All of lore.kernel.org
 help / color / mirror / Atom feed
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Michal Simek <michal.simek@amd.com>
Cc: linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH v1 3/3] spi: xilinx: Make num_chipselect 8-bit in the struct xspi_platform_data
Date: Fri, 8 Mar 2024 17:01:56 +0200	[thread overview]
Message-ID: <ZesoZKAZda7XkGhj@smile.fi.intel.com> (raw)
In-Reply-To: <ZesoP_XL7MQ_Wh51@smile.fi.intel.com>

On Fri, Mar 08, 2024 at 05:01:20PM +0200, Andy Shevchenko wrote:
> On Fri, Mar 08, 2024 at 03:00:55PM +0100, Michal Simek wrote:
> > On 3/8/24 14:55, Andy Shevchenko wrote:
> > > On Fri, Mar 08, 2024 at 02:48:04PM +0100, Michal Simek wrote:
> > > > On 3/8/24 14:31, Andy Shevchenko wrote:
> > > > > On Fri, Mar 08, 2024 at 09:20:23AM +0100, Michal Simek wrote:
> > > > > > On 3/7/24 16:43, Andy Shevchenko wrote:

...

> > > > > > >     struct xspi_platform_data {
> > > > > > > -	u16 num_chipselect;
> > > > > > > -	u8 bits_per_word;
> > > > > > > -	struct spi_board_info *devices;
> > > > > > > -	u8 num_devices;
> > > > > > >     	bool force_irq;
> > > > > > > +	u8 num_chipselect;
> > > > > > > +	u8 bits_per_word;
> > > > > > > +	u8 num_devices;
> > > > > > 
> > > > > > all above have 32bits. It means on 64bit cpu you have 32bit gap here.
> > > > > 
> > > > > > > +	struct spi_board_info *devices;
> > > > > 
> > > > > On all architectures? I mean do all 64-bit architecture ABIs _require_
> > > > > the pointer to be aligned at 8-byte boundary? Even if so, the struct
> > > > > itself can be aligned on 4-byte boundary.
> > > > 
> > > > I am not able to tell if toolchain enforce 8byte alignment by default/by
> > > > setup on all 64bit systems.
> > > > I am using pahole to check this which was recommended by Greg in past which
> > > > reports gap in the middle.
> > > 
> > > I see, thanks for explanation.
> > > 
> > > Yes, it's likely that in some cases it will be a gap on 64-bit platforms, but
> > > after this patch no gap on 32-bit. Do you still want me to reshuffle that as
> > > you suggested?
> > 
> > Yes I would prefer to do that change when you are doing cleanup.
> 
> Can you give your tag?

I mean for the other patch, not this one :-)

> Then I prepare a new version with addressed comments
> against last patch.

-- 
With Best Regards,
Andy Shevchenko



WARNING: multiple messages have this Message-ID (diff)
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Michal Simek <michal.simek@amd.com>
Cc: linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH v1 3/3] spi: xilinx: Make num_chipselect 8-bit in the struct xspi_platform_data
Date: Fri, 8 Mar 2024 17:01:56 +0200	[thread overview]
Message-ID: <ZesoZKAZda7XkGhj@smile.fi.intel.com> (raw)
In-Reply-To: <ZesoP_XL7MQ_Wh51@smile.fi.intel.com>

On Fri, Mar 08, 2024 at 05:01:20PM +0200, Andy Shevchenko wrote:
> On Fri, Mar 08, 2024 at 03:00:55PM +0100, Michal Simek wrote:
> > On 3/8/24 14:55, Andy Shevchenko wrote:
> > > On Fri, Mar 08, 2024 at 02:48:04PM +0100, Michal Simek wrote:
> > > > On 3/8/24 14:31, Andy Shevchenko wrote:
> > > > > On Fri, Mar 08, 2024 at 09:20:23AM +0100, Michal Simek wrote:
> > > > > > On 3/7/24 16:43, Andy Shevchenko wrote:

...

> > > > > > >     struct xspi_platform_data {
> > > > > > > -	u16 num_chipselect;
> > > > > > > -	u8 bits_per_word;
> > > > > > > -	struct spi_board_info *devices;
> > > > > > > -	u8 num_devices;
> > > > > > >     	bool force_irq;
> > > > > > > +	u8 num_chipselect;
> > > > > > > +	u8 bits_per_word;
> > > > > > > +	u8 num_devices;
> > > > > > 
> > > > > > all above have 32bits. It means on 64bit cpu you have 32bit gap here.
> > > > > 
> > > > > > > +	struct spi_board_info *devices;
> > > > > 
> > > > > On all architectures? I mean do all 64-bit architecture ABIs _require_
> > > > > the pointer to be aligned at 8-byte boundary? Even if so, the struct
> > > > > itself can be aligned on 4-byte boundary.
> > > > 
> > > > I am not able to tell if toolchain enforce 8byte alignment by default/by
> > > > setup on all 64bit systems.
> > > > I am using pahole to check this which was recommended by Greg in past which
> > > > reports gap in the middle.
> > > 
> > > I see, thanks for explanation.
> > > 
> > > Yes, it's likely that in some cases it will be a gap on 64-bit platforms, but
> > > after this patch no gap on 32-bit. Do you still want me to reshuffle that as
> > > you suggested?
> > 
> > Yes I would prefer to do that change when you are doing cleanup.
> 
> Can you give your tag?

I mean for the other patch, not this one :-)

> Then I prepare a new version with addressed comments
> against last patch.

-- 
With Best Regards,
Andy Shevchenko



_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2024-03-08 15:02 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-07 15:43 [PATCH v1 0/3] spi: xilinx: Massage xilinx_spi.h Andy Shevchenko
2024-03-07 15:43 ` Andy Shevchenko
2024-03-07 15:43 ` [PATCH v1 1/3] spi: xilinx: Fix kernel documentation in the xilinx_spi.h Andy Shevchenko
2024-03-07 15:43   ` Andy Shevchenko
2024-03-08  8:22   ` Michal Simek
2024-03-08  8:22     ` Michal Simek
2024-03-07 15:43 ` [PATCH v1 2/3] spi: xilinx: Add necessary inclusion and forward declaration Andy Shevchenko
2024-03-07 15:43   ` Andy Shevchenko
2024-03-08  8:21   ` Michal Simek
2024-03-08  8:21     ` Michal Simek
2024-03-08 13:56     ` Andy Shevchenko
2024-03-08 13:56       ` Andy Shevchenko
2024-03-08 14:02       ` Michal Simek
2024-03-08 14:02         ` Michal Simek
2024-03-08 15:00         ` Andy Shevchenko
2024-03-08 15:00           ` Andy Shevchenko
2024-03-08 15:27           ` Michal Simek
2024-03-08 15:27             ` Michal Simek
2024-03-07 15:43 ` [PATCH v1 3/3] spi: xilinx: Make num_chipselect 8-bit in the struct xspi_platform_data Andy Shevchenko
2024-03-07 15:43   ` Andy Shevchenko
2024-03-08  8:20   ` Michal Simek
2024-03-08  8:20     ` Michal Simek
2024-03-08 13:31     ` Andy Shevchenko
2024-03-08 13:31       ` Andy Shevchenko
2024-03-08 13:48       ` Michal Simek
2024-03-08 13:48         ` Michal Simek
2024-03-08 13:55         ` Andy Shevchenko
2024-03-08 13:55           ` Andy Shevchenko
2024-03-08 14:00           ` Michal Simek
2024-03-08 14:00             ` Michal Simek
2024-03-08 15:01             ` Andy Shevchenko
2024-03-08 15:01               ` Andy Shevchenko
2024-03-08 15:01               ` Andy Shevchenko [this message]
2024-03-08 15:01                 ` Andy Shevchenko

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=ZesoZKAZda7XkGhj@smile.fi.intel.com \
    --to=andriy.shevchenko@linux.intel.com \
    --cc=broonie@kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-spi@vger.kernel.org \
    --cc=michal.simek@amd.com \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.