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![Daniel Lezcano](/assets/img/avatar_default.png)
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the clocksource at early stage. However, this macro is also used to initialize the clockevent if any, or the clockevent only. It was originally suggested to declare another macro to initialize a clockevent, so in order to separate the two entities even they belong to the same IP. This was not accepted because of the impact on the DT where splitting a clocksource/clockevent definition does not make sense as it is a Linux concept not a hardware description. On the other side, the clocksource has not interrupt declared while the clockevent has, so it is easy from the driver to know if the description is for a clockevent or a clocksource, IOW it could be implemented at the driver level. So instead of dealing with a named clocksource macro, let's use a more generic one: TIMER_OF_DECLARE. The patch has not functional changes. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
56 lines
1.3 KiB
C
56 lines
1.3 KiB
C
#include <linux/clocksource.h>
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#include <linux/sched_clock.h>
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#include <linux/of_address.h>
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#include <linux/printk.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/clk.h>
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static void __iomem *xtal_in_cnt;
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static struct delay_timer delay_timer;
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static unsigned long notrace read_xtal_counter(void)
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{
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return readl_relaxed(xtal_in_cnt);
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}
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static u64 notrace read_sched_clock(void)
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{
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return read_xtal_counter();
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}
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static int __init tango_clocksource_init(struct device_node *np)
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{
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struct clk *clk;
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int xtal_freq, ret;
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xtal_in_cnt = of_iomap(np, 0);
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if (xtal_in_cnt == NULL) {
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pr_err("%s: invalid address\n", np->full_name);
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return -ENXIO;
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}
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clk = of_clk_get(np, 0);
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if (IS_ERR(clk)) {
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pr_err("%s: invalid clock\n", np->full_name);
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return PTR_ERR(clk);
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}
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xtal_freq = clk_get_rate(clk);
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delay_timer.freq = xtal_freq;
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delay_timer.read_current_timer = read_xtal_counter;
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ret = clocksource_mmio_init(xtal_in_cnt, "tango-xtal", xtal_freq, 350,
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32, clocksource_mmio_readl_up);
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if (ret) {
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pr_err("%s: registration failed\n", np->full_name);
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return ret;
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}
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sched_clock_register(read_sched_clock, 32, xtal_freq);
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register_current_timer_delay(&delay_timer);
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return 0;
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}
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TIMER_OF_DECLARE(tango, "sigma,tick-counter", tango_clocksource_init);
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