Change optee driver service enumeration to not enumerate (and allocate a zero sized shared memory buffer) when OP-TEE reports that there is no service to enumerate.

This change fixes an existing issue that occurs when the such zero sized shared memory buffer allocated from malloc() has a physical address of offset 0 of a physical 4kB page. In such case, OP-TEE secure world refuses to register the zero-sized shared memory area and makes U-Boot optee service enumeration to fail.

Fixes: 94ccfb78a4d6 ("drivers: tee: optee: discover OP-TEE services") Signed-off-by: Etienne Carriere etienne.carriere@foss.st.com --- drivers/tee/optee/core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c index 5308dd58ce..47f845cffe 100644 --- a/drivers/tee/optee/core.c +++ b/drivers/tee/optee/core.c @@ -139,6 +139,11 @@ static int enum_services(struct udevice *dev, struct tee_shm **shm, size_t *coun if (ret) return ret;

+ if (!shm_size) { + *count = 0; + return 0; + } + ret = tee_shm_alloc(dev, shm_size, 0, shm); if (ret) { dev_err(dev, "Failed to allocated shared memory: %d\n", ret); @@ -185,14 +190,15 @@ static int bind_service_drivers(struct udevice *dev)

ret = enum_services(dev, &service_list, &service_count, tee_sess, PTA_CMD_GET_DEVICES); - if (!ret) + if (!ret && service_count) ret = bind_service_list(dev, service_list, service_count);

tee_shm_free(service_list); + service_list = NULL;

ret2 = enum_services(dev, &service_list, &service_count, tee_sess, PTA_CMD_GET_DEVICES_SUPP); - if (!ret2) + if (!ret2 && service_count) ret2 = bind_service_list(dev, service_list, service_count);

tee_shm_free(service_list);

On 11/29/23 13:37, Etienne Carriere wrote:

Change optee probe function to only warn when service enumeration sequence fails instead of reporting an optee driver probe failure. Indeed U-Boot can still use OP-TEE even if some OP-TEE services are not discovered.

Fixes: 94ccfb78a4d6 ("drivers: tee: optee: discover OP-TEE services") Signed-off-by: Etienne Carriere etienne.carriere@foss.st.com

---

drivers/tee/optee/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c index 9a9b697e91..5308dd58ce 100644 --- a/drivers/tee/optee/core.c +++ b/drivers/tee/optee/core.c @@ -841,7 +841,7 @@ static int optee_probe(struct udevice *dev) if (IS_ENABLED(CONFIG_OPTEE_SERVICE_DISCOVERY)) { ret = bind_service_drivers(dev); if (ret)

• 	return ret;
  

• 	dev_warn(dev, "optee service enumeration failed: %d\n", ret);
  

  } else if (IS_ENABLED(CONFIG_RNG_OPTEE)) { /*
  • Discovery of TAs on the TEE bus is not supported in U-Boot:

Reviewed-by: Patrice Chotard patrice.chotard@foss.st.com

Thanks Patrice