From patchwork Tue May 5 15:13:41 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suman Tripathi X-Patchwork-Id: 6340501 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 2AEC9BEEE1 for ; Tue, 5 May 2015 17:33:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 426E820259 for ; Tue, 5 May 2015 17:32:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 359B520166 for ; Tue, 5 May 2015 17:32:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759123AbbEEQG4 (ORCPT ); Tue, 5 May 2015 12:06:56 -0400 Received: from denmail01-v4020.amcc.com ([192.195.68.30]:40183 "EHLO denmail01.amcc.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2993336AbbEEPOd (ORCPT ); Tue, 5 May 2015 11:14:33 -0400 Received: from apm.com (pnqlwv037.amcc.com [10.48.19.137]) by denmail01.amcc.com (8.13.8/8.13.8) with ESMTP id t45FDw6w005378; Tue, 5 May 2015 09:13:59 -0600 Received: (from stripath@localhost) by apm.com (8.13.8/8.13.8/Submit) id t45FDwvb017540; Tue, 5 May 2015 20:43:58 +0530 From: Suman Tripathi To: olof@lixom.net, tj@kernel.org, arnd@arndb.de Cc: linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mlangsdo@redhat.com, jcm@redhat.com, patches@apm.com, Suman Tripathi Subject: [PATCH v4 1/2] libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch. Date: Tue, 5 May 2015 20:43:41 +0530 Message-Id: <1430838822-17507-2-git-send-email-stripathi@apm.com> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1430838822-17507-1-git-send-email-stripathi@apm.com> References: <1430838822-17507-1-git-send-email-stripathi@apm.com> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds the support to handle HOST_IRQ_STAT as edge trigger latch. Signed-off-by: Suman Tripathi --- drivers/ata/ahci.h | 2 ++ drivers/ata/libahci.c | 93 +++++++++++++++++++++++++++++++++++++++------------ 2 files changed, 73 insertions(+), 22 deletions(-) -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h index 71262e0..2df2237 100644 --- a/drivers/ata/ahci.h +++ b/drivers/ata/ahci.h @@ -238,6 +238,8 @@ enum { AHCI_HFLAG_MULTI_MSI = (1 << 16), /* multiple PCI MSIs */ AHCI_HFLAG_NO_DEVSLP = (1 << 17), /* no device sleep */ AHCI_HFLAG_NO_FBS = (1 << 18), /* no FBS */ + AHCI_HFLAG_EDGE_TRIG_IRQ = (1 << 19), /* HOST_IRQ_STAT behaves as + Edge Triggered */ /* ap->flags bits */ diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index 61a9c07..6f1a603 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -1826,27 +1826,9 @@ static irqreturn_t ahci_multi_irqs_intr(int irq, void *dev_instance) return IRQ_WAKE_THREAD; } -static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance) +static u32 ahci_handle_port_intr(struct ata_host *host, u32 irq_masked) { - struct ata_host *host = dev_instance; - struct ahci_host_priv *hpriv; unsigned int i, handled = 0; - void __iomem *mmio; - u32 irq_stat, irq_masked; - - VPRINTK("ENTER\n"); - - hpriv = host->private_data; - mmio = hpriv->mmio; - - /* sigh. 0xffffffff is a valid return from h/w */ - irq_stat = readl(mmio + HOST_IRQ_STAT); - if (!irq_stat) - return IRQ_NONE; - - irq_masked = irq_stat & hpriv->port_map; - - spin_lock(&host->lock); for (i = 0; i < host->n_ports; i++) { struct ata_port *ap; @@ -1864,10 +1846,36 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance) dev_warn(host->dev, "interrupt on disabled port %u\n", i); } - handled = 1; } + return handled; +} + +static irqreturn_t ahci_level_trig_intr(int irq, void *dev_instance) +{ + struct ata_host *host = dev_instance; + struct ahci_host_priv *hpriv; + unsigned int rc = 0; + void __iomem *mmio; + u32 irq_stat, irq_masked; + + VPRINTK("ENTER\n"); + + hpriv = host->private_data; + mmio = hpriv->mmio; + + /* sigh. 0xffffffff is a valid return from h/w */ + irq_stat = readl(mmio + HOST_IRQ_STAT); + if (!irq_stat) + return IRQ_NONE; + + irq_masked = irq_stat & hpriv->port_map; + + spin_lock(&host->lock); + + rc = ahci_handle_port_intr(host, irq_masked); + /* HOST_IRQ_STAT behaves as level triggered latch meaning that * it should be cleared after all the port events are cleared; * otherwise, it will raise a spurious interrupt after each @@ -1877,13 +1885,51 @@ static irqreturn_t ahci_single_irq_intr(int irq, void *dev_instance) * Also, use the unmasked value to clear interrupt as spurious * pending event on a dummy port might cause screaming IRQ. */ + + writel(irq_stat, mmio + HOST_IRQ_STAT); + + spin_unlock(&host->lock); + + VPRINTK("EXIT\n"); + + return IRQ_RETVAL(rc); +} + +static irqreturn_t ahci_edge_trig_intr(int irq, void *dev_instance) +{ + struct ata_host *host = dev_instance; + struct ahci_host_priv *hpriv; + unsigned int rc = 0; + void __iomem *mmio; + u32 irq_stat, irq_masked; + + VPRINTK("ENTER\n"); + + hpriv = host->private_data; + mmio = hpriv->mmio; + + /* sigh. 0xffffffff is a valid return from h/w */ + irq_stat = readl(mmio + HOST_IRQ_STAT); + if (!irq_stat) + return IRQ_NONE; + + irq_masked = irq_stat & hpriv->port_map; + + spin_lock(&host->lock); + + /* + * HOST_IRQ_STAT behaves as edge triggered latch meaning that + * it should be cleared before all the port events are cleared; + */ writel(irq_stat, mmio + HOST_IRQ_STAT); + rc = ahci_handle_port_intr(host, irq_masked); + spin_unlock(&host->lock); VPRINTK("EXIT\n"); - return IRQ_RETVAL(handled); + return IRQ_RETVAL(rc); } unsigned int ahci_qc_issue(struct ata_queued_cmd *qc) @@ -2486,8 +2532,11 @@ int ahci_host_activate(struct ata_host *host, int irq, if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) rc = ahci_host_activate_multi_irqs(host, irq, sht); + else if (hpriv->flags & AHCI_HFLAG_EDGE_TRIG_IRQ) + rc = ata_host_activate(host, irq, ahci_edge_trig_intr, + IRQF_SHARED, sht); else - rc = ata_host_activate(host, irq, ahci_single_irq_intr, + rc = ata_host_activate(host, irq, ahci_level_trig_intr, IRQF_SHARED, sht); return rc; }