On Fri, 29 May 2020 at 13:57, Maxim Uvarov maxim.uvarov@linaro.org wrote:

Some drivers (like ftpm) can operate only after tee-supplicant runs because of tee-supplicant provides things like storage services. This patch splits probe of non tee-supplicant dependable drivers to the early stage, and after tee-supplicant run probe other drivers.

Signed-off-by: Maxim Uvarov maxim.uvarov@linaro.org Suggested-by: Sumit Garg sumit.garg@linaro.org Suggested-by: Arnd Bergmann arnd@linaro.org

---

drivers/tee/optee/core.c | 24 +++++++++++++++++++++--- drivers/tee/optee/device.c | 17 +++++++++++------ drivers/tee/optee/optee_private.h | 10 +++++++++- 3 files changed, 41 insertions(+), 10 deletions(-)

Commit subject sounds a little vague, so how about:

==== optee: enable support for multi-stage bus enumeration ====

Then in the commit description, you can elaborate on what it actually means.

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c index 99698b8a3a74..bf0851fdf108 100644 --- a/drivers/tee/optee/core.c +++ b/drivers/tee/optee/core.c @@ -17,6 +17,7 @@ #include <linux/tee_drv.h> #include <linux/types.h> #include <linux/uaccess.h> +#include <linux/workqueue.h> #include "optee_private.h" #include "optee_smc.h" #include "shm_pool.h" @@ -218,6 +219,11 @@ static void optee_get_version(struct tee_device *teedev, *vers = v; }

+static void optee_bus_scan(struct work_struct *work) +{

•   WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
  

+}

static int optee_open(struct tee_context *ctx) { struct optee_context_data *ctxdata; @@ -241,8 +247,18 @@ static int optee_open(struct tee_context *ctx) kfree(ctxdata); return -EBUSY; }

•   }
  
  

•           if (!optee->scan_bus_done) {
  

•                   INIT_WORK(&optee->scan_bus_work, optee_bus_scan);
  

•                   optee->scan_bus_wq = create_workqueue("optee_bus_scan");
  

•                   if (!optee->scan_bus_wq) {
  

•                           kfree(ctxdata);
  

•                           return -ECHILD;
  

•                   }
  

•                   queue_work(optee->scan_bus_wq, &optee->scan_bus_work);
  

•                   optee->scan_bus_done = true;
  

•           }
  

•   }
    mutex_init(&ctxdata->mutex);
    INIT_LIST_HEAD(&ctxdata->sess_list);
  
  

@@ -296,8 +312,10 @@ static void optee_release(struct tee_context *ctx)

    ctx->data = NULL;

•   if (teedev == optee->supp_teedev)
  

•   if (teedev == optee->supp_teedev) {
  

•           destroy_workqueue(optee->scan_bus_wq);
  

Doesn't it deserve a prior check "if(optee->scan_bus_wq)" as we only allocate it once during multiple tee-supplicant instances?

            optee_supp_release(&optee->supp);

•   }
  

}

static const struct tee_driver_ops optee_ops = { @@ -675,7 +693,7 @@ static int optee_probe(struct platform_device *pdev)

    platform_set_drvdata(pdev, optee);

•   rc = optee_enumerate_devices();
  

•   rc = optee_enumerate_devices(PTA_CMD_GET_DEVICES);
    if (rc) {
            optee_remove(pdev);
            return rc;
  

diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c index e3a148521ec1..d4931dad07aa 100644 --- a/drivers/tee/optee/device.c +++ b/drivers/tee/optee/device.c @@ -21,7 +21,6 @@

• TEE_ERROR_BAD_PARAMETERS - Incorrect input param
• TEE_ERROR_SHORT_BUFFER - Output buffer size less than required

*/

This comment needs to be moved as well.

-#define PTA_CMD_GET_DEVICES 0x0

static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) { @@ -32,7 +31,8 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) }

static int get_devices(struct tee_context *ctx, u32 session,

•                  struct tee_shm *device_shm, u32 *shm_size)
  

•                  struct tee_shm *device_shm, u32 *shm_size,
  

•                  u32 func)
  

{ int ret = 0; struct tee_ioctl_invoke_arg inv_arg; @@ -42,7 +42,7 @@ static int get_devices(struct tee_context *ctx, u32 session, memset(&param, 0, sizeof(param));

    /* Invoke PTA_CMD_GET_DEVICES function */

You can get rid of this comment.

-Sumit

•   inv_arg.func = PTA_CMD_GET_DEVICES;
  

•   inv_arg.func = func;
    inv_arg.session = session;
    inv_arg.num_params = 4;
  
  

@@ -87,7 +87,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id) return rc; }

-int optee_enumerate_devices(void) +static int __optee_enumerate_devices(u32 func) { const uuid_t pta_uuid = UUID_INIT(0x7011a688, 0xddde, 0x4053, @@ -118,7 +118,7 @@ int optee_enumerate_devices(void) goto out_ctx; }

•   rc = get_devices(ctx, sess_arg.session, NULL, &shm_size);
  

•   rc = get_devices(ctx, sess_arg.session, NULL, &shm_size, func);
    if (rc < 0 || !shm_size)
            goto out_sess;
  
  

@@ -130,7 +130,7 @@ int optee_enumerate_devices(void) goto out_sess; }

•   rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size);
  

•   rc = get_devices(ctx, sess_arg.session, device_shm, &shm_size, func);
    if (rc < 0)
            goto out_shm;
  
  

@@ -158,3 +158,8 @@ int optee_enumerate_devices(void)

    return rc;

}

+int optee_enumerate_devices(u32 func) +{

•   return  __optee_enumerate_devices(func);
  

+} diff --git a/drivers/tee/optee/optee_private.h b/drivers/tee/optee/optee_private.h index d9c5037b4e03..8b71839a357e 100644 --- a/drivers/tee/optee/optee_private.h +++ b/drivers/tee/optee/optee_private.h @@ -78,6 +78,9 @@ struct optee_supp {

• @memremaped_shm virtual address of memory in shared memory pool
• @sec_caps: secure world capabilities defined by

•                 OPTEE_SMC_SEC_CAP_* in optee_smc.h
  

• • @scan_bus_done flag if device registation was already done.
• • @scan_bus_wq workqueue to scan optee bus and register optee drivers
• • @scan_bus_work workq to scan optee bus and register optee drivers
  */

struct optee { struct tee_device *supp_teedev; @@ -89,6 +92,9 @@ struct optee { struct tee_shm_pool *pool; void *memremaped_shm; u32 sec_caps;

•   bool   scan_bus_done;
  

•   struct workqueue_struct *scan_bus_wq;
  

•   struct work_struct scan_bus_work;
  

};

struct optee_session { @@ -173,7 +179,9 @@ void optee_free_pages_list(void *array, size_t num_entries); void optee_fill_pages_list(u64 *dst, struct page **pages, int num_pages, size_t page_offset);

-int optee_enumerate_devices(void); +#define PTA_CMD_GET_DEVICES 0x0 +#define PTA_CMD_GET_DEVICES_SUPP 0x1 +int optee_enumerate_devices(u32 func);

/*

• Small helpers

-- 2.17.1

On Fri, 29 May 2020 at 13:57, Maxim Uvarov maxim.uvarov@linaro.org wrote:

OP-TEE device names for sysfs need to be unique and it's better if they will mean something. UUID for name looks like good solution: /sys/bus/tee/devices/optee-ta-<uuid>

I think this description is a little vague here which fails to explain why we are doing this. How about:

======= With the evolving use-cases for TEE bus, now it's required to support multi-stage enumeration process. But using a simple index doesn't suffice this requirement and instead leads to duplicate sysfs entries. So instead switch to use more informative device UUID for sysfs entry like:

/sys/bus/tee/devices/optee-ta-<uuid> ========

Signed-off-by: Maxim Uvarov maxim.uvarov@linaro.org

Documentation/ABI/testing/sysfs-bus-optee-devices | 8 ++++++++ MAINTAINERS | 2 ++ drivers/tee/optee/device.c | 6 +++--- 3 files changed, 13 insertions(+), 3 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-optee-devices

I think this patch belongs as patch #1 in this series given the dependency.

diff --git a/Documentation/ABI/testing/sysfs-bus-optee-devices b/Documentation/ABI/testing/sysfs-bus-optee-devices new file mode 100644 index 000000000000..0ae04ae5374a --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-optee-devices @@ -0,0 +1,8 @@ +What: /sys/bus/tee/devices/optee-ta-<uuid>/ +Date: May 2020 +KernelVersion 5.7 +Contact: tee-dev@lists.linaro.org +Description:

•           OP-TEE bus provides reference to registered drivers under this directory. The <uuid>
  

•           matches Trusted Application (TA) driver and corresponding TA in secure OS. Drivers
  

•           are free to create needed API under optee-ta-<uuid> directory.
  

diff --git a/MAINTAINERS b/MAINTAINERS index ecc0749810b0..52717ede29fc 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12516,8 +12516,10 @@ OP-TEE DRIVER M: Jens Wiklander jens.wiklander@linaro.org L: tee-dev@lists.linaro.org S: Maintained +F: Documentation/ABI/testing/sysfs-bus-optee-devices F: drivers/tee/optee/

Unnecessary blank line.

-Sumit

OP-TEE RANDOM NUMBER GENERATOR (RNG) DRIVER M: Sumit Garg sumit.garg@linaro.org L: tee-dev@lists.linaro.org diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c index d4931dad07aa..2eb1c0283aec 100644 --- a/drivers/tee/optee/device.c +++ b/drivers/tee/optee/device.c @@ -65,7 +65,7 @@ static int get_devices(struct tee_context *ctx, u32 session, return 0; }

-static int optee_register_device(const uuid_t *device_uuid, u32 device_id) +static int optee_register_device(const uuid_t *device_uuid) { struct tee_client_device *optee_device = NULL; int rc; @@ -75,7 +75,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id) return -ENOMEM;

    optee_device->dev.bus = &tee_bus_type;

•   dev_set_name(&optee_device->dev, "optee-clnt%u", device_id);
  

•   dev_set_name(&optee_device->dev, "optee-ta-%pUl", device_uuid);
    uuid_copy(&optee_device->id.uuid, device_uuid);
  
    rc = device_register(&optee_device->dev);
  

@@ -144,7 +144,7 @@ static int __optee_enumerate_devices(u32 func) num_devices = shm_size / sizeof(uuid_t);

    for (idx = 0; idx < num_devices; idx++) {

•           rc = optee_register_device(&device_uuid[idx], idx);
  

•           rc = optee_register_device(&device_uuid[idx]);
            if (rc)
                    goto out_shm;
    }
  

-- 2.17.1

On Fri, 29 May 2020 at 13:57, Maxim Uvarov maxim.uvarov@linaro.org wrote:

Register driver on the TEE bus. The module tee registers bus, and module optee calls optee_enumerate_devices() to scan all devices on the bus. Trusted Application for this driver can be Early TA's (can be compiled into optee-os). In that case it will be on OPTEE bus before linux booting. Also optee-suplicant application is needed to be loaded between OPTEE module and ftpm module to maintain functionality for fTPM driver.

I think this description merely describes the functioning of TEE bus and misses what value add does TEE bus provide compared to platform bus.

Consider:

==== OP-TEE based fTPM Trusted Application depends on tee-supplicant to provide NV RAM implementation based on RPMB secure storage. So this dependency can be resolved via TEE bus where we only invoke fTPM driver probe once fTPM device is registered on the bus which is only true after the tee-supplicant is up and running. Additionally, TEE bus provides auto device enumeration. ====

With that, implementation looks good to me. So feel free to add:

Reviewed-by: Sumit Garg sumit.garg@linaro.org

-Sumit

Signed-off-by: Maxim Uvarov maxim.uvarov@linaro.org Suggested-by: Sumit Garg sumit.garg@linaro.org Suggested-by: Arnd Bergmann arnd@linaro.org

---

drivers/char/tpm/tpm_ftpm_tee.c | 70 ++++++++++++++++++++++++++++----- 1 file changed, 60 insertions(+), 10 deletions(-)

diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c index 22bf553ccf9d..28da638360d8 100644 --- a/drivers/char/tpm/tpm_ftpm_tee.c +++ b/drivers/char/tpm/tpm_ftpm_tee.c @@ -214,11 +214,10 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)

• Return:

• On success, 0. On failure, -errno.
  

*/ -static int ftpm_tee_probe(struct platform_device *pdev) +static int ftpm_tee_probe(struct device *dev) { int rc; struct tpm_chip *chip;

•   struct device *dev = &pdev->dev;
    struct ftpm_tee_private *pvt_data = NULL;
    struct tee_ioctl_open_session_arg sess_arg;
  
  

@@ -297,6 +296,13 @@ static int ftpm_tee_probe(struct platform_device *pdev) return rc; }

+static int ftpm_plat_tee_probe(struct platform_device *pdev) +{

•   struct device *dev = &pdev->dev;
  

•   return ftpm_tee_probe(dev);
  

+}

/**

• ftpm_tee_remove() - remove the TPM device
• @pdev: the platform_device description.

@@ -304,9 +310,9 @@ static int ftpm_tee_probe(struct platform_device *pdev)

• Return:

• 0 always.
  

*/ -static int ftpm_tee_remove(struct platform_device *pdev) +static int ftpm_tee_remove(struct device *dev) {

•   struct ftpm_tee_private *pvt_data = dev_get_drvdata(&pdev->dev);
  

•   struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
  
    /* Release the chip */
    tpm_chip_unregister(pvt_data->chip);
  

@@ -328,11 +334,18 @@ static int ftpm_tee_remove(struct platform_device *pdev) return 0; }

+static int ftpm_plat_tee_remove(struct platform_device *pdev) +{

•   struct device *dev = &pdev->dev;
  

•   return ftpm_tee_remove(dev);
  

+}

/**

• ftpm_tee_shutdown() - shutdown the TPM device
• @pdev: the platform_device description.

*/ -static void ftpm_tee_shutdown(struct platform_device *pdev) +static void ftpm_plat_tee_shutdown(struct platform_device *pdev) { struct ftpm_tee_private *pvt_data = dev_get_drvdata(&pdev->dev);

@@ -347,17 +360,54 @@ static const struct of_device_id of_ftpm_tee_ids[] = { }; MODULE_DEVICE_TABLE(of, of_ftpm_tee_ids);

-static struct platform_driver ftpm_tee_driver = { +static struct platform_driver ftpm_tee_plat_driver = { .driver = { .name = "ftpm-tee", .of_match_table = of_match_ptr(of_ftpm_tee_ids), },

•   .probe = ftpm_tee_probe,
  

•   .remove = ftpm_tee_remove,
  

•   .shutdown = ftpm_tee_shutdown,
  

•   .shutdown = ftpm_plat_tee_shutdown,
  

•   .probe = ftpm_plat_tee_probe,
  

•   .remove = ftpm_plat_tee_remove,
  

+};

+/* UUID of the fTPM TA */ +static const struct tee_client_device_id optee_ftpm_id_table[] = {

•   {UUID_INIT(0xbc50d971, 0xd4c9, 0x42c4,
  

•              0x82, 0xcb, 0x34, 0x3f, 0xb7, 0xf3, 0x78, 0x96)},
  

•   {}
  

};

-module_platform_driver(ftpm_tee_driver); +MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);

+static struct tee_client_driver ftpm_tee_driver = {

•   .id_table       = optee_ftpm_id_table,
  

•   .driver         = {
  

•           .name           = "optee-ftpm",
  

•           .bus            = &tee_bus_type,
  

•           .probe          = ftpm_tee_probe,
  

•           .remove         = ftpm_tee_remove,
  

•   },
  

+};

+static int __init ftpm_mod_init(void) +{

•   int rc;
  

•   rc = platform_driver_register(&ftpm_tee_plat_driver);
  

•   if (rc)
  

•           return rc;
  

•   return driver_register(&ftpm_tee_driver.driver);
  

+}

+static void __exit ftpm_mod_exit(void) +{

•   platform_driver_unregister(&ftpm_tee_plat_driver);
  

•   driver_unregister(&ftpm_tee_driver.driver);
  

+}

+module_init(ftpm_mod_init); +module_exit(ftpm_mod_exit);

MODULE_AUTHOR("Thirupathaiah Annapureddy thiruan@microsoft.com"); MODULE_DESCRIPTION("TPM Driver for fTPM TA in TEE"); -- 2.17.1