From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH 1/2] drm/vc4: Skip ULPS latching when we're in that ULPS state already. Date: Mon, 30 Apr 2018 11:03:39 +0200 Message-ID: <20180430110339.29d217e7@bbrezillon> References: <20171031193258.17373-1-eric@anholt.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail.bootlin.com (mail.bootlin.com [62.4.15.54]) by gabe.freedesktop.org (Postfix) with ESMTP id 3362A89DEA for ; Mon, 30 Apr 2018 09:03:41 +0000 (UTC) In-Reply-To: <20171031193258.17373-1-eric@anholt.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Eric Anholt Cc: Thierry Reding , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org T24gVHVlLCAzMSBPY3QgMjAxNyAxMjozMjo1NyAtMDcwMApFcmljIEFuaG9sdCA8ZXJpY0Bhbmhv bHQubmV0PiB3cm90ZToKCj4gSXQgc2VlbXMgdGhhdCB0cnlpbmcgdG8gZ28gZnJvbSB1bmxhdGNo ZWQgdG8gdW5sYXRjaGVkIHdpbGwgdGltZSBvdXQKPiB3YWl0aW5nIGZvciBTVE9QLCBhbmQgd2Ug Y2FuIGp1c3Qgc2tpcCB0aGF0Lgo+IAo+IFNpZ25lZC1vZmYtYnk6IEVyaWMgQW5ob2x0IDxlcmlj QGFuaG9sdC5uZXQ+CgpSZXZpZXdlZC1ieTogQm9yaXMgQnJlemlsbG9uIDxib3Jpcy5icmV6aWxs b25AYm9vdGxpbi5jb20+Cgo+IC0tLQo+ICBkcml2ZXJzL2dwdS9kcm0vdmM0L3ZjNF9kc2kuYyB8 IDUgKysrKysKPiAgMSBmaWxlIGNoYW5nZWQsIDUgaW5zZXJ0aW9ucygrKQo+IAo+IGRpZmYgLS1n aXQgYS9kcml2ZXJzL2dwdS9kcm0vdmM0L3ZjNF9kc2kuYyBiL2RyaXZlcnMvZ3B1L2RybS92YzQv dmM0X2RzaS5jCj4gaW5kZXggOTQwODVmOGJjZDY4Li44YWE4OTc4MzUxMTggMTAwNjQ0Cj4gLS0t IGEvZHJpdmVycy9ncHUvZHJtL3ZjNC92YzRfZHNpLmMKPiArKysgYi9kcml2ZXJzL2dwdS9kcm0v dmM0L3ZjNF9kc2kuYwo+IEBAIC03NTMsNiArNzUzLDExIEBAIHN0YXRpYyB2b2lkIHZjNF9kc2lf dWxwcyhzdHJ1Y3QgdmM0X2RzaSAqZHNpLCBib29sIHVscHMpCj4gIAkJCSAoZHNpLT5sYW5lcyA+ IDIgPyBEU0kxX1NUQVRfUEhZX0QyX1NUT1AgOiAwKSB8Cj4gIAkJCSAoZHNpLT5sYW5lcyA+IDMg PyBEU0kxX1NUQVRfUEhZX0QzX1NUT1AgOiAwKSk7Cj4gIAlpbnQgcmV0Owo+ICsJYm9vbCB1bHBz X2N1cnJlbnRseV9lbmFibGVkID0gKERTSV9QT1JUX1JFQUQoUEhZX0FGRUMwKSAmCj4gKwkJCQkg ICAgICAgRFNJX1BPUlRfQklUKFBIWV9BRkVDMF9MQVRDSF9VTFBTKSk7Cj4gKwo+ICsJaWYgKHVs cHMgPT0gdWxwc19jdXJyZW50bHlfZW5hYmxlZCkKPiArCQlyZXR1cm47Cj4gIAo+ICAJRFNJX1BP UlRfV1JJVEUoU1RBVCwgc3RhdF91bHBzKTsKPiAgCURTSV9QT1JUX1dSSVRFKFBIWUMsIERTSV9Q T1JUX1JFQUQoUEhZQykgfCBwaHljX3VscHMpOwoKCgotLSAKQm9yaXMgQnJlemlsbG9uLCBCb290 bGluIChmb3JtZXJseSBGcmVlIEVsZWN0cm9ucykKRW1iZWRkZWQgTGludXggYW5kIEtlcm5lbCBl bmdpbmVlcmluZwpodHRwczovL2Jvb3RsaW4uY29tCl9fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxp c3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFu L2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752585AbeD3JDo (ORCPT ); Mon, 30 Apr 2018 05:03:44 -0400 Received: from mail.bootlin.com ([62.4.15.54]:43918 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752484AbeD3JDl (ORCPT ); Mon, 30 Apr 2018 05:03:41 -0400 Date: Mon, 30 Apr 2018 11:03:39 +0200 From: Boris Brezillon To: Eric Anholt Cc: dri-devel@lists.freedesktop.org, Thierry Reding , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] drm/vc4: Skip ULPS latching when we're in that ULPS state already. Message-ID: <20180430110339.29d217e7@bbrezillon> In-Reply-To: <20171031193258.17373-1-eric@anholt.net> References: <20171031193258.17373-1-eric@anholt.net> X-Mailer: Claws Mail 3.15.0-dirty (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 31 Oct 2017 12:32:57 -0700 Eric Anholt wrote: > It seems that trying to go from unlatched to unlatched will time out > waiting for STOP, and we can just skip that. > > Signed-off-by: Eric Anholt Reviewed-by: Boris Brezillon > --- > drivers/gpu/drm/vc4/vc4_dsi.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c > index 94085f8bcd68..8aa897835118 100644 > --- a/drivers/gpu/drm/vc4/vc4_dsi.c > +++ b/drivers/gpu/drm/vc4/vc4_dsi.c > @@ -753,6 +753,11 @@ static void vc4_dsi_ulps(struct vc4_dsi *dsi, bool ulps) > (dsi->lanes > 2 ? DSI1_STAT_PHY_D2_STOP : 0) | > (dsi->lanes > 3 ? DSI1_STAT_PHY_D3_STOP : 0)); > int ret; > + bool ulps_currently_enabled = (DSI_PORT_READ(PHY_AFEC0) & > + DSI_PORT_BIT(PHY_AFEC0_LATCH_ULPS)); > + > + if (ulps == ulps_currently_enabled) > + return; > > DSI_PORT_WRITE(STAT, stat_ulps); > DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) | phyc_ulps); -- Boris Brezillon, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com