[U-Boot] About convert to LIVE DT

[Kever Yang]

Simon,


On 02/12/2018 10:35 PM, Simon Glass wrote:
> Hi Kever,
>
> On 4 February 2018 at 18:00, Kever Yang <kever.yang at rock-chips.com> wrote:
>>
>> On 02/04/2018 09:40 PM, Simon Glass wrote:
>>> Hi Kever,
>>>
>>> On 4 February 2018 at 00:44, Kever Yang <kever.yang at rock-chips.com> wrote:
>>>> Hi Simon, Philipp,
>>>>
>>>>     When I try to convert to live dt, I fount there are many APIs work
>>>> in fdt are missing in live dt,
>>>>
>>>> do you have any suggestion to add these APIs in live dt quickly? I need:
>>>>
>>>> fdtdec_get_addr_size_auto_noparent
>>> dev_read_addr_size() - not having a parent doesn't happen with livetree
>>>
>>>> fdt_alloc_phandle
>>> We don't support changing the live tree yet.
>>>
>>>> fdt_device_is_available
>>> dev_read_enabled()
>>>
>>>> fdt_for_each_subnode
>>> dev_for_each_subnode()
>>>
>>>> fdt_getprop
>>> dev_read_prop()
>>>
>>>> fdt_getprop_u32_default_node
>>> This is an odd function. Can you first check that the property exists,
>>> and then use a dev_read_...() function to read it?
>>>
>>>> fdt_get_named_resource
>>> dev_read_resource_byname()
>>>
>>>> fdt_get_name
>>> dev_read_name() - although I see that the comment is wrong
>>>
>>>> fdt_get_path
>>> Not available but you can add it
>>>
>>>> fdt_get_phandle
>>> Why do you need this?
>> Most of the APIs are used in this file or other files in this folder,
>> https://github.com/rockchip-linux/u-boot/blob/release/drivers/video/drm/rockchip_display.c
>> It needs to handle quite complicated dts node for display system in
>> rockchip drm display driver(not upstream yet):
>> https://github.com/rockchip-linux/u-boot/blob/release/arch/arm/dts/rk3128.dtsi#L421
>> https://github.com/rockchip-linux/u-boot/blob/release/arch/arm/dts/rk3126-bnd-d708.dts#L114
> One difference I see with Linux is that U-Boot creates devices for all
> nodes automatically, provided that they have a compatible string and
> matching driver. This should simplify things in U-Boot.
>
> The supernode-at-depth function looks like it just takes the parent of
> the parent when an argument of -2 is used.
>
> The existing rockchip driver in U-Boot handles a similar binding,
> doesn't it? It has phandles and multiple nodes and subnodes.

Yes, but it does not able to migrate to support both live dt and fdt,
because there is no same api in live dt, and here is what I do locally
for live dt:
 823                 phandle = ofnode_read_u32_default(node, "connect",
-1);        
 824                 if (phandle < 0)
{                                             
 825                         printf("Warn: can't find connect node's
handle\n");    
 826                        
continue;                                              
 827                
}                                                              
 828                 ep_node =
of_find_node_by_phandle(phandle);                    
 829                 if (!ofnode_valid(np_to_ofnode(ep_node)))
{                    
 830                         printf("Warn: can't find endpoint node from
phandle\n");
 831                        
continue;                                              
 832                
}                                                              
 833                 port_node =
of_get_parent(ep_node);                            
 834                 if (!ofnode_valid(np_to_ofnode(port_node)))
{                  
 835                         printf("Warn: can't find port node from
phandle\n");   
 836                        
continue;                                              
 837                
}                                                              
 838                 vop_node =
of_get_parent(port_node);                           
 839                 if (!ofnode_valid(np_to_ofnode(vop_node)))
{                   
 840                         printf("Warn: can't find crtc node from
phandle\n");   
 841                        
continue;                                              
 842                
}                                                              
 843                 ret =
uclass_get_device_by_ofnode(UCLASS_VIDEO_CRTC,           
 844                                                  
np_to_ofnode(vop_node),      
 845                                                   &crtc_dev);

In usb phy, we have similar requirement, but only need find "-1" depth
parent.

Thanks,
- Kever
>
>> Thanks,
>> - Kever
>>>> fdt_node_depth
>>>> fdt_node_offset_by_phandle
>>>> fdt_node_offset_by_phandle_node
>>> uclass_get_device_by_phandle() or similar?
>>>
>>>> fdt_path_offset
>>> ofnode_path() although it does not return a device. Best avoided.
>>>
>>>> fdt_set_phandle
>>> You can't change the livtree at present.
>>>
>>>> fdt_stringlist_get
>>> dev_read_string_index()
>>>
>>>> fdt_stringlist_search
>>> dev_read_stringlist_search()
>>>
>>>> fdt_subnode_offset
>>> Why do you want that?
>>>
>>>> fdt_supernode_atdepth_offset
>>> This should be found by scanning, generally using separate drivers for
>>> each DT node.
>>>
>>> If you like you could send a patch with the info above, to
>>> doc/driver-model/livetree.txt to help others.
> Regards,
> Simon
>