From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Subject: Re: [PATCH v2] drm/stm: drv: Improve data transfers Date: Tue, 30 Jan 2018 16:58:07 +0200 Message-ID: <3365044.AohtTD8A6l@avalon> References: <20180130104200.21602-1-philippe.cornu@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from galahad.ideasonboard.com (galahad.ideasonboard.com [IPv6:2001:4b98:dc2:45:216:3eff:febb:480d]) by gabe.freedesktop.org (Postfix) with ESMTPS id 837C56E781 for ; Tue, 30 Jan 2018 14:57:53 +0000 (UTC) In-Reply-To: <20180130104200.21602-1-philippe.cornu@st.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Philippe Cornu Cc: Maxime Coquelin , Alexandre Torgue , David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Yannick Fertre , Fabien Dessenne , Mickael Reulier , Vincent Abriou , Ludovic Barre List-Id: dri-devel@lists.freedesktop.org SGkgUGhpbGlwcGUsCgpUaGFuayB5b3UgZm9yIHRoZSBwYXRjaC4KCk9uIFR1ZXNkYXksIDMwIEph bnVhcnkgMjAxOCAxMjo0MjowMCBFRVQgUGhpbGlwcGUgQ29ybnUgd3JvdGU6Cj4gVG8gb3B0aW1p emUgZGF0YSB0cmFuc2ZlcnMsIGFsaWduIHBpdGNoIG9uIDEyOCBieXRlcyAmIGhlaWdodAo+IG9u IDQgYnl0ZXMuIFRoaXMgb3B0aW1pemF0aW9uIGlzIG5vdCBhcHBsaWNhYmxlIG9uIGh3IHdpdGhv dXQgTU1VLgo+IAo+IFNpZ25lZC1vZmYtYnk6IFlhbm5pY2sgRmVydHJlIDx5YW5uaWNrLmZlcnRy ZUBzdC5jb20+Cj4gU2lnbmVkLW9mZi1ieTogVmluY2VudCBBYnJpb3UgPHZpbmNlbnQuYWJyaW91 QHN0LmNvbT4KPiBTaWduZWQtb2ZmLWJ5OiBQaGlsaXBwZSBDb3JudSA8cGhpbGlwcGUuY29ybnVA c3QuY29tPgo+IC0tLQo+IENoYW5nZXMgaW4gdjI6IFJlbmFtZSBzdG1fZHVtYl9jcmVhdGUoKSB0 byBzdG1fZ2VtX2NtYV9kdW1iX2NyZWF0ZSgpIGFuZAo+ICAgbW92ZSBDT05GSUdfTU1VIGluc2lk ZSB0aGUgZnVuY3Rpb24gZm9sbG93aW5nIGNvbW1lbnRzIGZyb20gQmVuamFtaW4KPiAgIEdhaWdu YXJkLgo+IAo+ICBkcml2ZXJzL2dwdS9kcm0vc3RtL2Rydi5jIHwgMjAgKysrKysrKysrKysrKysr KysrKy0KPiAgMSBmaWxlIGNoYW5nZWQsIDE5IGluc2VydGlvbnMoKyksIDEgZGVsZXRpb24oLSkK PiAKPiBkaWZmIC0tZ2l0IGEvZHJpdmVycy9ncHUvZHJtL3N0bS9kcnYuYyBiL2RyaXZlcnMvZ3B1 L2RybS9zdG0vZHJ2LmMKPiBpbmRleCA4ZmU5NTRjMjdmYmEuLjhiYzdlODQxOGI4ZCAxMDA2NDQK PiAtLS0gYS9kcml2ZXJzL2dwdS9kcm0vc3RtL2Rydi5jCj4gKysrIGIvZHJpdmVycy9ncHUvZHJt L3N0bS9kcnYuYwo+IEBAIC0zMSw2ICszMSwyNCBAQCBzdGF0aWMgY29uc3Qgc3RydWN0IGRybV9t b2RlX2NvbmZpZ19mdW5jcwo+IGRydl9tb2RlX2NvbmZpZ19mdW5jcyA9IHsgLmF0b21pY19jb21t aXQgPSBkcm1fYXRvbWljX2hlbHBlcl9jb21taXQsCj4gIH07Cj4gCj4gK3N0YXRpYyBpbnQgc3Rt X2dlbV9jbWFfZHVtYl9jcmVhdGUoc3RydWN0IGRybV9maWxlICpmaWxlLAo+ICsJCQkJICAgc3Ry dWN0IGRybV9kZXZpY2UgKmRldiwKPiArCQkJCSAgIHN0cnVjdCBkcm1fbW9kZV9jcmVhdGVfZHVt YiAqYXJncykKPiArewo+ICsjaWZkZWYgQ09ORklHX01NVQo+ICsJdW5zaWduZWQgaW50IG1pbl9w aXRjaCA9IERJVl9ST1VORF9VUChhcmdzLT53aWR0aCAqIGFyZ3MtPmJwcCwgOCk7Cj4gKwo+ICsJ LyoKPiArCSAqIGluIG9yZGVyIHRvIG9wdGltaXplIGRhdGEgdHJhbnNmZXIsIHBpdGNoIGlzIGFs aWduZWQgb24KPiArCSAqIDEyOCBieXRlcywgaGVpZ2h0IGlzIGFsaWduZWQgb24gNCBieXRlcwo+ ICsJICovCj4gKwlhcmdzLT5waXRjaCA9IHJvdW5kdXAobWluX3BpdGNoLCAxMjgpOwo+ICsJYXJn cy0+aGVpZ2h0ID0gcm91bmR1cChhcmdzLT5oZWlnaHQsIDQpOwo+ICsjZW5kaWYKPiArCj4gKwly ZXR1cm4gZHJtX2dlbV9jbWFfZHVtYl9jcmVhdGVfaW50ZXJuYWwoZmlsZSwgZGV2LCBhcmdzKTsK CkluIHRoZSAhQ09ORklHX01NVSBjYXNlIHlvdSBub3cgYnlwYXNzIHRoZSBwaXRjaCBhbmQgc2l6 ZSBjYWxjdWxhdGlvbnMgCnBlcmZvcm1lZCBieSBkcm1fZ2VtX2NtYV9kdW1iX2NyZWF0ZSgpLCBh bGxvd2luZyB1c2Vyc3BhY2UgdG8gYWxsb2NhdGUgCmFyYml0cmFyaWx5IGxhcmdlIGJ1ZmZlcnMu IElzIHRoYXQgaW50ZW50aW9uYWwgPwoKPiArfQo+ICsKPiAgREVGSU5FX0RSTV9HRU1fQ01BX0ZP UFMoZHJ2X2RyaXZlcl9mb3BzKTsKPiAKPiAgc3RhdGljIHN0cnVjdCBkcm1fZHJpdmVyIGRydl9k cml2ZXIgPSB7Cj4gQEAgLTQ0LDcgKzYyLDcgQEAgc3RhdGljIHN0cnVjdCBkcm1fZHJpdmVyIGRy dl9kcml2ZXIgPSB7Cj4gIAkubWlub3IgPSAwLAo+ICAJLnBhdGNobGV2ZWwgPSAwLAo+ICAJLmZv cHMgPSAmZHJ2X2RyaXZlcl9mb3BzLAo+IC0JLmR1bWJfY3JlYXRlID0gZHJtX2dlbV9jbWFfZHVt Yl9jcmVhdGUsCj4gKwkuZHVtYl9jcmVhdGUgPSBzdG1fZ2VtX2NtYV9kdW1iX2NyZWF0ZSwKPiAg CS5wcmltZV9oYW5kbGVfdG9fZmQgPSBkcm1fZ2VtX3ByaW1lX2hhbmRsZV90b19mZCwKPiAgCS5w cmltZV9mZF90b19oYW5kbGUgPSBkcm1fZ2VtX3ByaW1lX2ZkX3RvX2hhbmRsZSwKPiAgCS5nZW1f ZnJlZV9vYmplY3RfdW5sb2NrZWQgPSBkcm1fZ2VtX2NtYV9mcmVlX29iamVjdCwKCi0tIApSZWdh cmRzLAoKTGF1cmVudCBQaW5jaGFydAoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX18KZHJpLWRldmVsIG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJl ZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGlu Zm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752865AbeA3O5x (ORCPT ); Tue, 30 Jan 2018 09:57:53 -0500 Received: from galahad.ideasonboard.com ([185.26.127.97]:45492 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752786AbeA3O5w (ORCPT ); Tue, 30 Jan 2018 09:57:52 -0500 From: Laurent Pinchart To: Philippe Cornu Cc: Yannick Fertre , Benjamin Gaignard , Vincent Abriou , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Archit Taneja , Andrzej Hajda , Fabien Dessenne , Mickael Reulier , Ludovic Barre , Alexandre Torgue , Maxime Coquelin Subject: Re: [PATCH v2] drm/stm: drv: Improve data transfers Date: Tue, 30 Jan 2018 16:58:07 +0200 Message-ID: <3365044.AohtTD8A6l@avalon> Organization: Ideas on Board Oy In-Reply-To: <20180130104200.21602-1-philippe.cornu@st.com> References: <20180130104200.21602-1-philippe.cornu@st.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Philippe, Thank you for the patch. On Tuesday, 30 January 2018 12:42:00 EET Philippe Cornu wrote: > To optimize data transfers, align pitch on 128 bytes & height > on 4 bytes. This optimization is not applicable on hw without MMU. > > Signed-off-by: Yannick Fertre > Signed-off-by: Vincent Abriou > Signed-off-by: Philippe Cornu > --- > Changes in v2: Rename stm_dumb_create() to stm_gem_cma_dumb_create() and > move CONFIG_MMU inside the function following comments from Benjamin > Gaignard. > > drivers/gpu/drm/stm/drv.c | 20 +++++++++++++++++++- > 1 file changed, 19 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/stm/drv.c b/drivers/gpu/drm/stm/drv.c > index 8fe954c27fba..8bc7e8418b8d 100644 > --- a/drivers/gpu/drm/stm/drv.c > +++ b/drivers/gpu/drm/stm/drv.c > @@ -31,6 +31,24 @@ static const struct drm_mode_config_funcs > drv_mode_config_funcs = { .atomic_commit = drm_atomic_helper_commit, > }; > > +static int stm_gem_cma_dumb_create(struct drm_file *file, > + struct drm_device *dev, > + struct drm_mode_create_dumb *args) > +{ > +#ifdef CONFIG_MMU > + unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8); > + > + /* > + * in order to optimize data transfer, pitch is aligned on > + * 128 bytes, height is aligned on 4 bytes > + */ > + args->pitch = roundup(min_pitch, 128); > + args->height = roundup(args->height, 4); > +#endif > + > + return drm_gem_cma_dumb_create_internal(file, dev, args); In the !CONFIG_MMU case you now bypass the pitch and size calculations performed by drm_gem_cma_dumb_create(), allowing userspace to allocate arbitrarily large buffers. Is that intentional ? > +} > + > DEFINE_DRM_GEM_CMA_FOPS(drv_driver_fops); > > static struct drm_driver drv_driver = { > @@ -44,7 +62,7 @@ static struct drm_driver drv_driver = { > .minor = 0, > .patchlevel = 0, > .fops = &drv_driver_fops, > - .dumb_create = drm_gem_cma_dumb_create, > + .dumb_create = stm_gem_cma_dumb_create, > .prime_handle_to_fd = drm_gem_prime_handle_to_fd, > .prime_fd_to_handle = drm_gem_prime_fd_to_handle, > .gem_free_object_unlocked = drm_gem_cma_free_object, -- Regards, Laurent Pinchart