From patchwork Tue Aug 26 15:03:34 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 4782871 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4F385C0338 for ; Tue, 26 Aug 2014 15:06:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2CA9820117 for ; Tue, 26 Aug 2014 15:06:03 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E2D0120114 for ; Tue, 26 Aug 2014 15:06:01 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XMIHq-00057d-Dq; Tue, 26 Aug 2014 15:03:54 +0000 Received: from fw-tnat.cambridge.arm.com ([217.140.96.21] helo=cam-smtp0.cambridge.arm.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XMIHl-0004oE-Ft for linux-arm-kernel@lists.infradead.org; Tue, 26 Aug 2014 15:03:50 +0000 Received: from e103737-lin.cambridge.arm.com (e103737-lin.cambridge.arm.com [10.1.207.61]) by cam-smtp0.cambridge.arm.com (8.13.8/8.13.8) with ESMTP id s7QF3H64024351; Tue, 26 Aug 2014 16:03:20 +0100 From: Sudeep Holla To: ALKML Subject: [PATCH 1/2] GICv3: refactor gic_enable_redist to support both enabling and disabling Date: Tue, 26 Aug 2014 16:03:34 +0100 Message-Id: <1409065415-20176-2-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1409065415-20176-1-git-send-email-sudeep.holla@arm.com> References: <1409065415-20176-1-git-send-email-sudeep.holla@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140826_080350_023294_CEA3FD3C X-CRM114-Status: GOOD ( 14.12 ) X-Spam-Score: -2.3 (--) Cc: Marc Zyngier , Thomas Gleixner , Lorenzo Pieralisi , Jason Cooper , Sudeep Holla X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, 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 From: Sudeep Holla Currently gic_enable_redist configures the redistributors to never assert WakeRequest signal. However when powering down the processors with wake-up enabled(i.e suspend), we need to configure it to assert that signal. This patch extends gic_enable_redist so that the redistributor can be configure to assert WakeRequest and hold interrupts as pending. This is useful in suspending the processors. This patch also adds check to make sure GICR_WAKER is accessible when configuring it. Cc: Lorenzo Pieralisi Signed-off-by: Sudeep Holla [maz: removed reference to GICD_CTLR.DS and added read-back of GICR_WAKER to check that it is not RAZ/WI] Signed-off-by: Marc Zyngier --- drivers/irqchip/irq-gic-v3.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c index 57eaa5a0b1e3..37062ba6704b 100644 --- a/drivers/irqchip/irq-gic-v3.c +++ b/drivers/irqchip/irq-gic-v3.c @@ -155,7 +155,7 @@ static void gic_enable_sre(void) pr_err("GIC: unable to set SRE (disabled at EL2), panic ahead\n"); } -static void gic_enable_redist(void) +static void gic_enable_redist(bool enable) { void __iomem *rbase; u32 count = 1000000; /* 1s! */ @@ -163,20 +163,30 @@ static void gic_enable_redist(void) rbase = gic_data_rdist_rd_base(); - /* Wake up this CPU redistributor */ val = readl_relaxed(rbase + GICR_WAKER); - val &= ~GICR_WAKER_ProcessorSleep; + if (enable) + /* Wake up this CPU redistributor */ + val &= ~GICR_WAKER_ProcessorSleep; + else + val |= GICR_WAKER_ProcessorSleep; writel_relaxed(val, rbase + GICR_WAKER); - while (readl_relaxed(rbase + GICR_WAKER) & GICR_WAKER_ChildrenAsleep) { - count--; - if (!count) { - pr_err_ratelimited("redist didn't wake up...\n"); - return; - } + if (!enable) { /* Check that GICR_WAKER is writeable */ + val = readl_relaxed(rbase + GICR_WAKER); + if (!(val & GICR_WAKER_ProcessorSleep)) + return; /* No PM support in this redistributor */ + } + + while (count--) { + val = readl_relaxed(rbase + GICR_WAKER); + if (enable ^ (val & GICR_WAKER_ChildrenAsleep)) + break; cpu_relax(); udelay(1); }; + if (!count) + pr_err_ratelimited("redistributor failed to %s...\n", + enable ? "wakeup" : "sleep"); } /* @@ -381,7 +391,7 @@ static void gic_cpu_init(void) if (gic_populate_rdist()) return; - gic_enable_redist(); + gic_enable_redist(true); rbase = gic_data_rdist_sgi_base();