Re: [PATCH 2/6 v4] tpm2: Add a TPMv2 MMIO TIS driver

Hi Ilias,

On Wed, 3 Nov 2021 at 09:09, Ilias Apalodimas ilias.apalodimas@linaro.org wrote:

Add support for devices that expose a TPMv2 though MMIO. Apart from those devices, we can use the driver in our QEMU setups and test TPM related code which is difficult to achieve using the sandbox driver (e.g test the EFI TCG2 protocol).

It's worth noting that a previous patch added TPMv2 TIS core functions, which the current driver is consuming.

Signed-off-by: Ilias Apalodimas ilias.apalodimas@linaro.org

drivers/tpm/Kconfig | 9 +++ drivers/tpm/Makefile | 1 + drivers/tpm/tpm2_tis_mmio.c | 152 ++++++++++++++++++++++++++++++++++++ 3 files changed, 162 insertions(+) create mode 100644 drivers/tpm/tpm2_tis_mmio.c

diff --git a/drivers/tpm/Kconfig b/drivers/tpm/Kconfig index 9eebab5cfd90..406ee8716e1e 100644 --- a/drivers/tpm/Kconfig +++ b/drivers/tpm/Kconfig @@ -161,6 +161,15 @@ config TPM2_FTPM_TEE help This driver supports firmware TPM running in TEE.

+config TPM2_MMIO

•   bool "MMIO based TPM2 Interface"
  

•   depends on TPM_V2
  

•   help
  

•     This driver supports firmware TPM2.0 MMIO interface.
  

•     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 diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile index c65be5267002..494aa5a46d30 100644 --- a/drivers/tpm/Makefile +++ b/drivers/tpm/Makefile @@ -14,3 +14,4 @@ obj-$(CONFIG_$(SPL_TPL_)TPM2_CR50_I2C) += cr50_i2c.o obj-$(CONFIG_TPM2_TIS_SANDBOX) += tpm2_tis_sandbox.o sandbox_common.o obj-$(CONFIG_TPM2_TIS_SPI) += tpm2_tis_spi.o obj-$(CONFIG_TPM2_FTPM_TEE) += tpm2_ftpm_tee.o +obj-$(CONFIG_TPM2_MMIO) += tpm2_tis_core.o tpm2_tis_mmio.o diff --git a/drivers/tpm/tpm2_tis_mmio.c b/drivers/tpm/tpm2_tis_mmio.c new file mode 100644 index 000000000000..3bd0b0871a83 --- /dev/null +++ b/drivers/tpm/tpm2_tis_mmio.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • driver for mmio TCG/TIS TPM (trusted platform module).
• • Specifications at www.trustedcomputinggroup.org
• */

+#include <common.h> +#include <dm.h> +#include <log.h> +#include <tpm-v2.h> +#include <linux/bitops.h> +#include <linux/compiler.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/io.h> +#include <linux/unaligned/be_byteshift.h> +#include "tpm_tis.h" +#include "tpm_internal.h"

+/**

• • struct tpm_tis_chip_data - Information about an MMIO TPM
• • @pcr_count: Number of PCR per bank
• • @pcr_select_min: Minimum size in bytes of the pcrSelect array
• • @iobase: Base address
• */

+struct tpm_tis_chip_data {

•   unsigned int pcr_count;
  

•   unsigned int pcr_select_min;
  

•   void __iomem *iobase;
  

+};

+static int mmio_read_bytes(struct udevice *udev, u32 addr, u16 len,

dev again

•                      u8 *result)
  

+{

•   struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
  

•   while (len--)
  

•           *result++ = ioread8(drv_data->iobase + addr);
  

•   return 0;
  

+}

+static int mmio_write_bytes(struct udevice *udev, u32 addr, u16 len,

•                       const u8 *value)
  

+{

•   struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
  

•   while (len--)
  

•           iowrite8(*value++, drv_data->iobase + addr);
  

So should this use regmap?

•   return 0;
  

+}

[..]

Regards, Simon