[PATCH v6 02/17] riscv: sifive: fu540: Use OTP DM driver for serial environment variable

[Pragnesh Patel]

Hi Jagan,

>-----Original Message-----
>From: Jagan Teki <jagan at amarulasolutions.com>
>Sent: 02 April 2020 14:59
>To: Pragnesh Patel <pragnesh.patel at sifive.com>
>Cc: U-Boot-Denx <u-boot at lists.denx.de>; Atish Patra
><atish.patra at wdc.com>; palmerdabbelt at google.com; Bin Meng
><bmeng.cn at gmail.com>; Paul Walmsley <paul.walmsley at sifive.com>; Troy
>Benjegerdes <troy.benjegerdes at sifive.com>; Anup Patel
><anup.patel at wdc.com>; Sagar Kadam <sagar.kadam at sifive.com>; Rick Chen
><rick at andestech.com>; Palmer Dabbelt <palmer at dabbelt.com>
>Subject: Re: [PATCH v6 02/17] riscv: sifive: fu540: Use OTP DM driver for serial
>environment variable
>
>[External Email] Do not click links or attachments unless you recognize the
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>On Thu, Apr 2, 2020 at 2:54 PM Pragnesh Patel <pragnesh.patel at sifive.com>
>wrote:
>>
>>
>> Hi Jagan,
>>
>> >-----Original Message-----
>> >From: Jagan Teki <jagan at amarulasolutions.com>
>> >Sent: 02 April 2020 14:49
>> >To: Pragnesh Patel <pragnesh.patel at sifive.com>
>> >Cc: U-Boot-Denx <u-boot at lists.denx.de>; Atish Patra
>> ><atish.patra at wdc.com>; palmerdabbelt at google.com; Bin Meng
>> ><bmeng.cn at gmail.com>; Paul Walmsley <paul.walmsley at sifive.com>;
>Troy
>> >Benjegerdes <troy.benjegerdes at sifive.com>; Anup Patel
>> ><anup.patel at wdc.com>; Sagar Kadam <sagar.kadam at sifive.com>; Rick
>Chen
>> ><rick at andestech.com>; Palmer Dabbelt <palmer at dabbelt.com>
>> >Subject: Re: [PATCH v6 02/17] riscv: sifive: fu540: Use OTP DM driver
>> >for serial environment variable
>> >
>> >[External Email] Do not click links or attachments unless you
>> >recognize the sender and know the content is safe
>> >
>> >On Sun, Mar 29, 2020 at 10:36 PM Pragnesh Patel
>> ><pragnesh.patel at sifive.com> wrote:
>> >>
>> >> Use the OTP DM driver to set the serial environment variable.
>> >>
>> >> Signed-off-by: Pragnesh Patel <pragnesh.patel at sifive.com>
>> >> ---
>> >>  arch/riscv/dts/fu540-c000-u-boot.dtsi         |  14 +++
>> >>  .../dts/hifive-unleashed-a00-u-boot.dtsi      |   6 +
>> >>  board/sifive/fu540/Kconfig                    |   2 +
>> >>  board/sifive/fu540/fu540.c                    | 111 ++++++------------
>> >>  4 files changed, 61 insertions(+), 72 deletions(-)  create mode
>> >> 100644 arch/riscv/dts/fu540-c000-u-boot.dtsi
>> >>  create mode 100644 arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi
>> >>
>> >> diff --git a/arch/riscv/dts/fu540-c000-u-boot.dtsi
>> >> b/arch/riscv/dts/fu540-c000-u-boot.dtsi
>> >> new file mode 100644
>> >> index 0000000000..db55773bd2
>> >> --- /dev/null
>> >> +++ b/arch/riscv/dts/fu540-c000-u-boot.dtsi
>> >> @@ -0,0 +1,14 @@
>> >> +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
>> >> +/*
>> >> + * (C) Copyright 2019 SiFive, Inc
>> >> + */
>> >> +
>> >> +/ {
>> >> +       soc {
>> >> +               otp: otp at 10070000 {
>> >> +                       compatible = "sifive,fu540-c000-otp";
>> >> +                       reg = <0x0 0x10070000 0x0 0x0FFF>;
>> >> +                       fuse-count = <0x1000>;
>> >> +               };
>> >> +       };
>> >> +};
>> >> diff --git a/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi
>> >> b/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi
>> >> new file mode 100644
>> >> index 0000000000..f1735c1385
>> >> --- /dev/null
>> >> +++ b/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi
>> >> @@ -0,0 +1,6 @@
>> >> +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
>> >> +/*
>> >> + * Copyright (C) 2019 SiFive, Inc
>> >> + */
>> >> +
>> >> +#include "fu540-c000-u-boot.dtsi"
>> >> diff --git a/board/sifive/fu540/Kconfig
>> >> b/board/sifive/fu540/Kconfig index 5ca21474de..900197bbb2 100644
>> >> --- a/board/sifive/fu540/Kconfig
>> >> +++ b/board/sifive/fu540/Kconfig
>> >> @@ -48,5 +48,7 @@ config BOARD_SPECIFIC_OPTIONS # dummy
>> >>         imply SIFIVE_GPIO
>> >>         imply CMD_GPIO
>> >>         imply SMP
>> >> +       imply MISC
>> >> +       imply SIFIVE_OTP
>> >
>> >Mark this default y if it is SIFIVE.
>>
>> All other SiFive drivers (SPI_SIFIVE, SIFIVE_GPIO) are enabled by "imply", so I
>am following the same. I think "imply" will make it default y.
>
>Just mark 'default y' on SIFIVE_OTP area of drivers/misc/Kconfig depends on
>SIFIVE SoC would select this driver so-that you no need to add impy
>SIFIVE_OTP here.

I am not sure if all SiFive SoC will contain SiFive OTP controller, so it's better not to make it default y.

If all Sifive SoCs contain OTP controller then I need to add another Kconfig option like "RISCV_SIFIVE" as shown below,
config SIFIVE_OTP
	default y if RISCV_SIFIVE

>
>Jagan.