* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
+ * SMBus block read/write support added by Stefan Roese:
+ * Copyright (C) 2016 Stefan Roese <sr@denx.de>
+ *
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <i2c.h>
+#include <pci.h>
#include <asm/io.h>
-#include <asm/arch/pch.h>
-int intel_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
+/* 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)
{
- return -ENOSYS;
+ 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;
}
-int intel_i2c_probe_chip(struct udevice *bus, uint chip_addr, uint chip_flags)
+static int smbus_wait_until_done(u32 base)
{
- return -ENOSYS;
+ 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;
}
-int intel_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+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 intel_i2c_probe(struct udevice *dev)
+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));
+
/*
- * So far this is just setup code for ivybridge SMbus. When we have
- * a full I2C driver this may need to be moved, generalised or made
- * dependant on a particular compatible string.
- *
- * Set SMBus I/O base
+ * We expect either two messages (one with an offset and one with the
+ * actucal data) or one message (just data)
*/
- dm_pci_write_config32(dev, SMB_BASE,
- SMBUS_IO_BASE | PCI_BASE_ADDRESS_SPACE_IO);
+ 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);
+ u32 base;
+
+ /* Save base address from PCI BAR */
+ priv->base = (u32)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);
- /* Set SMBus I/O space enable. */
- dm_pci_write_config16(dev, PCI_COMMAND, PCI_COMMAND_IO);
+ /* Disable interrupts */
+ outb(inb(base + SMBHSTCTL) & ~SMBHSTCNT_INTREN, base + SMBHSTCTL);
- /* Disable interrupt generation. */
- outb(0, SMBUS_IO_BASE + SMBHSTCTL);
+ /* Set 32-byte data buffer mode */
+ outb(inb(base + SMBAUXCTL) | SMBAUXCTL_E32B, base + SMBAUXCTL);
- /* Clear any lingering errors, so transactions can run. */
- outb(inb(SMBUS_IO_BASE + SMBHSTSTAT), SMBUS_IO_BASE + SMBHSTSTAT);
- debug("SMBus controller enabled\n");
+ 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;
}
.id = UCLASS_I2C,
.of_match = intel_i2c_ids,
.ops = &intel_i2c_ops,
+ .priv_auto_alloc_size = 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);
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