Projet_SETI_RISC-V/riscv-gnu-toolchain/binutils/sim/bfin/dv-bfin_ctimer.c
2023-03-06 14:48:14 +01:00

279 lines
7 KiB
C

/* Blackfin Core Timer model.
Copyright (C) 2010-2022 Free Software Foundation, Inc.
Contributed by Analog Devices, Inc.
This file is part of simulators.
This program 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 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT 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 this program. If not, see <http://www.gnu.org/licenses/>. */
/* This must come before any other includes. */
#include "defs.h"
#include "sim-main.h"
#include "devices.h"
#include "dv-bfin_cec.h"
#include "dv-bfin_ctimer.h"
struct bfin_ctimer
{
bu32 base;
struct hw_event *handler;
int64_t timeout;
/* Order after here is important -- matches hardware MMR layout. */
bu32 tcntl, tperiod, tscale, tcount;
};
#define mmr_base() offsetof(struct bfin_ctimer, tcntl)
#define mmr_offset(mmr) (offsetof(struct bfin_ctimer, mmr) - mmr_base())
static const char * const mmr_names[] =
{
"TCNTL", "TPERIOD", "TSCALE", "TCOUNT",
};
#define mmr_name(off) mmr_names[(off) / 4]
static bool
bfin_ctimer_enabled (struct bfin_ctimer *ctimer)
{
return (ctimer->tcntl & TMPWR) && (ctimer->tcntl & TMREN);
}
static bu32
bfin_ctimer_scale (struct bfin_ctimer *ctimer)
{
/* Only low 8 bits are actually checked. */
return (ctimer->tscale & 0xff) + 1;
}
static void
bfin_ctimer_schedule (struct hw *me, struct bfin_ctimer *ctimer);
static void
bfin_ctimer_expire (struct hw *me, void *data)
{
struct bfin_ctimer *ctimer = data;
ctimer->tcntl |= TINT;
if (ctimer->tcntl & TAUTORLD)
{
ctimer->tcount = ctimer->tperiod;
bfin_ctimer_schedule (me, ctimer);
}
else
{
ctimer->tcount = 0;
ctimer->handler = NULL;
}
hw_port_event (me, IVG_IVTMR, 1);
}
static void
bfin_ctimer_update_count (struct hw *me, struct bfin_ctimer *ctimer)
{
bu32 scale, ticks;
int64_t timeout;
/* If the timer was enabled w/out autoreload and has expired, then
there's nothing to calculate here. */
if (ctimer->handler == NULL)
return;
scale = bfin_ctimer_scale (ctimer);
timeout = hw_event_remain_time (me, ctimer->handler);
ticks = ctimer->timeout - timeout;
ctimer->tcount -= (scale * ticks);
ctimer->timeout = timeout;
}
static void
bfin_ctimer_deschedule (struct hw *me, struct bfin_ctimer *ctimer)
{
if (ctimer->handler)
{
hw_event_queue_deschedule (me, ctimer->handler);
ctimer->handler = NULL;
}
}
static void
bfin_ctimer_schedule (struct hw *me, struct bfin_ctimer *ctimer)
{
bu32 scale = bfin_ctimer_scale (ctimer);
ctimer->timeout = (ctimer->tcount / scale) + !!(ctimer->tcount % scale);
ctimer->handler = hw_event_queue_schedule (me, ctimer->timeout,
bfin_ctimer_expire,
ctimer);
}
static unsigned
bfin_ctimer_io_write_buffer (struct hw *me, const void *source,
int space, address_word addr, unsigned nr_bytes)
{
struct bfin_ctimer *ctimer = hw_data (me);
bool curr_enabled;
bu32 mmr_off;
bu32 value;
bu32 *valuep;
/* Invalid access mode is higher priority than missing register. */
if (!dv_bfin_mmr_require_32 (me, addr, nr_bytes, true))
return 0;
value = dv_load_4 (source);
mmr_off = addr - ctimer->base;
valuep = (void *)((uintptr_t)ctimer + mmr_base() + mmr_off);
HW_TRACE_WRITE ();
curr_enabled = bfin_ctimer_enabled (ctimer);
switch (mmr_off)
{
case mmr_offset(tcntl):
/* HRM describes TINT as sticky, but it isn't W1C. */
*valuep = value;
if (bfin_ctimer_enabled (ctimer) == curr_enabled)
{
/* Do nothing. */
}
else if (curr_enabled)
{
bfin_ctimer_update_count (me, ctimer);
bfin_ctimer_deschedule (me, ctimer);
}
else
bfin_ctimer_schedule (me, ctimer);
break;
case mmr_offset(tcount):
/* HRM says writes are discarded when enabled. */
/* XXX: But hardware seems to be writeable all the time ? */
/* if (!curr_enabled) */
*valuep = value;
break;
case mmr_offset(tperiod):
/* HRM says writes are discarded when enabled. */
/* XXX: But hardware seems to be writeable all the time ? */
/* if (!curr_enabled) */
{
/* Writes are mirrored into TCOUNT. */
ctimer->tcount = value;
*valuep = value;
}
break;
case mmr_offset(tscale):
if (curr_enabled)
{
bfin_ctimer_update_count (me, ctimer);
bfin_ctimer_deschedule (me, ctimer);
}
*valuep = value;
if (curr_enabled)
bfin_ctimer_schedule (me, ctimer);
break;
}
return nr_bytes;
}
static unsigned
bfin_ctimer_io_read_buffer (struct hw *me, void *dest,
int space, address_word addr, unsigned nr_bytes)
{
struct bfin_ctimer *ctimer = hw_data (me);
bu32 mmr_off;
bu32 *valuep;
/* Invalid access mode is higher priority than missing register. */
if (!dv_bfin_mmr_require_32 (me, addr, nr_bytes, false))
return 0;
mmr_off = addr - ctimer->base;
valuep = (void *)((uintptr_t)ctimer + mmr_base() + mmr_off);
HW_TRACE_READ ();
switch (mmr_off)
{
case mmr_offset(tcount):
/* Since we're optimizing events here, we need to calculate
the new tcount value. */
if (bfin_ctimer_enabled (ctimer))
bfin_ctimer_update_count (me, ctimer);
break;
}
dv_store_4 (dest, *valuep);
return nr_bytes;
}
static const struct hw_port_descriptor bfin_ctimer_ports[] =
{
{ "ivtmr", IVG_IVTMR, 0, output_port, },
{ NULL, 0, 0, 0, },
};
static void
attach_bfin_ctimer_regs (struct hw *me, struct bfin_ctimer *ctimer)
{
address_word attach_address;
int attach_space;
unsigned attach_size;
reg_property_spec reg;
if (hw_find_property (me, "reg") == NULL)
hw_abort (me, "Missing \"reg\" property");
if (!hw_find_reg_array_property (me, "reg", 0, &reg))
hw_abort (me, "\"reg\" property must contain three addr/size entries");
hw_unit_address_to_attach_address (hw_parent (me),
&reg.address,
&attach_space, &attach_address, me);
hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
if (attach_size != BFIN_COREMMR_CTIMER_SIZE)
hw_abort (me, "\"reg\" size must be %#x", BFIN_COREMMR_CTIMER_SIZE);
hw_attach_address (hw_parent (me),
0, attach_space, attach_address, attach_size, me);
ctimer->base = attach_address;
}
static void
bfin_ctimer_finish (struct hw *me)
{
struct bfin_ctimer *ctimer;
ctimer = HW_ZALLOC (me, struct bfin_ctimer);
set_hw_data (me, ctimer);
set_hw_io_read_buffer (me, bfin_ctimer_io_read_buffer);
set_hw_io_write_buffer (me, bfin_ctimer_io_write_buffer);
set_hw_ports (me, bfin_ctimer_ports);
attach_bfin_ctimer_regs (me, ctimer);
/* Initialize the Core Timer. */
}
const struct hw_descriptor dv_bfin_ctimer_descriptor[] =
{
{"bfin_ctimer", bfin_ctimer_finish,},
{NULL, NULL},
};