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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/clocksource/timer-efm32.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/clocksource/timer-efm32.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-efm32.c b/drivers/clocksource/timer-efm32.c new file mode 100644 index 000000000..441a4b916 --- /dev/null +++ b/drivers/clocksource/timer-efm32.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2013 Pengutronix + * Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/clocksource.h> +#include <linux/clockchips.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/clk.h> + +#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 int efm32_clock_event_shutdown(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); + return 0; +} + +static int efm32_clock_event_set_oneshot(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(TIMERn_CTRL_PRESC_1024 | + TIMERn_CTRL_CLKSEL_PRESCHFPERCLK | + TIMERn_CTRL_OSMEN | + TIMERn_CTRL_MODE_DOWN, + ddata->base + TIMERn_CTRL); + return 0; +} + +static int efm32_clock_event_set_periodic(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(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); + return 0; +} + +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_FEAT_PERIODIC, + .set_state_shutdown = efm32_clock_event_shutdown, + .set_state_periodic = efm32_clock_event_set_periodic, + .set_state_oneshot = efm32_clock_event_set_oneshot, + .set_next_event = efm32_clock_event_set_next_event, + .rating = 200, + }, +}; + +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); + + clockevents_config_and_register(&clock_event_ddata.evtdev, + DIV_ROUND_CLOSEST(rate, 1024), + 0xf, 0xffff); + + ret = request_irq(irq, efm32_clock_event_handler, IRQF_TIMER, + "efm32 clockevent", &clock_event_ddata); + if (ret) { + pr_err("Failed setup irq\n"); + goto err_setup_irq; + } + + return 0; + +err_setup_irq: +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 int __init efm32_timer_init(struct device_node *np) +{ + static int has_clocksource, has_clockevent; + int ret = 0; + + if (!has_clocksource) { + ret = efm32_clocksource_init(np); + if (!ret) { + has_clocksource = 1; + return 0; + } + } + + if (!has_clockevent) { + ret = efm32_clockevent_init(np); + if (!ret) { + has_clockevent = 1; + return 0; + } + } + + return ret; +} +TIMER_OF_DECLARE(efm32compat, "efm32,timer", efm32_timer_init); +TIMER_OF_DECLARE(efm32, "energymicro,efm32-timer", efm32_timer_init); |