From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6B303C2D0EE for ; Tue, 31 Mar 2020 12:20:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3752B207FF for ; Tue, 31 Mar 2020 12:20:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730570AbgCaMU1 (ORCPT ); Tue, 31 Mar 2020 08:20:27 -0400 Received: from mga07.intel.com ([134.134.136.100]:47847 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730343AbgCaMU0 (ORCPT ); Tue, 31 Mar 2020 08:20:26 -0400 IronPort-SDR: jbxyutGQ45u1rUUuFwA7jPcJBcor6cz+76v6JZwDzjUE2JPtZb+A+pWxGwAQqrR1VEhZ23m74w b/noNcrvYNaQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Mar 2020 05:20:23 -0700 IronPort-SDR: AmZp5kKDQyRag9za5g+qVlOGgvZ2oJAjKP6s55ExrR+UaZjq2hFr37M+ytY/TqDZLK0jzFz/pu IJwwMHn4l3EA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,327,1580803200"; d="scan'208";a="249033366" Received: from tking1-mobl2.ger.corp.intel.com (HELO localhost) ([10.252.59.94]) by orsmga003.jf.intel.com with ESMTP; 31 Mar 2020 05:20:14 -0700 Date: Tue, 31 Mar 2020 15:20:13 +0300 From: Jarkko Sakkinen To: amirmizi6@gmail.com Cc: Eyal.Cohen@nuvoton.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, mark.rutland@arm.com, peterhuewe@gmx.de, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com Subject: Re: [PATCH v4 7/7] tpm: tpm_tis: add tpm_tis_i2c driver Message-ID: <20200331122013.GC9284@linux.intel.com> References: <20200331113207.107080-1-amirmizi6@gmail.com> <20200331113207.107080-8-amirmizi6@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200331113207.107080-8-amirmizi6@gmail.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 31, 2020 at 02:32:07PM +0300, amirmizi6@gmail.com wrote: > From: Amir Mizinski > > Implements the functionality needed to communicate with an I2C TPM > according to the TCG TPM I2C Interface Specification. > > Signed-off-by: Amir Mizinski > --- > drivers/char/tpm/Kconfig | 12 ++ > drivers/char/tpm/Makefile | 1 + > drivers/char/tpm/tpm_tis_i2c.c | 292 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 305 insertions(+) > create mode 100644 drivers/char/tpm/tpm_tis_i2c.c > > diff --git a/drivers/char/tpm/Kconfig b/drivers/char/tpm/Kconfig > index aacdeed..b482bbf 100644 > --- a/drivers/char/tpm/Kconfig > +++ b/drivers/char/tpm/Kconfig > @@ -74,6 +74,18 @@ config TCG_TIS_SPI_CR50 > If you have a H1 secure module running Cr50 firmware on SPI bus, > say Yes and it will be accessible from within Linux. > > +config TCG_TIS_I2C > + tristate "TPM I2C Interface Specification" > + depends on I2C > + depends on CRC_CCITT > + select TCG_TIS_CORE > + ---help--- > + If you have a TPM security chip which is connected to a regular > + I2C master (i.e. most embedded platforms) that is compliant with the > + TCG TPM I2C Interface Specification 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_i2c. > + > 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 9567e51..97999cf 100644 > --- a/drivers/char/tpm/Makefile > +++ b/drivers/char/tpm/Makefile > @@ -26,6 +26,7 @@ obj-$(CONFIG_TCG_TIS_SPI) += tpm_tis_spi.o > tpm_tis_spi-y := tpm_tis_spi_main.o > tpm_tis_spi-$(CONFIG_TCG_TIS_SPI_CR50) += tpm_tis_spi_cr50.o > > +obj-$(CONFIG_TCG_TIS_I2C) += tpm_tis_i2c.o > obj-$(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_i2c.c b/drivers/char/tpm/tpm_tis_i2c.c > new file mode 100644 > index 0000000..c10ec7e > --- /dev/null > +++ b/drivers/char/tpm/tpm_tis_i2c.c > @@ -0,0 +1,292 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2014-2019 Nuvoton Technology corporation > + * > + * TPM TIS I2C > + * > + * TPM TIS I2C Device Driver Interface for devices that implement the TPM I2C > + * Interface defined by TCG PC Client Platform TPM Profile (PTP) Specification > + * Revision 01.03 v22 at www.trustedcomputinggroup.org > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include "tpm.h" > +#include "tpm_tis_core.h" > + > +#define TPM_LOC_SEL 0x04 > +#define TPM_I2C_INTERFACE_CAPABILITY 0x30 > +#define TPM_I2C_DEVICE_ADDRESS 0x38 > +#define TPM_DATA_CSUM_ENABLE 0x40 > +#define TPM_DATA_CSUM 0x44 > +#define TPM_I2C_DID_VID 0x48 > +#define TPM_I2C_RID 0x4C > + > +//#define I2C_IS_TPM2 1 > + > +struct tpm_tis_i2c_phy { > + struct tpm_tis_data priv; > + struct i2c_client *i2c_client; > + bool data_csum; > + u8 *iobuf; > +}; > + > +static inline struct tpm_tis_i2c_phy *to_tpm_tis_i2c_phy(struct tpm_tis_data *data) > +{ > + return container_of(data, struct tpm_tis_i2c_phy, priv); > +} > + > +static u8 address_to_register(u32 addr) > +{ > + addr &= 0xFFF; > + > + switch (addr) { > + // adapt register addresses that have changed compared to > + // older TIS versions > + case TPM_ACCESS(0): > + return 0x04; > + case TPM_LOC_SEL: > + return 0x00; > + case TPM_DID_VID(0): > + return 0x48; > + case TPM_RID(0): > + return 0x4C; > + default: > + return addr; > + } > +} > + > +static int tpm_tis_i2c_read_bytes(struct tpm_tis_data *data, u32 addr, > + u16 len, u8 *result) > +{ > + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); > + int ret = 0; > + int i = 0; > + u8 reg = address_to_register(addr); > + struct i2c_msg msgs[] = { > + { > + .addr = phy->i2c_client->addr, > + .len = sizeof(reg), > + .buf = ®, > + }, > + { > + .addr = phy->i2c_client->addr, > + .len = len, > + .buf = result, > + .flags = I2C_M_RD, > + }, > + }; > + > + do { > + ret = i2c_transfer(phy->i2c_client->adapter, msgs, > + ARRAY_SIZE(msgs)); > + usleep_range(250, 300); // wait default GUARD_TIME of 250µs > + > + } while (ret < 0 && i++ < TPM_RETRY); > + > + if (ret < 0) > + return ret; > + > + > + return 0; > +} > + > +static int tpm_tis_i2c_write_bytes(struct tpm_tis_data *data, u32 addr, > + u16 len, const u8 *value) > +{ > + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); > + int ret = 0; > + int i = 0; > + > + if (phy->iobuf) { > + if (len > TPM_BUFSIZE - 1) > + return -EIO; > + > + phy->iobuf[0] = address_to_register(addr); > + memcpy(phy->iobuf + 1, value, len); > + > + { > + struct i2c_msg msgs[] = { > + { > + .addr = phy->i2c_client->addr, > + .len = len + 1, > + .buf = phy->iobuf, > + }, > + }; > + > + do { > + ret = i2c_transfer(phy->i2c_client->adapter, > + msgs, ARRAY_SIZE(msgs)); > + // wait default GUARD_TIME of 250µs > + usleep_range(250, 300); > + } while (ret < 0 && i++ < TPM_RETRY); > + } > + } else { > + u8 reg = address_to_register(addr); > + > + struct i2c_msg msgs[] = { > + { > + .addr = phy->i2c_client->addr, > + .len = sizeof(reg), > + .buf = ®, > + }, > + { > + .addr = phy->i2c_client->addr, > + .len = len, > + .buf = (u8 *)value, > + .flags = I2C_M_NOSTART, > + }, > + }; > + do { > + ret = i2c_transfer(phy->i2c_client->adapter, msgs, > + ARRAY_SIZE(msgs)); > + // wait default GUARD_TIME of 250µs > + usleep_range(250, 300); > + } while (ret < 0 && i++ < TPM_RETRY); > + } > + > + if (ret < 0) > + return ret; > + > + > + return 0; > +} > + > +static bool tpm_tis_i2c_check_data(struct tpm_tis_data *data, > + const u8 *buf, size_t len) > +{ > + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); > + u16 crc, crc_tpm; > + int rc; > + > + if (phy->data_csum) { > + crc = crc_ccitt(0x0000, buf, len); > + rc = tpm_tis_read16(data, TPM_DATA_CSUM, &crc_tpm); > + if (rc < 0) > + return false; > + > + crc_tpm = be16_to_cpu(crc_tpm); > + return crc == crc_tpm; > + } > + > + return true; > +} > + > +static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume); > + > +static int csum_state_store(struct tpm_tis_data *data, u8 new_state) > +{ > + struct tpm_tis_i2c_phy *phy = to_tpm_tis_i2c_phy(data); > + u8 cur_state; > + int rc; > + > + rc = tpm_tis_i2c_write_bytes(&phy->priv, TPM_DATA_CSUM_ENABLE, > + 1, &new_state); > + if (rc < 0) > + return rc; > + > + rc = tpm_tis_i2c_read_bytes(&phy->priv, TPM_DATA_CSUM_ENABLE, > + 1, &cur_state); > + if (rc < 0) > + return rc; > + > + if (new_state == cur_state) > + phy->data_csum = (bool)new_state; > + > + return rc; > +} > + > +static const struct tpm_tis_phy_ops tpm_i2c_phy_ops = { > + .read_bytes = tpm_tis_i2c_read_bytes, > + .write_bytes = tpm_tis_i2c_write_bytes, > + .check_data = tpm_tis_i2c_check_data, > +}; > + > +static int tpm_tis_i2c_probe(struct i2c_client *dev, > + const struct i2c_device_id *id) > +{ > + struct tpm_tis_i2c_phy *phy; > + int rc; > + int CRC_Checksum = 0; > + const u8 loc_init = 0; > + struct device_node *np; > + > + phy = devm_kzalloc(&dev->dev, sizeof(struct tpm_tis_i2c_phy), > + GFP_KERNEL); > + if (!phy) > + return -ENOMEM; > + > + phy->i2c_client = dev; > + > + if (!i2c_check_functionality(dev->adapter, I2C_FUNC_NOSTART)) { > + phy->iobuf = devm_kmalloc(&dev->dev, TPM_BUFSIZE, GFP_KERNEL); > + if (!phy->iobuf) > + return -ENOMEM; > + } > + > + // select locality 0 (the driver will access only via locality 0) > + rc = tpm_tis_i2c_write_bytes(&phy->priv, TPM_LOC_SEL, 1, &loc_init); > + if (rc < 0) > + return rc; > + > + // set CRC checksum calculation enable > + np = dev->dev.of_node; > + if (of_property_read_bool(np, "crc-checksum")) > + CRC_Checksum = 1; > + > + rc = csum_state_store(&phy->priv, CRC_Checksum); > + if (rc < 0) > + return rc; > + > + return tpm_tis_core_init(&dev->dev, &phy->priv, -1, &tpm_i2c_phy_ops, > + NULL); > +} > + > +static const struct i2c_device_id tpm_tis_i2c_id[] = { > + {"tpm_tis_i2c", 0}, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, tpm_tis_i2c_id); > + > +static const struct of_device_id of_tis_i2c_match[] = { > + { .compatible = "tcg,tpm-tis-i2c", }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, of_tis_i2c_match); > + > +static const struct acpi_device_id acpi_tis_i2c_match[] = { > + {"SMO0768", 0}, > + {} > +}; > +MODULE_DEVICE_TABLE(acpi, acpi_tis_i2c_match); > + > +static struct i2c_driver tpm_tis_i2c_driver = { > + .driver = { > + .owner = THIS_MODULE, > + .name = "tpm_tis_i2c", > + .pm = &tpm_tis_pm, > + .of_match_table = of_match_ptr(of_tis_i2c_match), > + .acpi_match_table = ACPI_PTR(acpi_tis_i2c_match), > + }, > + .probe = tpm_tis_i2c_probe, > + .id_table = tpm_tis_i2c_id, > +}; > + > +module_i2c_driver(tpm_tis_i2c_driver); > + > +MODULE_DESCRIPTION("TPM Driver for native I2C access"); Just put "TPM Driver" here. /Jarkko