binutils-gdb/sim/bfin/dv-bfin_twi.c

231 lines
6.2 KiB
C

/* Blackfin Two Wire Interface (TWI) 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 "devices.h"
#include "dv-bfin_twi.h"
/* XXX: This is merely a stub. */
struct bfin_twi
{
/* This top portion matches common dv_bfin struct. */
bu32 base;
struct hw *dma_master;
bool acked;
struct hw_event *handler;
char saved_byte;
int saved_count;
bu16 xmt_fifo, rcv_fifo;
/* Order after here is important -- matches hardware MMR layout. */
bu16 BFIN_MMR_16(clkdiv);
bu16 BFIN_MMR_16(control);
bu16 BFIN_MMR_16(slave_ctl);
bu16 BFIN_MMR_16(slave_stat);
bu16 BFIN_MMR_16(slave_addr);
bu16 BFIN_MMR_16(master_ctl);
bu16 BFIN_MMR_16(master_stat);
bu16 BFIN_MMR_16(master_addr);
bu16 BFIN_MMR_16(int_stat);
bu16 BFIN_MMR_16(int_mask);
bu16 BFIN_MMR_16(fifo_ctl);
bu16 BFIN_MMR_16(fifo_stat);
bu32 _pad0[20];
bu16 BFIN_MMR_16(xmt_data8);
bu16 BFIN_MMR_16(xmt_data16);
bu16 BFIN_MMR_16(rcv_data8);
bu16 BFIN_MMR_16(rcv_data16);
};
#define mmr_base() offsetof(struct bfin_twi, clkdiv)
#define mmr_offset(mmr) (offsetof(struct bfin_twi, mmr) - mmr_base())
#define mmr_idx(mmr) (mmr_offset (mmr) / 4)
static const char * const mmr_names[] =
{
"TWI_CLKDIV", "TWI_CONTROL", "TWI_SLAVE_CTL", "TWI_SLAVE_STAT",
"TWI_SLAVE_ADDR", "TWI_MASTER_CTL", "TWI_MASTER_STAT", "TWI_MASTER_ADDR",
"TWI_INT_STAT", "TWI_INT_MASK", "TWI_FIFO_CTL", "TWI_FIFO_STAT",
[mmr_idx (xmt_data8)] = "TWI_XMT_DATA8", "TWI_XMT_DATA16", "TWI_RCV_DATA8",
"TWI_RCV_DATA16",
};
#define mmr_name(off) (mmr_names[(off) / 4] ? : "<INV>")
static unsigned
bfin_twi_io_write_buffer (struct hw *me, const void *source, int space,
address_word addr, unsigned nr_bytes)
{
struct bfin_twi *twi = hw_data (me);
bu32 mmr_off;
bu32 value;
bu16 *valuep;
value = dv_load_2 (source);
mmr_off = addr - twi->base;
valuep = (void *)((unsigned long)twi + mmr_base() + mmr_off);
HW_TRACE_WRITE ();
dv_bfin_mmr_require_16 (me, addr, nr_bytes, true);
switch (mmr_off)
{
case mmr_offset(clkdiv):
case mmr_offset(control):
case mmr_offset(slave_ctl):
case mmr_offset(slave_addr):
case mmr_offset(master_ctl):
case mmr_offset(master_addr):
case mmr_offset(int_mask):
case mmr_offset(fifo_ctl):
*valuep = value;
break;
case mmr_offset(int_stat):
dv_w1c_2 (valuep, value, -1);
break;
case mmr_offset(master_stat):
dv_w1c_2 (valuep, value, BUFWRERR | BUFRDERR | DNAK | ANAK | LOSTARB);
break;
case mmr_offset(slave_stat):
case mmr_offset(fifo_stat):
case mmr_offset(rcv_data8):
case mmr_offset(rcv_data16):
/* These are all RO. XXX: Does these throw error ? */
break;
case mmr_offset(xmt_data8):
value &= 0xff;
case mmr_offset(xmt_data16):
twi->xmt_fifo = value;
break;
default:
dv_bfin_mmr_invalid (me, addr, nr_bytes, true);
break;
}
return nr_bytes;
}
static unsigned
bfin_twi_io_read_buffer (struct hw *me, void *dest, int space,
address_word addr, unsigned nr_bytes)
{
struct bfin_twi *twi = hw_data (me);
bu32 mmr_off;
bu16 *valuep;
mmr_off = addr - twi->base;
valuep = (void *)((unsigned long)twi + mmr_base() + mmr_off);
HW_TRACE_READ ();
dv_bfin_mmr_require_16 (me, addr, nr_bytes, false);
switch (mmr_off)
{
case mmr_offset(clkdiv):
case mmr_offset(control):
case mmr_offset(slave_ctl):
case mmr_offset(slave_stat):
case mmr_offset(slave_addr):
case mmr_offset(master_ctl):
case mmr_offset(master_stat):
case mmr_offset(master_addr):
case mmr_offset(int_stat):
case mmr_offset(int_mask):
case mmr_offset(fifo_ctl):
case mmr_offset(fifo_stat):
dv_store_2 (dest, *valuep);
break;
case mmr_offset(rcv_data8):
case mmr_offset(rcv_data16):
dv_store_2 (dest, twi->rcv_fifo);
break;
case mmr_offset(xmt_data8):
case mmr_offset(xmt_data16):
/* These always read as 0. */
dv_store_2 (dest, 0);
break;
default:
dv_bfin_mmr_invalid (me, addr, nr_bytes, false);
break;
}
return nr_bytes;
}
static const struct hw_port_descriptor bfin_twi_ports[] =
{
{ "stat", 0, 0, output_port, },
{ NULL, 0, 0, 0, },
};
static void
attach_bfin_twi_regs (struct hw *me, struct bfin_twi *twi)
{
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_TWI_SIZE)
hw_abort (me, "\"reg\" size must be %#x", BFIN_MMR_TWI_SIZE);
hw_attach_address (hw_parent (me),
0, attach_space, attach_address, attach_size, me);
twi->base = attach_address;
}
static void
bfin_twi_finish (struct hw *me)
{
struct bfin_twi *twi;
twi = HW_ZALLOC (me, struct bfin_twi);
set_hw_data (me, twi);
set_hw_io_read_buffer (me, bfin_twi_io_read_buffer);
set_hw_io_write_buffer (me, bfin_twi_io_write_buffer);
set_hw_ports (me, bfin_twi_ports);
attach_bfin_twi_regs (me, twi);
}
const struct hw_descriptor dv_bfin_twi_descriptor[] =
{
{"bfin_twi", bfin_twi_finish,},
{NULL, NULL},
};