diff mbox series

[05/19] irqchip/mmp: do not use of_address_to_resource() to get mux regs

Message ID 20190809093158.7969-6-lkundrak@v3.sk (mailing list archive)
State New, archived
Headers show
Series Initial support for Marvell MMP3 SoC | expand

Commit Message

Lubomir Rintel Aug. 9, 2019, 9:31 a.m. UTC
The "regs" property of the "mrvl,mmp2-mux-intc" devices are silly. They
are offsets from intc's base, not addresses on the parent bus. At this
point it probably can't be fixed.

On an OLPC XO-1.75 machine, the muxes are children of the intc, not the
axi bus, and thus of_address_to_resource() won't work. We should treat
the values as mere integers as opposed to bus addresses.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>

---
 drivers/irqchip/irq-mmp.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

Comments

Marc Zyngier Aug. 9, 2019, 12:12 p.m. UTC | #1
On 09/08/2019 10:31, Lubomir Rintel wrote:
> The "regs" property of the "mrvl,mmp2-mux-intc" devices are silly. They
> are offsets from intc's base, not addresses on the parent bus. At this
> point it probably can't be fixed.
> 
> On an OLPC XO-1.75 machine, the muxes are children of the intc, not the
> axi bus, and thus of_address_to_resource() won't work. We should treat
> the values as mere integers as opposed to bus addresses.
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> 
> ---
>  drivers/irqchip/irq-mmp.c | 20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
> index 14618dc0bd396..af9cba4a51c2e 100644
> --- a/drivers/irqchip/irq-mmp.c
> +++ b/drivers/irqchip/irq-mmp.c
> @@ -424,9 +424,9 @@ IRQCHIP_DECLARE(mmp2_intc, "mrvl,mmp2-intc", mmp2_of_init);
>  static int __init mmp2_mux_of_init(struct device_node *node,
>  				   struct device_node *parent)
>  {
> -	struct resource res;
>  	int i, ret, irq, j = 0;
>  	u32 nr_irqs, mfp_irq;
> +	u32 reg[4];
>  
>  	if (!parent)
>  		return -ENODEV;
> @@ -438,18 +438,20 @@ static int __init mmp2_mux_of_init(struct device_node *node,
>  		pr_err("Not found mrvl,intc-nr-irqs property\n");
>  		return -EINVAL;
>  	}
> -	ret = of_address_to_resource(node, 0, &res);
> +
> +	/*
> +	 * For historical reasonsm, the "regs" property of the
> +	 * mrvl,mmp2-mux-intc is not a regular * "regs" property containing
> +	 * addresses on the parent bus, but offsets from the intc's base.
> +	 * That is why we can't use of_address_to_resource() here.
> +	 */
> +	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));

This will return 0 even if you've read less than your expected 4 u32s.
You may want to try of_property_read_variable_u32_array instead.

>  	if (ret < 0) {
>  		pr_err("Not found reg property\n");
>  		return -EINVAL;
>  	}
> -	icu_data[i].reg_status = mmp_icu_base + res.start;
> -	ret = of_address_to_resource(node, 1, &res);
> -	if (ret < 0) {
> -		pr_err("Not found reg property\n");
> -		return -EINVAL;
> -	}
> -	icu_data[i].reg_mask = mmp_icu_base + res.start;
> +	icu_data[i].reg_status = mmp_icu_base + reg[0];
> +	icu_data[i].reg_mask = mmp_icu_base + reg[2];
>  	icu_data[i].cascade_irq = irq_of_parse_and_map(node, 0);
>  	if (!icu_data[i].cascade_irq)
>  		return -EINVAL;
> 

Thanks,

	M.
Lubomir Rintel Aug. 16, 2019, 6:41 p.m. UTC | #2
On Fri, 2019-08-09 at 13:12 +0100, Marc Zyngier wrote:
> On 09/08/2019 10:31, Lubomir Rintel wrote:
> > The "regs" property of the "mrvl,mmp2-mux-intc" devices are silly. They
> > are offsets from intc's base, not addresses on the parent bus. At this
> > point it probably can't be fixed.
> > 
> > On an OLPC XO-1.75 machine, the muxes are children of the intc, not the
> > axi bus, and thus of_address_to_resource() won't work. We should treat
> > the values as mere integers as opposed to bus addresses.
> > 
> > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > Acked-by: Pavel Machek <pavel@ucw.cz>
> > 
> > ---
> >  drivers/irqchip/irq-mmp.c | 20 +++++++++++---------
> >  1 file changed, 11 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
> > index 14618dc0bd396..af9cba4a51c2e 100644
> > --- a/drivers/irqchip/irq-mmp.c
> > +++ b/drivers/irqchip/irq-mmp.c
> > @@ -424,9 +424,9 @@ IRQCHIP_DECLARE(mmp2_intc, "mrvl,mmp2-intc", mmp2_of_init);
> >  static int __init mmp2_mux_of_init(struct device_node *node,
> >  				   struct device_node *parent)
> >  {
> > -	struct resource res;
> >  	int i, ret, irq, j = 0;
> >  	u32 nr_irqs, mfp_irq;
> > +	u32 reg[4];
> >  
> >  	if (!parent)
> >  		return -ENODEV;
> > @@ -438,18 +438,20 @@ static int __init mmp2_mux_of_init(struct device_node *node,
> >  		pr_err("Not found mrvl,intc-nr-irqs property\n");
> >  		return -EINVAL;
> >  	}
> > -	ret = of_address_to_resource(node, 0, &res);
> > +
> > +	/*
> > +	 * For historical reasonsm, the "regs" property of the
> > +	 * mrvl,mmp2-mux-intc is not a regular * "regs" property containing
> > +	 * addresses on the parent bus, but offsets from the intc's base.
> > +	 * That is why we can't use of_address_to_resource() here.
> > +	 */
> > +	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
> 
> This will return 0 even if you've read less than your expected 4 u32s.
> You may want to try of_property_read_variable_u32_array instead.

Will it? Unless I'm reading the of_property_read_u32_array()
documentation wrong, it suggests that would return -EOVERFLOW in that
case.

It ignores the extra values it the property is larger. I guess that is
not a good thing and we still want to use
of_property_read_variable_u32_array() though.

> >  	if (ret < 0) {
> >  		pr_err("Not found reg property\n");
> >  		return -EINVAL;
> >  	}
> > -	icu_data[i].reg_status = mmp_icu_base + res.start;
> > -	ret = of_address_to_resource(node, 1, &res);
> > -	if (ret < 0) {
> > -		pr_err("Not found reg property\n");
> > -		return -EINVAL;
> > -	}
> > -	icu_data[i].reg_mask = mmp_icu_base + res.start;
> > +	icu_data[i].reg_status = mmp_icu_base + reg[0];
> > +	icu_data[i].reg_mask = mmp_icu_base + reg[2];
> >  	icu_data[i].cascade_irq = irq_of_parse_and_map(node, 0);
> >  	if (!icu_data[i].cascade_irq)
> >  		return -EINVAL;
> > 
> 
> Thanks,
> 
> 	M.

Thanks
Lubo
Marc Zyngier Aug. 17, 2019, 6:17 p.m. UTC | #3
On Fri, 16 Aug 2019 20:41:22 +0200
Lubomir Rintel <lkundrak@v3.sk> wrote:

> On Fri, 2019-08-09 at 13:12 +0100, Marc Zyngier wrote:
> > On 09/08/2019 10:31, Lubomir Rintel wrote:  
> > > The "regs" property of the "mrvl,mmp2-mux-intc" devices are silly. They
> > > are offsets from intc's base, not addresses on the parent bus. At this
> > > point it probably can't be fixed.
> > > 
> > > On an OLPC XO-1.75 machine, the muxes are children of the intc, not the
> > > axi bus, and thus of_address_to_resource() won't work. We should treat
> > > the values as mere integers as opposed to bus addresses.
> > > 
> > > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > > Acked-by: Pavel Machek <pavel@ucw.cz>
> > > 
> > > ---
> > >  drivers/irqchip/irq-mmp.c | 20 +++++++++++---------
> > >  1 file changed, 11 insertions(+), 9 deletions(-)
> > > 
> > > diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
> > > index 14618dc0bd396..af9cba4a51c2e 100644
> > > --- a/drivers/irqchip/irq-mmp.c
> > > +++ b/drivers/irqchip/irq-mmp.c
> > > @@ -424,9 +424,9 @@ IRQCHIP_DECLARE(mmp2_intc, "mrvl,mmp2-intc", mmp2_of_init);
> > >  static int __init mmp2_mux_of_init(struct device_node *node,
> > >  				   struct device_node *parent)
> > >  {
> > > -	struct resource res;
> > >  	int i, ret, irq, j = 0;
> > >  	u32 nr_irqs, mfp_irq;
> > > +	u32 reg[4];
> > >  
> > >  	if (!parent)
> > >  		return -ENODEV;
> > > @@ -438,18 +438,20 @@ static int __init mmp2_mux_of_init(struct device_node *node,
> > >  		pr_err("Not found mrvl,intc-nr-irqs property\n");
> > >  		return -EINVAL;
> > >  	}
> > > -	ret = of_address_to_resource(node, 0, &res);
> > > +
> > > +	/*
> > > +	 * For historical reasonsm, the "regs" property of the
> > > +	 * mrvl,mmp2-mux-intc is not a regular * "regs" property containing
> > > +	 * addresses on the parent bus, but offsets from the intc's base.
> > > +	 * That is why we can't use of_address_to_resource() here.
> > > +	 */
> > > +	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));  
> > 
> > This will return 0 even if you've read less than your expected 4 u32s.
> > You may want to try of_property_read_variable_u32_array instead.  
> 
> Will it? Unless I'm reading the of_property_read_u32_array()
> documentation wrong, it suggests that would return -EOVERFLOW in that
> case.

You're appear to be right, and I read it wrong.

> 
> It ignores the extra values it the property is larger. I guess that is
> not a good thing and we still want to use
> of_property_read_variable_u32_array() though.

It doesn't hurt to check for all possible problems, specially given
that this machine doesn't appear to have a mainline DT (and its OF
implementation looks a bit buggy).

Thanks,

	M.
diff mbox series

Patch

diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
index 14618dc0bd396..af9cba4a51c2e 100644
--- a/drivers/irqchip/irq-mmp.c
+++ b/drivers/irqchip/irq-mmp.c
@@ -424,9 +424,9 @@  IRQCHIP_DECLARE(mmp2_intc, "mrvl,mmp2-intc", mmp2_of_init);
 static int __init mmp2_mux_of_init(struct device_node *node,
 				   struct device_node *parent)
 {
-	struct resource res;
 	int i, ret, irq, j = 0;
 	u32 nr_irqs, mfp_irq;
+	u32 reg[4];
 
 	if (!parent)
 		return -ENODEV;
@@ -438,18 +438,20 @@  static int __init mmp2_mux_of_init(struct device_node *node,
 		pr_err("Not found mrvl,intc-nr-irqs property\n");
 		return -EINVAL;
 	}
-	ret = of_address_to_resource(node, 0, &res);
+
+	/*
+	 * For historical reasonsm, the "regs" property of the
+	 * mrvl,mmp2-mux-intc is not a regular * "regs" property containing
+	 * addresses on the parent bus, but offsets from the intc's base.
+	 * That is why we can't use of_address_to_resource() here.
+	 */
+	ret = of_property_read_u32_array(node, "reg", reg, ARRAY_SIZE(reg));
 	if (ret < 0) {
 		pr_err("Not found reg property\n");
 		return -EINVAL;
 	}
-	icu_data[i].reg_status = mmp_icu_base + res.start;
-	ret = of_address_to_resource(node, 1, &res);
-	if (ret < 0) {
-		pr_err("Not found reg property\n");
-		return -EINVAL;
-	}
-	icu_data[i].reg_mask = mmp_icu_base + res.start;
+	icu_data[i].reg_status = mmp_icu_base + reg[0];
+	icu_data[i].reg_mask = mmp_icu_base + reg[2];
 	icu_data[i].cascade_irq = irq_of_parse_and_map(node, 0);
 	if (!icu_data[i].cascade_irq)
 		return -EINVAL;