firmware: stratix10-svc: Add support for async communication

Introduce support for asynchronous communication with the Stratix10
service channel. Define new structures to enable asynchronous messaging
with the Secure Device Manager (SDM). Add and remove asynchronous
support for existing channels. Implement initialization and cleanup
routines for the asynchronous framework. Enable sending and polling of
messages to the SDM asynchronously.

The new public functions added are:
- stratix10_svc_add_async_client: Adds a client to the service channel.
- stratix10_svc_remove_async_client: Removes an asynchronous client from
        the service channel.
- stratix10_svc_async_send: Sends an asynchronous message to the SDM
        mailbox in EL3 secure firmware.
- stratix10_svc_async_poll: Polls the status of an asynchronous service
        request in EL3 secure firmware.
- stratix10_svc_async_done: Marks an asynchronous transaction as
        complete and frees up the resources.

These changes enhance the functionality of the Stratix10 service channel
by allowing for more efficient and flexible communication with the
firmware.

Signed-off-by: Mahesh Rao <mahesh.rao@altera.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach@altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>

2 files changed, 113 insertions, 0 deletions

diff --git a/include/linux/firmware/intel/stratix10-smc.h b/include/linux/firmware/intel/stratix10-smc.h
index 7306dd243b2a..3995d5d70cce 100644
--- a/include/linux/firmware/intel/stratix10-smc.h
+++ b/include/linux/firmware/intel/stratix10-smc.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2017-2018, Intel Corporation
+ * Copyright (C) 2025, Altera Corporation
  */
 
 #ifndef __STRATIX10_SMC_H
@@ -47,6 +48,10 @@
 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_64, \
 	ARM_SMCCC_OWNER_SIP, (func_num))
 
+#define INTEL_SIP_SMC_ASYNC_VAL(func_name)	\
+	ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL, ARM_SMCCC_SMC_64, \
+	ARM_SMCCC_OWNER_SIP, (func_name))
+
 /**
  * Return values in INTEL_SIP_SMC_* call
  *
@@ -654,4 +659,24 @@ INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_FPGA_CONFIG_COMPLETED_WRITE)
 #define INTEL_SIP_SMC_HWMON_READVOLT \
 	INTEL_SIP_SMC_FAST_CALL_VAL(INTEL_SIP_SMC_FUNCID_HWMON_READVOLT)
 
+/**
+ * Request INTEL_SIP_SMC_ASYNC_POLL
+ * Async call used by service driver at EL1 to query mailbox response from SDM.
+ *
+ * Call register usage:
+ * a0 INTEL_SIP_SMC_ASYNC_POLL
+ * a1 transaction job id
+ * a2-17 will be used to return the response data
+ *
+ * Return status
+ * a0 INTEL_SIP_SMC_STATUS_OK
+ * a1-17 will contain the response values from mailbox for the previous send
+ * transaction
+ * Or
+ * a0 INTEL_SIP_SMC_STATUS_NO_RESPONSE
+ * a1-17 not used
+ */
+#define INTEL_SIP_SMC_ASYNC_FUNC_ID_POLL (0xC8)
+#define INTEL_SIP_SMC_ASYNC_POLL \
+	INTEL_SIP_SMC_ASYNC_VAL(INTEL_SIP_SMC_ASYNC_FUNC_ID_POLL)
 #endif
diff --git a/include/linux/firmware/intel/stratix10-svc-client.h b/include/linux/firmware/intel/stratix10-svc-client.h
index 520004a5f15d..532dd4bd76dd 100644
--- a/include/linux/firmware/intel/stratix10-svc-client.h
+++ b/include/linux/firmware/intel/stratix10-svc-client.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2017-2018, Intel Corporation
+ * Copyright (C) 2025, Altera Corporation
  */
 
 #ifndef __STRATIX10_SVC_CLIENT_H
@@ -290,5 +291,92 @@ int stratix10_svc_send(struct stratix10_svc_chan *chan, void *msg);
  * request process.
  */
 void stratix10_svc_done(struct stratix10_svc_chan *chan);
+
+/**
+ * typedef async_callback_t - A type definition for an asynchronous callback function.
+ *
+ * This type defines a function pointer for an asynchronous callback.
+ * The callback function takes a single argument, which is a pointer to
+ * user-defined data.
+ *
+ * @param cb_arg A pointer to user-defined data passed to the callback function.
+ */
+typedef void (*async_callback_t)(void *cb_arg);
+
+/**
+ * stratix10_svc_add_async_client - Add an asynchronous client to a Stratix 10
+ *                                  service channel.
+ * @chan: Pointer to the Stratix 10 service channel structure.
+ * @use_unique_clientid: Boolean flag indicating whether to use a unique client ID.
+ *
+ * This function registers an asynchronous client with the specified Stratix 10
+ * service channel. If the use_unique_clientid flag is set to true, a unique client
+ * ID will be assigned to the client.
+ *
+ * Return: 0 on success, or a negative error code on failure:
+ *         -EINVAL if the channel is NULL or the async controller is not initialized.
+ *         -EALREADY if the async channel is already allocated.
+ *         -ENOMEM if memory allocation fails.
+ *         Other negative values if ID allocation fails
+ */
+int stratix10_svc_add_async_client(struct stratix10_svc_chan *chan, bool use_unique_clientid);
+
+/**
+ * stratix10_svc_remove_async_client - Remove an asynchronous client from the Stratix 10
+ *                                     service channel.
+ * @chan: Pointer to the Stratix 10 service channel structure.
+ *
+ * This function removes an asynchronous client from the specified Stratix 10 service channel.
+ * It is typically used to clean up and release resources associated with the client.
+ *
+ * Return: 0 on success, -EINVAL if the channel or asynchronous channel is invalid.
+ */
+int stratix10_svc_remove_async_client(struct stratix10_svc_chan *chan);
+
+/**
+ * stratix10_svc_async_send - Send an asynchronous message to the SDM mailbox
+ *                            in EL3 secure firmware.
+ * @chan: Pointer to the service channel structure.
+ * @msg: Pointer to the message to be sent.
+ * @handler: Pointer to the handler object used by caller to track the transaction.
+ * @cb: Callback function to be called upon completion.
+ * @cb_arg: Argument to be passed to the callback function.
+ *
+ * This function sends a message asynchronously to the SDM mailbox in EL3 secure firmware.
+ * and registers a callback function to be invoked when the operation completes.
+ *
+ * Return: 0 on success,and negative error codes on failure.
+ */
+int stratix10_svc_async_send(struct stratix10_svc_chan *chan, void *msg, void **handler,
+			     async_callback_t cb, void *cb_arg);
+
+/**
+ * stratix10_svc_async_poll - Polls the status of an asynchronous service request.
+ * @chan: Pointer to the service channel structure.
+ * @tx_handle: Handle to the transaction being polled.
+ * @data: Pointer to the callback data structure to be filled with the result.
+ *
+ * This function checks the status of an asynchronous service request
+ * and fills the provided callback data structure with the result.
+ *
+ * Return: 0 on success, -EINVAL if any input parameter is invalid or if the
+ *         async controller is not initialized, -EAGAIN if the transaction is
+ *         still in progress, or other negative error codes on failure.
+ */
+int stratix10_svc_async_poll(struct stratix10_svc_chan *chan, void *tx_handle,
+			     struct stratix10_svc_cb_data *data);
+
+/**
+ * stratix10_svc_async_done - Complete an asynchronous transaction
+ * @chan: Pointer to the service channel structure
+ * @tx_handle: Pointer to the transaction handle
+ *
+ * This function completes an asynchronous transaction by removing the
+ * transaction from the hash table and deallocating the associated resources.
+ *
+ * Return: 0 on success, -EINVAL on invalid input or errors.
+ */
+int stratix10_svc_async_done(struct stratix10_svc_chan *chan, void *tx_handle);
+
 #endif