From c90f30812a79abeb9f7f0f78e69d314104b825be Mon Sep 17 00:00:00 2001 From: Steven Price Date: Thu, 22 Aug 2019 10:32:18 +0100 Subject: [PATCH 01/14] drm/panfrost: Add missing check for pfdev->regulator When modifying panfrost_devfreq_target() to support a device without a regulator defined I missed the check on the error path. Let's add it. Reported-by: Dan Carpenter Fixes: e21dd290881b ("drm/panfrost: Enable devfreq to work without regulator") Signed-off-by: Steven Price Signed-off-by: Rob Herring Link: https://patchwork.freedesktop.org/patch/msgid/20190822093218.26014-1-steven.price@arm.com --- drivers/gpu/drm/panfrost/panfrost_devfreq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c index 710d903f8e0d..a1f5fa6a742a 100644 --- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c +++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c @@ -53,8 +53,10 @@ static int panfrost_devfreq_target(struct device *dev, unsigned long *freq, if (err) { dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate, err); - regulator_set_voltage(pfdev->regulator, pfdev->devfreq.cur_volt, - pfdev->devfreq.cur_volt); + if (pfdev->regulator) + regulator_set_voltage(pfdev->regulator, + pfdev->devfreq.cur_volt, + pfdev->devfreq.cur_volt); return err; } From aebe8c22a9121e89cdd5c725f2ebed1ee237ff16 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Thu, 22 Aug 2019 21:12:09 -0500 Subject: [PATCH 02/14] drm/panfrost: Fix possible suspend in panfrost_remove Calls to panfrost_device_fini() access the h/w, but we already done a pm_runtime_put_sync_autosuspend() beforehand. This only works if the autosuspend delay is long enough. A 0ms delay will hang the system when removing the device. Fix this by moving the pm_runtime_put_sync_suspend() after the panfrost_device_fini() call. Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Reviewed-by: Steven Price Acked-by: Alyssa Rosenzweig Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-2-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_drv.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index 44a558c6e17e..d74442d71048 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -570,11 +570,13 @@ static int panfrost_remove(struct platform_device *pdev) drm_dev_unregister(ddev); panfrost_gem_shrinker_cleanup(ddev); + pm_runtime_get_sync(pfdev->dev); - pm_runtime_put_sync_autosuspend(pfdev->dev); - pm_runtime_disable(pfdev->dev); panfrost_devfreq_fini(pfdev); panfrost_device_fini(pfdev); + pm_runtime_put_sync_suspend(pfdev->dev); + pm_runtime_disable(pfdev->dev); + drm_dev_put(ddev); return 0; } From fe20d1cc95827e240cfcb21490b05ef38518ee4e Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Thu, 22 Aug 2019 21:12:12 -0500 Subject: [PATCH 03/14] drm/shmem: Do dma_unmap_sg before purging pages Calling dma_unmap_sg() in drm_gem_shmem_free_object() is too late if the backing pages have already been released by the shrinker. The result is the following abort: Unable to handle kernel paging request at virtual address ffff8000098ed000 Mem abort info: ESR = 0x96000147 Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000147 CM = 1, WnR = 1 swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000002f51000 [ffff8000098ed000] pgd=00000000401f8003, pud=00000000401f7003, pmd=00000000401b1003, pte=00e80000098ed712 Internal error: Oops: 96000147 [#1] SMP Modules linked in: panfrost gpu_sched CPU: 5 PID: 902 Comm: gnome-shell Not tainted 5.3.0-rc1+ #95 Hardware name: 96boards Rock960 (DT) pstate: 40000005 (nZcv daif -PAN -UAO) pc : __dma_inv_area+0x40/0x58 lr : arch_sync_dma_for_cpu+0x28/0x30 sp : ffff00001321ba30 x29: ffff00001321ba30 x28: ffff00001321bd08 x27: 0000000000000000 x26: 0000000000000009 x25: 0000ffffc1f86170 x24: 0000000000000000 x23: 0000000000000000 x22: 0000000000000000 x21: 0000000000021000 x20: ffff80003bb2d810 x19: 00000000098ed000 x18: 0000000000000000 x17: 0000000000000000 x16: ffff800023fd9480 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 00000000fffb9fff x10: 0000000000000000 x9 : 0000000000000000 x8 : ffff800023fd9c18 x7 : 0000000000000000 x6 : 00000000ffffffff x5 : 0000000000000000 x4 : 0000000000021000 Purging 5693440 bytes x3 : 000000000000003f x2 : 0000000000000040 x1 : ffff80000990e000 x0 : ffff8000098ed000 Call trace: __dma_inv_area+0x40/0x58 dma_direct_sync_single_for_cpu+0x7c/0x80 dma_direct_unmap_page+0x80/0x88 dma_direct_unmap_sg+0x54/0x80 drm_gem_shmem_free_object+0xfc/0x108 panfrost_gem_free_object+0x118/0x128 [panfrost] drm_gem_object_free+0x18/0x90 drm_gem_object_put_unlocked+0x58/0x80 drm_gem_object_handle_put_unlocked+0x64/0xb0 drm_gem_object_release_handle+0x70/0x98 drm_gem_handle_delete+0x64/0xb0 drm_gem_close_ioctl+0x28/0x38 drm_ioctl_kernel+0xb8/0x110 drm_ioctl+0x244/0x3f0 do_vfs_ioctl+0xbc/0x910 ksys_ioctl+0x78/0xa8 __arm64_sys_ioctl+0x1c/0x28 el0_svc_common.constprop.0+0x88/0x150 el0_svc_handler+0x28/0x78 el0_svc+0x8/0xc Code: 8a230000 54000060 d50b7e20 14000002 (d5087620) Fixes: 17acb9f35ed7 ("drm/shmem: Add madvise state and purge helpers") Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Sean Paul Cc: David Airlie Cc: Daniel Vetter Reviewed-by: Steven Price Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-5-robh@kernel.org --- drivers/gpu/drm/drm_gem_shmem_helper.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index df8f2c8adb2b..5423ec56b535 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -390,6 +390,12 @@ void drm_gem_shmem_purge_locked(struct drm_gem_object *obj) WARN_ON(!drm_gem_shmem_is_purgeable(shmem)); + dma_unmap_sg(obj->dev->dev, shmem->sgt->sgl, + shmem->sgt->nents, DMA_BIDIRECTIONAL); + sg_free_table(shmem->sgt); + kfree(shmem->sgt); + shmem->sgt = NULL; + drm_gem_shmem_put_pages_locked(shmem); shmem->madv = -1; From edbd7f318cd66cec4588a28ba6985b014456dbca Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Thu, 22 Aug 2019 21:12:13 -0500 Subject: [PATCH 04/14] drm/shmem: Use mutex_trylock in drm_gem_shmem_purge Lockdep reports a circular locking dependency with pages_lock taken in the shrinker callback. The deadlock can't actually happen with current users at least as a BO will never be purgeable when pages_lock is held. To be safe, let's use mutex_trylock() instead and bail if a BO is locked already. WARNING: possible circular locking dependency detected 5.3.0-rc1+ #100 Tainted: G L ------------------------------------------------------ kswapd0/171 is trying to acquire lock: 000000009b9823fd (&shmem->pages_lock){+.+.}, at: drm_gem_shmem_purge+0x20/0x40 but task is already holding lock: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}: fs_reclaim_acquire.part.18+0x34/0x40 fs_reclaim_acquire+0x20/0x28 __kmalloc_node+0x6c/0x4c0 kvmalloc_node+0x38/0xa8 drm_gem_get_pages+0x80/0x1d0 drm_gem_shmem_get_pages+0x58/0xa0 drm_gem_shmem_get_pages_sgt+0x48/0xd0 panfrost_mmu_map+0x38/0xf8 [panfrost] panfrost_gem_open+0xc0/0xe8 [panfrost] drm_gem_handle_create_tail+0xe8/0x198 drm_gem_handle_create+0x3c/0x50 panfrost_gem_create_with_handle+0x70/0xa0 [panfrost] panfrost_ioctl_create_bo+0x48/0x80 [panfrost] drm_ioctl_kernel+0xb8/0x110 drm_ioctl+0x244/0x3f0 do_vfs_ioctl+0xbc/0x910 ksys_ioctl+0x78/0xa8 __arm64_sys_ioctl+0x1c/0x28 el0_svc_common.constprop.0+0x90/0x168 el0_svc_handler+0x28/0x78 el0_svc+0x8/0xc -> #0 (&shmem->pages_lock){+.+.}: __lock_acquire+0xa2c/0x1d70 lock_acquire+0xdc/0x228 __mutex_lock+0x8c/0x800 mutex_lock_nested+0x1c/0x28 drm_gem_shmem_purge+0x20/0x40 panfrost_gem_shrinker_scan+0xc0/0x180 [panfrost] do_shrink_slab+0x208/0x500 shrink_slab+0x10c/0x2c0 shrink_node+0x28c/0x4d8 balance_pgdat+0x2c8/0x570 kswapd+0x22c/0x638 kthread+0x128/0x130 ret_from_fork+0x10/0x18 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&shmem->pages_lock); lock(fs_reclaim); lock(&shmem->pages_lock); *** DEADLOCK *** 3 locks held by kswapd0/171: #0: 00000000f82369b6 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x40 #1: 00000000ceb37808 (shrinker_rwsem){++++}, at: shrink_slab+0xbc/0x2c0 #2: 00000000f31efa81 (&pfdev->shrinker_lock){+.+.}, at: panfrost_gem_shrinker_scan+0x34/0x180 [panfrost] Fixes: 17acb9f35ed7 ("drm/shmem: Add madvise state and purge helpers") Cc: Maarten Lankhorst Cc: Maxime Ripard Cc: Sean Paul Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Reviewed-by: Steven Price Acked-by: Alyssa Rosenzweig Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-6-robh@kernel.org --- drivers/gpu/drm/drm_gem_shmem_helper.c | 7 +++++-- include/drm/drm_gem_shmem_helper.h | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 5423ec56b535..f5918707672f 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -415,13 +415,16 @@ void drm_gem_shmem_purge_locked(struct drm_gem_object *obj) } EXPORT_SYMBOL(drm_gem_shmem_purge_locked); -void drm_gem_shmem_purge(struct drm_gem_object *obj) +bool drm_gem_shmem_purge(struct drm_gem_object *obj) { struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); - mutex_lock(&shmem->pages_lock); + if (!mutex_trylock(&shmem->pages_lock)) + return false; drm_gem_shmem_purge_locked(obj); mutex_unlock(&shmem->pages_lock); + + return true; } EXPORT_SYMBOL(drm_gem_shmem_purge); diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index ce1600fdfc3e..01f514521687 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -134,7 +134,7 @@ static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem } void drm_gem_shmem_purge_locked(struct drm_gem_object *obj); -void drm_gem_shmem_purge(struct drm_gem_object *obj); +bool drm_gem_shmem_purge(struct drm_gem_object *obj); struct drm_gem_shmem_object * drm_gem_shmem_create_with_handle(struct drm_file *file_priv, From 55b9a0549e4303ca43481f9ba2cdfa305277d97d Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Thu, 22 Aug 2019 21:12:14 -0500 Subject: [PATCH 05/14] drm/panfrost: Use mutex_trylock in panfrost_gem_purge Lockdep reports a circular locking dependency with pages_lock taken in the shrinker callback. The deadlock can't actually happen with current users at least as a BO will never be purgeable when pages_lock is held. To be safe, let's use mutex_trylock() instead and bail if a BO is locked already. Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Reviewed-by: Steven Price Acked-by: Alyssa Rosenzweig Link: https://patchwork.freedesktop.org/patch/msgid/20190823021216.5862-7-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c index d191632b6197..458f0fa68111 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem_shrinker.c @@ -36,15 +36,18 @@ panfrost_gem_shrinker_count(struct shrinker *shrinker, struct shrink_control *sc return count; } -static void panfrost_gem_purge(struct drm_gem_object *obj) +static bool panfrost_gem_purge(struct drm_gem_object *obj) { struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); - mutex_lock(&shmem->pages_lock); + + if (!mutex_trylock(&shmem->pages_lock)) + return false; panfrost_mmu_unmap(to_panfrost_bo(obj)); drm_gem_shmem_purge_locked(obj); mutex_unlock(&shmem->pages_lock); + return true; } static unsigned long @@ -61,8 +64,8 @@ panfrost_gem_shrinker_scan(struct shrinker *shrinker, struct shrink_control *sc) list_for_each_entry_safe(shmem, tmp, &pfdev->shrinker_list, madv_list) { if (freed >= sc->nr_to_scan) break; - if (drm_gem_shmem_is_purgeable(shmem)) { - panfrost_gem_purge(&shmem->base); + if (drm_gem_shmem_is_purgeable(shmem) && + panfrost_gem_purge(&shmem->base)) { freed += shmem->base.size >> PAGE_SHIFT; list_del_init(&shmem->madv_list); } From 635430797d3fccb958e929d3911e39cb9c1ea641 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:10 -0500 Subject: [PATCH 06/14] drm/panfrost: Rework runtime PM initialization There's a few issues with the runtime PM initialization. The documentation states pm_runtime_set_active() should be called before pm_runtime_enable(). The pm_runtime_put_autosuspend() could suspend the GPU before panfrost_perfcnt_init() is called which touches the h/w. The autosuspend delay keeps things from breaking. There's no need explicitly power off the GPU only to wake back up with pm_runtime_get_sync(). Just delaying pm_runtime_enable to the end of probe is sufficient. Lets move all the runtime PM calls into the probe() function so they are all in one place and are done after all initialization. Cc: Tomeu Vizoso Cc: Steven Price Cc: David Airlie Cc: Daniel Vetter Acked-by: Alyssa Rosenzweig Signed-off-by: Rob Herring Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-2-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_device.c | 9 --------- drivers/gpu/drm/panfrost/panfrost_drv.c | 10 ++++++---- 2 files changed, 6 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c index 4da71bb56c20..73805210834e 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.c +++ b/drivers/gpu/drm/panfrost/panfrost_device.c @@ -5,7 +5,6 @@ #include #include #include -#include #include #include "panfrost_device.h" @@ -166,14 +165,6 @@ int panfrost_device_init(struct panfrost_device *pfdev) if (err) goto err_out4; - /* runtime PM will wake us up later */ - panfrost_gpu_power_off(pfdev); - - pm_runtime_set_active(pfdev->dev); - pm_runtime_get_sync(pfdev->dev); - pm_runtime_mark_last_busy(pfdev->dev); - pm_runtime_put_autosuspend(pfdev->dev); - err = panfrost_perfcnt_init(pfdev); if (err) goto err_out5; diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c index d74442d71048..bc2ddeb55f5d 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -523,10 +523,6 @@ static int panfrost_probe(struct platform_device *pdev) mutex_init(&pfdev->shrinker_lock); INIT_LIST_HEAD(&pfdev->shrinker_list); - pm_runtime_use_autosuspend(pfdev->dev); - pm_runtime_set_autosuspend_delay(pfdev->dev, 50); /* ~3 frames */ - pm_runtime_enable(pfdev->dev); - err = panfrost_device_init(pfdev); if (err) { if (err != -EPROBE_DEFER) @@ -541,6 +537,12 @@ static int panfrost_probe(struct platform_device *pdev) goto err_out1; } + pm_runtime_set_active(pfdev->dev); + pm_runtime_mark_last_busy(pfdev->dev); + pm_runtime_enable(pfdev->dev); + pm_runtime_set_autosuspend_delay(pfdev->dev, 50); /* ~3 frames */ + pm_runtime_use_autosuspend(pfdev->dev); + /* * Register the DRM device with the core and the connectors with * sysfs From 330bec4b7ccf4a556469cfec2ad695a180e35954 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:11 -0500 Subject: [PATCH 07/14] drm/panfrost: Hold runtime PM reference until jobs complete Doing a pm_runtime_put as soon as a job is submitted is wrong as it should not happen until the job completes. It works currently because we are relying on the autosuspend timeout to keep the h/w enabled. Fixes: f3ba91228e8e ("drm/panfrost: Add initial panfrost driver") Cc: Tomeu Vizoso Cc: Steven Price Cc: Alyssa Rosenzweig Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-3-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_job.c | 39 ++++++++++++++++++------- 1 file changed, 28 insertions(+), 11 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 05c85f45a0de..18bcc9bac6d2 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -150,8 +150,10 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js) if (ret < 0) return; - if (WARN_ON(job_read(pfdev, JS_COMMAND_NEXT(js)))) - goto end; + if (WARN_ON(job_read(pfdev, JS_COMMAND_NEXT(js)))) { + pm_runtime_put_sync_autosuspend(pfdev->dev); + return; + } cfg = panfrost_mmu_as_get(pfdev, &job->file_priv->mmu); @@ -187,10 +189,6 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js) job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START); spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags); - -end: - pm_runtime_mark_last_busy(pfdev->dev); - pm_runtime_put_autosuspend(pfdev->dev); } static void panfrost_acquire_object_fences(struct drm_gem_object **bos, @@ -369,6 +367,7 @@ static void panfrost_job_timedout(struct drm_sched_job *sched_job) struct panfrost_job *job = to_panfrost_job(sched_job); struct panfrost_device *pfdev = job->pfdev; int js = panfrost_job_get_slot(job); + unsigned long flags; int i; /* @@ -394,6 +393,15 @@ static void panfrost_job_timedout(struct drm_sched_job *sched_job) if (sched_job) drm_sched_increase_karma(sched_job); + spin_lock_irqsave(&pfdev->js->job_lock, flags); + for (i = 0; i < NUM_JOB_SLOTS; i++) { + if (pfdev->jobs[i]) { + pm_runtime_put_noidle(pfdev->dev); + pfdev->jobs[i] = NULL; + } + } + spin_unlock_irqrestore(&pfdev->js->job_lock, flags); + /* panfrost_core_dump(pfdev); */ panfrost_devfreq_record_transition(pfdev, js); @@ -450,12 +458,21 @@ static irqreturn_t panfrost_job_irq_handler(int irq, void *data) } if (status & JOB_INT_MASK_DONE(j)) { - struct panfrost_job *job = pfdev->jobs[j]; + struct panfrost_job *job; - pfdev->jobs[j] = NULL; - panfrost_mmu_as_put(pfdev, &job->file_priv->mmu); - panfrost_devfreq_record_transition(pfdev, j); - dma_fence_signal(job->done_fence); + spin_lock(&pfdev->js->job_lock); + job = pfdev->jobs[j]; + /* Only NULL if job timeout occurred */ + if (job) { + pfdev->jobs[j] = NULL; + + panfrost_mmu_as_put(pfdev, &job->file_priv->mmu); + panfrost_devfreq_record_transition(pfdev, j); + + dma_fence_signal_locked(job->done_fence); + pm_runtime_put_autosuspend(pfdev->dev); + } + spin_unlock(&pfdev->js->job_lock); } status &= ~mask; From e316f08f1abf5f1116118e25dce7bc3e9ab03246 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:12 -0500 Subject: [PATCH 08/14] drm/panfrost: Remove unnecessary mmu->lock mutex There's no need to serialize io-pgtable calls and the as_lock is sufficient to serialize flush operations, so we can remove the per page table lock. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Suggested-by: Robin Murphy Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-4-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_device.h | 1 - drivers/gpu/drm/panfrost/panfrost_mmu.c | 9 --------- 2 files changed, 10 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index f503c566e99f..b7fa08ed3a23 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -104,7 +104,6 @@ struct panfrost_device { struct panfrost_mmu { struct io_pgtable_cfg pgtbl_cfg; struct io_pgtable_ops *pgtbl_ops; - struct mutex lock; int as; atomic_t as_count; struct list_head list; diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 842bdd7cf6be..3a8bcfa7e7b6 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -228,8 +228,6 @@ static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, struct io_pgtable_ops *ops = mmu->pgtbl_ops; u64 start_iova = iova; - mutex_lock(&mmu->lock); - for_each_sg(sgt->sgl, sgl, sgt->nents, count) { unsigned long paddr = sg_dma_address(sgl); size_t len = sg_dma_len(sgl); @@ -249,8 +247,6 @@ static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, mmu_hw_do_operation(pfdev, mmu, start_iova, iova - start_iova, AS_COMMAND_FLUSH_PT); - mutex_unlock(&mmu->lock); - return 0; } @@ -304,8 +300,6 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) if (ret < 0) return; - mutex_lock(&bo->mmu->lock); - while (unmapped_len < len) { size_t unmapped_page; size_t pgsize = get_pgsize(iova, len - unmapped_len); @@ -321,8 +315,6 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) mmu_hw_do_operation(pfdev, bo->mmu, bo->node.start << PAGE_SHIFT, bo->node.size << PAGE_SHIFT, AS_COMMAND_FLUSH_PT); - mutex_unlock(&bo->mmu->lock); - pm_runtime_mark_last_busy(pfdev->dev); pm_runtime_put_autosuspend(pfdev->dev); bo->is_mapped = false; @@ -356,7 +348,6 @@ int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv) struct panfrost_mmu *mmu = &priv->mmu; struct panfrost_device *pfdev = priv->pfdev; - mutex_init(&mmu->lock); INIT_LIST_HEAD(&mmu->list); mmu->as = -1; From ec7eba47da867e1dd0ff7d442a8717d70c064658 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:13 -0500 Subject: [PATCH 09/14] drm/panfrost: Rework page table flushing and runtime PM interaction There is no point in resuming the h/w just to do flush operations and doing so takes several locks which cause lockdep issues with the shrinker. Rework the flush operations to only happen when the h/w is already awake. This avoids taking any locks associated with resuming which trigger lockdep warnings. Fixes: 013b65101315 ("drm/panfrost: Add madvise and shrinker support") Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-5-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 38 ++++++++++++------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 3a8bcfa7e7b6..2204e60f7808 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -220,6 +220,22 @@ static size_t get_pgsize(u64 addr, size_t size) return SZ_2M; } +void panfrost_mmu_flush_range(struct panfrost_device *pfdev, + struct panfrost_mmu *mmu, + u64 iova, size_t size) +{ + if (mmu->as < 0) + return; + + pm_runtime_get_noresume(pfdev->dev); + + /* Flush the PTs only if we're already awake */ + if (pm_runtime_active(pfdev->dev)) + mmu_hw_do_operation(pfdev, mmu, iova, size, AS_COMMAND_FLUSH_PT); + + pm_runtime_put_sync_autosuspend(pfdev->dev); +} + static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, u64 iova, int prot, struct sg_table *sgt) { @@ -244,8 +260,7 @@ static int mmu_map_sg(struct panfrost_device *pfdev, struct panfrost_mmu *mmu, } } - mmu_hw_do_operation(pfdev, mmu, start_iova, iova - start_iova, - AS_COMMAND_FLUSH_PT); + panfrost_mmu_flush_range(pfdev, mmu, start_iova, iova - start_iova); return 0; } @@ -255,7 +270,6 @@ int panfrost_mmu_map(struct panfrost_gem_object *bo) struct drm_gem_object *obj = &bo->base.base; struct panfrost_device *pfdev = to_panfrost_device(obj->dev); struct sg_table *sgt; - int ret; int prot = IOMMU_READ | IOMMU_WRITE; if (WARN_ON(bo->is_mapped)) @@ -268,14 +282,7 @@ int panfrost_mmu_map(struct panfrost_gem_object *bo) if (WARN_ON(IS_ERR(sgt))) return PTR_ERR(sgt); - ret = pm_runtime_get_sync(pfdev->dev); - if (ret < 0) - return ret; - mmu_map_sg(pfdev, bo->mmu, bo->node.start << PAGE_SHIFT, prot, sgt); - - pm_runtime_mark_last_busy(pfdev->dev); - pm_runtime_put_autosuspend(pfdev->dev); bo->is_mapped = true; return 0; @@ -289,17 +296,12 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) u64 iova = bo->node.start << PAGE_SHIFT; size_t len = bo->node.size << PAGE_SHIFT; size_t unmapped_len = 0; - int ret; if (WARN_ON(!bo->is_mapped)) return; dev_dbg(pfdev->dev, "unmap: as=%d, iova=%llx, len=%zx", bo->mmu->as, iova, len); - ret = pm_runtime_get_sync(pfdev->dev); - if (ret < 0) - return; - while (unmapped_len < len) { size_t unmapped_page; size_t pgsize = get_pgsize(iova, len - unmapped_len); @@ -312,11 +314,7 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) unmapped_len += pgsize; } - mmu_hw_do_operation(pfdev, bo->mmu, bo->node.start << PAGE_SHIFT, - bo->node.size << PAGE_SHIFT, AS_COMMAND_FLUSH_PT); - - pm_runtime_mark_last_busy(pfdev->dev); - pm_runtime_put_autosuspend(pfdev->dev); + panfrost_mmu_flush_range(pfdev, bo->mmu, bo->node.start << PAGE_SHIFT, len); bo->is_mapped = false; } From 86df65f39b009e00cf2826eac72c5a969b878065 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:14 -0500 Subject: [PATCH 10/14] drm/panfrost: Split mmu_hw_do_operation into locked and unlocked version In preparation to call mmu_hw_do_operation with the as_lock already held, Add a mmu_hw_do_operation_locked function. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-6-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 26 ++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 2204e60f7808..3407b00d0a3a 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -80,19 +80,11 @@ static void lock_region(struct panfrost_device *pfdev, u32 as_nr, } -static int mmu_hw_do_operation(struct panfrost_device *pfdev, - struct panfrost_mmu *mmu, - u64 iova, size_t size, u32 op) +static int mmu_hw_do_operation_locked(struct panfrost_device *pfdev, int as_nr, + u64 iova, size_t size, u32 op) { - int ret, as_nr; - - spin_lock(&pfdev->as_lock); - as_nr = mmu->as; - - if (as_nr < 0) { - spin_unlock(&pfdev->as_lock); + if (as_nr < 0) return 0; - } if (op != AS_COMMAND_UNLOCK) lock_region(pfdev, as_nr, iova, size); @@ -101,10 +93,18 @@ static int mmu_hw_do_operation(struct panfrost_device *pfdev, write_cmd(pfdev, as_nr, op); /* Wait for the flush to complete */ - ret = wait_ready(pfdev, as_nr); + return wait_ready(pfdev, as_nr); +} +static int mmu_hw_do_operation(struct panfrost_device *pfdev, + struct panfrost_mmu *mmu, + u64 iova, size_t size, u32 op) +{ + int ret; + + spin_lock(&pfdev->as_lock); + ret = mmu_hw_do_operation_locked(pfdev, mmu->as, iova, size, op); spin_unlock(&pfdev->as_lock); - return ret; } From 5924d40958dfc2b8996fbf788a9d58e411a6db71 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:15 -0500 Subject: [PATCH 11/14] drm/panfrost: Add cache/TLB flush before switching address space It's not entirely clear if this is required, but add a flush of GPU caches and TLBs before we change an address space to new page tables. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-7-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 3407b00d0a3a..d1ebde3327fe 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -115,6 +115,8 @@ static void panfrost_mmu_enable(struct panfrost_device *pfdev, struct panfrost_m u64 transtab = cfg->arm_mali_lpae_cfg.transtab; u64 memattr = cfg->arm_mali_lpae_cfg.memattr; + mmu_hw_do_operation_locked(pfdev, as_nr, 0, ~0UL, AS_COMMAND_FLUSH_MEM); + mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), transtab & 0xffffffffUL); mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), transtab >> 32); From 62f1089f3cbe7d99ced92bf96a8158813b75e5e8 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:16 -0500 Subject: [PATCH 12/14] drm/panfrost: Flush and disable address space when freeing page tables Currently, page tables are freed without disabling the address space first. This probably is fine as we'll switch to new page tables when the address space is allocated again and runtime PM suspend will reset the GPU clearing the registers. However, it's better to clean up after ourselves. There is also a problem that we could be accessing the h/w in tlb_inv_context() when suspended. Rework the disable code to make sure we flush caches/TLBs and disable the address space before freeing the page tables if we are not suspended. As the tlb_inv_context() hook is only called when freeing the page tables and we do a flush before disabling the AS, lets remove the flush from tlb_inv_context and avoid any runtime PM issues. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Robin Murphy Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-8-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index d1ebde3327fe..387d830cb7cf 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -129,8 +129,10 @@ static void panfrost_mmu_enable(struct panfrost_device *pfdev, struct panfrost_m write_cmd(pfdev, as_nr, AS_COMMAND_UPDATE); } -static void mmu_disable(struct panfrost_device *pfdev, u32 as_nr) +static void panfrost_mmu_disable(struct panfrost_device *pfdev, u32 as_nr) { + mmu_hw_do_operation_locked(pfdev, as_nr, 0, ~0UL, AS_COMMAND_FLUSH_MEM); + mmu_write(pfdev, AS_TRANSTAB_LO(as_nr), 0); mmu_write(pfdev, AS_TRANSTAB_HI(as_nr), 0); @@ -321,11 +323,7 @@ void panfrost_mmu_unmap(struct panfrost_gem_object *bo) } static void mmu_tlb_inv_context_s1(void *cookie) -{ - struct panfrost_file_priv *priv = cookie; - - mmu_hw_do_operation(priv->pfdev, &priv->mmu, 0, ~0UL, AS_COMMAND_FLUSH_MEM); -} +{} static void mmu_tlb_inv_range_nosync(unsigned long iova, size_t size, size_t granule, bool leaf, void *cookie) @@ -374,6 +372,11 @@ void panfrost_mmu_pgtable_free(struct panfrost_file_priv *priv) spin_lock(&pfdev->as_lock); if (mmu->as >= 0) { + pm_runtime_get_noresume(pfdev->dev); + if (pm_runtime_active(pfdev->dev)) + panfrost_mmu_disable(pfdev, mmu->as); + pm_runtime_put_autosuspend(pfdev->dev); + clear_bit(mmu->as, &pfdev->as_alloc_mask); clear_bit(mmu->as, &pfdev->as_in_use_mask); list_del(&mmu->list); @@ -618,5 +621,4 @@ int panfrost_mmu_init(struct panfrost_device *pfdev) void panfrost_mmu_fini(struct panfrost_device *pfdev) { mmu_write(pfdev, MMU_INT_MASK, 0); - mmu_disable(pfdev, 0); } From 45d0dbd15a3b89ced53e058bc71b751e6473b664 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Mon, 26 Aug 2019 17:33:17 -0500 Subject: [PATCH 13/14] drm/panfrost: Remove unnecessary hwaccess_lock spin_lock With the introduction of the as_lock to serialize address space registers, the hwaccess_lock is only used within the job code and is not protecting anything. panfrost_job_hw_submit() only accesses registers for 1 job slot and it's already serialized by drm_sched. Fixes: 7282f7645d06 ("drm/panfrost: Implement per FD address spaces") Cc: Tomeu Vizoso Cc: David Airlie Cc: Daniel Vetter Signed-off-by: Rob Herring Acked-by: Alyssa Rosenzweig Reviewed-by: Steven Price Link: https://patchwork.freedesktop.org/patch/msgid/20190826223317.28509-9-robh@kernel.org --- drivers/gpu/drm/panfrost/panfrost_device.c | 1 - drivers/gpu/drm/panfrost/panfrost_device.h | 2 -- drivers/gpu/drm/panfrost/panfrost_job.c | 4 ---- 3 files changed, 7 deletions(-) diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c index 73805210834e..46b0b02e4289 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.c +++ b/drivers/gpu/drm/panfrost/panfrost_device.c @@ -124,7 +124,6 @@ int panfrost_device_init(struct panfrost_device *pfdev) INIT_LIST_HEAD(&pfdev->scheduled_jobs); INIT_LIST_HEAD(&pfdev->as_lru_list); - spin_lock_init(&pfdev->hwaccess_lock); spin_lock_init(&pfdev->as_lock); err = panfrost_clk_init(pfdev); diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h index b7fa08ed3a23..9c39b9794811 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.h +++ b/drivers/gpu/drm/panfrost/panfrost_device.h @@ -63,8 +63,6 @@ struct panfrost_device { struct drm_device *ddev; struct platform_device *pdev; - spinlock_t hwaccess_lock; - void __iomem *iomem; struct clk *clock; struct clk *bus_clock; diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c index 18bcc9bac6d2..a58551668d9a 100644 --- a/drivers/gpu/drm/panfrost/panfrost_job.c +++ b/drivers/gpu/drm/panfrost/panfrost_job.c @@ -141,7 +141,6 @@ static void panfrost_job_write_affinity(struct panfrost_device *pfdev, static void panfrost_job_hw_submit(struct panfrost_job *job, int js) { struct panfrost_device *pfdev = job->pfdev; - unsigned long flags; u32 cfg; u64 jc_head = job->jc; int ret; @@ -158,7 +157,6 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js) cfg = panfrost_mmu_as_get(pfdev, &job->file_priv->mmu); panfrost_devfreq_record_transition(pfdev, js); - spin_lock_irqsave(&pfdev->hwaccess_lock, flags); job_write(pfdev, JS_HEAD_NEXT_LO(js), jc_head & 0xFFFFFFFF); job_write(pfdev, JS_HEAD_NEXT_HI(js), jc_head >> 32); @@ -187,8 +185,6 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js) job, js, jc_head); job_write(pfdev, JS_COMMAND_NEXT(js), JS_COMMAND_START); - - spin_unlock_irqrestore(&pfdev->hwaccess_lock, flags); } static void panfrost_acquire_object_fences(struct drm_gem_object **bos, From 88537ddbbe4c755e193aa220a306395edf08a4cf Mon Sep 17 00:00:00 2001 From: Linus Walleij Date: Tue, 3 Sep 2019 19:08:04 +0200 Subject: [PATCH 14/14] drm/mcde: Fix DSI transfers There were bugs in the DSI transfer (read and write) function as it was only tested with displays ever needing a single byte to be written. Fixed it up and tested so we can now write messages of up to 16 bytes and read up to 4 bytes from the display. Tested with a Sony ACX424AKP display: this display now self- identifies and can control backlight in command mode. Reported-by: kbuild test robot Fixes: 5fc537bfd000 ("drm/mcde: Add new driver for ST-Ericsson MCDE") Reviewed-by: Stephan Gerhold Signed-off-by: Linus Walleij Link: https://patchwork.freedesktop.org/patch/msgid/20190903170804.17053-1-linus.walleij@linaro.org --- drivers/gpu/drm/mcde/mcde_dsi.c | 68 ++++++++++++++++++++++----------- 1 file changed, 46 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/mcde/mcde_dsi.c b/drivers/gpu/drm/mcde/mcde_dsi.c index 07f7090d08b3..f9c9e32b299c 100644 --- a/drivers/gpu/drm/mcde/mcde_dsi.c +++ b/drivers/gpu/drm/mcde/mcde_dsi.c @@ -178,22 +178,26 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host, const u32 loop_delay_us = 10; /* us */ const u8 *tx = msg->tx_buf; u32 loop_counter; - size_t txlen; + size_t txlen = msg->tx_len; + size_t rxlen = msg->rx_len; u32 val; int ret; int i; - txlen = msg->tx_len; - if (txlen > 12) { + if (txlen > 16) { dev_err(d->dev, - "dunno how to write more than 12 bytes yet\n"); + "dunno how to write more than 16 bytes yet\n"); + return -EIO; + } + if (rxlen > 4) { + dev_err(d->dev, + "dunno how to read more than 4 bytes yet\n"); return -EIO; } dev_dbg(d->dev, - "message to channel %d, %zd bytes", - msg->channel, - txlen); + "message to channel %d, write %zd bytes read %zd bytes\n", + msg->channel, txlen, rxlen); /* Command "nature" */ if (MCDE_DSI_HOST_IS_READ(msg->type)) @@ -210,9 +214,7 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host, if (mipi_dsi_packet_format_is_long(msg->type)) val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LONGNOTSHORT; val |= 0 << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_ID_SHIFT; - /* Add one to the length for the MIPI DCS command */ - val |= txlen - << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT; + val |= txlen << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_SIZE_SHIFT; val |= DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_LP_EN; val |= msg->type << DSI_DIRECT_CMD_MAIN_SETTINGS_CMD_HEAD_SHIFT; writel(val, d->regs + DSI_DIRECT_CMD_MAIN_SETTINGS); @@ -249,17 +251,36 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host, writel(1, d->regs + DSI_DIRECT_CMD_SEND); loop_counter = 1000 * 1000 / loop_delay_us; - while (!(readl(d->regs + DSI_DIRECT_CMD_STS) & - DSI_DIRECT_CMD_STS_WRITE_COMPLETED) - && --loop_counter) - usleep_range(loop_delay_us, (loop_delay_us * 3) / 2); + if (MCDE_DSI_HOST_IS_READ(msg->type)) { + /* Read command */ + while (!(readl(d->regs + DSI_DIRECT_CMD_STS) & + (DSI_DIRECT_CMD_STS_READ_COMPLETED | + DSI_DIRECT_CMD_STS_READ_COMPLETED_WITH_ERR)) + && --loop_counter) + usleep_range(loop_delay_us, (loop_delay_us * 3) / 2); + if (!loop_counter) { + dev_err(d->dev, "DSI read timeout!\n"); + return -ETIME; + } + } else { + /* Writing only */ + while (!(readl(d->regs + DSI_DIRECT_CMD_STS) & + DSI_DIRECT_CMD_STS_WRITE_COMPLETED) + && --loop_counter) + usleep_range(loop_delay_us, (loop_delay_us * 3) / 2); - if (!loop_counter) { - dev_err(d->dev, "DSI write timeout!\n"); - return -ETIME; + if (!loop_counter) { + dev_err(d->dev, "DSI write timeout!\n"); + return -ETIME; + } } val = readl(d->regs + DSI_DIRECT_CMD_STS); + if (val & DSI_DIRECT_CMD_STS_READ_COMPLETED_WITH_ERR) { + dev_err(d->dev, "read completed with error\n"); + writel(1, d->regs + DSI_DIRECT_CMD_RD_INIT); + return -EIO; + } if (val & DSI_DIRECT_CMD_STS_ACKNOWLEDGE_WITH_ERR_RECEIVED) { val >>= DSI_DIRECT_CMD_STS_ACK_VAL_SHIFT; dev_err(d->dev, "error during transmission: %04x\n", @@ -269,10 +290,7 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host, if (!MCDE_DSI_HOST_IS_READ(msg->type)) { /* Return number of bytes written */ - if (mipi_dsi_packet_format_is_long(msg->type)) - ret = 4 + txlen; - else - ret = 4; + ret = txlen; } else { /* OK this is a read command, get the response */ u32 rdsz; @@ -282,7 +300,13 @@ static ssize_t mcde_dsi_host_transfer(struct mipi_dsi_host *host, rdsz = readl(d->regs + DSI_DIRECT_CMD_RD_PROPERTY); rdsz &= DSI_DIRECT_CMD_RD_PROPERTY_RD_SIZE_MASK; rddat = readl(d->regs + DSI_DIRECT_CMD_RDDAT); - for (i = 0; i < 4 && i < rdsz; i++) + if (rdsz < rxlen) { + dev_err(d->dev, "read error, requested %zd got %d\n", + rxlen, rdsz); + return -EIO; + } + /* FIXME: read more than 4 bytes */ + for (i = 0; i < 4 && i < rxlen; i++) rx[i] = (rddat >> (i * 8)) & 0xff; ret = rdsz; }