1 /* SPDX-License-Identifier: GPL-2.0-or-later * 1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* 2 /*
3 * Driver for Qualcomm Secure Execution Enviro 3 * Driver for Qualcomm Secure Execution Environment (SEE) interface (QSEECOM).
4 * Responsible for setting up and managing QSE 4 * Responsible for setting up and managing QSEECOM client devices.
5 * 5 *
6 * Copyright (C) 2023 Maximilian Luz <luzmaxim 6 * Copyright (C) 2023 Maximilian Luz <luzmaximilian@gmail.com>
7 */ 7 */
8 8
9 #ifndef __QCOM_QSEECOM_H 9 #ifndef __QCOM_QSEECOM_H
10 #define __QCOM_QSEECOM_H 10 #define __QCOM_QSEECOM_H
11 11
12 #include <linux/auxiliary_bus.h> 12 #include <linux/auxiliary_bus.h>
13 #include <linux/dma-mapping.h> 13 #include <linux/dma-mapping.h>
14 #include <linux/types.h> 14 #include <linux/types.h>
15 15
16 #include <linux/firmware/qcom/qcom_scm.h> 16 #include <linux/firmware/qcom/qcom_scm.h>
17 17
18 /** 18 /**
19 * struct qseecom_client - QSEECOM client devi 19 * struct qseecom_client - QSEECOM client device.
20 * @aux_dev: Underlying auxiliary device. 20 * @aux_dev: Underlying auxiliary device.
21 * @app_id: ID of the loaded application. 21 * @app_id: ID of the loaded application.
22 */ 22 */
23 struct qseecom_client { 23 struct qseecom_client {
24 struct auxiliary_device aux_dev; 24 struct auxiliary_device aux_dev;
25 u32 app_id; 25 u32 app_id;
26 }; 26 };
27 27
28 /** 28 /**
>> 29 * qseecom_scm_dev() - Get the SCM device associated with the QSEECOM client.
>> 30 * @client: The QSEECOM client device.
>> 31 *
>> 32 * Returns the SCM device under which the provided QSEECOM client device
>> 33 * operates. This function is intended to be used for DMA allocations.
>> 34 */
>> 35 static inline struct device *qseecom_scm_dev(struct qseecom_client *client)
>> 36 {
>> 37 return client->aux_dev.dev.parent->parent;
>> 38 }
>> 39
>> 40 /**
>> 41 * qseecom_dma_alloc() - Allocate DMA memory for a QSEECOM client.
>> 42 * @client: The QSEECOM client to allocate the memory for.
>> 43 * @size: The number of bytes to allocate.
>> 44 * @dma_handle: Pointer to where the DMA address should be stored.
>> 45 * @gfp: Allocation flags.
>> 46 *
>> 47 * Wrapper function for dma_alloc_coherent(), allocating DMA memory usable for
>> 48 * TZ/QSEECOM communication. Refer to dma_alloc_coherent() for details.
>> 49 */
>> 50 static inline void *qseecom_dma_alloc(struct qseecom_client *client, size_t size,
>> 51 dma_addr_t *dma_handle, gfp_t gfp)
>> 52 {
>> 53 return dma_alloc_coherent(qseecom_scm_dev(client), size, dma_handle, gfp);
>> 54 }
>> 55
>> 56 /**
>> 57 * dma_free_coherent() - Free QSEECOM DMA memory.
>> 58 * @client: The QSEECOM client for which the memory has been allocated.
>> 59 * @size: The number of bytes allocated.
>> 60 * @cpu_addr: Virtual memory address to free.
>> 61 * @dma_handle: DMA memory address to free.
>> 62 *
>> 63 * Wrapper function for dma_free_coherent(), freeing memory previously
>> 64 * allocated with qseecom_dma_alloc(). Refer to dma_free_coherent() for
>> 65 * details.
>> 66 */
>> 67 static inline void qseecom_dma_free(struct qseecom_client *client, size_t size,
>> 68 void *cpu_addr, dma_addr_t dma_handle)
>> 69 {
>> 70 return dma_free_coherent(qseecom_scm_dev(client), size, cpu_addr, dma_handle);
>> 71 }
>> 72
>> 73 /**
29 * qcom_qseecom_app_send() - Send to and recei 74 * qcom_qseecom_app_send() - Send to and receive data from a given QSEE app.
30 * @client: The QSEECOM client associated wi 75 * @client: The QSEECOM client associated with the target app.
31 * @req: Request buffer sent to the app ( !! 76 * @req: DMA address of the request buffer sent to the app.
32 * @req_size: Size of the request buffer. 77 * @req_size: Size of the request buffer.
33 * @rsp: Response buffer, written to by t !! 78 * @rsp: DMA address of the response buffer, written to by the app.
34 * @rsp_size: Size of the response buffer. 79 * @rsp_size: Size of the response buffer.
35 * 80 *
36 * Sends a request to the QSEE app associated 81 * Sends a request to the QSEE app associated with the given client and read
37 * back its response. The caller must provide 82 * back its response. The caller must provide two DMA memory regions, one for
38 * the request and one for the response, and f 83 * the request and one for the response, and fill out the @req region with the
39 * respective (app-specific) request data. The 84 * respective (app-specific) request data. The QSEE app reads this and returns
40 * its response in the @rsp region. 85 * its response in the @rsp region.
41 * 86 *
42 * Note: This is a convenience wrapper around 87 * Note: This is a convenience wrapper around qcom_scm_qseecom_app_send().
43 * Clients should prefer to use this wrapper. 88 * Clients should prefer to use this wrapper.
44 * 89 *
45 * Return: Zero on success, nonzero on failure 90 * Return: Zero on success, nonzero on failure.
46 */ 91 */
47 static inline int qcom_qseecom_app_send(struct 92 static inline int qcom_qseecom_app_send(struct qseecom_client *client,
48 void * !! 93 dma_addr_t req, size_t req_size,
49 void * !! 94 dma_addr_t rsp, size_t rsp_size)
50 { 95 {
51 return qcom_scm_qseecom_app_send(clien 96 return qcom_scm_qseecom_app_send(client->app_id, req, req_size, rsp, rsp_size);
52 } 97 }
53 98
54 #endif /* __QCOM_QSEECOM_H */ 99 #endif /* __QCOM_QSEECOM_H */
55 100
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