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 NXP 7 */ 8 9 #ifndef __QI_H__ 10 #define __QI_H__ 11 12 #include <soc/fsl/qman.h> 13 #include "compat.h" 14 #include "desc.h" 15 #include "desc_constr.h" 16 17 /* 18 * CAAM hardware constructs a job descriptor which points to a shared descriptor 19 * (as pointed by context_a of to-CAAM FQ). 20 * When the job descriptor is executed by DECO, the whole job descriptor 21 * together with shared descriptor gets loaded in DECO buffer, which is 22 * 64 words (each 32-bit) long. 23 * 24 * The job descriptor constructed by CAAM hardware has the following layout: 25 * 26 * HEADER (1 word) 27 * Shdesc ptr (1 or 2 words) 28 * SEQ_OUT_PTR (1 word) 29 * Out ptr (1 or 2 words) 30 * Out length (1 word) 31 * SEQ_IN_PTR (1 word) 32 * In ptr (1 or 2 words) 33 * In length (1 word) 34 * 35 * The shdesc ptr is used to fetch shared descriptor contents into DECO buffer. 36 * 37 * Apart from shdesc contents, the total number of words that get loaded in DECO 38 * buffer are '8' or '11'. The remaining words in DECO buffer can be used for 39 * storing shared descriptor. 40 */ 41 #define MAX_SDLEN ((CAAM_DESC_BYTES_MAX - DESC_JOB_IO_LEN) / CAAM_CMD_SZ) 42 43 /* Length of a single buffer in the QI driver memory cache */ 44 #define CAAM_QI_MEMCACHE_SIZE 768 45 46 extern bool caam_congested __read_mostly; 47 48 /* 49 * This is the request structure the driver application should fill while 50 * submitting a job to driver. 51 */ 52 struct caam_drv_req; 53 54 /* 55 * caam_qi_cbk - application's callback function invoked by the driver when the 56 * request has been successfully processed. 57 * @drv_req: original request that was submitted 58 * @status: completion status of request (0 - success, non-zero - error code) 59 */ 60 typedef void (*caam_qi_cbk)(struct caam_drv_req *drv_req, u32 status); 61 62 enum optype { 63 ENCRYPT, 64 DECRYPT, 65 NUM_OP 66 }; 67 68 /** 69 * caam_drv_ctx - CAAM/QI backend driver context 70 * 71 * The jobs are processed by the driver against a driver context. 72 * With every cryptographic context, a driver context is attached. 73 * The driver context contains data for private use by driver. 74 * For the applications, this is an opaque structure. 75 * 76 * @prehdr: preheader placed before shrd desc 77 * @sh_desc: shared descriptor 78 * @context_a: shared descriptor dma address 79 * @req_fq: to-CAAM request frame queue 80 * @rsp_fq: from-CAAM response frame queue 81 * @cpu: cpu on which to receive CAAM response 82 * @op_type: operation type 83 * @qidev: device pointer for CAAM/QI backend 84 */ 85 struct caam_drv_ctx { 86 u32 prehdr[2]; 87 u32 sh_desc[MAX_SDLEN]; 88 dma_addr_t context_a; 89 struct qman_fq *req_fq; 90 struct qman_fq *rsp_fq; 91 int cpu; 92 enum optype op_type; 93 struct device *qidev; 94 } ____cacheline_aligned; 95 96 /** 97 * caam_drv_req - The request structure the driver application should fill while 98 * submitting a job to driver. 99 * @fd_sgt: QMan S/G pointing to output (fd_sgt[0]) and input (fd_sgt[1]) 100 * buffers. 101 * @cbk: callback function to invoke when job is completed 102 * @app_ctx: arbitrary context attached with request by the application 103 * 104 * The fields mentioned below should not be used by application. 105 * These are for private use by driver. 106 * 107 * @hdr__: linked list header to maintain list of outstanding requests to CAAM 108 * @hwaddr: DMA address for the S/G table. 109 */ 110 struct caam_drv_req { 111 struct qm_sg_entry fd_sgt[2]; 112 struct caam_drv_ctx *drv_ctx; 113 caam_qi_cbk cbk; 114 void *app_ctx; 115 } ____cacheline_aligned; 116 117 /** 118 * caam_drv_ctx_init - Initialise a CAAM/QI driver context 119 * 120 * A CAAM/QI driver context must be attached with each cryptographic context. 121 * This function allocates memory for CAAM/QI context and returns a handle to 122 * the application. This handle must be submitted along with each enqueue 123 * request to the driver by the application. 124 * 125 * @cpu: CPU where the application prefers to the driver to receive CAAM 126 * responses. The request completion callback would be issued from this 127 * CPU. 128 * @sh_desc: shared descriptor pointer to be attached with CAAM/QI driver 129 * context. 130 * 131 * Returns a driver context on success or negative error code on failure. 132 */ 133 struct caam_drv_ctx *caam_drv_ctx_init(struct device *qidev, int *cpu, 134 u32 *sh_desc); 135 136 /** 137 * caam_qi_enqueue - Submit a request to QI backend driver. 138 * 139 * The request structure must be properly filled as described above. 140 * 141 * @qidev: device pointer for QI backend 142 * @req: CAAM QI request structure 143 * 144 * Returns 0 on success or negative error code on failure. 145 */ 146 int caam_qi_enqueue(struct device *qidev, struct caam_drv_req *req); 147 148 /** 149 * caam_drv_ctx_busy - Check if there are too many jobs pending with CAAM 150 * or too many CAAM responses are pending to be processed. 151 * @drv_ctx: driver context for which job is to be submitted 152 * 153 * Returns caam congestion status 'true/false' 154 */ 155 bool caam_drv_ctx_busy(struct caam_drv_ctx *drv_ctx); 156 157 /** 158 * caam_drv_ctx_update - Update QI driver context 159 * 160 * Invoked when shared descriptor is required to be change in driver context. 161 * 162 * @drv_ctx: driver context to be updated 163 * @sh_desc: new shared descriptor pointer to be updated in QI driver context 164 * 165 * Returns 0 on success or negative error code on failure. 166 */ 167 int caam_drv_ctx_update(struct caam_drv_ctx *drv_ctx, u32 *sh_desc); 168 169 /** 170 * caam_drv_ctx_rel - Release a QI driver context 171 * @drv_ctx: context to be released 172 */ 173 void caam_drv_ctx_rel(struct caam_drv_ctx *drv_ctx); 174 175 int caam_qi_init(struct platform_device *pdev); 176 void caam_qi_shutdown(struct device *dev); 177 178 /** 179 * qi_cache_alloc - Allocate buffers from CAAM-QI cache 180 * 181 * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) needs data which has 182 * to be allocated on the hotpath. Instead of using malloc, one can use the 183 * services of the CAAM QI memory cache (backed by kmem_cache). The buffers 184 * will have a size of 256B, which is sufficient for hosting 16 SG entries. 185 * 186 * @flags: flags that would be used for the equivalent malloc(..) call 187 * 188 * Returns a pointer to a retrieved buffer on success or NULL on failure. 189 */ 190 void *qi_cache_alloc(gfp_t flags); 191 192 /** 193 * qi_cache_free - Frees buffers allocated from CAAM-QI cache 194 * 195 * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) no longer needs 196 * the buffer previously allocated by a qi_cache_alloc call. 197 * No checking is being done, the call is a passthrough call to 198 * kmem_cache_free(...) 199 * 200 * @obj: object previously allocated using qi_cache_alloc() 201 */ 202 void qi_cache_free(void *obj); 203 204 #endif /* __QI_H__ */ 205