From patchwork Thu Oct 31 11:40:26 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kahola, Mika" X-Patchwork-Id: 13857830 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 9FE0EE68955 for ; Thu, 31 Oct 2024 11:49:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2A9CC10E863; Thu, 31 Oct 2024 11:49:13 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Wgm87yyh"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9C4D210E863 for ; Thu, 31 Oct 2024 11:49:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1730375350; x=1761911350; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Ah5VQ7iw+7o5vqfDxCvP35nyGa+YkOldX358bcFRdwA=; b=Wgm87yyhM4amZheyEmG1Qt/yYvNOCyU3sVQeDITDEZCqnnGDEKSsm50y 4CwS00hUCLTVm5Wb7gbXgVucunyX4Hv8FhP0iiAz1xSUCcHbdA+PYnltU AhF0K03V0ZgWkQk+N96wt9WFFeNzrFxUhod/4l2174gxydCpKeB8C8ufG j2RbP3aFfXuVBJH3Ud2XuwBW0AkNzjh/UxfOitJhzws5+0Ge7kRDYQSjf ygPgRUbwWY1/eqoTUX9efHQJeaVWaU+DZzpi8WWXXI42ENkID4S4Q9Wl3 +jD9bD7wsRGK7Tw7uM931PGUQbW8Y0t5eC4mhG2JMSQcDOsvT5AGxhgHY A==; X-CSE-ConnectionGUID: mMwOFwlyQ2W57u3mHwok8A== X-CSE-MsgGUID: BygPsU83Q+yw0G6e+c1Sjg== X-IronPort-AV: E=McAfee;i="6700,10204,11222"; a="40654016" X-IronPort-AV: E=Sophos;i="6.11,199,1725346800"; d="scan'208";a="40654016" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 31 Oct 2024 04:49:10 -0700 X-CSE-ConnectionGUID: Ao25vi2uQwyydt406ndytw== X-CSE-MsgGUID: eeaHzg3cQIqd8BR8hpdbjQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,247,1725346800"; d="scan'208";a="113451925" Received: from sorvi2.fi.intel.com ([10.237.72.194]) by fmviesa001.fm.intel.com with ESMTP; 31 Oct 2024 04:49:09 -0700 From: Mika Kahola To: intel-gfx@lists.freedesktop.org Cc: raag.jadav@intel.com, gustavo.sousa@intel.com, jani.nikula@linux.intel.com, Mika Kahola Subject: [PATCH v3 1/2] drm/i915/xe3lpd: Power request asserting/deasserting Date: Thu, 31 Oct 2024 13:40:26 +0200 Message-ID: <20241031114027.225217-2-mika.kahola@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241031114027.225217-1-mika.kahola@intel.com> References: <20241031114027.225217-1-mika.kahola@intel.com> MIME-Version: 1.0 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" There is a HW issue that arises when there are race conditions between TCSS entering/exiting TC7 or TC10 states while the driver is asserting/deasserting TCSS power request. As a workaround, Display driver will implement a mailbox sequence to ensure that the TCSS is in TC0 when TCSS power request is asserted/deasserted. The sequence is the following 1. Read mailbox command status and wait until run/busy bit is clear 2. Write mailbox data value '1' for power request asserting and '0' for power request deasserting 3. Write mailbox command run/busy bit and command value with 0x1 4. Read mailbox command and wait until run/busy bit is clear before continuing power request. v2: Rename WA function (Gustavo) Limit WA only for PTL platform with a TODO note (Gustavo) Add TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY for clarity when writing register data (Gustavo) Move register defs from i915_reg.h to intel_cx0_phy_regs.h (Gustavo) v3: use "struct intel_display" instead of "struct drm_i915_private" (Jani) Move defs above C10 definitions in the intel_cx0_phy_regs.h file (Gustavo) Move drm_WARN_ON() inside WA function (Gustavo) Rename workaround function as wa_14020908590() (Gustvo) Use boolean enable instead of if-else structure (Raag) Signed-off-by: Mika Kahola Reviewed-by: Raag Jadav --- .../gpu/drm/i915/display/intel_cx0_phy_regs.h | 8 +++++ drivers/gpu/drm/i915/display/intel_tc.c | 32 +++++++++++++++++++ 2 files changed, 40 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h b/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h index f0e5c196eae4..5a0b55cca4a3 100644 --- a/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h +++ b/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h @@ -200,6 +200,14 @@ #define XELPDP_SSC_ENABLE_PLLA REG_BIT(1) #define XELPDP_SSC_ENABLE_PLLB REG_BIT(0) +#define TCSS_DISP_MAILBOX_IN_CMD _MMIO(0x161300) +#define TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY REG_BIT(31) +#define TCSS_DISP_MAILBOX_IN_CMD_CMD_MASK REG_GENMASK(7, 0) +#define TCSS_DISP_MAILBOX_IN_CMD_DATA(val) (TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY | \ + REG_FIELD_PREP(TCSS_DISP_MAILBOX_IN_CMD_CMD_MASK, val)) + +#define TCSS_DISP_MAILBOX_IN_DATA _MMIO(0x161304) + /* C10 Vendor Registers */ #define PHY_C10_VDR_PLL(idx) (0xC00 + (idx)) #define C10_PLL0_FRACEN REG_BIT8(4) diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c index b16c4d2d4077..dab2ac7ec0dd 100644 --- a/drivers/gpu/drm/i915/display/intel_tc.c +++ b/drivers/gpu/drm/i915/display/intel_tc.c @@ -1013,6 +1013,31 @@ xelpdp_tc_phy_wait_for_tcss_power(struct intel_tc_port *tc, bool enabled) return true; } +static void wa_14020908590(struct intel_display *display, + bool enable) +{ + /* check if mailbox is running busy */ + if (intel_de_wait_for_clear(display, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) { + drm_dbg_kms(display->drm, + "Timeout waiting for TCSS mailbox run/busy bit to clear\n"); + return; + } + + intel_de_write(display, TCSS_DISP_MAILBOX_IN_DATA, enable); + intel_de_write(display, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY | + TCSS_DISP_MAILBOX_IN_CMD_DATA(0x1)); + + /* wait to clear mailbox running busy bit before continuing */ + if (intel_de_wait_for_clear(display, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) { + drm_dbg_kms(display->drm, + "Timeout after writing data to mailbox. Mailbox run/busy bit did not clear\n"); + return; + } +} + static void __xelpdp_tc_phy_enable_tcss_power(struct intel_tc_port *tc, bool enable) { struct drm_i915_private *i915 = tc_to_i915(tc); @@ -1022,6 +1047,13 @@ static void __xelpdp_tc_phy_enable_tcss_power(struct intel_tc_port *tc, bool ena assert_tc_cold_blocked(tc); + /* + * Gfx driver WA 14020908590 for PTL tcss_rxdetect_clkswb_req/ack + * handshake violation when pwwreq= 0->1 during TC7/10 entry + */ + if (DISPLAY_VER(i915) == 30) + wa_14020908590(&i915->display, enable); + val = intel_de_read(i915, reg); if (enable) val |= XELPDP_TCSS_POWER_REQUEST;