Re: [PATCH v2 8/9] ARM: dts: at91: sam9x60ek: Enable NAND support

[<Eugen.Hristev@microchip.com>]

On 8/31/22 5:19 PM, Michael Nazzareno Trimarchi wrote:
> Hi
> 
> On Wed, Aug 31, 2022 at 3:31 PM <Eugen.Hristev@microchip.com> wrote:
>>
>> On 8/31/22 4:14 PM, Michael Nazzareno Trimarchi wrote:
>>> Hi
>>>
>>> On Mon, Aug 29, 2022 at 8:20 AM Balamanikandan Gunasundar
>>> <balamanikandan.gunasundar@microchip.com> wrote:
>>>>
>>>> Enable the EBI and NAND flash controller. Define the pinctrl and
>>>> partition table
>>>>
>>>> Signed-off-by: Balamanikandan Gunasundar <balamanikandan.gunasundar@microchip.com>
>>>> ---
>>>>    arch/arm/dts/sam9x60ek.dts | 103 +++++++++++++++++++++++++++++++++++++
>>>>    1 file changed, 103 insertions(+)
>>>>
>>>> diff --git a/arch/arm/dts/sam9x60ek.dts b/arch/arm/dts/sam9x60ek.dts
>>>> index 54c694bd78..6cb81dd90f 100644
>>>> --- a/arch/arm/dts/sam9x60ek.dts
>>>> +++ b/arch/arm/dts/sam9x60ek.dts
>>>> @@ -80,6 +80,44 @@
>>>>                           };
>>>>
>>>>                           pinctrl {
>>>> +                                       nand {
>>>
>>> I can see two tabs here. You don't need it. The indentation go far on the right
>>>
>>>> +                                               pinctrl_nand_oe_we: nand-oe-we-0 {
>>>> +                                                       atmel,pins =
>>>> +                                                               <AT91_PIOD 0 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 1 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)>;
>>>> +                                               };
>>>> +
>>>> +                                               pinctrl_nand_rb: nand-rb-0 {
>>>> +                                                       atmel,pins =
>>>> +                                                               <AT91_PIOD 5 AT91_PERIPH_GPIO AT91_PINCTRL_PULL_UP>;
>>>> +                                               };
>>>> +
>>>> +                                               pinctrl_nand_cs: nand-cs-0 {
>>>> +                                                       atmel,pins =
>>>> +                                                               <AT91_PIOD 4 AT91_PERIPH_GPIO AT91_PINCTRL_PULL_UP>;
>>>> +                                               };
>>>> +                                       };
>>>> +
>>>> +                                       ebi {
>>>> +                                               pinctrl_ebi_data_0_7: ebi-data-lsb-0 {
>>>> +                                                       atmel,pins =
>>>> +                                                               <AT91_PIOD 6 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 7 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 8 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 9 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 10 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 11 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 12 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 13 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)>;
>>>> +                                               };
>>>> +
>>>> +                                               pinctrl_ebi_addr_nand: ebi-addr-0 {
>>>> +                                                       atmel,pins =
>>>> +                                                               <AT91_PIOD 2 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)
>>>> +                                                                AT91_PIOD 3 AT91_PERIPH_A (AT91_PINCTRL_NONE | AT91_PINCTRL_SLEWRATE_DIS)>;
>>>> +                                               };
>>>> +                                       };
>>>> +
>>>
>>> Please remove the ebi and nand block so you have one tab less. Then I
>>> suggest to align to linux dts and refer to pinctrl instead to create
>>> another level of indentation
>>
>> Hello Michael,
>>
>> In Linux I see the nand and ebi block. We have to keep the same DT as in
>> Linux. Do you agree ?
>>
>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/at91-sam9x60ek.dts#n378
>>
> 
> I have seen it already but I don't think that dtsi is aligned with it.
> So you don't have pinctrl: pinctrl@0ffff400 and you can refer
> to this node as it is. Here the question is if we need to continue to
> have a no-align dts component inside the pinctrl and add more
> elements in it. If you look at that file pinctrl_qspi: qspi { is not
> in any block and for the linux should be even before. It should
> be coherent in what we have or in what linux have now. This does not
> block driver review so I think that can be acked by microchip
> maintainers in this part.
> 

Hi Michael,

I have difficulties to follow your reasoning. Could you detail it a bit 
so I can understand what is the problem you are referring to ?

As I see it, the DT in the patch is aligned with Linux. The nodes are 
identical.

Eugen

> Michael
> 
> 
>> Eugen
>>
>>>
>>>>                                           pinctrl_qspi: qspi {
>>>>                                                   atmel,pins =
>>>>                                                           <AT91_PIOB 19 AT91_PERIPH_A AT91_PINCTRL_NONE
>>> This part can be tab back
>>>
>>> Michael
>>>
>>>> @@ -106,6 +144,71 @@
>>>>           };
>>>>    };
>>>>
>>>> +&ebi {
>>>> +       pinctrl-names = "default";
>>>> +       pinctrl-0 = <&pinctrl_ebi_addr_nand &pinctrl_ebi_data_0_7>;
>>>> +       status = "okay";
>>>> +
>>>> +       nand_controller: nand-controller {
>>>> +               pinctrl-names = "default";
>>>> +               pinctrl-0 = <&pinctrl_nand_oe_we &pinctrl_nand_cs &pinctrl_nand_rb>;
>>>> +               status = "okay";
>>>> +
>>>> +               nand@3 {
>>>> +                       reg = <0x3 0x0 0x800000>;
>>>> +                       rb-gpios = <&pioD 5 GPIO_ACTIVE_HIGH>;
>>>> +                       cs-gpios = <&pioD 4 GPIO_ACTIVE_HIGH>;
>>>> +                       nand-bus-width = <8>;
>>>> +                       nand-ecc-mode = "hw";
>>>> +                       nand-ecc-strength = <8>;
>>>> +                       nand-ecc-step-size = <512>;
>>>> +                       nand-on-flash-bbt;
>>>> +                       label = "atmel_nand";
>>>> +
>>>> +                       partitions {
>>>> +                               compatible = "fixed-partitions";
>>>> +                               #address-cells = <1>;
>>>> +                               #size-cells = <1>;
>>>> +
>>>> +                               at91bootstrap@0 {
>>>> +                                       label = "at91bootstrap";
>>>> +                                       reg = <0x0 0x40000>;
>>>> +                               };
>>>> +
>>>> +                               uboot@40000 {
>>>> +                                       label = "u-boot";
>>>> +                                       reg = <0x40000 0xc0000>;
>>>> +                               };
>>>> +
>>>> +                               ubootenvred@100000 {
>>>> +                                       label = "U-Boot Env Redundant";
>>>> +                                       reg = <0x100000 0x40000>;
>>>> +                               };
>>>> +
>>>> +                               ubootenv@140000 {
>>>> +                                       label = "U-Boot Env";
>>>> +                                       reg = <0x140000 0x40000>;
>>>> +                               };
>>>> +
>>>> +                               dtb@180000 {
>>>> +                                       label = "device tree";
>>>> +                                       reg = <0x180000 0x80000>;
>>>> +                               };
>>>> +
>>>> +                               kernel@200000 {
>>>> +                                       label = "kernel";
>>>> +                                       reg = <0x200000 0x600000>;
>>>> +                               };
>>>> +
>>>> +                               rootfs@800000 {
>>>> +                                       label = "rootfs";
>>>> +                                       reg = <0x800000 0x1f800000>;
>>>> +                               };
>>>> +                       };
>>>> +               };
>>>> +       };
>>>> +};
>>>> +
>>>>    &macb0 {
>>>>           phy-mode = "rmii";
>>>>           status = "okay";
>>>> --
>>>> 2.34.1
>>>>
>>>
>>>
>>> --
>>> Michael Nazzareno Trimarchi
>>> Co-Founder & Chief Executive Officer
>>> M. +39 347 913 2170
>>> michael@amarulasolutions.com
>>> __________________________________
>>>
>>> Amarula Solutions BV
>>> Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
>>> T. +31 (0)85 111 9172
>>> info@amarulasolutions.com
>>> www.amarulasolutions.com
>>>
>>
> 
> 
> --
> Michael Nazzareno Trimarchi
> Co-Founder & Chief Executive Officer
> M. +39 347 913 2170
> michael@amarulasolutions.com
> __________________________________
> 
> Amarula Solutions BV
> Joop Geesinkweg 125, 1114 AB, Amsterdam, NL
> T. +31 (0)85 111 9172
> info@amarulasolutions.com
> www.amarulasolutions.com
>