drivers/crypto/caam/qi.h

   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__ */