[J-u-boot.git] / drivers / i2c / intel_i2c.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (c) 2015 Google, Inc
 * Written by Simon Glass <[email protected]>
 *
 * SMBus block read/write support added by Stefan Roese:
 * Copyright (C) 2016 Stefan Roese <[email protected]>
 */

#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <log.h>
#include <pci.h>
#include <asm/io.h>

/* PCI Configuration Space (D31:F3): SMBus */
#define SMB_BASE		0x20
#define HOSTC			0x40
#define  HST_EN			(1 << 0)
#define SMB_RCV_SLVA		0x09

/* SMBus I/O bits. */
#define SMBHSTSTAT		0x0
#define SMBHSTCTL		0x2
#define SMBHSTCMD		0x3
#define SMBXMITADD		0x4
#define SMBHSTDAT0		0x5
#define SMBHSTDAT1		0x6
#define SMBBLKDAT		0x7
#define SMBTRNSADD		0x9
#define SMBSLVDATA		0xa
#define SMBAUXCTL		0xd
#define SMLINK_PIN_CTL		0xe
#define SMBUS_PIN_CTL		0xf

/* I801 Hosts Status register bits */
#define SMBHSTSTS_BYTE_DONE	0x80
#define SMBHSTSTS_INUSE_STS	0x40
#define SMBHSTSTS_SMBALERT_STS	0x20
#define SMBHSTSTS_FAILED	0x10
#define SMBHSTSTS_BUS_ERR	0x08
#define SMBHSTSTS_DEV_ERR	0x04
#define SMBHSTSTS_INTR		0x02
#define SMBHSTSTS_HOST_BUSY	0x01

/* I801 Host Control register bits */
#define SMBHSTCNT_INTREN	0x01
#define SMBHSTCNT_KILL		0x02
#define SMBHSTCNT_LAST_BYTE	0x20
#define SMBHSTCNT_START		0x40
#define SMBHSTCNT_PEC_EN	0x80	/* ICH3 and later */

/* Auxiliary control register bits, ICH4+ only */
#define SMBAUXCTL_CRC		1
#define SMBAUXCTL_E32B		2

#define SMBUS_TIMEOUT	100	/* 100 ms */

struct intel_i2c {
	u32 base;
	int running;
};

static int smbus_wait_until_ready(u32 base)
{
	unsigned long ts;
	u8 byte;

	ts = get_timer(0);
	do {
		byte = inb(base + SMBHSTSTAT);
		if (!(byte & 1))
			return 0;
	} while (get_timer(ts) < SMBUS_TIMEOUT);

	return -ETIMEDOUT;
}

static int smbus_wait_until_done(u32 base)
{
	unsigned long ts;
	u8 byte;

	ts = get_timer(0);
	do {
		byte = inb(base + SMBHSTSTAT);
		if (!((byte & 1) || (byte & ~((1 << 6) | (1 << 0))) == 0))
			return 0;
	} while (get_timer(ts) < SMBUS_TIMEOUT);

	return -ETIMEDOUT;
}

static int smbus_block_read(u32 base, u8 dev, u8 *buffer,
			    int offset, int len)
{
	u8 buf_temp[32];
	int count;
	int i;

	debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
	      __func__, __LINE__, dev, offset, len);
	if (smbus_wait_until_ready(base) < 0)
		return -ETIMEDOUT;

	/* Setup transaction */

	/* Reset the data buffer index */
	inb(base + SMBHSTCTL);

	/* Set the device I'm talking too */
	outb(((dev & 0x7f) << 1) | 1, base + SMBXMITADD);
	/* Set the command/address... */
	outb(offset & 0xff, base + SMBHSTCMD);
	/* Set up for a block read */
	outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) | (0x5 << 2),
	     (base + SMBHSTCTL));
	/* Clear any lingering errors, so the transaction will run */
	outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);

	/* Start the command */
	outb((inb(base + SMBHSTCTL) | SMBHSTCNT_START), base + SMBHSTCTL);

	/* Poll for transaction completion */
	if (smbus_wait_until_done(base) < 0) {
		printf("SMBUS read transaction timeout (dev=0x%x)\n", dev);
		return -ETIMEDOUT;
	}

	count = inb(base + SMBHSTDAT0);
	debug("%s (%d): count=%d (len=%d)\n", __func__, __LINE__, count, len);
	if (count == 0) {
		debug("ERROR: len=0 on read\n");
		return -EIO;
	}

	if (count < len) {
		debug("ERROR: too few bytes read\n");
		return -EIO;
	}

	if (count > 32) {
		debug("ERROR: count=%d too high\n", count);
		return -EIO;
	}

	/* Read all available bytes from buffer */
	for (i = 0; i < count; i++)
		buf_temp[i] = inb(base + SMBBLKDAT);

	memcpy(buffer, buf_temp, len);

	/* Return results of transaction */
	if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
		return -EIO;

	return 0;
}

static int smbus_block_write(u32 base, u8 dev, u8 *buffer,
			     int offset, int len)
{
	int i;

	debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
	      __func__, __LINE__, dev, offset, len);
	if (smbus_wait_until_ready(base) < 0)
		return -ETIMEDOUT;

	/* Setup transaction */
	/* Set the device I'm talking too */
	outb(((dev & 0x7f) << 1) & ~0x01, base + SMBXMITADD);
	/* Set the command/address... */
	outb(offset, base + SMBHSTCMD);
	/* Set up for a block write */
	outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) | (0x5 << 2),
	     (base + SMBHSTCTL));
	/* Clear any lingering errors, so the transaction will run */
	outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);

	/* Write count in DAT0 register */
	outb(len, base + SMBHSTDAT0);

	/* Write data bytes... */
	for (i = 0; i < len; i++)
		outb(*buffer++, base + SMBBLKDAT);

	/* Start the command */
	outb((inb(base + SMBHSTCTL) | SMBHSTCNT_START), base + SMBHSTCTL);

	/* Poll for transaction completion */
	if (smbus_wait_until_done(base) < 0) {
		printf("SMBUS write transaction timeout (dev=0x%x)\n", dev);
		return -ETIMEDOUT;
	}

	/* Return results of transaction */
	if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
		return -EIO;

	return 0;
}

static int intel_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
{
	struct intel_i2c *i2c = dev_get_priv(bus);
	struct i2c_msg *dmsg, *omsg, dummy;

	debug("i2c_xfer: %d messages\n", nmsgs);

	memset(&dummy, 0, sizeof(struct i2c_msg));

	/*
	 * We expect either two messages (one with an offset and one with the
	 * actucal data) or one message (just data)
	 */
	if (nmsgs > 2 || nmsgs == 0) {
		debug("%s: Only one or two messages are supported", __func__);
		return -EIO;
	}

	omsg = nmsgs == 1 ? &dummy : msg;
	dmsg = nmsgs == 1 ? msg : msg + 1;

	if (dmsg->flags & I2C_M_RD)
		return smbus_block_read(i2c->base, dmsg->addr, &dmsg->buf[0],
					omsg->buf[0], dmsg->len);
	else
		return smbus_block_write(i2c->base, dmsg->addr, &dmsg->buf[1],
					 dmsg->buf[0], dmsg->len - 1);
}

static int intel_i2c_probe_chip(struct udevice *bus, uint chip_addr,
				uint chip_flags)
{
	struct intel_i2c *i2c = dev_get_priv(bus);
	u8 buf[4];

	return smbus_block_read(i2c->base, chip_addr, buf, 0, 1);
}

static int intel_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
	return 0;
}

static int intel_i2c_probe(struct udevice *dev)
{
	struct intel_i2c *priv = dev_get_priv(dev);
	ulong base;

	/* Save base address from PCI BAR */
	priv->base = (ulong)dm_pci_map_bar(dev, PCI_BASE_ADDRESS_4,
					   PCI_REGION_IO);
	base = priv->base;

	/* Set SMBus enable. */
	dm_pci_write_config8(dev, HOSTC, HST_EN);

	/* Disable interrupts */
	outb(inb(base + SMBHSTCTL) & ~SMBHSTCNT_INTREN, base + SMBHSTCTL);

	/* Set 32-byte data buffer mode */
	outb(inb(base + SMBAUXCTL) | SMBAUXCTL_E32B, base + SMBAUXCTL);

	return 0;
}

static int intel_i2c_bind(struct udevice *dev)
{
	static int num_cards __attribute__ ((section(".data")));
	char name[20];

	/* Create a unique device name for PCI type devices */
	if (device_is_on_pci_bus(dev)) {
		/*
		 * ToDo:
		 * Setting req_seq in the driver is probably not recommended.
		 * But without a DT alias the number is not configured. And
		 * using this driver is impossible for PCIe I2C devices.
		 * This can be removed, once a better (correct) way for this
		 * is found and implemented.
		 */
		dev->req_seq = num_cards;
		sprintf(name, "intel_i2c#%u", num_cards++);
		device_set_name(dev, name);
	}

	return 0;
}

static const struct dm_i2c_ops intel_i2c_ops = {
	.xfer		= intel_i2c_xfer,
	.probe_chip	= intel_i2c_probe_chip,
	.set_bus_speed	= intel_i2c_set_bus_speed,
};

static const struct udevice_id intel_i2c_ids[] = {
	{ .compatible = "intel,ich-i2c" },
	{ }
};

U_BOOT_DRIVER(intel_i2c) = {
	.name	= "i2c_intel",
	.id	= UCLASS_I2C,
	.of_match = intel_i2c_ids,
	.ops	= &intel_i2c_ops,
	.priv_auto	= sizeof(struct intel_i2c),
	.bind	= intel_i2c_bind,
	.probe	= intel_i2c_probe,
};

static struct pci_device_id intel_smbus_pci_supported[] = {
	/* Intel BayTrail SMBus on the PCI bus */
	{ PCI_VDEVICE(INTEL, 0x0f12) },
	/* Intel IvyBridge (Panther Point PCH) SMBus on the PCI bus */
	{ PCI_VDEVICE(INTEL, 0x1e22) },
	{},
};

U_BOOT_PCI_DEVICE(intel_i2c, intel_smbus_pci_supported);
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
abb0b01e SG	2	/*
	3	* Copyright (c) 2015 Google, Inc
	4	* Written by Simon Glass <[email protected]>
	5	*
ca6c5e03 SR	6	* SMBus block read/write support added by Stefan Roese:
ca6c5e03 SR	7	* Copyright (C) 2016 Stefan Roese <[email protected]>
abb0b01e SG	8	*/
	9
	10	#include <common.h>
	11	#include <dm.h>
	12	#include <i2c.h>
f7ae49fc	13	#include <log.h>
ca6c5e03	14	#include <pci.h>
abb0b01e SG	15	#include <asm/io.h>
abb0b01e SG	16
ca6c5e03 SR	17	/* PCI Configuration Space (D31:F3): SMBus */
	18	#define SMB_BASE 0x20
	19	#define HOSTC 0x40
	20	#define HST_EN (1 << 0)
	21	#define SMB_RCV_SLVA 0x09
	22
	23	/* SMBus I/O bits. */
	24	#define SMBHSTSTAT 0x0
	25	#define SMBHSTCTL 0x2
	26	#define SMBHSTCMD 0x3
	27	#define SMBXMITADD 0x4
	28	#define SMBHSTDAT0 0x5
	29	#define SMBHSTDAT1 0x6
	30	#define SMBBLKDAT 0x7
	31	#define SMBTRNSADD 0x9
	32	#define SMBSLVDATA 0xa
	33	#define SMBAUXCTL 0xd
	34	#define SMLINK_PIN_CTL 0xe
	35	#define SMBUS_PIN_CTL 0xf
	36
	37	/* I801 Hosts Status register bits */
	38	#define SMBHSTSTS_BYTE_DONE 0x80
	39	#define SMBHSTSTS_INUSE_STS 0x40
	40	#define SMBHSTSTS_SMBALERT_STS 0x20
	41	#define SMBHSTSTS_FAILED 0x10
	42	#define SMBHSTSTS_BUS_ERR 0x08
	43	#define SMBHSTSTS_DEV_ERR 0x04
	44	#define SMBHSTSTS_INTR 0x02
	45	#define SMBHSTSTS_HOST_BUSY 0x01
	46
	47	/* I801 Host Control register bits */
	48	#define SMBHSTCNT_INTREN 0x01
	49	#define SMBHSTCNT_KILL 0x02
	50	#define SMBHSTCNT_LAST_BYTE 0x20
	51	#define SMBHSTCNT_START 0x40
	52	#define SMBHSTCNT_PEC_EN 0x80 /* ICH3 and later */
	53
	54	/* Auxiliary control register bits, ICH4+ only */
	55	#define SMBAUXCTL_CRC 1
	56	#define SMBAUXCTL_E32B 2
	57
	58	#define SMBUS_TIMEOUT 100 /* 100 ms */
	59
	60	struct intel_i2c {
	61	u32 base;
	62	int running;
	63	};
	64
	65	static int smbus_wait_until_ready(u32 base)
abb0b01e	66	{
ca6c5e03 SR	67	unsigned long ts;
	68	u8 byte;
	69
	70	ts = get_timer(0);
	71	do {
	72	byte = inb(base + SMBHSTSTAT);
	73	if (!(byte & 1))
	74	return 0;
	75	} while (get_timer(ts) < SMBUS_TIMEOUT);
	76
	77	return -ETIMEDOUT;
abb0b01e SG	78	}
abb0b01e SG	79
ca6c5e03	80	static int smbus_wait_until_done(u32 base)
abb0b01e	81	{
ca6c5e03 SR	82	unsigned long ts;
	83	u8 byte;
	84
	85	ts = get_timer(0);
	86	do {
	87	byte = inb(base + SMBHSTSTAT);
	88	if (!((byte & 1) \|\| (byte & ~((1 << 6) \| (1 << 0))) == 0))
	89	return 0;
	90	} while (get_timer(ts) < SMBUS_TIMEOUT);
	91
	92	return -ETIMEDOUT;
abb0b01e SG	93	}
abb0b01e SG	94
ca6c5e03 SR	95	static int smbus_block_read(u32 base, u8 dev, u8 *buffer,
ca6c5e03 SR	96	int offset, int len)
abb0b01e	97	{
ca6c5e03 SR	98	u8 buf_temp[32];
	99	int count;
	100	int i;
	101
	102	debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
	103	__func__, __LINE__, dev, offset, len);
	104	if (smbus_wait_until_ready(base) < 0)
	105	return -ETIMEDOUT;
	106
	107	/* Setup transaction */
	108
	109	/* Reset the data buffer index */
	110	inb(base + SMBHSTCTL);
	111
	112	/* Set the device I'm talking too */
	113	outb(((dev & 0x7f) << 1) \| 1, base + SMBXMITADD);
	114	/* Set the command/address... */
	115	outb(offset & 0xff, base + SMBHSTCMD);
	116	/* Set up for a block read */
	117	outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) \| (0x5 << 2),
	118	(base + SMBHSTCTL));
	119	/* Clear any lingering errors, so the transaction will run */
	120	outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);
	121
	122	/* Start the command */
	123	outb((inb(base + SMBHSTCTL) \| SMBHSTCNT_START), base + SMBHSTCTL);
	124
	125	/* Poll for transaction completion */
	126	if (smbus_wait_until_done(base) < 0) {
	127	printf("SMBUS read transaction timeout (dev=0x%x)\n", dev);
	128	return -ETIMEDOUT;
	129	}
	130
	131	count = inb(base + SMBHSTDAT0);
	132	debug("%s (%d): count=%d (len=%d)\n", __func__, __LINE__, count, len);
	133	if (count == 0) {
	134	debug("ERROR: len=0 on read\n");
	135	return -EIO;
	136	}
	137
	138	if (count < len) {
	139	debug("ERROR: too few bytes read\n");
	140	return -EIO;
	141	}
	142
	143	if (count > 32) {
	144	debug("ERROR: count=%d too high\n", count);
	145	return -EIO;
	146	}
	147
	148	/* Read all available bytes from buffer */
	149	for (i = 0; i < count; i++)
	150	buf_temp[i] = inb(base + SMBBLKDAT);
	151
	152	memcpy(buffer, buf_temp, len);
	153
	154	/* Return results of transaction */
	155	if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
	156	return -EIO;
	157
abb0b01e SG	158	return 0;
	159	}
	160
ca6c5e03 SR	161	static int smbus_block_write(u32 base, u8 dev, u8 *buffer,
ca6c5e03 SR	162	int offset, int len)
abb0b01e	163	{
ca6c5e03 SR	164	int i;
	165
	166	debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
	167	__func__, __LINE__, dev, offset, len);
	168	if (smbus_wait_until_ready(base) < 0)
	169	return -ETIMEDOUT;
	170
	171	/* Setup transaction */
	172	/* Set the device I'm talking too */
	173	outb(((dev & 0x7f) << 1) & ~0x01, base + SMBXMITADD);
	174	/* Set the command/address... */
	175	outb(offset, base + SMBHSTCMD);
	176	/* Set up for a block write */
	177	outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) \| (0x5 << 2),
	178	(base + SMBHSTCTL));
	179	/* Clear any lingering errors, so the transaction will run */
	180	outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);
	181
	182	/* Write count in DAT0 register */
	183	outb(len, base + SMBHSTDAT0);
	184
	185	/* Write data bytes... */
	186	for (i = 0; i < len; i++)
	187	outb(*buffer++, base + SMBBLKDAT);
	188
	189	/* Start the command */
	190	outb((inb(base + SMBHSTCTL) \| SMBHSTCNT_START), base + SMBHSTCTL);
	191
	192	/* Poll for transaction completion */
	193	if (smbus_wait_until_done(base) < 0) {
	194	printf("SMBUS write transaction timeout (dev=0x%x)\n", dev);
	195	return -ETIMEDOUT;
	196	}
	197
	198	/* Return results of transaction */
	199	if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
	200	return -EIO;
	201
	202	return 0;
	203	}
	204
	205	static int intel_i2c_xfer(struct udevice bus, struct i2c_msg msg, int nmsgs)
	206	{
	207	struct intel_i2c *i2c = dev_get_priv(bus);
	208	struct i2c_msg dmsg, omsg, dummy;
	209
	210	debug("i2c_xfer: %d messages\n", nmsgs);
	211
	212	memset(&dummy, 0, sizeof(struct i2c_msg));
	213
0c7645bd	214	/*
ca6c5e03 SR	215	* We expect either two messages (one with an offset and one with the
ca6c5e03 SR	216	* actucal data) or one message (just data)
0c7645bd	217	*/
ca6c5e03 SR	218	if (nmsgs > 2 \|\| nmsgs == 0) {
	219	debug("%s: Only one or two messages are supported", __func__);
	220	return -EIO;
	221	}
	222
	223	omsg = nmsgs == 1 ? &dummy : msg;
	224	dmsg = nmsgs == 1 ? msg : msg + 1;
	225
	226	if (dmsg->flags & I2C_M_RD)
	227	return smbus_block_read(i2c->base, dmsg->addr, &dmsg->buf[0],
	228	omsg->buf[0], dmsg->len);
	229	else
	230	return smbus_block_write(i2c->base, dmsg->addr, &dmsg->buf[1],
	231	dmsg->buf[0], dmsg->len - 1);
	232	}
	233
	234	static int intel_i2c_probe_chip(struct udevice *bus, uint chip_addr,
	235	uint chip_flags)
	236	{
	237	struct intel_i2c *i2c = dev_get_priv(bus);
	238	u8 buf[4];
	239
	240	return smbus_block_read(i2c->base, chip_addr, buf, 0, 1);
	241	}
	242
	243	static int intel_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
	244	{
	245	return 0;
	246	}
	247
	248	static int intel_i2c_probe(struct udevice *dev)
	249	{
	250	struct intel_i2c *priv = dev_get_priv(dev);
fac3e796	251	ulong base;
ca6c5e03 SR	252
ca6c5e03 SR	253	/* Save base address from PCI BAR */
fac3e796 SG	254	priv->base = (ulong)dm_pci_map_bar(dev, PCI_BASE_ADDRESS_4,
fac3e796 SG	255	PCI_REGION_IO);
ca6c5e03	256	base = priv->base;
0c7645bd SG	257
	258	/* Set SMBus enable. */
	259	dm_pci_write_config8(dev, HOSTC, HST_EN);
	260
ca6c5e03 SR	261	/* Disable interrupts */
ca6c5e03 SR	262	outb(inb(base + SMBHSTCTL) & ~SMBHSTCNT_INTREN, base + SMBHSTCTL);
0c7645bd	263
ca6c5e03 SR	264	/* Set 32-byte data buffer mode */
ca6c5e03 SR	265	outb(inb(base + SMBAUXCTL) \| SMBAUXCTL_E32B, base + SMBAUXCTL);
0c7645bd	266
ca6c5e03 SR	267	return 0;
	268	}
	269
	270	static int intel_i2c_bind(struct udevice *dev)
	271	{
	272	static int num_cards __attribute__ ((section(".data")));
	273	char name[20];
	274
	275	/* Create a unique device name for PCI type devices */
	276	if (device_is_on_pci_bus(dev)) {
	277	/*
	278	* ToDo:
	279	* Setting req_seq in the driver is probably not recommended.
	280	* But without a DT alias the number is not configured. And
	281	* using this driver is impossible for PCIe I2C devices.
	282	* This can be removed, once a better (correct) way for this
	283	* is found and implemented.
	284	*/
	285	dev->req_seq = num_cards;
	286	sprintf(name, "intel_i2c#%u", num_cards++);
	287	device_set_name(dev, name);
	288	}
0c7645bd	289
abb0b01e SG	290	return 0;
	291	}
	292
	293	static const struct dm_i2c_ops intel_i2c_ops = {
	294	.xfer = intel_i2c_xfer,
	295	.probe_chip = intel_i2c_probe_chip,
	296	.set_bus_speed = intel_i2c_set_bus_speed,
	297	};
	298
	299	static const struct udevice_id intel_i2c_ids[] = {
	300	{ .compatible = "intel,ich-i2c" },
	301	{ }
	302	};
	303
	304	U_BOOT_DRIVER(intel_i2c) = {
	305	.name = "i2c_intel",
	306	.id = UCLASS_I2C,
	307	.of_match = intel_i2c_ids,
abb0b01e	308	.ops = &intel_i2c_ops,
41575d8e	309	.priv_auto = sizeof(struct intel_i2c),
ca6c5e03	310	.bind = intel_i2c_bind,
abb0b01e SG	311	.probe = intel_i2c_probe,
abb0b01e SG	312	};
ca6c5e03 SR	313
	314	static struct pci_device_id intel_smbus_pci_supported[] = {
	315	/* Intel BayTrail SMBus on the PCI bus */
	316	{ PCI_VDEVICE(INTEL, 0x0f12) },
	317	/* Intel IvyBridge (Panther Point PCH) SMBus on the PCI bus */
	318	{ PCI_VDEVICE(INTEL, 0x1e22) },
	319	{},
	320	};
	321
	322	U_BOOT_PCI_DEVICE(intel_i2c, intel_smbus_pci_supported);