linux-kernel - Re: [PATCH 02/16] gpu: ipu-cpmem: Add ipu_cpmem_set_uv

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1468586744.7213.32.camel@pengutronix.de>
Date:	Fri, 15 Jul 2016 14:45:44 +0200
From:	Philipp Zabel <p.zabel@...gutronix.de>
To:	Steve Longerbeam <steve_longerbeam@...tor.com>
Cc:	Steve Longerbeam <slongerbeam@...il.com>,
	dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 02/16] gpu: ipu-cpmem: Add ipu_cpmem_set_uv_offset()

Am Mittwoch, den 13.07.2016, 15:54 -0700 schrieb Steve Longerbeam:
> Hi Philipp,
> 
> On 07/08/2016 10:34 AM, Philipp Zabel wrote:
> > Am Donnerstag, den 07.07.2016, 16:03 -0700 schrieb Steve Longerbeam:
> >> Adds ipu_cpmem_set_uv_offset(), to set planar U/V offsets.
> >>
> >> Signed-off-by: Steve Longerbeam <steve_longerbeam@...tor.com>
> >> ---
> >>  drivers/gpu/ipu-v3/ipu-cpmem.c | 7 +++++++
> >>  include/video/imx-ipu-v3.h     | 1 +
> >>  2 files changed, 8 insertions(+)
> >>
> >> diff --git a/drivers/gpu/ipu-v3/ipu-cpmem.c b/drivers/gpu/ipu-v3/ipu-cpmem.c
> >> index 6494a4d..a36c35e 100644
> >> --- a/drivers/gpu/ipu-v3/ipu-cpmem.c
> >> +++ b/drivers/gpu/ipu-v3/ipu-cpmem.c
> >> @@ -253,6 +253,13 @@ void ipu_cpmem_set_buffer(struct ipuv3_channel *ch, int bufnum, dma_addr_t buf)
> >>  }
> >>  EXPORT_SYMBOL_GPL(ipu_cpmem_set_buffer);
> >>  
> >> +void ipu_cpmem_set_uv_offset(struct ipuv3_channel *ch, u32 u_off, u32 v_off)
> >> +{
> >> +	ipu_ch_param_write_field(ch, IPU_FIELD_UBO, u_off / 8);
> >> +	ipu_ch_param_write_field(ch, IPU_FIELD_VBO, v_off / 8);
> >> +}
> >> +EXPORT_SYMBOL_GPL(ipu_cpmem_set_uv_offset);
> >> +
> > I'd prefer to avoid too much duplication in the API. Is there a reason
> > you can't use ipu_cpmem_set_yuv_planar_full?
> 
> I could, but it would be cumbersome. ipu_cpmem_set_uv_offset() is being
> called when kicking off a new tile conversion, and the stride length would
> have to be calculated all over again if I were to use ipu_cpmem_set_yuv_planar_ful().
> When kicking off a new tile conversion, the stride doesn't change, only the
> tile's buffer address, and U/V offsets for planar, need to be updated.

Ok. We'll have to change tile width and height as well, but the stride
indeed is constant.

regards
Philipp