This driver handles the TCU (Timer Counter Unit) present on the Ingenic JZ47xx SoCs, and provides the kernel with a system timer, and optionally with a clocksource and a sched_clock. It also provides clocks and interrupt handling to client drivers. Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> --- Notes: v2: Use SPDX identifier for the license v3: - Move documentation to its own patch - Search the devicetree for PWM clients, and use all the TCU channels that won't be used for PWM v4: - Add documentation about why we search for PWM clients - Verify that the PWM clients are for the TCU PWM driver v5: Major overhaul. Too many changes to list. Consider it's a new patch. v6: - Add two API functions ingenic_tcu_request_channel and ingenic_tcu_release_channel. To be used by the PWM driver to request the use of a TCU channel. The driver will now dynamically move away the system timer or clocksource to a new TCU channel. - The system timer now defaults to channel 0, the clocksource now defaults to channel 1 and is no more optional. The ingenic,timer-channel and ingenic,clocksource-channel devicetree properties are now gone. - Fix round_rate / set_rate not calculating the prescale divider the same way. This caused problems when (parent_rate / div) would give a non-integer result. The behaviour is correct now. - The clocksource clock is turned off on suspend now. v7: Fix section mismatch by using builtin_platform_driver_probe() drivers/clocksource/Kconfig | 10 + drivers/clocksource/Makefile | 1 + drivers/clocksource/ingenic-timer.c | 1124 +++++++++++++++++++++++++++++++++++ drivers/clocksource/ingenic-timer.h | 15 + include/linux/mfd/ingenic-tcu.h | 3 + 5 files changed, 1153 insertions(+) create mode 100644 drivers/clocksource/ingenic-timer.c create mode 100644 drivers/clocksource/ingenic-timer.h diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index dec0dd88ec15..98f708208a8d 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -609,4 +609,14 @@ config ATCPIT100_TIMER help This option enables support for the Andestech ATCPIT100 timers. +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 00caf37e52f9..26877505d400 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -75,6 +75,7 @@ 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..c7f529997138 --- /dev/null +++ b/drivers/clocksource/ingenic-timer.c @@ -0,0 +1,1124 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * JZ47xx SoCs TCU IRQ driver + * Copyright (C) 2018 Paul Cercueil <paul@xxxxxxxxxxxxxxx> + */ + +#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/completion.h> +#include <linux/interrupt.h> +#include <linux/irqchip.h> +#include <linux/irqchip/chained_irq.h> +#include <linux/mfd/ingenic-tcu.h> +#include <linux/mutex.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; +}; + +#define to_tcu_clk(_hw) container_of(_hw, struct ingenic_tcu_clk, hw) + +struct ingenic_tcu { + const struct ingenic_soc_info *soc_info; + struct regmap *map; + struct clk *clk, *timer_clk, *clocksource_clk; + + unsigned long requested_channels; + struct mutex channel_request_mutex; + + bool update_timer_channel; + unsigned int new_timer_channel; + struct completion new_timer_switch_job; + int timer_virq; + + struct irq_domain *domain; + unsigned int nb_parent_irqs; + u32 parent_irqs[3]; + + struct clk_hw_onecell_data *clocks; + + unsigned int timer_channel, clocksource_channel; + struct clock_event_device cevt; + struct clocksource cs; + char name[4]; +}; + +static struct ingenic_tcu *ingenic_tcu; + +void __iomem *ingenic_tcu_base; +EXPORT_SYMBOL_GPL(ingenic_tcu_base); + +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; + struct regmap *map = tcu_clk->map; + int ret; + + /* + * Our clock provider has the CLK_SET_PARENT_GATE flag set, so we know + * that the clk is in unprepared state. To be able to access TCSR + * we must ungate the clock supply and we gate it again when done. + */ + + regmap_write(map, TCU_REG_TSCR, BIT(info->gate_bit)); + + ret = regmap_update_bits(map, info->tcsr_reg, + TCU_TCSR_PARENT_CLOCK_MASK, BIT(idx)); + WARN_ONCE(ret < 0, "Unable to update TCSR %i", tcu_clk->idx); + + regmap_write(map, TCU_REG_TSSR, BIT(info->gate_bit)); + + 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; + + /* + * Our clock provider has the CLK_SET_RATE_GATE flag set, so we know + * that the clk is in unprepared state. To be able to access TCSR + * we must ungate the clock supply and we gate it again when done. + */ + + regmap_write(map, TCU_REG_TSCR, BIT(info->gate_bit)); + + 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); + + regmap_write(map, TCU_REG_TSSR, BIT(info->gate_bit)); + + 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_GATE | CLK_SET_PARENT_GATE,\ + }, \ + .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->clocksource_channel; + u16 count; + + count = readw(ingenic_tcu_base + TCU_REG_TCNTc(channel)); + + return count; +} + +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; + + if (unlikely(tcu->update_timer_channel)) { + tcu->update_timer_channel = false; + ingenic_tcu_cevt_set_state_shutdown(evt); + + tcu->timer_channel = tcu->new_timer_channel; + complete(&tcu->new_timer_switch_job); + } + + 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_err("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_err("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_err("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_err("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 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; + } + + tcu->timer_virq = irq_create_mapping(tcu->domain, tcu->timer_channel); + if (!tcu->timer_virq) { + err = -EINVAL; + goto err_clk_disable; + } + + snprintf(tcu->name, sizeof(tcu->name), "TCU"); + + err = request_irq(tcu->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(tcu->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->clocksource_channel; + struct clocksource *cs = &tcu->cs; + unsigned long rate; + int err; + + tcu->clocksource_clk = tcu->clocks->hws[channel]->clk; + + err = clk_prepare_enable(tcu->clocksource_clk); + if (err) + return err; + + rate = clk_get_rate(tcu->clocksource_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 = (u64 (*)(struct clocksource *))ingenic_tcu_timer_read; + + err = clocksource_register_hz(cs, rate); + if (err) + goto err_clk_disable; + + sched_clock_register(ingenic_tcu_timer_read, 16, rate); + + return 0; + +err_clk_disable: + clk_disable_unprepare(tcu->clocksource_clk); + return err; +} + +static void __init ingenic_tcu_clocksource_cleanup(struct ingenic_tcu *tcu) +{ + clocksource_unregister(&tcu->cs); + clk_disable_unprepare(tcu->clocksource_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); + struct ingenic_tcu *tcu; + struct resource res; + void __iomem *base; + int ret; + + of_node_clear_flag(np, OF_POPULATED); + + tcu = kzalloc(sizeof(*tcu), GFP_KERNEL); + if (!tcu) + return -ENOMEM; + + init_completion(&tcu->new_timer_switch_job); + mutex_init(&tcu->channel_request_mutex); + + tcu->soc_info = (const struct ingenic_soc_info *)id->data; + ingenic_tcu = tcu; + + base = of_io_request_and_map(np, 0, NULL); + if (IS_ERR(base)) { + ret = PTR_ERR(base); + goto err_free_ingenic_tcu; + } + + 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; + + tcu->timer_channel = 0; + tcu->clocksource_channel = 1; + tcu->requested_channels = BIT(tcu->timer_channel) + | BIT(tcu->clocksource_channel); + + 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; + + 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); + of_address_to_resource(np, 0, &res); + 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_lock(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + + /* + * We lock the channel_request_mutex when suspending and unlock it when + * resuming. This is done so because at some point in the channel switch + * algorithm we have the old and new clocks enabled at the same time. + */ + mutex_lock(&tcu->channel_request_mutex); + + return 0; +} + +static int ingenic_tcu_resume_unlock(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + + mutex_unlock(&tcu->channel_request_mutex); + + return 0; +} + +static int ingenic_tcu_suspend(struct device *dev) +{ + struct ingenic_tcu *tcu = dev_get_drvdata(dev); + + clk_disable(tcu->clocksource_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->clocksource_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 = { + /* We must not start a channel switch when suspending */ + .suspend = ingenic_tcu_suspend_lock, + .resume = ingenic_tcu_resume_unlock, + + /* _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, + }, +}; +builtin_platform_driver_probe(ingenic_tcu_driver, ingenic_tcu_probe); + +static int ingenic_tcu_get_free_channel(struct ingenic_tcu *tcu) +{ + unsigned int i; + + for (i = 0; i < tcu->soc_info->num_channels; i++) { + if (!(tcu->requested_channels & BIT(i))) { + tcu->requested_channels |= BIT(i); + return i; + } + } + + return -EBUSY; +} + +static struct clk *ingenic_tcu_dup_clk(struct ingenic_tcu *tcu, unsigned int ch) +{ + struct clk *old_clk = tcu->timer_clk, + *new_clk = tcu->clocks->hws[ch]->clk; + unsigned long rate; + int ret; + + rate = clk_get_rate(old_clk); + if (!rate) + return ERR_PTR(-EINVAL); + + /* The new channel must run at the same rate */ + ret = clk_set_rate(new_clk, rate); + if (ret) + return ERR_PTR(ret); + + ret = clk_prepare_enable(new_clk); + if (ret) + return ERR_PTR(ret); + + return new_clk; +} + +static int ingenic_tcu_move_timer(struct ingenic_tcu *tcu) +{ + struct clk *new_clk, *old_clk = tcu->timer_clk; + int ret, virq, old_virq = tcu->timer_virq; + unsigned int new_channel; + + ret = ingenic_tcu_get_free_channel(tcu); + if (ret < 0) + return ret; + + new_channel = ret; + + new_clk = ingenic_tcu_dup_clk(tcu, new_channel); + if (IS_ERR(new_clk)) { + ret = PTR_ERR(new_clk); + goto err_free_channel; + } + + /* Disable the timer so that it doesn't count up */ + regmap_write(tcu->map, TCU_REG_TECR, BIT(new_channel)); + + virq = irq_create_mapping(tcu->domain, new_channel); + if (!virq) { + ret = -EINVAL; + goto err_clk_disable; + } + + ret = request_irq(virq, ingenic_tcu_cevt_cb, IRQF_TIMER, + tcu->name, &tcu->cevt); + if (ret) + goto err_irq_dispose_mapping; + + tcu->timer_clk = new_clk; + + /* Do the switch now */ + reinit_completion(&tcu->new_timer_switch_job); + tcu->timer_virq = virq; + tcu->new_timer_channel = new_channel; + tcu->update_timer_channel = true; + wait_for_completion(&tcu->new_timer_switch_job); + + /* The switch is done, it's safe to release the old timer channel now */ + free_irq(old_virq, &tcu->cevt); + irq_dispose_mapping(old_virq); + clk_disable_unprepare(old_clk); + + pr_info("ingenic-timer: Switched system timer to TCU channel %u\n", + new_channel); + return 0; + +err_irq_dispose_mapping: + irq_dispose_mapping(virq); +err_clk_disable: + clk_disable_unprepare(new_clk); +err_free_channel: + tcu->requested_channels &= ~BIT(new_channel); + return ret; +} + +static int ingenic_tcu_move_clocksource(struct ingenic_tcu *tcu) +{ + struct clk *new_clk, *old_clk = tcu->clocksource_clk; + unsigned int new_channel, old_channel = tcu->clocksource_channel; + unsigned long flags; + u16 tcnt; + int ret; + + ret = ingenic_tcu_get_free_channel(tcu); + if (ret < 0) + return ret; + + new_channel = ret; + + new_clk = ingenic_tcu_dup_clk(tcu, new_channel); + if (IS_ERR(new_clk)) { + tcu->requested_channels &= ~BIT(new_channel); + return PTR_ERR(new_clk); + } + + /* Reset counter */ + regmap_write(tcu->map, TCU_REG_TDFRc(new_channel), 0xffff); + + /* + * Sync the two counters. This must run as fast as possible since we + * disable the main timer; so we temporarily disable interrupts and + * bypass the regmap. + */ + local_irq_save(flags); + + tcu->clocksource_channel = new_channel; + tcu->clocksource_clk = new_clk; + + writel(BIT(old_channel) | BIT(new_channel), + ingenic_tcu_base + TCU_REG_TECR); + + tcnt = readw(ingenic_tcu_base + TCU_REG_TCNTc(old_channel)); + writew(tcnt, ingenic_tcu_base + TCU_REG_TCNTc(new_channel)); + + writel(BIT(new_channel), ingenic_tcu_base + TCU_REG_TESR); + local_irq_restore(flags); + + /* The switch is done, it's safe to release the old timer channel now */ + regmap_write(tcu->map, TCU_REG_TECR, BIT(old_channel)); + clk_disable_unprepare(old_clk); + + pr_info("ingenic-timer: Switched clocksource to TCU channel %u\n", + new_channel); + return 0; +} + +static int ingenic_tcu_request(struct ingenic_tcu *tcu, unsigned int channel) +{ + int ret = 0; + + if (channel >= tcu->soc_info->num_channels) + return -EINVAL; + + mutex_lock(&tcu->channel_request_mutex); + + if (tcu->requested_channels & BIT(channel)) { + if (channel == tcu->timer_channel) + ret = ingenic_tcu_move_timer(tcu); + else if (channel == tcu->clocksource_channel) + ret = ingenic_tcu_move_clocksource(tcu); + else + ret = -EBUSY; + } else { + tcu->requested_channels |= BIT(channel); + } + + mutex_unlock(&tcu->channel_request_mutex); + + if (ret) + pr_err("ingenic-timer: Unable to move channel: %i\n", ret); + return ret; +} + +/** + * ingenic_tcu_request_channel() - Request a TCU channel + * @channel: index of the TCU channel to request + * + * Return: 0 on success, or a negative error code on failure. + */ +int ingenic_tcu_request_channel(unsigned int channel) +{ + return ingenic_tcu_request(ingenic_tcu, channel); +} +EXPORT_SYMBOL_GPL(ingenic_tcu_request_channel); + +static int ingenic_tcu_release(struct ingenic_tcu *tcu, unsigned int channel) +{ + if (channel >= tcu->soc_info->num_channels) + return -EINVAL; + + mutex_lock(&tcu->channel_request_mutex); + + tcu->requested_channels &= ~BIT(channel); + + mutex_unlock(&tcu->channel_request_mutex); + return 0; +} + +/** + * ingenic_tcu_release_channel() - Release a TCU channel + * @channel: index of the TCU channel to release + * + * Return: 0 on success, or a negative error code on failure. + */ +int ingenic_tcu_release_channel(unsigned int channel) +{ + return ingenic_tcu_release(ingenic_tcu, channel); +} +EXPORT_SYMBOL_GPL(ingenic_tcu_release_channel); 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 ab16ad283def..869ac4523a4e 100644 --- a/include/linux/mfd/ingenic-tcu.h +++ b/include/linux/mfd/ingenic-tcu.h @@ -53,4 +53,7 @@ #define TCU_REG_TCNTc(c) (TCU_REG_TCNT0 + ((c) * TCU_CHANNEL_STRIDE)) #define TCU_REG_TCSRc(c) (TCU_REG_TCSR0 + ((c) * TCU_CHANNEL_STRIDE)) +int ingenic_tcu_request_channel(unsigned int channel); +int ingenic_tcu_release_channel(unsigned int channel); + #endif /* __LINUX_MFD_INGENIC_TCU_H_ */ -- 2.11.0