Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751364AbdFBV2k (ORCPT ); Fri, 2 Jun 2017 17:28:40 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36803 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751184AbdFBV2i (ORCPT ); Fri, 2 Jun 2017 17:28:38 -0400 Subject: Re: [PATCH 2/9] [media] s5p-jpeg: Call jpeg_bound_align_image after qbuf To: Thierry Escande , Andrzej Pietrasiewicz , Mauro Carvalho Chehab References: <1496419376-17099-1-git-send-email-thierry.escande@collabora.com> <1496419376-17099-3-git-send-email-thierry.escande@collabora.com> Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org From: Jacek Anaszewski X-Enigmail-Draft-Status: N1110 Message-ID: <563c5112-93f7-7b05-1601-c3644a2111ce@gmail.com> Date: Fri, 2 Jun 2017 23:27:54 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.5.1 MIME-Version: 1.0 In-Reply-To: <1496419376-17099-3-git-send-email-thierry.escande@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2627 Lines: 65 Hi Thierry, Thanks for the patch. On 06/02/2017 06:02 PM, Thierry Escande wrote: > From: Tony K Nadackal > > When queuing an OUTPUT buffer for decoder, s5p_jpeg_parse_hdr() > function parses the input jpeg file and takes the width and height > parameters from its header. These new width/height values will be used > for the calculation of stride. HX_JPEG Hardware needs the width and > height values aligned on a 16 bits boundary. This width/height alignment > is handled in the s5p_jpeg_s_fmt_vid_cap() function during the S_FMT > ioctl call. > > But if user space calls the QBUF of OUTPUT buffer after the S_FMT of > CAPTURE buffer, these aligned values will be replaced by the values in > jpeg header. I assume that you may want to avoid re-setting the capture buf format when decoding a stream of JPEGs and you are certain that all of them have the same subsampling. Nonetheless, please keep in mind that in case of Exynos4x12 SoCs there is a risk of permanent decoder hangup if you'd try to decode to a YUV with lower subsampling than the one of input JPEG. s5p_jpeg_try_fmt_vid_cap() does a suitable adjustment to avoid the problem. I'd add a comment over this call to jpeg_bound_align_image() that resigning from executing S_FMT on capture buf for each JPEG image can result in a hardware hangup if forbidden decoding will be enforced. > If the width/height values of jpeg are not aligned, the > decoder output will be corrupted. So in this patch we call > jpeg_bound_align_image() to align the width/height values of Capture > buffer in s5p_jpeg_buf_queue(). > > Signed-off-by: Tony K Nadackal > Signed-off-by: Thierry Escande > --- > drivers/media/platform/s5p-jpeg/jpeg-core.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/media/platform/s5p-jpeg/jpeg-core.c b/drivers/media/platform/s5p-jpeg/jpeg-core.c > index 52dc794..6fb1ab4 100644 > --- a/drivers/media/platform/s5p-jpeg/jpeg-core.c > +++ b/drivers/media/platform/s5p-jpeg/jpeg-core.c > @@ -2523,6 +2523,13 @@ static void s5p_jpeg_buf_queue(struct vb2_buffer *vb) > q_data = &ctx->cap_q; > q_data->w = tmp.w; > q_data->h = tmp.h; > + > + jpeg_bound_align_image(ctx, &q_data->w, S5P_JPEG_MIN_WIDTH, > + S5P_JPEG_MAX_WIDTH, q_data->fmt->h_align, > + &q_data->h, S5P_JPEG_MIN_HEIGHT, > + S5P_JPEG_MAX_HEIGHT, q_data->fmt->v_align > + ); > + q_data->size = q_data->w * q_data->h * q_data->fmt->depth >> 3; > } > > v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf); > -- Best regards, Jacek Anaszewski