diff options
36 files changed, 666 insertions, 811 deletions
diff --git a/Documentation/devicetree/bindings/timer/renesas,tmu.txt b/Documentation/devicetree/bindings/timer/renesas,tmu.txt deleted file mode 100644 index 29159f4e65ab..000000000000 --- a/Documentation/devicetree/bindings/timer/renesas,tmu.txt +++ /dev/null @@ -1,49 +0,0 @@ -* Renesas R-Mobile/R-Car Timer Unit (TMU) - -The TMU is a 32-bit timer/counter with configurable clock inputs and -programmable compare match. - -Channels share hardware resources but their counter and compare match value -are independent. The TMU hardware supports up to three channels. - -Required Properties: - - - compatible: must contain one or more of the following: - - "renesas,tmu-r8a7740" for the r8a7740 TMU - - "renesas,tmu-r8a774a1" for the r8a774A1 TMU - - "renesas,tmu-r8a774b1" for the r8a774B1 TMU - - "renesas,tmu-r8a774c0" for the r8a774C0 TMU - - "renesas,tmu-r8a7778" for the r8a7778 TMU - - "renesas,tmu-r8a7779" for the r8a7779 TMU - - "renesas,tmu-r8a77970" for the r8a77970 TMU - - "renesas,tmu-r8a77980" for the r8a77980 TMU - - "renesas,tmu" for any TMU. - This is a fallback for the above renesas,tmu-* entries - - - reg: base address and length of the registers block for the timer module. - - - interrupts: interrupt-specifier for the timer, one per channel. - - - clocks: a list of phandle + clock-specifier pairs, one for each entry - in clock-names. - - clock-names: must contain "fck" for the functional clock. - -Optional Properties: - - - #renesas,channels: number of channels implemented by the timer, must be 2 - or 3 (if not specified the value defaults to 3). - - -Example: R8A7779 (R-Car H1) TMU0 node - - tmu0: timer@ffd80000 { - compatible = "renesas,tmu-r8a7779", "renesas,tmu"; - reg = <0xffd80000 0x30>; - interrupts = <0 32 IRQ_TYPE_LEVEL_HIGH>, - <0 33 IRQ_TYPE_LEVEL_HIGH>, - <0 34 IRQ_TYPE_LEVEL_HIGH>; - clocks = <&mstp0_clks R8A7779_CLK_TMU0>; - clock-names = "fck"; - - #renesas,channels = <3>; - }; diff --git a/Documentation/devicetree/bindings/timer/renesas,tmu.yaml b/Documentation/devicetree/bindings/timer/renesas,tmu.yaml new file mode 100644 index 000000000000..c54188731a1b --- /dev/null +++ b/Documentation/devicetree/bindings/timer/renesas,tmu.yaml @@ -0,0 +1,99 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/timer/renesas,tmu.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Renesas R-Mobile/R-Car Timer Unit (TMU) + +maintainers: + - Geert Uytterhoeven <geert+renesas@glider.be> + - Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> + +description: + The TMU is a 32-bit timer/counter with configurable clock inputs and + programmable compare match. + + Channels share hardware resources but their counter and compare match value + are independent. The TMU hardware supports up to three channels. + +properties: + compatible: + items: + - enum: + - renesas,tmu-r8a7740 # R-Mobile A1 + - renesas,tmu-r8a774a1 # RZ/G2M + - renesas,tmu-r8a774b1 # RZ/G2N + - renesas,tmu-r8a774c0 # RZ/G2E + - renesas,tmu-r8a774e1 # RZ/G2H + - renesas,tmu-r8a7778 # R-Car M1A + - renesas,tmu-r8a7779 # R-Car H1 + - renesas,tmu-r8a77970 # R-Car V3M + - renesas,tmu-r8a77980 # R-Car V3H + - const: renesas,tmu + + reg: + maxItems: 1 + + interrupts: + minItems: 2 + maxItems: 3 + + clocks: + maxItems: 1 + + clock-names: + const: fck + + power-domains: + maxItems: 1 + + resets: + maxItems: 1 + + '#renesas,channels': + description: + Number of channels implemented by the timer. + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [ 2, 3 ] + default: 3 + +required: + - compatible + - reg + - interrupts + - clocks + - clock-names + - power-domains + +if: + not: + properties: + compatible: + contains: + enum: + - renesas,tmu-r8a7740 + - renesas,tmu-r8a7778 + - renesas,tmu-r8a7779 +then: + required: + - resets + +additionalProperties: false + +examples: + - | + #include <dt-bindings/clock/r8a7779-clock.h> + #include <dt-bindings/interrupt-controller/arm-gic.h> + #include <dt-bindings/power/r8a7779-sysc.h> + tmu0: timer@ffd80000 { + compatible = "renesas,tmu-r8a7779", "renesas,tmu"; + reg = <0xffd80000 0x30>; + interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 33 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&mstp0_clks R8A7779_CLK_TMU0>; + clock-names = "fck"; + power-domains = <&sysc R8A7779_PD_ALWAYS_ON>; + #renesas,channels = <3>; + }; diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 68b087bff59c..9f00b8385fd4 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -275,16 +275,6 @@ 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 TIMER_OF if OF - help - NPS400 clocksource support. - It has a 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) @@ -654,7 +644,7 @@ config ATCPIT100_TIMER config RISCV_TIMER bool "Timer for the RISC-V platform" if COMPILE_TEST - depends on GENERIC_SCHED_CLOCK && RISCV + depends on GENERIC_SCHED_CLOCK && RISCV && RISCV_SBI select TIMER_PROBE select TIMER_OF help diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 1c444cc3bb44..3c75cbbf8533 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -56,7 +56,6 @@ obj-$(CONFIG_CLKSRC_QCOM) += timer-qcom.o obj-$(CONFIG_MTK_TIMER) += timer-mediatek.o obj-$(CONFIG_CLKSRC_PISTACHIO) += timer-pistachio.o obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o -obj-$(CONFIG_CLKSRC_NPS) += timer-nps.o obj-$(CONFIG_OXNAS_RPS_TIMER) += timer-oxnas-rps.o obj-$(CONFIG_OWL_TIMER) += timer-owl.o obj-$(CONFIG_MILBEAUT_TIMER) += timer-milbeaut.o diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 6c3e84180146..d0177824c518 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -396,10 +396,10 @@ static void erratum_set_next_event_tval_generic(const int access, unsigned long ctrl &= ~ARCH_TIMER_CTRL_IT_MASK; if (access == ARCH_TIMER_PHYS_ACCESS) { - cval = evt + arch_counter_get_cntpct(); + cval = evt + arch_counter_get_cntpct_stable(); write_sysreg(cval, cntp_cval_el0); } else { - cval = evt + arch_counter_get_cntvct(); + cval = evt + arch_counter_get_cntvct_stable(); write_sysreg(cval, cntv_cval_el0); } @@ -822,15 +822,24 @@ static void arch_timer_evtstrm_enable(int divider) static void arch_timer_configure_evtstream(void) { - int evt_stream_div, pos; + int evt_stream_div, lsb; + + /* + * As the event stream can at most be generated at half the frequency + * of the counter, use half the frequency when computing the divider. + */ + evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ / 2; + + /* + * Find the closest power of two to the divisor. If the adjacent bit + * of lsb (last set bit, starts from 0) is set, then we use (lsb + 1). + */ + lsb = fls(evt_stream_div) - 1; + if (lsb > 0 && (evt_stream_div & BIT(lsb - 1))) + lsb++; - /* Find the closest power of two to the divisor */ - evt_stream_div = arch_timer_rate / ARCH_TIMER_EVT_STREAM_FREQ; - pos = fls(evt_stream_div); - if (pos > 1 && !(evt_stream_div & (1 << (pos - 2)))) - pos--; /* enable event stream */ - arch_timer_evtstrm_enable(min(pos, 15)); + arch_timer_evtstrm_enable(max(0, min(lsb, 15))); } static void arch_counter_set_user_access(void) diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c index ab3ddebe8344..42e7e43b8fcd 100644 --- a/drivers/clocksource/dw_apb_timer_of.c +++ b/drivers/clocksource/dw_apb_timer_of.c @@ -14,12 +14,13 @@ #include <linux/reset.h> #include <linux/sched_clock.h> -static void __init timer_get_base_and_rate(struct device_node *np, +static int __init timer_get_base_and_rate(struct device_node *np, void __iomem **base, u32 *rate) { struct clk *timer_clk; struct clk *pclk; struct reset_control *rstc; + int ret; *base = of_iomap(np, 0); @@ -46,55 +47,67 @@ static void __init timer_get_base_and_rate(struct device_node *np, pr_warn("pclk for %pOFn is present, but could not be activated\n", np); + if (!of_property_read_u32(np, "clock-freq", rate) && + !of_property_read_u32(np, "clock-frequency", rate)) + return 0; + timer_clk = of_clk_get_by_name(np, "timer"); if (IS_ERR(timer_clk)) - goto try_clock_freq; + return PTR_ERR(timer_clk); - if (!clk_prepare_enable(timer_clk)) { - *rate = clk_get_rate(timer_clk); - return; - } + ret = clk_prepare_enable(timer_clk); + if (ret) + return ret; + + *rate = clk_get_rate(timer_clk); + if (!(*rate)) + return -EINVAL; -try_clock_freq: - if (of_property_read_u32(np, "clock-freq", rate) && - of_property_read_u32(np, "clock-frequency", rate)) - panic("No clock nor clock-frequency property for %pOFn", np); + return 0; } -static void __init add_clockevent(struct device_node *event_timer) +static int __init add_clockevent(struct device_node *event_timer) { void __iomem *iobase; struct dw_apb_clock_event_device *ced; u32 irq, rate; + int ret = 0; irq = irq_of_parse_and_map(event_timer, 0); if (irq == 0) panic("No IRQ for clock event timer"); - timer_get_base_and_rate(event_timer, &iobase, &rate); + ret = timer_get_base_and_rate(event_timer, &iobase, &rate); + if (ret) + return ret; ced = dw_apb_clockevent_init(-1, event_timer->name, 300, iobase, irq, rate); if (!ced) - panic("Unable to initialise clockevent device"); + return -EINVAL; dw_apb_clockevent_register(ced); + + return 0; } static void __iomem *sched_io_base; static u32 sched_rate; -static void __init add_clocksource(struct device_node *source_timer) +static int __init add_clocksource(struct device_node *source_timer) { void __iomem *iobase; struct dw_apb_clocksource *cs; u32 rate; + int ret; - timer_get_base_and_rate(source_timer, &iobase, &rate); + ret = timer_get_base_and_rate(source_timer, &iobase, &rate); + if (ret) + return ret; cs = dw_apb_clocksource_init(300, source_timer->name, iobase, rate); if (!cs) - panic("Unable to initialise clocksource device"); + return -EINVAL; dw_apb_clocksource_start(cs); dw_apb_clocksource_register(cs); @@ -106,6 +119,8 @@ static void __init add_clocksource(struct device_node *source_timer) */ sched_io_base = iobase + 0x04; sched_rate = rate; + + return 0; } static u64 notrace read_sched_clock(void) @@ -146,10 +161,14 @@ static struct delay_timer dw_apb_delay_timer = { static int num_called; static int __init dw_apb_timer_init(struct device_node *timer) { + int ret = 0; + switch (num_called) { case 1: pr_debug("%s: found clocksource timer\n", __func__); - add_clocksource(timer); + ret = add_clocksource(timer); + if (ret) + return ret; init_sched_clock(); #ifdef CONFIG_ARM dw_apb_delay_timer.freq = sched_rate; @@ -158,7 +177,9 @@ static int __init dw_apb_timer_init(struct device_node *timer) break; default: pr_debug("%s: found clockevent timer\n", __func__); - add_clockevent(timer); + ret = add_clockevent(timer); + if (ret) + return ret; break; } diff --git a/drivers/clocksource/ingenic-timer.c b/drivers/clocksource/ingenic-timer.c index 58fd9189fab7..905fd6b163a8 100644 --- a/drivers/clocksource/ingenic-timer.c +++ b/drivers/clocksource/ingenic-timer.c @@ -127,7 +127,7 @@ static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id) return IRQ_HANDLED; } -static struct clk * __init ingenic_tcu_get_clock(struct device_node *np, int id) +static struct clk *ingenic_tcu_get_clock(struct device_node *np, int id) { struct of_phandle_args args; diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c index 760777458a90..19fa3ef75e3b 100644 --- a/drivers/clocksource/sh_cmt.c +++ b/drivers/clocksource/sh_cmt.c @@ -319,7 +319,6 @@ static int sh_cmt_enable(struct sh_cmt_channel *ch) { int k, ret; - pm_runtime_get_sync(&ch->cmt->pdev->dev); dev_pm_syscore_device(&ch->cmt->pdev->dev, true); /* enable clock */ @@ -394,7 +393,6 @@ static void sh_cmt_disable(struct sh_cmt_channel *ch) clk_disable(ch->cmt->clk); dev_pm_syscore_device(&ch->cmt->pdev->dev, false); - pm_runtime_put(&ch->cmt->pdev->dev); } /* private flags */ @@ -562,10 +560,16 @@ static int sh_cmt_start(struct sh_cmt_channel *ch, unsigned long flag) int ret = 0; unsigned long flags; + if (flag & FLAG_CLOCKSOURCE) + pm_runtime_get_sync(&ch->cmt->pdev->dev); + raw_spin_lock_irqsave(&ch->lock, flags); - if (!(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) + if (!(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) { + if (flag & FLAG_CLOCKEVENT) + pm_runtime_get_sync(&ch->cmt->pdev->dev); ret = sh_cmt_enable(ch); + } if (ret) goto out; @@ -590,14 +594,20 @@ static void sh_cmt_stop(struct sh_cmt_channel *ch, unsigned long flag) f = ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE); ch->flags &= ~flag; - if (f && !(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) + if (f && !(ch->flags & (FLAG_CLOCKEVENT | FLAG_CLOCKSOURCE))) { sh_cmt_disable(ch); + if (flag & FLAG_CLOCKEVENT) + pm_runtime_put(&ch->cmt->pdev->dev); + } /* adjust the timeout to maximum if only clocksource left */ if ((flag == FLAG_CLOCKEVENT) && (ch->flags & FLAG_CLOCKSOURCE)) __sh_cmt_set_next(ch, ch->max_match_value); raw_spin_unlock_irqrestore(&ch->lock, flags); + + if (flag & FLAG_CLOCKSOURCE) + pm_runtime_put(&ch->cmt->pdev->dev); } static struct sh_cmt_channel *cs_to_sh_cmt(struct clocksource *cs) diff --git a/drivers/clocksource/timer-cadence-ttc.c b/drivers/clocksource/timer-cadence-ttc.c index 80e960602030..4efd0cf3b602 100644 --- a/drivers/clocksource/timer-cadence-ttc.c +++ b/drivers/clocksource/timer-cadence-ttc.c @@ -413,10 +413,8 @@ static int __init ttc_setup_clockevent(struct clk *clk, ttcce->ttc.clk = clk; err = clk_prepare_enable(ttcce->ttc.clk); - if (err) { - kfree(ttcce); - return err; - } + if (err) + goto out_kfree; ttcce->ttc.clk_rate_change_nb.notifier_call = ttc_rate_change_clockevent_cb; @@ -426,7 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk, &ttcce->ttc.clk_rate_change_nb); if (err) { pr_warn("Unable to register clock notifier.\n"); - return err; + goto out_kfree; } ttcce->ttc.freq = clk_get_rate(ttcce->ttc.clk); @@ -455,15 +453,17 @@ static int __init ttc_setup_clockevent(struct clk *clk, err = request_irq(irq, ttc_clock_event_interrupt, IRQF_TIMER, ttcce->ce.name, ttcce); - if (err) { - kfree(ttcce); - return err; - } + if (err) + goto out_kfree; clockevents_config_and_register(&ttcce->ce, ttcce->ttc.freq / PRESCALE, 1, 0xfffe); return 0; + +out_kfree: + kfree(ttcce); + return err; } static int __init ttc_timer_probe(struct platform_device *pdev) diff --git a/drivers/clocksource/timer-nps.c b/drivers/clocksource/timer-nps.c deleted file mode 100644 index 7b6bb0df96ae..000000000000 --- a/drivers/clocksource/timer-nps.c +++ /dev/null @@ -1,284 +0,0 @@ -/* - * 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 <linux/interrupt.h> -#include <linux/clocksource.h> -#include <linux/clockchips.h> -#include <linux/clk.h> -#include <linux/of.h> -#include <linux/of_irq.h> -#include <linux/cpu.h> -#include <soc/nps/common.h> - -#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 int __init nps_get_timer_clk(struct device_node *node, - unsigned long *timer_freq, - struct clk **clk) -{ - int ret; - - *clk = of_clk_get(node, 0); - ret = PTR_ERR_OR_ZERO(*clk); - if (ret) { - pr_err("timer missing clk\n"); - return ret; - } - - ret = clk_prepare_enable(*clk); - if (ret) { - pr_err("Couldn't enable parent clk\n"); - clk_put(*clk); - return ret; - } - - *timer_freq = clk_get_rate(*clk); - if (!(*timer_freq)) { - pr_err("Couldn't get clk rate\n"); - clk_disable_unprepare(*clk); - clk_put(*clk); - return -EINVAL; - } - - return 0; -} - -static u64 nps_clksrc_read(struct clocksource *clksrc) -{ - int cluster = raw_smp_processor_id() >> NPS_CLUSTER_OFFSET; - - return (u64)ioread32be(nps_msu_reg_low_addr[cluster]); -} - -static int __init nps_setup_clocksource(struct device_node *node) -{ - int ret, cluster; - struct clk *clk; - unsigned long nps_timer1_freq; - - - 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 = nps_get_timer_clk(node, &nps_timer1_freq, &clk); - if (ret) - return ret; - - ret = clocksource_mmio_init(nps_msu_reg_low_addr, "nps-tick", - nps_timer1_freq, 300, 32, nps_clksrc_read); - if (ret) { - pr_err("Couldn't register clock source.\n"); - clk_disable_unprepare(clk); - } - - return ret; -} - -TIMER_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer", - nps_setup_clocksource); -TIMER_OF_DECLARE(ezchip_nps400_clk_src, "ezchip,nps400-timer1", - nps_setup_clocksource); - -#ifdef CONFIG_EZNPS_MTM_EXT -#include <soc/nps/mtm.h> - -/* Timer related Aux registers */ -#define NPS_REG_TIMER0_TSI 0xFFFFF850 -#define NPS_REG_TIMER0_LIMIT 0x23 -#define NPS_REG_TIMER0_CTRL 0x22 -#define NPS_REG_TIMER0_CNT 0x21 - -/* - * Interrupt Enabled (IE) - re-arm the timer - * Not Halted (NH) - is cleared when working with JTAG (for debug) - */ -#define TIMER0_CTRL_IE BIT(0) -#define TIMER0_CTRL_NH BIT(1) - -static unsigned long nps_timer0_freq; -static unsigned long nps_timer0_irq; - -static void nps_clkevent_rm_thread(void) -{ - int thread; - unsigned int cflags, enabled_threads; - - hw_schd_save(&cflags); - - enabled_threads = read_aux_reg(NPS_REG_TIMER0_TSI); - - /* remove thread from TSI1 */ - thread = read_aux_reg(CTOP_AUX_THREAD_ID); - enabled_threads &= ~(1 << thread); - write_aux_reg(NPS_REG_TIMER0_TSI, enabled_threads); - - /* Acknowledge and if needed re-arm the timer */ - if (!enabled_threads) - write_aux_reg(NPS_REG_TIMER0_CTRL, TIMER0_CTRL_NH); - else - write_aux_reg(NPS_REG_TIMER0_CTRL, - TIMER0_CTRL_IE | TIMER0_CTRL_NH); - - hw_schd_restore(cflags); -} - -static void nps_clkevent_add_thread(unsigned long delta) -{ - int thread; - unsigned int cflags, enabled_threads; - - hw_schd_save(&cflags); - - /* add thread to TSI1 */ - thread = read_aux_reg(CTOP_AUX_THREAD_ID); - enabled_threads = read_aux_reg(NPS_REG_TIMER0_TSI); - enabled_threads |= (1 << thread); - write_aux_reg(NPS_REG_TIMER0_TSI, enabled_threads); - - /* set next timer event */ - write_aux_reg(NPS_REG_TIMER0_LIMIT, delta); - write_aux_reg(NPS_REG_TIMER0_CNT, 0); - write_aux_reg(NPS_REG_TIMER0_CTRL, - TIMER0_CTRL_IE | TIMER0_CTRL_NH); - - hw_schd_restore(cflags); -} - -/* - * Whenever anyone tries to change modes, we just mask interrupts - * and wait for the next event to get set. - */ -static int nps_clkevent_set_state(struct clock_event_device *dev) -{ - nps_clkevent_rm_thread(); - disable_percpu_irq(nps_timer0_irq); - - return 0; -} - -static int nps_clkevent_set_next_event(unsigned long delta, - struct clock_event_device *dev) -{ - nps_clkevent_add_thread(delta); - enable_percpu_irq(nps_timer0_irq, IRQ_TYPE_NONE); - - return 0; -} - -static DEFINE_PER_CPU(struct clock_event_device, nps_clockevent_device) = { - .name = "NPS Timer0", - .features = CLOCK_EVT_FEAT_ONESHOT, - .rating = 300, - .set_next_event = nps_clkevent_set_next_event, - .set_state_oneshot = nps_clkevent_set_state, - .set_state_oneshot_stopped = nps_clkevent_set_state, - .set_state_shutdown = nps_clkevent_set_state, - .tick_resume = nps_clkevent_set_state, -}; - -static irqreturn_t timer_irq_handler(int irq, void *dev_id) -{ - struct clock_event_device *evt = dev_id; - - nps_clkevent_rm_thread(); - evt->event_handler(evt); - - return IRQ_HANDLED; -} - -static int nps_timer_starting_cpu(unsigned int cpu) -{ - struct clock_event_device *evt = this_cpu_ptr(&nps_clockevent_device); - - evt->cpumask = cpumask_of(smp_processor_id()); - - clockevents_config_and_register(evt, nps_timer0_freq, 0, ULONG_MAX); - enable_percpu_irq(nps_timer0_irq, IRQ_TYPE_NONE); - - return 0; -} - -static int nps_timer_dying_cpu(unsigned int cpu) -{ - disable_percpu_irq(nps_timer0_irq); - return 0; -} - -static int __init nps_setup_clockevent(struct device_node *node) -{ - struct clk *clk; - int ret; - - nps_timer0_irq = irq_of_parse_and_map(node, 0); - if (nps_timer0_irq <= 0) { - pr_err("clockevent: missing irq\n"); - return -EINVAL; - } - - ret = nps_get_timer_clk(node, &nps_timer0_freq, &clk); - if (ret) - return ret; - - /* Needs apriori irq_set_percpu_devid() done in intc map function */ - ret = request_percpu_irq(nps_timer0_irq, timer_irq_handler, - "Timer0 (per-cpu-tick)", - &nps_clockevent_device); - if (ret) { - pr_err("Couldn't request irq\n"); - clk_disable_unprepare(clk); - return ret; - } - - ret = cpuhp_setup_state(CPUHP_AP_ARC_TIMER_STARTING, - "clockevents/nps:starting", - nps_timer_starting_cpu, - nps_timer_dying_cpu); - if (ret) { - pr_err("Failed to setup hotplug state\n"); - clk_disable_unprepare(clk); - free_percpu_irq(nps_timer0_irq, &nps_clockevent_device); - return ret; - } - - return 0; -} - -TIMER_OF_DECLARE(ezchip_nps400_clk_evt, "ezchip,nps400-timer0", - nps_setup_clockevent); -#endif /* CONFIG_EZNPS_MTM_EXT */ diff --git a/drivers/clocksource/timer-orion.c b/drivers/clocksource/timer-orion.c index d01ff4181867..5101e834d78f 100644 --- a/drivers/clocksource/timer-orion.c +++ b/drivers/clocksource/timer-orion.c @@ -143,7 +143,8 @@ static int __init orion_timer_init(struct device_node *np) irq = irq_of_parse_and_map(np, 1); if (irq <= 0) { pr_err("%pOFn: unable to parse timer1 irq\n", np); - return -EINVAL; + ret = -EINVAL; + goto out_unprep_clk; } rate = clk_get_rate(clk); @@ -160,7 +161,7 @@ static int __init orion_timer_init(struct device_node *np) clocksource_mmio_readl_down); if (ret) { pr_err("Failed to initialize mmio timer\n"); - return ret; + goto out_unprep_clk; } sched_clock_register(orion_read_sched_clock, 32, rate); @@ -170,7 +171,7 @@ static int __init orion_timer_init(struct device_node *np) "orion_event", NULL); if (ret) { pr_err("%pOFn: unable to setup irq\n", np); - return ret; + goto out_unprep_clk; } ticks_per_jiffy = (clk_get_rate(clk) + HZ/2) / HZ; @@ -183,5 +184,9 @@ static int __init orion_timer_init(struct device_node *np) orion_delay_timer_init(rate); return 0; + +out_unprep_clk: + clk_disable_unprepare(clk); + return ret; } TIMER_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init); diff --git a/drivers/clocksource/timer-sp804.c b/drivers/clocksource/timer-sp804.c index 6e8ad4a4ea3c..401d592e85f5 100644 --- a/drivers/clocksource/timer-sp804.c +++ b/drivers/clocksource/timer-sp804.c @@ -5,6 +5,9 @@ * Copyright (C) 1999 - 2003 ARM Limited * Copyright (C) 2000 Deep Blue Solutions Ltd */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/clk.h> #include <linux/clocksource.h> #include <linux/clockchips.h> @@ -34,8 +37,7 @@ #define HISI_TIMER_BGLOAD 0x20 #define HISI_TIMER_BGLOAD_H 0x24 - -struct sp804_timer __initdata arm_sp804_timer = { +static struct sp804_timer arm_sp804_timer __initdata = { .load = TIMER_LOAD, .value = TIMER_VALUE, .ctrl = TIMER_CTRL, @@ -44,7 +46,7 @@ struct sp804_timer __initdata arm_sp804_timer = { .width = 32, }; -struct sp804_timer __initdata hisi_sp804_timer = { +static struct sp804_timer hisi_sp804_timer __initdata = { .load = HISI_TIMER_LOAD, .load_h = HISI_TIMER_LOAD_H, .value = HISI_TIMER_VALUE, @@ -59,40 +61,23 @@ static struct sp804_clkevt sp804_clkevt[NR_TIMERS]; static long __init sp804_get_clock_rate(struct clk *clk, const char *name) { - long rate; int err; if (!clk) clk = clk_get_sys("sp804", name); if (IS_ERR(clk)) { - pr_err("sp804: %s clock not found: %ld\n", name, PTR_ERR(clk)); + pr_err("%s clock not found: %ld\n", name, PTR_ERR(clk)); return PTR_ERR(clk); } - err = clk_prepare(clk); - if (err) { - pr_err("sp804: clock failed to prepare: %d\n", err); - clk_put(clk); - return err; - } - - err = clk_enable(clk); + err = clk_prepare_enable(clk); if (err) { - pr_err("sp804: clock failed to enable: %d\n", err); - clk_unprepare(clk); + pr_err("clock failed to enable: %d\n", err); clk_put(clk); return err; } - rate = clk_get_rate(clk); - if (rate < 0) { - pr_err("sp804: clock failed to get rate: %ld\n", rate); - clk_disable(clk); - clk_unprepare(clk); - clk_put(clk); - } - - return rate; + return clk_get_rate(clk); } static struct sp804_clkevt * __init sp804_clkevt_get(void __iomem *base) @@ -117,10 +102,10 @@ static u64 notrace sp804_read(void) return ~readl_relaxed(sched_clkevt->value); } -int __init sp804_clocksource_and_sched_clock_init(void __iomem *base, - const char *name, - struct clk *clk, - int use_sched_clock) +static int __init sp804_clocksource_and_sched_clock_init(void __iomem *base, + const char *name, + struct clk *clk, + int use_sched_clock) { long rate; struct sp804_clkevt *clkevt; @@ -216,8 +201,8 @@ static struct clock_event_device sp804_clockevent = { .rating = 300, }; -int __init sp804_clockevents_init(void __iomem *base, unsigned int irq, - struct clk *clk, const char *name) +static int __init sp804_clockevents_init(void __iomem *base, unsigned int irq, + struct clk *clk, const char *name) { struct clock_event_device *evt = &sp804_clockevent; long rate; @@ -236,7 +221,7 @@ int __init sp804_clockevents_init(void __iomem *base, unsigned int irq, if (request_irq(irq, sp804_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL, "timer", &sp804_clockevent)) - pr_err("%s: request_irq() failed\n", "timer"); + pr_err("request_irq() failed\n"); clockevents_config_and_register(evt, rate, 0xf, 0xffffffff); return 0; @@ -298,7 +283,7 @@ static int __init sp804_of_init(struct device_node *np, struct sp804_timer *time if (of_clk_get_parent_count(np) == 3) { clk2 = of_clk_get(np, 1); if (IS_ERR(clk2)) { - pr_err("sp804: %pOFn clock not found: %d\n", np, + pr_err("%pOFn clock not found: %d\n", np, (int)PTR_ERR(clk2)); clk2 = NULL; } diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index bfb57464118d..bb8f319b09fb 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -6,7 +6,6 @@ ccflags-$(CONFIG_RTC_DEBUG) := -DDEBUG obj-$(CONFIG_RTC_LIB) += lib.o -obj-$(CONFIG_RTC_SYSTOHC) += systohc.o obj-$(CONFIG_RTC_CLASS) += rtc-core.o obj-$(CONFIG_RTC_MC146818_LIB) += rtc-mc146818-lib.o rtc-core-y := class.o interface.o diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 7c88d190c51f..5855aa2eef62 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -200,8 +200,13 @@ static struct rtc_device *rtc_allocate_device(void) device_initialize(&rtc->dev); - /* Drivers can revise this default after allocating the device. */ - rtc->set_offset_nsec = NSEC_PER_SEC / 2; + /* + * Drivers can revise this default after allocating the device. + * The default is what most RTCs do: Increment seconds exactly one + * second after the write happened. This adds a default transport + * time of 5ms which is at least halfways close to reality. + */ + rtc->set_offset_nsec = NSEC_PER_SEC + 5 * NSEC_PER_MSEC; rtc->irq_freq = 1; rtc->max_user_freq = 64; diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index c633319cdb91..c5bcd2adc9fe 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -868,6 +868,9 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) if (retval) goto cleanup2; + /* Set the sync offset for the periodic 11min update correct */ + cmos_rtc.rtc->set_offset_nsec = NSEC_PER_SEC / 2; + /* export at least the first block of NVRAM */ nvmem_cfg.size = address_space - NVRAM_OFFSET; if (rtc_nvmem_register(cmos_rtc.rtc, &nvmem_cfg)) diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c index 2ecd8752b088..972a5b9a629d 100644 --- a/drivers/rtc/rtc-mc146818-lib.c +++ b/drivers/rtc/rtc-mc146818-lib.c @@ -8,41 +8,41 @@ #include <linux/acpi.h> #endif -/* - * Returns true if a clock update is in progress - */ -static inline unsigned char mc146818_is_updating(void) -{ - unsigned char uip; - unsigned long flags; - - spin_lock_irqsave(&rtc_lock, flags); - uip = (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP); - spin_unlock_irqrestore(&rtc_lock, flags); - return uip; -} - unsigned int mc146818_get_time(struct rtc_time *time) { unsigned char ctrl; unsigned long flags; unsigned char century = 0; + bool retry; #ifdef CONFIG_MACH_DECSTATION unsigned int real_year; #endif +again: + spin_lock_irqsave(&rtc_lock, flags); /* - * read RTC once any update in progress is done. The update - * can take just over 2ms. We wait 20ms. There is no need to - * to poll-wait (up to 1s - eeccch) for the falling edge of RTC_UIP. - * If you need to know *exactly* when a second has started, enable - * periodic update complete interrupts, (via ioctl) and then - * immediately read /dev/rtc which will block until you get the IRQ. - * Once the read clears, read the RTC time (again via ioctl). Easy. + * Check whether there is an update in progress during which the + * readout is unspecified. The maximum update time is ~2ms. Poll + * every msec for completion. + * + * Store the second value before checking UIP so a long lasting NMI + * which happens to hit after the UIP check cannot make an update + * cycle invisible. */ - if (mc146818_is_updating()) - mdelay(20); + time->tm_sec = CMOS_READ(RTC_SECONDS); + + if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) { + spin_unlock_irqrestore(&rtc_lock, flags); + mdelay(1); + goto again; + } + + /* Revalidate the above readout */ + if (time->tm_sec != CMOS_READ(RTC_SECONDS)) { + spin_unlock_irqrestore(&rtc_lock, flags); + goto again; + } /* * Only the values that we read from the RTC are set. We leave @@ -50,8 +50,6 @@ unsigned int mc146818_get_time(struct rtc_time *time) * RTC has RTC_DAY_OF_WEEK, we ignore it, as it is only updated * by the RTC when initially set to a non-zero value. */ - spin_lock_irqsave(&rtc_lock, flags); - time->tm_sec = CMOS_READ(RTC_SECONDS); time->tm_min = CMOS_READ(RTC_MINUTES); time->tm_hour = CMOS_READ(RTC_HOURS); time->tm_mday = CMOS_READ(RTC_DAY_OF_MONTH); @@ -66,8 +64,24 @@ unsigned int mc146818_get_time(struct rtc_time *time) century = CMOS_READ(acpi_gbl_FADT.century); #endif ctrl = CMOS_READ(RTC_CONTROL); + /* + * Check for the UIP bit again. If it is set now then + * the above values may contain garbage. + */ + retry = CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP; + /* + * A NMI might have interrupted the above sequence so check whether + * the seconds value has changed which indicates that the NMI took + * longer than the UIP bit was set. Unlikely, but possible and + * there is also virt... + */ + retry |= time->tm_sec != CMOS_READ(RTC_SECONDS); + spin_unlock_irqrestore(&rtc_lock, flags); + if (retry) + goto again; + if (!(ctrl & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { time->tm_sec = bcd2bin(time->tm_sec); @@ -121,7 +135,6 @@ int mc146818_set_time(struct rtc_time *time) if (yrs > 255) /* They are unsigned */ return -EINVAL; - spin_lock_irqsave(&rtc_lock, flags); #ifdef CONFIG_MACH_DECSTATION real_yrs = yrs; leap_yr = ((!((yrs + 1900) % 4) && ((yrs + 1900) % 100)) || @@ -150,10 +163,8 @@ int mc146818_set_time(struct rtc_time *time) /* These limits and adjustments are independent of * whether the chip is in binary mode or not. */ - if (yrs > 169) { - spin_unlock_irqrestore(&rtc_lock, flags); + if (yrs > 169) return -EINVAL; - } if (yrs >= 100) yrs -= 100; @@ -169,6 +180,7 @@ int mc146818_set_time(struct rtc_time *time) century = bin2bcd(century); } + spin_lock_irqsave(&rtc_lock, flags); save_control = CMOS_READ(RTC_CONTROL); CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL); save_freq_select = CMOS_READ(RTC_FREQ_SELECT); diff --git a/drivers/rtc/systohc.c b/drivers/rtc/systohc.c deleted file mode 100644 index 8b70f0520e13..000000000000 --- a/drivers/rtc/systohc.c +++ /dev/null @@ -1,61 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include <linux/rtc.h> -#include <linux/time.h> - -/** - * rtc_set_ntp_time - Save NTP synchronized time to the RTC - * @now: Current time of day - * @target_nsec: pointer for desired now->tv_nsec value - * - * Replacement for the NTP platform function update_persistent_clock64 - * that stores time for later retrieval by rtc_hctosys. - * - * Returns 0 on successful RTC update, -ENODEV if a RTC update is not - * possible at all, and various other -errno for specific temporary failure - * cases. - * - * -EPROTO is returned if now.tv_nsec is not close enough to *target_nsec. - * - * If temporary failure is indicated the caller should try again 'soon' - */ -int rtc_set_ntp_time(struct timespec64 now, unsigned long *target_nsec) -{ - struct rtc_device *rtc; - struct rtc_time tm; - struct timespec64 to_set; - int err = -ENODEV; - bool ok; - - rtc = rtc_class_open(CONFIG_RTC_SYSTOHC_DEVICE); - if (!rtc) - goto out_err; - - if (!rtc->ops || !rtc->ops->set_time) - goto out_close; - - /* Compute the value of tv_nsec we require the caller to supply in - * now.tv_nsec. This is the value such that (now + - * set_offset_nsec).tv_nsec == 0. - */ - set_normalized_timespec64(&to_set, 0, -rtc->set_offset_nsec); - *target_nsec = to_set.tv_nsec; - - /* The ntp code must call this with the correct value in tv_nsec, if - * it does not we update target_nsec and return EPROTO to make the ntp - * code try again later. - */ - ok = rtc_tv_nsec_ok(rtc->set_offset_nsec, &to_set, &now); - if (!ok) { - err = -EPROTO; - goto out_close; - } - - rtc_time64_to_tm(to_set.tv_sec, &tm); - - err = rtc_set_time(rtc, &tm); - -out_close: - rtc_class_close(rtc); -out_err: - return err; -} diff --git a/include/dt-bindings/clock/ingenic,sysost.h b/include/dt-bindings/clock/ingenic,sysost.h index 9ac88e90babf..063791b01ab3 100644 --- a/include/dt-bindings/clock/ingenic,sysost.h +++ b/include/dt-bindings/clock/ingenic,sysost.h @@ -1,12 +1,16 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * This header provides clock numbers for the ingenic,tcu DT binding. + * This header provides clock numbers for the Ingenic OST DT binding. */ #ifndef __DT_BINDINGS_CLOCK_INGENIC_OST_H__ #define __DT_BINDINGS_CLOCK_INGENIC_OST_H__ -#define OST_CLK_PERCPU_TIMER 0 -#define OST_CLK_GLOBAL_TIMER 1 +#define OST_CLK_PERCPU_TIMER 1 +#define OST_CLK_GLOBAL_TIMER 0 +#define OST_CLK_PERCPU_TIMER0 1 +#define OST_CLK_PERCPU_TIMER1 2 +#define OST_CLK_PERCPU_TIMER2 3 +#define OST_CLK_PERCPU_TIMER3 4 #endif /* __DT_BINDINGS_CLOCK_INGENIC_OST_H__ */ diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 107cedd7019a..bb5e7b0a4274 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -447,6 +447,10 @@ static inline void hrtimer_restart(struct hrtimer *timer) /* Query timers: */ extern ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust); +/** + * hrtimer_get_remaining - get remaining time for the timer + * @timer: the timer to read + */ static inline ktime_t hrtimer_get_remaining(const struct hrtimer *timer) { return __hrtimer_get_remaining(timer, false); @@ -458,7 +462,7 @@ extern u64 hrtimer_next_event_without(const struct hrtimer *exclude); extern bool hrtimer_active(const struct hrtimer *timer); /** - * hrtimer_is_queued = check, whether the timer is on one of the queues + * hrtimer_is_queued - check, whether the timer is on one of the queues * @timer: Timer to check * * Returns: True if the timer is queued, false otherwise diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 22d1575e4991..b829382de6c3 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -110,13 +110,36 @@ struct rtc_device { /* Some hardware can't support UIE mode */ int uie_unsupported; - /* Number of nsec it takes to set the RTC clock. This influences when - * the set ops are called. An offset: - * - of 0.5 s will call RTC set for wall clock time 10.0 s at 9.5 s - * - of 1.5 s will call RTC set for wall clock time 10.0 s at 8.5 s - * - of -0.5 s will call RTC set for wall clock time 10.0 s at 10.5 s + /* + * This offset specifies the update timing of the RTC. + * + * tsched t1 write(t2.tv_sec - 1sec)) t2 RTC increments seconds + * + * The offset defines how tsched is computed so that the write to + * the RTC (t2.tv_sec - 1sec) is correct versus the time required + * for the transport of the write and the time which the RTC needs + * to increment seconds the first time after the write (t2). + * + * For direct accessible RTCs tsched ~= t1 because the write time + * is negligible. For RTCs behind slow busses the transport time is + * significant and has to be taken into account. + * + * The time between the write (t1) and the first increment after + * the write (t2) is RTC specific. For a MC146818 RTC it's 500ms, + * for many others it's exactly 1 second. Consult the datasheet. + * + * The value of this offset is also used to calculate the to be + * written value (t2.tv_sec - 1sec) at tsched. + * + * The default value for this is NSEC_PER_SEC + 10 msec default + * transport time. The offset can be adjusted by drivers so the + * calculation for the to be written value at tsched becomes + * correct: + * + * newval = tsched + set_offset_nsec - NSEC_PER_SEC + * and (tsched + set_offset_nsec) % NSEC_PER_SEC == 0 */ - long set_offset_nsec; + unsigned long set_offset_nsec; bool registered; @@ -165,7 +188,6 @@ int __rtc_register_device(struct module *owner, struct rtc_device *rtc); extern int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm); extern int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm); -extern int rtc_set_ntp_time(struct timespec64 now, unsigned long *target_nsec); int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm); extern int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alrm); @@ -205,39 +227,6 @@ static inline bool is_leap_year(unsigned int year) return (!(year % 4) && (year % 100)) || !(year % 400); } -/* Determine if we can call to driver to set the time. Drivers can only be - * called to set a second aligned time value, and the field set_offset_nsec - * specifies how far away from the second aligned time to call the driver. - * - * This also computes 'to_set' which is the time we are trying to set, and has - * a zero in tv_nsecs, such that: - * to_set - set_delay_nsec == now +/- FUZZ - * - */ -static inline bool rtc_tv_nsec_ok(s64 set_offset_nsec, - struct timespec64 *to_set, - const struct timespec64 *now) -{ - /* Allowed error in tv_nsec, arbitarily set to 5 jiffies in ns. */ - const unsigned long TIME_SET_NSEC_FUZZ = TICK_NSEC * 5; - struct timespec64 delay = {.tv_sec = 0, - .tv_nsec = set_offset_nsec}; - - *to_set = timespec64_add(*now, delay); - - if (to_set->tv_nsec < TIME_SET_NSEC_FUZZ) { - to_set->tv_nsec = 0; - return true; - } - - if (to_set->tv_nsec > NSEC_PER_SEC - TIME_SET_NSEC_FUZZ) { - to_set->tv_sec++; - to_set->tv_nsec = 0; - return true; - } - return false; -} - #define rtc_register_device(device) \ __rtc_register_device(THIS_MODULE, device) diff --git a/include/linux/timekeeping.h b/include/linux/timekeeping.h index 7f7e4a3f4394..929d3f3937c0 100644 --- a/include/linux/timekeeping.h +++ b/include/linux/timekeeping.h @@ -303,6 +303,8 @@ extern int persistent_clock_is_local; extern void read_persistent_clock64(struct timespec64 *ts); void read_persistent_wall_and_boot_offset(struct timespec64 *wall_clock, struct timespec64 *boot_offset); +#ifdef CONFIG_GENERIC_CMOS_UPDATE extern int update_persistent_clock64(struct timespec64 now); +#endif #endif diff --git a/include/linux/timer.h b/include/linux/timer.h index d10bc7e73b41..fda13c9d1256 100644 --- a/include/linux/timer.h +++ b/include/linux/timer.h @@ -193,7 +193,6 @@ extern int try_to_del_timer_sync(struct timer_list *timer); #define del_singleshot_timer_sync(t) del_timer_sync(t) extern void init_timers(void); -extern void run_local_timers(void); struct hrtimer; extern enum hrtimer_restart it_real_fn(struct hrtimer *); diff --git a/include/linux/timex.h b/include/linux/timex.h index ce0859763670..9c2e54faf9b7 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -157,7 +157,6 @@ extern int do_clock_adjtime(const clockid_t which_clock, struct __kernel_timex * extern void hardpps(const struct timespec64 *, const struct timespec64 *); int read_current_timer(unsigned long *timer_val); -void ntp_notify_cmos_timer(void); /* The clock frequency of the i8253/i8254 PIT */ #define PIT_TICK_RATE 1193182ul diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 387b4bef7dd1..743c852e10f2 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1284,7 +1284,7 @@ int hrtimer_cancel(struct hrtimer *timer) EXPORT_SYMBOL_GPL(hrtimer_cancel); /** - * hrtimer_get_remaining - get remaining time for the timer + * __hrtimer_get_remaining - get remaining time for the timer * @timer: the timer to read * @adjust: adjust relative timers when CONFIG_TIME_LOW_RES=y */ diff --git a/kernel/time/jiffies.c b/kernel/time/jiffies.c index eddcf4970444..a5cffe2a1770 100644 --- a/kernel/time/jiffies.c +++ b/kernel/time/jiffies.c @@ -59,7 +59,8 @@ static struct clocksource clocksource_jiffies = { }; __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock); -__cacheline_aligned_in_smp seqcount_t jiffies_seq; +__cacheline_aligned_in_smp seqcount_raw_spinlock_t jiffies_seq = + SEQCNT_RAW_SPINLOCK_ZERO(jiffies_seq, &jiffies_lock); #if (BITS_PER_LONG < 64) u64 get_jiffies_64(void) diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 069ca78fb0bf..7404d3831527 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -494,65 +494,74 @@ out: return leap; } +#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) static void sync_hw_clock(struct work_struct *work); -static DECLARE_DELAYED_WORK(sync_work, sync_hw_clock); - -static void sched_sync_hw_clock(struct timespec64 now, - unsigned long target_nsec, bool fail) +static DECLARE_WORK(sync_work, sync_hw_clock); +static struct hrtimer sync_hrtimer; +#define SYNC_PERIOD_NS (11UL * 60 * NSEC_PER_SEC) +static enum hrtimer_restart sync_timer_callback(struct hrtimer *timer) { - struct timespec64 next; - - ktime_get_real_ts64(&next); - if (!fail) - next.tv_sec = 659; - else { - /* - * Try again as soon as possible. Delaying long periods - * decreases the accuracy of the work queue timer. Due to this - * the algorithm is very likely to require a short-sleep retry - * after the above long sleep to synchronize ts_nsec. - */ - next.tv_sec = 0; - } - - /* Compute the needed delay that will get to tv_nsec == target_nsec */ - next.tv_nsec = target_nsec - next.tv_nsec; - if (next.tv_nsec <= 0) - next.tv_nsec += NSEC_PER_SEC; - if (next.tv_nsec >= NSEC_PER_SEC) { - next.tv_sec++; - next.tv_nsec -= NSEC_PER_SEC; - } + queue_work(system_power_efficient_wq, &sync_work); - queue_delayed_work(system_power_efficient_wq, &sync_work, - timespec64_to_jiffies(&next)); + return HRTIMER_NORESTART; } -static void sync_rtc_clock(void) +static void sched_sync_hw_clock(unsigned long offset_nsec, bool retry) { - unsigned long target_nsec; - struct timespec64 adjust, now; - int rc; + ktime_t exp = ktime_set(ktime_get_real_seconds(), 0); - if (!IS_ENABLED(CONFIG_RTC_SYSTOHC)) - return; + if (retry) + exp = ktime_add_ns(exp, 2 * NSEC_PER_SEC - offset_nsec); + else + exp = ktime_add_ns(exp, SYNC_PERIOD_NS - offset_nsec); - ktime_get_real_ts64(&now); + hrtimer_start(&sync_hrtimer, exp, HRTIMER_MODE_ABS); +} - adjust = now; - if (persistent_clock_is_local) - adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); +/* + * Check whether @now is correct versus the required time to update the RTC + * and calculate the value which needs to be written to the RTC so that the + * next seconds increment of the RTC after the write is aligned with the next + * seconds increment of clock REALTIME. + * + * tsched t1 write(t2.tv_sec - 1sec)) t2 RTC increments seconds + * + * t2.tv_nsec == 0 + * tsched = t2 - set_offset_nsec + * newval = t2 - NSEC_PER_SEC + * + * ==> neval = tsched + set_offset_nsec - NSEC_PER_SEC + * + * As the execution of this code is not guaranteed to happen exactly at + * tsched this allows it to happen within a fuzzy region: + * + * abs(now - tsched) < FUZZ + * + * If @now is not inside the allowed window the function returns false. + */ +static inline bool rtc_tv_nsec_ok(unsigned long set_offset_nsec, + struct timespec64 *to_set, + const struct timespec64 *now) +{ + /* Allowed error in tv_nsec, arbitarily set to 5 jiffies in ns. */ + const unsigned long TIME_SET_NSEC_FUZZ = TICK_NSEC * 5; + struct timespec64 delay = {.tv_sec = -1, + .tv_nsec = set_offset_nsec}; - /* - * The current RTC in use will provide the target_nsec it wants to be - * called at, and does rtc_tv_nsec_ok internally. - */ - rc = rtc_set_ntp_time(adjust, &target_nsec); - if (rc == -ENODEV) - return; + *to_set = timespec64_add(*now, delay); + + if (to_set->tv_nsec < TIME_SET_NSEC_FUZZ) { + to_set->tv_nsec = 0; + return true; + } - sched_sync_hw_clock(now, target_nsec, rc); + if (to_set->tv_nsec > NSEC_PER_SEC - TIME_SET_NSEC_FUZZ) { + to_set->tv_sec++; + to_set->tv_nsec = 0; + return true; + } + return false; } #ifdef CONFIG_GENERIC_CMOS_UPDATE @@ -560,48 +569,47 @@ int __weak update_persistent_clock64(struct timespec64 now64) { return -ENODEV; } +#else +static inline int update_persistent_clock64(struct timespec64 now64) +{ + return -ENODEV; +} #endif -static bool sync_cmos_clock(void) +#ifdef CONFIG_RTC_SYSTOHC +/* Save NTP synchronized time to the RTC */ +static int update_rtc(struct timespec64 *to_set, unsigned long *offset_nsec) { - static bool no_cmos; - struct timespec64 now; - struct timespec64 adjust; - int rc = -EPROTO; - long target_nsec = NSEC_PER_SEC / 2; + struct rtc_device *rtc; + struct rtc_time tm; + int err = -ENODEV; - if (!IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE)) - return false; + rtc = rtc_class_open(CONFIG_RTC_SYSTOHC_DEVICE); + if (!rtc) + return -ENODEV; - if (no_cmos) - return false; + if (!rtc->ops || !rtc->ops->set_time) + goto out_close; - /* - * Historically update_persistent_clock64() has followed x86 - * semantics, which match the MC146818A/etc RTC. This RTC will store - * 'adjust' and then in .5s it will advance once second. - * - * Architectures are strongly encouraged to use rtclib and not - * implement this legacy API. - */ - ktime_get_real_ts64(&now); - if (rtc_tv_nsec_ok(-1 * target_nsec, &adjust, &now)) { - if (persistent_clock_is_local) - adjust.tv_sec -= (sys_tz.tz_minuteswest * 60); - rc = update_persistent_clock64(adjust); - /* - * The machine does not support update_persistent_clock64 even - * though it defines CONFIG_GENERIC_CMOS_UPDATE. - */ - if (rc == -ENODEV) { - no_cmos = true; - return false; - } + /* First call might not have the correct offset */ + if (*offset_nsec == rtc->set_offset_nsec) { + rtc_time64_to_tm(to_set->tv_sec, &tm); + err = rtc_set_time(rtc, &tm); + } else { + /* Store the update offset and let the caller try again */ + *offset_nsec = rtc->set_offset_nsec; + err = -EAGAIN; } - - sched_sync_hw_clock(now, target_nsec, rc); - return true; +out_close: + rtc_class_close(rtc); + return err; +} +#else +static inline int update_rtc(struct timespec64 *to_set, unsigned long *offset_nsec) +{ + return -ENODEV; } +#endif /* * If we have an externally synchronized Linux clock, then update RTC clock @@ -613,24 +621,64 @@ static bool sync_cmos_clock(void) */ static void sync_hw_clock(struct work_struct *work) { - if (!ntp_synced()) - return; + /* + * The default synchronization offset is 500ms for the deprecated + * update_persistent_clock64() under the assumption that it uses + * the infamous CMOS clock (MC146818). + */ + static unsigned long offset_nsec = NSEC_PER_SEC / 2; + struct timespec64 now, to_set; + int res = -EAGAIN; - if (sync_cmos_clock()) + /* + * Don't update if STA_UNSYNC is set and if ntp_notify_cmos_timer() + * managed to schedule the work between the timer firing and the + * work being able to rearm the timer. Wait for the timer to expire. + */ + if (!ntp_synced() || hrtimer_is_queued(&sync_hrtimer)) return; - sync_rtc_clock(); + ktime_get_real_ts64(&now); + /* If @now is not in the allowed window, try again */ + if (!rtc_tv_nsec_ok(offset_nsec, &to_set, &now)) + goto rearm; + + /* Take timezone adjusted RTCs into account */ + if (persistent_clock_is_local) + to_set.tv_sec -= (sys_tz.tz_minuteswest * 60); + + /* Try the legacy RTC first. */ + res = update_persistent_clock64(to_set); + if (res != -ENODEV) + goto rearm; + + /* Try the RTC class */ + res = update_rtc(&to_set, &offset_nsec); + if (res == -ENODEV) + return; +rearm: + sched_sync_hw_clock(offset_nsec, res != 0); } void ntp_notify_cmos_timer(void) { - if (!ntp_synced()) - return; + /* + * When the work is currently executed but has not yet the timer + * rearmed this queues the work immediately again. No big issue, + * just a pointless work scheduled. + */ + if (ntp_synced() && !hrtimer_is_queued(&sync_hrtimer)) + queue_work(system_power_efficient_wq, &sync_work); +} - if (IS_ENABLED(CONFIG_GENERIC_CMOS_UPDATE) || - IS_ENABLED(CONFIG_RTC_SYSTOHC)) - queue_delayed_work(system_power_efficient_wq, &sync_work, 0); +static void __init ntp_init_cmos_sync(void) +{ + hrtimer_init(&sync_hrtimer, CLOCK_REALTIME, HRTIMER_MODE_ABS); + sync_hrtimer.function = sync_timer_callback; } +#else /* CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) */ +static inline void __init ntp_init_cmos_sync(void) { } +#endif /* !CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) */ /* * Propagate a new txc->status value into the NTP state: @@ -1044,4 +1092,5 @@ __setup("ntp_tick_adj=", ntp_tick_adj_setup); void __init ntp_init(void) { ntp_clear(); + ntp_init_cmos_sync(); } diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h index 908ecaa65fc3..23d1b74c3065 100644 --- a/kernel/time/ntp_internal.h +++ b/kernel/time/ntp_internal.h @@ -12,4 +12,11 @@ extern int __do_adjtimex(struct __kernel_timex *txc, const struct timespec64 *ts, s32 *time_tai, struct audit_ntp_data *ad); extern void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts); + +#if defined(CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) +extern void ntp_notify_cmos_timer(void); +#else +static inline void ntp_notify_cmos_timer(void) { } +#endif + #endif /* _LINUX_NTP_INTERNAL_H */ diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 36d7464c8962..5a23829372c7 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -331,7 +331,7 @@ static void tick_handle_periodic_broadcast(struct clock_event_device *dev) bc_local = tick_do_periodic_broadcast(); if (clockevent_state_oneshot(dev)) { - ktime_t next = ktime_add(dev->next_event, tick_period); + ktime_t next = ktime_add_ns(dev->next_event, TICK_NSEC); clockevents_program_event(dev, next, true); } @@ -877,6 +877,22 @@ static void tick_broadcast_init_next_event(struct cpumask *mask, } } +static inline ktime_t tick_get_next_period(void) +{ + ktime_t next; + + /* + * Protect against concurrent updates (store /load tearing on + * 32bit). It does not matter if the time is already in the + * past. The broadcast device which is about to be programmed will + * fire in any case. + */ + raw_spin_lock(&jiffies_lock); + next = tick_next_period; + raw_spin_unlock(&jiffies_lock); + return next; +} + /** * tick_broadcast_setup_oneshot - setup the broadcast device */ @@ -905,10 +921,11 @@ static void tick_broadcast_setup_oneshot(struct clock_event_device *bc) tick_broadcast_oneshot_mask, tmpmask); if (was_periodic && !cpumask_empty(tmpmask)) { + ktime_t nextevt = tick_get_next_period(); + clockevents_switch_state(bc, CLOCK_EVT_STATE_ONESHOT); - tick_broadcast_init_next_event(tmpmask, - tick_next_period); - tick_broadcast_set_event(bc, cpu, tick_next_period); + tick_broadcast_init_next_event(tmpmask, nextevt); + tick_broadcast_set_event(bc, cpu, nextevt); } else bc->next_event = KTIME_MAX; } else { diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 6c9c342dd0e5..a03764df5366 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -27,10 +27,11 @@ */ DEFINE_PER_CPU(struct tick_device, tick_cpu_device); /* - * Tick next event: keeps track of the tick time + * Tick next event: keeps track of the tick time. It's updated by the + * CPU which handles the tick and protected by jiffies_lock. There is + * no requirement to write hold the jiffies seqcount for it. */ ktime_t tick_next_period; -ktime_t tick_period; /* * tick_do_timer_cpu is a timer core internal variable which holds the CPU NR @@ -88,7 +89,7 @@ static void tick_periodic(int cpu) write_seqcount_begin(&jiffies_seq); /* Keep track of the next tick event */ - tick_next_period = ktime_add(tick_next_period, tick_period); + tick_next_period = ktime_add_ns(tick_next_period, TICK_NSEC); do_timer(1); write_seqcount_end(&jiffies_seq); @@ -127,7 +128,7 @@ void tick_handle_periodic(struct clock_event_device *dev) * Setup the next period for devices, which do not have * periodic mode: */ - next = ktime_add(next, tick_period); + next = ktime_add_ns(next, TICK_NSEC); if (!clockevents_program_event(dev, next, false)) return; @@ -173,7 +174,7 @@ void tick_setup_periodic(struct clock_event_device *dev, int broadcast) for (;;) { if (!clockevents_program_event(dev, next, false)) return; - next = ktime_add(next, tick_period); + next = ktime_add_ns(next, TICK_NSEC); } } } @@ -220,7 +221,6 @@ static void tick_setup_device(struct tick_device *td, tick_do_timer_cpu = cpu; tick_next_period = ktime_get(); - tick_period = NSEC_PER_SEC / HZ; #ifdef CONFIG_NO_HZ_FULL /* * The boot CPU may be nohz_full, in which case set diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 7b2496136729..7a981c9e87a4 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -15,7 +15,6 @@ DECLARE_PER_CPU(struct tick_device, tick_cpu_device); extern ktime_t tick_next_period; -extern ktime_t tick_period; extern int tick_do_timer_cpu __read_mostly; extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 81632cd5e3b7..a9e68936822d 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -20,6 +20,7 @@ #include <linux/sched/clock.h> #include <linux/sched/stat.h> #include <linux/sched/nohz.h> +#include <linux/sched/loadavg.h> #include <linux/module.h> #include <linux/irq_work.h> #include <linux/posix-timers.h> @@ -44,7 +45,9 @@ struct tick_sched *tick_get_tick_sched(int cpu) #if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS) /* - * The time, when the last jiffy update happened. Protected by jiffies_lock. + * The time, when the last jiffy update happened. Write access must hold + * jiffies_lock and jiffies_seq. tick_nohz_next_event() needs to get a + * consistent view of jiffies and last_jiffies_update. */ static ktime_t last_jiffies_update; @@ -53,50 +56,97 @@ static ktime_t last_jiffies_update; */ static void tick_do_update_jiffies64(ktime_t now) { - unsigned long ticks = 0; - ktime_t delta; + unsigned long ticks = 1; + ktime_t delta, nextp; /* - * Do a quick check without holding jiffies_lock: - * The READ_ONCE() pairs with two updates done later in this function. + * 64bit can do a quick check without holding jiffies lock and + * without looking at the sequence count. The smp_load_acquire() + * pairs with the update done later in this function. + * + * 32bit cannot do that because the store of tick_next_period + * consists of two 32bit stores and the first store could move it + * to a random point in the future. */ - delta = ktime_sub(now, READ_ONCE(last_jiffies_update)); - if (delta < tick_period) - return; + if (IS_ENABLED(CONFIG_64BIT)) { + if (ktime_before(now, smp_load_acquire(&tick_next_period))) + return; + } else { + unsigned int seq; - /* Reevaluate with jiffies_lock held */ + /* + * Avoid contention on jiffies_lock and protect the quick + * check with the sequence count. + */ + do { + seq = read_seqcount_begin(&jiffies_seq); + nextp = tick_next_period; + } while (read_seqcount_retry(&jiffies_seq, seq)); + + if (ktime_before(now, nextp)) + return; + } + + /* Quick check failed, i.e. update is required. */ raw_spin_lock(&jiffies_lock); + /* + * Reevaluate with the lock held. Another CPU might have done the + * update already. + */ + if (ktime_before(now, tick_next_period)) { + raw_spin_unlock(&jiffies_lock); + return; + } + write_seqcount_begin(&jiffies_seq); - delta = ktime_sub(now, last_jiffies_update); - if (delta >= tick_period) { + delta = ktime_sub(now, tick_next_period); + if (unlikely(delta >= TICK_NSEC)) { + /* Slow path for long idle sleep times */ + s64 incr = TICK_NSEC; - delta = ktime_sub(delta, tick_period); - /* Pairs with the lockless read in this function. */ - WRITE_ONCE(last_jiffies_update, - ktime_add(last_jiffies_update, tick_period)); + ticks += ktime_divns(delta, incr); - /* Slow path for long timeouts */ - if (unlikely(delta >= tick_period)) { - s64 incr = ktime_to_ns(tick_period); + last_jiffies_update = ktime_add_ns(last_jiffies_update, + incr * ticks); + } else { + last_jiffies_update = ktime_add_ns(last_jiffies_update, + TICK_NSEC); + } - ticks = ktime_divns(delta, incr); + /* Advance jiffies to complete the jiffies_seq protected job */ + jiffies_64 += ticks; - /* Pairs with the lockless read in this function. */ - WRITE_ONCE(last_jiffies_update, - ktime_add_ns(last_jiffies_update, - incr * ticks)); - } - do_timer(++ticks); + /* + * Keep the tick_next_period variable up to date. + */ + nextp = ktime_add_ns(last_jiffies_update, TICK_NSEC); - /* Keep the tick_next_period variable up to date */ - tick_next_period = ktime_add(last_jiffies_update, tick_period); + if (IS_ENABLED(CONFIG_64BIT)) { + /* + * Pairs with smp_load_acquire() in the lockless quick + * check above and ensures that the update to jiffies_64 is + * not reordered vs. the store to tick_next_period, neither + * by the compiler nor by the CPU. + */ + smp_store_release(&tick_next_period, nextp); } else { - write_seqcount_end(&jiffies_seq); - raw_spin_unlock(&jiffies_lock); - return; + /* + * A plain store is good enough on 32bit as the quick check + * above is protected by the sequence count. + */ + tick_next_period = nextp; } + + /* + * Release the sequence count. calc_global_load() below is not + * protected by it, but jiffies_lock needs to be held to prevent + * concurrent invocations. + */ write_seqcount_end(&jiffies_seq); + + calc_global_load(); + raw_spin_unlock(&jiffies_lock); update_wall_time(); } @@ -661,7 +711,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now) hrtimer_set_expires(&ts->sched_timer, ts->last_tick); /* Forward the time to expire in the future */ - hrtimer_forward(&ts->sched_timer, now, tick_period); + hrtimer_forward(&ts->sched_timer, now, TICK_NSEC); if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { hrtimer_start_expires(&ts->sched_timer, @@ -1230,7 +1280,7 @@ static void tick_nohz_handler(struct clock_event_device *dev) if (unlikely(ts->tick_stopped)) return; - hrtimer_forward(&ts->sched_timer, now, tick_period); + hrtimer_forward(&ts->sched_timer, now, TICK_NSEC); tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); } @@ -1267,7 +1317,7 @@ static void tick_nohz_switch_to_nohz(void) next = tick_init_jiffy_update(); hrtimer_set_expires(&ts->sched_timer, next); - hrtimer_forward_now(&ts->sched_timer, tick_period); + hrtimer_forward_now(&ts->sched_timer, TICK_NSEC); tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); tick_nohz_activate(ts, NOHZ_MODE_LOWRES); } @@ -1333,7 +1383,7 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) if (unlikely(ts->tick_stopped)) return HRTIMER_NORESTART; - hrtimer_forward(timer, now, tick_period); + hrtimer_forward(timer, now, TICK_NSEC); return HRTIMER_RESTART; } @@ -1367,13 +1417,13 @@ void tick_setup_sched_timer(void) /* Offset the tick to avert jiffies_lock contention. */ if (sched_skew_tick) { - u64 offset = ktime_to_ns(tick_period) >> 1; + u64 offset = TICK_NSEC >> 1; do_div(offset, num_possible_cpus()); offset *= smp_processor_id(); hrtimer_add_expires_ns(&ts->sched_timer, offset); } - hrtimer_forward(&ts->sched_timer, now, tick_period); + hrtimer_forward(&ts->sched_timer, now, TICK_NSEC); hrtimer_start_expires(&ts->sched_timer, HRTIMER_MODE_ABS_PINNED_HARD); tick_nohz_activate(ts, NOHZ_MODE_HIGHRES); } diff --git a/kernel/time/timeconv.c b/kernel/time/timeconv.c index 589e0a552129..62e3b46717a6 100644 --- a/kernel/time/timeconv.c +++ b/kernel/time/timeconv.c @@ -70,10 +70,10 @@ static const unsigned short __mon_yday[2][13] = { /** * time64_to_tm - converts the calendar time to local broken-down time * - * @totalsecs the number of seconds elapsed since 00:00:00 on January 1, 1970, + * @totalsecs: the number of seconds elapsed since 00:00:00 on January 1, 1970, * Coordinated Universal Time (UTC). - * @offset offset seconds adding to totalsecs. - * @result pointer to struct tm variable to receive broken-down time + * @offset: offset seconds adding to totalsecs. + * @result: pointer to struct tm variable to receive broken-down time */ void time64_to_tm(time64_t totalsecs, int offset, struct tm *result) { diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 6858a31364b6..74503c0151e5 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -407,6 +407,7 @@ static inline u64 timekeeping_cycles_to_ns(const struct tk_read_base *tkr, u64 c /** * update_fast_timekeeper - Update the fast and NMI safe monotonic timekeeper. * @tkr: Timekeeping readout base from which we take the update + * @tkf: Pointer to NMI safe timekeeper * * We want to use this from any context including NMI and tracing / * instrumenting the timekeeping code itself. @@ -436,6 +437,27 @@ static void update_fast_timekeeper(const struct tk_read_base *tkr, memcpy(base + 1, base, sizeof(*base)); } +static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf) +{ + struct tk_read_base *tkr; + unsigned int seq; + u64 now; + + do { + seq = raw_read_seqcount_latch(&tkf->seq); + tkr = tkf->base + (seq & 0x01); + now = ktime_to_ns(tkr->base); + + now += timekeeping_delta_to_ns(tkr, + clocksource_delta( + tk_clock_read(tkr), + tkr->cycle_last, + tkr->mask)); + } while (read_seqcount_latch_retry(&tkf->seq, seq)); + + return now; +} + /** * ktime_get_mono_fast_ns - Fast NMI safe access to clock monotonic * @@ -462,39 +484,24 @@ static void update_fast_timekeeper(const struct tk_read_base *tkr, * * So reader 6 will observe time going backwards versus reader 5. * - * While other CPUs are likely to be able observe that, the only way + * While other CPUs are likely to be able to observe that, the only way * for a CPU local observation is when an NMI hits in the middle of * the update. Timestamps taken from that NMI context might be ahead * of the following timestamps. Callers need to be aware of that and * deal with it. */ -static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf) -{ - struct tk_read_base *tkr; - unsigned int seq; - u64 now; - - do { - seq = raw_read_seqcount_latch(&tkf->seq); - tkr = tkf->base + (seq & 0x01); - now = ktime_to_ns(tkr->base); - - now += timekeeping_delta_to_ns(tkr, - clocksource_delta( - tk_clock_read(tkr), - tkr->cycle_last, - tkr->mask)); - } while (read_seqcount_latch_retry(&tkf->seq, seq)); - - return now; -} - u64 ktime_get_mono_fast_ns(void) { return __ktime_get_fast_ns(&tk_fast_mono); } EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns); +/** + * ktime_get_raw_fast_ns - Fast NMI safe access to clock monotonic raw + * + * Contrary to ktime_get_mono_fast_ns() this is always correct because the + * conversion factor is not affected by NTP/PTP correction. + */ u64 ktime_get_raw_fast_ns(void) { return __ktime_get_fast_ns(&tk_fast_raw); @@ -521,6 +528,9 @@ EXPORT_SYMBOL_GPL(ktime_get_raw_fast_ns); * (2) On 32-bit systems, the 64-bit boot offset (tk->offs_boot) may be * partially updated. Since the tk->offs_boot update is a rare event, this * should be a rare occurrence which postprocessing should be able to handle. + * + * The caveats vs. timestamp ordering as documented for ktime_get_fast_ns() + * apply as well. */ u64 notrace ktime_get_boot_fast_ns(void) { @@ -530,9 +540,6 @@ u64 notrace ktime_get_boot_fast_ns(void) } EXPORT_SYMBOL_GPL(ktime_get_boot_fast_ns); -/* - * See comment for __ktime_get_fast_ns() vs. timestamp ordering - */ static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64 *mono) { struct tk_read_base *tkr; @@ -557,6 +564,8 @@ static __always_inline u64 __ktime_get_real_fast(struct tk_fast *tkf, u64 *mono) /** * ktime_get_real_fast_ns: - NMI safe and fast access to clock realtime. + * + * See ktime_get_fast_ns() for documentation of the time stamp ordering. */ u64 ktime_get_real_fast_ns(void) { @@ -654,6 +663,7 @@ static void update_pvclock_gtod(struct timekeeper *tk, bool was_set) /** * pvclock_gtod_register_notifier - register a pvclock timedata update listener + * @nb: Pointer to the notifier block to register */ int pvclock_gtod_register_notifier(struct notifier_block *nb) { @@ -673,6 +683,7 @@ EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier); /** * pvclock_gtod_unregister_notifier - unregister a pvclock * timedata update listener + * @nb: Pointer to the notifier block to unregister */ int pvclock_gtod_unregister_notifier(struct notifier_block *nb) { @@ -763,6 +774,7 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action) /** * timekeeping_forward_now - update clock to the current time + * @tk: Pointer to the timekeeper to update * * Forward the current clock to update its state since the last call to * update_wall_time(). This is useful before significant clock changes, @@ -1339,7 +1351,7 @@ EXPORT_SYMBOL(do_settimeofday64); /** * timekeeping_inject_offset - Adds or subtracts from the current time. - * @tv: pointer to the timespec variable containing the offset + * @ts: Pointer to the timespec variable containing the offset * * Adds or subtracts an offset value from the current time. */ @@ -1415,9 +1427,8 @@ void timekeeping_warp_clock(void) } } -/** +/* * __timekeeping_set_tai_offset - Sets the TAI offset from UTC and monotonic - * */ static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) { @@ -1425,7 +1436,7 @@ static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tai_offset, 0)); } -/** +/* * change_clocksource - Swaps clocksources if a new one is available * * Accumulates current time interval and initializes new clocksource @@ -1548,6 +1559,7 @@ u64 timekeeping_max_deferment(void) /** * read_persistent_clock64 - Return time from the persistent clock. + * @ts: Pointer to the storage for the readout value * * Weak dummy function for arches that do not yet support it. * Reads the time from the battery backed persistent clock. @@ -1566,8 +1578,9 @@ void __weak read_persistent_clock64(struct timespec64 *ts) * from the boot. * * Weak dummy function for arches that do not yet support it. - * wall_time - current time as returned by persistent clock - * boot_offset - offset that is defined as wall_time - boot_time + * @wall_time: - current time as returned by persistent clock + * @boot_offset: - offset that is defined as wall_time - boot_time + * * The default function calculates offset based on the current value of * local_clock(). This way architectures that support sched_clock() but don't * support dedicated boot time clock will provide the best estimate of the @@ -1652,7 +1665,8 @@ static struct timespec64 timekeeping_suspend_time; /** * __timekeeping_inject_sleeptime - Internal function to add sleep interval - * @delta: pointer to a timespec delta value + * @tk: Pointer to the timekeeper to be updated + * @delta: Pointer to the delta value in timespec64 format * * Takes a timespec offset measuring a suspend interval and properly * adds the sleep offset to the timekeeping variables. @@ -2023,13 +2037,12 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset) } } -/** +/* * accumulate_nsecs_to_secs - Accumulates nsecs into secs * * Helper function that accumulates the nsecs greater than a second * from the xtime_nsec field to the xtime_secs field. * It also calls into the NTP code to handle leapsecond processing. - * */ static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk) { @@ -2071,7 +2084,7 @@ static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk) return clock_set; } -/** +/* * logarithmic_accumulation - shifted accumulation of cycles * * This functions accumulates a shifted interval of cycles into @@ -2314,7 +2327,7 @@ ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real, return base; } -/** +/* * timekeeping_validate_timex - Ensures the timex is ok for use in do_adjtimex */ static int timekeeping_validate_timex(const struct __kernel_timex *txc) diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h index 099737f6f10c..6c2cbd9ef999 100644 --- a/kernel/time/timekeeping.h +++ b/kernel/time/timekeeping.h @@ -26,7 +26,7 @@ extern void do_timer(unsigned long ticks); extern void update_wall_time(void); extern raw_spinlock_t jiffies_lock; -extern seqcount_t jiffies_seq; +extern seqcount_raw_spinlock_t jiffies_seq; #define CS_NAME_LEN 32 diff --git a/kernel/time/timer.c b/kernel/time/timer.c index c3ad64fb9d8b..8dbc008f8942 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1283,7 +1283,7 @@ static void del_timer_wait_running(struct timer_list *timer) u32 tf; tf = READ_ONCE(timer->flags); - if (!(tf & TIMER_MIGRATING)) { + if (!(tf & (TIMER_MIGRATING | TIMER_IRQSAFE))) { struct timer_base *base = get_timer_base(tf); /* @@ -1367,6 +1367,13 @@ int del_timer_sync(struct timer_list *timer) */ WARN_ON(in_irq() && !(timer->flags & TIMER_IRQSAFE)); + /* + * Must be able to sleep on PREEMPT_RT because of the slowpath in + * del_timer_wait_running(). + */ + if (IS_ENABLED(CONFIG_PREEMPT_RT) && !(timer->flags & TIMER_IRQSAFE)) + lockdep_assert_preemption_enabled(); + do { ret = try_to_del_timer_sync(timer); @@ -1693,29 +1700,6 @@ void timer_clear_idle(void) } #endif -/* - * Called from the timer interrupt handler to charge one tick to the current - * process. user_tick is 1 if the tick is user time, 0 for system. - */ -void update_process_times(int user_tick) -{ - struct task_struct *p = current; - - PRANDOM_ADD_NOISE(jiffies, user_tick, p, 0); - - /* Note: this timer irq context must be accounted for as well. */ - account_process_tick(p, user_tick); - run_local_timers(); - rcu_sched_clock_irq(user_tick); -#ifdef CONFIG_IRQ_WORK - if (in_irq()) - irq_work_tick(); -#endif - scheduler_tick(); - if (IS_ENABLED(CONFIG_POSIX_TIMERS)) - run_posix_cpu_timers(); -} - /** * __run_timers - run all expired timers (if any) on this CPU. * @base: the timer vector to be processed. @@ -1765,7 +1749,7 @@ static __latent_entropy void run_timer_softirq(struct softirq_action *h) /* * Called by the local, per-CPU timer interrupt on SMP. */ -void run_local_timers(void) +static void run_local_timers(void) { struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]); @@ -1783,6 +1767,29 @@ void run_local_timers(void) } /* + * Called from the timer interrupt handler to charge one tick to the current + * process. user_tick is 1 if the tick is user time, 0 for system. + */ +void update_process_times(int user_tick) +{ + struct task_struct *p = current; + + PRANDOM_ADD_NOISE(jiffies, user_tick, p, 0); + + /* Note: this timer irq context must be accounted for as well. */ + account_process_tick(p, user_tick); + run_local_timers(); + rcu_sched_clock_irq(user_tick); +#ifdef CONFIG_IRQ_WORK + if (in_irq()) + irq_work_tick(); +#endif + scheduler_tick(); + if (IS_ENABLED(CONFIG_POSIX_TIMERS)) + run_posix_cpu_timers(); +} + +/* * Since schedule_timeout()'s timer is defined on the stack, it must store * the target task on the stack as well. */ diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index acb326f5f50a..6939140ab7c5 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -42,24 +42,11 @@ static void SEQ_printf(struct seq_file *m, const char *fmt, ...) va_end(args); } -static void print_name_offset(struct seq_file *m, void *sym) -{ - char symname[KSYM_NAME_LEN]; - - if (lookup_symbol_name((unsigned long)sym, symname) < 0) - SEQ_printf(m, "<%pK>", sym); - else - SEQ_printf(m, "%s", symname); -} - static void print_timer(struct seq_file *m, struct hrtimer *taddr, struct hrtimer *timer, int idx, u64 now) { - SEQ_printf(m, " #%d: ", idx); - print_name_offset(m, taddr); - SEQ_printf(m, ", "); - print_name_offset(m, timer->function); + SEQ_printf(m, " #%d: <%pK>, %ps", idx, taddr, timer->function); SEQ_printf(m, ", S:%02x", timer->state); SEQ_printf(m, "\n"); SEQ_printf(m, " # expires at %Lu-%Lu nsecs [in %Ld to %Ld nsecs]\n", @@ -116,9 +103,7 @@ print_base(struct seq_file *m, struct hrtimer_clock_base *base, u64 now) SEQ_printf(m, " .resolution: %u nsecs\n", hrtimer_resolution); - SEQ_printf(m, " .get_time: "); - print_name_offset(m, base->get_time); - SEQ_printf(m, "\n"); + SEQ_printf(m, " .get_time: %ps\n", base->get_time); #ifdef CONFIG_HIGH_RES_TIMERS SEQ_printf(m, " .offset: %Lu nsecs\n", (unsigned long long) ktime_to_ns(base->offset)); @@ -218,42 +203,29 @@ print_tickdevice(struct seq_file *m, struct tick_device *td, int cpu) SEQ_printf(m, " next_event: %Ld nsecs\n", (unsigned long long) ktime_to_ns(dev->next_event)); - SEQ_printf(m, " set_next_event: "); - print_name_offset(m, dev->set_next_event); - SEQ_printf(m, "\n"); + SEQ_printf(m, " set_next_event: %ps\n", dev->set_next_event); - if (dev->set_state_shutdown) { - SEQ_printf(m, " shutdown: "); - print_name_offset(m, dev->set_state_shutdown); - SEQ_printf(m, "\n"); - } + if (dev->set_state_shutdown) + SEQ_printf(m, " shutdown: %ps\n", + dev->set_state_shutdown); - if (dev->set_state_periodic) { - SEQ_printf(m, " periodic: "); - print_name_offset(m, dev->set_state_periodic); - SEQ_printf(m, "\n"); - } + if (dev->set_state_periodic) + SEQ_printf(m, " periodic: %ps\n", + dev->set_state_periodic); - if (dev->set_state_oneshot) { - SEQ_printf(m, " oneshot: "); - print_name_offset(m, dev->set_state_oneshot); - SEQ_printf(m, "\n"); - } + if (dev->set_state_oneshot) + SEQ_printf(m, " oneshot: %ps\n", + dev->set_state_oneshot); - if (dev->set_state_oneshot_stopped) { - SEQ_printf(m, " oneshot stopped: "); - print_name_offset(m, dev->set_state_oneshot_stopped); - SEQ_printf(m, "\n"); - } + if (dev->set_state_oneshot_stopped) + SEQ_printf(m, " oneshot stopped: %ps\n", + dev->set_state_oneshot_stopped); - if (dev->tick_resume) { - SEQ_printf(m, " resume: "); - print_name_offset(m, dev->tick_resume); - SEQ_printf(m, "\n"); - } + if (dev->tick_resume) + SEQ_printf(m, " resume: %ps\n", + dev->tick_resume); - SEQ_printf(m, " event_handler: "); - print_name_offset(m, dev->event_handler); + SEQ_printf(m, " event_handler: %ps\n", dev->event_handler); SEQ_printf(m, "\n"); SEQ_printf(m, " retries: %lu\n", dev->retries); SEQ_printf(m, "\n"); |