[PATCH 2/3] clocksource: add device-tree support for PXA timer
From: Daniel Lezcano <hidden>
Date: 2014-07-03 12:05:35
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On 06/22/2014 12:09 AM, Robert Jarzmik wrote:
quoted hunk ↗ jump to hunk
Add device-tree support to PXA platforms. Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr> --- drivers/clocksource/pxa_timer.c | 131 ++++++++++++++++++++++++++++++---------- 1 file changed, 98 insertions(+), 33 deletions(-)diff --git a/drivers/clocksource/pxa_timer.c b/drivers/clocksource/pxa_timer.c index fca174e..67da3f5 100644 --- a/drivers/clocksource/pxa_timer.c +++ b/drivers/clocksource/pxa_timer.c@@ -15,14 +15,41 @@ #include <linux/kernel.h> #include <linux/init.h> #include <linux/interrupt.h> +#include <linux/clk.h> #include <linux/clockchips.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <linux/sched_clock.h> #include <asm/div64.h> #include <asm/mach/irq.h> #include <asm/mach/time.h> -#include <mach/regs-ost.h> #include <mach/irqs.h> +#include <mach/hardware.h>
Now as the driver is in 'drivers', do not reference the headers files in mach. Moving the driver to the drivers directory implies some cleanup with the headers dependencies.
+#define OSMR0 0x00 /* */ +#define OSMR1 0x04 /* */ +#define OSMR2 0x08 /* */ +#define OSMR3 0x0C /* */ +#define OSMR4 0x80 /* */
Can you please remove those unused empty comment or fill them with something appropriate.
+#define OSCR 0x10 /* OS Timer Counter Register */ +#define OSCR4 0x40 /* OS Timer Counter Register */ +#define OMCR4 0xC0 /* */ +#define OSSR 0x14 /* OS Timer Status Register */ +#define OWER 0x18 /* OS Timer Watchdog Enable Register */ +#define OIER 0x1C /* OS Timer Interrupt Enable Register */ + +#define OSSR_M3 (1 << 3) /* Match status channel 3 */ +#define OSSR_M2 (1 << 2) /* Match status channel 2 */ +#define OSSR_M1 (1 << 1) /* Match status channel 1 */ +#define OSSR_M0 (1 << 0) /* Match status channel 0 */ + +#define OWER_WME (1 << 0) /* Watchdog Match Enable */ + +#define OIER_E3 (1 << 3) /* Interrupt enable channel 3 */ +#define OIER_E2 (1 << 2) /* Interrupt enable channel 2 */ +#define OIER_E1 (1 << 1) /* Interrupt enable channel 1 */ +#define OIER_E0 (1 << 0) /* Interrupt enable channel 0 */
Is it possible to do some cleanups around regs-ost.h and here in order to remove the unused macros. Also, it seems some define will be duplicate as they are shared with the watchdog. Any plan to fix that ?
quoted hunk ↗ jump to hunk
/* * This is PXA's sched_clock implementation. This has a resolution@@ -33,9 +60,14 @@ * calls to sched_clock() which should always be the case in practice. */ +#define timer_readl(reg) readl_relaxed(timer_base + (reg)) +#define timer_writel(val, reg) writel_relaxed((val), timer_base + (reg)) + +static void __iomem *timer_base; + static u64 notrace pxa_read_sched_clock(void) { - return readl_relaxed(OSCR);
So here there is a change which is not explained in the changelog (timer_base offset). Even it is obvious for me because I am used to see this kind of code, that would deserve a better description in the changelog.
+ return timer_readl(OSCR); }
[ ... ]
+static void __init pxa_timer_dt_init(struct device_node *np)
+{
+ struct clk *clk;
+ int irq;
+
+ /* timer registers are shared with watchdog timer */
+ timer_base = of_iomap(np, 0);
+ if (!timer_base)
+ panic("%s: unable to map resource\n", np->name);
+
+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk))
+ panic("%s: unable to get clk\n", np->name);
+ clk_prepare_enable(clk);
+
+ /* we are only interested in OS-timer0 irq */
+ irq = irq_of_parse_and_map(np, 0);
+ if (irq <= 0)
+ panic("%s: unable to parse OS-timer0 irq\n", np->name);Is the 'panic' desirable ? The clksrc-of is written in a way to use different clocks, no ?
+
+ pxa_timer_common_init(irq, clk_get_rate(clk));
+}
+CLOCKSOURCE_OF_DECLARE(pxa_timer, "marvell,pxa-timer", pxa_timer_dt_init);
+
+/*
+ * Legacy timer init for non device-tree boards.
+ */
+void __init pxa_timer_init(void)
+{
+ unsigned long clock_tick_rate = get_clock_tick_rate();
+
+ timer_base = io_p2v(0x40a00000);
+ pxa_timer_common_init(IRQ_OST0, clock_tick_rate);
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