NetBSD/sys/arch/dreamcast/dev/g2/g2bus_bus_mem.c

246 lines
6.1 KiB
C

/* $NetBSD: g2bus_bus_mem.c,v 1.5 2002/03/03 14:31:29 uch Exp $ */
/*-
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Bus space implementation for the SEGA G2 bus.
*
* NOTE: We only implement a small subset of what the bus_space(9)
* API specifies. Right now, the GAPS PCI bridge is only used for
* the Dreamcast Broadband Adatper, so we only provide what the
* pci(4) and rtk(4) drivers need.
*/
#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <machine/cpu.h>
#include <machine/bus.h>
#include <dreamcast/dev/g2/g2busvar.h>
int g2bus_bus_mem_map(void *, bus_addr_t, bus_size_t, int,
bus_space_handle_t *);
void g2bus_bus_mem_unmap(void *, bus_space_handle_t, bus_size_t);
u_int8_t g2bus_bus_mem_read_1(void *, bus_space_handle_t, bus_size_t);
u_int16_t g2bus_bus_mem_read_2(void *, bus_space_handle_t, bus_size_t);
u_int32_t g2bus_bus_mem_read_4(void *, bus_space_handle_t, bus_size_t);
void g2bus_bus_mem_write_1(void *, bus_space_handle_t, bus_size_t,
u_int8_t);
void g2bus_bus_mem_write_2(void *, bus_space_handle_t, bus_size_t,
u_int16_t);
void g2bus_bus_mem_write_4(void *, bus_space_handle_t, bus_size_t,
u_int32_t);
void g2bus_bus_mem_read_region_1(void *, bus_space_handle_t, bus_size_t,
u_int8_t *, bus_size_t);
void g2bus_bus_mem_write_region_1(void *, bus_space_handle_t, bus_size_t,
const u_int8_t *, bus_size_t);
void
g2bus_bus_mem_init(struct g2bus_softc *sc)
{
bus_space_tag_t t = &sc->sc_memt;
memset(t, 0, sizeof(*t));
t->dbs_map = g2bus_bus_mem_map;
t->dbs_unmap = g2bus_bus_mem_unmap;
t->dbs_r_1 = g2bus_bus_mem_read_1;
t->dbs_r_2 = g2bus_bus_mem_read_2;
t->dbs_r_4 = g2bus_bus_mem_read_4;
t->dbs_w_1 = g2bus_bus_mem_write_1;
t->dbs_w_2 = g2bus_bus_mem_write_2;
t->dbs_w_4 = g2bus_bus_mem_write_4;
t->dbs_rr_1 = g2bus_bus_mem_read_region_1;
t->dbs_wr_1 = g2bus_bus_mem_write_region_1;
}
int
g2bus_bus_mem_map(void *v, bus_addr_t addr, bus_size_t size, int flags,
bus_space_handle_t *shp)
{
KASSERT((addr & SH3_PHYS_MASK) == addr);
*shp = SH3_PHYS_TO_P2SEG(addr);
return (0);
}
void
g2bus_bus_mem_unmap(void *v, bus_space_handle_t sh, bus_size_t size)
{
KASSERT(sh >= SH3_P2SEG_BASE && sh <= SH3_P2SEG_END);
/* Nothing to do. */
}
/*
* G2 bus cycles must not be interrupted by IRQs or G2 DMA.
* The following paired macros will take the necessary precautions.
*/
#define G2_LOCK \
do { \
_cpu_exception_suspend(); \
/* suspend any G2 DMA here... */ \
while((*(volatile unsigned int *)0xa05f688c) & 32); \
} while(/*CONSTCOND*/0)
#define G2_UNLOCK \
do { \
/* resume any G2 DMA here... */ \
_cpu_exception_resume(0); \
} while(/*CONSTCOND*/0)
u_int8_t
g2bus_bus_mem_read_1(void *v, bus_space_handle_t sh, bus_size_t off)
{
u_int8_t rv;
G2_LOCK;
rv = *(__volatile u_int8_t *)(sh + off);
G2_UNLOCK;
return (rv);
}
u_int16_t
g2bus_bus_mem_read_2(void *v, bus_space_handle_t sh, bus_size_t off)
{
u_int16_t rv;
G2_LOCK;
rv = *(__volatile u_int16_t *)(sh + off);
G2_UNLOCK;
return (rv);
}
u_int32_t
g2bus_bus_mem_read_4(void *v, bus_space_handle_t sh, bus_size_t off)
{
u_int32_t rv;
G2_LOCK;
rv = *(__volatile u_int32_t *)(sh + off);
G2_UNLOCK;
return (rv);
}
void
g2bus_bus_mem_write_1(void *v, bus_space_handle_t sh, bus_size_t off,
u_int8_t val)
{
G2_LOCK;
*(__volatile u_int8_t *)(sh + off) = val;
G2_UNLOCK;
}
void
g2bus_bus_mem_write_2(void *v, bus_space_handle_t sh, bus_size_t off,
u_int16_t val)
{
G2_LOCK;
*(__volatile u_int16_t *)(sh + off) = val;
G2_UNLOCK;
}
void
g2bus_bus_mem_write_4(void *v, bus_space_handle_t sh, bus_size_t off,
u_int32_t val)
{
G2_LOCK;
*(__volatile u_int32_t *)(sh + off) = val;
G2_UNLOCK;
}
void
g2bus_bus_mem_read_region_1(void *v, bus_space_handle_t sh, bus_size_t off,
u_int8_t *addr, bus_size_t len)
{
__volatile const u_int8_t *baddr = (u_int8_t *)(sh + off);
G2_LOCK;
while (len--)
*addr++ = *baddr++;
G2_UNLOCK;
}
void
g2bus_bus_mem_write_region_1(void *v, bus_space_handle_t sh, bus_size_t off,
const u_int8_t *addr, bus_size_t len)
{
__volatile u_int8_t *baddr = (u_int8_t *)(sh + off);
G2_LOCK;
while (len--)
*baddr++ = *addr++;
G2_UNLOCK;
}