Move top level pc80 directory to drivers/

There is no reason for this to be a top level directory.
Some stuff from lib/ should also be moved to drivers/

Change-Id: I3c2d2e127f7215eadead029cfc7442c22b26814a
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/939
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

1 files changed, 548 insertions, 0 deletions

diff --git a/src/drivers/pc80/tpm.c b/src/drivers/pc80/tpm.c
new file mode 100644
index 0000000000..17e1ed702d
--- /dev/null
+++ b/src/drivers/pc80/tpm.c
@@ -0,0 +1,548 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2011 The Chromium OS Authors. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/*
+ * The code in this file has been heavily based on the article "Writing a TPM
+ * Device Driver" published on http://ptgmedia.pearsoncmg.com and the
+ * submission by Stefan Berger on Qemu-devel mailing list.
+ *
+ * One principal difference is that in the simplest config the other than 0
+ * TPM localities do not get mapped by some devices (for instance, by
+ * Infineon slb9635), so this driver provides access to locality 0 only.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <delay.h>
+#include <arch/io.h>
+#include <arch/byteorder.h>
+#include <console/console.h>
+#include <pc80/tpm.h>
+#include <cpu/x86/car.h>
+
+#define PREFIX "lpc_tpm: "
+
+/* coreboot wrapper for TPM driver (start) */
+#define	TPM_DEBUG(fmt, args...)		\
+	if (CONFIG_DEBUG_TPM) {		\
+		printk(BIOS_DEBUG, PREFIX);		\
+		printk(BIOS_DEBUG, fmt , ##args);	\
+	}
+#define printf(x...) printk(BIOS_ERR, x)
+
+#define min(a,b) MIN(a,b)
+#define max(a,b) MAX(a,b)
+#define readb(_a) (*(volatile unsigned char *) (_a))
+#define writeb(_v, _a) (*(volatile unsigned char *) (_a) = (_v))
+#define readl(_a) (*(volatile unsigned long *) (_a))
+#define writel(_v, _a) (*(volatile unsigned long *) (_a) = (_v))
+/* coreboot wrapper for TPM driver (end) */
+
+#ifndef CONFIG_TPM_TIS_BASE_ADDRESS
+/* Base TPM address standard for x86 systems */
+#define CONFIG_TPM_TIS_BASE_ADDRESS        0xfed40000
+#endif
+
+/* the macro accepts the locality value, but only locality 0 is operational */
+#define TIS_REG(LOCALITY, REG) \
+    (void *)(CONFIG_TPM_TIS_BASE_ADDRESS + (LOCALITY << 12) + REG)
+
+/* hardware registers' offsets */
+#define TIS_REG_ACCESS                 0x0
+#define TIS_REG_INT_ENABLE             0x8
+#define TIS_REG_INT_VECTOR             0xc
+#define TIS_REG_INT_STATUS             0x10
+#define TIS_REG_INTF_CAPABILITY        0x14
+#define TIS_REG_STS                    0x18
+#define TIS_REG_DATA_FIFO              0x24
+#define TIS_REG_DID_VID                0xf00
+#define TIS_REG_RID                    0xf04
+
+/* Some registers' bit field definitions */
+#define TIS_STS_VALID                  (1 << 7) /* 0x80 */
+#define TIS_STS_COMMAND_READY          (1 << 6) /* 0x40 */
+#define TIS_STS_TPM_GO                 (1 << 5) /* 0x20 */
+#define TIS_STS_DATA_AVAILABLE         (1 << 4) /* 0x10 */
+#define TIS_STS_EXPECT                 (1 << 3) /* 0x08 */
+#define TIS_STS_RESPONSE_RETRY         (1 << 1) /* 0x02 */
+
+#define TIS_ACCESS_TPM_REG_VALID_STS   (1 << 7) /* 0x80 */
+#define TIS_ACCESS_ACTIVE_LOCALITY     (1 << 5) /* 0x20 */
+#define TIS_ACCESS_BEEN_SEIZED         (1 << 4) /* 0x10 */
+#define TIS_ACCESS_SEIZE               (1 << 3) /* 0x08 */
+#define TIS_ACCESS_PENDING_REQUEST     (1 << 2) /* 0x04 */
+#define TIS_ACCESS_REQUEST_USE         (1 << 1) /* 0x02 */
+#define TIS_ACCESS_TPM_ESTABLISHMENT   (1 << 0) /* 0x01 */
+
+#define TIS_STS_BURST_COUNT_MASK       (0xffff)
+#define TIS_STS_BURST_COUNT_SHIFT      (8)
+
+/*
+ * Error value returned if a tpm register does not enter the expected state
+ * after continuous polling. No actual TPM register reading ever returns ~0,
+ * so this value is a safe error indication to be mixed with possible status
+ * register values.
+ */
+#define TPM_TIMEOUT_ERR			(~0)
+
+/* Error value returned on various TPM driver errors */
+#define TPM_DRIVER_ERR		(~0)
+
+ /* 1 second is plenty for anything TPM does.*/
+#define MAX_DELAY_US	(1000 * 1000)
+
+/* Retrieve burst count value out of the status register contents. */
+#define BURST_COUNT(status) ((u16)(((status) >> TIS_STS_BURST_COUNT_SHIFT) & \
+				   TIS_STS_BURST_COUNT_MASK))
+
+/*
+ * Structures defined below allow creating descriptions of TPM vendor/device
+ * ID information for run time discovery. The only device the system knows
+ * about at this time is Infineon slb9635
+ */
+struct device_name {
+	u16 dev_id;
+	const char * const dev_name;
+};
+
+struct vendor_name {
+	u16 vendor_id;
+	const char * vendor_name;
+	const struct device_name* dev_names;
+};
+
+static const struct device_name infineon_devices[] = {
+	{0xb, "SLB9635 TT 1.2"},
+	{0}
+};
+
+static const struct vendor_name vendor_names[] = {
+	{0x15d1, "Infineon", infineon_devices},
+};
+
+/*
+ * Cached vendor/device ID pair to indicate that the device has been already
+ * discovered
+ */
+static u32 vendor_dev_id CAR_GLOBAL;
+
+static int is_byte_reg(u32 reg)
+{
+	/*
+	 * These TPM registers are 8 bits wide and as such require byte access
+	 * on writes and truncated value on reads.
+	 */
+	return ((reg == TIS_REG_ACCESS)	||
+		(reg == TIS_REG_INT_VECTOR) ||
+		(reg == TIS_REG_DATA_FIFO));
+}
+
+/* TPM access functions are carved out to make tracing easier. */
+static u32 tpm_read(int locality, u32 reg)
+{
+	u32 value;
+	/*
+	 * Data FIFO register must be read and written in byte access mode,
+	 * otherwise the FIFO values are returned 4 bytes at a time.
+	 */
+	if (is_byte_reg(reg))
+		value = readb(TIS_REG(locality, reg));
+	else
+		value = readl(TIS_REG(locality, reg));
+
+	TPM_DEBUG("Read reg 0x%x returns 0x%x\n", reg, value);
+	return value;
+}
+
+static void tpm_write(u32 value, int locality,  u32 reg)
+{
+	TPM_DEBUG("Write reg 0x%x with 0x%x\n", reg, value);
+
+	if (is_byte_reg(reg))
+		writeb(value & 0xff, TIS_REG(locality, reg));
+	else
+		writel(value, TIS_REG(locality, reg));
+}
+
+/*
+ * tis_wait_reg()
+ *
+ * Wait for at least a second for a register to change its state to match the
+ * expected state. Normally the transition happens within microseconds.
+ *
+ * @reg - the TPM register offset
+ * @locality - locality
+ * @mask - bitmask for the bitfield(s) to watch
+ * @expected - value the field(s) are supposed to be set to
+ *
+ * Returns the register contents in case the expected value was found in the
+ * appropriate register bits, or TPM_TIMEOUT_ERR on timeout.
+ */
+static u32 tis_wait_reg(u8 reg, u8 locality, u8 mask, u8 expected)
+{
+	u32 time_us = MAX_DELAY_US;
+	while (time_us > 0) {
+		u32 value = tpm_read(locality, reg);
+		if ((value & mask) == expected)
+			return value;
+		udelay(1); /* 1 us */
+		time_us--;
+	}
+	return TPM_TIMEOUT_ERR;
+}
+
+/*
+ * Probe the TPM device and try determining its manufacturer/device name.
+ *
+ * Returns 0 on success (the device is found or was found during an earlier
+ * invocation) or TPM_DRIVER_ERR if the device is not found.
+ */
+static u32 tis_probe(void)
+{
+	u32 didvid = tpm_read(0, TIS_REG_DID_VID);
+	int i;
+	const char *device_name = "unknown";
+	const char *vendor_name = device_name;
+	u16 vid, did;
+
+	if (vendor_dev_id)
+		return 0;  /* Already probed. */
+
+	if (!didvid || (didvid == 0xffffffff)) {
+		printf("%s: No TPM device found\n", __FUNCTION__);
+		return TPM_DRIVER_ERR;
+	}
+
+	vendor_dev_id = didvid;
+
+	vid = didvid & 0xffff;
+	did = (didvid >> 16) & 0xffff;
+	for (i = 0; i < ARRAY_SIZE(vendor_names); i++) {
+		int j = 0;
+		u16 known_did;
+		if (vid == vendor_names[i].vendor_id) {
+			vendor_name = vendor_names[i].vendor_name;
+		}
+		while ((known_did = vendor_names[i].dev_names[j].dev_id) != 0) {
+			if (known_did == did) {
+				device_name =
+					vendor_names[i].dev_names[j].dev_name;
+				break;
+			}
+			j++;
+		}
+		break;
+	}
+	/* this will have to be converted into debug printout */
+	TPM_DEBUG("Found TPM %s by %s\n", device_name, vendor_name);
+	return 0;
+}
+
+/*
+ * tis_senddata()
+ *
+ * send the passed in data to the TPM device.
+ *
+ * @data - address of the data to send, byte by byte
+ * @len - length of the data to send
+ *
+ * Returns 0 on success, TPM_DRIVER_ERR on error (in case the device does
+ * not accept the entire command).
+ */
+static u32 tis_senddata(const u8 * const data, u32 len)
+{
+	u32 offset = 0;
+	u16 burst = 0;
+	u32 max_cycles = 0;
+	u8 locality = 0;
+	u32 value;
+
+	value = tis_wait_reg(TIS_REG_STS, locality, TIS_STS_COMMAND_READY,
+			     TIS_STS_COMMAND_READY);
+	if (value == TPM_TIMEOUT_ERR) {
+		printf("%s:%d - failed to get 'command_ready' status\n",
+		       __FILE__, __LINE__);
+		return TPM_DRIVER_ERR;
+	}
+	burst = BURST_COUNT(value);
+
+	while (1) {
+		unsigned count;
+
+		/* Wait till the device is ready to accept more data. */
+		while (!burst) {
+			if (max_cycles++ == MAX_DELAY_US) {
+				printf("%s:%d failed to feed %d bytes of %d\n",
+				       __FILE__, __LINE__, len - offset, len);
+				return TPM_DRIVER_ERR;
+			}
+			udelay(1);
+			burst = BURST_COUNT(tpm_read(locality, TIS_REG_STS));
+		}
+
+		max_cycles = 0;
+
+		/*
+		 * Calculate number of bytes the TPM is ready to accept in one
+		 * shot.
+		 *
+		 * We want to send the last byte outside of the loop (hence
+		 * the -1 below) to make sure that the 'expected' status bit
+		 * changes to zero exactly after the last byte is fed into the
+		 * FIFO.
+		 */
+		count = min(burst, len - offset - 1);
+		while (count--)
+			tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO);
+
+		value = tis_wait_reg(TIS_REG_STS, locality,
+				     TIS_STS_VALID, TIS_STS_VALID);
+
+		if ((value == TPM_TIMEOUT_ERR) || !(value & TIS_STS_EXPECT)) {
+			printf("%s:%d TPM command feed overflow\n",
+			       __FILE__, __LINE__);
+			return TPM_DRIVER_ERR;
+		}
+
+		burst = BURST_COUNT(value);
+		if ((offset == (len - 1)) && burst)
+			/*
+			 * We need to be able to send the last byte to the
+			 * device, so burst size must be nonzero before we
+			 * break out.
+			 */
+			break;
+	}
+
+	/* Send the last byte. */
+	tpm_write(data[offset++], locality, TIS_REG_DATA_FIFO);
+
+	/*
+	 * Verify that TPM does not expect any more data as part of this
+	 * command.
+	 */
+	value = tis_wait_reg(TIS_REG_STS, locality,
+			     TIS_STS_VALID, TIS_STS_VALID);
+	if ((value == TPM_TIMEOUT_ERR) || (value & TIS_STS_EXPECT)) {
+		printf("%s:%d unexpected TPM status 0x%x\n",
+		       __FILE__, __LINE__, value);
+		return TPM_DRIVER_ERR;
+	}
+
+	/* OK, sitting pretty, let's start the command execution. */
+	tpm_write(TIS_STS_TPM_GO, locality, TIS_REG_STS);
+
+	return 0;
+}
+
+/*
+ * tis_readresponse()
+ *
+ * read the TPM device response after a command was issued.
+ *
+ * @buffer - address where to read the response, byte by byte.
+ * @len - pointer to the size of buffer
+ *
+ * On success stores the number of received bytes to len and returns 0. On
+ * errors (misformatted TPM data or synchronization problems) returns
+ * TPM_DRIVER_ERR.
+ */
+static u32 tis_readresponse(u8 *buffer, size_t *len)
+{
+	u16 burst_count;
+	u32 status;
+	u32 offset = 0;
+	u8 locality = 0;
+	const u32 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID;
+	u32 expected_count = *len;
+	int max_cycles = 0;
+
+	/* Wait for the TPM to process the command */
+	status = tis_wait_reg(TIS_REG_STS, locality, has_data, has_data);
+	if (status == TPM_TIMEOUT_ERR) {
+		printf("%s:%d failed processing command\n",
+		       __FILE__, __LINE__);
+		return TPM_DRIVER_ERR;
+	}
+
+	do {
+		while ((burst_count = BURST_COUNT(status)) == 0) {
+			if (max_cycles++ == MAX_DELAY_US) {
+				printf("%s:%d TPM stuck on read\n",
+				       __FILE__, __LINE__);
+				return TPM_DRIVER_ERR;
+			}
+			udelay(1);
+			status = tpm_read(locality, TIS_REG_STS);
+		}
+
+		max_cycles = 0;
+
+		while (burst_count-- && (offset < expected_count)) {
+			buffer[offset++] = (u8) tpm_read(locality,
+							 TIS_REG_DATA_FIFO);
+			if (offset == 6) {
+				/*
+				 * We got the first six bytes of the reply,
+				 * let's figure out how many bytes to expect
+				 * total - it is stored as a 4 byte number in
+				 * network order, starting with offset 2 into
+				 * the body of the reply.
+				 */
+				u32 real_length;
+				memcpy(&real_length,
+				       buffer + 2,
+				       sizeof(real_length));
+				expected_count = be32_to_cpu(real_length);
+
+				if ((expected_count < offset) ||
+				    (expected_count > *len)) {
+					printf("%s:%d bad response size %d\n",
+					       __FILE__, __LINE__,
+					       expected_count);
+					return TPM_DRIVER_ERR;
+				}
+			}
+		}
+
+		/* Wait for the next portion */
+		status = tis_wait_reg(TIS_REG_STS, locality,
+				      TIS_STS_VALID, TIS_STS_VALID);
+		if (status == TPM_TIMEOUT_ERR) {
+			printf("%s:%d failed to read response\n",
+			       __FILE__, __LINE__);
+			return TPM_DRIVER_ERR;
+		}
+
+		if (offset == expected_count)
+			break;	/* We got all we need */
+
+	} while ((status & has_data) == has_data);
+
+	/*
+	 * Make sure we indeed read all there was. The TIS_STS_VALID bit is
+	 * known to be set.
+	 */
+	if (status & TIS_STS_DATA_AVAILABLE) {
+		printf("%s:%d wrong receive status %x\n",
+		       __FILE__, __LINE__, status);
+		return TPM_DRIVER_ERR;
+	}
+
+	/* Tell the TPM that we are done. */
+	tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS);
+
+	*len = offset;
+	return 0;
+}
+
+/*
+ * tis_init()
+ *
+ * Initialize the TPM device. Returns 0 on success or TPM_DRIVER_ERR on
+ * failure (in case device probing did not succeed).
+ */
+int tis_init(void)
+{
+	if (tis_probe())
+		return TPM_DRIVER_ERR;
+	return 0;
+}
+
+/*
+ * tis_open()
+ *
+ * Requests access to locality 0 for the caller. After all commands have been
+ * completed the caller is supposed to call tis_close().
+ *
+ * Returns 0 on success, TPM_DRIVER_ERR on failure.
+ */
+int tis_open(void)
+{
+	u8 locality = 0; /* we use locality zero for everything */
+
+	if (tis_close())
+		return TPM_DRIVER_ERR;
+
+	/* now request access to locality */
+	tpm_write(TIS_ACCESS_REQUEST_USE, locality, TIS_REG_ACCESS);
+
+	/* did we get a lock? */
+	if (tis_wait_reg(TIS_REG_ACCESS, locality,
+			 TIS_ACCESS_ACTIVE_LOCALITY,
+			 TIS_ACCESS_ACTIVE_LOCALITY) == TPM_TIMEOUT_ERR) {
+		printf("%s:%d - failed to lock locality %d\n",
+		       __FILE__, __LINE__, locality);
+		return TPM_DRIVER_ERR;
+	}
+
+	tpm_write(TIS_STS_COMMAND_READY, locality, TIS_REG_STS);
+
+	return 0;
+}
+
+/*
+ * tis_close()
+ *
+ * terminate the currect session with the TPM by releasing the locked
+ * locality. Returns 0 on success of TPM_DRIVER_ERR on failure (in case lock
+ * removal did not succeed).
+ */
+int tis_close(void)
+{
+	u8 locality = 0;
+	if (tpm_read(locality, TIS_REG_ACCESS) &
+	    TIS_ACCESS_ACTIVE_LOCALITY) {
+		tpm_write(TIS_ACCESS_ACTIVE_LOCALITY, locality, TIS_REG_ACCESS);
+
+		if (tis_wait_reg(TIS_REG_ACCESS, locality,
+				 TIS_ACCESS_ACTIVE_LOCALITY, 0) ==
+		    TPM_TIMEOUT_ERR) {
+			printf("%s:%d - failed to release locality %d\n",
+			       __FILE__, __LINE__, locality);
+			return TPM_DRIVER_ERR;
+		}
+	}
+	return 0;
+}
+
+/*
+ * tis_sendrecv()
+ *
+ * Send the requested data to the TPM and then try to get its response
+ *
+ * @sendbuf - buffer of the data to send
+ * @send_size size of the data to send
+ * @recvbuf - memory to save the response to
+ * @recv_len - pointer to the size of the response buffer
+ *
+ * Returns 0 on success (and places the number of response bytes at recv_len)
+ * or TPM_DRIVER_ERR on failure.
+ */
+int tis_sendrecv(const uint8_t *sendbuf, size_t send_size,
+		 uint8_t *recvbuf, size_t *recv_len)
+{
+	if (tis_senddata(sendbuf, send_size)) {
+		printf("%s:%d failed sending data to TPM\n",
+		       __FILE__, __LINE__);
+		return TPM_DRIVER_ERR;
+	}
+
+	return tis_readresponse(recvbuf, recv_len);
+}