From patchwork Tue Oct 6 17:02:05 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Felipe Balbi X-Patchwork-Id: 7337711 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 0D8249F1D5 for ; Tue, 6 Oct 2015 17:03:12 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id E23DF2076B for ; Tue, 6 Oct 2015 17:03:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C819220776 for ; Tue, 6 Oct 2015 17:03:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752970AbbJFRC5 (ORCPT ); Tue, 6 Oct 2015 13:02:57 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:35939 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752950AbbJFRCz (ORCPT ); Tue, 6 Oct 2015 13:02:55 -0400 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id t96H2L0F001429; Tue, 6 Oct 2015 12:02:21 -0500 Received: from DFLE72.ent.ti.com (dfle72.ent.ti.com [128.247.5.109]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id t96H2Lgk002834; Tue, 6 Oct 2015 12:02:21 -0500 Received: from dflp32.itg.ti.com (10.64.6.15) by DFLE72.ent.ti.com (128.247.5.109) with Microsoft SMTP Server id 14.3.224.2; Tue, 6 Oct 2015 12:02:22 -0500 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp32.itg.ti.com (8.14.3/8.13.8) with ESMTP id t96H2KR9018217; Tue, 6 Oct 2015 12:02:21 -0500 From: Felipe Balbi To: Tony Lindgren CC: Linux OMAP Mailing List , Linux ARM Kernel Mailing List , , , Linux Kernel Mailing List , Felipe Balbi Subject: [PATCH 09/11] clocksource: add TI 32.768 Hz counter driver Date: Tue, 6 Oct 2015 12:02:05 -0500 Message-ID: <1444150927-14771-10-git-send-email-balbi@ti.com> X-Mailer: git-send-email 2.5.3 In-Reply-To: <1444150927-14771-1-git-send-email-balbi@ti.com> References: <1444150927-14771-1-git-send-email-balbi@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@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 Introduce a new clocksource driver for Texas Instruments 32.768 Hz device which is available on most OMAP-like devices. Signed-off-by: Felipe Balbi Acked-by: Daniel Lezcano --- drivers/clocksource/Kconfig | 7 +++ drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-ti-32k.c | 122 +++++++++++++++++++++++++++++++++++++ 3 files changed, 130 insertions(+) create mode 100644 drivers/clocksource/timer-ti-32k.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index a7726db13abb..98b2a9b9bfad 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -115,6 +115,13 @@ config CLKSRC_PISTACHIO bool select CLKSRC_OF +config CLKSRC_TI_32K + bool "Texas Instruments 32.768 Hz Clocksource" if COMPILE_TEST + select CLKSRC_OF if OF + help + This option enables support for Texas Instruments 32.768 Hz clocksource + available on many OMAP-like platforms. + config CLKSRC_STM32 bool "Clocksource for STM32 SoCs" if !ARCH_STM32 depends on OF && ARM && (ARCH_STM32 || COMPILE_TEST) diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 5c00863c3e33..749abc3665b3 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -45,6 +45,7 @@ obj-$(CONFIG_VF_PIT_TIMER) += vf_pit_timer.o obj-$(CONFIG_CLKSRC_QCOM) += qcom-timer.o obj-$(CONFIG_MTK_TIMER) += mtk_timer.o obj-$(CONFIG_CLKSRC_PISTACHIO) += time-pistachio.o +obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o diff --git a/drivers/clocksource/timer-ti-32k.c b/drivers/clocksource/timer-ti-32k.c new file mode 100644 index 000000000000..12e2ca7bcc49 --- /dev/null +++ b/drivers/clocksource/timer-ti-32k.c @@ -0,0 +1,122 @@ +/** + * timer-ti-32k.c - OMAP2 32k Timer Support + * + * Copyright (C) 2009 Nokia Corporation + * + * Update to use new clocksource/clockevent layers + * Author: Kevin Hilman, MontaVista Software, Inc. + * Copyright (C) 2007 MontaVista Software, Inc. + * + * Original driver: + * Copyright (C) 2005 Nokia Corporation + * Author: Paul Mundt + * Juha Yrjölä + * OMAP Dual-mode timer framework support by Timo Teras + * + * Some parts based off of TI's 24xx code: + * + * Copyright (C) 2004-2009 Texas Instruments, Inc. + * + * Roughly modelled after the OMAP1 MPU timer code. + * Added OMAP4 support - Santosh Shilimkar + * + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 of + * the License as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include +#include + +/* + * 32KHz clocksource ... always available, on pretty most chips except + * OMAP 730 and 1510. Other timers could be used as clocksources, with + * higher resolution in free-running counter modes (e.g. 12 MHz xtal), + * but systems won't necessarily want to spend resources that way. + */ + +#define OMAP2_32KSYNCNT_REV_OFF 0x0 +#define OMAP2_32KSYNCNT_REV_SCHEME (0x3 << 30) +#define OMAP2_32KSYNCNT_CR_OFF_LOW 0x10 +#define OMAP2_32KSYNCNT_CR_OFF_HIGH 0x30 + +struct ti_32k { + void __iomem *base; + void __iomem *counter; + struct clocksource cs; +}; +#define to_ti_32k(cs) (container_of((cs), struct ti_32k, cs)) + +static cycle_t ti_32k_read_cycles(struct clocksource *cs) +{ + struct ti_32k *ti = to_ti_32k(cs); + + return (cycle_t)readl_relaxed(ti->counter); +} + +static struct ti_32k ti_32k_timer = { + .cs = { + .name = "32k_counter", + .rating = 250, + .read = ti_32k_read_cycles, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS | + CLOCK_SOURCE_SUSPEND_NONSTOP, + }, +}; + +static u64 notrace omap_32k_read_sched_clock(void) +{ + return ti_32k_read_cycles(&ti_32k_timer.cs); +} + +static void __init ti_32k_timer_init(struct device_node *np) +{ + int ret; + + ti_32k_timer.base = of_iomap(np, 0); + if (!ti_32k_timer.base) { + pr_err("Can't ioremap 32k timer base\n"); + return; + } + + ti_32k_timer.counter = ti_32k_timer.base; + + /* + * 32k sync Counter IP register offsets vary between the highlander + * version and the legacy ones. + * + * The 'SCHEME' bits(30-31) of the revision register is used to identify + * the version. + */ + if (readl_relaxed(ti_32k_timer.base + OMAP2_32KSYNCNT_REV_OFF) & + OMAP2_32KSYNCNT_REV_SCHEME) + ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_HIGH; + else + ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_LOW; + + ret = clocksource_register_hz(&ti_32k_timer.cs, 32768); + if (ret) { + pr_err("32k_counter: can't register clocksource\n"); + return; + } + + sched_clock_register(omap_32k_read_sched_clock, 32, 32768); + pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n"); +} +CLOCKSOURCE_OF_DECLARE(ti_32k_timer, "ti,omap-counter32k", + ti_32k_timer_init);