From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: gregkh <gregkh@linuxfoundation.org>,
smohanad@codeaurora.org, Jeffrey Hugo <jhugo@codeaurora.org>,
Kalle Valo <kvalo@codeaurora.org>,
Bjorn Andersson <bjorn.andersson@linaro.org>,
hemantk@codeaurora.org,
linux-arm-msm <linux-arm-msm@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Jonathan Corbet <corbet@lwn.net>,
"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>
Subject: Re: [PATCH 01/16] docs: Add documentation for MHI bus
Date: Thu, 23 Jan 2020 19:00:10 +0530 [thread overview]
Message-ID: <20200123133010.GB11366@mani> (raw)
In-Reply-To: <CAK8P3a1z7mVEpxbk47Q3A-tLDhqHUid2_S4tE3NQuf_2_UCOcg@mail.gmail.com>
On Thu, Jan 23, 2020 at 02:19:51PM +0100, Arnd Bergmann wrote:
> On Thu, Jan 23, 2020 at 2:10 PM Manivannan Sadhasivam
> <manivannan.sadhasivam@linaro.org> wrote:
> >
> > On Thu, Jan 23, 2020 at 01:58:22PM +0100, Arnd Bergmann wrote:
> > > On Thu, Jan 23, 2020 at 12:18 PM Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> wrote:
> > >
> > > I don't see any callers of mhi_register_controller(). Did I just miss it or did
> > > you not post one? I'm particularly interested in where the configuration comes
> > > from, is this hardcoded in the driver, or parsed from firmware or from registers
> > > in the hardware itself?
> > >
> >
> > I have not included the controller driver in this patchset. But you can take a
> > look at the ath11k controller driver here:
> > https://git.linaro.org/people/manivannan.sadhasivam/linux.git/tree/drivers/net/wireless/ath/ath11k/mhi.c?h=ath11k-qca6390-mhi#n13
> >
> > So the configuration comes from the static structures defined in the controller
> > driver. Earlier revision derived the configuration from devicetree but there are
> > many cases where this MHI bus is being used in non DT environments like x86.
> > So inorder to be platform agnostic, we chose static declaration method.
> >
> > In future we can add DT/ACPI support for the applicable parameters.
>
> What determines the configuration? Is this always something that is fixed
> in hardware, or can some of the properties be changed based on what
> firmware runs the device?
>
AFAIK, these configurations are fixed in hardware (this could come from
the firmware I'm not sure but they don't change with firmware revisions
for sure)
The reason for defining in the driver itself implies that these don't
change. But I'll confirm this with Qcom folks.
Thanks,
Mani
> If this is determined by the firmware, maybe the configuration would also
> need to be loaded from the file that contains the firmware, which in turn
> could be a blob in DT.
>
> Arnd
next prev parent reply other threads:[~2020-01-23 13:30 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200123111836.7414-1-manivannan.sadhasivam@linaro.org>
2020-01-23 11:18 ` [PATCH 01/16] docs: Add documentation for MHI bus Manivannan Sadhasivam
2020-01-23 12:58 ` Arnd Bergmann
2020-01-23 13:10 ` Manivannan Sadhasivam
2020-01-23 13:19 ` Arnd Bergmann
2020-01-23 13:30 ` Manivannan Sadhasivam [this message]
2020-01-23 14:52 ` Jeffrey Hugo
2020-01-23 16:41 ` Jeffrey Hugo
2020-01-27 12:02 ` Manivannan Sadhasivam
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=20200123133010.GB11366@mani \
--to=manivannan.sadhasivam@linaro.org \
--cc=arnd@arndb.de \
--cc=bjorn.andersson@linaro.org \
--cc=corbet@lwn.net \
--cc=gregkh@linuxfoundation.org \
--cc=hemantk@codeaurora.org \
--cc=jhugo@codeaurora.org \
--cc=kvalo@codeaurora.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=smohanad@codeaurora.org \
/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;
as well as URLs for NNTP newsgroup(s).