--- /dev/null
+/*
+ * Exynos4210 I2C Bus Serial Interface Emulation
+ *
+ * Copyright (C) 2012 Samsung Electronics Co Ltd.
+ * Maksim Kozlov, <m.kozlov@samsung.com>
+ * Igor Mitsyanko, <i.mitsyanko@samsung.com>
+ *
+ * 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 2 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 "qemu/timer.h"
+#include "hw/sysbus.h"
+#include "hw/i2c/i2c.h"
+
+#ifndef EXYNOS4_I2C_DEBUG
+#define EXYNOS4_I2C_DEBUG 0
+#endif
+
+#define TYPE_EXYNOS4_I2C "exynos4210.i2c"
+#define EXYNOS4_I2C(obj) \
+ OBJECT_CHECK(Exynos4210I2CState, (obj), TYPE_EXYNOS4_I2C)
+
+/* Exynos4210 I2C memory map */
+#define EXYNOS4_I2C_MEM_SIZE 0x14
+#define I2CCON_ADDR 0x00 /* control register */
+#define I2CSTAT_ADDR 0x04 /* control/status register */
+#define I2CADD_ADDR 0x08 /* address register */
+#define I2CDS_ADDR 0x0c /* data shift register */
+#define I2CLC_ADDR 0x10 /* line control register */
+
+#define I2CCON_ACK_GEN (1 << 7)
+#define I2CCON_INTRS_EN (1 << 5)
+#define I2CCON_INT_PEND (1 << 4)
+
+#define EXYNOS4_I2C_MODE(reg) (((reg) >> 6) & 3)
+#define I2C_IN_MASTER_MODE(reg) (((reg) >> 6) & 2)
+#define I2CMODE_MASTER_Rx 0x2
+#define I2CMODE_MASTER_Tx 0x3
+#define I2CSTAT_LAST_BIT (1 << 0)
+#define I2CSTAT_OUTPUT_EN (1 << 4)
+#define I2CSTAT_START_BUSY (1 << 5)
+
+
+#if EXYNOS4_I2C_DEBUG
+#define DPRINT(fmt, args...) \
+ do { fprintf(stderr, "QEMU I2C: "fmt, ## args); } while (0)
+
+static const char *exynos4_i2c_get_regname(unsigned offset)
+{
+ switch (offset) {
+ case I2CCON_ADDR:
+ return "I2CCON";
+ case I2CSTAT_ADDR:
+ return "I2CSTAT";
+ case I2CADD_ADDR:
+ return "I2CADD";
+ case I2CDS_ADDR:
+ return "I2CDS";
+ case I2CLC_ADDR:
+ return "I2CLC";
+ default:
+ return "[?]";
+ }
+}
+
+#else
+#define DPRINT(fmt, args...) do { } while (0)
+#endif
+
+typedef struct Exynos4210I2CState {
+ SysBusDevice parent_obj;
+
+ MemoryRegion iomem;
+ I2CBus *bus;
+ qemu_irq irq;
+
+ uint8_t i2ccon;
+ uint8_t i2cstat;
+ uint8_t i2cadd;
+ uint8_t i2cds;
+ uint8_t i2clc;
+ bool scl_free;
+} Exynos4210I2CState;
+
+static inline void exynos4210_i2c_raise_interrupt(Exynos4210I2CState *s)
+{
+ if (s->i2ccon & I2CCON_INTRS_EN) {
+ s->i2ccon |= I2CCON_INT_PEND;
+ qemu_irq_raise(s->irq);
+ }
+}
+
+static void exynos4210_i2c_data_receive(void *opaque)
+{
+ Exynos4210I2CState *s = (Exynos4210I2CState *)opaque;
+ int ret;
+
+ s->i2cstat &= ~I2CSTAT_LAST_BIT;
+ s->scl_free = false;
+ ret = i2c_recv(s->bus);
+ if (ret < 0 && (s->i2ccon & I2CCON_ACK_GEN)) {
+ s->i2cstat |= I2CSTAT_LAST_BIT; /* Data is not acknowledged */
+ } else {
+ s->i2cds = ret;
+ }
+ exynos4210_i2c_raise_interrupt(s);
+}
+
+static void exynos4210_i2c_data_send(void *opaque)
+{
+ Exynos4210I2CState *s = (Exynos4210I2CState *)opaque;
+
+ s->i2cstat &= ~I2CSTAT_LAST_BIT;
+ s->scl_free = false;
+ if (i2c_send(s->bus, s->i2cds) < 0 && (s->i2ccon & I2CCON_ACK_GEN)) {
+ s->i2cstat |= I2CSTAT_LAST_BIT;
+ }
+ exynos4210_i2c_raise_interrupt(s);
+}
+
+static uint64_t exynos4210_i2c_read(void *opaque, hwaddr offset,
+ unsigned size)
+{
+ Exynos4210I2CState *s = (Exynos4210I2CState *)opaque;
+ uint8_t value;
+
+ switch (offset) {
+ case I2CCON_ADDR:
+ value = s->i2ccon;
+ break;
+ case I2CSTAT_ADDR:
+ value = s->i2cstat;
+ break;
+ case I2CADD_ADDR:
+ value = s->i2cadd;
+ break;
+ case I2CDS_ADDR:
+ value = s->i2cds;
+ s->scl_free = true;
+ if (EXYNOS4_I2C_MODE(s->i2cstat) == I2CMODE_MASTER_Rx &&
+ (s->i2cstat & I2CSTAT_START_BUSY) &&
+ !(s->i2ccon & I2CCON_INT_PEND)) {
+ exynos4210_i2c_data_receive(s);
+ }
+ break;
+ case I2CLC_ADDR:
+ value = s->i2clc;
+ break;
+ default:
+ value = 0;
+ DPRINT("ERROR: Bad read offset 0x%x\n", (unsigned int)offset);
+ break;
+ }
+
+ DPRINT("read %s [0x%02x] -> 0x%02x\n", exynos4_i2c_get_regname(offset),
+ (unsigned int)offset, value);
+ return value;
+}
+
+static void exynos4210_i2c_write(void *opaque, hwaddr offset,
+ uint64_t value, unsigned size)
+{
+ Exynos4210I2CState *s = (Exynos4210I2CState *)opaque;
+ uint8_t v = value & 0xff;
+
+ DPRINT("write %s [0x%02x] <- 0x%02x\n", exynos4_i2c_get_regname(offset),
+ (unsigned int)offset, v);
+
+ switch (offset) {
+ case I2CCON_ADDR:
+ s->i2ccon = (v & ~I2CCON_INT_PEND) | (s->i2ccon & I2CCON_INT_PEND);
+ if ((s->i2ccon & I2CCON_INT_PEND) && !(v & I2CCON_INT_PEND)) {
+ s->i2ccon &= ~I2CCON_INT_PEND;
+ qemu_irq_lower(s->irq);
+ if (!(s->i2ccon & I2CCON_INTRS_EN)) {
+ s->i2cstat &= ~I2CSTAT_START_BUSY;
+ }
+
+ if (s->i2cstat & I2CSTAT_START_BUSY) {
+ if (s->scl_free) {
+ if (EXYNOS4_I2C_MODE(s->i2cstat) == I2CMODE_MASTER_Tx) {
+ exynos4210_i2c_data_send(s);
+ } else if (EXYNOS4_I2C_MODE(s->i2cstat) ==
+ I2CMODE_MASTER_Rx) {
+ exynos4210_i2c_data_receive(s);
+ }
+ } else {
+ s->i2ccon |= I2CCON_INT_PEND;
+ qemu_irq_raise(s->irq);
+ }
+ }
+ }
+ break;
+ case I2CSTAT_ADDR:
+ s->i2cstat =
+ (s->i2cstat & I2CSTAT_START_BUSY) | (v & ~I2CSTAT_START_BUSY);
+
+ if (!(s->i2cstat & I2CSTAT_OUTPUT_EN)) {
+ s->i2cstat &= ~I2CSTAT_START_BUSY;
+ s->scl_free = true;
+ qemu_irq_lower(s->irq);
+ break;
+ }
+
+ /* Nothing to do if in i2c slave mode */
+ if (!I2C_IN_MASTER_MODE(s->i2cstat)) {
+ break;
+ }
+
+ if (v & I2CSTAT_START_BUSY) {
+ s->i2cstat &= ~I2CSTAT_LAST_BIT;
+ s->i2cstat |= I2CSTAT_START_BUSY; /* Line is busy */
+ s->scl_free = false;
+
+ /* Generate start bit and send slave address */
+ if (i2c_start_transfer(s->bus, s->i2cds >> 1, s->i2cds & 0x1) &&
+ (s->i2ccon & I2CCON_ACK_GEN)) {
+ s->i2cstat |= I2CSTAT_LAST_BIT;
+ } else if (EXYNOS4_I2C_MODE(s->i2cstat) == I2CMODE_MASTER_Rx) {
+ exynos4210_i2c_data_receive(s);
+ }
+ exynos4210_i2c_raise_interrupt(s);
+ } else {
+ i2c_end_transfer(s->bus);
+ if (!(s->i2ccon & I2CCON_INT_PEND)) {
+ s->i2cstat &= ~I2CSTAT_START_BUSY;
+ }
+ s->scl_free = true;
+ }
+ break;
+ case I2CADD_ADDR:
+ if ((s->i2cstat & I2CSTAT_OUTPUT_EN) == 0) {
+ s->i2cadd = v;
+ }
+ break;
+ case I2CDS_ADDR:
+ if (s->i2cstat & I2CSTAT_OUTPUT_EN) {
+ s->i2cds = v;
+ s->scl_free = true;
+ if (EXYNOS4_I2C_MODE(s->i2cstat) == I2CMODE_MASTER_Tx &&
+ (s->i2cstat & I2CSTAT_START_BUSY) &&
+ !(s->i2ccon & I2CCON_INT_PEND)) {
+ exynos4210_i2c_data_send(s);
+ }
+ }
+ break;
+ case I2CLC_ADDR:
+ s->i2clc = v;
+ break;
+ default:
+ DPRINT("ERROR: Bad write offset 0x%x\n", (unsigned int)offset);
+ break;
+ }
+}
+
+static const MemoryRegionOps exynos4210_i2c_ops = {
+ .read = exynos4210_i2c_read,
+ .write = exynos4210_i2c_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const VMStateDescription exynos4210_i2c_vmstate = {
+ .name = "exynos4210.i2c",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT8(i2ccon, Exynos4210I2CState),
+ VMSTATE_UINT8(i2cstat, Exynos4210I2CState),
+ VMSTATE_UINT8(i2cds, Exynos4210I2CState),
+ VMSTATE_UINT8(i2cadd, Exynos4210I2CState),
+ VMSTATE_UINT8(i2clc, Exynos4210I2CState),
+ VMSTATE_BOOL(scl_free, Exynos4210I2CState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void exynos4210_i2c_reset(DeviceState *d)
+{
+ Exynos4210I2CState *s = EXYNOS4_I2C(d);
+
+ s->i2ccon = 0x00;
+ s->i2cstat = 0x00;
+ s->i2cds = 0xFF;
+ s->i2clc = 0x00;
+ s->i2cadd = 0xFF;
+ s->scl_free = true;
+}
+
+static int exynos4210_i2c_realize(SysBusDevice *sbd)
+{
+ DeviceState *dev = DEVICE(sbd);
+ Exynos4210I2CState *s = EXYNOS4_I2C(dev);
+
+ memory_region_init_io(&s->iomem, OBJECT(s), &exynos4210_i2c_ops, s,
+ TYPE_EXYNOS4_I2C, EXYNOS4_I2C_MEM_SIZE);
+ sysbus_init_mmio(sbd, &s->iomem);
+ sysbus_init_irq(sbd, &s->irq);
+ s->bus = i2c_init_bus(dev, "i2c");
+ return 0;
+}
+
+static void exynos4210_i2c_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ SysBusDeviceClass *sbdc = SYS_BUS_DEVICE_CLASS(klass);
+
+ dc->vmsd = &exynos4210_i2c_vmstate;
+ dc->reset = exynos4210_i2c_reset;
+ sbdc->init = exynos4210_i2c_realize;
+}
+
+static const TypeInfo exynos4210_i2c_type_info = {
+ .name = TYPE_EXYNOS4_I2C,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(Exynos4210I2CState),
+ .class_init = exynos4210_i2c_class_init,
+};
+
+static void exynos4210_i2c_register_types(void)
+{
+ type_register_static(&exynos4210_i2c_type_info);
+}
+
+type_init(exynos4210_i2c_register_types)
Code Review / kvmfornfv.git / blobdiff