// SPDX-License-Identifier: GPL-2.0-only
/*
 * Tegra host1x Job
 *
 * Copyright (c) 2010-2015, NVIDIA Corporation.
 */

#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/host1x.h>
#include <linux/iommu.h>
#include <linux/kref.h>
#include <linux/module.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <trace/events/host1x.h>

#include "channel.h"
#include "dev.h"
#include "job.h"
#include "syncpt.h"

#define HOST1X_WAIT_SYNCPT_OFFSET 0x8

struct host1x_job *host1x_job_alloc(struct host1x_channel *ch,
                                    u32 num_cmdbufs, u32 num_relocs,
                                    bool skip_firewall)
{
        struct host1x_job *job = NULL;
        unsigned int num_unpins = num_relocs;
        bool enable_firewall;
        u64 total;
        void *mem;

        enable_firewall = IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) && !skip_firewall;

        if (!enable_firewall)
                num_unpins += num_cmdbufs;

        /* Check that we're not going to overflow */
        total = sizeof(struct host1x_job) +
                (u64)num_relocs * sizeof(struct host1x_reloc) +
                (u64)num_unpins * sizeof(struct host1x_job_unpin_data) +
                (u64)num_cmdbufs * sizeof(struct host1x_job_cmd) +
                (u64)num_unpins * sizeof(dma_addr_t) +
                (u64)num_unpins * sizeof(u32 *);
        if (total > ULONG_MAX)
                return NULL;

        mem = job = kzalloc(total, GFP_KERNEL);
        if (!job)
                return NULL;

        job->enable_firewall = enable_firewall;

        kref_init(&job->ref);
        job->channel = ch;

        /* Redistribute memory to the structs  */
        mem += sizeof(struct host1x_job);
        job->relocs = num_relocs ? mem : NULL;
        mem += num_relocs * sizeof(struct host1x_reloc);
        job->unpins = num_unpins ? mem : NULL;
        mem += num_unpins * sizeof(struct host1x_job_unpin_data);
        job->cmds = num_cmdbufs ? mem : NULL;
        mem += num_cmdbufs * sizeof(struct host1x_job_cmd);
        job->addr_phys = num_unpins ? mem : NULL;

        job->reloc_addr_phys = job->addr_phys;
        job->gather_addr_phys = &job->addr_phys[num_relocs];

        return job;
}
EXPORT_SYMBOL(host1x_job_alloc);

struct host1x_job *host1x_job_get(struct host1x_job *job)
{
        kref_get(&job->ref);
        return job;
}
EXPORT_SYMBOL(host1x_job_get);

static void job_free(struct kref *ref)
{
        struct host1x_job *job = container_of(ref, struct host1x_job, ref);

        if (job->release)
                job->release(job);

        if (job->fence) {
                /*
                 * remove_callback is atomic w.r.t. fence signaling, so
                 * after the call returns, we know that the callback is not
                 * in execution, and the fence can be safely freed.
                 */
                dma_fence_remove_callback(job->fence, &job->fence_cb);
                dma_fence_put(job->fence);
        }

        if (job->syncpt)
                host1x_syncpt_put(job->syncpt);

        kfree(job);
}

void host1x_job_put(struct host1x_job *job)
{
        kref_put(&job->ref, job_free);
}
EXPORT_SYMBOL(host1x_job_put);

void host1x_job_add_gather(struct host1x_job *job, struct host1x_bo *bo,
                           unsigned int words, unsigned int offset)
{
        struct host1x_job_gather *gather = &job->cmds[job->num_cmds].gather;

        gather->words = words;
        gather->bo = bo;
        gather->offset = offset;

        job->num_cmds++;
}
EXPORT_SYMBOL(host1x_job_add_gather);

void host1x_job_add_wait(struct host1x_job *job, u32 id, u32 thresh,
                         bool relative, u32 next_class)
{
        struct host1x_job_cmd *cmd = &job->cmds[job->num_cmds];

        cmd->is_wait = true;
        cmd->wait.id = id;
        cmd->wait.threshold = thresh;
        cmd->wait.next_class = next_class;
        cmd->wait.relative = relative;

        job->num_cmds++;
}
EXPORT_SYMBOL(host1x_job_add_wait);

static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
{
        unsigned long mask = HOST1X_RELOC_READ | HOST1X_RELOC_WRITE;
        struct host1x_client *client = job->client;
        struct device *dev = client->dev;
        struct host1x_job_gather *g;
        unsigned int i;
        int err;

        job->num_unpins = 0;

        for (i = 0; i < job->num_relocs; i++) {
                struct host1x_reloc *reloc = &job->relocs[i];
                enum dma_data_direction direction;
                struct host1x_bo_mapping *map;
                struct host1x_bo *bo;

                reloc->target.bo = host1x_bo_get(reloc->target.bo);
                if (!reloc->target.bo) {
                        err = -EINVAL;
                        goto unpin;
                }

                bo = reloc->target.bo;

                switch (reloc->flags & mask) {
                case HOST1X_RELOC_READ:
                        direction = DMA_TO_DEVICE;
                        break;

                case HOST1X_RELOC_WRITE:
                        direction = DMA_FROM_DEVICE;
                        break;

                case HOST1X_RELOC_READ | HOST1X_RELOC_WRITE:
                        direction = DMA_BIDIRECTIONAL;
                        break;

                default:
                        err = -EINVAL;
                        goto unpin;
                }

                map = host1x_bo_pin(dev, bo, direction, NULL);
                if (IS_ERR(map)) {
                        err = PTR_ERR(map);
                        goto unpin;
                }

                /*
                 * host1x clients are generally not able to do scatter-gather themselves, so fail
                 * if the buffer is discontiguous and we fail to map its SG table to a single
                 * contiguous chunk of I/O virtual memory.
                 */
                if (map->chunks > 1) {
                        err = -EINVAL;
                        goto unpin;
                }

                job->addr_phys[job->num_unpins] = map->phys;
                job->unpins[job->num_unpins].map = map;
                job->num_unpins++;
        }

        /*
         * We will copy gathers BO content later, so there is no need to
         * hold and pin them.
         */
        if (job->enable_firewall)
                return 0;

        for (i = 0; i < job->num_cmds; i++) {
                struct host1x_bo_mapping *map;
                size_t gather_size = 0;
                struct scatterlist *sg;
                unsigned long shift;
                struct iova *alloc;
                unsigned int j;

                if (job->cmds[i].is_wait)
                        continue;

                g = &job->cmds[i].gather;

                g->bo = host1x_bo_get(g->bo);
                if (!g->bo) {
                        err = -EINVAL;
                        goto unpin;
                }

                map = host1x_bo_pin(host->dev, g->bo, DMA_TO_DEVICE, NULL);
                if (IS_ERR(map)) {
                        err = PTR_ERR(map);
                        goto unpin;
                }

                if (host->domain) {
                        for_each_sgtable_sg(map->sgt, sg, j)
                                gather_size += sg->length;

                        gather_size = iova_align(&host->iova, gather_size);

                        shift = iova_shift(&host->iova);
                        alloc = alloc_iova(&host->iova, gather_size >> shift,
                                           host->iova_end >> shift, true);
                        if (!alloc) {
                                err = -ENOMEM;
                                goto put;
                        }

                        err = iommu_map_sgtable(host->domain, iova_dma_addr(&host->iova, alloc),
                                                map->sgt, IOMMU_READ);
                        if (err == 0) {
                                __free_iova(&host->iova, alloc);
                                err = -EINVAL;
                                goto put;
                        }

                        map->phys = iova_dma_addr(&host->iova, alloc);
                        map->size = gather_size;
                }

                job->addr_phys[job->num_unpins] = map->phys;
                job->unpins[job->num_unpins].map = map;
                job->num_unpins++;

                job->gather_addr_phys[i] = map->phys;
        }

        return 0;

put:
        host1x_bo_put(g->bo);
unpin:
        host1x_job_unpin(job);
        return err;
}

static int do_relocs(struct host1x_job *job, struct host1x_job_gather *g)
{
        void *cmdbuf_addr = NULL;
        struct host1x_bo *cmdbuf = g->bo;
        unsigned int i;

        /* pin & patch the relocs for one gather */
        for (i = 0; i < job->num_relocs; i++) {
                struct host1x_reloc *reloc = &job->relocs[i];
                u32 reloc_addr = (job->reloc_addr_phys[i] +
                                  reloc->target.offset) >> reloc->shift;
                u32 *target;

                /* skip all other gathers */
                if (cmdbuf != reloc->cmdbuf.bo)
                        continue;

                if (job->enable_firewall) {
                        target = (u32 *)job->gather_copy_mapped +
                                        reloc->cmdbuf.offset / sizeof(u32) +
                                                g->offset / sizeof(u32);
                        goto patch_reloc;
                }

                if (!cmdbuf_addr) {
                        cmdbuf_addr = host1x_bo_mmap(cmdbuf);

                        if (unlikely(!cmdbuf_addr)) {
                                pr_err("Could not map cmdbuf for relocation\n");
                                return -ENOMEM;
                        }
                }

                target = cmdbuf_addr + reloc->cmdbuf.offset;
patch_reloc:
                *target = reloc_addr;
        }

        if (cmdbuf_addr)
                host1x_bo_munmap(cmdbuf, cmdbuf_addr);

        return 0;
}

static bool check_reloc(struct host1x_reloc *reloc, struct host1x_bo *cmdbuf,
                        unsigned int offset)
{
        offset *= sizeof(u32);

        if (reloc->cmdbuf.bo != cmdbuf || reloc->cmdbuf.offset != offset)
                return false;

        /* relocation shift value validation isn't implemented yet */
        if (reloc->shift)
                return false;

        return true;
}

struct host1x_firewall {
        struct host1x_job *job;
        struct device *dev;

        unsigned int num_relocs;
        struct host1x_reloc *reloc;

        struct host1x_bo *cmdbuf;
        unsigned int offset;

        u32 words;
        u32 class;
        u32 reg;
        u32 mask;
        u32 count;
};

static int check_register(struct host1x_firewall *fw, unsigned long offset)
{
        if (!fw->job->is_addr_reg)
                return 0;

        if (fw->job->is_addr_reg(fw->dev, fw->class, offset)) {
                if (!fw->num_relocs)
                        return -EINVAL;

                if (!check_reloc(fw->reloc, fw->cmdbuf, fw->offset))
                        return -EINVAL;

                fw->num_relocs--;
                fw->reloc++;
        }

        return 0;
}

static int check_class(struct host1x_firewall *fw, u32 class)
{
        if (!fw->job->is_valid_class) {
                if (fw->class != class)
                        return -EINVAL;
        } else {
                if (!fw->job->is_valid_class(fw->class))
                        return -EINVAL;
        }

        return 0;
}

static int check_mask(struct host1x_firewall *fw)
{
        u32 mask = fw->mask;
        u32 reg = fw->reg;
        int ret;

        while (mask) {
                if (fw->words == 0)
                        return -EINVAL;

                if (mask & 1) {
                        ret = check_register(fw, reg);
                        if (ret < 0)
                                return ret;

                        fw->words--;
                        fw->offset++;
                }
                mask >>= 1;
                reg++;
        }

        return 0;
}

static int check_incr(struct host1x_firewall *fw)
{
        u32 count = fw->count;
        u32 reg = fw->reg;
        int ret;

        while (count) {
                if (fw->words == 0)
                        return -EINVAL;

                ret = check_register(fw, reg);
                if (ret < 0)
                        return ret;

                reg++;
                fw->words--;
                fw->offset++;
                count--;
        }

        return 0;
}

static int check_nonincr(struct host1x_firewall *fw)
{
        u32 count = fw->count;
        int ret;

        while (count) {
                if (fw->words == 0)
                        return -EINVAL;

                ret = check_register(fw, fw->reg);
                if (ret < 0)
                        return ret;

                fw->words--;
                fw->offset++;
                count--;
        }

        return 0;
}

static int validate(struct host1x_firewall *fw, struct host1x_job_gather *g)
{
        u32 *cmdbuf_base = (u32 *)fw->job->gather_copy_mapped +
                (g->offset / sizeof(u32));
        u32 job_class = fw->class;
        int err = 0;

        fw->words = g->words;
        fw->cmdbuf = g->bo;
        fw->offset = 0;

        while (fw->words && !err) {
                u32 word = cmdbuf_base[fw->offset];
                u32 opcode = (word & 0xf0000000) >> 28;

                fw->mask = 0;
                fw->reg = 0;
                fw->count = 0;
                fw->words--;
                fw->offset++;

                switch (opcode) {
                case 0:
                        fw->class = word >> 6 & 0x3ff;
                        fw->mask = word & 0x3f;
                        fw->reg = word >> 16 & 0xfff;
                        err = check_class(fw, job_class);
                        if (!err)
                                err = check_mask(fw);
                        if (err)
                                goto out;
                        break;
                case 1:
                        fw->reg = word >> 16 & 0xfff;
                        fw->count = word & 0xffff;
                        err = check_incr(fw);
                        if (err)
                                goto out;
                        break;

                case 2:
                        fw->reg = word >> 16 & 0xfff;
                        fw->count = word & 0xffff;
                        err = check_nonincr(fw);
                        if (err)
                                goto out;
                        break;

                case 3:
                        fw->mask = word & 0xffff;
                        fw->reg = word >> 16 & 0xfff;
                        err = check_mask(fw);
                        if (err)
                                goto out;
                        break;
                case 4:
                case 14:
                        break;
                default:
                        err = -EINVAL;
                        break;
                }
        }

out:
        return err;
}

static inline int copy_gathers(struct device *host, struct host1x_job *job,
                               struct device *dev)
{
        struct host1x_firewall fw;
        size_t size = 0;
        size_t offset = 0;
        unsigned int i;

        fw.job = job;
        fw.dev = dev;
        fw.reloc = job->relocs;
        fw.num_relocs = job->num_relocs;
        fw.class = job->class;

        for (i = 0; i < job->num_cmds; i++) {
                struct host1x_job_gather *g;

                if (job->cmds[i].is_wait)
                        continue;

                g = &job->cmds[i].gather;

                size += g->words * sizeof(u32);
        }

        /*
         * Try a non-blocking allocation from a higher priority pools first,
         * as awaiting for the allocation here is a major performance hit.
         */
        job->gather_copy_mapped = dma_alloc_wc(host, size, &job->gather_copy,
                                               GFP_NOWAIT);

        /* the higher priority allocation failed, try the generic-blocking */
        if (!job->gather_copy_mapped)
                job->gather_copy_mapped = dma_alloc_wc(host, size,
                                                       &job->gather_copy,
                                                       GFP_KERNEL);
        if (!job->gather_copy_mapped)
                return -ENOMEM;

        job->gather_copy_size = size;

        for (i = 0; i < job->num_cmds; i++) {
                struct host1x_job_gather *g;
                void *gather;

                if (job->cmds[i].is_wait)
                        continue;
                g = &job->cmds[i].gather;

                /* Copy the gather */
                gather = host1x_bo_mmap(g->bo);
                memcpy(job->gather_copy_mapped + offset, gather + g->offset,
                       g->words * sizeof(u32));
                host1x_bo_munmap(g->bo, gather);

                /* Store the location in the buffer */
                g->base = job->gather_copy;
                g->offset = offset;

                /* Validate the job */
                if (validate(&fw, g))
                        return -EINVAL;

                offset += g->words * sizeof(u32);
        }

        /* No relocs should remain at this point */
        if (fw.num_relocs)
                return -EINVAL;

        return 0;
}

int host1x_job_pin(struct host1x_job *job, struct device *dev)
{
        int err;
        unsigned int i, j;
        struct host1x *host = dev_get_drvdata(dev->parent);

        /* pin memory */
        err = pin_job(host, job);
        if (err)
                goto out;

        if (job->enable_firewall) {
                err = copy_gathers(host->dev, job, dev);
                if (err)
                        goto out;
        }

        /* patch gathers */
        for (i = 0; i < job->num_cmds; i++) {
                struct host1x_job_gather *g;

                if (job->cmds[i].is_wait)
                        continue;
                g = &job->cmds[i].gather;

                /* process each gather mem only once */
                if (g->handled)
                        continue;

                /* copy_gathers() sets gathers base if firewall is enabled */
                if (!job->enable_firewall)
                        g->base = job->gather_addr_phys[i];

                for (j = i + 1; j < job->num_cmds; j++) {
                        if (!job->cmds[j].is_wait &&
                            job->cmds[j].gather.bo == g->bo) {
                                job->cmds[j].gather.handled = true;
                                job->cmds[j].gather.base = g->base;
                        }
                }

                err = do_relocs(job, g);
                if (err)
                        break;
        }

out:
        if (err)
                host1x_job_unpin(job);
        wmb();

        return err;
}
EXPORT_SYMBOL(host1x_job_pin);

void host1x_job_unpin(struct host1x_job *job)
{
        struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
        unsigned int i;

        for (i = 0; i < job->num_unpins; i++) {
                struct host1x_bo_mapping *map = job->unpins[i].map;
                struct host1x_bo *bo = map->bo;

                if (!job->enable_firewall && map->size && host->domain) {
                        iommu_unmap(host->domain, job->addr_phys[i], map->size);
                        free_iova(&host->iova, iova_pfn(&host->iova, job->addr_phys[i]));
                }

                host1x_bo_unpin(map);
                host1x_bo_put(bo);
        }

        job->num_unpins = 0;

        if (job->gather_copy_size)
                dma_free_wc(host->dev, job->gather_copy_size,
                            job->gather_copy_mapped, job->gather_copy);
}
EXPORT_SYMBOL(host1x_job_unpin);

/*
 * Debug routine used to dump job entries
 */
void host1x_job_dump(struct device *dev, struct host1x_job *job)
{
        dev_dbg(dev, "    SYNCPT_ID   %d\n", job->syncpt->id);
        dev_dbg(dev, "    SYNCPT_VAL  %d\n", job->syncpt_end);
        dev_dbg(dev, "    FIRST_GET   0x%x\n", job->first_get);
        dev_dbg(dev, "    TIMEOUT     %d\n", job->timeout);
        dev_dbg(dev, "    NUM_SLOTS   %d\n", job->num_slots);
        dev_dbg(dev, "    NUM_HANDLES %d\n", job->num_unpins);
}