1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Public definitions for the CAAM/QI (Queue Interface) backend. 4 * 5 * Copyright 2013-2016 Freescale Semiconductor, Inc. 6 * Copyright 2016-2017, 2020 NXP 7 */ 8 9 #ifndef __QI_H__ 10 #define __QI_H__ 11 12 #include <crypto/algapi.h> 13 #include <linux/compiler_attributes.h> 14 #include <soc/fsl/qman.h> 15 #include "compat.h" 16 #include "desc.h" 17 #include "desc_constr.h" 18 19 /* Length of a single buffer in the QI driver memory cache */ 20 #define CAAM_QI_MEMCACHE_SIZE 768 21 22 extern bool caam_congested __read_mostly; 23 24 /* 25 * This is the request structure the driver application should fill while 26 * submitting a job to driver. 27 */ 28 struct caam_drv_req; 29 30 /* 31 * caam_qi_cbk - application's callback function invoked by the driver when the 32 * request has been successfully processed. 33 * @drv_req: original request that was submitted 34 * @status: completion status of request (0 - success, non-zero - error code) 35 */ 36 typedef void (*caam_qi_cbk)(struct caam_drv_req *drv_req, u32 status); 37 38 enum optype { 39 ENCRYPT, 40 DECRYPT, 41 NUM_OP 42 }; 43 44 /** 45 * caam_drv_ctx - CAAM/QI backend driver context 46 * 47 * The jobs are processed by the driver against a driver context. 48 * With every cryptographic context, a driver context is attached. 49 * The driver context contains data for private use by driver. 50 * For the applications, this is an opaque structure. 51 * 52 * @prehdr: preheader placed before shrd desc 53 * @sh_desc: shared descriptor 54 * @context_a: shared descriptor dma address 55 * @req_fq: to-CAAM request frame queue 56 * @rsp_fq: from-CAAM response frame queue 57 * @refcnt: reference counter incremented for each frame enqueued in to-CAAM FQ 58 * @cpu: cpu on which to receive CAAM response 59 * @op_type: operation type 60 * @qidev: device pointer for CAAM/QI backend 61 */ 62 struct caam_drv_ctx { 63 struct { 64 u32 prehdr[2]; 65 u32 sh_desc[MAX_SDLEN]; 66 } __aligned(CRYPTO_DMA_ALIGN); 67 dma_addr_t context_a; 68 struct qman_fq *req_fq; 69 struct qman_fq *rsp_fq; 70 refcount_t refcnt; 71 int cpu; 72 enum optype op_type; 73 struct device *qidev; 74 }; 75 76 /** 77 * caam_drv_req - The request structure the driver application should fill while 78 * submitting a job to driver. 79 * @fd_sgt: QMan S/G pointing to output (fd_sgt[0]) and input (fd_sgt[1]) 80 * buffers. 81 * @cbk: callback function to invoke when job is completed 82 * @app_ctx: arbitrary context attached with request by the application 83 * 84 * The fields mentioned below should not be used by application. 85 * These are for private use by driver. 86 * 87 * @hdr__: linked list header to maintain list of outstanding requests to CAAM 88 * @hwaddr: DMA address for the S/G table. 89 */ 90 struct caam_drv_req { 91 struct qm_sg_entry fd_sgt[2]; 92 struct caam_drv_ctx *drv_ctx; 93 caam_qi_cbk cbk; 94 void *app_ctx; 95 } __aligned(CRYPTO_DMA_ALIGN); 96 97 /** 98 * caam_drv_ctx_init - Initialise a CAAM/QI driver context 99 * 100 * A CAAM/QI driver context must be attached with each cryptographic context. 101 * This function allocates memory for CAAM/QI context and returns a handle to 102 * the application. This handle must be submitted along with each enqueue 103 * request to the driver by the application. 104 * 105 * @cpu: CPU where the application prefers to the driver to receive CAAM 106 * responses. The request completion callback would be issued from this 107 * CPU. 108 * @sh_desc: shared descriptor pointer to be attached with CAAM/QI driver 109 * context. 110 * 111 * Returns a driver context on success or negative error code on failure. 112 */ 113 struct caam_drv_ctx *caam_drv_ctx_init(struct device *qidev, int *cpu, 114 u32 *sh_desc); 115 116 /** 117 * caam_qi_enqueue - Submit a request to QI backend driver. 118 * 119 * The request structure must be properly filled as described above. 120 * 121 * @qidev: device pointer for QI backend 122 * @req: CAAM QI request structure 123 * 124 * Returns 0 on success or negative error code on failure. 125 */ 126 int caam_qi_enqueue(struct device *qidev, struct caam_drv_req *req); 127 128 /** 129 * caam_drv_ctx_busy - Check if there are too many jobs pending with CAAM 130 * or too many CAAM responses are pending to be processed. 131 * @drv_ctx: driver context for which job is to be submitted 132 * 133 * Returns caam congestion status 'true/false' 134 */ 135 bool caam_drv_ctx_busy(struct caam_drv_ctx *drv_ctx); 136 137 /** 138 * caam_drv_ctx_update - Update QI driver context 139 * 140 * Invoked when shared descriptor is required to be change in driver context. 141 * 142 * @drv_ctx: driver context to be updated 143 * @sh_desc: new shared descriptor pointer to be updated in QI driver context 144 * 145 * Returns 0 on success or negative error code on failure. 146 */ 147 int caam_drv_ctx_update(struct caam_drv_ctx *drv_ctx, u32 *sh_desc); 148 149 /** 150 * caam_drv_ctx_rel - Release a QI driver context 151 * @drv_ctx: context to be released 152 */ 153 void caam_drv_ctx_rel(struct caam_drv_ctx *drv_ctx); 154 155 int caam_qi_init(struct platform_device *pdev); 156 157 /** 158 * qi_cache_alloc - Allocate buffers from CAAM-QI cache 159 * 160 * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) needs data which has 161 * to be allocated on the hotpath. Instead of using malloc, one can use the 162 * services of the CAAM QI memory cache (backed by kmem_cache). The buffers 163 * will have a size of 256B, which is sufficient for hosting 16 SG entries. 164 * 165 * @flags: flags that would be used for the equivalent malloc(..) call 166 * 167 * Returns a pointer to a retrieved buffer on success or NULL on failure. 168 */ 169 void *qi_cache_alloc(gfp_t flags); 170 171 /** 172 * qi_cache_free - Frees buffers allocated from CAAM-QI cache 173 * 174 * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) no longer needs 175 * the buffer previously allocated by a qi_cache_alloc call. 176 * No checking is being done, the call is a passthrough call to 177 * kmem_cache_free(...) 178 * 179 * @obj: object previously allocated using qi_cache_alloc() 180 */ 181 void qi_cache_free(void *obj); 182 183 #endif /* __QI_H__ */ 184