// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2020 Marvell. */

#include "otx2_cptvf.h"
#include "otx2_cpt_common.h"

/* Default timeout when waiting for free pending entry in us */
#define CPT_PENTRY_TIMEOUT      1000
#define CPT_PENTRY_STEP         50

/* Default threshold for stopping and resuming sender requests */
#define CPT_IQ_STOP_MARGIN      128
#define CPT_IQ_RESUME_MARGIN    512

/* Default command timeout in seconds */
#define CPT_COMMAND_TIMEOUT     4
#define CPT_TIME_IN_RESET_COUNT 5

static void otx2_cpt_dump_sg_list(struct pci_dev *pdev,
                                  struct otx2_cpt_req_info *req)
{
        int i;

        pr_debug("Gather list size %d\n", req->in_cnt);
        for (i = 0; i < req->in_cnt; i++) {
                pr_debug("Buffer %d size %d, vptr 0x%p, dmaptr 0x%llx\n", i,
                         req->in[i].size, req->in[i].vptr,
                         req->in[i].dma_addr);
                pr_debug("Buffer hexdump (%d bytes)\n",
                         req->in[i].size);
                print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1,
                                     req->in[i].vptr, req->in[i].size, false);
        }
        pr_debug("Scatter list size %d\n", req->out_cnt);
        for (i = 0; i < req->out_cnt; i++) {
                pr_debug("Buffer %d size %d, vptr 0x%p, dmaptr 0x%llx\n", i,
                         req->out[i].size, req->out[i].vptr,
                         req->out[i].dma_addr);
                pr_debug("Buffer hexdump (%d bytes)\n", req->out[i].size);
                print_hex_dump_debug("", DUMP_PREFIX_NONE, 16, 1,
                                     req->out[i].vptr, req->out[i].size, false);
        }
}

static inline struct otx2_cpt_pending_entry *get_free_pending_entry(
                                        struct otx2_cpt_pending_queue *q,
                                        int qlen)
{
        struct otx2_cpt_pending_entry *ent = NULL;

        ent = &q->head[q->rear];
        if (unlikely(ent->busy))
                return NULL;

        q->rear++;
        if (unlikely(q->rear == qlen))
                q->rear = 0;

        return ent;
}

static inline u32 modulo_inc(u32 index, u32 length, u32 inc)
{
        if (WARN_ON(inc > length))
                inc = length;

        index += inc;
        if (unlikely(index >= length))
                index -= length;

        return index;
}

static inline void free_pentry(struct otx2_cpt_pending_entry *pentry)
{
        pentry->completion_addr = NULL;
        pentry->info = NULL;
        pentry->callback = NULL;
        pentry->areq = NULL;
        pentry->resume_sender = false;
        pentry->busy = false;
}

static int process_request(struct pci_dev *pdev, struct otx2_cpt_req_info *req,
                           struct otx2_cpt_pending_queue *pqueue,
                           struct otx2_cptlf_info *lf)
{
        struct otx2_cptvf_request *cpt_req = &req->req;
        struct otx2_cpt_pending_entry *pentry = NULL;
        union otx2_cpt_ctrl_info *ctrl = &req->ctrl;
        struct otx2_cpt_inst_info *info = NULL;
        union otx2_cpt_res_s *result = NULL;
        struct otx2_cpt_iq_command iq_cmd;
        union otx2_cpt_inst_s cptinst;
        int retry, ret = 0;
        u8 resume_sender;
        gfp_t gfp;

        gfp = (req->areq->flags & CRYPTO_TFM_REQ_MAY_SLEEP) ? GFP_KERNEL :
                                                              GFP_ATOMIC;
        if (unlikely(!otx2_cptlf_started(lf->lfs)))
                return -ENODEV;

        info = lf->lfs->ops->cpt_sg_info_create(pdev, req, gfp);
        if (unlikely(!info)) {
                dev_err(&pdev->dev, "Setting up cpt inst info failed");
                return -ENOMEM;
        }
        cpt_req->dlen = info->dlen;

        result = info->completion_addr;
        result->s.compcode = OTX2_CPT_COMPLETION_CODE_INIT;

        spin_lock_bh(&pqueue->lock);
        pentry = get_free_pending_entry(pqueue, pqueue->qlen);
        retry = CPT_PENTRY_TIMEOUT / CPT_PENTRY_STEP;
        while (unlikely(!pentry) && retry--) {
                spin_unlock_bh(&pqueue->lock);
                udelay(CPT_PENTRY_STEP);
                spin_lock_bh(&pqueue->lock);
                pentry = get_free_pending_entry(pqueue, pqueue->qlen);
        }

        if (unlikely(!pentry)) {
                ret = -ENOSPC;
                goto destroy_info;
        }

        /*
         * Check if we are close to filling in entire pending queue,
         * if so then tell the sender to stop/sleep by returning -EBUSY
         * We do it only for context which can sleep (GFP_KERNEL)
         */
        if (gfp == GFP_KERNEL &&
            pqueue->pending_count > (pqueue->qlen - CPT_IQ_STOP_MARGIN)) {
                pentry->resume_sender = true;
        } else
                pentry->resume_sender = false;
        resume_sender = pentry->resume_sender;
        pqueue->pending_count++;

        pentry->completion_addr = info->completion_addr;
        pentry->info = info;
        pentry->callback = req->callback;
        pentry->areq = req->areq;
        pentry->busy = true;
        info->pentry = pentry;
        info->time_in = jiffies;
        info->req = req;

        /* Fill in the command */
        iq_cmd.cmd.u = 0;
        iq_cmd.cmd.s.opcode = cpu_to_be16(cpt_req->opcode.flags);
        iq_cmd.cmd.s.param1 = cpu_to_be16(cpt_req->param1);
        iq_cmd.cmd.s.param2 = cpu_to_be16(cpt_req->param2);
        iq_cmd.cmd.s.dlen   = cpu_to_be16(cpt_req->dlen);

        /* 64-bit swap for microcode data reads, not needed for addresses*/
        cpu_to_be64s(&iq_cmd.cmd.u);
        iq_cmd.dptr = info->dptr_baddr | info->gthr_sz << 60;
        iq_cmd.rptr = info->rptr_baddr | info->sctr_sz << 60;
        iq_cmd.cptr.s.cptr = cpt_req->cptr_dma;
        iq_cmd.cptr.s.grp = ctrl->s.grp;

        /* Fill in the CPT_INST_S type command for HW interpretation */
        otx2_cpt_fill_inst(&cptinst, &iq_cmd, info->comp_baddr);

        /* Print debug info if enabled */
        otx2_cpt_dump_sg_list(pdev, req);
        pr_debug("Cpt_inst_s hexdump (%d bytes)\n", OTX2_CPT_INST_SIZE);
        print_hex_dump_debug("", 0, 16, 1, &cptinst, OTX2_CPT_INST_SIZE, false);
        pr_debug("Dptr hexdump (%d bytes)\n", cpt_req->dlen);
        print_hex_dump_debug("", 0, 16, 1, info->in_buffer,
                             cpt_req->dlen, false);

        /* Send CPT command */
        lf->lfs->ops->send_cmd(&cptinst, 1, lf);

        /*
         * We allocate and prepare pending queue entry in critical section
         * together with submitting CPT instruction to CPT instruction queue
         * to make sure that order of CPT requests is the same in both
         * pending and instruction queues
         */
        spin_unlock_bh(&pqueue->lock);

        ret = resume_sender ? -EBUSY : -EINPROGRESS;
        return ret;

destroy_info:
        spin_unlock_bh(&pqueue->lock);
        otx2_cpt_info_destroy(pdev, info);
        return ret;
}

int otx2_cpt_do_request(struct pci_dev *pdev, struct otx2_cpt_req_info *req,
                        int cpu_num)
{
        struct otx2_cptvf_dev *cptvf = pci_get_drvdata(pdev);
        struct otx2_cptlfs_info *lfs = &cptvf->lfs;

        return process_request(lfs->pdev, req, &lfs->lf[cpu_num].pqueue,
                               &lfs->lf[cpu_num]);
}

static int cpt_process_ccode(struct otx2_cptlfs_info *lfs,
                             union otx2_cpt_res_s *cpt_status,
                             struct otx2_cpt_inst_info *info,
                             u32 *res_code)
{
        u8 uc_ccode = lfs->ops->cpt_get_uc_compcode(cpt_status);
        u8 ccode = lfs->ops->cpt_get_compcode(cpt_status);
        struct pci_dev *pdev = lfs->pdev;

        switch (ccode) {
        case OTX2_CPT_COMP_E_FAULT:
                dev_err(&pdev->dev,
                        "Request failed with DMA fault\n");
                otx2_cpt_dump_sg_list(pdev, info->req);
                break;

        case OTX2_CPT_COMP_E_HWERR:
                dev_err(&pdev->dev,
                        "Request failed with hardware error\n");
                otx2_cpt_dump_sg_list(pdev, info->req);
                break;

        case OTX2_CPT_COMP_E_INSTERR:
                dev_err(&pdev->dev,
                        "Request failed with instruction error\n");
                otx2_cpt_dump_sg_list(pdev, info->req);
                break;

        case OTX2_CPT_COMP_E_NOTDONE:
                /* check for timeout */
                if (time_after_eq(jiffies, info->time_in +
                                  CPT_COMMAND_TIMEOUT * HZ))
                        dev_warn(&pdev->dev,
                                 "Request timed out 0x%p", info->req);
                else if (info->extra_time < CPT_TIME_IN_RESET_COUNT) {
                        info->time_in = jiffies;
                        info->extra_time++;
                }
                return 1;

        case OTX2_CPT_COMP_E_GOOD:
        case OTX2_CPT_COMP_E_WARN:
                /*
                 * Check microcode completion code, it is only valid
                 * when completion code is CPT_COMP_E::GOOD
                 */
                if (uc_ccode != OTX2_CPT_UCC_SUCCESS) {
                        /*
                         * If requested hmac is truncated and ucode returns
                         * s/g write length error then we report success
                         * because ucode writes as many bytes of calculated
                         * hmac as available in gather buffer and reports
                         * s/g write length error if number of bytes in gather
                         * buffer is less than full hmac size.
                         */
                        if (info->req->is_trunc_hmac &&
                            uc_ccode == OTX2_CPT_UCC_SG_WRITE_LENGTH) {
                                *res_code = 0;
                                break;
                        }

                        pr_debug("Request failed with software error code 0x%x: algo = %s driver = %s\n",
                                 cpt_status->s.uc_compcode,
                                 info->req->areq->tfm->__crt_alg->cra_name,
                                 info->req->areq->tfm->__crt_alg->cra_driver_name);
                        otx2_cpt_dump_sg_list(pdev, info->req);
                        break;
                }
                /* Request has been processed with success */
                *res_code = 0;
                break;

        default:
                dev_err(&pdev->dev,
                        "Request returned invalid status %d\n", ccode);
                break;
        }
        return 0;
}

static inline void process_pending_queue(struct otx2_cptlfs_info *lfs,
                                         struct otx2_cpt_pending_queue *pqueue)
{
        struct otx2_cpt_pending_entry *resume_pentry = NULL;
        void (*callback)(int status, void *arg, void *req);
        struct otx2_cpt_pending_entry *pentry = NULL;
        union otx2_cpt_res_s *cpt_status = NULL;
        struct otx2_cpt_inst_info *info = NULL;
        struct otx2_cpt_req_info *req = NULL;
        struct crypto_async_request *areq;
        struct pci_dev *pdev = lfs->pdev;
        u32 res_code, resume_index;

        while (1) {
                spin_lock_bh(&pqueue->lock);
                pentry = &pqueue->head[pqueue->front];

                if (WARN_ON(!pentry)) {
                        spin_unlock_bh(&pqueue->lock);
                        break;
                }

                res_code = -EINVAL;
                if (unlikely(!pentry->busy)) {
                        spin_unlock_bh(&pqueue->lock);
                        break;
                }

                if (unlikely(!pentry->callback)) {
                        dev_err(&pdev->dev, "Callback NULL\n");
                        goto process_pentry;
                }

                info = pentry->info;
                if (unlikely(!info)) {
                        dev_err(&pdev->dev, "Pending entry post arg NULL\n");
                        goto process_pentry;
                }

                req = info->req;
                if (unlikely(!req)) {
                        dev_err(&pdev->dev, "Request NULL\n");
                        goto process_pentry;
                }

                cpt_status = pentry->completion_addr;
                if (unlikely(!cpt_status)) {
                        dev_err(&pdev->dev, "Completion address NULL\n");
                        goto process_pentry;
                }

                if (cpt_process_ccode(lfs, cpt_status, info, &res_code)) {
                        spin_unlock_bh(&pqueue->lock);
                        return;
                }
                info->pdev = pdev;

process_pentry:
                /*
                 * Check if we should inform sending side to resume
                 * We do it CPT_IQ_RESUME_MARGIN elements in advance before
                 * pending queue becomes empty
                 */
                resume_index = modulo_inc(pqueue->front, pqueue->qlen,
                                          CPT_IQ_RESUME_MARGIN);
                resume_pentry = &pqueue->head[resume_index];
                if (resume_pentry &&
                    resume_pentry->resume_sender) {
                        resume_pentry->resume_sender = false;
                        callback = resume_pentry->callback;
                        areq = resume_pentry->areq;

                        if (callback) {
                                spin_unlock_bh(&pqueue->lock);

                                /*
                                 * EINPROGRESS is an indication for sending
                                 * side that it can resume sending requests
                                 */
                                callback(-EINPROGRESS, areq, info);
                                spin_lock_bh(&pqueue->lock);
                        }
                }

                callback = pentry->callback;
                areq = pentry->areq;
                free_pentry(pentry);

                pqueue->pending_count--;
                pqueue->front = modulo_inc(pqueue->front, pqueue->qlen, 1);
                spin_unlock_bh(&pqueue->lock);

                /*
                 * Call callback after current pending entry has been
                 * processed, we don't do it if the callback pointer is
                 * invalid.
                 */
                if (callback)
                        callback(res_code, areq, info);
        }
}

void otx2_cpt_post_process(struct otx2_cptlf_wqe *wqe)
{
        process_pending_queue(wqe->lfs,
                              &wqe->lfs->lf[wqe->lf_num].pqueue);
}

int otx2_cpt_get_eng_grp_num(struct pci_dev *pdev,
                             enum otx2_cpt_eng_type eng_type)
{
        struct otx2_cptvf_dev *cptvf = pci_get_drvdata(pdev);

        switch (eng_type) {
        case OTX2_CPT_SE_TYPES:
                return cptvf->lfs.kcrypto_se_eng_grp_num;
        case OTX2_CPT_AE_TYPES:
                return cptvf->lfs.kcrypto_ae_eng_grp_num;
        default:
                dev_err(&cptvf->pdev->dev, "Unsupported engine type");
                break;
        }
        return -ENXIO;
}