Re: [PATCH 5/7] drm/vc4: Disable V3D interactions if the v3d component didn't probe.

Hi,

On Wed, 2019-02-20 at 13:03 -0800, Eric Anholt wrote:

One might want to use the VC4 display stack without using Mesa. Similar to the debugfs fixes for not having all of the possible display bits enabled, make sure you can't oops in vc4 if v3d isn't enabled.

See a comment below.

Signed-off-by: Eric Anholt eric@anholt.net

drivers/gpu/drm/vc4/vc4_drv.c | 11 +++++++++++ drivers/gpu/drm/vc4/vc4_gem.c | 10 ++++++++++ drivers/gpu/drm/vc4/vc4_irq.c | 9 +++++++++ drivers/gpu/drm/vc4/vc4_perfmon.c | 18 ++++++++++++++++++ 4 files changed, 48 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index 1927d1b756f5..de1d0ce11831 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -72,6 +72,9 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data, if (args->pad != 0) return -EINVAL;

• if (!vc4->v3d)

• return -EINVAL;
  

• switch (args->param) { case DRM_VC4_PARAM_V3D_IDENT0: ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev);

@@ -251,6 +254,7 @@ static int vc4_drm_bind(struct device *dev) struct platform_device *pdev = to_platform_device(dev); struct drm_device *drm; struct vc4_dev *vc4;

• struct device_node *node; int ret = 0;

  dev->coherent_dma_mask = DMA_BIT_MASK(32);

@@ -259,6 +263,13 @@ static int vc4_drm_bind(struct device *dev) if (!vc4) return -ENOMEM;

• /* If VC4 V3D is missing, don't advertise render nodes. */
• node = of_find_compatible_node(NULL, NULL, "brcm,bcm2835-v3d");

It looks like we support more compatibles than this one, so it could be worth having a separate helper to check if we can find a v3d-compatible node. It could certainly reuse the platform driver's of_match_table;

With that fixed, this is: Reviewed-by: Paul Kocialkowski paul.kocialkowski@bootlin.com

Cheers,

Paul

• if (node)

• of_node_put(node);
  

• else

• vc4_drm_driver.driver_features &= ~DRIVER_RENDER;
  

• drm = drm_dev_alloc(&vc4_drm_driver, dev); if (IS_ERR(drm)) return PTR_ERR(drm);

diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c index 5ee5bf7fedf7..8d816e5ed762 100644 --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -74,6 +74,11 @@ vc4_get_hang_state_ioctl(struct drm_device *dev, void *data, u32 i; int ret = 0;

• if (!vc4->v3d) {

• DRM_DEBUG("VC4_GET_HANG_STATE with no VC4 V3D probed\n");
  

• return -EINVAL;
  

• }
• spin_lock_irqsave(&vc4->job_lock, irqflags); kernel_state = vc4->hang_state; if (!kernel_state) {

@@ -1124,6 +1129,11 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data, struct dma_fence *in_fence; int ret = 0;

• if (!vc4->v3d) {

• DRM_DEBUG("VC4_SUBMIT_CL with no VC4 V3D probed\n");
  

• return -EINVAL;
  

• }
• if ((args->flags & ~(VC4_SUBMIT_CL_USE_CLEAR_COLOR | VC4_SUBMIT_CL_FIXED_RCL_ORDER | VC4_SUBMIT_CL_RCL_ORDER_INCREASING_X |

diff --git a/drivers/gpu/drm/vc4/vc4_irq.c b/drivers/gpu/drm/vc4/vc4_irq.c index 4cd2ccfe15f4..ffd0a4388752 100644 --- a/drivers/gpu/drm/vc4/vc4_irq.c +++ b/drivers/gpu/drm/vc4/vc4_irq.c @@ -229,6 +229,9 @@ vc4_irq_preinstall(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev);

• if (!vc4->v3d)

• return;
  

• init_waitqueue_head(&vc4->job_wait_queue); INIT_WORK(&vc4->overflow_mem_work, vc4_overflow_mem_work);

@@ -243,6 +246,9 @@ vc4_irq_postinstall(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev);

• if (!vc4->v3d)

• return 0;
  

• /* Enable both the render done and out of memory interrupts. */ V3D_WRITE(V3D_INTENA, V3D_DRIVER_IRQS);

@@ -254,6 +260,9 @@ vc4_irq_uninstall(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev);

• if (!vc4->v3d)

• return;
  

• /* Disable sending interrupts for our driver's IRQs. */ V3D_WRITE(V3D_INTDIS, V3D_DRIVER_IRQS);

diff --git a/drivers/gpu/drm/vc4/vc4_perfmon.c b/drivers/gpu/drm/vc4/vc4_perfmon.c index 495150415020..6562d3d30b20 100644 --- a/drivers/gpu/drm/vc4/vc4_perfmon.c +++ b/drivers/gpu/drm/vc4/vc4_perfmon.c @@ -100,12 +100,18 @@ void vc4_perfmon_close_file(struct vc4_file *vc4file) int vc4_perfmon_create_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) {

• struct vc4_dev *vc4 = to_vc4_dev(dev); struct vc4_file *vc4file = file_priv->driver_priv; struct drm_vc4_perfmon_create *req = data; struct vc4_perfmon *perfmon; unsigned int i; int ret;

• if (!vc4->v3d) {

• DRM_DEBUG("Creating perfmon no VC4 V3D probed\n");
  

• return -EINVAL;
  

• }

• /* Number of monitored counters cannot exceed HW limits. */ if (req->ncounters > DRM_VC4_MAX_PERF_COUNTERS || !req->ncounters)

@@ -146,10 +152,16 @@ int vc4_perfmon_create_ioctl(struct drm_device *dev, void *data, int vc4_perfmon_destroy_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) {

• struct vc4_dev *vc4 = to_vc4_dev(dev); struct vc4_file *vc4file = file_priv->driver_priv; struct drm_vc4_perfmon_destroy *req = data; struct vc4_perfmon *perfmon;

• if (!vc4->v3d) {

• DRM_DEBUG("Destroying perfmon no VC4 V3D probed\n");
  

• return -EINVAL;
  

• }

• mutex_lock(&vc4file->perfmon.lock); perfmon = idr_remove(&vc4file->perfmon.idr, req->id); mutex_unlock(&vc4file->perfmon.lock);

@@ -164,11 +176,17 @@ int vc4_perfmon_destroy_ioctl(struct drm_device *dev, void *data, int vc4_perfmon_get_values_ioctl(struct drm_device *dev, void *data, struct drm_file *file_priv) {

• struct vc4_dev *vc4 = to_vc4_dev(dev); struct vc4_file *vc4file = file_priv->driver_priv; struct drm_vc4_perfmon_get_values *req = data; struct vc4_perfmon *perfmon; int ret;

• if (!vc4->v3d) {

• DRM_DEBUG("Getting perfmon no VC4 V3D probed\n");
  

• return -EINVAL;
  

• }

• mutex_lock(&vc4file->perfmon.lock); perfmon = idr_find(&vc4file->perfmon.idr, req->id); vc4_perfmon_get(perfmon);