From 059ab7b82eecfc23bc58c491d72ee6b424163578 Mon Sep 17 00:00:00 2001 From: Dong Aisheng Date: Tue, 1 Aug 2017 16:40:17 +0800 Subject: clocksource/drivers/imx-tpm: Add imx tpm timer support IMX Timer/PWM Module (TPM) supports both timer and pwm function while this patch only adds the timer support. PWM would be added later. The TPM counter, compare and capture registers are clocked by an asynchronous clock that can remain enabled in low power modes. NOTE: We observed in a very small probability, the bus fabric contention between GPU and A7 may results a few cycles delay of writing CNT registers which may cause the min_delta event got missed, so we need add a ETIME check here in case it happened. Cc: Daniel Lezcano Cc: Arnd Bergmann Cc: Thomas Gleixner Cc: Shawn Guo Cc: Anson Huang Cc: Bai Ping Signed-off-by: Dong Aisheng Signed-off-by: Daniel Lezcano --- drivers/clocksource/Kconfig | 8 ++ drivers/clocksource/Makefile | 1 + drivers/clocksource/timer-imx-tpm.c | 239 ++++++++++++++++++++++++++++++++++++ 3 files changed, 248 insertions(+) create mode 100644 drivers/clocksource/timer-imx-tpm.c (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index fcae5ca6ac92..0a953fc45a0e 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -598,6 +598,14 @@ config CLKSRC_IMX_GPT depends on ARM && CLKDEV_LOOKUP select CLKSRC_MMIO +config CLKSRC_IMX_TPM + bool "Clocksource using i.MX TPM" if COMPILE_TEST + depends on ARM && CLKDEV_LOOKUP && GENERIC_CLOCKEVENTS + select CLKSRC_MMIO + help + Enable this option to use IMX Timer/PWM Module (TPM) timer as + clocksource. + config CLKSRC_ST_LPC bool "Low power clocksource found in the LPC" if COMPILE_TEST select TIMER_OF if OF diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index 6df949402dfc..dbc1ad14515e 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -67,6 +67,7 @@ obj-$(CONFIG_CLKSRC_VERSATILE) += versatile.o obj-$(CONFIG_CLKSRC_MIPS_GIC) += mips-gic-timer.o obj-$(CONFIG_CLKSRC_TANGO_XTAL) += tango_xtal.o obj-$(CONFIG_CLKSRC_IMX_GPT) += timer-imx-gpt.o +obj-$(CONFIG_CLKSRC_IMX_TPM) += timer-imx-tpm.o obj-$(CONFIG_ASM9260_TIMER) += asm9260_timer.o obj-$(CONFIG_H8300_TMR8) += h8300_timer8.o obj-$(CONFIG_H8300_TMR16) += h8300_timer16.o diff --git a/drivers/clocksource/timer-imx-tpm.c b/drivers/clocksource/timer-imx-tpm.c new file mode 100644 index 000000000000..21bffdcb2f20 --- /dev/null +++ b/drivers/clocksource/timer-imx-tpm.c @@ -0,0 +1,239 @@ +/* + * Copyright 2016 Freescale Semiconductor, Inc. + * Copyright 2017 NXP + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define TPM_SC 0x10 +#define TPM_SC_CMOD_INC_PER_CNT (0x1 << 3) +#define TPM_SC_CMOD_DIV_DEFAULT 0x3 +#define TPM_CNT 0x14 +#define TPM_MOD 0x18 +#define TPM_STATUS 0x1c +#define TPM_STATUS_CH0F BIT(0) +#define TPM_C0SC 0x20 +#define TPM_C0SC_CHIE BIT(6) +#define TPM_C0SC_MODE_SHIFT 2 +#define TPM_C0SC_MODE_MASK 0x3c +#define TPM_C0SC_MODE_SW_COMPARE 0x4 +#define TPM_C0V 0x24 + +static void __iomem *timer_base; +static struct clock_event_device clockevent_tpm; + +static inline void tpm_timer_disable(void) +{ + unsigned int val; + + /* channel disable */ + val = readl(timer_base + TPM_C0SC); + val &= ~(TPM_C0SC_MODE_MASK | TPM_C0SC_CHIE); + writel(val, timer_base + TPM_C0SC); +} + +static inline void tpm_timer_enable(void) +{ + unsigned int val; + + /* channel enabled in sw compare mode */ + val = readl(timer_base + TPM_C0SC); + val |= (TPM_C0SC_MODE_SW_COMPARE << TPM_C0SC_MODE_SHIFT) | + TPM_C0SC_CHIE; + writel(val, timer_base + TPM_C0SC); +} + +static inline void tpm_irq_acknowledge(void) +{ + writel(TPM_STATUS_CH0F, timer_base + TPM_STATUS); +} + +static struct delay_timer tpm_delay_timer; + +static inline unsigned long tpm_read_counter(void) +{ + return readl(timer_base + TPM_CNT); +} + +static unsigned long tpm_read_current_timer(void) +{ + return tpm_read_counter(); +} + +static u64 notrace tpm_read_sched_clock(void) +{ + return tpm_read_counter(); +} + +static int __init tpm_clocksource_init(unsigned long rate) +{ + tpm_delay_timer.read_current_timer = &tpm_read_current_timer; + tpm_delay_timer.freq = rate; + register_current_timer_delay(&tpm_delay_timer); + + sched_clock_register(tpm_read_sched_clock, 32, rate); + + return clocksource_mmio_init(timer_base + TPM_CNT, "imx-tpm", + rate, 200, 32, clocksource_mmio_readl_up); +} + +static int tpm_set_next_event(unsigned long delta, + struct clock_event_device *evt) +{ + unsigned long next, now; + + next = tpm_read_counter(); + next += delta; + writel(next, timer_base + TPM_C0V); + now = tpm_read_counter(); + + /* + * NOTE: We observed in a very small probability, the bus fabric + * contention between GPU and A7 may results a few cycles delay + * of writing CNT registers which may cause the min_delta event got + * missed, so we need add a ETIME check here in case it happened. + */ + return (int)((next - now) <= 0) ? -ETIME : 0; +} + +static int tpm_set_state_oneshot(struct clock_event_device *evt) +{ + tpm_timer_enable(); + + return 0; +} + +static int tpm_set_state_shutdown(struct clock_event_device *evt) +{ + tpm_timer_disable(); + + return 0; +} + +static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + + tpm_irq_acknowledge(); + + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static struct clock_event_device clockevent_tpm = { + .name = "i.MX7ULP TPM Timer", + .features = CLOCK_EVT_FEAT_ONESHOT, + .set_state_oneshot = tpm_set_state_oneshot, + .set_next_event = tpm_set_next_event, + .set_state_shutdown = tpm_set_state_shutdown, + .rating = 200, +}; + +static int __init tpm_clockevent_init(unsigned long rate, int irq) +{ + int ret; + + ret = request_irq(irq, tpm_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL, + "i.MX7ULP TPM Timer", &clockevent_tpm); + + clockevent_tpm.cpumask = cpumask_of(0); + clockevent_tpm.irq = irq; + clockevents_config_and_register(&clockevent_tpm, + rate, 300, 0xfffffffe); + + return ret; +} + +static int __init tpm_timer_init(struct device_node *np) +{ + struct clk *ipg, *per; + int irq, ret; + u32 rate; + + timer_base = of_iomap(np, 0); + if (!timer_base) { + pr_err("tpm: failed to get base address\n"); + return -ENXIO; + } + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + pr_err("tpm: failed to get irq\n"); + ret = -ENOENT; + goto err_iomap; + } + + ipg = of_clk_get_by_name(np, "ipg"); + per = of_clk_get_by_name(np, "per"); + if (IS_ERR(ipg) || IS_ERR(per)) { + pr_err("tpm: failed to get igp or per clk\n"); + ret = -ENODEV; + goto err_clk_get; + } + + /* enable clk before accessing registers */ + ret = clk_prepare_enable(ipg); + if (ret) { + pr_err("tpm: ipg clock enable failed (%d)\n", ret); + goto err_clk_get; + } + + ret = clk_prepare_enable(per); + if (ret) { + pr_err("tpm: per clock enable failed (%d)\n", ret); + goto err_per_clk_enable; + } + + /* + * Initialize tpm module to a known state + * 1) Counter disabled + * 2) TPM counter operates in up counting mode + * 3) Timer Overflow Interrupt disabled + * 4) Channel0 disabled + * 5) DMA transfers disabled + */ + writel(0, timer_base + TPM_SC); + writel(0, timer_base + TPM_CNT); + writel(0, timer_base + TPM_C0SC); + + /* increase per cnt, div 8 by default */ + writel(TPM_SC_CMOD_INC_PER_CNT | TPM_SC_CMOD_DIV_DEFAULT, + timer_base + TPM_SC); + + /* set MOD register to maximum for free running mode */ + writel(0xffffffff, timer_base + TPM_MOD); + + rate = clk_get_rate(per) >> 3; + ret = tpm_clocksource_init(rate); + if (ret) + goto err_per_clk_enable; + + ret = tpm_clockevent_init(rate, irq); + if (ret) + goto err_per_clk_enable; + + return 0; + +err_per_clk_enable: + clk_disable_unprepare(ipg); +err_clk_get: + clk_put(per); + clk_put(ipg); +err_iomap: + iounmap(timer_base); + return ret; +} +TIMER_OF_DECLARE(imx7ulp, "fsl,imx7ulp-tpm", tpm_timer_init); -- cgit v1.2.3 From ebbe266509d8a5453f51f77277da65d870125b72 Mon Sep 17 00:00:00 2001 From: Markus Elfring Date: Sun, 27 Aug 2017 21:38:13 +0200 Subject: clocksource/drivers/bcm2835: Remove message for a memory allocation failure The bcm2835_timer_init() function emits an error message in case of a memory allocation failure. This is pointless as the mm core does that already. Remove this message. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring Signed-off-by: Daniel Lezcano --- drivers/clocksource/bcm2835_timer.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/bcm2835_timer.c b/drivers/clocksource/bcm2835_timer.c index 82828d3a4739..39e489a96ad7 100644 --- a/drivers/clocksource/bcm2835_timer.c +++ b/drivers/clocksource/bcm2835_timer.c @@ -114,7 +114,6 @@ static int __init bcm2835_timer_init(struct device_node *node) timer = kzalloc(sizeof(*timer), GFP_KERNEL); if (!timer) { - pr_err("Can't allocate timer struct\n"); ret = -ENOMEM; goto err_iounmap; } -- cgit v1.2.3 From 469869d18a886e046161ca65516bd3ffcd2f804b Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Tue, 18 Jul 2017 16:42:53 -0500 Subject: clocksource: Convert to using %pOF instead of full_name Now that we have a custom printf format specifier, convert users of full_name to use %pOF instead. This is preparation to remove storing of the full path string for each node. Signed-off-by: Rob Herring Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: Marc Gonzalez Cc: Maxime Coquelin Cc: Alexandre Torgue Cc: linux-arm-kernel@lists.infradead.org Acked-by: Marc Gonzalez Acked-by: Alexandre TORGUE Signed-off-by: Daniel Lezcano --- drivers/clocksource/tango_xtal.c | 6 +++--- drivers/clocksource/timer-of.c | 11 +++++------ drivers/clocksource/timer-probe.c | 3 +-- drivers/clocksource/timer-stm32.c | 8 ++++---- 4 files changed, 13 insertions(+), 15 deletions(-) (limited to 'drivers/clocksource') diff --git a/drivers/clocksource/tango_xtal.c b/drivers/clocksource/tango_xtal.c index c4e1c2e6046f..6a8d9838ce33 100644 --- a/drivers/clocksource/tango_xtal.c +++ b/drivers/clocksource/tango_xtal.c @@ -26,13 +26,13 @@ static int __init tango_clocksource_init(struct device_node *np) xtal_in_cnt = of_iomap(np, 0); if (xtal_in_cnt == NULL) { - pr_err("%s: invalid address\n", np->full_name); + pr_err("%pOF: invalid address\n", np); return -ENXIO; } clk = of_clk_get(np, 0); if (IS_ERR(clk)) { - pr_err("%s: invalid clock\n", np->full_name); + pr_err("%pOF: invalid clock\n", np); return PTR_ERR(clk); } @@ -43,7 +43,7 @@ static int __init tango_clocksource_init(struct device_node *np) ret = clocksource_mmio_init(xtal_in_cnt, "tango-xtal", xtal_freq, 350, 32, clocksource_mmio_readl_up); if (ret) { - pr_err("%s: registration failed\n", np->full_name); + pr_err("%pOF: registration failed\n", np); return ret; } diff --git a/drivers/clocksource/timer-of.c b/drivers/clocksource/timer-of.c index d509b500a7b5..64e00dd41e6f 100644 --- a/drivers/clocksource/timer-of.c +++ b/drivers/clocksource/timer-of.c @@ -52,7 +52,7 @@ static __init int timer_irq_init(struct device_node *np, of_irq->irq = irq_of_parse_and_map(np, of_irq->index); } if (!of_irq->irq) { - pr_err("Failed to map interrupt for %s\n", np->full_name); + pr_err("Failed to map interrupt for %pOF\n", np); return -EINVAL; } @@ -63,8 +63,7 @@ static __init int timer_irq_init(struct device_node *np, of_irq->flags ? of_irq->flags : IRQF_TIMER, np->full_name, clkevt); if (ret) { - pr_err("Failed to request irq %d for %s\n", of_irq->irq, - np->full_name); + pr_err("Failed to request irq %d for %pOF\n", of_irq->irq, np); return ret; } @@ -88,20 +87,20 @@ static __init int timer_clk_init(struct device_node *np, of_clk->clk = of_clk->name ? of_clk_get_by_name(np, of_clk->name) : of_clk_get(np, of_clk->index); if (IS_ERR(of_clk->clk)) { - pr_err("Failed to get clock for %s\n", np->full_name); + pr_err("Failed to get clock for %pOF\n", np); return PTR_ERR(of_clk->clk); } ret = clk_prepare_enable(of_clk->clk); if (ret) { - pr_err("Failed for enable clock for %s\n", np->full_name); + pr_err("Failed for enable clock for %pOF\n", np); goto out_clk_put; } of_clk->rate = clk_get_rate(of_clk->clk); if (!of_clk->rate) { ret = -EINVAL; - pr_err("Failed to get clock rate for %s\n", np->full_name); + pr_err("Failed to get clock rate for %pOF\n", np); goto out_clk_disable; } diff --git a/drivers/clocksource/timer-probe.c b/drivers/clocksource/timer-probe.c index da81e5de74fe..028075720334 100644 --- a/drivers/clocksource/timer-probe.c +++ b/drivers/clocksource/timer-probe.c @@ -40,8 +40,7 @@ void __init timer_probe(void) ret = init_func_ret(np); if (ret) { - pr_err("Failed to initialize '%s': %d\n", - of_node_full_name(np), ret); + pr_err("Failed to initialize '%pOF': %d\n", np, ret); continue; } diff --git a/drivers/clocksource/timer-stm32.c b/drivers/clocksource/timer-stm32.c index 174d1243ea93..8f2423789ba9 100644 --- a/drivers/clocksource/timer-stm32.c +++ b/drivers/clocksource/timer-stm32.c @@ -138,7 +138,7 @@ static int __init stm32_clockevent_init(struct device_node *np) irq = irq_of_parse_and_map(np, 0); if (!irq) { ret = -EINVAL; - pr_err("%s: failed to get irq.\n", np->full_name); + pr_err("%pOF: failed to get irq.\n", np); goto err_get_irq; } @@ -168,12 +168,12 @@ static int __init stm32_clockevent_init(struct device_node *np) ret = request_irq(irq, stm32_clock_event_handler, IRQF_TIMER, "stm32 clockevent", data); if (ret) { - pr_err("%s: failed to request irq.\n", np->full_name); + pr_err("%pOF: failed to request irq.\n", np); goto err_get_irq; } - pr_info("%s: STM32 clockevent driver initialized (%d bits)\n", - np->full_name, bits); + pr_info("%pOF: STM32 clockevent driver initialized (%d bits)\n", + np, bits); return ret; -- cgit v1.2.3