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Diffstat (limited to 'roms/u-boot/drivers/tpm/tpm_tis_lpc.c')
-rw-r--r--roms/u-boot/drivers/tpm/tpm_tis_lpc.c479
1 files changed, 479 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/tpm/tpm_tis_lpc.c b/roms/u-boot/drivers/tpm/tpm_tis_lpc.c
new file mode 100644
index 000000000..003c0d881
--- /dev/null
+++ b/roms/u-boot/drivers/tpm/tpm_tis_lpc.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ */
+
+/*
+ * The code in this file is based on the article "Writing a TPM Device Driver"
+ * published on http://ptgmedia.pearsoncmg.com.
+ *
+ * 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 <common.h>
+#include <dm.h>
+#include <log.h>
+#include <mapmem.h>
+#include <tpm-v1.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+
+#define PREFIX "lpc_tpm: "
+
+enum i2c_chip_type {
+ SLB9635,
+ AT97SC3204,
+};
+
+static const char * const chip_name[] = {
+ [SLB9635] = "Infineon SLB9635 TT 1.2",
+ [AT97SC3204] = "Atmel AT97SC3204",
+};
+
+static const u32 chip_didvid[] = {
+ [SLB9635] = 0xb15d1,
+ [AT97SC3204] = 0x32041114,
+};
+
+struct tpm_locality {
+ u32 access;
+ u8 padding0[4];
+ u32 int_enable;
+ u8 vector;
+ u8 padding1[3];
+ u32 int_status;
+ u32 int_capability;
+ u32 tpm_status;
+ u8 padding2[8];
+ u8 data;
+ u8 padding3[3803];
+ u32 did_vid;
+ u8 rid;
+ u8 padding4[251];
+};
+
+struct tpm_tis_lpc_priv {
+ struct tpm_locality *regs;
+};
+
+/*
+ * This pointer refers to the TPM chip, 5 of its localities are mapped as an
+ * array.
+ */
+#define TPM_TOTAL_LOCALITIES 5
+
+/* 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)
+
+ /* 1 second is plenty for anything TPM does. */
+#define MAX_DELAY_US (1000 * 1000)
+
+/* Retrieve burst count value out of the status register contents. */
+static u16 burst_count(u32 status)
+{
+ return (status >> TIS_STS_BURST_COUNT_SHIFT) &
+ TIS_STS_BURST_COUNT_MASK;
+}
+
+/* TPM access wrappers to support tracing */
+static u8 tpm_read_byte(struct tpm_tis_lpc_priv *priv, const u8 *ptr)
+{
+ u8 ret = readb(ptr);
+ debug(PREFIX "Read reg 0x%4.4x returns 0x%2.2x\n",
+ (u32)(uintptr_t)ptr - (u32)(uintptr_t)priv->regs, ret);
+ return ret;
+}
+
+static u32 tpm_read_word(struct tpm_tis_lpc_priv *priv, const u32 *ptr)
+{
+ u32 ret = readl(ptr);
+ debug(PREFIX "Read reg 0x%4.4x returns 0x%8.8x\n",
+ (u32)(uintptr_t)ptr - (u32)(uintptr_t)priv->regs, ret);
+ return ret;
+}
+
+static void tpm_write_byte(struct tpm_tis_lpc_priv *priv, u8 value, u8 *ptr)
+{
+ debug(PREFIX "Write reg 0x%4.4x with 0x%2.2x\n",
+ (u32)(uintptr_t)ptr - (u32)(uintptr_t)priv->regs, value);
+ writeb(value, ptr);
+}
+
+static void tpm_write_word(struct tpm_tis_lpc_priv *priv, u32 value,
+ u32 *ptr)
+{
+ debug(PREFIX "Write reg 0x%4.4x with 0x%8.8x\n",
+ (u32)(uintptr_t)ptr - (u32)(uintptr_t)priv->regs, value);
+ writel(value, ptr);
+}
+
+/*
+ * 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 - pointer to the TPM register
+ * @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 -ETIMEDOUT on timeout.
+ */
+static int tis_wait_reg(struct tpm_tis_lpc_priv *priv, u32 *reg, u8 mask,
+ u8 expected)
+{
+ u32 time_us = MAX_DELAY_US;
+
+ while (time_us > 0) {
+ u32 value = tpm_read_word(priv, reg);
+ if ((value & mask) == expected)
+ return value;
+ udelay(1); /* 1 us */
+ time_us--;
+ }
+
+ return -ETIMEDOUT;
+}
+
+/*
+ * Probe the TPM device and try determining its manufacturer/device name.
+ *
+ * Returns 0 on success, -ve on error
+ */
+static int tpm_tis_lpc_probe(struct udevice *dev)
+{
+ struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+ fdt_addr_t addr;
+ u32 didvid;
+ ulong chip_type = dev_get_driver_data(dev);
+
+ addr = dev_read_addr(dev);
+ if (addr == FDT_ADDR_T_NONE)
+ return -EINVAL;
+ priv->regs = map_sysmem(addr, 0);
+ didvid = tpm_read_word(priv, &priv->regs[0].did_vid);
+
+ if (didvid != chip_didvid[chip_type]) {
+ u32 vid, did;
+ vid = didvid & 0xffff;
+ did = (didvid >> 16) & 0xffff;
+ debug("Invalid vendor/device ID %04x/%04x\n", vid, did);
+ return -ENODEV;
+ }
+
+ debug("Found TPM: %s\n", chip_name[chip_type]);
+
+ 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, -ve on error (in case the device does not accept
+ * the entire command).
+ */
+static int tis_senddata(struct udevice *dev, const u8 *data, size_t len)
+{
+ struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+ struct tpm_locality *regs = priv->regs;
+ u32 offset = 0;
+ u16 burst = 0;
+ u32 max_cycles = 0;
+ u8 locality = 0;
+ u32 value;
+
+ value = tis_wait_reg(priv, &regs[locality].tpm_status,
+ TIS_STS_COMMAND_READY, TIS_STS_COMMAND_READY);
+ if (value == -ETIMEDOUT) {
+ printf("%s:%d - failed to get 'command_ready' status\n",
+ __FILE__, __LINE__);
+ return value;
+ }
+ 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 %zd bytes of %zd\n",
+ __FILE__, __LINE__, len - offset, len);
+ return -ETIMEDOUT;
+ }
+ udelay(1);
+ burst = burst_count(tpm_read_word(priv,
+ &regs[locality].tpm_status));
+ }
+
+ 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((size_t)burst, len - offset - 1);
+ while (count--)
+ tpm_write_byte(priv, data[offset++],
+ &regs[locality].data);
+
+ value = tis_wait_reg(priv, &regs[locality].tpm_status,
+ TIS_STS_VALID, TIS_STS_VALID);
+
+ if ((value == -ETIMEDOUT) || !(value & TIS_STS_EXPECT)) {
+ printf("%s:%d TPM command feed overflow\n",
+ __FILE__, __LINE__);
+ return value == -ETIMEDOUT ? value : -EIO;
+ }
+
+ 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_byte(priv, data[offset++], &regs[locality].data);
+ /*
+ * Verify that TPM does not expect any more data as part of this
+ * command.
+ */
+ value = tis_wait_reg(priv, &regs[locality].tpm_status,
+ TIS_STS_VALID, TIS_STS_VALID);
+ if ((value == -ETIMEDOUT) || (value & TIS_STS_EXPECT)) {
+ printf("%s:%d unexpected TPM status 0x%x\n",
+ __FILE__, __LINE__, value);
+ return value == -ETIMEDOUT ? value : -EIO;
+ }
+
+ /* OK, sitting pretty, let's start the command execution. */
+ tpm_write_word(priv, TIS_STS_TPM_GO, &regs[locality].tpm_status);
+ 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
+ * -ve value.
+ */
+static int tis_readresponse(struct udevice *dev, u8 *buffer, size_t len)
+{
+ struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+ struct tpm_locality *regs = priv->regs;
+ u16 burst;
+ u32 value;
+ 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. */
+ value = tis_wait_reg(priv, &regs[locality].tpm_status,
+ has_data, has_data);
+ if (value == -ETIMEDOUT) {
+ printf("%s:%d failed processing command\n",
+ __FILE__, __LINE__);
+ return value;
+ }
+
+ do {
+ while ((burst = burst_count(value)) == 0) {
+ if (max_cycles++ == MAX_DELAY_US) {
+ printf("%s:%d TPM stuck on read\n",
+ __FILE__, __LINE__);
+ return -EIO;
+ }
+ udelay(1);
+ value = tpm_read_word(priv, &regs[locality].tpm_status);
+ }
+
+ max_cycles = 0;
+
+ while (burst-- && (offset < expected_count)) {
+ buffer[offset++] = tpm_read_byte(priv,
+ &regs[locality].data);
+
+ 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 -ENOSPC;
+ }
+ }
+ }
+
+ /* Wait for the next portion. */
+ value = tis_wait_reg(priv, &regs[locality].tpm_status,
+ TIS_STS_VALID, TIS_STS_VALID);
+ if (value == -ETIMEDOUT) {
+ printf("%s:%d failed to read response\n",
+ __FILE__, __LINE__);
+ return value;
+ }
+
+ if (offset == expected_count)
+ break; /* We got all we needed. */
+
+ } while ((value & has_data) == has_data);
+
+ /*
+ * Make sure we indeed read all there was. The TIS_STS_VALID bit is
+ * known to be set.
+ */
+ if (value & TIS_STS_DATA_AVAILABLE) {
+ printf("%s:%d wrong receive status %x\n",
+ __FILE__, __LINE__, value);
+ return -EBADMSG;
+ }
+
+ /* Tell the TPM that we are done. */
+ tpm_write_word(priv, TIS_STS_COMMAND_READY,
+ &regs[locality].tpm_status);
+
+ return offset;
+}
+
+static int tpm_tis_lpc_close(struct udevice *dev)
+{
+ struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+ struct tpm_locality *regs = priv->regs;
+ u8 locality = 0;
+
+ if (tpm_read_word(priv, &regs[locality].access) &
+ TIS_ACCESS_ACTIVE_LOCALITY) {
+ tpm_write_word(priv, TIS_ACCESS_ACTIVE_LOCALITY,
+ &regs[locality].access);
+
+ if (tis_wait_reg(priv, &regs[locality].access,
+ TIS_ACCESS_ACTIVE_LOCALITY, 0) == -ETIMEDOUT) {
+ printf("%s:%d - failed to release locality %d\n",
+ __FILE__, __LINE__, locality);
+ return -ETIMEDOUT;
+ }
+ }
+ return 0;
+}
+
+static int tpm_tis_lpc_open(struct udevice *dev)
+{
+ struct tpm_tis_lpc_priv *priv = dev_get_priv(dev);
+ struct tpm_locality *regs = priv->regs;
+ u8 locality = 0; /* we use locality zero for everything. */
+ int ret;
+
+ ret = tpm_tis_lpc_close(dev);
+ if (ret) {
+ printf("%s: Failed to close TPM\n", __func__);
+ return ret;
+ }
+
+ /* now request access to locality. */
+ tpm_write_word(priv, TIS_ACCESS_REQUEST_USE, &regs[locality].access);
+
+ /* did we get a lock? */
+ ret = tis_wait_reg(priv, &regs[locality].access,
+ TIS_ACCESS_ACTIVE_LOCALITY,
+ TIS_ACCESS_ACTIVE_LOCALITY);
+ if (ret == -ETIMEDOUT) {
+ printf("%s:%d - failed to lock locality %d\n",
+ __FILE__, __LINE__, locality);
+ return ret;
+ }
+
+ tpm_write_word(priv, TIS_STS_COMMAND_READY,
+ &regs[locality].tpm_status);
+
+ return 0;
+}
+
+static int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
+{
+ ulong chip_type = dev_get_driver_data(dev);
+
+ if (size < 50)
+ return -ENOSPC;
+
+ return snprintf(buf, size, "1.2 TPM (%s)",
+ chip_name[chip_type]);
+}
+
+
+static const struct tpm_ops tpm_tis_lpc_ops = {
+ .open = tpm_tis_lpc_open,
+ .close = tpm_tis_lpc_close,
+ .get_desc = tpm_tis_get_desc,
+ .send = tis_senddata,
+ .recv = tis_readresponse,
+};
+
+static const struct udevice_id tpm_tis_lpc_ids[] = {
+ { .compatible = "infineon,slb9635lpc", .data = SLB9635 },
+ { .compatible = "atmel,at97sc3204", .data = AT97SC3204 },
+ { }
+};
+
+U_BOOT_DRIVER(tpm_tis_lpc) = {
+ .name = "tpm_tis_lpc",
+ .id = UCLASS_TPM,
+ .of_match = tpm_tis_lpc_ids,
+ .ops = &tpm_tis_lpc_ops,
+ .probe = tpm_tis_lpc_probe,
+ .priv_auto = sizeof(struct tpm_tis_lpc_priv),
+};