crypto/caam/qi.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * Public definitions for the CAAM/QI (Queue Interface) backend.
0004  *
0005  * Copyright 2013-2016 Freescale Semiconductor, Inc.
0006  * Copyright 2016-2017, 2020 NXP
0007  */
0008
0009 #ifndef __QI_H__
0010 #define __QI_H__
0011
0012 #include <soc/fsl/qman.h>
0013 #include "compat.h"
0014 #include "desc.h"
0015 #include "desc_constr.h"
0016
0017 /* Length of a single buffer in the QI driver memory cache */
0018 #define CAAM_QI_MEMCACHE_SIZE   768
0019
0020 extern bool caam_congested __read_mostly;
0021
0022 /*
0023  * This is the request structure the driver application should fill while
0024  * submitting a job to driver.
0025  */
0026 struct caam_drv_req;
0027
0028 /*
0029  * caam_qi_cbk - application's callback function invoked by the driver when the
0030  *               request has been successfully processed.
0031  * @drv_req: original request that was submitted
0032  * @status: completion status of request (0 - success, non-zero - error code)
0033  */
0034 typedef void (*caam_qi_cbk)(struct caam_drv_req *drv_req, u32 status);
0035
0036 enum optype {
0037     ENCRYPT,
0038     DECRYPT,
0039     NUM_OP
0040 };
0041
0042 /**
0043  * caam_drv_ctx - CAAM/QI backend driver context
0044  *
0045  * The jobs are processed by the driver against a driver context.
0046  * With every cryptographic context, a driver context is attached.
0047  * The driver context contains data for private use by driver.
0048  * For the applications, this is an opaque structure.
0049  *
0050  * @prehdr: preheader placed before shrd desc
0051  * @sh_desc: shared descriptor
0052  * @context_a: shared descriptor dma address
0053  * @req_fq: to-CAAM request frame queue
0054  * @rsp_fq: from-CAAM response frame queue
0055  * @refcnt: reference counter incremented for each frame enqueued in to-CAAM FQ
0056  * @cpu: cpu on which to receive CAAM response
0057  * @op_type: operation type
0058  * @qidev: device pointer for CAAM/QI backend
0059  */
0060 struct caam_drv_ctx {
0061     u32 prehdr[2];
0062     u32 sh_desc[MAX_SDLEN];
0063     dma_addr_t context_a;
0064     struct qman_fq *req_fq;
0065     struct qman_fq *rsp_fq;
0066     refcount_t refcnt;
0067     int cpu;
0068     enum optype op_type;
0069     struct device *qidev;
0070 } ____cacheline_aligned;
0071
0072 /**
0073  * caam_drv_req - The request structure the driver application should fill while
0074  *                submitting a job to driver.
0075  * @fd_sgt: QMan S/G pointing to output (fd_sgt[0]) and input (fd_sgt[1])
0076  *          buffers.
0077  * @cbk: callback function to invoke when job is completed
0078  * @app_ctx: arbitrary context attached with request by the application
0079  *
0080  * The fields mentioned below should not be used by application.
0081  * These are for private use by driver.
0082  *
0083  * @hdr__: linked list header to maintain list of outstanding requests to CAAM
0084  * @hwaddr: DMA address for the S/G table.
0085  */
0086 struct caam_drv_req {
0087     struct qm_sg_entry fd_sgt[2];
0088     struct caam_drv_ctx *drv_ctx;
0089     caam_qi_cbk cbk;
0090     void *app_ctx;
0091 } ____cacheline_aligned;
0092
0093 /**
0094  * caam_drv_ctx_init - Initialise a CAAM/QI driver context
0095  *
0096  * A CAAM/QI driver context must be attached with each cryptographic context.
0097  * This function allocates memory for CAAM/QI context and returns a handle to
0098  * the application. This handle must be submitted along with each enqueue
0099  * request to the driver by the application.
0100  *
0101  * @cpu: CPU where the application prefers to the driver to receive CAAM
0102  *       responses. The request completion callback would be issued from this
0103  *       CPU.
0104  * @sh_desc: shared descriptor pointer to be attached with CAAM/QI driver
0105  *           context.
0106  *
0107  * Returns a driver context on success or negative error code on failure.
0108  */
0109 struct caam_drv_ctx *caam_drv_ctx_init(struct device *qidev, int *cpu,
0110                        u32 *sh_desc);
0111
0112 /**
0113  * caam_qi_enqueue - Submit a request to QI backend driver.
0114  *
0115  * The request structure must be properly filled as described above.
0116  *
0117  * @qidev: device pointer for QI backend
0118  * @req: CAAM QI request structure
0119  *
0120  * Returns 0 on success or negative error code on failure.
0121  */
0122 int caam_qi_enqueue(struct device *qidev, struct caam_drv_req *req);
0123
0124 /**
0125  * caam_drv_ctx_busy - Check if there are too many jobs pending with CAAM
0126  *             or too many CAAM responses are pending to be processed.
0127  * @drv_ctx: driver context for which job is to be submitted
0128  *
0129  * Returns caam congestion status 'true/false'
0130  */
0131 bool caam_drv_ctx_busy(struct caam_drv_ctx *drv_ctx);
0132
0133 /**
0134  * caam_drv_ctx_update - Update QI driver context
0135  *
0136  * Invoked when shared descriptor is required to be change in driver context.
0137  *
0138  * @drv_ctx: driver context to be updated
0139  * @sh_desc: new shared descriptor pointer to be updated in QI driver context
0140  *
0141  * Returns 0 on success or negative error code on failure.
0142  */
0143 int caam_drv_ctx_update(struct caam_drv_ctx *drv_ctx, u32 *sh_desc);
0144
0145 /**
0146  * caam_drv_ctx_rel - Release a QI driver context
0147  * @drv_ctx: context to be released
0148  */
0149 void caam_drv_ctx_rel(struct caam_drv_ctx *drv_ctx);
0150
0151 int caam_qi_init(struct platform_device *pdev);
0152
0153 /**
0154  * qi_cache_alloc - Allocate buffers from CAAM-QI cache
0155  *
0156  * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) needs data which has
0157  * to be allocated on the hotpath. Instead of using malloc, one can use the
0158  * services of the CAAM QI memory cache (backed by kmem_cache). The buffers
0159  * will have a size of 256B, which is sufficient for hosting 16 SG entries.
0160  *
0161  * @flags: flags that would be used for the equivalent malloc(..) call
0162  *
0163  * Returns a pointer to a retrieved buffer on success or NULL on failure.
0164  */
0165 void *qi_cache_alloc(gfp_t flags);
0166
0167 /**
0168  * qi_cache_free - Frees buffers allocated from CAAM-QI cache
0169  *
0170  * Invoked when a user of the CAAM-QI (i.e. caamalg-qi) no longer needs
0171  * the buffer previously allocated by a qi_cache_alloc call.
0172  * No checking is being done, the call is a passthrough call to
0173  * kmem_cache_free(...)
0174  *
0175  * @obj: object previously allocated using qi_cache_alloc()
0176  */
0177 void qi_cache_free(void *obj);
0178
0179 #endif /* __QI_H__ */