[v10,04/27] clocksource: Add a new timer-ingenic driver

Message ID	20190302233413.14813-5-paul@crapouillou.net (mailing list archive)
State	Not Applicable
Headers	show Return-Path: <linux-watchdog-owner@kernel.org> From: Paul Cercueil <paul@crapouillou.net> To: Thierry Reding <thierry.reding@gmail.com>, Daniel Lezcano <daniel.lezcano@linaro.org>, Thomas Gleixner <tglx@linutronix.de>, Ralf Baechle <ralf@linux-mips.org>, Paul Burton <paul.burton@mips.com>, James Hogan <jhogan@kernel.org>, Jonathan Corbet <corbet@lwn.net>, =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de> Cc: Mathieu Malaterre <malat@debian.org>, od@zcrc.me, linux-pwm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-mips@vger.kernel.org, linux-doc@vger.kernel.org, linux-clk@vger.kernel.org, Paul Cercueil <paul@crapouillou.net> Subject: [PATCH v10 04/27] clocksource: Add a new timer-ingenic driver Date: Sat, 2 Mar 2019 20:33:50 -0300 Message-Id: <20190302233413.14813-5-paul@crapouillou.net> In-Reply-To: <20190302233413.14813-1-paul@crapouillou.net> References: <20190302233413.14813-1-paul@crapouillou.net> Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk
Series	Ingenic TCU patchset \| expand [5.2,v10,00/27] Ingenic TCU patchset [v10,01/27] dt-bindings: ingenic: Add DT bindings for TCU clocks [v10,02/27] doc: Add doc for the Ingenic TCU hardware [v10,03/27] dt-bindings: Add doc for the Ingenic TCU drivers [v10,04/27] clocksource: Add a new timer-ingenic driver [v10,05/27] clocksource: Add driver for the Ingenic JZ47xx OST [v10,06/27] MAINTAINERS: Add myself as maintainer for Ingenic TCU drivers [v10,07/27] watchdog: jz4740: Use WDT clock provided by TCU driver [v10,08/27] watchdog: jz4740: Use regmap provided by TCU driver [v10,09/27] watchdog: jz4740: Avoid starting watchdog in set_timeout [v10,10/27] watchdog: jz4740: Drop dependency on MACH_JZ47xx, use COMPILE_TEST [v10,11/27] pwm: jz4740: Apply configuration atomically [v10,12/27] pwm: jz4740: Use regmap from TCU driver [v10,13/27] pwm: jz4740: Use clocks from TCU driver [v10,14/27] pwm: jz4740: Improve algorithm of clock calculation [v10,15/27] pwm: jz4740: Allow selection of PWM channels 0 and 1 [v10,16/27] pwm: jz4740: Drop dependency on MACH_INGENIC, use COMPILE_TEST [v10,17/27] pwm: jz4740: Remove unused devicetree compatible strings [v10,18/27] clk: jz4740: Add TCU clock [v10,19/27] MIPS: Kconfig: Select TCU timer driver when MACH_INGENIC is set [v10,20/27] MIPS: jz4740: Add DTS nodes for the TCU drivers [v10,21/27] MIPS: qi_lb60: Move PWM devices to devicetree [v10,22/27] MIPS: qi_lb60: Reduce system timer and clocksource to 750 kHz [v10,23/27] MIPS: CI20: Reduce system timer and clocksource to 3 MHz [v10,24/27] MIPS: CI20: defconfig: enable OST driver [v10,25/27] MIPS: GCW0: Reduce system timer and clocksource to 750 kHz [v10,26/27] MIPS: GCW0: defconfig: Enable OST, watchdog, PWM drivers [v10,27/27] MIPS: jz4740: Drop obsolete code

Hi Thierry, On Mon, Mar 4, 2019 at 1:22 PM, Thierry Reding <thierry.reding@gmail.com> wrote: > On Sat, Mar 02, 2019 at 08:33:50PM -0300, Paul Cercueil wrote: > [...] >> diff --git a/drivers/clocksource/ingenic-timer.c >> b/drivers/clocksource/ingenic-timer.c > [...] >> +struct ingenic_tcu { >> + const struct ingenic_soc_info *soc_info; >> + struct regmap *map; >> + struct clk *clk, *timer_clk, *cs_clk; >> + >> + struct irq_domain *domain; >> + unsigned int nb_parent_irqs; >> + u32 parent_irqs[3]; >> + >> + struct clk_hw_onecell_data *clocks; >> + >> + unsigned int timer_channel, cs_channel; >> + struct clock_event_device cevt; >> + struct clocksource cs; >> + char name[4]; >> + >> + unsigned long pwm_channels_mask; >> +}; >> + >> +static struct ingenic_tcu *ingenic_tcu; > > Is there really a need for this? Seems like the only two reasons for > why > you keep this around are as pointed out below. > >> +void __iomem *ingenic_tcu_base; >> +EXPORT_SYMBOL_GPL(ingenic_tcu_base); > > Same here. > >> +static u64 notrace ingenic_tcu_timer_read(void) >> +{ >> + unsigned int channel = ingenic_tcu->cs_channel; >> + u16 count; >> + >> + count = readw(ingenic_tcu_base + TCU_REG_TCNTc(channel)); > > Can't yo do this via the regmap? I could, but for the sched_clock to be precise the function must return as fast as possible. That's the rationale behind the use of readw() here. That's also the reason why ingenic_tcu_base is global and exported, so that the OS Timer driver can use it as well. >> + >> + return count; >> +} >> + >> +static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource >> *cs) >> +{ >> + return ingenic_tcu_timer_read(); >> +} > > And here you've got access to the struct clocksource *, from which you > should be able to get at struct ingenic_tcu * using container_of. > > [...] >> +static int __init ingenic_tcu_init(struct device_node *np) >> +{ >> + const struct of_device_id *id = >> of_match_node(ingenic_tcu_of_match, np); >> + const struct ingenic_soc_info *soc_info = id->data; >> + struct ingenic_tcu *tcu; >> + struct resource res; >> + void __iomem *base; >> + long rate; >> + int ret; >> + >> + of_node_clear_flag(np, OF_POPULATED); >> + >> + tcu = kzalloc(sizeof(*tcu), GFP_KERNEL); >> + if (!tcu) >> + return -ENOMEM; >> + >> + /* Enable all TCU channels for PWM use by default except channel 0 >> + * and channel 1. >> + */ >> + tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1, 2); >> + of_property_read_u32(np, "ingenic,pwm-channels-mask", >> + (u32 *)&tcu->pwm_channels_mask); >> + >> + /* Verify that we have at least two free channels */ >> + if (hweight8(tcu->pwm_channels_mask) > soc_info->num_channels - >> 2) { >> + pr_crit("ingenic-tcu: Invalid PWM channel mask: 0x%02lx\n", >> + tcu->pwm_channels_mask); >> + return -EINVAL; >> + } >> + >> + tcu->soc_info = soc_info; >> + ingenic_tcu = tcu; >> + >> + tcu->timer_channel = find_first_zero_bit(&tcu->pwm_channels_mask, >> + soc_info->num_channels); >> + tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask, >> + soc_info->num_channels, >> + tcu->timer_channel + 1); >> + >> + base = of_io_request_and_map(np, 0, NULL); >> + if (IS_ERR(base)) { >> + ret = PTR_ERR(base); >> + goto err_free_ingenic_tcu; >> + } >> + >> + of_address_to_resource(np, 0, &res); >> + >> + ingenic_tcu_base = base; >> + >> + tcu->map = regmap_init_mmio(NULL, base, >> &ingenic_tcu_regmap_config); >> + if (IS_ERR(tcu->map)) { >> + ret = PTR_ERR(tcu->map); >> + goto err_iounmap; >> + } >> + >> + tcu->clk = of_clk_get_by_name(np, "tcu"); >> + if (IS_ERR(tcu->clk)) { >> + ret = PTR_ERR(tcu->clk); >> + pr_crit("ingenic-tcu: Unable to find TCU clock: %i\n", ret); >> + goto err_free_regmap; >> + } >> + >> + ret = clk_prepare_enable(tcu->clk); >> + if (ret) { >> + pr_crit("ingenic-tcu: Unable to enable TCU clock: %i\n", ret); >> + goto err_clk_put; >> + } >> + >> + ret = ingenic_tcu_intc_init(tcu, np); >> + if (ret) >> + goto err_clk_disable; >> + >> + ret = ingenic_tcu_clk_init(tcu, np); >> + if (ret) >> + goto err_tcu_intc_cleanup; >> + >> + ret = ingenic_tcu_clocksource_init(tcu); >> + if (ret) >> + goto err_tcu_clk_cleanup; >> + >> + ret = ingenic_tcu_timer_init(tcu); >> + if (ret) >> + goto err_tcu_clocksource_cleanup; >> + >> + // Register the sched_clock at the very end as there's no way to >> undo it >> + rate = clk_get_rate(tcu->cs_clk); >> + sched_clock_register(ingenic_tcu_timer_read, 16, rate); > > Oh wow... so you managed to nicely encapsulate everything and now this > seems to be the only reason why you need to rely on global variables. > > That's unfortunate. I suppose we could go and add a void *data > parameter > to sched_clock_register() and pass that to the read() function. That > way > you could make this completely independent of global variables, but > there are 73 callers of sched_clock_register() and they are spread all > over the place, so sounds a bit daunting to me. Yes, that's the main reason behind the use of a global variables. Is there a way we could introduce another callback, e.g. .read_value(), that would receive a void *param? Then the current .read() callback can be deprecated and the 73 callers can be migrated later. >> + >> + return 0; >> + >> +err_tcu_clocksource_cleanup: >> + ingenic_tcu_clocksource_cleanup(tcu); >> +err_tcu_clk_cleanup: >> + ingenic_tcu_clk_cleanup(tcu, np); >> +err_tcu_intc_cleanup: >> + ingenic_tcu_intc_cleanup(tcu); >> +err_clk_disable: >> + clk_disable_unprepare(tcu->clk); >> +err_clk_put: >> + clk_put(tcu->clk); >> +err_free_regmap: >> + regmap_exit(tcu->map); >> +err_iounmap: >> + iounmap(base); >> + release_mem_region(res.start, resource_size(&res)); >> +err_free_ingenic_tcu: >> + kfree(tcu); >> + return ret; >> +} >> + >> +TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", >> ingenic_tcu_init); >> +TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", >> ingenic_tcu_init); >> +TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", >> ingenic_tcu_init); >> + >> + >> +static int __init ingenic_tcu_probe(struct platform_device *pdev) >> +{ >> + platform_set_drvdata(pdev, ingenic_tcu); > > Then there's also this. Oh well... nevermind then. The content of ingenic_tcu_platform_init() could be moved inside ingenic_tcu_init(). But can we get a hold of the struct device before the probe function is called? That would allow to set the drvdata and regmap without relying on global state. >> +bool ingenic_tcu_pwm_can_use_chn(unsigned int channel) >> +{ >> + return !!(ingenic_tcu->pwm_channels_mask & BIT(channel)); >> +} >> +EXPORT_SYMBOL_GPL(ingenic_tcu_pwm_can_use_chn); > > I wonder if we could make this slightly nicer, though. Judging by the > name, this one seems like it would only ever be used by the PWM. If > the > PWM is a child of the TCU, could it not pass in a struct device * that > points to its parent into this? Or perhaps pass its own struct device > * > and have this function look up the struct ingenic_tcu from that? > Should > be something trivial as: > > bool ingenic_tcu_pwm_can_use_channel(struct device *dev, unsigned > int channel) > { > struct ingenic_tcu *tcu = dev_get_drvdata(dev->parent); > > return !!(tcu->pwm_channels_mask & BIT(channel)); > } > > Thierry Yes, that definitely looks better. Thanks for the hint. -Paul

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index a9e26f6a81a1..d841934e126c 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -634,4 +634,14 @@ config GX6605S_TIMER help This option enables support for gx6605s SOC's timer. +config INGENIC_TIMER + bool "Clocksource/timer using the TCU in Ingenic JZ SoCs" + depends on MIPS || COMPILE_TEST + depends on COMMON_CLK + select TIMER_OF + select IRQ_DOMAIN + select REGMAP + help + Support for the timer/counter unit of the Ingenic JZ SoCs. + endmenu diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index cdd210ff89ea..3eb8c544917f 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_ASM9260_TIMER) += asm9260_timer.o obj-$(CONFIG_H8300_TMR8) += h8300_timer8.o obj-$(CONFIG_H8300_TMR16) += h8300_timer16.o obj-$(CONFIG_H8300_TPU) += h8300_tpu.o +obj-$(CONFIG_INGENIC_TIMER) += ingenic-timer.o obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o obj-$(CONFIG_X86_NUMACHIP) += numachip.o obj-$(CONFIG_ATCPIT100_TIMER) += timer-atcpit100.o diff --git a/drivers/clocksource/ingenic-timer.c b/drivers/clocksource/ingenic-timer.c new file mode 100644 index 000000000000..9529f6389ea4 --- /dev/null +++ b/drivers/clocksource/ingenic-timer.c @@ -0,0 +1,903 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * JZ47xx SoCs TCU IRQ driver + * Copyright (C) 2018 Paul Cercueil <paul@crapouillou.net> + */ + +#include <linux/bitops.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/interrupt.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/mfd/ingenic-tcu.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/sched_clock.h> + +#include <dt-bindings/clock/ingenic,tcu.h> + +#include "ingenic-timer.h" + +/* 8 channels max + watchdog + OST */ +#define TCU_CLK_COUNT 10 + +enum tcu_clk_parent { + TCU_PARENT_PCLK, + TCU_PARENT_RTC, + TCU_PARENT_EXT, +}; + +struct ingenic_soc_info { + unsigned char num_channels; + bool has_ost; +}; + +struct ingenic_tcu_clk_info { + struct clk_init_data init_data; + u8 gate_bit; + u8 tcsr_reg; +}; + +struct ingenic_tcu_clk { + struct clk_hw hw; + + struct regmap *map; + const struct ingenic_tcu_clk_info *info; + + unsigned int idx; +}; + +struct ingenic_tcu { + const struct ingenic_soc_info *soc_info; + struct regmap *map; + struct clk *clk, *timer_clk, *cs_clk; + + struct irq_domain *domain; + unsigned int nb_parent_irqs; + u32 parent_irqs[3]; + + struct clk_hw_onecell_data *clocks; + + unsigned int timer_channel, cs_channel; + struct clock_event_device cevt; + struct clocksource cs; + char name[4]; + + unsigned long pwm_channels_mask; +}; + +static struct ingenic_tcu *ingenic_tcu; + +void __iomem *ingenic_tcu_base; +EXPORT_SYMBOL_GPL(ingenic_tcu_base); + +static inline struct ingenic_tcu_clk *to_tcu_clk(struct clk_hw *hw) +{ + return container_of(hw, struct ingenic_tcu_clk, hw); +} + +static int ingenic_tcu_enable(struct clk_hw *hw) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + + regmap_write(tcu_clk->map, TCU_REG_TSCR, BIT(info->gate_bit)); + + return 0; +} + +static void ingenic_tcu_disable(struct clk_hw *hw) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + + regmap_write(tcu_clk->map, TCU_REG_TSSR, BIT(info->gate_bit)); +} + +static int ingenic_tcu_is_enabled(struct clk_hw *hw) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + unsigned int value; + + regmap_read(tcu_clk->map, TCU_REG_TSR, &value); + + return !(value & BIT(info->gate_bit)); +} + +static u8 ingenic_tcu_get_parent(struct clk_hw *hw) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + unsigned int val = 0; + int ret; + + ret = regmap_read(tcu_clk->map, info->tcsr_reg, &val); + WARN_ONCE(ret < 0, "Unable to read TCSR %i", tcu_clk->idx); + + return ffs(val & TCU_TCSR_PARENT_CLOCK_MASK) - 1; +} + +static int ingenic_tcu_set_parent(struct clk_hw *hw, u8 idx) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + int ret, enabled; + + /* To be able to access TCSR we must ungate the clock supply and we gate + * it again when done. + */ + enabled = ingenic_tcu_is_enabled(hw); + ingenic_tcu_enable(hw); + + ret = regmap_update_bits(tcu_clk->map, info->tcsr_reg, + TCU_TCSR_PARENT_CLOCK_MASK, BIT(idx)); + WARN_ONCE(ret < 0, "Unable to update TCSR %i", tcu_clk->idx); + + if (!enabled) + ingenic_tcu_disable(hw); + + return 0; +} + +static unsigned long ingenic_tcu_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + unsigned int prescale; + int ret; + + ret = regmap_read(tcu_clk->map, info->tcsr_reg, &prescale); + WARN_ONCE(ret < 0, "Unable to read TCSR %i", tcu_clk->idx); + + prescale = (prescale & TCU_TCSR_PRESCALE_MASK) >> TCU_TCSR_PRESCALE_LSB; + + return parent_rate >> (prescale * 2); +} + +static u8 ingenic_tcu_get_prescale(unsigned long rate, unsigned long req_rate) +{ + u8 prescale; + + for (prescale = 0; prescale < 5; prescale++) + if ((rate >> (prescale * 2)) <= req_rate) + return prescale; + + return 5; /* /1024 divider */ +} + +static long ingenic_tcu_round_rate(struct clk_hw *hw, unsigned long req_rate, + unsigned long *parent_rate) +{ + unsigned long rate = *parent_rate; + u8 prescale; + + if (req_rate > rate) + return -EINVAL; + + prescale = ingenic_tcu_get_prescale(rate, req_rate); + + return rate >> (prescale * 2); +} + +static int ingenic_tcu_set_rate(struct clk_hw *hw, unsigned long req_rate, + unsigned long parent_rate) +{ + struct ingenic_tcu_clk *tcu_clk = to_tcu_clk(hw); + const struct ingenic_tcu_clk_info *info = tcu_clk->info; + struct regmap *map = tcu_clk->map; + u8 prescale = ingenic_tcu_get_prescale(parent_rate, req_rate); + int ret; + + ret = regmap_update_bits(map, info->tcsr_reg, + TCU_TCSR_PRESCALE_MASK, + prescale << TCU_TCSR_PRESCALE_LSB); + WARN_ONCE(ret < 0, "Unable to update TCSR %i", tcu_clk->idx); + + return 0; +} + +static const struct clk_ops ingenic_tcu_clk_ops = { + .get_parent = ingenic_tcu_get_parent, + .set_parent = ingenic_tcu_set_parent, + + .recalc_rate = ingenic_tcu_recalc_rate, + .round_rate = ingenic_tcu_round_rate, + .set_rate = ingenic_tcu_set_rate, + + .enable = ingenic_tcu_enable, + .disable = ingenic_tcu_disable, + .is_enabled = ingenic_tcu_is_enabled, +}; + +static const char * const ingenic_tcu_timer_parents[] = { + [TCU_PARENT_PCLK] = "pclk", + [TCU_PARENT_RTC] = "rtc", + [TCU_PARENT_EXT] = "ext", +}; + +#define DEF_TIMER(_name, _gate_bit, _tcsr) \ + { \ + .init_data = { \ + .name = _name, \ + .parent_names = ingenic_tcu_timer_parents, \ + .num_parents = ARRAY_SIZE(ingenic_tcu_timer_parents),\ + .ops = &ingenic_tcu_clk_ops, \ + .flags = CLK_SET_RATE_UNGATE, \ + }, \ + .gate_bit = _gate_bit, \ + .tcsr_reg = _tcsr, \ + } +static const struct ingenic_tcu_clk_info ingenic_tcu_clk_info[] = { + [TCU_CLK_TIMER0] = DEF_TIMER("timer0", 0, TCU_REG_TCSRc(0)), + [TCU_CLK_TIMER1] = DEF_TIMER("timer1", 1, TCU_REG_TCSRc(1)), + [TCU_CLK_TIMER2] = DEF_TIMER("timer2", 2, TCU_REG_TCSRc(2)), + [TCU_CLK_TIMER3] = DEF_TIMER("timer3", 3, TCU_REG_TCSRc(3)), + [TCU_CLK_TIMER4] = DEF_TIMER("timer4", 4, TCU_REG_TCSRc(4)), + [TCU_CLK_TIMER5] = DEF_TIMER("timer5", 5, TCU_REG_TCSRc(5)), + [TCU_CLK_TIMER6] = DEF_TIMER("timer6", 6, TCU_REG_TCSRc(6)), + [TCU_CLK_TIMER7] = DEF_TIMER("timer7", 7, TCU_REG_TCSRc(7)), +}; + +static const struct ingenic_tcu_clk_info ingenic_tcu_watchdog_clk_info = + DEF_TIMER("wdt", 16, TCU_REG_WDT_TCSR); +static const struct ingenic_tcu_clk_info ingenic_tcu_ost_clk_info = + DEF_TIMER("ost", 15, TCU_REG_OST_TCSR); +#undef DEF_TIMER + +static void ingenic_tcu_intc_cascade(struct irq_desc *desc) +{ + struct irq_chip *irq_chip = irq_data_get_irq_chip(&desc->irq_data); + struct irq_domain *domain = irq_desc_get_handler_data(desc); + struct irq_chip_generic *gc = irq_get_domain_generic_chip(domain, 0); + struct regmap *map = gc->private; + uint32_t irq_reg, irq_mask; + unsigned int i; + + regmap_read(map, TCU_REG_TFR, &irq_reg); + regmap_read(map, TCU_REG_TMR, &irq_mask); + + chained_irq_enter(irq_chip, desc); + + irq_reg &= ~irq_mask; + + for_each_set_bit(i, (unsigned long *)&irq_reg, 32) + generic_handle_irq(irq_linear_revmap(domain, i)); + + chained_irq_exit(irq_chip, desc); +} + +static void ingenic_tcu_gc_unmask_enable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = irq_data_get_chip_type(d); + struct regmap *map = gc->private; + u32 mask = d->mask; + + irq_gc_lock(gc); + regmap_write(map, ct->regs.ack, mask); + regmap_write(map, ct->regs.enable, mask); + *ct->mask_cache |= mask; + irq_gc_unlock(gc); +} + +static void ingenic_tcu_gc_mask_disable_reg(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = irq_data_get_chip_type(d); + struct regmap *map = gc->private; + u32 mask = d->mask; + + irq_gc_lock(gc); + regmap_write(map, ct->regs.disable, mask); + *ct->mask_cache &= ~mask; + irq_gc_unlock(gc); +} + +static void ingenic_tcu_gc_mask_disable_reg_and_ack(struct irq_data *d) +{ + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); + struct irq_chip_type *ct = irq_data_get_chip_type(d); + struct regmap *map = gc->private; + u32 mask = d->mask; + + irq_gc_lock(gc); + regmap_write(map, ct->regs.ack, mask); + regmap_write(map, ct->regs.disable, mask); + irq_gc_unlock(gc); +} + +static u64 notrace ingenic_tcu_timer_read(void) +{ + unsigned int channel = ingenic_tcu->cs_channel; + u16 count; + + count = readw(ingenic_tcu_base + TCU_REG_TCNTc(channel)); + + return count; +} + +static u64 notrace ingenic_tcu_timer_cs_read(struct clocksource *cs) +{ + return ingenic_tcu_timer_read(); +} + +static inline struct ingenic_tcu *to_ingenic_tcu(struct clock_event_device *evt) +{ + return container_of(evt, struct ingenic_tcu, cevt); +} + +static int ingenic_tcu_cevt_set_state_shutdown(struct clock_event_device *evt) +{ + struct ingenic_tcu *tcu = to_ingenic_tcu(evt); + + regmap_write(tcu->map, TCU_REG_TECR, BIT(tcu->timer_channel)); + + return 0; +} + +static int ingenic_tcu_cevt_set_next(unsigned long next, + struct clock_event_device *evt) +{ + struct ingenic_tcu *tcu = to_ingenic_tcu(evt); + + if (next > 0xffff) + return -EINVAL; + + regmap_write(tcu->map, TCU_REG_TDFRc(tcu->timer_channel), next); + regmap_write(tcu->map, TCU_REG_TCNTc(tcu->timer_channel), 0); + regmap_write(tcu->map, TCU_REG_TESR, BIT(tcu->timer_channel)); + + return 0; +} + +static irqreturn_t ingenic_tcu_cevt_cb(int irq, void *dev_id) +{ + struct clock_event_device *evt = dev_id; + struct ingenic_tcu *tcu = to_ingenic_tcu(evt); + + regmap_write(tcu->map, TCU_REG_TECR, BIT(tcu->timer_channel)); + + if (evt->event_handler) + evt->event_handler(evt); + + return IRQ_HANDLED; +} + +static int __init ingenic_tcu_register_clock(struct ingenic_tcu *tcu, + unsigned int idx, enum tcu_clk_parent parent, + const struct ingenic_tcu_clk_info *info, + struct clk_hw_onecell_data *clocks) +{ + struct ingenic_tcu_clk *tcu_clk; + int err; + + tcu_clk = kzalloc(sizeof(*tcu_clk), GFP_KERNEL); + if (!tcu_clk) + return -ENOMEM; + + tcu_clk->hw.init = &info->init_data; + tcu_clk->idx = idx; + tcu_clk->info = info; + tcu_clk->map = tcu->map; + + /* Reset channel and clock divider, set default parent */ + ingenic_tcu_enable(&tcu_clk->hw); + regmap_update_bits(tcu->map, info->tcsr_reg, 0xffff, BIT(parent)); + ingenic_tcu_disable(&tcu_clk->hw); + + err = clk_hw_register(NULL, &tcu_clk->hw); + if (err) + goto err_free_tcu_clk; + + err = clk_hw_register_clkdev(&tcu_clk->hw, info->init_data.name, NULL); + if (err) + goto err_clk_unregister; + + clocks->hws[idx] = &tcu_clk->hw; + + return 0; + +err_clk_unregister: + clk_hw_unregister(&tcu_clk->hw); +err_free_tcu_clk: + kfree(tcu_clk); + return err; +} + +static int __init ingenic_tcu_clk_init(struct ingenic_tcu *tcu, + struct device_node *np) +{ + size_t i; + int ret; + + tcu->clocks = kzalloc(sizeof(*tcu->clocks) + + sizeof(*tcu->clocks->hws) * TCU_CLK_COUNT, + GFP_KERNEL); + if (!tcu->clocks) + return -ENOMEM; + + tcu->clocks->num = TCU_CLK_COUNT; + + for (i = 0; i < tcu->soc_info->num_channels; i++) { + ret = ingenic_tcu_register_clock(tcu, i, TCU_PARENT_EXT, + &ingenic_tcu_clk_info[i], + tcu->clocks); + if (ret) { + pr_crit("ingenic-timer: cannot register clock %i\n", i); + goto err_unregister_timer_clocks; + } + } + + /* We set EXT as the default parent clock for all the TCU clocks + * except for the watchdog one, where we set the RTC clock as the + * parent. Since the EXT and PCLK are much faster than the RTC clock, + * the watchdog would kick after a maximum time of 5s, and we might + * want a slower kicking time. + */ + ret = ingenic_tcu_register_clock(tcu, TCU_CLK_WDT, TCU_PARENT_RTC, + &ingenic_tcu_watchdog_clk_info, + tcu->clocks); + if (ret) { + pr_crit("ingenic-timer: cannot register watchdog clock\n"); + goto err_unregister_timer_clocks; + } + + if (tcu->soc_info->has_ost) { + ret = ingenic_tcu_register_clock(tcu, TCU_CLK_OST, + TCU_PARENT_EXT, + &ingenic_tcu_ost_clk_info, + tcu->clocks); + if (ret) { + pr_crit("ingenic-timer: cannot register ost clock\n"); + goto err_unregister_watchdog_clock; + } + } + + ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, tcu->clocks); + if (ret) { + pr_crit("ingenic-timer: cannot add OF clock provider\n"); + goto err_unregister_ost_clock; + } + + return 0; + +err_unregister_ost_clock: + if (tcu->soc_info->has_ost) + clk_hw_unregister(tcu->clocks->hws[i + 1]); +err_unregister_watchdog_clock: + clk_hw_unregister(tcu->clocks->hws[i]); +err_unregister_timer_clocks: + for (i = 0; i < tcu->clocks->num; i++) + if (tcu->clocks->hws[i]) + clk_hw_unregister(tcu->clocks->hws[i]); + kfree(tcu->clocks); + return ret; +} + +static void __init ingenic_tcu_clk_cleanup(struct ingenic_tcu *tcu, + struct device_node *np) +{ + unsigned int i; + + of_clk_del_provider(np); + + for (i = 0; i < tcu->clocks->num; i++) + clk_hw_unregister(tcu->clocks->hws[i]); + kfree(tcu->clocks); +} + +static int __init ingenic_tcu_intc_init(struct ingenic_tcu *tcu, + struct device_node *np) +{ + struct irq_chip_generic *gc; + struct irq_chip_type *ct; + int err, i, irqs; + + irqs = of_property_count_elems_of_size(np, "interrupts", sizeof(u32)); + if (irqs < 0 || irqs > ARRAY_SIZE(tcu->parent_irqs)) + return -EINVAL; + + tcu->nb_parent_irqs = irqs; + + tcu->domain = irq_domain_add_linear(np, 32, &irq_generic_chip_ops, + NULL); + if (!tcu->domain) + return -ENOMEM; + + err = irq_alloc_domain_generic_chips(tcu->domain, 32, 1, "TCU", + handle_level_irq, 0, + IRQ_NOPROBE | IRQ_LEVEL, 0); + if (err) + goto out_domain_remove; + + gc = irq_get_domain_generic_chip(tcu->domain, 0); + ct = gc->chip_types; + + gc->wake_enabled = IRQ_MSK(32); + gc->private = tcu->map; + + ct->regs.disable = TCU_REG_TMSR; + ct->regs.enable = TCU_REG_TMCR; + ct->regs.ack = TCU_REG_TFCR; + ct->chip.irq_unmask = ingenic_tcu_gc_unmask_enable_reg; + ct->chip.irq_mask = ingenic_tcu_gc_mask_disable_reg; + ct->chip.irq_mask_ack = ingenic_tcu_gc_mask_disable_reg_and_ack; + ct->chip.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE; + + /* Mask all IRQs by default */ + regmap_write(tcu->map, TCU_REG_TMSR, IRQ_MSK(32)); + + /* On JZ4740, timer 0 and timer 1 have their own interrupt line; + * timers 2-7 share one interrupt. + * On SoCs >= JZ4770, timer 5 has its own interrupt line; + * timers 0-4 and 6-7 share one single interrupt. + * + * To keep things simple, we just register the same handler to + * all parent interrupts. The handler will properly detect which + * channel fired the interrupt. + */ + for (i = 0; i < irqs; i++) { + tcu->parent_irqs[i] = irq_of_parse_and_map(np, i); + if (!tcu->parent_irqs[i]) { + err = -EINVAL; + goto out_unmap_irqs; + } + + irq_set_chained_handler_and_data(tcu->parent_irqs[i], + ingenic_tcu_intc_cascade, + tcu->domain); + } + + return 0; + +out_unmap_irqs: + for (; i > 0; i--) + irq_dispose_mapping(tcu->parent_irqs[i - 1]); +out_domain_remove: + irq_domain_remove(tcu->domain); + return err; +} + +static void __init ingenic_tcu_intc_cleanup(struct ingenic_tcu *tcu) +{ + unsigned int i; + + for (i = 0; i < tcu->nb_parent_irqs; i++) + irq_dispose_mapping(tcu->parent_irqs[i]); + + irq_domain_remove(tcu->domain); +} + +static int __init ingenic_tcu_timer_init(struct ingenic_tcu *tcu) +{ + unsigned int timer_virq; + unsigned long rate; + int err; + + tcu->timer_clk = tcu->clocks->hws[tcu->timer_channel]->clk; + + err = clk_prepare_enable(tcu->timer_clk); + if (err) + return err; + + rate = clk_get_rate(tcu->timer_clk); + if (!rate) { + err = -EINVAL; + goto err_clk_disable; + } + + timer_virq = irq_create_mapping(tcu->domain, tcu->timer_channel); + if (!timer_virq) { + err = -EINVAL; + goto err_clk_disable; + } + + snprintf(tcu->name, sizeof(tcu->name), "TCU"); + + err = request_irq(timer_virq, ingenic_tcu_cevt_cb, IRQF_TIMER, + tcu->name, &tcu->cevt); + if (err) + goto err_irq_dispose_mapping; + + tcu->cevt.cpumask = cpumask_of(smp_processor_id()); + tcu->cevt.features = CLOCK_EVT_FEAT_ONESHOT; + tcu->cevt.name = tcu->name; + tcu->cevt.rating = 200; + tcu->cevt.set_state_shutdown = ingenic_tcu_cevt_set_state_shutdown; + tcu->cevt.set_next_event = ingenic_tcu_cevt_set_next; + + clockevents_config_and_register(&tcu->cevt, rate, 10, 0xffff); + + return 0; + +err_irq_dispose_mapping: + irq_dispose_mapping(timer_virq); +err_clk_disable: + clk_disable_unprepare(tcu->timer_clk); + return err; +} + +static int __init ingenic_tcu_clocksource_init(struct ingenic_tcu *tcu) +{ + unsigned int channel = tcu->cs_channel; + struct clocksource *cs = &tcu->cs; + unsigned long rate; + int err; + + tcu->cs_clk = tcu->clocks->hws[channel]->clk; + + err = clk_prepare_enable(tcu->cs_clk); + if (err) + return err; + + rate = clk_get_rate(tcu->cs_clk); + if (!rate) { + err = -EINVAL; + goto err_clk_disable; + } + + /* Reset channel */ + regmap_update_bits(tcu->map, TCU_REG_TCSRc(channel), + 0xffff & ~TCU_TCSR_RESERVED_BITS, 0); + + /* Reset counter */ + regmap_write(tcu->map, TCU_REG_TDFRc(channel), 0xffff); + regmap_write(tcu->map, TCU_REG_TCNTc(channel), 0); + + /* Enable channel */ + regmap_write(tcu->map, TCU_REG_TESR, BIT(channel)); + + cs->name = "ingenic-timer"; + cs->rating = 200; + cs->flags = CLOCK_SOURCE_IS_CONTINUOUS; + cs->mask = CLOCKSOURCE_MASK(16); + cs->read = ingenic_tcu_timer_cs_read; + + err = clocksource_register_hz(cs, rate); + if (err) + goto err_clk_disable; + + return 0; + +err_clk_disable: + clk_disable_unprepare(tcu->cs_clk); + return err; +} + +static void __init ingenic_tcu_clocksource_cleanup(struct ingenic_tcu *tcu) +{ + clocksource_unregister(&tcu->cs); + clk_disable_unprepare(tcu->cs_clk); +} + +static const struct regmap_config ingenic_tcu_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +static const struct ingenic_soc_info jz4740_soc_info = { + .num_channels = 8, + .has_ost = false, +}; + +static const struct ingenic_soc_info jz4725b_soc_info = { + .num_channels = 6, + .has_ost = true, +}; + +static const struct ingenic_soc_info jz4770_soc_info = { + .num_channels = 8, + .has_ost = true, +}; + +static const struct of_device_id ingenic_tcu_of_match[] = { + { .compatible = "ingenic,jz4740-tcu", .data = &jz4740_soc_info, }, + { .compatible = "ingenic,jz4725b-tcu", .data = &jz4725b_soc_info, }, + { .compatible = "ingenic,jz4770-tcu", .data = &jz4770_soc_info, }, + { } +}; + +static int __init ingenic_tcu_init(struct device_node *np) +{ + const struct of_device_id *id = of_match_node(ingenic_tcu_of_match, np); + const struct ingenic_soc_info *soc_info = id->data; + struct ingenic_tcu *tcu; + struct resource res; + void __iomem *base; + long rate; + int ret; + + of_node_clear_flag(np, OF_POPULATED); + + tcu = kzalloc(sizeof(*tcu), GFP_KERNEL); + if (!tcu) + return -ENOMEM; + + /* Enable all TCU channels for PWM use by default except channel 0 + * and channel 1. + */ + tcu->pwm_channels_mask = GENMASK(soc_info->num_channels - 1, 2); + of_property_read_u32(np, "ingenic,pwm-channels-mask", + (u32 *)&tcu->pwm_channels_mask); + + /* Verify that we have at least two free channels */ + if (hweight8(tcu->pwm_channels_mask) > soc_info->num_channels - 2) { + pr_crit("ingenic-tcu: Invalid PWM channel mask: 0x%02lx\n", + tcu->pwm_channels_mask); + return -EINVAL; + } + + tcu->soc_info = soc_info; + ingenic_tcu = tcu; + + tcu->timer_channel = find_first_zero_bit(&tcu->pwm_channels_mask, + soc_info->num_channels); + tcu->cs_channel = find_next_zero_bit(&tcu->pwm_channels_mask, + soc_info->num_channels, + tcu->timer_channel + 1); + + base = of_io_request_and_map(np, 0, NULL); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto err_free_ingenic_tcu; + } + + of_address_to_resource(np, 0, &res); + + ingenic_tcu_base = base; + + tcu->map = regmap_init_mmio(NULL, base, &ingenic_tcu_regmap_config); + if (IS_ERR(tcu->map)) { + ret = PTR_ERR(tcu->map); + goto err_iounmap; + } + + tcu->clk = of_clk_get_by_name(np, "tcu"); + if (IS_ERR(tcu->clk)) { + ret = PTR_ERR(tcu->clk); + pr_crit("ingenic-tcu: Unable to find TCU clock: %i\n", ret); + goto err_free_regmap; + } + + ret = clk_prepare_enable(tcu->clk); + if (ret) { + pr_crit("ingenic-tcu: Unable to enable TCU clock: %i\n", ret); + goto err_clk_put; + } + + ret = ingenic_tcu_intc_init(tcu, np); + if (ret) + goto err_clk_disable; + + ret = ingenic_tcu_clk_init(tcu, np); + if (ret) + goto err_tcu_intc_cleanup; + + ret = ingenic_tcu_clocksource_init(tcu); + if (ret) + goto err_tcu_clk_cleanup; + + ret = ingenic_tcu_timer_init(tcu); + if (ret) + goto err_tcu_clocksource_cleanup; + + // Register the sched_clock at the very end as there's no way to undo it + rate = clk_get_rate(tcu->cs_clk); + sched_clock_register(ingenic_tcu_timer_read, 16, rate); + + return 0; + +err_tcu_clocksource_cleanup: + ingenic_tcu_clocksource_cleanup(tcu); +err_tcu_clk_cleanup: + ingenic_tcu_clk_cleanup(tcu, np); +err_tcu_intc_cleanup: + ingenic_tcu_intc_cleanup(tcu); +err_clk_disable: + clk_disable_unprepare(tcu->clk); +err_clk_put: + clk_put(tcu->clk); +err_free_regmap: + regmap_exit(tcu->map); +err_iounmap: + iounmap(base); + release_mem_region(res.start, resource_size(&res)); +err_free_ingenic_tcu: + kfree(tcu); + return ret; +} + +TIMER_OF_DECLARE(jz4740_tcu_intc, "ingenic,jz4740-tcu", ingenic_tcu_init); +TIMER_OF_DECLARE(jz4725b_tcu_intc, "ingenic,jz4725b-tcu", ingenic_tcu_init); +TIMER_OF_DECLARE(jz4770_tcu_intc, "ingenic,jz4770-tcu", ingenic_tcu_init); + + +static int __init ingenic_tcu_probe(struct platform_device *pdev) +{ + platform_set_drvdata(pdev, ingenic_tcu); + + regmap_attach_dev(&pdev->dev, ingenic_tcu->map, + &ingenic_tcu_regmap_config); + + return devm_of_platform_populate(&pdev->dev); +} + +#ifdef CONFIG_PM_SLEEP +static int ingenic_tcu_suspend(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + + clk_disable(tcu->cs_clk); + clk_disable(tcu->timer_clk); + clk_disable(tcu->clk); + return 0; +} + +static int ingenic_tcu_resume(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + int ret; + + ret = clk_enable(tcu->clk); + if (ret) + return ret; + + ret = clk_enable(tcu->timer_clk); + if (ret) + goto err_tcu_clk_disable; + + ret = clk_enable(tcu->cs_clk); + if (ret) + goto err_tcu_timer_clk_disable; + + return 0; + +err_tcu_timer_clk_disable: + clk_disable(tcu->timer_clk); +err_tcu_clk_disable: + clk_disable(tcu->clk); + return ret; +} + +static const struct dev_pm_ops ingenic_tcu_pm_ops = { + /* _noirq: We want the TCU clock to be gated last / ungated first */ + .suspend_noirq = ingenic_tcu_suspend, + .resume_noirq = ingenic_tcu_resume, +}; +#define INGENIC_TCU_PM_OPS (&ingenic_tcu_pm_ops) + +#else +#define INGENIC_TCU_PM_OPS NULL +#endif /* CONFIG_PM_SUSPEND */ + +static struct platform_driver ingenic_tcu_driver = { + .driver = { + .name = "ingenic-tcu", + .pm = INGENIC_TCU_PM_OPS, + .of_match_table = ingenic_tcu_of_match, + }, +}; + +static int __init ingenic_tcu_platform_init(void) +{ + return platform_driver_probe(&ingenic_tcu_driver, + ingenic_tcu_probe); +} +subsys_initcall(ingenic_tcu_platform_init); + +bool ingenic_tcu_pwm_can_use_chn(unsigned int channel) +{ + return !!(ingenic_tcu->pwm_channels_mask & BIT(channel)); +} +EXPORT_SYMBOL_GPL(ingenic_tcu_pwm_can_use_chn); diff --git a/drivers/clocksource/ingenic-timer.h b/drivers/clocksource/ingenic-timer.h new file mode 100644 index 000000000000..fa43da836ab6 --- /dev/null +++ b/drivers/clocksource/ingenic-timer.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __DRIVERS_CLOCKSOURCE_INGENIC_TIMER_H__ +#define __DRIVERS_CLOCKSOURCE_INGENIC_TIMER_H__ + +#include <linux/compiler_types.h> + +/* + * README: For use *ONLY* by the ingenic-ost driver. + * Regular drivers which want to access the TCU registers + * must have ingenic-timer as parent and retrieve the regmap + * doing dev_get_regmap(pdev->dev.parent); + */ +extern void __iomem *ingenic_tcu_base; + +#endif /* __DRIVERS_CLOCKSOURCE_INGENIC_TIMER_H__ */ diff --git a/include/linux/mfd/ingenic-tcu.h b/include/linux/mfd/ingenic-tcu.h index 2083fa20821d..c10b36f3ad64 100644 --- a/include/linux/mfd/ingenic-tcu.h +++ b/include/linux/mfd/ingenic-tcu.h @@ -53,4 +53,6 @@ #define TCU_REG_TCNTc(c) (TCU_REG_TCNT0 + ((c) * TCU_CHANNEL_STRIDE)) #define TCU_REG_TCSRc(c) (TCU_REG_TCSR0 + ((c) * TCU_CHANNEL_STRIDE)) +bool ingenic_tcu_pwm_can_use_chn(unsigned int channel); + #endif /* __LINUX_MFD_INGENIC_TCU_H_ */

[v10,04/27] clocksource: Add a new timer-ingenic driver

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