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linux/drivers/clocksource/timer-of.c
Daniel Lezcano 471ef0b5a8 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: dc11bae785 ("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.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2024-09-02 10:04:15 +02:00

222 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2017, Linaro Ltd. All rights reserved.
*
* Author: Daniel Lezcano <daniel.lezcano@linaro.org>
*/
#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/slab.h>
#include "timer-of.h"
/**
* timer_of_irq_exit - Release the interrupt
* @of_irq: an of_timer_irq structure pointer
*
* Free the irq resource
*/
static __init void timer_of_irq_exit(struct of_timer_irq *of_irq)
{
struct timer_of *to = container_of(of_irq, struct timer_of, of_irq);
struct clock_event_device *clkevt = &to->clkevt;
free_irq(of_irq->irq, clkevt);
}
/**
* timer_of_irq_init - Request the interrupt
* @np: a device tree node pointer
* @of_irq: an of_timer_irq structure pointer
*
* Get the interrupt number from the DT from its definition and
* request it. The interrupt is gotten by falling back the following way:
*
* - Get interrupt number by name
* - Get interrupt number by index
*
* Returns 0 on success, < 0 otherwise
*/
static __init int timer_of_irq_init(struct device_node *np,
struct of_timer_irq *of_irq)
{
int ret;
struct timer_of *to = container_of(of_irq, struct timer_of, of_irq);
struct clock_event_device *clkevt = &to->clkevt;
if (of_irq->name) {
of_irq->irq = ret = of_irq_get_byname(np, of_irq->name);
if (ret < 0) {
pr_err("Failed to get interrupt %s for %pOF\n",
of_irq->name, np);
return ret;
}
} else {
of_irq->irq = irq_of_parse_and_map(np, of_irq->index);
}
if (!of_irq->irq) {
pr_err("Failed to map interrupt for %pOF\n", np);
return -EINVAL;
}
ret = request_irq(of_irq->irq, of_irq->handler,
of_irq->flags ? of_irq->flags : IRQF_TIMER,
np->full_name, clkevt);
if (ret) {
pr_err("Failed to request irq %d for %pOF\n", of_irq->irq, np);
return ret;
}
clkevt->irq = of_irq->irq;
return 0;
}
/**
* timer_of_clk_exit - Release the clock resources
* @of_clk: a of_timer_clk structure pointer
*
* Disables and releases the refcount on the clk
*/
static __init void timer_of_clk_exit(struct of_timer_clk *of_clk)
{
of_clk->rate = 0;
clk_disable_unprepare(of_clk->clk);
clk_put(of_clk->clk);
}
/**
* timer_of_clk_init - Initialize the clock resources
* @np: a device tree node pointer
* @of_clk: a of_timer_clk structure pointer
*
* Get the clock by name or by index, enable it and get the rate
*
* Returns 0 on success, < 0 otherwise
*/
static __init int timer_of_clk_init(struct device_node *np,
struct of_timer_clk *of_clk)
{
int ret;
of_clk->clk = of_clk->name ? of_clk_get_by_name(np, of_clk->name) :
of_clk_get(np, of_clk->index);
if (IS_ERR(of_clk->clk)) {
ret = PTR_ERR(of_clk->clk);
if (ret != -EPROBE_DEFER)
pr_err("Failed to get clock for %pOF\n", np);
goto out;
}
ret = clk_prepare_enable(of_clk->clk);
if (ret) {
pr_err("Failed for enable clock for %pOF\n", np);
goto out_clk_put;
}
of_clk->rate = clk_get_rate(of_clk->clk);
if (!of_clk->rate) {
ret = -EINVAL;
pr_err("Failed to get clock rate for %pOF\n", np);
goto out_clk_disable;
}
of_clk->period = DIV_ROUND_UP(of_clk->rate, HZ);
out:
return ret;
out_clk_disable:
clk_disable_unprepare(of_clk->clk);
out_clk_put:
clk_put(of_clk->clk);
goto out;
}
static __init void timer_of_base_exit(struct of_timer_base *of_base)
{
iounmap(of_base->base);
}
static __init int timer_of_base_init(struct device_node *np,
struct of_timer_base *of_base)
{
of_base->base = of_base->name ?
of_io_request_and_map(np, of_base->index, of_base->name) :
of_iomap(np, of_base->index);
if (IS_ERR_OR_NULL(of_base->base)) {
pr_err("Failed to iomap (%s:%s)\n", np->name, of_base->name);
return of_base->base ? PTR_ERR(of_base->base) : -ENOMEM;
}
return 0;
}
int __init timer_of_init(struct device_node *np, struct timer_of *to)
{
int ret = -EINVAL;
int flags = 0;
if (to->flags & TIMER_OF_BASE) {
ret = timer_of_base_init(np, &to->of_base);
if (ret)
goto out_fail;
flags |= TIMER_OF_BASE;
}
if (to->flags & TIMER_OF_CLOCK) {
ret = timer_of_clk_init(np, &to->of_clk);
if (ret)
goto out_fail;
flags |= TIMER_OF_CLOCK;
}
if (to->flags & TIMER_OF_IRQ) {
ret = timer_of_irq_init(np, &to->of_irq);
if (ret)
goto out_fail;
flags |= TIMER_OF_IRQ;
}
if (!to->clkevt.name)
to->clkevt.name = np->full_name;
to->np = np;
return ret;
out_fail:
if (flags & TIMER_OF_IRQ)
timer_of_irq_exit(&to->of_irq);
if (flags & TIMER_OF_CLOCK)
timer_of_clk_exit(&to->of_clk);
if (flags & TIMER_OF_BASE)
timer_of_base_exit(&to->of_base);
return ret;
}
/**
* timer_of_cleanup - release timer_of resources
* @to: timer_of structure
*
* Release the resources that has been used in timer_of_init().
* This function should be called in init error cases
*/
void __init timer_of_cleanup(struct timer_of *to)
{
if (to->flags & TIMER_OF_IRQ)
timer_of_irq_exit(&to->of_irq);
if (to->flags & TIMER_OF_CLOCK)
timer_of_clk_exit(&to->of_clk);
if (to->flags & TIMER_OF_BASE)
timer_of_base_exit(&to->of_base);
}