Hi Jan,
> On Jun 21, 2016, at 14:43 , Jan Kiszka <jan.kis...@siemens.com> wrote:
>
> On 2016-06-21 13:35, Pantelis Antoniou wrote:
>> Hi Jan,
>>
>>> On Jun 21, 2016, at 14:22 , Jan Kiszka <jan.kis...@siemens.com> wrote:
>>>
>>> On 2016-06-21 12:24, Pantelis Antoniou wrote:
>>>> Hi Jan,
>>>>
>>>>> On Jun 21, 2016, at 13:13 , Jan Kiszka <jan.kis...@siemens.com> wrote:
>>>>>
>>>>> Hi Pantelis,
>>>>>
>>>>> coming back to this topic:
>>>>>
>>>>> On 2016-06-09 08:03, Jan Kiszka wrote:
>>>>>> OK, trial and error, and some interesting insights: I've played with DT
>>>>>> fragments and the overlay configfs patch of Pantelis [1] to have a
>>>>>> convenient start. Interestingly, I wasn't able to load a fragment that
>>>>>> followed the format specification for overlays ("Failed to resolve
>>>>>> tree"). By chance, I got this one working:
>>>>>>
>>>>>> /dts-v1/;
>>>>>> / {
>>>>>> fragment {
>>>>>> target-path = "/soc@01c00000";
>>>>>> __overlay__ {
>>>>>> #address-cells = <2>;
>>>>>> #size-cells = <2>;
>>>>>>
>>>>>> vpci@0x2000000 {
>>>>>> compatible = "pci-host-cam-generic";
>>>>>> device_type = "pci";
>>>>>> #address-cells = <3>;
>>>>>> #size-cells = <2>;
>>>>>> reg = <0 0x2000000 0 0x1000000>;
>>>>>> ranges =
>>>>>> <0x02000000 0x00 0x10000000 0x00
>>>>>> 0x10000000 0x00 0x30000000>;
>>>>>> };
>>>>>> };
>>>>>> };
>>>>>> };
>>>>>>
>>>>>> It successfully makes a BananaPi kernel add a pci host with the
>>>>>> specified config space and MMIO window.
>>>>>>
>>>>>> [ 81.619583] PCI host bridge /soc@01c00000/vpci@0x2000000 ranges:
>>>>>> [ 81.619610] No bus range found for /soc@01c00000/vpci@0x2000000,
>>>>>> using [bus 00-ff]
>>>>>> [ 81.619634] MEM 0x10000000..0x3fffffff -> 0x10000000
>>>>>> [ 81.620482] pci-host-generic 2000000.vpci: ECAM at [mem
>>>>>> 0x02000000-0x02ffffff] for [bus 00-ff]
>>>>>> [ 81.620779] pci-host-generic 2000000.vpci: PCI host bridge to bus
>>>>>> 0000:00
>>>>>> [ 81.620801] pci_bus 0000:00: root bus resource [bus 00-ff]
>>>>>> [ 81.620814] pci_bus 0000:00: root bus resource [mem
>>>>>> 0x10000000-0x3fffffff]
>>>>>> [ 81.620851] PCI: bus0: Fast back to back transfers enabled
>>>>>>
>>>>>> So, no /plugin/ statement, no phandles resolution. This format even
>>>>>> builds with the in-kernel dtc. Any explanations? Does the code make
>>>>>> sense (at least it builds without warnings)?
>>>>>>
>>>>>> Now I need to back this with some code in Jailhouse.
>>>>>
>>>>> Meanwhile I got a virtual PCI device recognized by Linux when running
>>>>> over Jailhouse. However, my hack above doesn't get me to proper
>>>>> interrupt mapping yet. This is what I was trying with upstream dtc:
>>>>>
>>>>> /dts-v1/;
>>>>> / {
>>>>> compatible = "lemaker,bananapi", "allwinner,sun7i-a20";
>>>>>
>>>>> fragment@0 {
>>>>> target-path = "/soc@01c00000";
>>>>> __overlay__ {
>>>>> #address-cells = <2>;
>>>>> #size-cells = <2>;
>>>>>
>>>>> vpci@2000000 {
>>>>> compatible = "pci-host-ecam-generic";
>>>>> device_type = "pci";
>>>>> bus-range = <0 0>;
>>>>> #address-cells = <3>;
>>>>> #size-cells = <2>;
>>>>> #interrupt-cells = <1>;
>>>>> interrupt-map-mask = <0 0 0 7>;
>>>>> interrupt-map = <0 0 0 1 &gic 0 0 0 123 4>,
>>>>> <0 0 0 2 &gic 0 0 0 124 4>,
>>>>> <0 0 0 3 &gic 0 0 0 125 4>,
>>>>> <0 0 0 4 &gic 0 0 0 126 4>;
>>>>> reg = <0 0x2000000 0 0x100000>;
>>>>> ranges =
>>>>> <0x02000000 0x00 0x10000000 0x00
>>>>> 0x10000000 0x00 0x30000000>;
>>>>> };
>>>>> };
>>>>> };
>>>>>
>>>>> gic: fragment@1 {
>>>>> target-path = "/soc@01c00000/interrupt-controller@01c81000";
>>>>> __overlay__ {
>>>>> };
>>>>> };
>>>>> };
>>>>>
>>>>
>>>> ^ This is not going to work: You need the reference to the real gic not
>>>> the empty fragment
>>>> here that has a target there.
>>>>
>>>> You need to compile with the correct dtc, and you also need to compile the
>>>> base dts
>>>> with dtc too, using the -@ flag. You can hack around it by adding
>>>> something like
>>>>
>>>> __symbols__ {
>>>> gic = "/soc@01c00000/interrupt-controller@01c81000”;
>>>> };
>>>>
>>>> But you really need the __symbols__ node of the base dts generated by the
>>>> dtc proper cause
>>>> the above is a dirty hack.
>>>>
>>>
>>> OK, re-building the kernel with DTC="/your/dtc -@", thus building the
>>> base dtb with symbols, fixes proper overlay format loading.
>>>
>>> However, no luck yet with the interrupt topic - maybe a different issue.
>>> Digging deeper…
>>>
>> Remove the gic: fragment and build both the kernel and the overlay with the
>> -@ option.
>> That’s what makes it not to work.
>
> That's what I did, of course.
>
> I've now
>
> /dts-v1/;
> // magic: 0xd00dfeed
> // totalsize: 0x448 (1096)
> // off_dt_struct: 0x38
> // off_dt_strings: 0x3c0
> // off_mem_rsvmap: 0x28
> // version: 17
> // last_comp_version: 16
> // boot_cpuid_phys: 0x0
> // size_dt_strings: 0x88
> // size_dt_struct: 0x388
>
> / {
> compatible = "lemaker,bananapi", "allwinner,sun7i-a20";
> fragment@0 {
> target = <0xffffffff>;
> __overlay__ {
> #address-cells = <0x00000002>;
> #size-cells = <0x00000002>;
> vpci@2000000 {
> compatible = "pci-host-ecam-generic";
> device_type = "pci";
> bus-range = <0x00000000 0x00000000>;
> #address-cells = <0x00000003>;
> #size-cells = <0x00000002>;
> #interrupt-cells = <0x00000001>;
> interrupt-map-mask = <0x00000000 0x00000000 0x00000000
> 0x00000007>;
> interrupt-map = <0x00000000 0x00000000 0x00000000 0x00000001
> 0xffffffff 0x00000000 0x00000000 0x00000000 0x0000007b 0x00000004 0x00000000
> 0x00000000 0x00000000 0x00000002 0xffffffff 0x00000000 0x00000000 0x00000000
> 0x0000007c 0x00000004 0x00000000 0x00000000 0x00000000 0x00000003 0xffffffff
> 0x00000000 0x00000000 0x00000000 0x0000007d 0x00000004 0x00000000 0x00000000
> 0x00000000 0x00000004 0xffffffff 0x00000000 0x00000000 0x00000000 0x0000007e
> 0x00000004>;
> reg = <0x00000000 0x02000000 0x00000000 0x00100000>;
> ranges = <0x02000000 0x00000000 0x10000000 0x00000000
> 0x10000000 0x00000000 0x30000000>;
> };
> };
> };
> __symbols__ {
> };
> __fixups__ {
> soc = "/fragment@0:target:0";
> gic = "/fragment@0/__overlay__/vpci@2000000:interrupt-map:16",
> "/fragment@0/__overlay__/vpci@2000000:interrupt-map:56",
> "/fragment@0/__overlay__/vpci@2000000:interrupt-map:96",
> "/fragment@0/__overlay__/vpci@2000000:interrupt-map:136";
> };
> __local_fixups__ {
> };
> };
>
> and a base dtb with a symbols section and all the required ones
> included.
>
OK, this should make things work. Did you try sticking this in the base dts and
see if it works there?
> Jan
>
> --
> Siemens AG, Corporate Technology, CT RDA ITP SES-DE
> Corporate Competence Center Embedded Linux
