@@ -145,6 +145,15 @@ config TPM2_TIS_SPI
to the device using the standard TPM Interface Specification (TIS)
protocol.
+config TPM2_TIS_I2C
+ bool "Enable support for TPMv2.x I2C chips"
+ depends on TPM_V2 && DM_I2C
+ help
+ This driver supports TPMv2.x devices connected on the I2C bus.
+ The usual TPM operations and the 'tpm' command can be used to talk
+ to the device using the standard TPM Interface Specification (TIS)
+ protocol.
+
endif # TPM_V2
endmenu
@@ -12,3 +12,4 @@ obj-$(CONFIG_TPM_ST33ZP24_SPI) += tpm_tis_st33zp24_spi.o
obj-$(CONFIG_TPM2_TIS_SANDBOX) += tpm2_tis_sandbox.o
obj-$(CONFIG_TPM2_TIS_SPI) += tpm2_tis_spi.o
+obj-$(CONFIG_TPM2_TIS_I2C) += tpm2_tis_core.o tpm2_tis_i2c.o
new file mode 100644
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2022 IBM Corp.
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include <log.h>
+#include <tpm-v2.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <linux/unaligned/be_byteshift.h>
+#include <asm-generic/gpio.h>
+
+#include "tpm_tis.h"
+#include "tpm_internal.h"
+
+struct tpm_tis_chip_data {
+ unsigned int pcr_count;
+ unsigned int pcr_select_min;
+};
+
+static uint tpm_tis_i2c_address_to_register(u32 addr)
+{
+ addr &= 0xFFF;
+
+ /*
+ * Adapt register addresses that have changed compared to older TIS
+ * version.
+ */
+ switch (addr) {
+ case TPM_ACCESS(0):
+ return 0x04;
+ case TPM_DID_VID(0):
+ return 0x48;
+ case TPM_RID(0):
+ return 0x4C;
+ default:
+ return addr;
+ }
+}
+
+static int tpm_tis_i2c_read(struct udevice *dev, u32 addr, u16 len, u8 *in)
+{
+ int rc;
+ int count = 0;
+ uint reg = tpm_tis_i2c_address_to_register(addr);
+
+ do {
+ rc = dm_i2c_read(dev, reg, in, len);
+ udelay(SLEEP_DURATION_US);
+ } while (rc && count++ < MAX_COUNT);
+
+ return rc;
+}
+
+static int tpm_tis_i2c_write(struct udevice *dev, u32 addr, u16 len,
+ const u8 *out)
+{
+ int rc;
+ int count = 0;
+ uint reg = tpm_tis_i2c_address_to_register(addr);
+
+ do {
+ rc = dm_i2c_write(dev, reg, out, len);
+ udelay(SLEEP_DURATION_US);
+ } while (rc && count++ < MAX_COUNT);
+
+ return rc;
+}
+
+static int tpm_tis_i2c_read32(struct udevice *dev, u32 addr, u32 *result)
+{
+ __le32 result_le;
+ int rc;
+
+ rc = tpm_tis_i2c_read(dev, addr, sizeof(u32), (u8 *)&result_le);
+ if (!rc)
+ *result = le32_to_cpu(result_le);
+
+ return rc;
+}
+
+static int tpm_tis_i2c_write32(struct udevice *dev, u32 addr, u32 value)
+{
+ __le32 value_le = cpu_to_le32(value);
+
+ return tpm_tis_i2c_write(dev, addr, sizeof(value), (u8 *)&value_le);
+}
+
+static struct tpm_tis_phy_ops phy_ops = {
+ .read_bytes = tpm_tis_i2c_read,
+ .write_bytes = tpm_tis_i2c_write,
+ .read32 = tpm_tis_i2c_read32,
+ .write32 = tpm_tis_i2c_write32,
+};
+
+static int tpm_tis_i2c_probe(struct udevice *udev)
+{
+ struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
+ struct tpm_chip_priv *priv = dev_get_uclass_priv(udev);
+ int rc;
+ u8 loc = 0;
+
+ tpm_tis_ops_register(udev, &phy_ops);
+
+ /*
+ * Force locality 0. The core driver doesn't actually write the
+ * locality register and instead just reads/writes various access
+ * bits of the selected locality.
+ */
+ rc = dm_i2c_write(udev, 0, &loc, 1);
+ if (rc)
+ return rc;
+
+ rc = tpm_tis_init(udev);
+ if (rc)
+ return rc;
+
+ priv->pcr_count = drv_data->pcr_count;
+ priv->pcr_select_min = drv_data->pcr_select_min;
+ priv->version = TPM_V2;
+
+ return 0;
+}
+
+static int tpm_tis_i2c_remove(struct udevice *udev)
+{
+ return tpm_tis_cleanup(udev);
+}
+
+static const struct tpm_ops tpm_tis_i2c_ops = {
+ .open = tpm_tis_open,
+ .close = tpm_tis_close,
+ .get_desc = tpm_tis_get_desc,
+ .send = tpm_tis_send,
+ .recv = tpm_tis_recv,
+ .cleanup = tpm_tis_cleanup,
+};
+
+static const struct tpm_tis_chip_data tpm_tis_std_chip_data = {
+ .pcr_count = 24,
+ .pcr_select_min = 3,
+};
+
+static const struct udevice_id tpm_tis_i2c_ids[] = {
+ {
+ .compatible = "nuvoton,npct75x",
+ .data = (ulong)&tpm_tis_std_chip_data,
+ },
+ {
+ .compatible = "tcg,tpm-tis-i2c",
+ .data = (ulong)&tpm_tis_std_chip_data,
+ },
+ { }
+};
+
+U_BOOT_DRIVER(tpm_tis_i2c) = {
+ .name = "tpm_tis_i2c",
+ .id = UCLASS_TPM,
+ .of_match = tpm_tis_i2c_ids,
+ .ops = &tpm_tis_i2c_ops,
+ .probe = tpm_tis_i2c_probe,
+ .remove = tpm_tis_i2c_remove,
+ .priv_auto_alloc_size = sizeof(struct tpm_chip),
+};
Add the tpm2_tis_i2c driver that should support any TPMv2 compliant I2C chips, such as the NPCT75X chip. Signed-off-by: Eddie James <eajames@linux.ibm.com> --- drivers/tpm/Kconfig | 9 ++ drivers/tpm/Makefile | 1 + drivers/tpm/tpm2_tis_i2c.c | 171 +++++++++++++++++++++++++++++++++++++ 3 files changed, 181 insertions(+) create mode 100644 drivers/tpm/tpm2_tis_i2c.c