diff options
Diffstat (limited to 'sim/bfin/dv-bfin_wdog.c')
| -rw-r--r-- | sim/bfin/dv-bfin_wdog.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/sim/bfin/dv-bfin_wdog.c b/sim/bfin/dv-bfin_wdog.c new file mode 100644 index 0000000..4aada47 --- /dev/null +++ b/sim/bfin/dv-bfin_wdog.c @@ -0,0 +1,206 @@ +/* Blackfin Watchdog (WDOG) model. + + Copyright (C) 2010-2011 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 "sim-main.h" +#include "dv-sockser.h" +#include "devices.h" +#include "dv-bfin_wdog.h" + +/* XXX: Should we bother emulating the TX/RX FIFOs ? */ + +struct bfin_wdog +{ + bu32 base; + + /* Order after here is important -- matches hardware MMR layout. */ + bu16 BFIN_MMR_16(ctl); + bu32 cnt, stat; +}; +#define mmr_base() offsetof(struct bfin_wdog, ctl) +#define mmr_offset(mmr) (offsetof(struct bfin_wdog, mmr) - mmr_base()) + +static const char * const mmr_names[] = { + "WDOG_CTL", "WDOG_CNT", "WDOG_STAT", +}; +#define mmr_name(off) mmr_names[(off) / 4] + +static bool +bfin_wdog_enabled (struct bfin_wdog *wdog) +{ + return ((wdog->ctl & WDEN) != WDDIS); +} + +static unsigned +bfin_wdog_io_write_buffer (struct hw *me, const void *source, + int space, address_word addr, unsigned nr_bytes) +{ + struct bfin_wdog *wdog = hw_data (me); + bu32 mmr_off; + bu32 value; + bu16 *value16p; + bu32 *value32p; + void *valuep; + + if (nr_bytes == 4) + value = dv_load_4 (source); + else + value = dv_load_2 (source); + + mmr_off = addr - wdog->base; + valuep = (void *)((unsigned long)wdog + mmr_base() + mmr_off); + value16p = valuep; + value32p = valuep; + + HW_TRACE_WRITE (); + + switch (mmr_off) + { + case mmr_offset(ctl): + dv_w1c_2_partial (value16p, value, WDRO); + /* XXX: Should enable an event here to handle timeouts. */ + break; + + case mmr_offset(cnt): + /* Writes are discarded when enabeld. */ + if (!bfin_wdog_enabled (wdog)) + { + *value32p = value; + /* Writes to CNT preloads the STAT. */ + wdog->stat = wdog->cnt; + } + break; + + case mmr_offset(stat): + /* When enabled, writes to STAT reload the counter. */ + if (bfin_wdog_enabled (wdog)) + wdog->stat = wdog->cnt; + /* XXX: When disabled, are writes just ignored ? */ + break; + } + + return nr_bytes; +} + +static unsigned +bfin_wdog_io_read_buffer (struct hw *me, void *dest, + int space, address_word addr, unsigned nr_bytes) +{ + struct bfin_wdog *wdog = hw_data (me); + bu32 mmr_off; + bu16 *value16p; + bu32 *value32p; + void *valuep; + + mmr_off = addr - wdog->base; + valuep = (void *)((unsigned long)wdog + mmr_base() + mmr_off); + value16p = valuep; + value32p = valuep; + + HW_TRACE_READ (); + + switch (mmr_off) + { + case mmr_offset(ctl): + dv_bfin_mmr_require_16 (me, addr, nr_bytes, false); + dv_store_2 (dest, *value16p); + break; + + case mmr_offset(cnt): + case mmr_offset(stat): + dv_store_4 (dest, *value32p); + break; + } + + return nr_bytes; +} + +static const struct hw_port_descriptor bfin_wdog_ports[] = { + { "reset", WDEV_RESET, 0, output_port, }, + { "nmi", WDEV_NMI, 0, output_port, }, + { "gpi", WDEV_GPI, 0, output_port, }, + { NULL, 0, 0, 0, }, +}; + +static void +bfin_wdog_port_event (struct hw *me, int my_port, struct hw *source, + int source_port, int level) +{ + struct bfin_wdog *wdog = hw_data (me); + bu16 wdev; + + wdog->ctl |= WDRO; + wdev = (wdog->ctl & WDEV); + if (wdev != WDEV_NONE) + hw_port_event (me, wdev, 1); +} + +static void +attach_bfin_wdog_regs (struct hw *me, struct bfin_wdog *wdog) +{ + 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, ®)) + hw_abort (me, "\"reg\" property must contain three addr/size entries"); + + hw_unit_address_to_attach_address (hw_parent (me), + ®.address, + &attach_space, &attach_address, me); + hw_unit_size_to_attach_size (hw_parent (me), ®.size, &attach_size, me); + + if (attach_size != BFIN_MMR_WDOG_SIZE) + hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_WDOG_SIZE); + + hw_attach_address (hw_parent (me), + 0, attach_space, attach_address, attach_size, me); + + wdog->base = attach_address; +} + +static void +bfin_wdog_finish (struct hw *me) +{ + struct bfin_wdog *wdog; + + wdog = HW_ZALLOC (me, struct bfin_wdog); + + set_hw_data (me, wdog); + set_hw_io_read_buffer (me, bfin_wdog_io_read_buffer); + set_hw_io_write_buffer (me, bfin_wdog_io_write_buffer); + set_hw_ports (me, bfin_wdog_ports); + set_hw_port_event (me, bfin_wdog_port_event); + + attach_bfin_wdog_regs (me, wdog); + + /* Initialize the Watchdog. */ + wdog->ctl = WDDIS; +} + +const struct hw_descriptor dv_bfin_wdog_descriptor[] = { + {"bfin_wdog", bfin_wdog_finish,}, + {NULL, NULL}, +}; |