Re: [PATCH v12 1/3] drm: rockchip: Add basic drm driver

From: Mark yao
Date: Tue Nov 18 2014 - 20:10:14 EST

On 2014å11æ18æ 22:24, Daniel Vetter wrote:
On Tue, Nov 18, 2014 at 02:21:30PM +0100, Boris Brezillon wrote:
Hi Daniel,

On Tue, 18 Nov 2014 09:32:34 +0100
Daniel Vetter <daniel@xxxxxxxx> wrote:

On Tue, Nov 18, 2014 at 04:00:29PM +0800, Mark Yao wrote:
From: Mark yao <mark.yao@xxxxxxxxxxxxxx>

This patch adds the basic structure of a DRM Driver for Rockchip Socs.

Signed-off-by: Mark Yao <mark.yao@xxxxxxxxxxxxxx>
Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
Acked-by: Daniel Vetter <daniel@xxxxxxxx>
Reviewed-by: Rob Clark <robdclark@xxxxxxxxx>
Changes in v2:
- use the component framework to defer main drm driver probe
until all VOP devices have been probed.
- use dma-mapping API with ARM_DMA_USE_IOMMU, create dma mapping by
master device and each vop device can shared the drm dma mapping.
- use drm_crtc_init_with_planes and drm_universal_plane_init.
- remove unnecessary middle layers.
- add cursor set, move funcs to rockchip drm crtc.
- use vop reset at first init
- reference framebuffer when used and unreference when swap out vop

Changes in v3:
- change "crtc->fb" to "crtc->primary-fb"
Adviced by Daniel Vetter
- init cursor plane with universal api, remove unnecessary cursor set,move

Changes in v4:
Adviced by David Herrmann
- remove drm_platform_*() usage, use register drm device directly.
Minor fixup for that part below.


+static int rockchip_drm_bind(struct device *dev)
+ struct drm_device *drm;
+ int ret;
+ drm = drm_dev_alloc(&rockchip_drm_driver, dev);
+ if (!drm)
+ return -ENOMEM;
+ ret = drm_dev_set_unique(drm, "%s", dev_name(dev));
+ if (ret)
+ goto err_free;
Please call rockchip_drm_load here directly and don't put it as the ->load
function into the driver vtable. The point of the alloc/register split is
that the driver can be completely set up _before_ we register anything.
But for backwards compat and historical reasons ->load is called somewhere
in the middle (so that you could access the minor nodes if needed, since
some drivers do that).
I tried to do the same in the atmel-hlcdc DRM driver, but I need the
primary drm_minor to register the connectors (see this kernel
backtrace [1]), which means I either initialize the connector in the
wrong place (currently part of the drm load process), or I just can't
call atmel_hlcdc_dc_load before registering the drm device...
Hm right, wonder who that works with rockchip tbh.

We did split up the drm_connector setup into _init and register, so if you
want to do this then you need to move the call to drm_connector_register
below the call to drm_dev_register.

We should probably have a drm_connectors_register_all helper which does
this for all connectors on the connector list. And also grabs the
appropriate lock.

I guess it's somewhat obvious that no one yet actually tried this ;-)
right, I re-test the driver with it, get the same problem with Boris.
I should move drm_connector_register below the drm_dev_register.

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