Re: [PATCH v3 3/3] clocksource/drivers/ostm: Use unique device name instead of ostm

[Simon Horman]

On Fri, Aug 16, 2019 at 03:11:29PM +0200, Simon Horman wrote:
> On Wed, Aug 07, 2019 at 10:46:35AM +0200, Geert Uytterhoeven wrote:
> > Currently all OSTM devices are called "ostm", also in kernel messages.
> > 
> > As there can be multiple instances in an SoC, this can confuse the user.
> > Hence construct a unique name from the DT node name, like is done for
> > platform devices.
> > 
> > On RSK+RZA1, the boot log changes like:
> > 
> >     -clocksource: ostm: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 57352151442 ns
> >     +clocksource: ostm fcfec000.timer: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 57352151442 ns
> >      sched_clock: 32 bits at 33MHz, resolution 30ns, wraps every 64440619504ns
> >     -ostm: used for clocksource
> >     -ostm: used for clock events
> >     +ostm fcfec000.timer: used for clocksource
> >     +ostm fcfec400.timer: used for clock events
> > 
> > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

The nit in my previous email notwithstanding

Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>

> > ---
> > v3:
> >   - Make the name format similar to the one used for platform devices,
> >   - Use kasprintf() instead of buffer size guessing,
> >   - Use a real example from rskrza1.
> > 
> > v2 (by Jacopo):
> >   - Use np->full_name.
> > ---
> >  drivers/clocksource/renesas-ostm.c | 45 ++++++++++++++++++++----------
> >  1 file changed, 30 insertions(+), 15 deletions(-)
> > 
> > diff --git a/drivers/clocksource/renesas-ostm.c b/drivers/clocksource/renesas-ostm.c
> > index 1e22e54d7b0df40d..659e3ec7b86714e3 100644
> > --- a/drivers/clocksource/renesas-ostm.c
> > +++ b/drivers/clocksource/renesas-ostm.c
> > @@ -25,6 +25,7 @@
> >   */
> >  
> >  struct ostm_device {
> > +	const char *name;
> >  	void __iomem *base;
> >  	unsigned long ticks_per_jiffy;
> >  	struct clock_event_device ced;
> > @@ -79,9 +80,8 @@ static int __init ostm_init_clksrc(struct ostm_device *ostm, unsigned long rate)
> >  	writeb(CTL_FREERUN, ostm->base + OSTM_CTL);
> >  	writeb(TS, ostm->base + OSTM_TS);
> >  
> > -	return clocksource_mmio_init(ostm->base + OSTM_CNT,
> > -			"ostm", rate,
> > -			300, 32, clocksource_mmio_readl_up);
> > +	return clocksource_mmio_init(ostm->base + OSTM_CNT, ostm->name, rate,
> > +				     300, 32, clocksource_mmio_readl_up);
> >  }
> >  
> >  static u64 notrace ostm_read_sched_clock(void)
> > @@ -161,15 +161,14 @@ static int __init ostm_init_clkevt(struct ostm_device *ostm, unsigned int irq,
> >  	struct clock_event_device *ced = &ostm->ced;
> >  	int ret = -ENXIO;
> >  
> > -	ret = request_irq(irq, ostm_timer_interrupt,
> > -			  IRQF_TIMER | IRQF_IRQPOLL,
> > -			  "ostm", ostm);
> > +	ret = request_irq(irq, ostm_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
> > +			  ostm->name, ostm);
> >  	if (ret) {
> > -		pr_err("ostm: failed to request irq\n");
> > +		pr_err("%s: Failed to request irq\n", ostm->name);
> >  		return ret;
> >  	}
> >  
> > -	ced->name = "ostm";
> > +	ced->name = ostm->name;
> >  	ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC;
> >  	ced->set_state_shutdown = ostm_shutdown;
> >  	ced->set_state_periodic = ostm_set_periodic;
> > @@ -187,6 +186,7 @@ static int __init ostm_init(struct device_node *np)
> >  {
> >  	struct clk *ostm_clk = NULL;
> >  	struct ostm_device *ostm;
> > +	struct resource res;
> >  	unsigned long rate;
> >  	unsigned int irq;
> >  	int ret;
> > @@ -195,22 +195,35 @@ static int __init ostm_init(struct device_node *np)
> >  	if (!ostm)
> >  		return -ENOMEM;
> >  
> > -	ostm->base = of_iomap(np, 0);
> > -	if (!ostm->base) {
> > +	ret = of_address_to_resource(np, 0, &res);
> > +	if (ret) {
> > +		pr_err("ostm: Failed to obtain I/O memory\n");
> > +		goto err_free;
> > +	}
> > +
> > +	ostm->name = kasprintf(GFP_KERNEL, "ostm %llx.%s",
> > +			       (unsigned long long)res.start, np->name);
> 
> I'm not sure, but looking at printk-formats.rst it seems that
> %pa[p] as a format specifier for resource_size_t. If so it may
> allow dropping the cast above.
> 
> > +	if (!ostm->name) {
> >  		ret = -ENOMEM;
> >  		goto err_free;
> >  	}
> >  
> > +	ostm->base = ioremap(res.start, resource_size(&res));
> > +	if (!ostm->base) {
> > +		ret = -ENOMEM;
> > +		goto err_free_name;
> > +	}
> > +
> >  	irq = irq_of_parse_and_map(np, 0);
> >  	if (!irq) {
> > -		pr_err("ostm: Failed to get irq\n");
> > +		pr_err("%s: Failed to get irq\n", ostm->name);
> >  		ret = -EINVAL;
> >  		goto err_unmap;
> >  	}
> >  
> >  	ostm_clk = of_clk_get(np, 0);
> >  	if (IS_ERR(ostm_clk)) {
> > -		pr_err("ostm: Failed to get clock\n");
> > +		pr_err("%s: Failed to get clock\n", ostm->name);
> >  		ostm_clk = NULL;
> >  		ret = PTR_ERR(ostm_clk);
> >  		goto err_unmap;
> > @@ -218,7 +231,7 @@ static int __init ostm_init(struct device_node *np)
> >  
> >  	ret = clk_prepare_enable(ostm_clk);
> >  	if (ret) {
> > -		pr_err("ostm: Failed to enable clock\n");
> > +		pr_err("%s: Failed to enable clock\n", ostm->name);
> >  		goto err_clk_put;
> >  	}
> >  
> > @@ -235,13 +248,13 @@ static int __init ostm_init(struct device_node *np)
> >  			goto err_clk_disable;
> >  
> >  		ostm_init_sched_clock(ostm, rate);
> > -		pr_info("ostm: used for clocksource\n");
> > +		pr_info("%s: used for clocksource\n", ostm->name);
> >  	} else {
> >  		ret = ostm_init_clkevt(ostm, irq, rate);
> >  		if (ret)
> >  			goto err_clk_disable;
> >  
> > -		pr_info("ostm: used for clock events\n");
> > +		pr_info("%s: used for clock events\n", ostm->name);
> >  	}
> >  
> >  	return 0;
> > @@ -252,6 +265,8 @@ static int __init ostm_init(struct device_node *np)
> >  	clk_put(ostm_clk);
> >  err_unmap:
> >  	iounmap(ostm->base);
> > +err_free_name:
> > +	kfree(ostm->name);
> >  err_free:
> >  	kfree(ostm);
> >  	return ret;
> > -- 
> > 2.17.1
> > 
>