Qualcomm TEE (QTEE) hosts Trusted Applications (TAs) and services in the secure world, accessed via objects. A QTEE client can invoke these objects to request services. Similarly, QTEE can request services from the nonsecure world using objects exported to the secure world.
Add low-level primitives to facilitate the invocation of objects hosted in QTEE, as well as those hosted in the nonsecure world.
If support for object invocation is available, the qcom_scm allocates a dedicated child platform device. The driver for this device communicates with QTEE using low-level primitives.
Tested-by: Neil Armstrong neil.armstrong@linaro.org Signed-off-by: Amirreza Zarrabi amirreza.zarrabi@oss.qualcomm.com --- drivers/firmware/qcom/qcom_scm.c | 128 +++++++++++++++++++++++++++++++++ drivers/firmware/qcom/qcom_scm.h | 7 ++ include/linux/firmware/qcom/qcom_scm.h | 6 ++ 3 files changed, 141 insertions(+)
diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c index f63b716be5b0..e3207a9d2de6 100644 --- a/drivers/firmware/qcom/qcom_scm.c +++ b/drivers/firmware/qcom/qcom_scm.c @@ -2087,6 +2087,124 @@ static int qcom_scm_qseecom_init(struct qcom_scm *scm)
#endif /* CONFIG_QCOM_QSEECOM */
+/** + * qcom_scm_qtee_invoke_smc() - Invoke a QTEE object. + * @inbuf: start address of memory area used for inbound buffer. + * @inbuf_size: size of the memory area used for inbound buffer. + * @outbuf: start address of memory area used for outbound buffer. + * @outbuf_size: size of the memory area used for outbound buffer. + * @result: result of QTEE object invocation. + * @response_type: response type returned by QTEE. + * + * @response_type determines how the contents of @inbuf and @outbuf + * should be processed. + * + * Return: On success, return 0 or <0 on failure. + */ +int qcom_scm_qtee_invoke_smc(phys_addr_t inbuf, size_t inbuf_size, + phys_addr_t outbuf, size_t outbuf_size, + u64 *result, u64 *response_type) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_SMCINVOKE, + .cmd = QCOM_SCM_SMCINVOKE_INVOKE, + .owner = ARM_SMCCC_OWNER_TRUSTED_OS, + .args[0] = inbuf, + .args[1] = inbuf_size, + .args[2] = outbuf, + .args[3] = outbuf_size, + .arginfo = QCOM_SCM_ARGS(4, QCOM_SCM_RW, QCOM_SCM_VAL, + QCOM_SCM_RW, QCOM_SCM_VAL), + }; + struct qcom_scm_res res; + int ret; + + ret = qcom_scm_call(__scm->dev, &desc, &res); + if (ret) + return ret; + + *response_type = res.result[0]; + *result = res.result[1]; + + return 0; +} +EXPORT_SYMBOL(qcom_scm_qtee_invoke_smc); + +/** + * qcom_scm_qtee_callback_response() - Submit response for callback request. + * @buf: start address of memory area used for outbound buffer. + * @buf_size: size of the memory area used for outbound buffer. + * @result: Result of QTEE object invocation. + * @response_type: Response type returned by QTEE. + * + * @response_type determines how the contents of @buf should be processed. + * + * Return: On success, return 0 or <0 on failure. + */ +int qcom_scm_qtee_callback_response(phys_addr_t buf, size_t buf_size, + u64 *result, u64 *response_type) +{ + struct qcom_scm_desc desc = { + .svc = QCOM_SCM_SVC_SMCINVOKE, + .cmd = QCOM_SCM_SMCINVOKE_CB_RSP, + .owner = ARM_SMCCC_OWNER_TRUSTED_OS, + .args[0] = buf, + .args[1] = buf_size, + .arginfo = QCOM_SCM_ARGS(2, QCOM_SCM_RW, QCOM_SCM_VAL), + }; + struct qcom_scm_res res; + int ret; + + ret = qcom_scm_call(__scm->dev, &desc, &res); + if (ret) + return ret; + + *response_type = res.result[0]; + *result = res.result[1]; + + return 0; +} +EXPORT_SYMBOL(qcom_scm_qtee_callback_response); + +static void qcom_scm_qtee_free(void *data) +{ + struct platform_device *qtee_dev = data; + + platform_device_unregister(qtee_dev); +} + +static int qcom_scm_qtee_init(struct qcom_scm *scm) +{ + struct platform_device *qtee_dev; + u64 result, response_type; + int ret; + + /* + * Check if QTEE supports smcinvoke: + * This will fail with -EINVAL due to invalid buffers, but first, + * it checks whether the call is supported in QTEE syscall handler. + * If not supported, -EIO is returned. + */ + ret = qcom_scm_qtee_invoke_smc(0, 0, 0, 0, &result, &response_type); + if (ret == -EIO) + return -EIO; + + /* Setup QTEE interface device. */ + qtee_dev = platform_device_alloc("qcomtee", -1); + if (!qtee_dev) + return -ENOMEM; + + qtee_dev->dev.parent = scm->dev; + + ret = platform_device_add(qtee_dev); + if (ret) { + platform_device_put(qtee_dev); + return ret; + } + + return devm_add_action_or_reset(scm->dev, qcom_scm_qtee_free, qtee_dev); +} + /** * qcom_scm_is_available() - Checks if SCM is available */ @@ -2322,6 +2440,16 @@ static int qcom_scm_probe(struct platform_device *pdev) ret = qcom_scm_qseecom_init(scm); WARN(ret < 0, "failed to initialize qseecom: %d\n", ret);
+ /* + * Initialize the QTEE object interface. + * + * This only represents the availability for QTEE object invocation + * and callback support. On failure, ignore the result. Any subsystem + * depending on it may fail if it tries to access this interface. + */ + ret = qcom_scm_qtee_init(scm); + WARN(ret < 0, "failed to initialize qcomtee: %d\n", ret); + return 0;
err: diff --git a/drivers/firmware/qcom/qcom_scm.h b/drivers/firmware/qcom/qcom_scm.h index 3133d826f5fa..665e21feec9b 100644 --- a/drivers/firmware/qcom/qcom_scm.h +++ b/drivers/firmware/qcom/qcom_scm.h @@ -155,6 +155,13 @@ struct qcom_tzmem_pool *qcom_scm_get_tzmem_pool(void); #define QCOM_SCM_SVC_GPU 0x28 #define QCOM_SCM_SVC_GPU_INIT_REGS 0x01
+/* ARM_SMCCC_OWNER_TRUSTED_OS calls */ + +#define QCOM_SCM_SVC_SMCINVOKE 0x06 +#define QCOM_SCM_SMCINVOKE_INVOKE_LEGACY 0x00 +#define QCOM_SCM_SMCINVOKE_CB_RSP 0x01 +#define QCOM_SCM_SMCINVOKE_INVOKE 0x02 + /* common error codes */ #define QCOM_SCM_V2_EBUSY -12 #define QCOM_SCM_ENOMEM -5 diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h index 983e1591bbba..b3a7cc20e617 100644 --- a/include/linux/firmware/qcom/qcom_scm.h +++ b/include/linux/firmware/qcom/qcom_scm.h @@ -176,4 +176,10 @@ static inline int qcom_scm_qseecom_app_send(u32 app_id,
#endif /* CONFIG_QCOM_QSEECOM */
+int qcom_scm_qtee_invoke_smc(phys_addr_t inbuf, size_t inbuf_size, + phys_addr_t outbuf, size_t outbuf_size, + u64 *result, u64 *response_type); +int qcom_scm_qtee_callback_response(phys_addr_t buf, size_t buf_size, + u64 *result, u64 *response_type); + #endif