[PATCH v5] irqchip/mmp: only touch the PJ4 & FIQ bits on enable/disable

[PATCH v5] irqchip/mmp: only touch the PJ4 & FIQ bits on enable/disable

[Lubomir Rintel]

Resetting the bit 4 disables the interrupt delivery to the "secure
processor" core. This breaks the keyboard on a OLPC XO 1.75 laptop,
where the firmware running on the "secure processor" bit-bangs the
PS/2 protocol over the GPIO lines.

It is not clear what the rest of the bits are and Marvel was unhelpful
when asked for documentation. Aside from the SP bit, there are probably
priority bits.

Leaving the unknown bits as the firmware set them up seems to be a wiser
course of action compared to just turning them off.

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

---
Changes since v4:
- Remove unused ICU_INT_ROUTE_SP_IRQ define
- Try to further clarify the commit message

Changes since v3:
- Use #defined instead of integer literals

Changes since v2:
- Correct subsystem maintainers on Cc (irqchip)

Changes since v1:
- Adjusted wording & ack from Pavel
---
 drivers/irqchip/irq-mmp.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
index 37a54797a137..fac8f1365f76 100644
--- a/drivers/irqchip/irq-mmp.c
+++ b/drivers/irqchip/irq-mmp.c
@@ -34,6 +34,9 @@
 #define SEL_INT_PENDING		(1 << 6)
 #define SEL_INT_NUM_MASK	0x3f
 
+#define MMP2_ICU_INT_ROUTE_PJ4_IRQ	(1 << 5)
+#define MMP2_ICU_INT_ROUTE_PJ4_FIQ	(1 << 6)
+
 struct icu_chip_data {
 	int			nr_irqs;
 	unsigned int		virq_base;
@@ -190,7 +193,8 @@ static const struct mmp_intc_conf mmp_conf = {
 static const struct mmp_intc_conf mmp2_conf = {
 	.conf_enable	= 0x20,
 	.conf_disable	= 0x0,
-	.conf_mask	= 0x7f,
+	.conf_mask	= MMP2_ICU_INT_ROUTE_PJ4_IRQ |
+			  MMP2_ICU_INT_ROUTE_PJ4_FIQ,
 };
 
 static void __exception_irq_entry mmp_handle_irq(struct pt_regs *regs)
-- 
2.20.1

Re: [PATCH v5] irqchip/mmp: only touch the PJ4 & FIQ bits on enable/disable

[Marc Zyngier]

I guess the subject is supposed to read: "only touch the PJ4 *IRQ* & FIQ
bits on enable/disable", right?

If that's the case, let me know, and I'll fix it up when applying it.

On 28/01/2019 15:59, Lubomir Rintel wrote:
> Resetting the bit 4 disables the interrupt delivery to the "secure
> processor" core. This breaks the keyboard on a OLPC XO 1.75 laptop,
> where the firmware running on the "secure processor" bit-bangs the
> PS/2 protocol over the GPIO lines.
> 
> It is not clear what the rest of the bits are and Marvel was unhelpful
> when asked for documentation. Aside from the SP bit, there are probably
> priority bits.
> 
> Leaving the unknown bits as the firmware set them up seems to be a wiser
> course of action compared to just turning them off.
> 
> Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> Acked-by: Pavel Machek <pavel@ucw.cz>
> 
> ---
> Changes since v4:
> - Remove unused ICU_INT_ROUTE_SP_IRQ define
> - Try to further clarify the commit message
> 
> Changes since v3:
> - Use #defined instead of integer literals
> 
> Changes since v2:
> - Correct subsystem maintainers on Cc (irqchip)
> 
> Changes since v1:
> - Adjusted wording & ack from Pavel
> ---
>  drivers/irqchip/irq-mmp.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
> index 37a54797a137..fac8f1365f76 100644
> --- a/drivers/irqchip/irq-mmp.c
> +++ b/drivers/irqchip/irq-mmp.c
> @@ -34,6 +34,9 @@
>  #define SEL_INT_PENDING		(1 << 6)
>  #define SEL_INT_NUM_MASK	0x3f
>  
> +#define MMP2_ICU_INT_ROUTE_PJ4_IRQ	(1 << 5)
> +#define MMP2_ICU_INT_ROUTE_PJ4_FIQ	(1 << 6)
> +
>  struct icu_chip_data {
>  	int			nr_irqs;
>  	unsigned int		virq_base;
> @@ -190,7 +193,8 @@ static const struct mmp_intc_conf mmp_conf = {
>  static const struct mmp_intc_conf mmp2_conf = {
>  	.conf_enable	= 0x20,
>  	.conf_disable	= 0x0,
> -	.conf_mask	= 0x7f,
> +	.conf_mask	= MMP2_ICU_INT_ROUTE_PJ4_IRQ |
> +			  MMP2_ICU_INT_ROUTE_PJ4_FIQ,
>  };
>  
>  static void __exception_irq_entry mmp_handle_irq(struct pt_regs *regs)
> 

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny...

Re: [PATCH v5] irqchip/mmp: only touch the PJ4 & FIQ bits on enable/disable

[Lubomir Rintel]

On Mon, 2019-01-28 at 18:35 +0000, Marc Zyngier wrote:
> I guess the subject is supposed to read: "only touch the PJ4 *IRQ* & FIQ
> bits on enable/disable", right?
> 
> If that's the case, let me know, and I'll fix it up when applying it.

Yes, that would make more sense.

Thank you
Lubo

> On 28/01/2019 15:59, Lubomir Rintel wrote:
> > Resetting the bit 4 disables the interrupt delivery to the "secure
> > processor" core. This breaks the keyboard on a OLPC XO 1.75 laptop,
> > where the firmware running on the "secure processor" bit-bangs the
> > PS/2 protocol over the GPIO lines.
> > 
> > It is not clear what the rest of the bits are and Marvel was unhelpful
> > when asked for documentation. Aside from the SP bit, there are probably
> > priority bits.
> > 
> > Leaving the unknown bits as the firmware set them up seems to be a wiser
> > course of action compared to just turning them off.
> > 
> > Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
> > Acked-by: Pavel Machek <pavel@ucw.cz>
> > 
> > ---
> > Changes since v4:
> > - Remove unused ICU_INT_ROUTE_SP_IRQ define
> > - Try to further clarify the commit message
> > 
> > Changes since v3:
> > - Use #defined instead of integer literals
> > 
> > Changes since v2:
> > - Correct subsystem maintainers on Cc (irqchip)
> > 
> > Changes since v1:
> > - Adjusted wording & ack from Pavel
> > ---
> >  drivers/irqchip/irq-mmp.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/irqchip/irq-mmp.c b/drivers/irqchip/irq-mmp.c
> > index 37a54797a137..fac8f1365f76 100644
> > --- a/drivers/irqchip/irq-mmp.c
> > +++ b/drivers/irqchip/irq-mmp.c
> > @@ -34,6 +34,9 @@
> >  #define SEL_INT_PENDING		(1 << 6)
> >  #define SEL_INT_NUM_MASK	0x3f
> >  
> > +#define MMP2_ICU_INT_ROUTE_PJ4_IRQ	(1 << 5)
> > +#define MMP2_ICU_INT_ROUTE_PJ4_FIQ	(1 << 6)
> > +
> >  struct icu_chip_data {
> >  	int			nr_irqs;
> >  	unsigned int		virq_base;
> > @@ -190,7 +193,8 @@ static const struct mmp_intc_conf mmp_conf = {
> >  static const struct mmp_intc_conf mmp2_conf = {
> >  	.conf_enable	= 0x20,
> >  	.conf_disable	= 0x0,
> > -	.conf_mask	= 0x7f,
> > +	.conf_mask	= MMP2_ICU_INT_ROUTE_PJ4_IRQ |
> > +			  MMP2_ICU_INT_ROUTE_PJ4_FIQ,
> >  };
> >  
> >  static void __exception_irq_entry mmp_handle_irq(struct pt_regs *regs)
> > 
> 
> Thanks,
> 
> 	M.