From mboxrd@z Thu Jan 1 00:00:00 1970 From: icenowy-h8G6r0blFSE@public.gmane.org Subject: Re: [PATCH v2 07/11] drm: sun4i: add support for the TV encoder in H3 SoC Date: Sun, 11 Jun 2017 14:43:42 +0800 Message-ID: <362bb72d74cd7181ae02dbf73b0e724e@aosc.io> References: <20170604160149.30230-1-icenowy@aosc.io> <20170604160149.30230-8-icenowy@aosc.io> <20170607093845.cu5kk55nj72roysf@flea.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20170607093845.cu5kk55nj72roysf-ZC1Zs529Oq4@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Maxime Ripard Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, =?UTF-8?Q?Jernej_=C5=A0krabec?= , linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, Chen-Yu Tsai , Rob Herring , linux-clk-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org 在 2017-06-07 17:38，Maxime Ripard 写道： > On Mon, Jun 05, 2017 at 12:01:45AM +0800, Icenowy Zheng wrote: >> Allwinner H3 features a TV encoder similar to the one in earlier SoCs, >> but has a internal fixed clock divider that divides the TCON1 clock >> (called TVE clock in datasheet) by 11. >> >> Add support for it. >> >> Signed-off-by: Icenowy Zheng >> --- >> Changes in v2: >> - Quirk part rewritten. >> >> drivers/gpu/drm/sun4i/sun4i_tv.c | 35 >> ++++++++++++++++++++++++++++++++++- >> 1 file changed, 34 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/sun4i/sun4i_tv.c >> b/drivers/gpu/drm/sun4i/sun4i_tv.c >> index 338b9e5bb2a3..b9ff6d5ea67a 100644 >> --- a/drivers/gpu/drm/sun4i/sun4i_tv.c >> +++ b/drivers/gpu/drm/sun4i/sun4i_tv.c >> @@ -13,6 +13,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -169,14 +170,21 @@ struct tv_mode { >> const struct resync_parameters *resync_params; >> }; >> >> +struct sun4i_tv_quirks { >> + int fixed_divider; >> +}; >> + >> struct sun4i_tv { >> struct drm_connector connector; >> struct drm_encoder encoder; >> >> struct clk *clk; >> + struct clk *mod_clk; >> struct regmap *regs; >> struct reset_control *reset; >> >> + const struct sun4i_tv_quirks *quirks; >> + >> struct sun4i_drv *drv; >> }; >> >> @@ -391,6 +399,12 @@ static void sun4i_tv_mode_set(struct drm_encoder >> *encoder, >> struct sun4i_tcon *tcon = crtc->tcon; >> const struct tv_mode *tv_mode = sun4i_tv_find_tv_by_mode(mode); >> >> + if (tv->quirks->fixed_divider) { >> + DRM_DEBUG_DRIVER("Applying fixed divider %d on TVE clock\n", >> + tv->quirks->fixed_divider); >> + mode->crtc_clock *= tv->quirks->fixed_divider; >> + } >> + > > You're not allowed to change the mode in mode_set, and you shouldn't > even change it. The output pixel clock is still 27MHz. > > You should implement that using the states, as we discussed already. After reading the comments at include/drm/drm_modeset_helper_vtables.h, I think the atomic_check function is allowed to directly change the adjust_mode of crtc_state. And according to other comments at include/drm/drm_modes.h, the crtc_clock in adjust_mode should be the clock to be really feed to the hardware. So I think I can just change this in atomic_check. However, the mode_set function of sun4i_tv seems to be not regarding adjusted_mode and still use original mode. So my current design is: - Multiply adjusted_mode in atomic_check. - Feed adjust_mode to TCON code in mode_set function. Is this proper? (From my own understanding to the comments I think so.) > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html