[3/8,v6] tpm2: Introduce TIS tpm core

diff --git a/drivers/tpm/tpm2_tis_core.c b/drivers/tpm/tpm2_tis_core.c
new file mode 100644
index 000000000000..ec8c730fe906
--- /dev/null
+++ b/drivers/tpm/tpm2_tis_core.c
@@ -0,0 +1,463 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020, Linaro Limited
+ *
+ * Based on the Linux TIS core interface and U-Boot original SPI TPM driver
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <tpm-v2.h>
+#include <linux/delay.h>
+#include <linux/unaligned/be_byteshift.h>
+#include "tpm_tis.h"
+
+int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+
+	if (size < 80)
+		return -ENOSPC;
+
+	return snprintf(buf, size,
+			"%s v2.0: VendorID 0x%04x, DeviceID 0x%04x, RevisionID 0x%02x [%s]",
+			dev->name, chip->vend_dev & 0xFFFF,
+			chip->vend_dev >> 16, chip->rid,
+			(chip->is_open ? "open" : "closed"));
+}
+
+/**
+ * tpm_tis_check_locality - Check the current TPM locality
+ *
+ * @dev: TPM device
+ * @loc:  locality
+ *
+ * Return: True if the tested locality matches
+ */
+static bool tpm_tis_check_locality(struct udevice *dev, int loc)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	u8 locality;
+
+	phy_ops->read_bytes(dev, TPM_ACCESS(loc), 1, &locality);
+	if ((locality & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID |
+	    TPM_ACCESS_REQUEST_USE)) ==
+	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
+		chip->locality = loc;
+		return true;
+	}
+
+	return false;
+}
+
+/**
+ * tpm_tis_request_locality - Request a locality from the TPM
+ *
+ * @dev:  TPM device
+ * @loc:  requested locality
+ *
+ * Return: 0 on success -1 on failure
+ */
+int tpm_tis_request_locality(struct udevice *dev, int loc)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	u8 buf = TPM_ACCESS_REQUEST_USE;
+	unsigned long start, stop;
+
+	if (tpm_tis_check_locality(dev, loc))
+		return 0;
+
+	phy_ops->write_bytes(dev, TPM_ACCESS(loc), 1, &buf);
+	start = get_timer(0);
+	stop = chip->timeout_a;
+	do {
+		if (tpm_tis_check_locality(dev, loc))
+			return 0;
+		mdelay(TPM_TIMEOUT_MS);
+	} while (get_timer(start) < stop);
+
+	return -1;
+}
+
+/**
+ * tpm_tis_status - Check the current device status
+ *
+ * @dev:   TPM device
+ * @status: return value of status
+ *
+ * Return: 0 on success, negative on failure
+ */
+static int tpm_tis_status(struct udevice *dev, u8 *status)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+
+	if (chip->locality < 0)
+		return -EINVAL;
+
+	phy_ops->read_bytes(dev, TPM_STS(chip->locality), 1, status);
+
+	if ((*status & TPM_STS_READ_ZERO)) {
+		log_err("TPM returned invalid status\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * tpm_tis_release_locality - Release the requested locality
+ *
+ * @dev: TPM device
+ * @loc:  requested locality
+ *
+ * Return: 0 on success, negative on failure
+ */
+int tpm_tis_release_locality(struct udevice *dev, int loc)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	u8 buf = TPM_ACCESS_ACTIVE_LOCALITY;
+	int ret;
+
+	if (chip->locality < 0)
+		return 0;
+
+	ret = phy_ops->write_bytes(dev, TPM_ACCESS(loc), 1, &buf);
+	chip->locality = -1;
+
+	return ret;
+}
+
+/**
+ * tpm_tis_wait_for_stat - Wait for TPM to become ready
+ *
+ * @dev:     TPM device
+ * @mask:    mask to match
+ * @timeout: timeout for retries
+ * @status:  current status
+ *
+ * Return: 0 on success, negative on failure
+ */
+static int tpm_tis_wait_for_stat(struct udevice *dev, u8 mask,
+				 unsigned long timeout, u8 *status)
+{
+	unsigned long start = get_timer(0);
+	unsigned long stop = timeout;
+	int ret;
+
+	do {
+		mdelay(TPM_TIMEOUT_MS);
+		ret = tpm_tis_status(dev, status);
+		if (ret)
+			return ret;
+
+		if ((*status & mask) == mask)
+			return 0;
+	} while (get_timer(start) < stop);
+
+	return -ETIMEDOUT;
+}
+
+/**
+ * tpm_tis_get_burstcount - Get the burstcount for the data FIFO
+ *
+ * @dev:        TPM device
+ * @burstcount: current burstcount
+ *
+ * Return: 0 on success, negative on failure
+ */
+static int tpm_tis_get_burstcount(struct udevice *dev, size_t *burstcount)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	unsigned long start, stop;
+	u32 burst;
+
+	if (chip->locality < 0)
+		return -EINVAL;
+
+	/* wait for burstcount */
+	start = get_timer(0);
+	/*
+	 * This is the TPMv2 defined timeout. Change this in case you want to
+	 * make the driver compatile to TPMv1
+	 */
+	stop = chip->timeout_a;
+	do {
+		phy_ops->read32(dev, TPM_STS(chip->locality), &burst);
+		*burstcount = (burst >> 8) & 0xFFFF;
+		if (*burstcount)
+			return 0;
+
+		mdelay(TPM_TIMEOUT_MS);
+	} while (get_timer(start) < stop);
+
+	return -ETIMEDOUT;
+}
+
+/**
+ * tpm_tis_ready - Cancel pending comands and get the device on a ready state
+ *
+ * @dev: TPM device
+ *
+ * Return: 0 on success, negative on failure
+ */
+static int tpm_tis_ready(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	u8 data = TPM_STS_COMMAND_READY;
+
+	/* This will cancel any pending commands */
+	return phy_ops->write_bytes(dev, TPM_STS(chip->locality), 1, &data);
+}
+
+int tpm_tis_send(struct udevice *dev, const u8 *buf, size_t len)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	size_t burstcnt, wr_size, sent = 0;
+	u8 data = TPM_STS_GO;
+	u8 status;
+	int ret;
+
+	if (!chip)
+		return -ENODEV;
+
+	ret = tpm_tis_request_locality(dev, 0);
+	if (ret < 0)
+		return -EBUSY;
+
+	ret = tpm_tis_status(dev, &status);
+	if (ret)
+		goto release_locality;
+
+	if (!(status & TPM_STS_COMMAND_READY)) {
+		ret = tpm_tis_ready(dev);
+		if (ret) {
+			log_err("Can't cancel previous TPM operation\n");
+			goto release_locality;
+		}
+		ret = tpm_tis_wait_for_stat(dev, TPM_STS_COMMAND_READY,
+					    chip->timeout_b, &status);
+		if (ret) {
+			log_err("TPM not ready\n");
+			goto release_locality;
+		}
+	}
+
+	while (len > 0) {
+		ret = tpm_tis_get_burstcount(dev, &burstcnt);
+		if (ret)
+			goto release_locality;
+
+		wr_size = min(len, burstcnt);
+		ret = phy_ops->write_bytes(dev, TPM_DATA_FIFO(chip->locality),
+					   wr_size, buf + sent);
+		if (ret < 0)
+			goto release_locality;
+
+		ret = tpm_tis_wait_for_stat(dev, TPM_STS_VALID,
+					    chip->timeout_c, &status);
+		if (ret)
+			goto release_locality;
+
+		sent += wr_size;
+		len -= wr_size;
+		/* make sure the TPM expects more data */
+		if (len && !(status & TPM_STS_DATA_EXPECT)) {
+			ret = -EIO;
+			goto release_locality;
+		}
+	}
+
+	/*
+	 * Make a final check ensuring everything is ok and the TPM expects no
+	 * more data
+	 */
+	ret = tpm_tis_wait_for_stat(dev, TPM_STS_VALID, chip->timeout_c,
+				    &status);
+	if (ret)
+		goto release_locality;
+
+	if (status & TPM_STS_DATA_EXPECT) {
+		ret = -EIO;
+		goto release_locality;
+	}
+
+	ret = phy_ops->write_bytes(dev, TPM_STS(chip->locality), 1, &data);
+	if (ret)
+		goto release_locality;
+
+	return sent;
+
+release_locality:
+	tpm_tis_ready(dev);
+	tpm_tis_release_locality(dev, chip->locality);
+
+	return ret;
+}
+
+static int tpm_tis_recv_data(struct udevice *dev, u8 *buf, size_t count)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	int size = 0, len, ret;
+	size_t burstcnt;
+	u8 status;
+
+	while (size < count &&
+	       tpm_tis_wait_for_stat(dev, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
+				     chip->timeout_c, &status) == 0) {
+		ret = tpm_tis_get_burstcount(dev, &burstcnt);
+		if (ret)
+			return ret;
+
+		len = min_t(int, burstcnt, count - size);
+		ret = phy_ops->read_bytes(dev, TPM_DATA_FIFO(chip->locality),
+					  len, buf + size);
+		if (ret < 0)
+			return ret;
+
+		size += len;
+	}
+
+	return size;
+}
+
+/**
+ * tpm_tis_recv - Receive data from a device
+ *
+ * @dev:  TPM device
+ * @buf:  buffer to copy data
+ * @size: buffer size
+ *
+ * Return: bytes read or negative on failure
+ */
+int tpm_tis_recv(struct udevice *dev, u8 *buf, size_t count)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	int size, expected;
+
+	if (count < TPM_HEADER_SIZE)
+		return -E2BIG;
+
+	size = tpm_tis_recv_data(dev, buf, TPM_HEADER_SIZE);
+	if (size < TPM_HEADER_SIZE) {
+		log_err("TPM error, unable to read header\n");
+		goto out;
+	}
+
+	expected = get_unaligned_be32(buf + TPM_CMD_COUNT_OFFSET);
+	if (expected > count) {
+		size = -EIO;
+		log_warning("Too much data: %d > %zu\n", expected, count);
+		goto out;
+	}
+
+	size += tpm_tis_recv_data(dev, &buf[TPM_HEADER_SIZE],
+				   expected - TPM_HEADER_SIZE);
+	if (size < expected) {
+		log(LOGC_NONE, LOGL_ERR,
+		    "TPM error, unable to read remaining bytes of result\n");
+		size = -EIO;
+		goto out;
+	}
+
+out:
+	tpm_tis_ready(dev);
+	/* acquired in tpm_tis_send */
+	tpm_tis_release_locality(dev, chip->locality);
+
+	return size;
+}
+
+int tpm_tis_cleanup(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+
+	tpm_tis_ready(dev);
+	tpm_tis_release_locality(dev, chip->locality);
+
+	return 0;
+}
+
+int tpm_tis_open(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	int ret;
+
+	if (chip->is_open)
+		return -EBUSY;
+
+	ret = tpm_tis_request_locality(dev, 0);
+	if (!ret)
+		chip->is_open = 1;
+
+	return ret;
+}
+
+void tpm_tis_ops_register(struct udevice *dev, struct tpm_tis_phy_ops *ops)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+
+	chip->phy_ops = ops;
+}
+
+static bool tis_check_ops(struct tpm_tis_phy_ops *phy_ops)
+{
+	if (!phy_ops || !phy_ops->read_bytes || !phy_ops->write_bytes ||
+	    !phy_ops->read32 || !phy_ops->write32)
+		return false;
+
+	return true;
+}
+
+int tpm_tis_init(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	struct tpm_tis_phy_ops *phy_ops = chip->phy_ops;
+	int ret;
+	u32 tmp;
+
+	if (!tis_check_ops(phy_ops)) {
+		log_err("Driver bug. No bus ops defined\n");
+		return -1;
+	}
+	ret = tpm_tis_request_locality(dev, 0);
+	if (ret)
+		return ret;
+
+	chip->timeout_a = TIS_SHORT_TIMEOUT_MS;
+	chip->timeout_b = TIS_LONG_TIMEOUT_MS;
+	chip->timeout_c = TIS_SHORT_TIMEOUT_MS;
+	chip->timeout_d = TIS_SHORT_TIMEOUT_MS;
+
+	/* Disable interrupts */
+	phy_ops->read32(dev, TPM_INT_ENABLE(chip->locality), &tmp);
+	tmp |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
+	       TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
+	tmp &= ~TPM_GLOBAL_INT_ENABLE;
+	phy_ops->write32(dev, TPM_INT_ENABLE(chip->locality), tmp);
+
+	phy_ops->read_bytes(dev, TPM_RID(chip->locality), 1, &chip->rid);
+	phy_ops->read32(dev, TPM_DID_VID(chip->locality), &chip->vend_dev);
+
+	return tpm_tis_release_locality(dev, chip->locality);
+}
+
+int tpm_tis_close(struct udevice *dev)
+{
+	struct tpm_chip *chip = dev_get_priv(dev);
+	int ret = 0;
+
+	if (chip->is_open) {
+		ret = tpm_tis_release_locality(dev, chip->locality);
+		chip->is_open = 0;
+	}
+
+	return ret;
+}
diff --git a/drivers/tpm/tpm_tis.h b/drivers/tpm/tpm_tis.h
index 2a160fe05c9a..7a69bace6828 100644
--- a/drivers/tpm/tpm_tis.h
+++ b/drivers/tpm/tpm_tis.h
@@ -21,6 +21,65 @@ 
 #include <linux/compiler.h>
 #include <linux/types.h>
 
+/**
+ * struct tpm_tis_phy_ops - low-level TPM bus operations
+ */
+struct tpm_tis_phy_ops {
+	/* read_bytes() - Read a number of bytes from the device
+	 *
+	 * @udev:   TPM device
+	 * @addr:   offset from device base
+	 * @len:    len to read
+	 * @result: data read
+	 */
+	int (*read_bytes)(struct udevice *udev, u32 addr, u16 len,
+			  u8 *result);
+	/* write_bytes() - Read a number of bytes from the device
+	 *
+	 * @udev:   TPM device
+	 * @addr:   offset from device base
+	 * @len:    len to read
+	 * @value:  data to write
+	 */
+	int (*write_bytes)(struct udevice *udev, u32 addr, u16 len,
+			   const u8 *value);
+	/* read32() - Read a 32bit value of the device
+	 *
+	 * @udev:   TPM device
+	 * @addr:   offset from device base
+	 * @result: data read
+	 */
+	int (*read32)(struct udevice *udev, u32 addr, u32 *result);
+	/* write32() - write a 32bit value to the device
+	 *
+	 * @udev: TPM device
+	 * @addr: offset from device base
+	 * @src:  data to write
+	 */
+	int (*write32)(struct udevice *udev, u32 addr, u32 src);
+};
+
+enum tis_int_flags {
+	TPM_GLOBAL_INT_ENABLE = 0x80000000,
+	TPM_INTF_BURST_COUNT_STATIC = 0x100,
+	TPM_INTF_CMD_READY_INT = 0x080,
+	TPM_INTF_INT_EDGE_FALLING = 0x040,
+	TPM_INTF_INT_EDGE_RISING = 0x020,
+	TPM_INTF_INT_LEVEL_LOW = 0x010,
+	TPM_INTF_INT_LEVEL_HIGH = 0x008,
+	TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
+	TPM_INTF_STS_VALID_INT = 0x002,
+	TPM_INTF_DATA_AVAIL_INT = 0x001,
+};
+
+#define TPM_ACCESS(l)                   (0x0000 | ((l) << 12))
+#define TPM_INT_ENABLE(l)               (0x0008 | ((l) << 12))
+#define TPM_STS(l)                      (0x0018 | ((l) << 12))
+#define TPM_DATA_FIFO(l)                (0x0024 | ((l) << 12))
+#define TPM_DID_VID(l)                  (0x0f00 | ((l) << 12))
+#define TPM_RID(l)                      (0x0f04 | ((l) << 12))
+#define TPM_INTF_CAPS(l)                (0x0014 | ((l) << 12))
+
 enum tpm_timeout {
 	TPM_TIMEOUT_MS			= 5,
 	TIS_SHORT_TIMEOUT_MS		= 750,
@@ -43,6 +102,7 @@  struct tpm_chip {
 	u8 rid;
 	unsigned long timeout_a, timeout_b, timeout_c, timeout_d;  /* msec */
 	ulong chip_type;
+	struct tpm_tis_phy_ops *phy_ops;
 };
 
 struct tpm_input_header {
@@ -130,4 +190,72 @@  enum tis_status {
 };
 #endif
 
+/**
+ * tpm_tis_open - Open the device and request locality 0
+ *
+ * @dev:  TPM device
+ *
+ * Return: 0 on success, negative on failure
+ */
+int tpm_tis_open(struct udevice *udev);
+/**
+ * tpm_tis_close - Close the device and release locality
+ *
+ * @dev:  TPM device
+ *
+ * Return: 0 on success, negative on failure
+ */
+int tpm_tis_close(struct udevice *udev);
+/** tpm_tis_cleanup - Get the device in ready state and release locality
+ *
+ * @dev:  TPM device
+ *
+ * Return: always 0
+ */
+int tpm_tis_cleanup(struct udevice *udev);
+/**
+ * tpm_tis_send - send data to the device
+ *
+ * @dev:  TPM device
+ * @buf:  buffer to send
+ * @len:  size of the buffer
+ *
+ * Return: number of bytes sent or negative on failure
+ */
+int tpm_tis_send(struct udevice *udev, const u8 *buf, size_t len);
+/**
+ * tpm_tis_recv_data - Receive data from a device. Wrapper for tpm_tis_recv
+ *
+ * @dev:  TPM device
+ * @buf:  buffer to copy data
+ * @size: buffer size
+ *
+ * Return: bytes read or negative on failure
+ */
+int tpm_tis_recv(struct udevice *udev, u8 *buf, size_t count);
+/**
+ * tpm_tis_get_desc - Get the TPM description
+ *
+ * @dev:  TPM device
+ * @buf:  buffer to fill data
+ * @size: buffer size
+ *
+ * @Return: Number of characters written (or would have been written) in buffer
+ */
+int tpm_tis_get_desc(struct udevice *udev, char *buf, int size);
+/**
+ * tpm_tis_init - inititalize the device
+ *
+ * @dev:  TPM device
+ *
+ * Return: 0 on success, negative on failure
+ */
+int tpm_tis_init(struct udevice *udev);
+/**
+ * tpm_tis_ops_register - register the PHY ops for the device
+ *
+ * @dev: TPM device
+ * @ops: tpm_tis_phy_ops ops for the device
+ */
+void tpm_tis_ops_register(struct udevice *udev, struct tpm_tis_phy_ops *ops);
 #endif
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 13b3db67c60f..e6b68769f3ff 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -396,6 +396,7 @@  enum {
 	TPM_STS_DATA_EXPECT		= 1 << 3,
 	TPM_STS_SELF_TEST_DONE		= 1 << 2,
 	TPM_STS_RESPONSE_RETRY		= 1 << 1,
+	TPM_STS_READ_ZERO               = 0x23
 };
 
 enum {