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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 BD2D8D116EA for ; Fri, 28 Nov 2025 06:41:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=IP/+a1mlgumlQQ3vm1/jgo32Lb1mNEMjURvL4qaPUnU=; b=kQglfCJ22wCe2T JeSyzE6WinFkkS55Geh16/kSFfM/kMyGDWmG1CpLR6ChiKJr3ubgeFpqBsNYAf7Ay2+u5O7DQyibE pjOBB3Y5pMgPdST8cl/Kk/2MkFUO2tgJbhOt8Zn173aNSnpRQaO4oOqXIfe1/WlVSC0aOVUpp38dp MhcE2oHByZdQdSoKQSKlIxC4cwNAW8BEftl5pj08MVchg9Oy+5C1pK9qsZOHAQLxmreJzwoYFpNOk 0tjRtdZIKh8aOuJfIlpZrzSgiN2/PGpEFwhtvnDIad+unUEOsAOB9UuAPOqZXT+UA1qFZS/hJGWlS h0OxmnyyAo2U+ft0TijQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vOsAK-000000003aB-2SPT; Fri, 28 Nov 2025 06:41:12 +0000 Received: from mgamail.intel.com ([198.175.65.20]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vOsAG-000000003X2-1BW5 for linux-i3c@lists.infradead.org; Fri, 28 Nov 2025 06:41:11 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1764312068; x=1795848068; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=SwNZYg5sUe0Jais1pb6bqJ1FM6/amujzdiVSrCVTU8Q=; b=PH5+yyNRGg9ugLTerxowp8elWR0QNtV1UmRpRD2ZlFL2q18EICTnVzbD BnQzyuhMWICKSFMt42ag/Mv7Ry08phcK70EIMWTtcXh+l496cm9dxMmov IPgA/ayZ2peTox/XqzuFj7nD0g9qyv1PJ1d73schZSG4ZOsZh466502jJ k0LXT/5Lhoh2E/KZBpdYD5pN7flGUsekohNR82OKimpBCFz+RF4YlMfue 3pBD8QkJcD00sjezoSSmUYRQbZIzmOCPFJ72IvlQ0GAw4AFFm7Dn0DtMv hjK+UNsmAZGWYyAppYFGWc/m4OfY65hA5NR4tFMGiMOYtOyNbdkf7FpV3 Q==; X-CSE-ConnectionGUID: u/XIsufASMeAPG/8w1X2Hw== X-CSE-MsgGUID: Nok9y0wBSROBJFZaWhUe8A== X-IronPort-AV: E=McAfee;i="6800,10657,11626"; a="66059965" X-IronPort-AV: E=Sophos;i="6.20,232,1758610800"; d="scan'208";a="66059965" Received: from fmviesa004.fm.intel.com ([10.60.135.144]) by orvoesa112.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Nov 2025 22:41:08 -0800 X-CSE-ConnectionGUID: lN7UySHyRvmke3Ly7T0InA== X-CSE-MsgGUID: yD/eonO6STGoLLSk4PlroQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,232,1758610800"; d="scan'208";a="198348119" Received: from fpallare-mobl4.ger.corp.intel.com (HELO ahunter6-desk) ([10.245.244.155]) by fmviesa004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Nov 2025 22:41:06 -0800 From: Adrian Hunter To: alexandre.belloni@bootlin.com Cc: Frank.Li@nxp.com, linux-i3c@lists.infradead.org Subject: [PATCH V5 11/12] i3c: mipi-i3c-hci-pci: Add LTR support for Intel controllers Date: Fri, 28 Nov 2025 08:40:37 +0200 Message-ID: <20251128064038.55158-12-adrian.hunter@intel.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251128064038.55158-1-adrian.hunter@intel.com> References: <20251128064038.55158-1-adrian.hunter@intel.com> MIME-Version: 1.0 Organization: Intel Finland Oy, Registered Address: c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo, Business Identity Code: 0357606 - 4, Domiciled in Helsinki X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251127_224109_785357_5EA41888 X-CRM114-Status: GOOD ( 16.07 ) X-BeenThere: linux-i3c@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=archiver.kernel.org@lists.infradead.org Add support for Latency Tolerance Reporting (LTR) for Intel controllers. Implement PM ->set_latency_tolerance() callback to set LTR register values. Also expose LTR register values via debugfs. Signed-off-by: Adrian Hunter Reviewed-by: Frank Li --- Changes in V5: Add Frank's Rev'd-by Rename intel_exit to intel_i3c_exit to match intel_i3c_init Changes in V4: Drop intel_actualize_debugfs_root() that created 'intel-i3c' debugfs directory. Changes in V3: Squash previous patch into this one Changes in V2: Make use of FIELD_PREP() Improve handling of values that exceed the maximum .../master/mipi-i3c-hci/mipi-i3c-hci-pci.c | 113 +++++++++++++++++- 1 file changed, 112 insertions(+), 1 deletion(-) diff --git a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c index 7a91efbd3e54..25c129a856d6 100644 --- a/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c +++ b/drivers/i3c/master/mipi-i3c-hci/mipi-i3c-hci-pci.c @@ -7,17 +7,21 @@ * Author: Jarkko Nikula */ #include +#include +#include #include #include #include #include #include #include +#include struct mipi_i3c_hci_pci { struct pci_dev *pci; struct platform_device *pdev; const struct mipi_i3c_hci_pci_info *info; + void *private; }; struct mipi_i3c_hci_pci_info { @@ -34,6 +38,99 @@ static DEFINE_IDA(mipi_i3c_hci_pci_ida); #define INTEL_RESETS_RESET_DONE BIT(1) #define INTEL_RESETS_TIMEOUT_US (10 * USEC_PER_MSEC) +#define INTEL_ACTIVELTR 0x0c +#define INTEL_IDLELTR 0x10 + +#define INTEL_LTR_REQ BIT(15) +#define INTEL_LTR_SCALE_MASK GENMASK(11, 10) +#define INTEL_LTR_SCALE_1US FIELD_PREP(INTEL_LTR_SCALE_MASK, 2) +#define INTEL_LTR_SCALE_32US FIELD_PREP(INTEL_LTR_SCALE_MASK, 3) +#define INTEL_LTR_VALUE_MASK GENMASK(9, 0) + +struct intel_host { + void __iomem *priv; + u32 active_ltr; + u32 idle_ltr; + struct dentry *debugfs_root; +}; + +static void intel_cache_ltr(struct intel_host *host) +{ + host->active_ltr = readl(host->priv + INTEL_ACTIVELTR); + host->idle_ltr = readl(host->priv + INTEL_IDLELTR); +} + +static void intel_ltr_set(struct device *dev, s32 val) +{ + struct mipi_i3c_hci_pci *hci = dev_get_drvdata(dev); + struct intel_host *host = hci->private; + u32 ltr; + + /* + * Program latency tolerance (LTR) accordingly what has been asked + * by the PM QoS layer or disable it in case we were passed + * negative value or PM_QOS_LATENCY_ANY. + */ + ltr = readl(host->priv + INTEL_ACTIVELTR); + + if (val == PM_QOS_LATENCY_ANY || val < 0) { + ltr &= ~INTEL_LTR_REQ; + } else { + ltr |= INTEL_LTR_REQ; + ltr &= ~INTEL_LTR_SCALE_MASK; + ltr &= ~INTEL_LTR_VALUE_MASK; + + if (val > INTEL_LTR_VALUE_MASK) { + val >>= 5; + if (val > INTEL_LTR_VALUE_MASK) + val = INTEL_LTR_VALUE_MASK; + ltr |= INTEL_LTR_SCALE_32US | val; + } else { + ltr |= INTEL_LTR_SCALE_1US | val; + } + } + + if (ltr == host->active_ltr) + return; + + writel(ltr, host->priv + INTEL_ACTIVELTR); + writel(ltr, host->priv + INTEL_IDLELTR); + + /* Cache the values into intel_host structure */ + intel_cache_ltr(host); +} + +static void intel_ltr_expose(struct device *dev) +{ + dev->power.set_latency_tolerance = intel_ltr_set; + dev_pm_qos_expose_latency_tolerance(dev); +} + +static void intel_ltr_hide(struct device *dev) +{ + dev_pm_qos_hide_latency_tolerance(dev); + dev->power.set_latency_tolerance = NULL; +} + +static void intel_add_debugfs(struct mipi_i3c_hci_pci *hci) +{ + struct dentry *dir = debugfs_create_dir(dev_name(&hci->pci->dev), NULL); + struct intel_host *host = hci->private; + + intel_cache_ltr(host); + + host->debugfs_root = dir; + debugfs_create_x32("active_ltr", 0444, dir, &host->active_ltr); + debugfs_create_x32("idle_ltr", 0444, dir, &host->idle_ltr); +} + +static void intel_remove_debugfs(struct mipi_i3c_hci_pci *hci) +{ + struct intel_host *host = hci->private; + + debugfs_remove_recursive(host->debugfs_root); +} + static void intel_reset(void __iomem *priv) { u32 reg; @@ -55,20 +152,34 @@ static void __iomem *intel_priv(struct pci_dev *pci) static int intel_i3c_init(struct mipi_i3c_hci_pci *hci) { + struct intel_host *host = devm_kzalloc(&hci->pci->dev, sizeof(*host), GFP_KERNEL); void __iomem *priv = intel_priv(hci->pci); - if (!priv) + if (!host || !priv) return -ENOMEM; dma_set_mask_and_coherent(&hci->pci->dev, DMA_BIT_MASK(64)); + hci->private = host; + host->priv = priv; + intel_reset(priv); + intel_ltr_expose(&hci->pci->dev); + intel_add_debugfs(hci); + return 0; } +static void intel_i3c_exit(struct mipi_i3c_hci_pci *hci) +{ + intel_remove_debugfs(hci); + intel_ltr_hide(&hci->pci->dev); +} + static const struct mipi_i3c_hci_pci_info intel_info = { .init = intel_i3c_init, + .exit = intel_i3c_exit, }; static int mipi_i3c_hci_pci_probe(struct pci_dev *pci, -- 2.51.0 -- linux-i3c mailing list linux-i3c@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-i3c