clocksource/drivers/timer-of: Remove percpu irq related code

GCC's named address space checks errors out with:

drivers/clocksource/timer-of.c: In function ‘timer_of_irq_exit’:
drivers/clocksource/timer-of.c:29:46: error: passing argument 2 of
‘free_percpu_irq’ from pointer to non-enclosed address space
  29 |                 free_percpu_irq(of_irq->irq, clkevt);
     |                                              ^~~~~~
In file included from drivers/clocksource/timer-of.c:8:
./include/linux/interrupt.h:201:43: note: expected ‘__seg_gs void *’
but argument is of type ‘struct clock_event_device *’
 201 | extern void free_percpu_irq(unsigned int, void __percpu *);
     |                                           ^~~~~~~~~~~~~~~
drivers/clocksource/timer-of.c: In function ‘timer_of_irq_init’:
drivers/clocksource/timer-of.c:74:51: error: passing argument 4 of
‘request_percpu_irq’ from pointer to non-enclosed address space
  74 |                                    np->full_name, clkevt) :
     |                                                   ^~~~~~
./include/linux/interrupt.h:190:56: note: expected ‘__seg_gs void *’
but argument is of type ‘struct clock_event_device *’
 190 |                    const char *devname, void __percpu *percpu_dev_id)

Sparse warns about:

timer-of.c:29:46: warning: incorrect type in argument 2 (different address spaces)
timer-of.c:29:46:    expected void [noderef] __percpu *
timer-of.c:29:46:    got struct clock_event_device *clkevt
timer-of.c:74:51: warning: incorrect type in argument 4 (different address spaces)
timer-of.c:74:51:    expected void [noderef] __percpu *percpu_dev_id
timer-of.c:74:51:    got struct clock_event_device *clkevt

It appears the code is incorrect as reported by Uros Bizjak:

"The referred code is questionable as it tries to reuse
the clkevent pointer once as percpu pointer and once as generic
pointer, which should be avoided."

This change removes the percpu related code as no drivers is using it.

[Daniel: Fixed the description]

Fixes: dc11bae7 ("clocksource/drivers: Add timer-of common init routine")
Reported-by: Uros Bizjak <ubizjak@gmail.com>
Tested-by: Uros Bizjak <ubizjak@gmail.com>
Link: https://lore.kernel.org/r/20240819100335.2394751-1-daniel.lezcano@linaro.orgSigned-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/clocksource/timer-of.c

@@ -25,9 +25,6 @@ static __init void timer_of_irq_exit(struct of_timer_irq *of_irq)
 
 	struct clock_event_device *clkevt = &to->clkevt;
 
-	if (of_irq->percpu)
-		free_percpu_irq(of_irq->irq, clkevt);
-	else
 	free_irq(of_irq->irq, clkevt);
 }
 
@@ -42,9 +39,6 @@ static __init void timer_of_irq_exit(struct of_timer_irq *of_irq)
  * - Get interrupt number by name
  * - Get interrupt number by index
  *
- * When the interrupt is per CPU, 'request_percpu_irq()' is called,
- * otherwise 'request_irq()' is used.
- *
  * Returns 0 on success, < 0 otherwise
  */
 static __init int timer_of_irq_init(struct device_node *np,
@@ -69,10 +63,7 @@ static __init int timer_of_irq_init(struct device_node *np,
 		return -EINVAL;
 	}
 
-	ret = of_irq->percpu ?
-		request_percpu_irq(of_irq->irq, of_irq->handler,
-				   np->full_name, clkevt) :
-		request_irq(of_irq->irq, of_irq->handler,
+	ret = request_irq(of_irq->irq, of_irq->handler,
 			  of_irq->flags ? of_irq->flags : IRQF_TIMER,
 			  np->full_name, clkevt);
 	if (ret) {

drivers/clocksource/timer-of.h

@@ -11,7 +11,6 @@
 struct of_timer_irq {
 	int irq;
 	int index;
-	int percpu;
 	const char *name;
 	unsigned long flags;
 	irq_handler_t handler;