Re: [EXT] [PATCH 2/2] arm64: dts: ls1028a: add "fsl,vf610-edma" compatible

[Michael Walle <michael@walle.cc>]

Hi Peng,

Am 2020-03-07 11:32, schrieb Peng Ma:
>> -----Original Message-----
>> From: Michael Walle <michael@walle.cc>
>> Sent: 2020年3月7日 17:26
>> To: Peng Ma <peng.ma@nxp.com>
>> Cc: dmaengine@vger.kernel.org; devicetree@vger.kernel.org;
>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org; 
>> Vinod Koul
>> <vkoul@kernel.org>; Rob Herring <robh+dt@kernel.org>; Mark Rutland
>> <mark.rutland@arm.com>; Shawn Guo <shawnguo@kernel.org>; Leo Li
>> <leoyang.li@nxp.com>
>> Subject: Re: [EXT] [PATCH 2/2] arm64: dts: ls1028a: add 
>> "fsl,vf610-edma"
>> compatible
>> 
>> Caution: EXT Email
>> 
>> Hi Peng,
>> 
>> Am 2020-03-07 03:09, schrieb Peng Ma:
>>>> -----Original Message-----
>>>> From: Michael Walle <michael@walle.cc>
>>>> Sent: 2020年3月7日 4:54
>>>> To: dmaengine@vger.kernel.org; devicetree@vger.kernel.org;
>>>> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
>>>> Cc: Vinod Koul <vkoul@kernel.org>; Rob Herring <robh+dt@kernel.org>;
>>>> Mark Rutland <mark.rutland@arm.com>; Shawn Guo
>> <shawnguo@kernel.org>;
>>>> Leo Li <leoyang.li@nxp.com>; Peng Ma <peng.ma@nxp.com>; Michael 
>>>> Walle
>>>> <michael@walle.cc>
>>>> Subject: [EXT] [PATCH 2/2] arm64: dts: ls1028a: add "fsl,vf610-edma"
>>>> compatible
>>>> 
>>>> Caution: EXT Email
>>>> 
>>>> The bootloader does the IOMMU fixup and dynamically adds the 
>>>> "iommus"
>>>> property to devices according to its compatible string. In case of
>>>> the eDMA controller this property is missing. Add it. After that the
>>>> IOMMU will work with the eDMA core.
>>>> 
>>>> Signed-off-by: Michael Walle <michael@walle.cc>
>>>> ---
>>>> arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>> 
>>>> diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
>>>> b/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
>>>> index b152fa90cf5c..aa467bff2209 100644
>>>> --- a/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
>>>> +++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
>>>> @@ -447,7 +447,7 @@
>>>> 
>>>>                edma0: dma-controller@22c0000 {
>>>>                        #dma-cells = <2>;
>>>> -                       compatible = "fsl,ls1028a-edma";
>>>> +                       compatible = "fsl,ls1028a-edma",
>>>> + "fsl,vf610-edma";
>>> Hi Michael,
>>> 
>>> You should change it on bootloader instead of kernel, Some Reg of
>>> LS1028a is different from others, So we used compatible
>>> "fsl,ls1028a-edm" to distinguish "
>>> fsl,vf610-edma".
>> 
>> Yes this might be the right thing to do. So since it is NXPs 
>> bootloader feel free to
>> fix that ;) Looking at the u-boot code right now, I don't even know it 
>> that is the
>> right fix at all. The fixup code in u-boot is SoC independent (its in 
>> fsl_icid.h and is
>> enabled with CONFIG_LSCH3, ie your chassis version). For example, the 
>> sdhc
>> fixup will scan the nodes for "compatible = fsl,esdhc", which is also 
>> the
>> secondary compatible for the "ls1028a-esdhc" compatible.
>> 
>> And here is another reason to have it this way: we need backwards 
>> compatibility,
>> the are already boards out there whose bootloader will fix-up the 
>> "old" node.
>> Thus I don't see any other possibilty.
>> 
> [Peng Ma] OK, There is non fixed on uboot.
> I will fix it on uboot, if you want to use now, please change the
> uboot as below:

As I told you, I cannot be changed for shipped bootloaders. While it can 
be
changed for newer ones, I would really like to retain backwards 
compatibility.
And so should you.

That being said, I don't see a problem in having both compatibles. Linux
will use the ls1028a-emda one and u-boot will fix up the "older"
vf610-edma one.

Unfortunately, this patch will not only affect eDMA but all other 
drivers
which uses eDMA, eg. sound, lpuart, i2c and maybe DSPI.

-michael

> 
> diff --git a/arch/arm/cpu/armv8/fsl-layerscape/ls1028_ids.c
> b/arch/arm/cpu/armv8/fsl-layerscape/ls1028_ids.c
> index d9d125e8ba..db9dd69548 100644
> --- a/arch/arm/cpu/armv8/fsl-layerscape/ls1028_ids.c
> +++ b/arch/arm/cpu/armv8/fsl-layerscape/ls1028_ids.c
> @@ -14,7 +14,7 @@ struct icid_id_table icid_tbl[] = {
>         SET_SDHC_ICID(1, FSL_SDMMC_STREAM_ID),
>         SET_SDHC_ICID(2, FSL_SDMMC2_STREAM_ID),
>         SET_SATA_ICID(1, "fsl,ls1028a-ahci", FSL_SATA1_STREAM_ID),
> -       SET_EDMA_ICID(FSL_EDMA_STREAM_ID),
> +       SET_EDMA_ICID_LS1028(FSL_EDMA_STREAM_ID),
>         SET_QDMA_ICID("fsl,ls1028a-qdma", FSL_DMA_STREAM_ID),
>         SET_GPU_ICID("fsl,ls1028a-gpu", FSL_GPU_STREAM_ID),
>         SET_DISPLAY_ICID(FSL_DISPLAY_STREAM_ID),
> diff --git a/arch/arm/include/asm/arch-fsl-layerscape/fsl_icid.h
> b/arch/arm/include/asm/arch-fsl-layerscape/fsl_icid.h
> index 37e2fe4e66..15d0b60dbe 100644
> --- a/arch/arm/include/asm/arch-fsl-layerscape/fsl_icid.h
> +++ b/arch/arm/include/asm/arch-fsl-layerscape/fsl_icid.h
> @@ -144,6 +144,10 @@ extern int fman_icid_tbl_sz;
>         SET_GUR_ICID("fsl,vf610-edma", streamid, spare3_amqr,\
>                 EDMA_BASE_ADDR)
> 
> +#define SET_EDMA_ICID_LS1028(streamid) \
> +       SET_GUR_ICID("fsl,ls1028a-edma", streamid, spare3_amqr,\
> +               EDMA_BASE_ADDR)
> +
>  #define SET_GPU_ICID(compat, streamid) \
>         SET_GUR_ICID(compat, streamid, misc1_amqr,\
>                 GPU_BASE_ADDR)
> 
> BR,
> Peng
>> -michael
>> 
>>> 
>>> Thanks,
>>> Peng
>>>>                        reg = <0x0 0x22c0000 0x0 0x10000>,
>>>>                              <0x0 0x22d0000 0x0 0x10000>,
>>>>                              <0x0 0x22e0000 0x0 0x10000>;
>>>> --
>>>> 2.20.1