Merge tag 'tee-drv-misc-for-v4.17' of https://git.linaro.org:/people/jens.wiklander/linux-tee into next/drivers

Pull "Small fix and report OP-TEE revision information" from Jens Wiklander:

* Adds one small fix correct max value of privileged device id allocation,
  this is only needed if there's more than TEE_NUM_DEVICES / 2 (16) tee
  drivers registered. One or two is a normal value.
* Reports OP-TEE revision information (major, minro version and build id
  if available)

* tag 'tee-drv-misc-for-v4.17' of https://git.linaro.org:/people/jens.wiklander/linux-tee:
  tee: optee: report OP-TEE revision information
  tee: optee: GET_OS_REVISION: document a2 as a build identifier
  tee: correct max value for id allocation

3 files changed, 41 insertions, 6 deletions

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index e9843c53fe31..e5fd5ed217da 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -356,6 +356,27 @@ static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn)
 	return false;
 }
 
+static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn)
+{
+	union {
+		struct arm_smccc_res smccc;
+		struct optee_smc_call_get_os_revision_result result;
+	} res = {
+		.result = {
+			.build_id = 0
+		}
+	};
+
+	invoke_fn(OPTEE_SMC_CALL_GET_OS_REVISION, 0, 0, 0, 0, 0, 0, 0,
+		  &res.smccc);
+
+	if (res.result.build_id)
+		pr_info("revision %lu.%lu (%08lx)", res.result.major,
+			res.result.minor, res.result.build_id);
+	else
+		pr_info("revision %lu.%lu", res.result.major, res.result.minor);
+}
+
 static bool optee_msg_api_revision_is_compatible(optee_invoke_fn *invoke_fn)
 {
 	union {
@@ -547,6 +568,8 @@ static struct optee *optee_probe(struct device_node *np)
 		return ERR_PTR(-EINVAL);
 	}
 
+	optee_msg_get_os_revision(invoke_fn);
+
 	if (!optee_msg_api_revision_is_compatible(invoke_fn)) {
 		pr_warn("api revision mismatch\n");
 		return ERR_PTR(-EINVAL);
diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h
index 7cd327243ada..bbf0cf028c16 100644
--- a/drivers/tee/optee/optee_smc.h
+++ b/drivers/tee/optee/optee_smc.h
@@ -112,12 +112,20 @@ struct optee_smc_calls_revision_result {
  * Trusted OS, not of the API.
  *
  * Returns revision in a0-1 in the same way as OPTEE_SMC_CALLS_REVISION
- * described above.
+ * described above. May optionally return a 32-bit build identifier in a2,
+ * with zero meaning unspecified.
  */
 #define OPTEE_SMC_FUNCID_GET_OS_REVISION OPTEE_MSG_FUNCID_GET_OS_REVISION
 #define OPTEE_SMC_CALL_GET_OS_REVISION \
 	OPTEE_SMC_FAST_CALL_VAL(OPTEE_SMC_FUNCID_GET_OS_REVISION)
 
+struct optee_smc_call_get_os_revision_result {
+	unsigned long major;
+	unsigned long minor;
+	unsigned long build_id;
+	unsigned long reserved1;
+};
+
 /*
  * Call with struct optee_msg_arg as argument
  *
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 6c4b200a4560..0124a91c8d71 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -693,7 +693,7 @@ struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 {
 	struct tee_device *teedev;
 	void *ret;
-	int rc;
+	int rc, max_id;
 	int offs = 0;
 
 	if (!teedesc || !teedesc->name || !teedesc->ops ||
@@ -707,16 +707,20 @@ struct tee_device *tee_device_alloc(const struct tee_desc *teedesc,
 		goto err;
 	}
 
-	if (teedesc->flags & TEE_DESC_PRIVILEGED)
+	max_id = TEE_NUM_DEVICES / 2;
+
+	if (teedesc->flags & TEE_DESC_PRIVILEGED) {
 		offs = TEE_NUM_DEVICES / 2;
+		max_id = TEE_NUM_DEVICES;
+	}
 
 	spin_lock(&driver_lock);
-	teedev->id = find_next_zero_bit(dev_mask, TEE_NUM_DEVICES, offs);
-	if (teedev->id < TEE_NUM_DEVICES)
+	teedev->id = find_next_zero_bit(dev_mask, max_id, offs);
+	if (teedev->id < max_id)
 		set_bit(teedev->id, dev_mask);
 	spin_unlock(&driver_lock);
 
-	if (teedev->id >= TEE_NUM_DEVICES) {
+	if (teedev->id >= max_id) {
 		ret = ERR_PTR(-ENOMEM);
 		goto err;
 	}