// SPDX-License-Identifier: GPL-2.0 /* * Ingenic XBurst SoCs SYSOST clocks driver * Copyright (c) 2020 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com> */ #include <linux/bitfield.h> #include <linux/bitops.h> #include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/clockchips.h> #include <linux/clocksource.h> #include <linux/interrupt.h> #include <linux/mfd/syscon.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/sched_clock.h> #include <linux/slab.h> #include <linux/syscore_ops.h> #include <dt-bindings/clock/ingenic,sysost.h> /* OST register offsets */ #define OST_REG_OSTCCR 0x00 #define OST_REG_OSTCR 0x08 #define OST_REG_OSTFR 0x0c #define OST_REG_OSTMR 0x10 #define OST_REG_OST1DFR 0x14 #define OST_REG_OST1CNT 0x18 #define OST_REG_OST2CNTL 0x20 #define OST_REG_OSTCNT2HBUF 0x24 #define OST_REG_OSTESR 0x34 #define OST_REG_OSTECR 0x38 /* bits within the OSTCCR register */ #define OSTCCR_PRESCALE1_MASK 0x3 #define OSTCCR_PRESCALE2_MASK 0xc /* bits within the OSTCR register */ #define OSTCR_OST1CLR BIT(0) #define OSTCR_OST2CLR BIT(1) /* bits within the OSTFR register */ #define OSTFR_FFLAG BIT(0) /* bits within the OSTMR register */ #define OSTMR_FMASK BIT(0) /* bits within the OSTESR register */ #define OSTESR_OST1ENS BIT(0) #define OSTESR_OST2ENS BIT(1) /* bits within the OSTECR register */ #define OSTECR_OST1ENC BIT(0) #define OSTECR_OST2ENC BIT(1) struct ingenic_soc_info { unsigned int num_channels; }; struct ingenic_ost_clk_info { struct clk_init_data init_data; u8 ostccr_reg; }; struct ingenic_ost_clk { struct clk_hw hw; unsigned int idx; struct ingenic_ost *ost; const struct ingenic_ost_clk_info *info; }; struct ingenic_ost { void __iomem *base; const struct ingenic_soc_info *soc_info; struct clk *clk, *percpu_timer_clk, *global_timer_clk; struct clock_event_device cevt; struct clocksource cs; char name[20]; struct clk_hw_onecell_data *clocks; }; static struct ingenic_ost *ingenic_ost; static inline struct ingenic_ost_clk *to_ost_clk(struct clk_hw *hw) { return container_of(hw, struct ingenic_ost_clk, hw); } static unsigned long ingenic_ost_percpu_timer_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct ingenic_ost_clk *ost_clk = to_ost_clk(hw); const struct ingenic_ost_clk_info *info = ost_clk->info; unsigned int prescale; prescale = readl(ost_clk->ost->base + info->ostccr_reg); prescale = FIELD_GET(OSTCCR_PRESCALE1_MASK, prescale); return parent_rate >> (prescale * 2); } static unsigned long ingenic_ost_global_timer_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct ingenic_ost_clk *ost_clk = to_ost_clk(hw); const struct ingenic_ost_clk_info *info = ost_clk->info; unsigned int prescale; prescale = readl(ost_clk->ost->base + info->ostccr_reg); prescale = FIELD_GET(OSTCCR_PRESCALE2_MASK, prescale); return parent_rate >> (prescale * 2); } static u8 ingenic_ost_get_prescale(unsigned long rate, unsigned long req_rate) { u8 prescale; for (prescale = 0; prescale < 2; prescale++) if ((rate >> (prescale * 2)) <= req_rate) return prescale; return 2; /* /16 divider */ } static long ingenic_ost_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 rate; prescale = ingenic_ost_get_prescale(rate, req_rate); return rate >> (prescale * 2); } static int ingenic_ost_percpu_timer_set_rate(struct clk_hw *hw, unsigned long req_rate, unsigned long parent_rate) { struct ingenic_ost_clk *ost_clk = to_ost_clk(hw); const struct ingenic_ost_clk_info *info = ost_clk->info; u8 prescale = ingenic_ost_get_prescale(parent_rate, req_rate); int val; val = readl(ost_clk->ost->base + info->ostccr_reg); val &= ~OSTCCR_PRESCALE1_MASK; val |= FIELD_PREP(OSTCCR_PRESCALE1_MASK, prescale); writel(val, ost_clk->ost->base + info->ostccr_reg); return 0; } static int ingenic_ost_global_timer_set_rate(struct clk_hw *hw, unsigned long req_rate, unsigned long parent_rate) { struct ingenic_ost_clk *ost_clk = to_ost_clk(hw); const struct ingenic_ost_clk_info *info = ost_clk->info; u8 prescale = ingenic_ost_get_prescale(parent_rate, req_rate); int val; val = readl(ost_clk->ost->base + info->ostccr_reg); val &= ~OSTCCR_PRESCALE2_MASK; val |= FIELD_PREP(OSTCCR_PRESCALE2_MASK, prescale); writel(val, ost_clk->ost->base + info->ostccr_reg); return 0; } static const struct clk_ops ingenic_ost_percpu_timer_ops = { .recalc_rate = ingenic_ost_percpu_timer_recalc_rate, .round_rate = ingenic_ost_round_rate, .set_rate = ingenic_ost_percpu_timer_set_rate, }; static const struct clk_ops ingenic_ost_global_timer_ops = { .recalc_rate = ingenic_ost_global_timer_recalc_rate, .round_rate = ingenic_ost_round_rate, .set_rate = ingenic_ost_global_timer_set_rate, }; static const char * const ingenic_ost_clk_parents[] = { "ext" }; static const struct ingenic_ost_clk_info x1000_ost_clk_info[] = { [OST_CLK_PERCPU_TIMER] = { .init_data = { .name = "percpu timer", .parent_names = ingenic_ost_clk_parents, .num_parents = ARRAY_SIZE(ingenic_ost_clk_parents), .ops = &ingenic_ost_percpu_timer_ops, .flags = CLK_SET_RATE_UNGATE, }, .ostccr_reg = OST_REG_OSTCCR, }, [OST_CLK_GLOBAL_TIMER] = { .init_data = { .name = "global timer", .parent_names = ingenic_ost_clk_parents, .num_parents = ARRAY_SIZE(ingenic_ost_clk_parents), .ops = &ingenic_ost_global_timer_ops, .flags = CLK_SET_RATE_UNGATE, }, .ostccr_reg = OST_REG_OSTCCR, }, }; static u64 notrace ingenic_ost_global_timer_read_cntl(void) { struct ingenic_ost *ost = ingenic_ost; unsigned int count; count = readl(ost->base + OST_REG_OST2CNTL); return count; } static u64 notrace ingenic_ost_clocksource_read(struct clocksource *cs) { return ingenic_ost_global_timer_read_cntl(); } static inline struct ingenic_ost *to_ingenic_ost(struct clock_event_device *evt) { return container_of(evt, struct ingenic_ost, cevt); } static int ingenic_ost_cevt_set_state_shutdown(struct clock_event_device *evt) { struct ingenic_ost *ost = to_ingenic_ost(evt); writel(OSTECR_OST1ENC, ost->base + OST_REG_OSTECR); return 0; } static int ingenic_ost_cevt_set_next(unsigned long next, struct clock_event_device *evt) { struct ingenic_ost *ost = to_ingenic_ost(evt); writel((u32)~OSTFR_FFLAG, ost->base + OST_REG_OSTFR); writel(next, ost->base + OST_REG_OST1DFR); writel(OSTCR_OST1CLR, ost->base + OST_REG_OSTCR); writel(OSTESR_OST1ENS, ost->base + OST_REG_OSTESR); writel((u32)~OSTMR_FMASK, ost->base + OST_REG_OSTMR); return 0; } static irqreturn_t ingenic_ost_cevt_cb(int irq, void *dev_id) { struct clock_event_device *evt = dev_id; struct ingenic_ost *ost = to_ingenic_ost(evt); writel(OSTECR_OST1ENC, ost->base + OST_REG_OSTECR); if (evt->event_handler) evt->event_handler(evt); return IRQ_HANDLED; } static int __init ingenic_ost_register_clock(struct ingenic_ost *ost, unsigned int idx, const struct ingenic_ost_clk_info *info, struct clk_hw_onecell_data *clocks) { struct ingenic_ost_clk *ost_clk; int val, err; ost_clk = kzalloc(sizeof(*ost_clk), GFP_KERNEL); if (!ost_clk) return -ENOMEM; ost_clk->hw.init = &info->init_data; ost_clk->idx = idx; ost_clk->info = info; ost_clk->ost = ost; /* Reset clock divider */ val = readl(ost->base + info->ostccr_reg); val &= ~(OSTCCR_PRESCALE1_MASK | OSTCCR_PRESCALE2_MASK); writel(val, ost->base + info->ostccr_reg); err = clk_hw_register(NULL, &ost_clk->hw); if (err) { kfree(ost_clk); return err; } clocks->hws[idx] = &ost_clk->hw; return 0; } static struct clk * __init ingenic_ost_get_clock(struct device_node *np, int id) { struct of_phandle_args args; args.np = np; args.args_count = 1; args.args[0] = id; return of_clk_get_from_provider(&args); } static int __init ingenic_ost_percpu_timer_init(struct device_node *np, struct ingenic_ost *ost) { unsigned int timer_virq, channel = OST_CLK_PERCPU_TIMER; unsigned long rate; int err; ost->percpu_timer_clk = ingenic_ost_get_clock(np, channel); if (IS_ERR(ost->percpu_timer_clk)) return PTR_ERR(ost->percpu_timer_clk); err = clk_prepare_enable(ost->percpu_timer_clk); if (err) goto err_clk_put; rate = clk_get_rate(ost->percpu_timer_clk); if (!rate) { err = -EINVAL; goto err_clk_disable; } timer_virq = of_irq_get(np, 0); if (!timer_virq) { err = -EINVAL; goto err_clk_disable; } snprintf(ost->name, sizeof(ost->name), "OST percpu timer"); err = request_irq(timer_virq, ingenic_ost_cevt_cb, IRQF_TIMER, ost->name, &ost->cevt); if (err) goto err_irq_dispose_mapping; ost->cevt.cpumask = cpumask_of(smp_processor_id()); ost->cevt.features = CLOCK_EVT_FEAT_ONESHOT; ost->cevt.name = ost->name; ost->cevt.rating = 400; ost->cevt.set_state_shutdown = ingenic_ost_cevt_set_state_shutdown; ost->cevt.set_next_event = ingenic_ost_cevt_set_next; clockevents_config_and_register(&ost->cevt, rate, 4, 0xffffffff); return 0; err_irq_dispose_mapping: irq_dispose_mapping(timer_virq); err_clk_disable: clk_disable_unprepare(ost->percpu_timer_clk); err_clk_put: clk_put(ost->percpu_timer_clk); return err; } static int __init ingenic_ost_global_timer_init(struct device_node *np, struct ingenic_ost *ost) { unsigned int channel = OST_CLK_GLOBAL_TIMER; struct clocksource *cs = &ost->cs; unsigned long rate; int err; ost->global_timer_clk = ingenic_ost_get_clock(np, channel); if (IS_ERR(ost->global_timer_clk)) return PTR_ERR(ost->global_timer_clk); err = clk_prepare_enable(ost->global_timer_clk); if (err) goto err_clk_put; rate = clk_get_rate(ost->global_timer_clk); if (!rate) { err = -EINVAL; goto err_clk_disable; } /* Clear counter CNT registers */ writel(OSTCR_OST2CLR, ost->base + OST_REG_OSTCR); /* Enable OST channel */ writel(OSTESR_OST2ENS, ost->base + OST_REG_OSTESR); cs->name = "ingenic-ost"; cs->rating = 400; cs->flags = CLOCK_SOURCE_IS_CONTINUOUS; cs->mask = CLOCKSOURCE_MASK(32); cs->read = ingenic_ost_clocksource_read; err = clocksource_register_hz(cs, rate); if (err) goto err_clk_disable; return 0; err_clk_disable: clk_disable_unprepare(ost->global_timer_clk); err_clk_put: clk_put(ost->global_timer_clk); return err; } static const struct ingenic_soc_info x1000_soc_info = { .num_channels = 2, }; static const struct of_device_id __maybe_unused ingenic_ost_of_matches[] __initconst = { { .compatible = "ingenic,x1000-ost", .data = &x1000_soc_info }, { /* sentinel */ } }; static int __init ingenic_ost_probe(struct device_node *np) { const struct of_device_id *id = of_match_node(ingenic_ost_of_matches, np); struct ingenic_ost *ost; unsigned int i; int ret; ost = kzalloc(sizeof(*ost), GFP_KERNEL); if (!ost) return -ENOMEM; ost->base = of_io_request_and_map(np, 0, of_node_full_name(np)); if (IS_ERR(ost->base)) { pr_err("%s: Failed to map OST registers\n", __func__); ret = PTR_ERR(ost->base); goto err_free_ost; } ost->clk = of_clk_get_by_name(np, "ost"); if (IS_ERR(ost->clk)) { ret = PTR_ERR(ost->clk); pr_crit("%s: Cannot get OST clock\n", __func__); goto err_free_ost; } ret = clk_prepare_enable(ost->clk); if (ret) { pr_crit("%s: Unable to enable OST clock\n", __func__); goto err_put_clk; } ost->soc_info = id->data; ost->clocks = kzalloc(struct_size(ost->clocks, hws, ost->soc_info->num_channels), GFP_KERNEL); if (!ost->clocks) { ret = -ENOMEM; goto err_clk_disable; } ost->clocks->num = ost->soc_info->num_channels; for (i = 0; i < ost->clocks->num; i++) { ret = ingenic_ost_register_clock(ost, i, &x1000_ost_clk_info[i], ost->clocks); if (ret) { pr_crit("%s: Cannot register clock %d\n", __func__, i); goto err_unregister_ost_clocks; } } ret = of_clk_add_hw_provider(np, of_clk_hw_onecell_get, ost->clocks); if (ret) { pr_crit("%s: Cannot add OF clock provider\n", __func__); goto err_unregister_ost_clocks; } ingenic_ost = ost; return 0; err_unregister_ost_clocks: for (i = 0; i < ost->clocks->num; i++) if (ost->clocks->hws[i]) clk_hw_unregister(ost->clocks->hws[i]); kfree(ost->clocks); err_clk_disable: clk_disable_unprepare(ost->clk); err_put_clk: clk_put(ost->clk); err_free_ost: kfree(ost); return ret; } static int __init ingenic_ost_init(struct device_node *np) { struct ingenic_ost *ost; unsigned long rate; int ret; ret = ingenic_ost_probe(np); if (ret) { pr_crit("%s: Failed to initialize OST clocks: %d\n", __func__, ret); return ret; } of_node_clear_flag(np, OF_POPULATED); ost = ingenic_ost; if (IS_ERR(ost)) return PTR_ERR(ost); ret = ingenic_ost_global_timer_init(np, ost); if (ret) { pr_crit("%s: Unable to init global timer: %x\n", __func__, ret); goto err_free_ingenic_ost; } ret = ingenic_ost_percpu_timer_init(np, ost); if (ret) goto err_ost_global_timer_cleanup; /* Register the sched_clock at the end as there's no way to undo it */ rate = clk_get_rate(ost->global_timer_clk); sched_clock_register(ingenic_ost_global_timer_read_cntl, 32, rate); return 0; err_ost_global_timer_cleanup: clocksource_unregister(&ost->cs); clk_disable_unprepare(ost->global_timer_clk); clk_put(ost->global_timer_clk); err_free_ingenic_ost: kfree(ost); return ret; } TIMER_OF_DECLARE(x1000_ost, "ingenic,x1000-ost", ingenic_ost_init);