[PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Tomi Valkeinen]

On x64 we get:

drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]

The registers are 32 bit, so fix by casting to u32.

Fixes: fb43aa0acdfd ("drm: bridge: Add support for Cadence MHDP8546 DPI/DP bridge")
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
---
 drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
index 621ebdbff8a3..d0c65610ebb5 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
@@ -748,7 +748,7 @@ static int cdns_mhdp_fw_activate(const struct firmware *fw,
 	 * bridge should already be detached.
 	 */
 	if (mhdp->bridge_attached)
-		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
+		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
 		       mhdp->regs + CDNS_APB_INT_MASK);
 
 	spin_unlock(&mhdp->start_lock);
@@ -1689,7 +1689,7 @@ static int cdns_mhdp_attach(struct drm_bridge *bridge,
 
 	/* Enable SW event interrupts */
 	if (hw_ready)
-		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
+		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
 		       mhdp->regs + CDNS_APB_INT_MASK);
 
 	return 0;
@@ -2122,7 +2122,7 @@ static void cdns_mhdp_bridge_hpd_enable(struct drm_bridge *bridge)
 
 	/* Enable SW event interrupts */
 	if (mhdp->bridge_attached)
-		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
+		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
 		       mhdp->regs + CDNS_APB_INT_MASK);
 }
 
-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Tomi Valkeinen]

On 23/09/2020 11:30, Tomi Valkeinen wrote:
> On x64 we get:
> 
> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
> 
> The registers are 32 bit, so fix by casting to u32.
> 
> Fixes: fb43aa0acdfd ("drm: bridge: Add support for Cadence MHDP8546 DPI/DP bridge")
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

I forgot to add

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>

 Tomi

-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Wed, Sep 23, 2020 at 11:30:57AM +0300, Tomi Valkeinen wrote:
> On x64 we get:
> 
> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
> 
> The registers are 32 bit, so fix by casting to u32.

I wonder if we need a BIT32 macro... This is a common issue, it would be
nice to handle it in the macros that define register fields.

> Fixes: fb43aa0acdfd ("drm: bridge: Add support for Cadence MHDP8546 DPI/DP bridge")
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> ---
>  drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> index 621ebdbff8a3..d0c65610ebb5 100644
> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> @@ -748,7 +748,7 @@ static int cdns_mhdp_fw_activate(const struct firmware *fw,
>  	 * bridge should already be detached.
>  	 */
>  	if (mhdp->bridge_attached)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);
>  
>  	spin_unlock(&mhdp->start_lock);
> @@ -1689,7 +1689,7 @@ static int cdns_mhdp_attach(struct drm_bridge *bridge,
>  
>  	/* Enable SW event interrupts */
>  	if (hw_ready)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);
>  
>  	return 0;
> @@ -2122,7 +2122,7 @@ static void cdns_mhdp_bridge_hpd_enable(struct drm_bridge *bridge)
>  
>  	/* Enable SW event interrupts */
>  	if (mhdp->bridge_attached)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);
>  }
>  

-- 
Regards,

Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Tomi Valkeinen]

On 24/09/2020 14:48, Laurent Pinchart wrote:
> Hi Tomi,
> 
> Thank you for the patch.
> 
> On Wed, Sep 23, 2020 at 11:30:57AM +0300, Tomi Valkeinen wrote:
>> On x64 we get:
>>
>> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
>>
>> The registers are 32 bit, so fix by casting to u32.
> 
> I wonder if we need a BIT32 macro... This is a common issue, it would be
> nice to handle it in the macros that define register fields.

That's probably a good idea. I think

#define BIT32(nr) (1u << (nr))

should work correct on all archs. Although I'm not quite sure if nr should be cast to u32, but in my
tests a u64 nr doesn't cause type promotion to u64.

Anyway, I'd like to merge this fix as it is to get rid of the warning for the merge window.

 Tomi

-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Laurent Pinchart]

On Fri, Sep 25, 2020 at 10:36:44AM +0300, Tomi Valkeinen wrote:
> On 24/09/2020 14:48, Laurent Pinchart wrote:
> > Hi Tomi,
> > 
> > Thank you for the patch.
> > 
> > On Wed, Sep 23, 2020 at 11:30:57AM +0300, Tomi Valkeinen wrote:
> >> On x64 we get:
> >>
> >> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
> >>
> >> The registers are 32 bit, so fix by casting to u32.
> > 
> > I wonder if we need a BIT32 macro... This is a common issue, it would be
> > nice to handle it in the macros that define register fields.
> 
> That's probably a good idea. I think
> 
> #define BIT32(nr) (1u << (nr))
> 
> should work correct on all archs. Although I'm not quite sure if nr should be cast to u32, but in my
> tests a u64 nr doesn't cause type promotion to u64.

I don't think we need to support nr values larger than 2^32-1 ;-)

> Anyway, I'd like to merge this fix as it is to get rid of the warning for the merge window.

Sounds good to me.

-- 
Regards,

Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Tomi Valkeinen]

On 25/09/2020 15:00, Laurent Pinchart wrote:
> On Fri, Sep 25, 2020 at 10:36:44AM +0300, Tomi Valkeinen wrote:
>> On 24/09/2020 14:48, Laurent Pinchart wrote:
>>> Hi Tomi,
>>>
>>> Thank you for the patch.
>>>
>>> On Wed, Sep 23, 2020 at 11:30:57AM +0300, Tomi Valkeinen wrote:
>>>> On x64 we get:
>>>>
>>>> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
>>>>
>>>> The registers are 32 bit, so fix by casting to u32.
>>>
>>> I wonder if we need a BIT32 macro... This is a common issue, it would be
>>> nice to handle it in the macros that define register fields.
>>
>> That's probably a good idea. I think
>>
>> #define BIT32(nr) (1u << (nr))
>>
>> should work correct on all archs. Although I'm not quite sure if nr should be cast to u32, but in my
>> tests a u64 nr doesn't cause type promotion to u64.
> 
> I don't think we need to support nr values larger than 2^32-1 ;-)

That's true, but we might have:

u64 nr = 1;
BIT32(nr)

Afaics, we don't need to cast nr to u32, but maybe that's still the safe thing to do.

>> Anyway, I'd like to merge this fix as it is to get rid of the warning for the merge window.
> 
> Sounds good to me.

Was that a reviewed-by? =)

 Tomi

-- 
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Re: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Laurent Pinchart]

On Fri, Sep 25, 2020 at 03:05:52PM +0300, Tomi Valkeinen wrote:
> On 25/09/2020 15:00, Laurent Pinchart wrote:
> > On Fri, Sep 25, 2020 at 10:36:44AM +0300, Tomi Valkeinen wrote:
> >> On 24/09/2020 14:48, Laurent Pinchart wrote:
> >>> Hi Tomi,
> >>>
> >>> Thank you for the patch.
> >>>
> >>> On Wed, Sep 23, 2020 at 11:30:57AM +0300, Tomi Valkeinen wrote:
> >>>> On x64 we get:
> >>>>
> >>>> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning: conversion from 'long unsigned int' to 'unsigned int' changes value from '18446744073709551613' to '4294967293' [-Woverflow]
> >>>>
> >>>> The registers are 32 bit, so fix by casting to u32.
> >>>
> >>> I wonder if we need a BIT32 macro... This is a common issue, it would be
> >>> nice to handle it in the macros that define register fields.
> >>
> >> That's probably a good idea. I think
> >>
> >> #define BIT32(nr) (1u << (nr))
> >>
> >> should work correct on all archs. Although I'm not quite sure if nr should be cast to u32, but in my
> >> tests a u64 nr doesn't cause type promotion to u64.
> > 
> > I don't think we need to support nr values larger than 2^32-1 ;-)
> 
> That's true, but we might have:
> 
> u64 nr = 1;
> BIT32(nr)
> 
> Afaics, we don't need to cast nr to u32, but maybe that's still the safe thing to do.
> 
> >> Anyway, I'd like to merge this fix as it is to get rid of the warning for the merge window.
> > 
> > Sounds good to me.
> 
> Was that a reviewed-by? =)

Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

-- 
Regards,

Laurent Pinchart
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

RE: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning

[Swapnil Kashinath Jakhade]

Hi Tomi,

Thank you for the patch.

> -----Original Message-----
> From: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Sent: Wednesday, September 23, 2020 2:01 PM
> To: dri-devel@lists.freedesktop.org; Swapnil Kashinath Jakhade
> <sjakhade@cadence.com>; Yuti Suresh Amonkar <yamonkar@cadence.com>
> Cc: Stephen Rothwell <sfr@canb.auug.org.au>; Dave Airlie
> <airlied@linux.ie>; Laurent Pinchart <laurent.pinchart@ideasonboard.com>;
> Tomi Valkeinen <tomi.valkeinen@ti.com>
> Subject: [PATCH] drm: bridge: cdns-mhdp8546: fix compile warning
> 
> EXTERNAL MAIL
> 
> 
> On x64 we get:
> 
> drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c:751:10: warning:
> conversion from 'long unsigned int' to 'unsigned int' changes value from
> '18446744073709551613' to '4294967293' [-Woverflow]
> 
> The registers are 32 bit, so fix by casting to u32.
> 
> Fixes: fb43aa0acdfd ("drm: bridge: Add support for Cadence MHDP8546
> DPI/DP bridge")
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> ---
>  drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> index 621ebdbff8a3..d0c65610ebb5 100644
> --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c
> @@ -748,7 +748,7 @@ static int cdns_mhdp_fw_activate(const struct
> firmware *fw,
>  	 * bridge should already be detached.
>  	 */
>  	if (mhdp->bridge_attached)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);
> 
>  	spin_unlock(&mhdp->start_lock);
> @@ -1689,7 +1689,7 @@ static int cdns_mhdp_attach(struct drm_bridge
> *bridge,
> 
>  	/* Enable SW event interrupts */
>  	if (hw_ready)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);
> 
>  	return 0;
> @@ -2122,7 +2122,7 @@ static void cdns_mhdp_bridge_hpd_enable(struct
> drm_bridge *bridge)
> 
>  	/* Enable SW event interrupts */
>  	if (mhdp->bridge_attached)
> -		writel(~CDNS_APB_INT_MASK_SW_EVENT_INT,
> +		writel(~(u32)CDNS_APB_INT_MASK_SW_EVENT_INT,
>  		       mhdp->regs + CDNS_APB_INT_MASK);  }
> 

Reviewed-by: Swapnil Jakhade <sjakhade@cadence.com>

Thanks,
Swapnil
> --
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel