| Message ID | 20180914092438.21492-1-l.stach@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/etnaviv: add DMA configuration for etnaviv platform device | expand |
Hi, On Fri, Sep 14, 2018 at 11:24:38AM +0200, Lucas Stach wrote: > The etnaviv device is a virtual device backing the DRM device, which may > drive multiple hardware GPU core devies. As most of the dma-mapping handling > is done through the virtual device, we need to make sure that a proper DMA > setup is in place. The easiest way to get a reasonable configuration is > to let the virtual device share the DMA configuration with one of the GPU > devices, so call of_dma_configure() with the right parameters manually. > > This assumes that all etnaviv driven GPU devices in the system share the > same DMA configuration. If we ever encounter a SoC where the GPUs are on > busses with different offsets or behind different IOMMUs that will require > much deeper changes to the driver, as we would need to implement etnaviv > specific versions of most of the DRM helper functions. > > For now we should be fine with this solution. This works on GC7000, thanks! Tested-By: Guido Günther <agx@sigxcpu.org> > > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> > --- > drivers/gpu/drm/etnaviv/etnaviv_drv.c | 27 +++++++++++++++++++++------ > 1 file changed, 21 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c > index 9b2720b41571..83c1f46670bf 100644 > --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c > +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c > @@ -592,8 +592,6 @@ static int etnaviv_pdev_probe(struct platform_device *pdev) > struct device *dev = &pdev->dev; > struct component_match *match = NULL; > > - dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32)); > - > if (!dev->platform_data) { > struct device_node *core_node; > > @@ -655,13 +653,30 @@ static int __init etnaviv_init(void) > for_each_compatible_node(np, NULL, "vivante,gc") { > if (!of_device_is_available(np)) > continue; > - pdev = platform_device_register_simple("etnaviv", -1, > - NULL, 0); > - if (IS_ERR(pdev)) { > - ret = PTR_ERR(pdev); > + > + pdev = platform_device_alloc("etnaviv", -1); > + if (!pdev) { > + ret = -ENOMEM; > + of_node_put(np); > + goto unregister_platform_driver; > + } > + pdev->dev.coherent_dma_mask = DMA_BIT_MASK(40); > + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; > + > + /* > + * Apply the same DMA configuration to the virtual etnaviv > + * device as the GPU we found. This assumes that all Vivante > + * GPUs in the system share the same DMA constraints. > + */ > + of_dma_configure(&pdev->dev, np, true); > + > + ret = platform_device_add(pdev); > + if (ret) { > + platform_device_put(pdev); > of_node_put(np); > goto unregister_platform_driver; > } > + > etnaviv_drm = pdev; > of_node_put(np); > break; > -- > 2.19.0 >
Hi Lucas, On Fri, 2018-09-14 at 11:24 +0200, Lucas Stach wrote: > The etnaviv device is a virtual device backing the DRM device, which may > drive multiple hardware GPU core devies. As most of the dma-mapping handling > is done through the virtual device, we need to make sure that a proper DMA > setup is in place. The easiest way to get a reasonable configuration is > to let the virtual device share the DMA configuration with one of the GPU > devices, so call of_dma_configure() with the right parameters manually. > > This assumes that all etnaviv driven GPU devices in the system share the > same DMA configuration. If we ever encounter a SoC where the GPUs are on > busses with different offsets or behind different IOMMUs that will require > much deeper changes to the driver, as we would need to implement etnaviv > specific versions of most of the DRM helper functions. > > For now we should be fine with this solution. This works fine on HSDK, thanks! Tested-By: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> > > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> > --- > drivers/gpu/drm/etnaviv/etnaviv_drv.c | 27 +++++++++++++++++++++------ > 1 file changed, 21 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c > index 9b2720b41571..83c1f46670bf 100644 > --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c > +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c > @@ -592,8 +592,6 @@ static int etnaviv_pdev_probe(struct platform_device *pdev) > struct device *dev = &pdev->dev; > struct component_match *match = NULL; > > - dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32)); > - > if (!dev->platform_data) { > struct device_node *core_node; > > @@ -655,13 +653,30 @@ static int __init etnaviv_init(void) > for_each_compatible_node(np, NULL, "vivante,gc") { > if (!of_device_is_available(np)) > continue; > - pdev = platform_device_register_simple("etnaviv", -1, > - NULL, 0); > - if (IS_ERR(pdev)) { > - ret = PTR_ERR(pdev); > + > + pdev = platform_device_alloc("etnaviv", -1); > + if (!pdev) { > + ret = -ENOMEM; > + of_node_put(np); > + goto unregister_platform_driver; > + } > + pdev->dev.coherent_dma_mask = DMA_BIT_MASK(40); > + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; > + > + /* > + * Apply the same DMA configuration to the virtual etnaviv > + * device as the GPU we found. This assumes that all Vivante > + * GPUs in the system share the same DMA constraints. > + */ > + of_dma_configure(&pdev->dev, np, true); > + > + ret = platform_device_add(pdev); > + if (ret) { > + platform_device_put(pdev); > of_node_put(np); > goto unregister_platform_driver; > } > + > etnaviv_drm = pdev; > of_node_put(np); > break;
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index 9b2720b41571..83c1f46670bf 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c @@ -592,8 +592,6 @@ static int etnaviv_pdev_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct component_match *match = NULL; - dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32)); - if (!dev->platform_data) { struct device_node *core_node; @@ -655,13 +653,30 @@ static int __init etnaviv_init(void) for_each_compatible_node(np, NULL, "vivante,gc") { if (!of_device_is_available(np)) continue; - pdev = platform_device_register_simple("etnaviv", -1, - NULL, 0); - if (IS_ERR(pdev)) { - ret = PTR_ERR(pdev); + + pdev = platform_device_alloc("etnaviv", -1); + if (!pdev) { + ret = -ENOMEM; + of_node_put(np); + goto unregister_platform_driver; + } + pdev->dev.coherent_dma_mask = DMA_BIT_MASK(40); + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; + + /* + * Apply the same DMA configuration to the virtual etnaviv + * device as the GPU we found. This assumes that all Vivante + * GPUs in the system share the same DMA constraints. + */ + of_dma_configure(&pdev->dev, np, true); + + ret = platform_device_add(pdev); + if (ret) { + platform_device_put(pdev); of_node_put(np); goto unregister_platform_driver; } + etnaviv_drm = pdev; of_node_put(np); break;
The etnaviv device is a virtual device backing the DRM device, which may drive multiple hardware GPU core devies. As most of the dma-mapping handling is done through the virtual device, we need to make sure that a proper DMA setup is in place. The easiest way to get a reasonable configuration is to let the virtual device share the DMA configuration with one of the GPU devices, so call of_dma_configure() with the right parameters manually. This assumes that all etnaviv driven GPU devices in the system share the same DMA configuration. If we ever encounter a SoC where the GPUs are on busses with different offsets or behind different IOMMUs that will require much deeper changes to the driver, as we would need to implement etnaviv specific versions of most of the DRM helper functions. For now we should be fine with this solution. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> --- drivers/gpu/drm/etnaviv/etnaviv_drv.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-)