^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Integrator/AP timer driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) * Copyright (C) 2000-2003 Deep Blue Solutions Ltd
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (c) 2014, Linaro Limited
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/clk.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/clocksource.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/of_irq.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/of_address.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/of_platform.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/clockchips.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/sched_clock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include "timer-sp.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) static void __iomem * sched_clk_base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) static u64 notrace integrator_read_sched_clock(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) return -readl(sched_clk_base + TIMER_VALUE);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static int __init integrator_clocksource_init(unsigned long inrate,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) void __iomem *base)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) u32 ctrl = TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) unsigned long rate = inrate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) if (rate >= 1500000) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) rate /= 16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) ctrl |= TIMER_CTRL_DIV16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) writel(0xffff, base + TIMER_LOAD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) writel(ctrl, base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) ret = clocksource_mmio_init(base + TIMER_VALUE, "timer2",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) rate, 200, 16, clocksource_mmio_readl_down);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) sched_clk_base = base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) sched_clock_register(integrator_read_sched_clock, 16, rate);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) static unsigned long timer_reload;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) static void __iomem * clkevt_base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * IRQ handler for the timer
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static irqreturn_t integrator_timer_interrupt(int irq, void *dev_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) struct clock_event_device *evt = dev_id;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /* clear the interrupt */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) writel(1, clkevt_base + TIMER_INTCLR);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) evt->event_handler(evt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) return IRQ_HANDLED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static int clkevt_shutdown(struct clock_event_device *evt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) u32 ctrl = readl(clkevt_base + TIMER_CTRL) & ~TIMER_CTRL_ENABLE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /* Disable timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) writel(ctrl, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) static int clkevt_set_oneshot(struct clock_event_device *evt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) u32 ctrl = readl(clkevt_base + TIMER_CTRL) &
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) ~(TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /* Leave the timer disabled, .set_next_event will enable it */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) writel(ctrl, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) static int clkevt_set_periodic(struct clock_event_device *evt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) u32 ctrl = readl(clkevt_base + TIMER_CTRL) & ~TIMER_CTRL_ENABLE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) /* Disable timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) writel(ctrl, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) /* Enable the timer and start the periodic tick */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) writel(timer_reload, clkevt_base + TIMER_LOAD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) writel(ctrl, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) static int clkevt_set_next_event(unsigned long next, struct clock_event_device *evt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) unsigned long ctrl = readl(clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) writel(ctrl & ~TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) writel(next, clkevt_base + TIMER_LOAD);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) static struct clock_event_device integrator_clockevent = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) .name = "timer1",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) .features = CLOCK_EVT_FEAT_PERIODIC |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) CLOCK_EVT_FEAT_ONESHOT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) .set_state_shutdown = clkevt_shutdown,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) .set_state_periodic = clkevt_set_periodic,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) .set_state_oneshot = clkevt_set_oneshot,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) .tick_resume = clkevt_shutdown,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) .set_next_event = clkevt_set_next_event,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) .rating = 300,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) static int integrator_clockevent_init(unsigned long inrate,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) void __iomem *base, int irq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) unsigned long rate = inrate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) unsigned int ctrl = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) clkevt_base = base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) /* Calculate and program a divisor */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) if (rate > 0x100000 * HZ) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) rate /= 256;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) ctrl |= TIMER_CTRL_DIV256;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) } else if (rate > 0x10000 * HZ) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) rate /= 16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) ctrl |= TIMER_CTRL_DIV16;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) timer_reload = rate / HZ;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) writel(ctrl, clkevt_base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) ret = request_irq(irq, integrator_timer_interrupt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) IRQF_TIMER | IRQF_IRQPOLL, "timer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) &integrator_clockevent);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) clockevents_config_and_register(&integrator_clockevent,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) rate,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 0xffffU);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) static int __init integrator_ap_timer_init_of(struct device_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) const char *path;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) void __iomem *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) int irq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) struct clk *clk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) unsigned long rate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) struct device_node *alias_node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) base = of_io_request_and_map(node, 0, "integrator-timer");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) if (IS_ERR(base))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) return PTR_ERR(base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) clk = of_clk_get(node, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) if (IS_ERR(clk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) pr_err("No clock for %pOFn\n", node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) return PTR_ERR(clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) clk_prepare_enable(clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) rate = clk_get_rate(clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) writel(0, base + TIMER_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) err = of_property_read_string(of_aliases,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) "arm,timer-primary", &path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) pr_warn("Failed to read property\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) alias_node = of_find_node_by_path(path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) * The pointer is used as an identifier not as a pointer, we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) * can drop the refcount on the of__node immediately after
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) * getting it.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) of_node_put(alias_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) if (node == alias_node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) /* The primary timer lacks IRQ, use as clocksource */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) return integrator_clocksource_init(rate, base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) err = of_property_read_string(of_aliases,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) "arm,timer-secondary", &path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) pr_warn("Failed to read property\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) alias_node = of_find_node_by_path(path);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) of_node_put(alias_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) if (node == alias_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) /* The secondary timer will drive the clock event */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) irq = irq_of_parse_and_map(node, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) return integrator_clockevent_init(rate, base, irq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) pr_info("Timer @%p unused\n", base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) clk_disable_unprepare(clk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) TIMER_OF_DECLARE(integrator_ap_timer, "arm,integrator-timer",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) integrator_ap_timer_init_of);