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charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 18 Dec 2020 at 12:23, Maxime Ripard wrote: > > Hi Dave, > > On Fri, Dec 18, 2020 at 11:37:50AM +0000, Dave Stevenson wrote: > > Hi Maxime > > > > On Thu, 10 Dec 2020 at 13:47, Maxime Ripard wrote: > > > > > > While the BCM2835 had the CEC clock derived from the HSM clock, the > > > BCM2711 has a dedicated parent clock for it. > > > > > > Let's introduce a separate clock for it so that we can handle both > > > cases. > > > > > > Signed-off-by: Maxime Ripard > > > --- > > > drivers/gpu/drm/vc4/vc4_hdmi.c | 9 ++++++++- > > > drivers/gpu/drm/vc4/vc4_hdmi.h | 1 + > > > 2 files changed, 9 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > index b93ee3e26e2b..0debd22bc992 100644 > > > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > > > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > @@ -145,7 +145,7 @@ static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) > > > * Set the clock divider: the hsm_clock rate and this divider > > > * setting will give a 40 kHz CEC clock. > > > */ > > > - clk_cnt = clk_get_rate(vc4_hdmi->hsm_clock) / CEC_CLOCK_FREQ; > > > + clk_cnt = clk_get_rate(vc4_hdmi->cec_clock) / CEC_CLOCK_FREQ; > > > value |= clk_cnt << VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT; > > > HDMI_WRITE(HDMI_CEC_CNTRL_1, value); > > > } > > > @@ -1740,6 +1740,7 @@ static int vc4_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->hsm_clock); > > > } > > > vc4_hdmi->audio_clock = vc4_hdmi->hsm_clock; > > > + vc4_hdmi->cec_clock = vc4_hdmi->hsm_clock; > > > > > > return 0; > > > } > > > @@ -1833,6 +1834,12 @@ static int vc5_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->audio_clock); > > > } > > > > > > + vc4_hdmi->cec_clock = devm_clk_get(dev, "cec"); > > > + if (IS_ERR(vc4_hdmi->cec_clock)) { > > > + DRM_ERROR("Failed to get CEC clock\n"); > > > + return PTR_ERR(vc4_hdmi->cec_clock); > > > + } > > > > Aren't we adding to the DT binding here and breaking backwards compatibility? > > Admittedly CEC didn't work before (and was masked out) for vc5, but do > > we need to worry about those with existing DT files that currently > > work happily? > > The DT compatibility is not a worry here: I made sure the CEC clock and > range were part of the binding since it's been introduced: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2e3725b05b785e73482a194b99bff3d5a1c85140 > > So we were not using it so far, but it was in the DT all along I guess I should have read it then :-) In which case Reviewed-by: Dave Stevenson From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD062C4361B for ; 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Fri, 18 Dec 2020 04:25:17 -0800 (PST) MIME-Version: 1.0 References: <20201210134648.272857-1-maxime@cerno.tech> <20201210134648.272857-9-maxime@cerno.tech> <20201218122334.tvdeslyyuus4hp4y@gilmour> In-Reply-To: <20201218122334.tvdeslyyuus4hp4y@gilmour> From: Dave Stevenson Date: Fri, 18 Dec 2020 12:25:00 +0000 Message-ID: Subject: Re: [PATCH 08/15] drm/vc4: hdmi: Introduce a CEC clock To: Maxime Ripard X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201218_072519_172950_F20662B4 X-CRM114-Status: GOOD ( 26.58 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Cooper , David Airlie , Marc Zyngier , Maarten Lankhorst , LKML , DRI Development , Eric Anholt , bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, Thomas Zimmermann , Hans Verkuil , Daniel Vetter , Thomas Gleixner , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, Linux Media Mailing List Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 18 Dec 2020 at 12:23, Maxime Ripard wrote: > > Hi Dave, > > On Fri, Dec 18, 2020 at 11:37:50AM +0000, Dave Stevenson wrote: > > Hi Maxime > > > > On Thu, 10 Dec 2020 at 13:47, Maxime Ripard wrote: > > > > > > While the BCM2835 had the CEC clock derived from the HSM clock, the > > > BCM2711 has a dedicated parent clock for it. > > > > > > Let's introduce a separate clock for it so that we can handle both > > > cases. > > > > > > Signed-off-by: Maxime Ripard > > > --- > > > drivers/gpu/drm/vc4/vc4_hdmi.c | 9 ++++++++- > > > drivers/gpu/drm/vc4/vc4_hdmi.h | 1 + > > > 2 files changed, 9 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > index b93ee3e26e2b..0debd22bc992 100644 > > > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > > > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > @@ -145,7 +145,7 @@ static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) > > > * Set the clock divider: the hsm_clock rate and this divider > > > * setting will give a 40 kHz CEC clock. > > > */ > > > - clk_cnt = clk_get_rate(vc4_hdmi->hsm_clock) / CEC_CLOCK_FREQ; > > > + clk_cnt = clk_get_rate(vc4_hdmi->cec_clock) / CEC_CLOCK_FREQ; > > > value |= clk_cnt << VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT; > > > HDMI_WRITE(HDMI_CEC_CNTRL_1, value); > > > } > > > @@ -1740,6 +1740,7 @@ static int vc4_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->hsm_clock); > > > } > > > vc4_hdmi->audio_clock = vc4_hdmi->hsm_clock; > > > + vc4_hdmi->cec_clock = vc4_hdmi->hsm_clock; > > > > > > return 0; > > > } > > > @@ -1833,6 +1834,12 @@ static int vc5_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->audio_clock); > > > } > > > > > > + vc4_hdmi->cec_clock = devm_clk_get(dev, "cec"); > > > + if (IS_ERR(vc4_hdmi->cec_clock)) { > > > + DRM_ERROR("Failed to get CEC clock\n"); > > > + return PTR_ERR(vc4_hdmi->cec_clock); > > > + } > > > > Aren't we adding to the DT binding here and breaking backwards compatibility? > > Admittedly CEC didn't work before (and was masked out) for vc5, but do > > we need to worry about those with existing DT files that currently > > work happily? > > The DT compatibility is not a worry here: I made sure the CEC clock and > range were part of the binding since it's been introduced: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2e3725b05b785e73482a194b99bff3d5a1c85140 > > So we were not using it so far, but it was in the DT all along I guess I should have read it then :-) In which case Reviewed-by: Dave Stevenson _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F08AC4361B for ; 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Fri, 18 Dec 2020 04:25:17 -0800 (PST) MIME-Version: 1.0 References: <20201210134648.272857-1-maxime@cerno.tech> <20201210134648.272857-9-maxime@cerno.tech> <20201218122334.tvdeslyyuus4hp4y@gilmour> In-Reply-To: <20201218122334.tvdeslyyuus4hp4y@gilmour> From: Dave Stevenson Date: Fri, 18 Dec 2020 12:25:00 +0000 Message-ID: Subject: Re: [PATCH 08/15] drm/vc4: hdmi: Introduce a CEC clock To: Maxime Ripard X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jason Cooper , David Airlie , Marc Zyngier , LKML , DRI Development , bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, Thomas Zimmermann , Hans Verkuil , Daniel Vetter , Thomas Gleixner , Mauro Carvalho Chehab , linux-arm-kernel@lists.infradead.org, Linux Media Mailing List Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Fri, 18 Dec 2020 at 12:23, Maxime Ripard wrote: > > Hi Dave, > > On Fri, Dec 18, 2020 at 11:37:50AM +0000, Dave Stevenson wrote: > > Hi Maxime > > > > On Thu, 10 Dec 2020 at 13:47, Maxime Ripard wrote: > > > > > > While the BCM2835 had the CEC clock derived from the HSM clock, the > > > BCM2711 has a dedicated parent clock for it. > > > > > > Let's introduce a separate clock for it so that we can handle both > > > cases. > > > > > > Signed-off-by: Maxime Ripard > > > --- > > > drivers/gpu/drm/vc4/vc4_hdmi.c | 9 ++++++++- > > > drivers/gpu/drm/vc4/vc4_hdmi.h | 1 + > > > 2 files changed, 9 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > index b93ee3e26e2b..0debd22bc992 100644 > > > --- a/drivers/gpu/drm/vc4/vc4_hdmi.c > > > +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c > > > @@ -145,7 +145,7 @@ static void vc4_hdmi_cec_update_clk_div(struct vc4_hdmi *vc4_hdmi) > > > * Set the clock divider: the hsm_clock rate and this divider > > > * setting will give a 40 kHz CEC clock. > > > */ > > > - clk_cnt = clk_get_rate(vc4_hdmi->hsm_clock) / CEC_CLOCK_FREQ; > > > + clk_cnt = clk_get_rate(vc4_hdmi->cec_clock) / CEC_CLOCK_FREQ; > > > value |= clk_cnt << VC4_HDMI_CEC_DIV_CLK_CNT_SHIFT; > > > HDMI_WRITE(HDMI_CEC_CNTRL_1, value); > > > } > > > @@ -1740,6 +1740,7 @@ static int vc4_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->hsm_clock); > > > } > > > vc4_hdmi->audio_clock = vc4_hdmi->hsm_clock; > > > + vc4_hdmi->cec_clock = vc4_hdmi->hsm_clock; > > > > > > return 0; > > > } > > > @@ -1833,6 +1834,12 @@ static int vc5_hdmi_init_resources(struct vc4_hdmi *vc4_hdmi) > > > return PTR_ERR(vc4_hdmi->audio_clock); > > > } > > > > > > + vc4_hdmi->cec_clock = devm_clk_get(dev, "cec"); > > > + if (IS_ERR(vc4_hdmi->cec_clock)) { > > > + DRM_ERROR("Failed to get CEC clock\n"); > > > + return PTR_ERR(vc4_hdmi->cec_clock); > > > + } > > > > Aren't we adding to the DT binding here and breaking backwards compatibility? > > Admittedly CEC didn't work before (and was masked out) for vc5, but do > > we need to worry about those with existing DT files that currently > > work happily? > > The DT compatibility is not a worry here: I made sure the CEC clock and > range were part of the binding since it's been introduced: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2e3725b05b785e73482a194b99bff3d5a1c85140 > > So we were not using it so far, but it was in the DT all along I guess I should have read it then :-) In which case Reviewed-by: Dave Stevenson _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel