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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EB16BE77188 for ; Tue, 31 Dec 2024 13:54:57 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 4DC9510E06B; Tue, 31 Dec 2024 13:54:57 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="BhDD9XRx"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2F2F710E06B for ; Tue, 31 Dec 2024 13:54:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1735653296; x=1767189296; h=from:to:subject:in-reply-to:references:date:message-id: mime-version:content-transfer-encoding; bh=xn6nzFe407lgSU+9URl0DY39GvFT7kcP1ae7WFLctiY=; b=BhDD9XRxO+lGWVEsoM0iNbH0X93gwFxXF7wnoW7BkBOm+H6SA0mWrKkW MHSLepre5zzEVsOp4Fh311bVLvastoyZNEWGRfhxHYvUM78UuFBxnpDUD 5QCfbKuNymmLESZYH7i3OnO24FyScFjHXSDok9KhzYQNTOcDRhO8c/kCc P4fOsYMyMp7i8FfXUJIr/SRQIABmLlBcjRumX1YdI6Io8XNIHQ2CiWMCB XET/i6nadKeUPNm2XdTgAaeEIjsrMTPrRhe2xRskqIDjogPapzNHDKFhs NwTUOUL2zM3FXA7AypHkPWAgqdm3pPOS8mSrZ3Cl2937HKUKFAEoJ7wwF A==; X-CSE-ConnectionGUID: Ng1YT8sbTxWwsOTEysCOhA== X-CSE-MsgGUID: JLJHJIZ+ScGwIXVS1CAZSQ== X-IronPort-AV: E=McAfee;i="6700,10204,11302"; a="47295307" X-IronPort-AV: E=Sophos;i="6.12,279,1728975600"; d="scan'208";a="47295307" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Dec 2024 05:54:56 -0800 X-CSE-ConnectionGUID: jg0GdNd0QpSuKbW38O5ALg== X-CSE-MsgGUID: y2SuIAqOTYeU8pDvfwZhJg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,279,1728975600"; d="scan'208";a="101561500" Received: from iklimasz-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.246.180]) by fmviesa009-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Dec 2024 05:54:54 -0800 From: Jani Nikula To: "Vodapalli, Ravi Kumar" , intel-gfx@lists.freedesktop.org Subject: Re: [PATCH 2/2] drm/i915/lttpr: Enable Extended Wake Timeout In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20241213060317.2674290-1-suraj.kandpal@intel.com> <20241213060317.2674290-3-suraj.kandpal@intel.com> Date: Tue, 31 Dec 2024 15:54:51 +0200 Message-ID: <87ikr0nej8.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Tue, 31 Dec 2024, "Vodapalli, Ravi Kumar" wrote: > On 12/13/2024 11:33 AM, Suraj Kandpal wrote: >> Usually retimers take around 30 to 40ms to exit all devices from >> sleep state. Extended wake timeout request helps to give additional >> time by reading the DPCD register through which sink requests the >> minimal amount of time required to wake the sink up and giving the >> same amount of wait requested by sink device. >> Spec: DP v2.1 Section 3.6.12.3 >> >> Signed-off-by: Suraj Kandpal >> --- >> drivers/gpu/drm/i915/display/intel_ddi.c | 2 + >> .../drm/i915/display/intel_dp_link_training.c | 46 +++++++++++++++++++ >> .../drm/i915/display/intel_dp_link_training.h | 1 + >> 3 files changed, 49 insertions(+) >> >> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/= i915/display/intel_ddi.c >> index 4f9c50996446..d092c3ba0ccf 100644 >> --- a/drivers/gpu/drm/i915/display/intel_ddi.c >> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c >> @@ -2624,6 +2624,8 @@ static void mtl_ddi_pre_enable_dp(struct intel_ato= mic_state *state, >> if (!is_mst) >> intel_dp_set_power(intel_dp, DP_SET_POWER_D0); >>=20=20=20 >> + intel_dp_lttpr_wake_timeout_setup(intel_dp); >> + >> intel_dp_configure_protocol_converter(intel_dp, crtc_state); >> if (!is_mst) >> intel_dp_sink_enable_decompression(state, >> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/dri= vers/gpu/drm/i915/display/intel_dp_link_training.c >> index ea9b4730a176..d0f0da78794e 100644 >> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c >> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c >> @@ -134,6 +134,52 @@ static bool intel_dp_lttpr_transparent_mode_enabled= (struct intel_dp *intel_dp) >> DP_PHY_REPEATER_MODE_TRANSPARENT; >> } >>=20=20=20 >> +void intel_dp_lttpr_wake_timeout_setup(struct intel_dp *intel_dp) >> +{ >> + struct intel_display *display =3D to_intel_display(intel_dp); >> + u8 val =3D 1; >> + int ret; >> + >> + if (intel_dp_lttpr_transparent_mode_enabled(intel_dp)) { >> + static const u8 timeout_mapping[] =3D { >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_1_MS] =3D 1, >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_20_MS] =3D 20, >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_40_MS] =3D 40, >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_20_MS] =3D 20, >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_80_MS] =3D 80, >> + [DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_100_MS] =3D 100, >> + }; Btw this kind of stuff totally belongs in generic DP helpers instead of our driver. >> + >> + ret =3D drm_dp_dpcd_readb(&intel_dp->aux, >> + DP_EXTENDED_DPRX_SLEEP_WAKE_TIMEOUT_REQUEST, &val); >> + if (ret !=3D 1) { >> + drm_dbg_kms(display->drm, >> + "Failed to read Extended sleep wake timeout request\n"); >> + return; > > Returning from function without return type, better to declare int in=20 > place of void and return the error=C2=A0 value. That depends on what you're going to do with that error value. We're not going to check it anyway, are we? > > int intel_dp_lttpr_wake_timeout_setup(struct intel_dp *intel_dp) > > > Regards, > Ravi Kumar V >> + } >> + >> + val =3D (val < sizeof(timeout_mapping) && timeout_mapping[val]) ? >> + timeout_mapping[val] : 1; What's the point with this? We don't do anything with val? BR, Jani. >> + >> + drm_dp_dpcd_writeb(&intel_dp->aux, DP_EXTENDED_DPRX_SLEEP_WAKE_TIMEOU= T_GRANT, >> + DP_DPRX_SLEEP_WAKE_TIMEOUT_PERIOD_GRANTED); >> + } else { >> + ret =3D drm_dp_dpcd_readb(&intel_dp->aux, >> + DP_PHY_REPEATER_EXTENDED_WAIT_TIMEOUT, &val); >> + if (ret !=3D 1) { >> + drm_dbg_kms(display->drm, >> + "Failed to read Extended sleep wake timeout request\n"); >> + return; >> + } >> + >> + val =3D (val & DP_EXTENDED_WAKE_TIMEOUT_REQUEST_MASK) ? >> + (val & DP_EXTENDED_WAKE_TIMEOUT_REQUEST_MASK) * 10 : 1; >> + >> + drm_dp_dpcd_writeb(&intel_dp->aux, DP_PHY_REPEATER_EXTENDED_WAIT_TIME= OUT, >> + DP_EXTENDED_WAKE_TIMEOUT_GRANT); >> + } >> +} >> + >> /* >> * Read the LTTPR common capabilities and switch the LTTPR PHYs to >> * non-transparent mode if this is supported. Preserve the >> diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.h b/dri= vers/gpu/drm/i915/display/intel_dp_link_training.h >> index 2066b9146762..cd4e0d6db6ed 100644 >> --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.h >> +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.h >> @@ -15,6 +15,7 @@ struct intel_dp; >>=20=20=20 >> int intel_dp_read_dprx_caps(struct intel_dp *intel_dp, u8 dpcd[DP_RECE= IVER_CAP_SIZE]); >> int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp); >> +void intel_dp_lttpr_wake_timeout_setup(struct intel_dp *intel_dp); >>=20=20=20 >> void intel_dp_link_training_set_mode(struct intel_dp *intel_dp, >> int link_rate, bool is_vrr); > --=20 Jani Nikula, Intel