clocksource/drivers/lpc32xx: Support timer-based ARM delay

This commit implements the ARM timer-based delay timer for the
LPC32xx, LPC18xx, LPC43xx family of SoCs.

Also, add a dependency to restrict compiling this driver for
the ARM architecture.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Joachim Eastwood <manabian@gmail.com>

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 56777f04d2d96381593b4344ac3306bb5dcafbb4..c9c4db6c2797096ec923730c62e2abed526b4b7d 100644 (file)
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -153,6 +153,7 @@ config CLKSRC_EFM32
 config CLKSRC_LPC32XX
        bool "Clocksource for LPC32XX" if COMPILE_TEST
        depends on GENERIC_CLOCKEVENTS && HAS_IOMEM
+       depends on ARM
        select CLKSRC_MMIO
        select CLKSRC_OF
        help

diff --git a/drivers/clocksource/time-lpc32xx.c b/drivers/clocksource/time-lpc32xx.c
index 5694eddade1534a56a0fd9b20f17ecba94375b52..daae61e8c820efd3ca9cef3ef074d2d780e54a8e 100644 (file)
--- a/drivers/clocksource/time-lpc32xx.c
+++ b/drivers/clocksource/time-lpc32xx.c
@@ -18,6 +18,7 @@
 #include <linux/clk.h>
 #include <linux/clockchips.h>
 #include <linux/clocksource.h>
+#include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/kernel.h>
@@ -54,6 +55,15 @@ static u64 notrace lpc32xx_read_sched_clock(void)
        return readl(clocksource_timer_counter);
 }
 
+static unsigned long lpc32xx_delay_timer_read(void)
+{
+       return readl(clocksource_timer_counter);
+}
+
+static struct delay_timer lpc32xx_delay_timer = {
+       .read_current_timer = lpc32xx_delay_timer_read,
+};
+
 static int lpc32xx_clkevt_next_event(unsigned long delta,
                                     struct clock_event_device *evtdev)
 {
@@ -192,6 +202,8 @@ static int __init lpc32xx_clocksource_init(struct device_node *np)
        }
 
        clocksource_timer_counter = base + LPC32XX_TIMER_TC;
+       lpc32xx_delay_timer.freq = rate;
+       register_current_timer_delay(&lpc32xx_delay_timer);
        sched_clock_register(lpc32xx_read_sched_clock, 32, rate);
 
        return 0;