hw/i2c/mpc_i2c.c - qemu - Git at Google

 /*
  * 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 "hw/irq.h"
 #include "qemu/log.h"
 #include "qemu/module.h"
 #include "hw/sysbus.h"
 #include "migration/vmstate.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(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)
	/*
	* 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 "hw/irq.h"
	#include "qemu/log.h"
	#include "qemu/module.h"
	#include "hw/sysbus.h"
	#include "migration/vmstate.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(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)