treewide: remove redundant IS_ERR() before error code check

[linux/fpc-iii.git] / drivers / gpu / drm / msm / msm_drv.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 */

#include <linux/dma-mapping.h>
#include <linux/kthread.h>
#include <linux/uaccess.h>
#include <uapi/linux/sched/types.h>

#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_ioctl.h>
#include <drm/drm_irq.h>
#include <drm/drm_prime.h>
#include <drm/drm_of.h>
#include <drm/drm_vblank.h>

#include "msm_drv.h"
#include "msm_debugfs.h"
#include "msm_fence.h"
#include "msm_gem.h"
#include "msm_gpu.h"
#include "msm_kms.h"
#include "adreno/adreno_gpu.h"

/*
 * MSM driver version:
 * - 1.0.0 - initial interface
 * - 1.1.0 - adds madvise, and support for submits with > 4 cmd buffers
 * - 1.2.0 - adds explicit fence support for submit ioctl
 * - 1.3.0 - adds GMEM_BASE + NR_RINGS params, SUBMITQUEUE_NEW +
 *           SUBMITQUEUE_CLOSE ioctls, and MSM_INFO_IOVA flag for
 *           MSM_GEM_INFO ioctl.
 * - 1.4.0 - softpin, MSM_RELOC_BO_DUMP, and GEM_INFO support to set/get
 *           GEM object's debug name
 * - 1.5.0 - Add SUBMITQUERY_QUERY ioctl
 */
#define MSM_VERSION_MAJOR       1
#define MSM_VERSION_MINOR       5
#define MSM_VERSION_PATCHLEVEL  0

static const struct drm_mode_config_funcs mode_config_funcs = {
        .fb_create = msm_framebuffer_create,
        .output_poll_changed = drm_fb_helper_output_poll_changed,
        .atomic_check = drm_atomic_helper_check,
        .atomic_commit = drm_atomic_helper_commit,
};

static const struct drm_mode_config_helper_funcs mode_config_helper_funcs = {
        .atomic_commit_tail = msm_atomic_commit_tail,
};

#ifdef CONFIG_DRM_MSM_REGISTER_LOGGING
static bool reglog = false;
MODULE_PARM_DESC(reglog, "Enable register read/write logging");
module_param(reglog, bool, 0600);
#else
#define reglog 0
#endif

#ifdef CONFIG_DRM_FBDEV_EMULATION
static bool fbdev = true;
MODULE_PARM_DESC(fbdev, "Enable fbdev compat layer");
module_param(fbdev, bool, 0600);
#endif

static char *vram = "16m";
MODULE_PARM_DESC(vram, "Configure VRAM size (for devices without IOMMU/GPUMMU)");
module_param(vram, charp, 0);

bool dumpstate = false;
MODULE_PARM_DESC(dumpstate, "Dump KMS state on errors");
module_param(dumpstate, bool, 0600);

static bool modeset = true;
MODULE_PARM_DESC(modeset, "Use kernel modesetting [KMS] (1=on (default), 0=disable)");
module_param(modeset, bool, 0600);

/*
 * Util/helpers:
 */

struct clk *msm_clk_bulk_get_clock(struct clk_bulk_data *bulk, int count,
                const char *name)
{
        int i;
        char n[32];

        snprintf(n, sizeof(n), "%s_clk", name);

        for (i = 0; bulk && i < count; i++) {
                if (!strcmp(bulk[i].id, name) || !strcmp(bulk[i].id, n))
                        return bulk[i].clk;
        }


        return NULL;
}

struct clk *msm_clk_get(struct platform_device *pdev, const char *name)
{
        struct clk *clk;
        char name2[32];

        clk = devm_clk_get(&pdev->dev, name);
        if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER)
                return clk;

        snprintf(name2, sizeof(name2), "%s_clk", name);

        clk = devm_clk_get(&pdev->dev, name2);
        if (!IS_ERR(clk))
                dev_warn(&pdev->dev, "Using legacy clk name binding.  Use "
                                "\"%s\" instead of \"%s\"\n", name, name2);

        return clk;
}

void __iomem *msm_ioremap(struct platform_device *pdev, const char *name,
                const char *dbgname)
{
        struct resource *res;
        unsigned long size;
        void __iomem *ptr;

        if (name)
                res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
        else
                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

        if (!res) {
                DRM_DEV_ERROR(&pdev->dev, "failed to get memory resource: %s\n", name);
                return ERR_PTR(-EINVAL);
        }

        size = resource_size(res);

        ptr = devm_ioremap(&pdev->dev, res->start, size);
        if (!ptr) {
                DRM_DEV_ERROR(&pdev->dev, "failed to ioremap: %s\n", name);
                return ERR_PTR(-ENOMEM);
        }

        if (reglog)
                printk(KERN_DEBUG "IO:region %s %p %08lx\n", dbgname, ptr, size);

        return ptr;
}

void msm_writel(u32 data, void __iomem *addr)
{
        if (reglog)
                printk(KERN_DEBUG "IO:W %p %08x\n", addr, data);
        writel(data, addr);
}

u32 msm_readl(const void __iomem *addr)
{
        u32 val = readl(addr);
        if (reglog)
                pr_err("IO:R %p %08x\n", addr, val);
        return val;
}

struct msm_vblank_work {
        struct work_struct work;
        int crtc_id;
        bool enable;
        struct msm_drm_private *priv;
};

static void vblank_ctrl_worker(struct work_struct *work)
{
        struct msm_vblank_work *vbl_work = container_of(work,
                                                struct msm_vblank_work, work);
        struct msm_drm_private *priv = vbl_work->priv;
        struct msm_kms *kms = priv->kms;

        if (vbl_work->enable)
                kms->funcs->enable_vblank(kms, priv->crtcs[vbl_work->crtc_id]);
        else
                kms->funcs->disable_vblank(kms, priv->crtcs[vbl_work->crtc_id]);

        kfree(vbl_work);
}

static int vblank_ctrl_queue_work(struct msm_drm_private *priv,
                                        int crtc_id, bool enable)
{
        struct msm_vblank_work *vbl_work;

        vbl_work = kzalloc(sizeof(*vbl_work), GFP_ATOMIC);
        if (!vbl_work)
                return -ENOMEM;

        INIT_WORK(&vbl_work->work, vblank_ctrl_worker);

        vbl_work->crtc_id = crtc_id;
        vbl_work->enable = enable;
        vbl_work->priv = priv;

        queue_work(priv->wq, &vbl_work->work);

        return 0;
}

static int msm_drm_uninit(struct device *dev)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct drm_device *ddev = platform_get_drvdata(pdev);
        struct msm_drm_private *priv = ddev->dev_private;
        struct msm_kms *kms = priv->kms;
        struct msm_mdss *mdss = priv->mdss;
        int i;

        /*
         * Shutdown the hw if we're far enough along where things might be on.
         * If we run this too early, we'll end up panicking in any variety of
         * places. Since we don't register the drm device until late in
         * msm_drm_init, drm_dev->registered is used as an indicator that the
         * shutdown will be successful.
         */
        if (ddev->registered) {
                drm_dev_unregister(ddev);
                drm_atomic_helper_shutdown(ddev);
        }

        /* We must cancel and cleanup any pending vblank enable/disable
         * work before drm_irq_uninstall() to avoid work re-enabling an
         * irq after uninstall has disabled it.
         */

        flush_workqueue(priv->wq);

        /* clean up event worker threads */
        for (i = 0; i < priv->num_crtcs; i++) {
                if (priv->event_thread[i].thread) {
                        kthread_destroy_worker(&priv->event_thread[i].worker);
                        priv->event_thread[i].thread = NULL;
                }
        }

        msm_gem_shrinker_cleanup(ddev);

        drm_kms_helper_poll_fini(ddev);

        msm_perf_debugfs_cleanup(priv);
        msm_rd_debugfs_cleanup(priv);

#ifdef CONFIG_DRM_FBDEV_EMULATION
        if (fbdev && priv->fbdev)
                msm_fbdev_free(ddev);
#endif

        drm_mode_config_cleanup(ddev);

        pm_runtime_get_sync(dev);
        drm_irq_uninstall(ddev);
        pm_runtime_put_sync(dev);

        if (kms && kms->funcs)
                kms->funcs->destroy(kms);

        if (priv->vram.paddr) {
                unsigned long attrs = DMA_ATTR_NO_KERNEL_MAPPING;
                drm_mm_takedown(&priv->vram.mm);
                dma_free_attrs(dev, priv->vram.size, NULL,
                               priv->vram.paddr, attrs);
        }

        component_unbind_all(dev, ddev);

        if (mdss && mdss->funcs)
                mdss->funcs->destroy(ddev);

        ddev->dev_private = NULL;
        drm_dev_put(ddev);

        destroy_workqueue(priv->wq);
        kfree(priv);

        return 0;
}

#define KMS_MDP4 4
#define KMS_MDP5 5
#define KMS_DPU  3

static int get_mdp_ver(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;

        return (int) (unsigned long) of_device_get_match_data(dev);
}

#include <linux/of_address.h>

bool msm_use_mmu(struct drm_device *dev)
{
        struct msm_drm_private *priv = dev->dev_private;

        /* a2xx comes with its own MMU */
        return priv->is_a2xx || iommu_present(&platform_bus_type);
}

static int msm_init_vram(struct drm_device *dev)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct device_node *node;
        unsigned long size = 0;
        int ret = 0;

        /* In the device-tree world, we could have a 'memory-region'
         * phandle, which gives us a link to our "vram".  Allocating
         * is all nicely abstracted behind the dma api, but we need
         * to know the entire size to allocate it all in one go. There
         * are two cases:
         *  1) device with no IOMMU, in which case we need exclusive
         *     access to a VRAM carveout big enough for all gpu
         *     buffers
         *  2) device with IOMMU, but where the bootloader puts up
         *     a splash screen.  In this case, the VRAM carveout
         *     need only be large enough for fbdev fb.  But we need
         *     exclusive access to the buffer to avoid the kernel
         *     using those pages for other purposes (which appears
         *     as corruption on screen before we have a chance to
         *     load and do initial modeset)
         */

        node = of_parse_phandle(dev->dev->of_node, "memory-region", 0);
        if (node) {
                struct resource r;
                ret = of_address_to_resource(node, 0, &r);
                of_node_put(node);
                if (ret)
                        return ret;
                size = r.end - r.start;
                DRM_INFO("using VRAM carveout: %lx@%pa\n", size, &r.start);

                /* if we have no IOMMU, then we need to use carveout allocator.
                 * Grab the entire CMA chunk carved out in early startup in
                 * mach-msm:
                 */
        } else if (!msm_use_mmu(dev)) {
                DRM_INFO("using %s VRAM carveout\n", vram);
                size = memparse(vram, NULL);
        }

        if (size) {
                unsigned long attrs = 0;
                void *p;

                priv->vram.size = size;

                drm_mm_init(&priv->vram.mm, 0, (size >> PAGE_SHIFT) - 1);
                spin_lock_init(&priv->vram.lock);

                attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
                attrs |= DMA_ATTR_WRITE_COMBINE;

                /* note that for no-kernel-mapping, the vaddr returned
                 * is bogus, but non-null if allocation succeeded:
                 */
                p = dma_alloc_attrs(dev->dev, size,
                                &priv->vram.paddr, GFP_KERNEL, attrs);
                if (!p) {
                        DRM_DEV_ERROR(dev->dev, "failed to allocate VRAM\n");
                        priv->vram.paddr = 0;
                        return -ENOMEM;
                }

                DRM_DEV_INFO(dev->dev, "VRAM: %08x->%08x\n",
                                (uint32_t)priv->vram.paddr,
                                (uint32_t)(priv->vram.paddr + size));
        }

        return ret;
}

static int msm_drm_init(struct device *dev, struct drm_driver *drv)
{
        struct platform_device *pdev = to_platform_device(dev);
        struct drm_device *ddev;
        struct msm_drm_private *priv;
        struct msm_kms *kms;
        struct msm_mdss *mdss;
        int ret, i;
        struct sched_param param;

        ddev = drm_dev_alloc(drv, dev);
        if (IS_ERR(ddev)) {
                DRM_DEV_ERROR(dev, "failed to allocate drm_device\n");
                return PTR_ERR(ddev);
        }

        platform_set_drvdata(pdev, ddev);

        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
        if (!priv) {
                ret = -ENOMEM;
                goto err_put_drm_dev;
        }

        ddev->dev_private = priv;
        priv->dev = ddev;

        switch (get_mdp_ver(pdev)) {
        case KMS_MDP5:
                ret = mdp5_mdss_init(ddev);
                break;
        case KMS_DPU:
                ret = dpu_mdss_init(ddev);
                break;
        default:
                ret = 0;
                break;
        }
        if (ret)
                goto err_free_priv;

        mdss = priv->mdss;

        priv->wq = alloc_ordered_workqueue("msm", 0);

        INIT_WORK(&priv->free_work, msm_gem_free_work);
        init_llist_head(&priv->free_list);

        INIT_LIST_HEAD(&priv->inactive_list);

        drm_mode_config_init(ddev);

        /* Bind all our sub-components: */
        ret = component_bind_all(dev, ddev);
        if (ret)
                goto err_destroy_mdss;

        ret = msm_init_vram(ddev);
        if (ret)
                goto err_msm_uninit;

        msm_gem_shrinker_init(ddev);

        switch (get_mdp_ver(pdev)) {
        case KMS_MDP4:
                kms = mdp4_kms_init(ddev);
                priv->kms = kms;
                break;
        case KMS_MDP5:
                kms = mdp5_kms_init(ddev);
                break;
        case KMS_DPU:
                kms = dpu_kms_init(ddev);
                priv->kms = kms;
                break;
        default:
                /* valid only for the dummy headless case, where of_node=NULL */
                WARN_ON(dev->of_node);
                kms = NULL;
                break;
        }

        if (IS_ERR(kms)) {
                DRM_DEV_ERROR(dev, "failed to load kms\n");
                ret = PTR_ERR(kms);
                priv->kms = NULL;
                goto err_msm_uninit;
        }

        /* Enable normalization of plane zpos */
        ddev->mode_config.normalize_zpos = true;

        if (kms) {
                kms->dev = ddev;
                ret = kms->funcs->hw_init(kms);
                if (ret) {
                        DRM_DEV_ERROR(dev, "kms hw init failed: %d\n", ret);
                        goto err_msm_uninit;
                }
        }

        ddev->mode_config.funcs = &mode_config_funcs;
        ddev->mode_config.helper_private = &mode_config_helper_funcs;

        /**
         * this priority was found during empiric testing to have appropriate
         * realtime scheduling to process display updates and interact with
         * other real time and normal priority task
         */
        param.sched_priority = 16;
        for (i = 0; i < priv->num_crtcs; i++) {
                /* initialize event thread */
                priv->event_thread[i].crtc_id = priv->crtcs[i]->base.id;
                kthread_init_worker(&priv->event_thread[i].worker);
                priv->event_thread[i].dev = ddev;
                priv->event_thread[i].thread =
                        kthread_run(kthread_worker_fn,
                                &priv->event_thread[i].worker,
                                "crtc_event:%d", priv->event_thread[i].crtc_id);
                if (IS_ERR(priv->event_thread[i].thread)) {
                        DRM_DEV_ERROR(dev, "failed to create crtc_event kthread\n");
                        priv->event_thread[i].thread = NULL;
                        goto err_msm_uninit;
                }

                ret = sched_setscheduler(priv->event_thread[i].thread,
                                         SCHED_FIFO, &param);
                if (ret)
                        dev_warn(dev, "event_thread set priority failed:%d\n",
                                 ret);
        }

        ret = drm_vblank_init(ddev, priv->num_crtcs);
        if (ret < 0) {
                DRM_DEV_ERROR(dev, "failed to initialize vblank\n");
                goto err_msm_uninit;
        }

        if (kms) {
                pm_runtime_get_sync(dev);
                ret = drm_irq_install(ddev, kms->irq);
                pm_runtime_put_sync(dev);
                if (ret < 0) {
                        DRM_DEV_ERROR(dev, "failed to install IRQ handler\n");
                        goto err_msm_uninit;
                }
        }

        ret = drm_dev_register(ddev, 0);
        if (ret)
                goto err_msm_uninit;

        drm_mode_config_reset(ddev);

#ifdef CONFIG_DRM_FBDEV_EMULATION
        if (kms && fbdev)
                priv->fbdev = msm_fbdev_init(ddev);
#endif

        ret = msm_debugfs_late_init(ddev);
        if (ret)
                goto err_msm_uninit;

        drm_kms_helper_poll_init(ddev);

        return 0;

err_msm_uninit:
        msm_drm_uninit(dev);
        return ret;
err_destroy_mdss:
        if (mdss && mdss->funcs)
                mdss->funcs->destroy(ddev);
err_free_priv:
        kfree(priv);
err_put_drm_dev:
        drm_dev_put(ddev);
        return ret;
}

/*
 * DRM operations:
 */

static void load_gpu(struct drm_device *dev)
{
        static DEFINE_MUTEX(init_lock);
        struct msm_drm_private *priv = dev->dev_private;

        mutex_lock(&init_lock);

        if (!priv->gpu)
                priv->gpu = adreno_load_gpu(dev);

        mutex_unlock(&init_lock);
}

static int context_init(struct drm_device *dev, struct drm_file *file)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_file_private *ctx;

        ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
        if (!ctx)
                return -ENOMEM;

        msm_submitqueue_init(dev, ctx);

        ctx->aspace = priv->gpu ? priv->gpu->aspace : NULL;
        file->driver_priv = ctx;

        return 0;
}

static int msm_open(struct drm_device *dev, struct drm_file *file)
{
        /* For now, load gpu on open.. to avoid the requirement of having
         * firmware in the initrd.
         */
        load_gpu(dev);

        return context_init(dev, file);
}

static void context_close(struct msm_file_private *ctx)
{
        msm_submitqueue_close(ctx);
        kfree(ctx);
}

static void msm_postclose(struct drm_device *dev, struct drm_file *file)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_file_private *ctx = file->driver_priv;

        mutex_lock(&dev->struct_mutex);
        if (ctx == priv->lastctx)
                priv->lastctx = NULL;
        mutex_unlock(&dev->struct_mutex);

        context_close(ctx);
}

static irqreturn_t msm_irq(int irq, void *arg)
{
        struct drm_device *dev = arg;
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        BUG_ON(!kms);
        return kms->funcs->irq(kms);
}

static void msm_irq_preinstall(struct drm_device *dev)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        BUG_ON(!kms);
        kms->funcs->irq_preinstall(kms);
}

static int msm_irq_postinstall(struct drm_device *dev)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        BUG_ON(!kms);

        if (kms->funcs->irq_postinstall)
                return kms->funcs->irq_postinstall(kms);

        return 0;
}

static void msm_irq_uninstall(struct drm_device *dev)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        BUG_ON(!kms);
        kms->funcs->irq_uninstall(kms);
}

static int msm_enable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        if (!kms)
                return -ENXIO;
        DBG("dev=%p, crtc=%u", dev, pipe);
        return vblank_ctrl_queue_work(priv, pipe, true);
}

static void msm_disable_vblank(struct drm_device *dev, unsigned int pipe)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct msm_kms *kms = priv->kms;
        if (!kms)
                return;
        DBG("dev=%p, crtc=%u", dev, pipe);
        vblank_ctrl_queue_work(priv, pipe, false);
}

/*
 * DRM ioctls:
 */

static int msm_ioctl_get_param(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct drm_msm_param *args = data;
        struct msm_gpu *gpu;

        /* for now, we just have 3d pipe.. eventually this would need to
         * be more clever to dispatch to appropriate gpu module:
         */
        if (args->pipe != MSM_PIPE_3D0)
                return -EINVAL;

        gpu = priv->gpu;

        if (!gpu)
                return -ENXIO;

        return gpu->funcs->get_param(gpu, args->param, &args->value);
}

static int msm_ioctl_gem_new(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_gem_new *args = data;

        if (args->flags & ~MSM_BO_FLAGS) {
                DRM_ERROR("invalid flags: %08x\n", args->flags);
                return -EINVAL;
        }

        return msm_gem_new_handle(dev, file, args->size,
                        args->flags, &args->handle, NULL);
}

static inline ktime_t to_ktime(struct drm_msm_timespec timeout)
{
        return ktime_set(timeout.tv_sec, timeout.tv_nsec);
}

static int msm_ioctl_gem_cpu_prep(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_gem_cpu_prep *args = data;
        struct drm_gem_object *obj;
        ktime_t timeout = to_ktime(args->timeout);
        int ret;

        if (args->op & ~MSM_PREP_FLAGS) {
                DRM_ERROR("invalid op: %08x\n", args->op);
                return -EINVAL;
        }

        obj = drm_gem_object_lookup(file, args->handle);
        if (!obj)
                return -ENOENT;

        ret = msm_gem_cpu_prep(obj, args->op, &timeout);

        drm_gem_object_put_unlocked(obj);

        return ret;
}

static int msm_ioctl_gem_cpu_fini(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_gem_cpu_fini *args = data;
        struct drm_gem_object *obj;
        int ret;

        obj = drm_gem_object_lookup(file, args->handle);
        if (!obj)
                return -ENOENT;

        ret = msm_gem_cpu_fini(obj);

        drm_gem_object_put_unlocked(obj);

        return ret;
}

static int msm_ioctl_gem_info_iova(struct drm_device *dev,
                struct drm_gem_object *obj, uint64_t *iova)
{
        struct msm_drm_private *priv = dev->dev_private;

        if (!priv->gpu)
                return -EINVAL;

        /*
         * Don't pin the memory here - just get an address so that userspace can
         * be productive
         */
        return msm_gem_get_iova(obj, priv->gpu->aspace, iova);
}

static int msm_ioctl_gem_info(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_gem_info *args = data;
        struct drm_gem_object *obj;
        struct msm_gem_object *msm_obj;
        int i, ret = 0;

        if (args->pad)
                return -EINVAL;

        switch (args->info) {
        case MSM_INFO_GET_OFFSET:
        case MSM_INFO_GET_IOVA:
                /* value returned as immediate, not pointer, so len==0: */
                if (args->len)
                        return -EINVAL;
                break;
        case MSM_INFO_SET_NAME:
        case MSM_INFO_GET_NAME:
                break;
        default:
                return -EINVAL;
        }

        obj = drm_gem_object_lookup(file, args->handle);
        if (!obj)
                return -ENOENT;

        msm_obj = to_msm_bo(obj);

        switch (args->info) {
        case MSM_INFO_GET_OFFSET:
                args->value = msm_gem_mmap_offset(obj);
                break;
        case MSM_INFO_GET_IOVA:
                ret = msm_ioctl_gem_info_iova(dev, obj, &args->value);
                break;
        case MSM_INFO_SET_NAME:
                /* length check should leave room for terminating null: */
                if (args->len >= sizeof(msm_obj->name)) {
                        ret = -EINVAL;
                        break;
                }
                if (copy_from_user(msm_obj->name, u64_to_user_ptr(args->value),
                                   args->len)) {
                        msm_obj->name[0] = '\0';
                        ret = -EFAULT;
                        break;
                }
                msm_obj->name[args->len] = '\0';
                for (i = 0; i < args->len; i++) {
                        if (!isprint(msm_obj->name[i])) {
                                msm_obj->name[i] = '\0';
                                break;
                        }
                }
                break;
        case MSM_INFO_GET_NAME:
                if (args->value && (args->len < strlen(msm_obj->name))) {
                        ret = -EINVAL;
                        break;
                }
                args->len = strlen(msm_obj->name);
                if (args->value) {
                        if (copy_to_user(u64_to_user_ptr(args->value),
                                         msm_obj->name, args->len))
                                ret = -EFAULT;
                }
                break;
        }

        drm_gem_object_put_unlocked(obj);

        return ret;
}

static int msm_ioctl_wait_fence(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct msm_drm_private *priv = dev->dev_private;
        struct drm_msm_wait_fence *args = data;
        ktime_t timeout = to_ktime(args->timeout);
        struct msm_gpu_submitqueue *queue;
        struct msm_gpu *gpu = priv->gpu;
        int ret;

        if (args->pad) {
                DRM_ERROR("invalid pad: %08x\n", args->pad);
                return -EINVAL;
        }

        if (!gpu)
                return 0;

        queue = msm_submitqueue_get(file->driver_priv, args->queueid);
        if (!queue)
                return -ENOENT;

        ret = msm_wait_fence(gpu->rb[queue->prio]->fctx, args->fence, &timeout,
                true);

        msm_submitqueue_put(queue);
        return ret;
}

static int msm_ioctl_gem_madvise(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_gem_madvise *args = data;
        struct drm_gem_object *obj;
        int ret;

        switch (args->madv) {
        case MSM_MADV_DONTNEED:
        case MSM_MADV_WILLNEED:
                break;
        default:
                return -EINVAL;
        }

        ret = mutex_lock_interruptible(&dev->struct_mutex);
        if (ret)
                return ret;

        obj = drm_gem_object_lookup(file, args->handle);
        if (!obj) {
                ret = -ENOENT;
                goto unlock;
        }

        ret = msm_gem_madvise(obj, args->madv);
        if (ret >= 0) {
                args->retained = ret;
                ret = 0;
        }

        drm_gem_object_put(obj);

unlock:
        mutex_unlock(&dev->struct_mutex);
        return ret;
}


static int msm_ioctl_submitqueue_new(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        struct drm_msm_submitqueue *args = data;

        if (args->flags & ~MSM_SUBMITQUEUE_FLAGS)
                return -EINVAL;

        return msm_submitqueue_create(dev, file->driver_priv, args->prio,
                args->flags, &args->id);
}

static int msm_ioctl_submitqueue_query(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        return msm_submitqueue_query(dev, file->driver_priv, data);
}

static int msm_ioctl_submitqueue_close(struct drm_device *dev, void *data,
                struct drm_file *file)
{
        u32 id = *(u32 *) data;

        return msm_submitqueue_remove(file->driver_priv, id);
}

static const struct drm_ioctl_desc msm_ioctls[] = {
        DRM_IOCTL_DEF_DRV(MSM_GET_PARAM,    msm_ioctl_get_param,    DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_NEW,      msm_ioctl_gem_new,      DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_INFO,     msm_ioctl_gem_info,     DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_CPU_PREP, msm_ioctl_gem_cpu_prep, DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_CPU_FINI, msm_ioctl_gem_cpu_fini, DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_SUBMIT,   msm_ioctl_gem_submit,   DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_WAIT_FENCE,   msm_ioctl_wait_fence,   DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_GEM_MADVISE,  msm_ioctl_gem_madvise,  DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_SUBMITQUEUE_NEW,   msm_ioctl_submitqueue_new,   DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_SUBMITQUEUE_CLOSE, msm_ioctl_submitqueue_close, DRM_RENDER_ALLOW),
        DRM_IOCTL_DEF_DRV(MSM_SUBMITQUEUE_QUERY, msm_ioctl_submitqueue_query, DRM_RENDER_ALLOW),
};

static const struct vm_operations_struct vm_ops = {
        .fault = msm_gem_fault,
        .open = drm_gem_vm_open,
        .close = drm_gem_vm_close,
};

static const struct file_operations fops = {
        .owner              = THIS_MODULE,
        .open               = drm_open,
        .release            = drm_release,
        .unlocked_ioctl     = drm_ioctl,
        .compat_ioctl       = drm_compat_ioctl,
        .poll               = drm_poll,
        .read               = drm_read,
        .llseek             = no_llseek,
        .mmap               = msm_gem_mmap,
};

static struct drm_driver msm_driver = {
        .driver_features    = DRIVER_GEM |
                                DRIVER_RENDER |
                                DRIVER_ATOMIC |
                                DRIVER_MODESET,
        .open               = msm_open,
        .postclose           = msm_postclose,
        .lastclose          = drm_fb_helper_lastclose,
        .irq_handler        = msm_irq,
        .irq_preinstall     = msm_irq_preinstall,
        .irq_postinstall    = msm_irq_postinstall,
        .irq_uninstall      = msm_irq_uninstall,
        .enable_vblank      = msm_enable_vblank,
        .disable_vblank     = msm_disable_vblank,
        .gem_free_object_unlocked = msm_gem_free_object,
        .gem_vm_ops         = &vm_ops,
        .dumb_create        = msm_gem_dumb_create,
        .dumb_map_offset    = msm_gem_dumb_map_offset,
        .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
        .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
        .gem_prime_pin      = msm_gem_prime_pin,
        .gem_prime_unpin    = msm_gem_prime_unpin,
        .gem_prime_get_sg_table = msm_gem_prime_get_sg_table,
        .gem_prime_import_sg_table = msm_gem_prime_import_sg_table,
        .gem_prime_vmap     = msm_gem_prime_vmap,
        .gem_prime_vunmap   = msm_gem_prime_vunmap,
        .gem_prime_mmap     = msm_gem_prime_mmap,
#ifdef CONFIG_DEBUG_FS
        .debugfs_init       = msm_debugfs_init,
#endif
        .ioctls             = msm_ioctls,
        .num_ioctls         = ARRAY_SIZE(msm_ioctls),
        .fops               = &fops,
        .name               = "msm",
        .desc               = "MSM Snapdragon DRM",
        .date               = "20130625",
        .major              = MSM_VERSION_MAJOR,
        .minor              = MSM_VERSION_MINOR,
        .patchlevel         = MSM_VERSION_PATCHLEVEL,
};

#ifdef CONFIG_PM_SLEEP
static int msm_pm_suspend(struct device *dev)
{
        struct drm_device *ddev = dev_get_drvdata(dev);
        struct msm_drm_private *priv = ddev->dev_private;

        if (WARN_ON(priv->pm_state))
                drm_atomic_state_put(priv->pm_state);

        priv->pm_state = drm_atomic_helper_suspend(ddev);
        if (IS_ERR(priv->pm_state)) {
                int ret = PTR_ERR(priv->pm_state);
                DRM_ERROR("Failed to suspend dpu, %d\n", ret);
                return ret;
        }

        return 0;
}

static int msm_pm_resume(struct device *dev)
{
        struct drm_device *ddev = dev_get_drvdata(dev);
        struct msm_drm_private *priv = ddev->dev_private;
        int ret;

        if (WARN_ON(!priv->pm_state))
                return -ENOENT;

        ret = drm_atomic_helper_resume(ddev, priv->pm_state);
        if (!ret)
                priv->pm_state = NULL;

        return ret;
}
#endif

#ifdef CONFIG_PM
static int msm_runtime_suspend(struct device *dev)
{
        struct drm_device *ddev = dev_get_drvdata(dev);
        struct msm_drm_private *priv = ddev->dev_private;
        struct msm_mdss *mdss = priv->mdss;

        DBG("");

        if (mdss && mdss->funcs)
                return mdss->funcs->disable(mdss);

        return 0;
}

static int msm_runtime_resume(struct device *dev)
{
        struct drm_device *ddev = dev_get_drvdata(dev);
        struct msm_drm_private *priv = ddev->dev_private;
        struct msm_mdss *mdss = priv->mdss;

        DBG("");

        if (mdss && mdss->funcs)
                return mdss->funcs->enable(mdss);

        return 0;
}
#endif

static const struct dev_pm_ops msm_pm_ops = {
        SET_SYSTEM_SLEEP_PM_OPS(msm_pm_suspend, msm_pm_resume)
        SET_RUNTIME_PM_OPS(msm_runtime_suspend, msm_runtime_resume, NULL)
};

/*
 * Componentized driver support:
 */

/*
 * NOTE: duplication of the same code as exynos or imx (or probably any other).
 * so probably some room for some helpers
 */
static int compare_of(struct device *dev, void *data)
{
        return dev->of_node == data;
}

/*
 * Identify what components need to be added by parsing what remote-endpoints
 * our MDP output ports are connected to. In the case of LVDS on MDP4, there
 * is no external component that we need to add since LVDS is within MDP4
 * itself.
 */
static int add_components_mdp(struct device *mdp_dev,
                              struct component_match **matchptr)
{
        struct device_node *np = mdp_dev->of_node;
        struct device_node *ep_node;
        struct device *master_dev;

        /*
         * on MDP4 based platforms, the MDP platform device is the component
         * master that adds other display interface components to itself.
         *
         * on MDP5 based platforms, the MDSS platform device is the component
         * master that adds MDP5 and other display interface components to
         * itself.
         */
        if (of_device_is_compatible(np, "qcom,mdp4"))
                master_dev = mdp_dev;
        else
                master_dev = mdp_dev->parent;

        for_each_endpoint_of_node(np, ep_node) {
                struct device_node *intf;
                struct of_endpoint ep;
                int ret;

                ret = of_graph_parse_endpoint(ep_node, &ep);
                if (ret) {
                        DRM_DEV_ERROR(mdp_dev, "unable to parse port endpoint\n");
                        of_node_put(ep_node);
                        return ret;
                }

                /*
                 * The LCDC/LVDS port on MDP4 is a speacial case where the
                 * remote-endpoint isn't a component that we need to add
                 */
                if (of_device_is_compatible(np, "qcom,mdp4") &&
                    ep.port == 0)
                        continue;

                /*
                 * It's okay if some of the ports don't have a remote endpoint
                 * specified. It just means that the port isn't connected to
                 * any external interface.
                 */
                intf = of_graph_get_remote_port_parent(ep_node);
                if (!intf)
                        continue;

                if (of_device_is_available(intf))
                        drm_of_component_match_add(master_dev, matchptr,
                                                   compare_of, intf);

                of_node_put(intf);
        }

        return 0;
}

static int compare_name_mdp(struct device *dev, void *data)
{
        return (strstr(dev_name(dev), "mdp") != NULL);
}

static int add_display_components(struct device *dev,
                                  struct component_match **matchptr)
{
        struct device *mdp_dev;
        int ret;

        /*
         * MDP5/DPU based devices don't have a flat hierarchy. There is a top
         * level parent: MDSS, and children: MDP5/DPU, DSI, HDMI, eDP etc.
         * Populate the children devices, find the MDP5/DPU node, and then add
         * the interfaces to our components list.
         */
        if (of_device_is_compatible(dev->of_node, "qcom,mdss") ||
            of_device_is_compatible(dev->of_node, "qcom,sdm845-mdss") ||
            of_device_is_compatible(dev->of_node, "qcom,sc7180-mdss")) {
                ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
                if (ret) {
                        DRM_DEV_ERROR(dev, "failed to populate children devices\n");
                        return ret;
                }

                mdp_dev = device_find_child(dev, NULL, compare_name_mdp);
                if (!mdp_dev) {
                        DRM_DEV_ERROR(dev, "failed to find MDSS MDP node\n");
                        of_platform_depopulate(dev);
                        return -ENODEV;
                }

                put_device(mdp_dev);

                /* add the MDP component itself */
                drm_of_component_match_add(dev, matchptr, compare_of,
                                           mdp_dev->of_node);
        } else {
                /* MDP4 */
                mdp_dev = dev;
        }

        ret = add_components_mdp(mdp_dev, matchptr);
        if (ret)
                of_platform_depopulate(dev);

        return ret;
}

/*
 * We don't know what's the best binding to link the gpu with the drm device.
 * Fow now, we just hunt for all the possible gpus that we support, and add them
 * as components.
 */
static const struct of_device_id msm_gpu_match[] = {
        { .compatible = "qcom,adreno" },
        { .compatible = "qcom,adreno-3xx" },
        { .compatible = "amd,imageon" },
        { .compatible = "qcom,kgsl-3d0" },
        { },
};

static int add_gpu_components(struct device *dev,
                              struct component_match **matchptr)
{
        struct device_node *np;

        np = of_find_matching_node(NULL, msm_gpu_match);
        if (!np)
                return 0;

        if (of_device_is_available(np))
                drm_of_component_match_add(dev, matchptr, compare_of, np);

        of_node_put(np);

        return 0;
}

static int msm_drm_bind(struct device *dev)
{
        return msm_drm_init(dev, &msm_driver);
}

static void msm_drm_unbind(struct device *dev)
{
        msm_drm_uninit(dev);
}

static const struct component_master_ops msm_drm_ops = {
        .bind = msm_drm_bind,
        .unbind = msm_drm_unbind,
};

/*
 * Platform driver:
 */

static int msm_pdev_probe(struct platform_device *pdev)
{
        struct component_match *match = NULL;
        int ret;

        if (get_mdp_ver(pdev)) {
                ret = add_display_components(&pdev->dev, &match);
                if (ret)
                        return ret;
        }

        ret = add_gpu_components(&pdev->dev, &match);
        if (ret)
                goto fail;

        /* on all devices that I am aware of, iommu's which can map
         * any address the cpu can see are used:
         */
        ret = dma_set_mask_and_coherent(&pdev->dev, ~0);
        if (ret)
                goto fail;

        ret = component_master_add_with_match(&pdev->dev, &msm_drm_ops, match);
        if (ret)
                goto fail;

        return 0;

fail:
        of_platform_depopulate(&pdev->dev);
        return ret;
}

static int msm_pdev_remove(struct platform_device *pdev)
{
        component_master_del(&pdev->dev, &msm_drm_ops);
        of_platform_depopulate(&pdev->dev);

        return 0;
}

static const struct of_device_id dt_match[] = {
        { .compatible = "qcom,mdp4", .data = (void *)KMS_MDP4 },
        { .compatible = "qcom,mdss", .data = (void *)KMS_MDP5 },
        { .compatible = "qcom,sdm845-mdss", .data = (void *)KMS_DPU },
        { .compatible = "qcom,sc7180-mdss", .data = (void *)KMS_DPU },
        {}
};
MODULE_DEVICE_TABLE(of, dt_match);

static struct platform_driver msm_platform_driver = {
        .probe      = msm_pdev_probe,
        .remove     = msm_pdev_remove,
        .driver     = {
                .name   = "msm",
                .of_match_table = dt_match,
                .pm     = &msm_pm_ops,
        },
};

static int __init msm_drm_register(void)
{
        if (!modeset)
                return -EINVAL;

        DBG("init");
        msm_mdp_register();
        msm_dpu_register();
        msm_dsi_register();
        msm_edp_register();
        msm_hdmi_register();
        adreno_register();
        return platform_driver_register(&msm_platform_driver);
}

static void __exit msm_drm_unregister(void)
{
        DBG("fini");
        platform_driver_unregister(&msm_platform_driver);
        msm_hdmi_unregister();
        adreno_unregister();
        msm_edp_unregister();
        msm_dsi_unregister();
        msm_mdp_unregister();
        msm_dpu_unregister();
}

module_init(msm_drm_register);
module_exit(msm_drm_unregister);

MODULE_AUTHOR("Rob Clark <robdclark@gmail.com");
MODULE_DESCRIPTION("MSM DRM Driver");
MODULE_LICENSE("GPL");