From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0308C04E87 for ; Fri, 28 Sep 2018 00:52:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90C482173D for ; Fri, 28 Sep 2018 00:52:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90C482173D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-sky.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728906AbeI1HN6 (ORCPT ); Fri, 28 Sep 2018 03:13:58 -0400 Received: from smtp2200-217.mail.aliyun.com ([121.197.200.217]:33899 "EHLO smtp2200-217.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728744AbeI1HN4 (ORCPT ); Fri, 28 Sep 2018 03:13:56 -0400 X-Alimail-AntiSpam: AC=CONTINUE;BC=0.07437667|-1;CH=blue;FP=12654327938056916218|1|1|12|0|-1|-1|-1;HT=e02c03297;MF=ren_guo@c-sky.com;NM=1;PH=DS;RN=18;RT=18;SR=0;TI=SMTPD_---.Cwkfe-z_1538095937; Received: from localhost(mailfrom:ren_guo@c-sky.com fp:SMTPD_---.Cwkfe-z_1538095937) by smtp.aliyun-inc.com(10.147.41.231); Fri, 28 Sep 2018 08:52:18 +0800 From: Guo Ren To: akpm@linux-foundation.org, arnd@arndb.de, daniel.lezcano@linaro.org, davem@davemloft.net, gregkh@linuxfoundation.org, jason@lakedaemon.net, marc.zyngier@arm.com, mark.rutland@arm.com, mchehab+samsung@kernel.org, peterz@infradead.org, robh@kernel.org, robh+dt@kernel.org, tglx@linutronix.de Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, devicetree@vger.kernel.org, green.hu@gmail.com, Guo Ren Subject: [PATCH V6 24/33] clocksource: add C-SKY SMP timer Date: Fri, 28 Sep 2018 08:51:21 +0800 Message-Id: <8d77e9b1f4e71f84e7f7795adfaa74adfaf4ab01.1538058840.git.ren_guo@c-sky.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <62098e7d0a7fbdd09f44d7e23333dad258a01bd2.1538058840.git.ren_guo@c-sky.com> References: <62098e7d0a7fbdd09f44d7e23333dad258a01bd2.1538058840.git.ren_guo@c-sky.com> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This timer is used by SMP system and use mfcr/mtcr instruction to access the regs. Changelog: - Remove #define CPUHP_AP_CSKY_TIMER_STARTING - Add CPUHP_AP_CSKY_TIMER_STARTING in cpuhotplug.h - Support csky mp timer alpha version. - Just use low-counter with 32bit width as clocksource. - Coding convention with upstream feed-back. Signed-off-by: Guo Ren --- drivers/clocksource/Kconfig | 8 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/csky_mptimer.c | 176 +++++++++++++++++++++++++++++++++++++ include/linux/cpuhotplug.h | 1 + 4 files changed, 186 insertions(+) create mode 100644 drivers/clocksource/csky_mptimer.c diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index a11f4ba..a28043f 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -620,4 +620,12 @@ config RISCV_TIMER is accessed via both the SBI and the rdcycle instruction. This is required for all RISC-V systems. +config CSKY_MPTIMER + bool "C-SKY Multi Processor Timer" + depends on CSKY + select TIMER_OF + help + Say yes here to enable C-SKY SMP timer driver used for C-SKY SMP + system. + endmenu diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index db51b24..848c676 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -79,3 +79,4 @@ obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o obj-$(CONFIG_RISCV_TIMER) += riscv_timer.o +obj-$(CONFIG_CSKY_MPTIMER) += csky_mptimer.o diff --git a/drivers/clocksource/csky_mptimer.c b/drivers/clocksource/csky_mptimer.c new file mode 100644 index 0000000..9dc3cfb --- /dev/null +++ b/drivers/clocksource/csky_mptimer.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include +#include +#include +#include +#include + +#include "timer-of.h" + +#define PTIM_CCVR "cr<3, 14>" +#define PTIM_CTLR "cr<0, 14>" +#define PTIM_LVR "cr<6, 14>" +#define PTIM_TSR "cr<1, 14>" + +static int csky_mptimer_set_next_event(unsigned long delta, struct clock_event_device *ce) +{ + mtcr(PTIM_LVR, delta); + + return 0; +} + +static int csky_mptimer_shutdown(struct clock_event_device *ce) +{ + mtcr(PTIM_CTLR, 0); + + return 0; +} + +static int csky_mptimer_oneshot(struct clock_event_device *ce) +{ + mtcr(PTIM_CTLR, 1); + + return 0; +} + +static int csky_mptimer_oneshot_stopped(struct clock_event_device *ce) +{ + mtcr(PTIM_CTLR, 0); + + return 0; +} + +static DEFINE_PER_CPU(struct timer_of, csky_to) = { + .flags = TIMER_OF_CLOCK, + .clkevt = { + .rating = 300, + .features = CLOCK_EVT_FEAT_PERCPU | + CLOCK_EVT_FEAT_ONESHOT, + .set_state_shutdown = csky_mptimer_shutdown, + .set_state_oneshot = csky_mptimer_oneshot, + .set_state_oneshot_stopped = csky_mptimer_oneshot_stopped, + .set_next_event = csky_mptimer_set_next_event, + }, + .of_irq = { + .flags = IRQF_TIMER, + .percpu = 1, + }, +}; + +static irqreturn_t timer_interrupt(int irq, void *dev) +{ + struct timer_of *to = this_cpu_ptr(&csky_to); + + mtcr(PTIM_TSR, 0); + + to->clkevt.event_handler(&to->clkevt); + + return IRQ_HANDLED; +} + +/* + * clock event for percpu + */ +static int csky_mptimer_starting_cpu(unsigned int cpu) +{ + struct timer_of *to = per_cpu_ptr(&csky_to, cpu); + + to->clkevt.cpumask = cpumask_of(cpu); + + clockevents_config_and_register(&to->clkevt, timer_of_rate(to), 2, ULONG_MAX); + + enable_percpu_irq(timer_of_irq(to), 0); + + return 0; +} + +static int csky_mptimer_dying_cpu(unsigned int cpu) +{ + struct timer_of *to = per_cpu_ptr(&csky_to, cpu); + + disable_percpu_irq(timer_of_irq(to)); + + return 0; +} + +/* + * clock source + */ +static u64 sched_clock_read(void) +{ + return (u64) mfcr(PTIM_CCVR); +} + +static u64 clksrc_read(struct clocksource *c) +{ + return (u64) mfcr(PTIM_CCVR); +} + +struct clocksource csky_clocksource = { + .name = "csky", + .rating = 400, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .read = clksrc_read, +}; + +static int __init csky_mptimer_init(struct device_node *np) +{ + int ret, cpu; + struct timer_of *to; + int rate = 0; + int irq = 0; + + /* + * Csky_mptimer is designed for C-SKY SMP multi-processors and + * every core has it's own private irq and regs for clkevt and + * clksrc. + * + * The regs is accessed by cpu instruction: mfcr/mtcr instead of + * mmio map style. So we needn't mmio-address in dts, but we still + * need to give clk and irq number. + * + * We use private irq for the mptimer and irq number is the same + * for every core. So we use request_percpu_irq() in timer_of_init. + */ + + for_each_possible_cpu(cpu) { + to = per_cpu_ptr(&csky_to, cpu); + + if (cpu == 0) { + to->flags |= TIMER_OF_IRQ; + to->of_irq.handler = timer_interrupt; + + ret = timer_of_init(np, to); + if (ret) + return ret; + + rate = timer_of_rate(to); + irq = to->of_irq.irq; + } else { + ret = timer_of_init(np, to); + if (ret) + return ret; + + to->of_clk.rate = rate; + to->of_irq.irq = irq; + } + } + + ret = cpuhp_setup_state(CPUHP_AP_CSKY_TIMER_STARTING, + "clockevents/csky/timer:starting", + csky_mptimer_starting_cpu, + csky_mptimer_dying_cpu); + if (ret) { + pr_err("%s: Failed to cpuhp_setup_state.\n", __func__); + return ret; + } + + clocksource_register_hz(&csky_clocksource, rate); + sched_clock_register(sched_clock_read, 32, rate); + + return 0; +} +TIMER_OF_DECLARE(csky_mptimer, "csky,mptimer", csky_mptimer_init); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index caf40ad..e0cd2ba 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -126,6 +126,7 @@ enum cpuhp_state { CPUHP_AP_MIPS_GIC_TIMER_STARTING, CPUHP_AP_ARC_TIMER_STARTING, CPUHP_AP_RISCV_TIMER_STARTING, + CPUHP_AP_CSKY_TIMER_STARTING, CPUHP_AP_KVM_STARTING, CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING, CPUHP_AP_KVM_ARM_VGIC_STARTING, -- 2.7.4