mirror of https://gitee.com/openkylin/qemu.git
106 lines
3.0 KiB
C
106 lines
3.0 KiB
C
/*
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* ARM Versatile I2C controller
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*
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* Copyright (c) 2006-2007 CodeSourcery.
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* Copyright (c) 2012 Oskar Andero <oskar.andero@gmail.com>
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*
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* This file is derived from hw/realview.c by Paul Brook
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#include "sysbus.h"
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#include "bitbang_i2c.h"
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typedef struct {
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SysBusDevice busdev;
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MemoryRegion iomem;
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bitbang_i2c_interface *bitbang;
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int out;
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int in;
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} VersatileI2CState;
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static uint64_t versatile_i2c_read(void *opaque, target_phys_addr_t offset,
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unsigned size)
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{
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VersatileI2CState *s = (VersatileI2CState *)opaque;
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if (offset == 0) {
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return (s->out & 1) | (s->in << 1);
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} else {
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hw_error("%s: Bad offset 0x%x\n", __func__, (int)offset);
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return -1;
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}
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}
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static void versatile_i2c_write(void *opaque, target_phys_addr_t offset,
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uint64_t value, unsigned size)
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{
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VersatileI2CState *s = (VersatileI2CState *)opaque;
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switch (offset) {
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case 0:
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s->out |= value & 3;
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break;
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case 4:
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s->out &= ~value;
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break;
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default:
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hw_error("%s: Bad offset 0x%x\n", __func__, (int)offset);
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}
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bitbang_i2c_set(s->bitbang, BITBANG_I2C_SCL, (s->out & 1) != 0);
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s->in = bitbang_i2c_set(s->bitbang, BITBANG_I2C_SDA, (s->out & 2) != 0);
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}
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static const MemoryRegionOps versatile_i2c_ops = {
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.read = versatile_i2c_read,
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.write = versatile_i2c_write,
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.endianness = DEVICE_NATIVE_ENDIAN,
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};
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static int versatile_i2c_init(SysBusDevice *dev)
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{
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VersatileI2CState *s = FROM_SYSBUS(VersatileI2CState, dev);
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i2c_bus *bus;
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bus = i2c_init_bus(&dev->qdev, "i2c");
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s->bitbang = bitbang_i2c_init(bus);
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memory_region_init_io(&s->iomem, &versatile_i2c_ops, s,
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"versatile_i2c", 0x1000);
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sysbus_init_mmio(dev, &s->iomem);
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return 0;
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}
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static void versatile_i2c_class_init(ObjectClass *klass, void *data)
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{
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SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
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k->init = versatile_i2c_init;
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}
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static const TypeInfo versatile_i2c_info = {
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.name = "versatile_i2c",
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.parent = TYPE_SYS_BUS_DEVICE,
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.instance_size = sizeof(VersatileI2CState),
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.class_init = versatile_i2c_class_init,
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};
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static void versatile_i2c_register_types(void)
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{
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type_register_static(&versatile_i2c_info);
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}
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type_init(versatile_i2c_register_types)
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