On 12/22/2016 11:02 AM, Heinrich Schuchardt wrote:
> On 12/14/2016 10:52 AM, Neil Armstrong wrote:
>
>> Hi Heinrich,
>>
>> Thanks for testing and for the report,
>> we are still struggling into finding what are these zones and how to label
>> them correctly.
>>
>> We need to identify the zones on all boards, the patch I provided works on a
>> non-odroid-c2 and gxm and gxl boards.
>>
>> Neil
>>
> Hello Neil,
>
> the configuration below works for me on the Hardkernel Odroid C2.
>
> ramoops is needed for CONFIG_PSTORE_RAM.
> Debian Stretch has CONFIG_PSTORE_RAM=m. Same is true for Fedora.
> I have chosen the address arbitrarily. To accommodate 512 MB boards we
> would have to put it below 0x20000000.
> The size parameters are the same as in hisilicon/hi6220-hikey.dts and
> qcom-apq8064-asus-nexus7-flo.dts.
>
> linux,cma is used for contiguous memory assignment. I have taken the
> align parameter from arm-src-kernel-2016-08-18-26e194264c.tar.gz
> provided by Amlogic at
> http://openlinux.amlogic.com:8000/download/ARM/kernel/ .
> See Documentation/DMA-API.txt for the usage of align.
> They use the same value 0x400000 for all GXBB boards.
> So we want to put this zone into meson-gxbb.dtsi.
>
> secmon is used by drivers/firmware/meson/meson_sm.c.
> Amlogic uses the same address range for all 64bit boards.
>
> memory@0 {
> device_type = "memory";
> linux,usable-memory = <0x0 0x1000000 0x0 0x7f000000>;
> };
>
> reserved-memory {
> #address-cells = <0x2>;
> #size-cells = <0x2>;
> ranges;
>
> ramoops@0x23f00000 {
> compatible = "ramoops";
> reg = <0x0 0x23f00000 0x0 0x100000>;
> record-size = <0x20000>;
> console-size = <0x20000>;
> ftrace-size = <0x20000>;
> };
>
> secmon: secmon {
> compatible = "amlogic, aml_secmon_memory";
> reg = <0x0 0x10000000 0x0 0x200000>;
> no-map;
> };
>
> linux,cma {
> compatible = "shared-dma-pool";
> reusable;
> size = <0x0 0xbc00000>;
> alignment = <0x0 0x400000>;
> linux,cma-default;
> };
> };
>
> Best regards
>
> Heinrich Schuchardt
>
Hello Neil,
it really makes a difference if we write
memory@0 {
device_type = "memory";
linux,usable-memory = <0x0 0x1000000 0x0 0x7f000000>;
};
or
memory@0 {
device_type = "memory";
reg = <0x0 0x1000000 0x0 0x7f000000>;
};
The second version leads to failure of the Odroid C2.
When I looked at /sys/firmware/fdt I saw this difference:
--- fails
+++ works
memory@0 {
- device_type = "memory";
reg = <0x0 0x0 0x0 0x78000000>;
+ device_type = "memory";
+ linux,usable-memory = <0x0 0x1000000 0x0 0x7f000000>;
};
I found the following sentence in the NXP forum:
In case you want to overwrite the memory usage passed from u-boot, you
can use "linux,usable-memory".
https://community.nxp.com/thread/382284
Best regards
Heinrich Schuchardt
