old-cross-binutils/sim/bfin/dv-bfin_rtc.c
Mike Frysinger 466b619e95 sim: bfin: push down mmr address/size checks
The bfin port is using the WITH_DEVICES framework for two reasons:
- get access to the cpu making the request (if available)
- check the alignment & size for core & system MMRs

We addressed the first part with commit dea10706e9,
and we handle the second part with this commit.  Arguably this is more
correct too because trying to do bad reads/writes directly (when devices
support is disabled) often results in bad memory accesses.

As part of this clean up, we also adjust all of the existing logic that
would reject invalid accesses: the code was relying on the checks never
returning, but that's not the case when things like gdb (via the user's
commands) are making the requests.  Thus we'd still end up with bad mem
accesses, or sometimes gdb being hung due to while(1) loops.

Now we can connect (most of) these models into any address and have them
work correctly.
2015-12-26 19:09:43 -05:00

205 lines
5.1 KiB
C

/* Blackfin Real Time Clock (RTC) model.
Copyright (C) 2010-2015 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/>. */
#include "config.h"
#include <time.h>
#include "sim-main.h"
#include "dv-sockser.h"
#include "devices.h"
#include "dv-bfin_rtc.h"
/* XXX: This read-only stub setup is based on host system clock. */
struct bfin_rtc
{
bu32 base;
bu32 stat_shadow;
/* Order after here is important -- matches hardware MMR layout. */
bu32 stat;
bu16 BFIN_MMR_16(ictl);
bu16 BFIN_MMR_16(istat);
bu16 BFIN_MMR_16(swcnt);
bu32 alarm;
bu16 BFIN_MMR_16(pren);
};
#define mmr_base() offsetof(struct bfin_rtc, stat)
#define mmr_offset(mmr) (offsetof(struct bfin_rtc, mmr) - mmr_base())
static const char * const mmr_names[] =
{
"RTC_STAT", "RTC_ICTL", "RTC_ISTAT", "RTC_SWCNT", "RTC_ALARM", "RTC_PREN",
};
#define mmr_name(off) mmr_names[(off) / 4]
static unsigned
bfin_rtc_io_write_buffer (struct hw *me, const void *source,
int space, address_word addr, unsigned nr_bytes)
{
struct bfin_rtc *rtc = hw_data (me);
bu32 mmr_off;
bu32 value;
bu16 *value16p;
bu32 *value32p;
void *valuep;
/* Invalid access mode is higher priority than missing register. */
if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, true))
return 0;
if (nr_bytes == 4)
value = dv_load_4 (source);
else
value = dv_load_2 (source);
mmr_off = addr - rtc->base;
valuep = (void *)((unsigned long)rtc + mmr_base() + mmr_off);
value16p = valuep;
value32p = valuep;
HW_TRACE_WRITE ();
/* XXX: These probably need more work. */
switch (mmr_off)
{
case mmr_offset(stat):
/* XXX: Ignore these since we are wired to host. */
break;
case mmr_offset(istat):
dv_w1c_2 (value16p, value, ~(1 << 14));
break;
case mmr_offset(alarm):
break;
case mmr_offset(ictl):
/* XXX: This should schedule an event handler. */
case mmr_offset(swcnt):
case mmr_offset(pren):
break;
}
return nr_bytes;
}
static unsigned
bfin_rtc_io_read_buffer (struct hw *me, void *dest,
int space, address_word addr, unsigned nr_bytes)
{
struct bfin_rtc *rtc = hw_data (me);
bu32 mmr_off;
bu16 *value16p;
bu32 *value32p;
void *valuep;
/* Invalid access mode is higher priority than missing register. */
if (!dv_bfin_mmr_require_16_32 (me, addr, nr_bytes, false))
return 0;
mmr_off = addr - rtc->base;
valuep = (void *)((unsigned long)rtc + mmr_base() + mmr_off);
value16p = valuep;
value32p = valuep;
HW_TRACE_READ ();
switch (mmr_off)
{
case mmr_offset(stat):
{
time_t t = time (NULL);
struct tm *tm = localtime (&t);
bu32 value =
(((tm->tm_year - 70) * 365 + tm->tm_yday) << 17) |
(tm->tm_hour << 12) |
(tm->tm_min << 6) |
(tm->tm_sec << 0);
dv_store_4 (dest, value);
break;
}
case mmr_offset(alarm):
dv_store_4 (dest, *value32p);
break;
case mmr_offset(istat):
case mmr_offset(ictl):
case mmr_offset(swcnt):
case mmr_offset(pren):
dv_store_2 (dest, *value16p);
break;
}
return nr_bytes;
}
static const struct hw_port_descriptor bfin_rtc_ports[] =
{
{ "rtc", 0, 0, output_port, },
{ NULL, 0, 0, 0, },
};
static void
attach_bfin_rtc_regs (struct hw *me, struct bfin_rtc *rtc)
{
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_MMR_RTC_SIZE)
hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_RTC_SIZE);
hw_attach_address (hw_parent (me),
0, attach_space, attach_address, attach_size, me);
rtc->base = attach_address;
}
static void
bfin_rtc_finish (struct hw *me)
{
struct bfin_rtc *rtc;
rtc = HW_ZALLOC (me, struct bfin_rtc);
set_hw_data (me, rtc);
set_hw_io_read_buffer (me, bfin_rtc_io_read_buffer);
set_hw_io_write_buffer (me, bfin_rtc_io_write_buffer);
set_hw_ports (me, bfin_rtc_ports);
attach_bfin_rtc_regs (me, rtc);
/* Initialize the RTC. */
}
const struct hw_descriptor dv_bfin_rtc_descriptor[] =
{
{"bfin_rtc", bfin_rtc_finish,},
{NULL, NULL},
};