From patchwork Sat Oct 8 06:37:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yinbo Zhu X-Patchwork-Id: 613558 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 AA6A1C4332F for ; Sat, 8 Oct 2022 06:37:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229543AbiJHGhh (ORCPT ); Sat, 8 Oct 2022 02:37:37 -0400 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 S229463AbiJHGhf (ORCPT ); Sat, 8 Oct 2022 02:37:35 -0400 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 53E548680B; Fri, 7 Oct 2022 23:37:33 -0700 (PDT) Received: from localhost.localdomain (unknown [10.180.13.64]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxqmqeGkFjxEEoAA--.12544S2; Sat, 08 Oct 2022 14:37:24 +0800 (CST) From: Yinbo Zhu To: Daniel Lezcano , Thomas Gleixner , Rob Herring , Krzysztof Kozlowski , Huacai Chen , WANG Xuerui , Jiaxun Yang , Jianmin Lv , Yun Liu , Yang Li , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, loongarch@lists.linux.dev, Yinbo Zhu Subject: [PATCH v2 1/2] clocksource: loongson2_hpet: add hpet driver support Date: Sat, 8 Oct 2022 14:37:09 +0800 Message-Id: <20221008063710.12241-1-zhuyinbo@loongson.cn> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-CM-TRANSID: AQAAf8CxqmqeGkFjxEEoAA--.12544S2 X-Coremail-Antispam: 1UD129KBjvJXoW3ZF1kGry7tF1xKr4rWryUKFg_yoWkXFWrpr Wxua43JFW5XrnrZws5tF1DCF98Zw48ur9rG343t3yjyw18JryrXF40qa42vF12krWxZwsF ga98Kay8CFyqyaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvl14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26r xl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj 6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_Jr 0_Gr1lF7xvr2IYc2Ij64vIr41lF7I21c0EjII2zVCS5cI20VAGYxC7M4IIrI8v6xkF7I0E 8cxan2IY04v7MxkIecxEwVCm-wCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJV W8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF 1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6x IIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvE x4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvj DU0xZFpf9x0JUdHUDUUUUU= X-CM-SenderInfo: 52kx5xhqerqz5rrqw2lrqou0/ Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org HPET (High Precision Event Timer) defines a new set of timers, which are used by the operating system to schedule threads, interrupt the kernel and interrupt the multimedia timer server. The operating system can assign different timers to different applications. By configuration, each timer can generate interrupt independently. The loongson2 HPET module includes a main count and three comparators , all of which are 32 bits wide. Among the three comparators, only one comparator supports periodic interrupt, all three comparators support non periodic interrupts. Signed-off-by: Yinbo Zhu --- MAINTAINERS | 6 + arch/loongarch/kernel/time.c | 3 + drivers/clocksource/Kconfig | 9 + drivers/clocksource/Makefile | 1 + drivers/clocksource/loongson2_hpet.c | 332 +++++++++++++++++++++++++++ 5 files changed, 351 insertions(+) create mode 100644 drivers/clocksource/loongson2_hpet.c diff --git a/MAINTAINERS b/MAINTAINERS index 0be0f520c032..c2e8eac61642 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11907,6 +11907,12 @@ S: Maintained F: Documentation/devicetree/bindings/thermal/loongson,ls2k-thermal.yaml F: drivers/thermal/loongson2_thermal.c +LOONGSON2 SOC SERIES HPET DRIVER +M: Yinbo Zhu +L: linux-kernel@vger.kernel.org +S: Maintained +F: drivers/clocksource/loongson2_hpet.c + LSILOGIC MPT FUSION DRIVERS (FC/SAS/SPI) M: Sathya Prakash M: Sreekanth Reddy diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c index 786735dcc8d6..74f34c74679a 100644 --- a/arch/loongarch/kernel/time.c +++ b/arch/loongarch/kernel/time.c @@ -214,6 +214,9 @@ int __init constant_clocksource_init(void) void __init time_init(void) { +#ifdef CONFIG_TIMER_PROBE + timer_probe(); +#endif if (!cpu_has_cpucfg) const_clock_freq = cpu_clock_freq; else diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 4f2bb7315b67..1c7ab3541d81 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -721,4 +721,13 @@ config GOLDFISH_TIMER help Support for the timer/counter of goldfish-rtc +config LOONGSON2_HPET + bool "Loongson2 High Precision Event Timer (HPET)" + select TIMER_PROBE + select TIMER_OF + help + This option enables Loongson2 High Precision Event Timer + (HPET) module driver. It supports the oneshot, the periodic + modes and high resolution. It is used as a clocksource and + a clockevent. endmenu diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 64ab547de97b..1a3abb770f11 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -88,3 +88,4 @@ obj-$(CONFIG_MICROCHIP_PIT64B) += timer-microchip-pit64b.o obj-$(CONFIG_MSC313E_TIMER) += timer-msc313e.o obj-$(CONFIG_GOLDFISH_TIMER) += timer-goldfish.o obj-$(CONFIG_GXP_TIMER) += timer-gxp.o +obj-$(CONFIG_LOONGSON2_HPET) += loongson2_hpet.o diff --git a/drivers/clocksource/loongson2_hpet.c b/drivers/clocksource/loongson2_hpet.c new file mode 100644 index 000000000000..5525edd255eb --- /dev/null +++ b/drivers/clocksource/loongson2_hpet.c @@ -0,0 +1,332 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Author: Yinbo Zhu + * Copyright (C) 2022-2023 Loongson Technology Corporation Limited + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +/* HPET regs */ +#define HPET_CFG 0x010 +#define HPET_STATUS 0x020 +#define HPET_COUNTER 0x0f0 +#define HPET_T0_IRS 0x001 +#define HPET_T0_CFG 0x100 +#define HPET_T0_CMP 0x108 +#define HPET_CFG_ENABLE 0x001 +#define HPET_TN_LEVEL 0x0002 +#define HPET_TN_ENABLE 0x0004 +#define HPET_TN_PERIODIC 0x0008 +#define HPET_TN_SETVAL 0x0040 +#define HPET_TN_32BIT 0x0100 + +#define HPET_MIN_CYCLES 16 +#define HPET_MIN_PROG_DELTA (HPET_MIN_CYCLES * 12) +#define HPET_COMPARE_VAL ((hpet_freq + HZ / 2) / HZ) + +void __iomem *hpet_mmio_base; +unsigned int hpet_freq; +unsigned int hpet_t0_irq; +unsigned int hpet_irq_flags; +unsigned int hpet_t0_cfg; + +static DEFINE_SPINLOCK(hpet_lock); +DEFINE_PER_CPU(struct clock_event_device, hpet_clockevent_device); + +static int hpet_read(int offset) +{ + return readl(hpet_mmio_base + offset); +} + +static void hpet_write(int offset, int data) +{ + writel(data, hpet_mmio_base + offset); +} + +static void hpet_start_counter(void) +{ + unsigned int cfg = hpet_read(HPET_CFG); + + cfg |= HPET_CFG_ENABLE; + hpet_write(HPET_CFG, cfg); +} + +static void hpet_stop_counter(void) +{ + unsigned int cfg = hpet_read(HPET_CFG); + + cfg &= ~HPET_CFG_ENABLE; + hpet_write(HPET_CFG, cfg); +} + +static void hpet_reset_counter(void) +{ + hpet_write(HPET_COUNTER, 0); + hpet_write(HPET_COUNTER + 4, 0); +} + +static void hpet_restart_counter(void) +{ + hpet_stop_counter(); + hpet_reset_counter(); + hpet_start_counter(); +} + +static void hpet_enable_legacy_int(void) +{ + /* Do nothing on Loongson2 */ +} + +static int hpet_set_state_periodic(struct clock_event_device *evt) +{ + int cfg; + + spin_lock(&hpet_lock); + + pr_info("set clock event to periodic mode!\n"); + /* stop counter */ + hpet_stop_counter(); + hpet_reset_counter(); + hpet_write(HPET_T0_CMP, 0); + + /* enables the timer0 to generate a periodic interrupt */ + cfg = hpet_read(HPET_T0_CFG); + cfg &= ~HPET_TN_LEVEL; + cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC | HPET_TN_SETVAL | + HPET_TN_32BIT | hpet_irq_flags; + hpet_write(HPET_T0_CFG, cfg); + + /* set the comparator */ + hpet_write(HPET_T0_CMP, HPET_COMPARE_VAL); + udelay(1); + hpet_write(HPET_T0_CMP, HPET_COMPARE_VAL); + + /* start counter */ + hpet_start_counter(); + + spin_unlock(&hpet_lock); + return 0; +} + +static int hpet_set_state_shutdown(struct clock_event_device *evt) +{ + int cfg; + + spin_lock(&hpet_lock); + + cfg = hpet_read(HPET_T0_CFG); + cfg &= ~HPET_TN_ENABLE; + hpet_write(HPET_T0_CFG, cfg); + + spin_unlock(&hpet_lock); + return 0; +} + +static int hpet_set_state_oneshot(struct clock_event_device *evt) +{ + int cfg; + + spin_lock(&hpet_lock); + + pr_info("set clock event to one shot mode!\n"); + cfg = hpet_read(HPET_T0_CFG); + /* + * set timer0 type + * 1 : periodic interrupt + * 0 : non-periodic(oneshot) interrupt + */ + cfg &= ~HPET_TN_PERIODIC; + cfg |= HPET_TN_ENABLE | HPET_TN_32BIT | + hpet_irq_flags; + hpet_write(HPET_T0_CFG, cfg); + + /* start counter */ + hpet_start_counter(); + + spin_unlock(&hpet_lock); + return 0; +} + +static int hpet_tick_resume(struct clock_event_device *evt) +{ + spin_lock(&hpet_lock); + hpet_enable_legacy_int(); + spin_unlock(&hpet_lock); + + return 0; +} + +static int hpet_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + u32 cnt; + s32 res; + + cnt = hpet_read(HPET_COUNTER); + cnt += (u32) delta; + hpet_write(HPET_T0_CMP, cnt); + + res = (s32)(cnt - hpet_read(HPET_COUNTER)); + + return res < HPET_MIN_CYCLES ? -ETIME : 0; +} + +static irqreturn_t hpet_irq_handler(int irq, void *data) +{ + int is_irq; + struct clock_event_device *cd; + unsigned int cpu = smp_processor_id(); + + is_irq = hpet_read(HPET_STATUS); + if (is_irq & HPET_T0_IRS) { + /* clear the TIMER0 irq status register */ + hpet_write(HPET_STATUS, HPET_T0_IRS); + cd = &per_cpu(hpet_clockevent_device, cpu); + cd->event_handler(cd); + return IRQ_HANDLED; + } + return IRQ_NONE; +} + +static struct irqaction hpet_irq_str = { + .handler = hpet_irq_handler, + .flags = IRQD_NO_BALANCING | IRQF_TIMER, + .name = "hpet", +}; + +/* + * HPET address assignation and irq setting should be done in bios. + * But, sometimes bios don't do this, we just setup here directly. + */ +static void hpet_setup(void) +{ + hpet_enable_legacy_int(); +} + +static int hpet_setup_irq(struct clock_event_device *cd) +{ + setup_irq(cd->irq, &hpet_irq_str); + + disable_irq(cd->irq); + irq_set_affinity(cd->irq, cd->cpumask); + enable_irq(cd->irq); + + return 0; +} + +static int __init loongson2_hpet_clockevent_init(void) +{ + unsigned int cpu = smp_processor_id(); + struct clock_event_device *cd; + + hpet_setup(); + + cd = &per_cpu(hpet_clockevent_device, cpu); + cd->name = "hpet"; + cd->rating = 300; + cd->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; + cd->set_state_shutdown = hpet_set_state_shutdown; + cd->set_state_periodic = hpet_set_state_periodic; + cd->set_state_oneshot = hpet_set_state_oneshot; + cd->tick_resume = hpet_tick_resume; + cd->set_next_event = hpet_next_event; + cd->irq = hpet_t0_irq; + cd->cpumask = cpumask_of(cpu); + clockevent_set_clock(cd, hpet_freq); + cd->max_delta_ns = clockevent_delta2ns(0x7fffffff, cd); + cd->max_delta_ticks = 0x7fffffff; + cd->min_delta_ns = clockevent_delta2ns(HPET_MIN_PROG_DELTA, cd); + cd->min_delta_ticks = HPET_MIN_PROG_DELTA; + + clockevents_register_device(cd); + hpet_setup_irq(cd); + + pr_info("hpet clock event device register\n"); + + return 0; +} + +static u64 hpet_read_counter(struct clocksource *cs) +{ + return (u64)hpet_read(HPET_COUNTER); +} + +static void hpet_suspend(struct clocksource *cs) +{ + hpet_t0_cfg = hpet_read(HPET_T0_CFG); +} + +static void hpet_resume(struct clocksource *cs) +{ + hpet_write(HPET_T0_CFG, hpet_t0_cfg); + hpet_setup(); + hpet_restart_counter(); +} + +struct clocksource csrc_hpet = { + .name = "hpet", + .rating = 300, + .read = hpet_read_counter, + .mask = CLOCKSOURCE_MASK(32), + /* oneshot mode work normal with this flag */ + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .suspend = hpet_suspend, + .resume = hpet_resume, + .mult = 0, + .shift = 10, +}; + +static int __init loongson2_hpet_clocksource_init(void) +{ + csrc_hpet.mult = clocksource_hz2mult(hpet_freq, csrc_hpet.shift); + + /* start counter */ + hpet_start_counter(); + + return clocksource_register_hz(&csrc_hpet, hpet_freq); +} + +static int __init loongson2_hpet_init(struct device_node *np) +{ + u32 clk; + int ret; + + hpet_mmio_base = of_iomap(np, 0); + if (!hpet_mmio_base) { + pr_err("hpet: unable to map loongson2 hpet registers\n"); + goto err; + } + + ret = -EINVAL; + hpet_t0_irq = irq_of_parse_and_map(np, 0); + if (hpet_t0_irq <= 0) { + pr_err("hpet: unable to get IRQ from DT, %d\n", hpet_t0_irq); + goto err; + } + + if (!of_property_read_u32(np, "clock-frequency", &clk)) + hpet_freq = clk; + else + goto err; + + hpet_irq_flags = HPET_TN_LEVEL; + + loongson2_hpet_clocksource_init(); + + loongson2_hpet_clockevent_init(); + + return 0; + +err: + iounmap(hpet_mmio_base); + return ret; +} + +TIMER_OF_DECLARE(loongson2_hpet, "loongson,ls2k-hpet", loongson2_hpet_init);