From patchwork Thu Oct 24 22:31:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Clint Taylor X-Patchwork-Id: 13849815 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 1E78AD1038E for ; Thu, 24 Oct 2024 22:31:48 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AF5E110E9AA; Thu, 24 Oct 2024 22:31:47 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="IHYmWOiK"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) by gabe.freedesktop.org (Postfix) with ESMTPS id 534C010E9AA; Thu, 24 Oct 2024 22:31:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1729809095; x=1761345095; h=from:to:subject:date:message-id:in-reply-to:references: mime-version:content-transfer-encoding; bh=wir1OW34CDvY4sYHiQf10SnfJmQ3srInYnvu7N8Izh4=; b=IHYmWOiK2zhFKd6gGUPqjRxWFivt8wgQWGyNSf7EGLrGMaJOzo6ym7lM 7gOfNiUCe1SgdVmY5r+BSyGVDTvnVRc7oPoojbmYT8iiSZlI0CPLYHSdy ZdwMjTTdLfYRIsNLVyewCIHPX6ZpK2JRiob7p/cr5WD93RCeWXqtDRU32 YVnTAd6BbqPhgtHzXtZ+tuuCLUY+2HOzMow936Si1MHw9U2PbASU5Fvou Sk4R+vmG1xdMrUihGikbwamVFKgJJqn+rXh7MZTEzsvcetlp3EMcrtNec AA8jz4Lhc7TasSP45vHJral3677EdmkWd54GE9Mx7kCTY/01El+T3aYU1 w==; X-CSE-ConnectionGUID: AWs5ySBmQHm6JL15BFthBg== X-CSE-MsgGUID: l6CBCWDgSYWTWpfQG5yHJg== X-IronPort-AV: E=McAfee;i="6700,10204,11235"; a="46950814" X-IronPort-AV: E=Sophos;i="6.11,230,1725346800"; d="scan'208";a="46950814" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2024 15:31:20 -0700 X-CSE-ConnectionGUID: oLK0BH45S6qIprkuFlegIg== X-CSE-MsgGUID: 0SZjqF6LQzm8VNg2f9jLzw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.11,230,1725346800"; d="scan'208";a="80838680" Received: from cataylo2-desk.jf.intel.com ([10.165.21.140]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Oct 2024 15:31:20 -0700 From: Clint Taylor To: intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org Subject: [PATCH v4 11/11] drm/i915/xe3lpd: Power request asserting/deasserting Date: Thu, 24 Oct 2024 15:31:14 -0700 Message-Id: <20241024223114.785209-12-clinton.a.taylor@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20241024223114.785209-1-clinton.a.taylor@intel.com> References: <20241024223114.785209-1-clinton.a.taylor@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" From: Mika Kahola 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. Signed-off-by: Mika Kahola Signed-off-by: Matt Atwood Signed-off-by: Clint Taylor --- drivers/gpu/drm/i915/display/intel_tc.c | 40 +++++++++++++++++++++++++ drivers/gpu/drm/i915/i915_reg.h | 7 +++++ 2 files changed, 47 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_tc.c b/drivers/gpu/drm/i915/display/intel_tc.c index 6f2ee7dbc43b..7d9f87db381c 100644 --- a/drivers/gpu/drm/i915/display/intel_tc.c +++ b/drivers/gpu/drm/i915/display/intel_tc.c @@ -1013,6 +1013,39 @@ xelpdp_tc_phy_wait_for_tcss_power(struct intel_tc_port *tc, bool enabled) return true; } +static bool xelpdp_tc_phy_wait_for_tcss_ready(struct drm_i915_private *i915, + bool enable) +{ + if (DISPLAY_VER(i915) < 30) + return true; + + /* check if mailbox is running busy */ + if (intel_de_wait_for_clear(i915, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) { + drm_dbg_kms(&i915->drm, + "timeout waiting for TCSS mailbox run/busy bit to clear\n"); + return false; + } + + if (enable) + intel_de_write(i915, TCSS_DISP_MAILBOX_IN_DATA, 1); + else + intel_de_write(i915, TCSS_DISP_MAILBOX_IN_DATA, 0); + + intel_de_write(i915, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_DATA(1)); + + /* wait to clear mailbox running busy bit before continuing */ + if (intel_de_wait_for_clear(i915, TCSS_DISP_MAILBOX_IN_CMD, + TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) { + drm_dbg_kms(&i915->drm, + "timeout waiting for TCSS mailbox run/busy bit to clear\n"); + return false; + } + + return true; +} + 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 +1055,13 @@ static void __xelpdp_tc_phy_enable_tcss_power(struct intel_tc_port *tc, bool ena assert_tc_cold_blocked(tc); + /* + * Gfx driver workaround for PTL tcss_rxdetect_clkswb_req/ack handshake + * violation when pwwreq= 0->1 during TC7/10 entry + */ + drm_WARN_ON(&i915->drm, + !xelpdp_tc_phy_wait_for_tcss_ready(i915, enable)); + val = intel_de_read(i915, reg); if (enable) val |= XELPDP_TCSS_POWER_REQUEST; diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 8d758947f301..452325c7f427 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -4539,6 +4539,13 @@ enum skl_power_gate { #define TCSS_DDI_STATUS_HPD_LIVE_STATUS_TBT REG_BIT(1) #define TCSS_DDI_STATUS_HPD_LIVE_STATUS_ALT 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(x) TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY | \ + REG_FIELD_PREP(TCSS_DISP_MAILBOX_IN_CMD_CMD_MASK, (x)) +#define TCSS_DISP_MAILBOX_IN_DATA _MMIO(0x161304) + #define PRIMARY_SPI_TRIGGER _MMIO(0x102040) #define PRIMARY_SPI_ADDRESS _MMIO(0x102080) #define PRIMARY_SPI_REGIONID _MMIO(0x102084)