/* * Copyright (C) 2013 Pengutronix * Uwe Kleine-Koenig * * This program is free software; you can redistribute it and/or modify it under * the terms of the GNU General Public License version 2 as published by the * Free Software Foundation. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #define TIMERn_CTRL 0x00 #define TIMERn_CTRL_PRESC(val) (((val) & 0xf) << 24) #define TIMERn_CTRL_PRESC_1024 TIMERn_CTRL_PRESC(10) #define TIMERn_CTRL_CLKSEL(val) (((val) & 0x3) << 16) #define TIMERn_CTRL_CLKSEL_PRESCHFPERCLK TIMERn_CTRL_CLKSEL(0) #define TIMERn_CTRL_OSMEN 0x00000010 #define TIMERn_CTRL_MODE(val) (((val) & 0x3) << 0) #define TIMERn_CTRL_MODE_UP TIMERn_CTRL_MODE(0) #define TIMERn_CTRL_MODE_DOWN TIMERn_CTRL_MODE(1) #define TIMERn_CMD 0x04 #define TIMERn_CMD_START 0x00000001 #define TIMERn_CMD_STOP 0x00000002 #define TIMERn_IEN 0x0c #define TIMERn_IF 0x10 #define TIMERn_IFS 0x14 #define TIMERn_IFC 0x18 #define TIMERn_IRQ_UF 0x00000002 #define TIMERn_TOP 0x1c #define TIMERn_CNT 0x24 struct efm32_clock_event_ddata { struct clock_event_device evtdev; void __iomem *base; unsigned periodic_top; }; static void efm32_clock_event_set_mode(enum clock_event_mode mode, struct clock_event_device *evtdev) { struct efm32_clock_event_ddata *ddata = container_of(evtdev, struct efm32_clock_event_ddata, evtdev); switch (mode) { case CLOCK_EVT_MODE_PERIODIC: writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); writel_relaxed(ddata->periodic_top, ddata->base + TIMERn_TOP); writel_relaxed(TIMERn_CTRL_PRESC_1024 | TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | TIMERn_CTRL_MODE_DOWN, ddata->base + TIMERn_CTRL); writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD); break; case CLOCK_EVT_MODE_ONESHOT: writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); writel_relaxed(TIMERn_CTRL_PRESC_1024 | TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | TIMERn_CTRL_OSMEN | TIMERn_CTRL_MODE_DOWN, ddata->base + TIMERn_CTRL); break; case CLOCK_EVT_MODE_UNUSED: case CLOCK_EVT_MODE_SHUTDOWN: writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); break; case CLOCK_EVT_MODE_RESUME: break; } } static int efm32_clock_event_set_next_event(unsigned long evt, struct clock_event_device *evtdev) { struct efm32_clock_event_ddata *ddata = container_of(evtdev, struct efm32_clock_event_ddata, evtdev); writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD); writel_relaxed(evt, ddata->base + TIMERn_CNT); writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD); return 0; } static irqreturn_t efm32_clock_event_handler(int irq, void *dev_id) { struct efm32_clock_event_ddata *ddata = dev_id; writel_relaxed(TIMERn_IRQ_UF, ddata->base + TIMERn_IFC); ddata->evtdev.event_handler(&ddata->evtdev); return IRQ_HANDLED; } static struct efm32_clock_event_ddata clock_event_ddata = { .evtdev = { .name = "efm32 clockevent", .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_MODE_PERIODIC, .set_mode = efm32_clock_event_set_mode, .set_next_event = efm32_clock_event_set_next_event, .rating = 200, }, }; static struct irqaction efm32_clock_event_irq = { .name = "efm32 clockevent", .flags = IRQF_TIMER, .handler = efm32_clock_event_handler, .dev_id = &clock_event_ddata, }; static int __init efm32_clocksource_init(struct device_node *np) { struct clk *clk; void __iomem *base; unsigned long rate; int ret; clk = of_clk_get(np, 0); if (IS_ERR(clk)) { ret = PTR_ERR(clk); pr_err("failed to get clock for clocksource (%d)\n", ret); goto err_clk_get; } ret = clk_prepare_enable(clk); if (ret) { pr_err("failed to enable timer clock for clocksource (%d)\n", ret); goto err_clk_enable; } rate = clk_get_rate(clk); base = of_iomap(np, 0); if (!base) { ret = -EADDRNOTAVAIL; pr_err("failed to map registers for clocksource\n"); goto err_iomap; } writel_relaxed(TIMERn_CTRL_PRESC_1024 | TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | TIMERn_CTRL_MODE_UP, base + TIMERn_CTRL); writel_relaxed(TIMERn_CMD_START, base + TIMERn_CMD); ret = clocksource_mmio_init(base + TIMERn_CNT, "efm32 timer", DIV_ROUND_CLOSEST(rate, 1024), 200, 16, clocksource_mmio_readl_up); if (ret) { pr_err("failed to init clocksource (%d)\n", ret); goto err_clocksource_init; } return 0; err_clocksource_init: iounmap(base); err_iomap: clk_disable_unprepare(clk); err_clk_enable: clk_put(clk); err_clk_get: return ret; } static int __init efm32_clockevent_init(struct device_node *np) { struct clk *clk; void __iomem *base; unsigned long rate; int irq; int ret; clk = of_clk_get(np, 0); if (IS_ERR(clk)) { ret = PTR_ERR(clk); pr_err("failed to get clock for clockevent (%d)\n", ret); goto err_clk_get; } ret = clk_prepare_enable(clk); if (ret) { pr_err("failed to enable timer clock for clockevent (%d)\n", ret); goto err_clk_enable; } rate = clk_get_rate(clk); base = of_iomap(np, 0); if (!base) { ret = -EADDRNOTAVAIL; pr_err("failed to map registers for clockevent\n"); goto err_iomap; } irq = irq_of_parse_and_map(np, 0); if (!irq) { ret = -ENOENT; pr_err("failed to get irq for clockevent\n"); goto err_get_irq; } writel_relaxed(TIMERn_IRQ_UF, base + TIMERn_IEN); clock_event_ddata.base = base; clock_event_ddata.periodic_top = DIV_ROUND_CLOSEST(rate, 1024 * HZ); setup_irq(irq, &efm32_clock_event_irq); clockevents_config_and_register(&clock_event_ddata.evtdev, DIV_ROUND_CLOSEST(rate, 1024), 0xf, 0xffff); return 0; err_get_irq: iounmap(base); err_iomap: clk_disable_unprepare(clk); err_clk_enable: clk_put(clk); err_clk_get: return ret; } /* * This function asserts that we have exactly one clocksource and one * clock_event_device in the end. */ static void __init efm32_timer_init(struct device_node *np) { static int has_clocksource, has_clockevent; int ret; if (!has_clocksource) { ret = efm32_clocksource_init(np); if (!ret) { has_clocksource = 1; return; } } if (!has_clockevent) { ret = efm32_clockevent_init(np); if (!ret) { has_clockevent = 1; return; } } } CLOCKSOURCE_OF_DECLARE(efm32, "efm32,timer", efm32_timer_init);