From patchwork Thu Feb 29 14:14:37 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathias Nyman X-Patchwork-Id: 13577174 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4DD3412FB29 for ; Thu, 29 Feb 2024 14:13:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.21 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709216001; cv=none; b=Xld3pqxBW6mh1ZES7aje1ETekoaQMlyoK8S+ZAxeQfoIIagU2r/60JpGjs4KnYxwww9O8Wn14vpydbYIpq80QKfmIgrnRcRRh0IZn6rr4x9nhV6UxFKpnsuvfJB0scJXSAH7xYfhXT0omkf8W5aMu9bC8M/CzZfC1/bDYflWjKM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709216001; c=relaxed/simple; bh=x8njXuX7QPqpTwdtLMXaToyhbmGMPg88HNXHkBcXCHs=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=HGcpMJFWtJCHtHR+wCpcpRFML9KKAmUC6DNkf0orYbD0NpZsMt5oOreEvILYVtGgP5yHR5V/26Z24rR3lmzwGjJgbFHXEaragn8At3Eaq43cs3PODks3pRF1tqhAIBCKDK1HkABTq1s/+5bxEGzw6pSZ1NqEgYt1umkwEkSdXaU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ZyrXE8RR; arc=none smtp.client-ip=198.175.65.21 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ZyrXE8RR" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1709216000; x=1740752000; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=x8njXuX7QPqpTwdtLMXaToyhbmGMPg88HNXHkBcXCHs=; b=ZyrXE8RRhP5TRnFdYLF/rjRIkTBaU72v1Sd3LTYPcfGjPNycjwTj5e22 JidIMKKF0txPhf+BvUgGCf0TckUc+Uc6KXPcZnZlVoCIIGtSmFwLgEMNb YJumRBq4UuOxYiNLlPjFKeRZGYFvfegL7jL+YCgHCh2Ld+C129EDfqsGK PLFnha25VqTPpWFiZBqU4QG6Qnv2Ew9C27Qn8a8yJvXm1NrORwv7xJDWw F+2P7/7ac5O1iRMZN4EquZe1dJbZQzFIxrzXFYK92Ow0LL7N01+AczwBC OhTVxAkNVSCBtfkRgSTVTD58BMC7jQG3JTHPLtHNSQcRSFaCJRfqmhnku w==; X-IronPort-AV: E=McAfee;i="6600,9927,10998"; a="3609406" X-IronPort-AV: E=Sophos;i="6.06,194,1705392000"; d="scan'208";a="3609406" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Feb 2024 06:13:19 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10998"; a="937035996" X-IronPort-AV: E=Sophos;i="6.06,194,1705392000"; d="scan'208";a="937035996" Received: from mattu-haswell.fi.intel.com ([10.237.72.199]) by fmsmga001.fm.intel.com with ESMTP; 29 Feb 2024 06:13:16 -0800 From: Mathias Nyman To: Cc: linux-usb@vger.kernel.org, Mathias Nyman , Uday M Bhat Subject: [PATCH 8/9] xhci: dbc: poll at different rate depending on data transfer activity Date: Thu, 29 Feb 2024 16:14:37 +0200 Message-Id: <20240229141438.619372-9-mathias.nyman@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240229141438.619372-1-mathias.nyman@linux.intel.com> References: <20240229141438.619372-1-mathias.nyman@linux.intel.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 DbC driver starts polling for events immediately when DbC is enabled. The current polling interval is 1ms, which keeps the CPU busy, impacting power management even when there are no active data transfers. Solve this by polling at a slower rate, with a 64ms interval as default until a transfer request is queued, or if there are still are pending unhandled transfers at event completion. Tested-by: Uday M Bhat Signed-off-by: Mathias Nyman --- drivers/usb/host/xhci-dbgcap.c | 13 +++++++++++-- drivers/usb/host/xhci-dbgcap.h | 2 ++ 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c index d82935d31126..8a9869ef0db6 100644 --- a/drivers/usb/host/xhci-dbgcap.c +++ b/drivers/usb/host/xhci-dbgcap.c @@ -634,7 +634,8 @@ static int xhci_dbc_start(struct xhci_dbc *dbc) return ret; } - return mod_delayed_work(system_wq, &dbc->event_work, 1); + return mod_delayed_work(system_wq, &dbc->event_work, + msecs_to_jiffies(dbc->poll_interval)); } static void xhci_dbc_stop(struct xhci_dbc *dbc) @@ -899,8 +900,10 @@ static void xhci_dbc_handle_events(struct work_struct *work) enum evtreturn evtr; struct xhci_dbc *dbc; unsigned long flags; + unsigned int poll_interval; dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work); + poll_interval = dbc->poll_interval; spin_lock_irqsave(&dbc->lock, flags); evtr = xhci_dbc_do_handle_events(dbc); @@ -916,13 +919,18 @@ static void xhci_dbc_handle_events(struct work_struct *work) dbc->driver->disconnect(dbc); break; case EVT_DONE: + /* set fast poll rate if there are pending data transfers */ + if (!list_empty(&dbc->eps[BULK_OUT].list_pending) || + !list_empty(&dbc->eps[BULK_IN].list_pending)) + poll_interval = 1; break; default: dev_info(dbc->dev, "stop handling dbc events\n"); return; } - mod_delayed_work(system_wq, &dbc->event_work, 1); + mod_delayed_work(system_wq, &dbc->event_work, + msecs_to_jiffies(poll_interval)); } static const char * const dbc_state_strings[DS_MAX] = { @@ -1175,6 +1183,7 @@ xhci_alloc_dbc(struct device *dev, void __iomem *base, const struct dbc_driver * dbc->idVendor = DBC_VENDOR_ID; dbc->bcdDevice = DBC_DEVICE_REV; dbc->bInterfaceProtocol = DBC_PROTOCOL; + dbc->poll_interval = DBC_POLL_INTERVAL_DEFAULT; if (readl(&dbc->regs->control) & DBC_CTRL_DBC_ENABLE) goto err; diff --git a/drivers/usb/host/xhci-dbgcap.h b/drivers/usb/host/xhci-dbgcap.h index e39e3ae1677a..92661b555c2a 100644 --- a/drivers/usb/host/xhci-dbgcap.h +++ b/drivers/usb/host/xhci-dbgcap.h @@ -94,6 +94,7 @@ struct dbc_ep { #define DBC_QUEUE_SIZE 16 #define DBC_WRITE_BUF_SIZE 8192 +#define DBC_POLL_INTERVAL_DEFAULT 64 /* milliseconds */ /* * Private structure for DbC hardware state: @@ -140,6 +141,7 @@ struct xhci_dbc { enum dbc_state state; struct delayed_work event_work; + unsigned int poll_interval; /* ms */ unsigned resume_required:1; struct dbc_ep eps[2];