From patchwork Tue Mar 8 14:24:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Whitchurch X-Patchwork-Id: 12773896 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C6530C4332F for ; Tue, 8 Mar 2022 14:24:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347095AbiCHOZX (ORCPT ); Tue, 8 Mar 2022 09:25:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51214 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230433AbiCHOZV (ORCPT ); Tue, 8 Mar 2022 09:25:21 -0500 Received: from smtp2.axis.com (smtp2.axis.com [195.60.68.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 690CC4B859; Tue, 8 Mar 2022 06:24:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; q=dns/txt; s=axis-central1; t=1646749463; x=1678285463; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=rFioSpH+5uUKbkMGJw1iA2/404Dx7lV4IUNdiyH/vxw=; b=JMpGYNo9FAtHlhNQqdUWImuQ8GADoh/QigC1WxRr82ppGbKGzv02i2en Vuvz3SOelwX4x/seJSxoPDxseaassK7HLel1PCsD7WF2NLM8Oa+TDEqGG NwUvSmdd43ZUbmOnv+ZKRVN1URhz5Hl5xC1FpK7CFOB2jrr+TbxLYkM1f SnB4sm7M36fI9lf2vRzaSBgdCLRxAgd0NVwH4y4/yPJdK4E61xxJzBAyV NfTQte/S9+hDL9rSSarMw0JZ2GV7IVr68dlKvB0siOebz02raAyEPqRAC 6FwUA1+/2doAaQz/b8QvixdnhSVme7rNudk64qsZ99uev7YE1MYYqt/lM Q==; From: Vincent Whitchurch To: , , CC: , , , , , , , Vincent Whitchurch Subject: [PATCH v2 3/4] clocksource/drivers/exynos_mct: Support local-timer-index property Date: Tue, 8 Mar 2022 15:24:09 +0100 Message-ID: <20220308142410.3193729-4-vincent.whitchurch@axis.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220308142410.3193729-1-vincent.whitchurch@axis.com> References: <20220308142410.3193729-1-vincent.whitchurch@axis.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org Support the documented semantics of the local-timer-index property: Use it as the first index of the local timer, ensure that global timer clock events device is not registered, and don't write to the global FRC if it is already started. Signed-off-by: Vincent Whitchurch --- Notes: v2: Use devicetree property instead of module parameter. drivers/clocksource/exynos_mct.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c index f29c812b70c9..5f8b516614eb 100644 --- a/drivers/clocksource/exynos_mct.c +++ b/drivers/clocksource/exynos_mct.c @@ -33,7 +33,7 @@ #define EXYNOS4_MCT_G_INT_ENB EXYNOS4_MCTREG(0x248) #define EXYNOS4_MCT_G_WSTAT EXYNOS4_MCTREG(0x24C) #define _EXYNOS4_MCT_L_BASE EXYNOS4_MCTREG(0x300) -#define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * x)) +#define EXYNOS4_MCT_L_BASE(x) (_EXYNOS4_MCT_L_BASE + (0x100 * (x))) #define EXYNOS4_MCT_L_MASK (0xffffff00) #define MCT_L_TCNTB_OFFSET (0x00) @@ -75,6 +75,7 @@ enum { static void __iomem *reg_base; static unsigned long clk_rate; static unsigned int mct_int_type; +static unsigned int mct_local_idx; static int mct_irqs[MCT_NR_IRQS]; struct mct_clock_event_device { @@ -157,6 +158,17 @@ static void exynos4_mct_frc_start(void) u32 reg; reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON); + + /* + * If the FRC is already running, we don't need to start it again. We + * could probably just do this on all systems, but, to avoid any risk + * for regressions, we only do it on systems where it's absolutely + * necessary (i.e., on systems where writes to the global registers + * need to be avoided). + */ + if (mct_local_idx && (reg & MCT_G_TCON_START)) + return; + reg |= MCT_G_TCON_START; exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON); } @@ -449,7 +461,7 @@ static int exynos4_mct_starting_cpu(unsigned int cpu) per_cpu_ptr(&percpu_mct_tick, cpu); struct clock_event_device *evt = &mevt->evt; - mevt->base = EXYNOS4_MCT_L_BASE(cpu); + mevt->base = EXYNOS4_MCT_L_BASE(mct_local_idx + cpu); snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu); evt->name = mevt->name; @@ -554,13 +566,14 @@ static int __init exynos4_timer_interrupts(struct device_node *np, } else { for_each_possible_cpu(cpu) { int mct_irq; + unsigned int irqidx = MCT_L0_IRQ + mct_local_idx + cpu; struct mct_clock_event_device *pcpu_mevt = per_cpu_ptr(&percpu_mct_tick, cpu); pcpu_mevt->evt.irq = -1; - if (MCT_L0_IRQ + cpu >= ARRAY_SIZE(mct_irqs)) + if (irqidx >= ARRAY_SIZE(mct_irqs)) break; - mct_irq = mct_irqs[MCT_L0_IRQ + cpu]; + mct_irq = mct_irqs[irqidx]; irq_set_status_flags(mct_irq, IRQ_NOAUTOEN); if (request_irq(mct_irq, @@ -607,6 +620,8 @@ static int __init mct_init_dt(struct device_node *np, unsigned int int_type) { int ret; + of_property_read_u32(np, "local-timer-index", &mct_local_idx); + ret = exynos4_timer_resources(np); if (ret) return ret; @@ -619,7 +634,7 @@ static int __init mct_init_dt(struct device_node *np, unsigned int int_type) if (ret) return ret; - return exynos4_clockevent_init(); + return (mct_local_idx == 0) ? exynos4_clockevent_init() : ret; }