From: "Marek Behún" <kabel@kernel.org>
To: "Pali Rohár" <pali@kernel.org>
Cc: Stefan Roese <sr@denx.de>, u-boot@lists.denx.de
Subject: Re: [PATCH 2/2] arm: mvebu: turris_omnia: Add support for design with SW reset signals
Date: Mon, 1 Aug 2022 17:49:19 +0200 [thread overview]
Message-ID: <20220801174919.6982e055@dellmb> (raw)
In-Reply-To: <20220729112907.8207-2-pali@kernel.org>
On Fri, 29 Jul 2022 13:29:07 +0200
Pali Rohár <pali@kernel.org> wrote:
> New Turris Omnia HW board revision requires that software controls
> peripheral reset signals, namely PERST# signals on mPCIe slots, ethernet
> phy reset and lan switch reset. Those pins are connected to MCU controlled
> by MCU i2c API as GPIOs. On new HW board revision those pins stay in reset
> after board reset and software has to release these peripherals from reset
> manually. MCU announce this requirement by FEAT_PERIPH_MCU bit in
> CMD_GET_FEATURES command.
>
> On older HW board revisions when FEAT_PERIPH_MCU is not announced, all
> those reset signals are automatically released after board finish reset.
>
> Detect FEAT_PERIPH_MCU bit in board_fix_fdt() and ft_board_setup()
> functions and insert into device tree blob pcie "reset-gpios" and eth phy
> "phy-reset-gpios" properties with corresponding MCU gpio definitions.
> PCIe and eth PHY drivers then automatically release resets during device
> initialization. Both U-Boot and Linux kernel drivers support those device
> tree reset properties.
>
> Initialization of lan switch on new HW board revision is more complicated.
> Switch strapping pins are shared with switch RGMII pins. And strapping pins
> must be in specific configuration after releasing switch reset. Due to pin
> sharing, it is first required to switch A385 side of switch pins into GPIO
> mode, set strapping configuration, release switch from reset and after that
> switch A385 pins back to RGMII mode.
>
> Because this complicated setup is not supported by switch DSA drivers and
> cannot be expressed easily in device tree, implement it manually in SPL
> function spl_board_init(). So in proper U-Boot and OS/kernel would be lan
> switch initialized and be in same configuration like it was on old HW board
> revisions (where reset sequence did those steps at hardware level).
>
> Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Marek Behún <kabel@kernel.org>
next prev parent reply other threads:[~2022-08-01 15:49 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-29 11:29 [PATCH 1/2] arm: mvebu: turris_omnia: Show MCU type in show_board_info() Pali Rohár
2022-07-29 11:29 ` [PATCH 2/2] arm: mvebu: turris_omnia: Add support for design with SW reset signals Pali Rohár
2022-08-01 11:58 ` Stefan Roese
2022-08-01 12:19 ` Pali Rohár
2022-08-01 15:49 ` Marek Behún [this message]
2022-08-09 11:32 ` Stefan Roese
2022-08-01 11:56 ` [PATCH 1/2] arm: mvebu: turris_omnia: Show MCU type in show_board_info() Stefan Roese
2022-08-01 15:49 ` Marek Behún
2022-08-09 11:32 ` Stefan Roese
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220801174919.6982e055@dellmb \
--to=kabel@kernel.org \
--cc=pali@kernel.org \
--cc=sr@denx.de \
--cc=u-boot@lists.denx.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox