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

[Ilias Apalodimas]

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 at linaro.org>
---
Changes since v1:
- split off the tis core code into a different file
 drivers/tpm/Kconfig         |   9 +++
 drivers/tpm/Makefile        |   1 +
 drivers/tpm/tpm2_tis_mmio.c | 156 ++++++++++++++++++++++++++++++++++++
 3 files changed, 166 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 f64d20067f88..1065c1874f58 100644
--- a/drivers/tpm/Makefile
+++ b/drivers/tpm/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_$(SPL_TPL_)TPM2_CR50_I2C) += cr50_i2c.o
 obj-$(CONFIG_TPM2_TIS_SANDBOX) += tpm2_tis_sandbox.o
 obj-$(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..2183a2807162
--- /dev/null
+++ b/drivers/tpm/tpm2_tis_mmio.c
@@ -0,0 +1,156 @@
+// 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 {
+	unsigned int pcr_count;
+	unsigned int pcr_select_min;
+	unsigned int time_before_first_cmd_ms;
+	void __iomem *iobase;
+};
+
+static int mmio_read_bytes(struct udevice *udev, u32 addr, u16 len,
+			   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);
+	return 0;
+}
+
+static int mmio_read16(struct udevice *udev, u32 addr, u16 *result)
+{
+	struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
+
+	*result = ioread16(drv_data->iobase + addr);
+	return 0;
+}
+
+static int mmio_read32(struct udevice *udev, u32 addr, u32 *result)
+{
+	struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
+
+	*result = ioread32(drv_data->iobase + addr);
+	return 0;
+}
+
+static int mmio_write32(struct udevice *udev, u32 addr, u32 value)
+{
+	struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
+
+	iowrite32(value, drv_data->iobase + addr);
+	return 0;
+}
+
+static struct tpm_tis_phy_ops phy_ops = {
+	.read_bytes = mmio_read_bytes,
+	.write_bytes = mmio_write_bytes,
+	.read16 = mmio_read16,
+	.read32 = mmio_read32,
+	.write32 = mmio_write32,
+};
+
+static int tpm_tis_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 ret = 0;
+	fdt_addr_t ioaddr;
+	u64 sz;
+
+	ioaddr = dev_read_addr(udev);
+	if (ioaddr == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	ret = dev_read_u64(udev, "reg", &sz);
+	if (ret)
+		return -EINVAL;
+
+	drv_data->iobase = ioremap(ioaddr, sz);
+	log_info("Remapped TPM2 base: 0x%llx size: 0x%llx\n", ioaddr, sz);
+	tpm_tis_ops_register(udev, &phy_ops);
+	ret = tpm_tis_init(udev);
+	if (ret)
+		goto iounmap;
+
+	priv->pcr_count = drv_data->pcr_count;
+	priv->pcr_select_min = drv_data->pcr_select_min;
+	/*
+	 * Although the driver probably works with a TPMv1 our Kconfig
+	 * limits the driver to TPMv2 only
+	 */
+	priv->version = TPM_V2;
+
+	return ret;
+iounmap:
+	iounmap(drv_data->iobase);
+	return -EINVAL;
+}
+
+static int tpm_tis_remove(struct udevice *udev)
+{
+	struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(udev);
+
+	iounmap(drv_data->iobase);
+	return tpm_tis_cleanup(udev);
+}
+
+static const struct tpm_ops tpm_tis_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_ids[] = {
+	{
+		.compatible = "tcg,tpm-tis-mmio",
+		.data = (ulong)&tpm_tis_std_chip_data,
+	},
+	{ }
+};
+
+U_BOOT_DRIVER(tpm_tis_mmio) = {
+	.name   = "tpm_tis_mmio",
+	.id     = UCLASS_TPM,
+	.of_match = tpm_tis_ids,
+	.ops    = &tpm_tis_ops,
+	.probe	= tpm_tis_probe,
+	.remove	= tpm_tis_remove,
+	.priv_auto	= sizeof(struct tpm_chip),
+};
-- 
2.32.0.rc0