mct_cfg, PRESCALER);
Mct_cfg::Div_mux::set(mct_cfg, DIV_MUX);
write<Mct_cfg>(mct_cfg);
write<L0_int_enb>(L0_int_enb::Frceie::bits(1));
}
/**
* Start one-shot run with an IRQ delay of 'tics'
*/
inline void start_one_shot(unsigned const tics)
{
_run(0);
_acked_write<L0_frcntb, L0_wstat::Frcntb>(tics);
_run(1);
}
/**
* Translate 'ms' milliseconds to a native timer value
*/
unsigned ms_to_tics(unsigned const ms)
{
return ms * _tics_per_ms;
}
/**
* Clear interrupt output line
*/
void clear_interrupt() { write<L0_int_cstat::Frcnt>(1); }
};
}
#endif /* _TIMER__EXYNOS_MCT_H_ */