diff --git a/Documentation/devicetree/bindings/security/tpm/tpm_tis_spi.txt b/Documentation/devicetree/bindings/security/tpm/tpm_tis_spi.txt new file mode 100644 index 000000000000..85741cd468cc --- /dev/null +++ b/Documentation/devicetree/bindings/security/tpm/tpm_tis_spi.txt @@ -0,0 +1,24 @@ +Required properties: +- compatible: should be one of the following + "st,st33htpm-spi" + "infineon,slb9670" + "tcg,tpm_tis-spi" +- spi-max-frequency: Maximum SPI frequency (depends on TPMs). + +Optional SoC Specific Properties: +- pinctrl-names: Contains only one value - "default". +- pintctrl-0: Specifies the pin control groups used for this controller. + +Example (for ARM-based BeagleBoard xM with TPM_TIS on SPI4): + +&mcspi4 { + + status = "okay"; + + tpm_tis@0 { + + compatible = "tcg,tpm_tis-spi"; + + spi-max-frequency = <10000000>; + }; +}; diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig index 241ff4cc52a8..9faa0b1e7766 100644 --- a/drivers/char/tpm/Kconfig +++ b/drivers/char/tpm/Kconfig @@ -41,6 +41,18 @@ config TCG_TIS within Linux. To compile this driver as a module, choose M here; the module will be called tpm_tis. +config TCG_TIS_SPI + tristate "TPM Interface Specification 1.3 Interface / TPM 2.0 FIFO Interface - (SPI)" + depends on SPI + select TCG_TIS_CORE + ---help--- + If you have a TPM security chip which is connected to a regular, + non-tcg SPI master (i.e. most embedded platforms) that is compliant with the + TCG TIS 1.3 TPM specification (TPM1.2) or the TCG PTP FIFO + specification (TPM2.0) say Yes and it will be accessible from + within Linux. To compile this driver as a module, choose M here; + the module will be called tpm_tis_spi. + config TCG_TIS_I2C_ATMEL tristate "TPM Interface Specification 1.2 Interface (I2C - Atmel)" depends on I2C diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index 662221f83018..a385fb8c17de 100644 --- a/drivers/char/tpm/Makefile +++ b/drivers/char/tpm/Makefile @@ -14,6 +14,7 @@ endif endif obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o obj-$(CONFIG_TCG_TIS) += tpm_tis.o +obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o obj-$(CONFIG_TCG_TIS_I2C_ATMEL) += tpm_i2c_atmel.o obj-$(CONFIG_TCG_TIS_I2C_INFINEON) += tpm_i2c_infineon.o obj-$(CONFIG_TCG_TIS_I2C_NUVOTON) += tpm_i2c_nuvoton.o diff --git a/drivers/char/tpm/tpm_tis_spi.c b/drivers/char/tpm/tpm_tis_spi.c new file mode 100644 index 000000000000..dbaad9c681e3 --- /dev/null +++ b/drivers/char/tpm/tpm_tis_spi.c @@ -0,0 +1,272 @@ +/* + * Copyright (C) 2015 Infineon Technologies AG + * Copyright (C) 2016 STMicroelectronics SAS + * + * Authors: + * Peter Huewe + * Christophe Ricard + * + * Maintained by: + * + * Device driver for TCG/TCPA TPM (trusted platform module). + * Specifications at www.trustedcomputinggroup.org + * + * This device driver implements the TPM interface as defined in + * the TCG TPM Interface Spec version 1.3, revision 27 via _raw/native + * SPI access_. + * + * It is based on the original tpm_tis device driver from Leendert van + * Dorn and Kyleen Hall and Jarko Sakkinnen. + * + * 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. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include "tpm.h" +#include "tpm_tis_core.h" + +#define MAX_SPI_FRAMESIZE 64 + +struct tpm_tis_spi_phy { + struct tpm_tis_data priv; + struct spi_device *spi_device; + + u8 tx_buf[MAX_SPI_FRAMESIZE + 4]; + u8 rx_buf[MAX_SPI_FRAMESIZE + 4]; +}; + +static inline struct tpm_tis_spi_phy *to_tpm_tis_spi_phy(struct tpm_tis_data *data) +{ + return container_of(data, struct tpm_tis_spi_phy, priv); +} + +static int tpm_tis_spi_read_bytes(struct tpm_tis_data *data, u32 addr, + u16 len, u8 *result) +{ + struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data); + int ret, i; + struct spi_message m; + struct spi_transfer spi_xfer = { + .tx_buf = phy->tx_buf, + .rx_buf = phy->rx_buf, + .len = 4, + }; + + if (len > MAX_SPI_FRAMESIZE) + return -ENOMEM; + + phy->tx_buf[0] = 0x80 | (len - 1); + phy->tx_buf[1] = 0xd4; + phy->tx_buf[2] = (addr >> 8) & 0xFF; + phy->tx_buf[3] = addr & 0xFF; + + spi_xfer.cs_change = 1; + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + + spi_bus_lock(phy->spi_device->master); + ret = spi_sync_locked(phy->spi_device, &m); + if (ret < 0) + goto exit; + + memset(phy->tx_buf, 0, len); + + /* According to TCG PTP specification, if there is no TPM present at + * all, then the design has a weak pull-up on MISO. If a TPM is not + * present, a pull-up on MISO means that the SB controller sees a 1, + * and will latch in 0xFF on the read. + */ + for (i = 0; (phy->rx_buf[0] & 0x01) == 0 && i < TPM_RETRY; i++) { + spi_xfer.len = 1; + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + ret = spi_sync_locked(phy->spi_device, &m); + if (ret < 0) + goto exit; + } + + spi_xfer.cs_change = 0; + spi_xfer.len = len; + spi_xfer.rx_buf = result; + + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + ret = spi_sync_locked(phy->spi_device, &m); + +exit: + spi_bus_unlock(phy->spi_device->master); + return ret; +} + +static int tpm_tis_spi_write_bytes(struct tpm_tis_data *data, u32 addr, + u16 len, u8 *value) +{ + struct tpm_tis_spi_phy *phy = to_tpm_tis_spi_phy(data); + int ret, i; + struct spi_message m; + struct spi_transfer spi_xfer = { + .tx_buf = phy->tx_buf, + .rx_buf = phy->rx_buf, + .len = 4, + }; + + if (len > MAX_SPI_FRAMESIZE) + return -ENOMEM; + + phy->tx_buf[0] = len - 1; + phy->tx_buf[1] = 0xd4; + phy->tx_buf[2] = (addr >> 8) & 0xFF; + phy->tx_buf[3] = addr & 0xFF; + + spi_xfer.cs_change = 1; + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + + spi_bus_lock(phy->spi_device->master); + ret = spi_sync_locked(phy->spi_device, &m); + if (ret < 0) + goto exit; + + memset(phy->tx_buf, 0, len); + + /* According to TCG PTP specification, if there is no TPM present at + * all, then the design has a weak pull-up on MISO. If a TPM is not + * present, a pull-up on MISO means that the SB controller sees a 1, + * and will latch in 0xFF on the read. + */ + for (i = 0; (phy->rx_buf[0] & 0x01) == 0 && i < TPM_RETRY; i++) { + spi_xfer.len = 1; + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + ret = spi_sync_locked(phy->spi_device, &m); + if (ret < 0) + goto exit; + } + + spi_xfer.len = len; + spi_xfer.tx_buf = value; + spi_xfer.cs_change = 0; + spi_xfer.tx_buf = value; + spi_message_init(&m); + spi_message_add_tail(&spi_xfer, &m); + ret = spi_sync_locked(phy->spi_device, &m); + +exit: + spi_bus_unlock(phy->spi_device->master); + return ret; +} + +static int tpm_tis_spi_read16(struct tpm_tis_data *data, u32 addr, u16 *result) +{ + int rc; + + rc = data->phy_ops->read_bytes(data, addr, sizeof(u16), (u8 *)result); + if (!rc) + *result = le16_to_cpu(*result); + return rc; +} + +static int tpm_tis_spi_read32(struct tpm_tis_data *data, u32 addr, u32 *result) +{ + int rc; + + rc = data->phy_ops->read_bytes(data, addr, sizeof(u32), (u8 *)result); + if (!rc) + *result = le32_to_cpu(*result); + return rc; +} + +static int tpm_tis_spi_write32(struct tpm_tis_data *data, u32 addr, u32 value) +{ + value = cpu_to_le32(value); + return data->phy_ops->write_bytes(data, addr, sizeof(u32), + (u8 *)&value); +} + +static const struct tpm_tis_phy_ops tpm_spi_phy_ops = { + .read_bytes = tpm_tis_spi_read_bytes, + .write_bytes = tpm_tis_spi_write_bytes, + .read16 = tpm_tis_spi_read16, + .read32 = tpm_tis_spi_read32, + .write32 = tpm_tis_spi_write32, +}; + +static int tpm_tis_spi_probe(struct spi_device *dev) +{ + struct tpm_tis_spi_phy *phy; + + phy = devm_kzalloc(&dev->dev, sizeof(struct tpm_tis_spi_phy), + GFP_KERNEL); + if (!phy) + return -ENOMEM; + + phy->spi_device = dev; + + return tpm_tis_core_init(&dev->dev, &phy->priv, -1, &tpm_spi_phy_ops, + NULL); +} + +static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume); + +static int tpm_tis_spi_remove(struct spi_device *dev) +{ + struct tpm_chip *chip = spi_get_drvdata(dev); + + tpm_chip_unregister(chip); + tpm_tis_remove(chip); + return 0; +} + +static const struct spi_device_id tpm_tis_spi_id[] = { + {"tpm_tis_spi", 0}, + {} +}; +MODULE_DEVICE_TABLE(spi, tpm_tis_spi_id); + +static const struct of_device_id of_tis_spi_match[] = { + { .compatible = "st,st33htpm-spi", }, + { .compatible = "infineon,slb9670", }, + { .compatible = "tcg,tpm_tis-spi", }, + {} +}; +MODULE_DEVICE_TABLE(of, of_tis_spi_match); + +static const struct acpi_device_id acpi_tis_spi_match[] = { + {"SMO0768", 0}, + {} +}; +MODULE_DEVICE_TABLE(acpi, acpi_tis_spi_match); + +static struct spi_driver tpm_tis_spi_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "tpm_tis_spi", + .pm = &tpm_tis_pm, + .of_match_table = of_match_ptr(of_tis_spi_match), + .acpi_match_table = ACPI_PTR(acpi_tis_spi_match), + }, + .probe = tpm_tis_spi_probe, + .remove = tpm_tis_spi_remove, + .id_table = tpm_tis_spi_id, +}; +module_spi_driver(tpm_tis_spi_driver); + +MODULE_DESCRIPTION("TPM Driver for native SPI access"); +MODULE_LICENSE("GPL");