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-rw-r--r--hw/i2c/mpc_i2c.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/hw/i2c/mpc_i2c.c b/hw/i2c/mpc_i2c.c
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--- /dev/null
+++ b/hw/i2c/mpc_i2c.c
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+/*
+ * Copyright (C) 2014 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author: Amit Tomar, <Amit.Tomar@freescale.com>
+ *
+ * Description:
+ * This file is derived from IMX I2C controller,
+ * by Jean-Christophe DUBOIS .
+ *
+ * Thanks to Scott Wood and Alexander Graf for their kind help on this.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2 or later,
+ * as published by the Free Software Foundation.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/i2c/i2c.h"
+#include "qemu/log.h"
+#include "hw/sysbus.h"
+
+/* #define DEBUG_I2C */
+
+#ifdef DEBUG_I2C
+#define DPRINTF(fmt, ...) \
+ do { fprintf(stderr, "mpc_i2c[%s]: " fmt, __func__, ## __VA_ARGS__); \
+ } while (0)
+#else
+#define DPRINTF(fmt, ...) do {} while (0)
+#endif
+
+#define TYPE_MPC_I2C "mpc-i2c"
+#define MPC_I2C(obj) \
+ OBJECT_CHECK(MPCI2CState, (obj), TYPE_MPC_I2C)
+
+#define MPC_I2C_ADR 0x00
+#define MPC_I2C_FDR 0x04
+#define MPC_I2C_CR 0x08
+#define MPC_I2C_SR 0x0c
+#define MPC_I2C_DR 0x10
+#define MPC_I2C_DFSRR 0x14
+
+#define CCR_MEN (1 << 7)
+#define CCR_MIEN (1 << 6)
+#define CCR_MSTA (1 << 5)
+#define CCR_MTX (1 << 4)
+#define CCR_TXAK (1 << 3)
+#define CCR_RSTA (1 << 2)
+#define CCR_BCST (1 << 0)
+
+#define CSR_MCF (1 << 7)
+#define CSR_MAAS (1 << 6)
+#define CSR_MBB (1 << 5)
+#define CSR_MAL (1 << 4)
+#define CSR_SRW (1 << 2)
+#define CSR_MIF (1 << 1)
+#define CSR_RXAK (1 << 0)
+
+#define CADR_MASK 0xFE
+#define CFDR_MASK 0x3F
+#define CCR_MASK 0xFC
+#define CSR_MASK 0xED
+#define CDR_MASK 0xFF
+
+#define CYCLE_RESET 0xFF
+
+typedef struct MPCI2CState {
+ SysBusDevice parent_obj;
+
+ I2CBus *bus;
+ qemu_irq irq;
+ MemoryRegion iomem;
+
+ uint8_t address;
+ uint8_t adr;
+ uint8_t fdr;
+ uint8_t cr;
+ uint8_t sr;
+ uint8_t dr;
+ uint8_t dfssr;
+} MPCI2CState;
+
+static bool mpc_i2c_is_enabled(MPCI2CState *s)
+{
+ return s->cr & CCR_MEN;
+}
+
+static bool mpc_i2c_is_master(MPCI2CState *s)
+{
+ return s->cr & CCR_MSTA;
+}
+
+static bool mpc_i2c_direction_is_tx(MPCI2CState *s)
+{
+ return s->cr & CCR_MTX;
+}
+
+static bool mpc_i2c_irq_pending(MPCI2CState *s)
+{
+ return s->sr & CSR_MIF;
+}
+
+static bool mpc_i2c_irq_is_enabled(MPCI2CState *s)
+{
+ return s->cr & CCR_MIEN;
+}
+
+static void mpc_i2c_reset(DeviceState *dev)
+{
+ MPCI2CState *i2c = MPC_I2C(dev);
+
+ i2c->address = 0xFF;
+ i2c->adr = 0x00;
+ i2c->fdr = 0x00;
+ i2c->cr = 0x00;
+ i2c->sr = 0x81;
+ i2c->dr = 0x00;
+}
+
+static void mpc_i2c_irq(MPCI2CState *s)
+{
+ bool irq_active = false;
+
+ if (mpc_i2c_is_enabled(s) && mpc_i2c_irq_is_enabled(s)
+ && mpc_i2c_irq_pending(s)) {
+ irq_active = true;
+ }
+
+ if (irq_active) {
+ qemu_irq_raise(s->irq);
+ } else {
+ qemu_irq_lower(s->irq);
+ }
+}
+
+static void mpc_i2c_soft_reset(MPCI2CState *s)
+{
+ /* This is a soft reset. ADR is preserved during soft resets */
+ uint8_t adr = s->adr;
+ mpc_i2c_reset(DEVICE(s));
+ s->adr = adr;
+}
+
+static void mpc_i2c_address_send(MPCI2CState *s)
+{
+ /* if returns non zero slave address is not right */
+ if (i2c_start_transfer(s->bus, s->dr >> 1, s->dr & (0x01))) {
+ s->sr |= CSR_RXAK;
+ } else {
+ s->address = s->dr;
+ s->sr &= ~CSR_RXAK;
+ s->sr |= CSR_MCF; /* Set after Byte Transfer is completed */
+ s->sr |= CSR_MIF; /* Set after Byte Transfer is completed */
+ mpc_i2c_irq(s);
+ }
+}
+
+static void mpc_i2c_data_send(MPCI2CState *s)
+{
+ if (i2c_send(s->bus, s->dr)) {
+ /* End of transfer */
+ s->sr |= CSR_RXAK;
+ i2c_end_transfer(s->bus);
+ } else {
+ s->sr &= ~CSR_RXAK;
+ s->sr |= CSR_MCF; /* Set after Byte Transfer is completed */
+ s->sr |= CSR_MIF; /* Set after Byte Transfer is completed */
+ mpc_i2c_irq(s);
+ }
+}
+
+static void mpc_i2c_data_recive(MPCI2CState *s)
+{
+ int ret;
+ /* get the next byte */
+ ret = i2c_recv(s->bus);
+ if (ret >= 0) {
+ s->sr |= CSR_MCF; /* Set after Byte Transfer is completed */
+ s->sr |= CSR_MIF; /* Set after Byte Transfer is completed */
+ mpc_i2c_irq(s);
+ } else {
+ DPRINTF("read failed for device");
+ ret = 0xff;
+ }
+ s->dr = ret;
+}
+
+static uint64_t mpc_i2c_read(void *opaque, hwaddr addr, unsigned size)
+{
+ MPCI2CState *s = opaque;
+ uint8_t value;
+
+ switch (addr) {
+ case MPC_I2C_ADR:
+ value = s->adr;
+ break;
+ case MPC_I2C_FDR:
+ value = s->fdr;
+ break;
+ case MPC_I2C_CR:
+ value = s->cr;
+ break;
+ case MPC_I2C_SR:
+ value = s->sr;
+ break;
+ case MPC_I2C_DR:
+ value = s->dr;
+ if (mpc_i2c_is_master(s)) { /* master mode */
+ if (mpc_i2c_direction_is_tx(s)) {
+ DPRINTF("MTX is set not in recv mode\n");
+ } else {
+ mpc_i2c_data_recive(s);
+ }
+ }
+ break;
+ default:
+ value = 0;
+ DPRINTF("ERROR: Bad read addr 0x%x\n", (unsigned int)addr);
+ break;
+ }
+
+ DPRINTF("%s: addr " TARGET_FMT_plx " %02" PRIx32 "\n", __func__,
+ addr, value);
+ return (uint64_t)value;
+}
+
+static void mpc_i2c_write(void *opaque, hwaddr addr,
+ uint64_t value, unsigned size)
+{
+ MPCI2CState *s = opaque;
+
+ DPRINTF("%s: addr " TARGET_FMT_plx " val %08" PRIx64 "\n", __func__,
+ addr, value);
+ switch (addr) {
+ case MPC_I2C_ADR:
+ s->adr = value & CADR_MASK;
+ break;
+ case MPC_I2C_FDR:
+ s->fdr = value & CFDR_MASK;
+ break;
+ case MPC_I2C_CR:
+ if (mpc_i2c_is_enabled(s) && ((value & CCR_MEN) == 0)) {
+ mpc_i2c_soft_reset(s);
+ break;
+ }
+ /* normal write */
+ s->cr = value & CCR_MASK;
+ if (mpc_i2c_is_master(s)) { /* master mode */
+ /* set the bus to busy after master is set as per RM */
+ s->sr |= CSR_MBB;
+ } else {
+ /* bus is not busy anymore */
+ s->sr &= ~CSR_MBB;
+ /* Reset the address for fresh write/read cycle */
+ if (s->address != CYCLE_RESET) {
+ i2c_end_transfer(s->bus);
+ s->address = CYCLE_RESET;
+ }
+ }
+ /* For restart end the onging transfer */
+ if (s->cr & CCR_RSTA) {
+ if (s->address != CYCLE_RESET) {
+ s->address = CYCLE_RESET;
+ i2c_end_transfer(s->bus);
+ s->cr &= ~CCR_RSTA;
+ }
+ }
+ break;
+ case MPC_I2C_SR:
+ s->sr = value & CSR_MASK;
+ /* Lower the interrupt */
+ if (!(s->sr & CSR_MIF) || !(s->sr & CSR_MAL)) {
+ mpc_i2c_irq(s);
+ }
+ break;
+ case MPC_I2C_DR:
+ /* if the device is not enabled, nothing to do */
+ if (!mpc_i2c_is_enabled(s)) {
+ break;
+ }
+ s->dr = value & CDR_MASK;
+ if (mpc_i2c_is_master(s)) { /* master mode */
+ if (s->address == CYCLE_RESET) {
+ mpc_i2c_address_send(s);
+ } else {
+ mpc_i2c_data_send(s);
+ }
+ }
+ break;
+ case MPC_I2C_DFSRR:
+ s->dfssr = value;
+ break;
+ default:
+ DPRINTF("ERROR: Bad write addr 0x%x\n", (unsigned int)addr);
+ break;
+ }
+}
+
+static const MemoryRegionOps i2c_ops = {
+ .read = mpc_i2c_read,
+ .write = mpc_i2c_write,
+ .valid.max_access_size = 1,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static const VMStateDescription mpc_i2c_vmstate = {
+ .name = TYPE_MPC_I2C,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT8(address, MPCI2CState),
+ VMSTATE_UINT8(adr, MPCI2CState),
+ VMSTATE_UINT8(fdr, MPCI2CState),
+ VMSTATE_UINT8(cr, MPCI2CState),
+ VMSTATE_UINT8(sr, MPCI2CState),
+ VMSTATE_UINT8(dr, MPCI2CState),
+ VMSTATE_UINT8(dfssr, MPCI2CState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void mpc_i2c_realize(DeviceState *dev, Error **errp)
+{
+ MPCI2CState *i2c = MPC_I2C(dev);
+ sysbus_init_irq(SYS_BUS_DEVICE(dev), &i2c->irq);
+ memory_region_init_io(&i2c->iomem, OBJECT(i2c), &i2c_ops, i2c,
+ "mpc-i2c", 0x14);
+ sysbus_init_mmio(SYS_BUS_DEVICE(dev), &i2c->iomem);
+ i2c->bus = i2c_init_bus(DEVICE(dev), "i2c");
+}
+
+static void mpc_i2c_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->vmsd = &mpc_i2c_vmstate ;
+ dc->reset = mpc_i2c_reset;
+ dc->realize = mpc_i2c_realize;
+ dc->desc = "MPC I2C Controller";
+}
+
+static const TypeInfo mpc_i2c_type_info = {
+ .name = TYPE_MPC_I2C,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(MPCI2CState),
+ .class_init = mpc_i2c_class_init,
+};
+
+static void mpc_i2c_register_types(void)
+{
+ type_register_static(&mpc_i2c_type_info);
+}
+
+type_init(mpc_i2c_register_types)
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