Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752228AbcC2Mwa (ORCPT ); Tue, 29 Mar 2016 08:52:30 -0400 Received: from us01smtprelay-2.synopsys.com ([198.182.60.111]:41172 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751146AbcC2Mw2 (ORCPT ); Tue, 29 Mar 2016 08:52:28 -0400 Subject: Re: [PATCH v6 2/3] clocksource: Add NPS400 timers driver To: Noam Camus , , , References: <1458570272-23037-1-git-send-email-noamca@mellanox.com> <1458570272-23037-3-git-send-email-noamca@mellanox.com> CC: , Rob Herring , "John Stultz" , Noam Camus , "Thomas Gleixner" , Newsgroups: gmane.linux.kernel.arc,gmane.linux.kernel From: Vineet Gupta Message-ID: <56FA7A77.6080901@synopsys.com> Date: Tue, 29 Mar 2016 18:22:07 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1458570272-23037-3-git-send-email-noamca@mellanox.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.12.197.157] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6868 Lines: 192 On Monday 21 March 2016 07:54 PM, Noam Camus wrote: > From: Noam Camus > > Add internal tick generator which is shared by all cores. > Each cluster of cores view it through dedicated address. > This is used for SMP system where all CPUs synced by same > clock source. > > Signed-off-by: Noam Camus > Cc: Daniel Lezcano > Cc: Rob Herring > Cc: Thomas Gleixner > Cc: John Stultz > Acked-by: Vineet Gupta @Noam, AFAIKR, Daniel did ack the prev version - can you please double check and repost this again. @Daniel, this patch depends on a include/soc header introduced by patch 1/3 of the series. For 4.7, how should we merge it - take both via ARC tree ! Thx, -Vineet > --- > .../bindings/timer/ezchip,nps400-timer.txt | 15 +++ > drivers/clocksource/Kconfig | 10 ++ > drivers/clocksource/Makefile | 1 + > drivers/clocksource/timer-nps.c | 98 ++++++++++++++++++++ > 4 files changed, 124 insertions(+), 0 deletions(-) > create mode 100644 Documentation/devicetree/bindings/timer/ezchip,nps400-timer.txt > create mode 100644 drivers/clocksource/timer-nps.c > > diff --git a/Documentation/devicetree/bindings/timer/ezchip,nps400-timer.txt b/Documentation/devicetree/bindings/timer/ezchip,nps400-timer.txt > new file mode 100644 > index 0000000..c8c03d7 > --- /dev/null > +++ b/Documentation/devicetree/bindings/timer/ezchip,nps400-timer.txt > @@ -0,0 +1,15 @@ > +NPS Network Processor > + > +Required properties: > + > +- compatible : should be "ezchip,nps400-timer" > + > +Clocks required for compatible = "ezchip,nps400-timer": > +- clocks : Must contain a single entry describing the clock input > + > +Example: > + > +timer { > + compatible = "ezchip,nps400-timer"; > + clocks = <&sysclk>; > +}; > diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig > index 2eb5f0e..fa7be50 100644 > --- a/drivers/clocksource/Kconfig > +++ b/drivers/clocksource/Kconfig > @@ -132,6 +132,16 @@ config CLKSRC_TI_32K > This option enables support for Texas Instruments 32.768 Hz clocksource > available on many OMAP-like platforms. > > +config CLKSRC_NPS > + bool "NPS400 clocksource driver" if COMPILE_TEST > + depends on !PHYS_ADDR_T_64BIT > + select CLKSRC_MMIO > + select CLKSRC_OF if OF > + help > + NPS400 clocksource support. > + Got 64 bit counter with update rate up to 1000MHz. > + This counter is accessed via couple of 32 bit memory mapped registers. > + > 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 56bd16e..056cffd 100644 > --- a/drivers/clocksource/Makefile > +++ b/drivers/clocksource/Makefile > @@ -46,6 +46,7 @@ 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-$(CONFIG_CLKSRC_NPS) += timer-nps.o > > obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o > obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o > diff --git a/drivers/clocksource/timer-nps.c b/drivers/clocksource/timer-nps.c > new file mode 100644 > index 0000000..d461089 > --- /dev/null > +++ b/drivers/clocksource/timer-nps.c > @@ -0,0 +1,98 @@ > +/* > + * Copyright (c) 2016, Mellanox Technologies. All rights reserved. > + * > + * This software is available to you under a choice of one of two > + * licenses. You may choose to be licensed under the terms of the GNU > + * General Public License (GPL) Version 2, available from the file > + * COPYING in the main directory of this source tree, or the > + * OpenIB.org BSD license below: > + * > + * Redistribution and use in source and binary forms, with or > + * without modification, are permitted provided that the following > + * conditions are met: > + * > + * - Redistributions of source code must retain the above > + * copyright notice, this list of conditions and the following > + * disclaimer. > + * > + * - Redistributions in binary form must reproduce the above > + * copyright notice, this list of conditions and the following > + * disclaimer in the documentation and/or other materials > + * provided with the distribution. > + * > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, > + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF > + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND > + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS > + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN > + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN > + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE > + * SOFTWARE. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define NPS_MSU_TICK_LOW 0xC8 > +#define NPS_CLUSTER_OFFSET 8 > +#define NPS_CLUSTER_NUM 16 > + > +/* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */ > +static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly; > + > +static unsigned long nps_timer_rate; > + > +static cycle_t nps_clksrc_read(struct clocksource *clksrc) > +{ > + int cluster = raw_smp_processor_id() >> NPS_CLUSTER_OFFSET; > + > + return (cycle_t)ioread32be(nps_msu_reg_low_addr[cluster]); > +} > + > +static void __init nps_setup_clocksource(struct device_node *node, > + struct clk *clk) > +{ > + int ret, cluster; > + > + for (cluster = 0; cluster < NPS_CLUSTER_NUM; cluster++) > + nps_msu_reg_low_addr[cluster] = > + nps_host_reg((cluster << NPS_CLUSTER_OFFSET), > + NPS_MSU_BLKID, NPS_MSU_TICK_LOW); > + > + ret = clk_prepare_enable(clk); > + if (ret) { > + pr_err("Couldn't enable parent clock\n"); > + return; > + } > + > + nps_timer_rate = clk_get_rate(clk); > + > + ret = clocksource_mmio_init(nps_msu_reg_low_addr, "EZnps-tick", > + nps_timer_rate, 301, 32, nps_clksrc_read); > + if (ret) { > + pr_err("Couldn't register clock source.\n"); > + clk_disable_unprepare(clk); > + } > +} > + > +static void __init nps_timer_init(struct device_node *node) > +{ > + struct clk *clk; > + > + clk = of_clk_get(node, 0); > + if (IS_ERR(clk)) { > + pr_err("Can't get timer clock.\n"); > + return; > + } > + > + nps_setup_clocksource(node, clk); > +} > + > +CLOCKSOURCE_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer", > + nps_timer_init); >