[patch 2.6.29-rc2] palm_bk3710 buildfix

[patch 2.6.29-rc2] palm_bk3710 buildfix

[David Brownell]

From: David Brownell <dbrownell@users.sourceforge.net>
Subject: drivers/ide/palm_bk3710.c buildfix

  CC      drivers/ide/palm_bk3710.o
drivers/ide/palm_bk3710.c: In function 'palm_bk3710_probe':
drivers/ide/palm_bk3710.c:382: warning: assignment makes integer from pointer without a cast

Someone should fix hw_regs_t to neither be a typedef, nor
use "unsigned long" where it should use "void __iomem *".

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
---
 drivers/ide/palm_bk3710.c |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/drivers/ide/palm_bk3710.c
+++ b/drivers/ide/palm_bk3710.c
@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
 {
 	struct clk *clk;
 	struct resource *mem, *irq;
-	unsigned long base, rate;
+	void __iomem *base;
+	unsigned long rate;
 	int i, rc;
 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
 
@@ -382,11 +383,13 @@ static int __init palm_bk3710_probe(stru
 	base = IO_ADDRESS(mem->start);
 
 	/* Configure the Palm Chip controller */
-	palm_bk3710_chipinit((void __iomem *)base);
+	palm_bk3710_chipinit(base);
 
 	for (i = 0; i < IDE_NR_PORTS - 2; i++)
-		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
-	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
+		hw.io_ports_array[i] = (unsigned long)
+				(base + IDE_PALM_ATA_PRI_REG_OFFSET + i);
+	hw.io_ports.ctl_addr = (unsigned long)
+			(base + IDE_PALM_ATA_PRI_CTL_OFFSET);
 	hw.irq = irq->start;
 	hw.dev = &pdev->dev;
 	hw.chipset = ide_palm3710;

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Hello.

David Brownell wrote:

>   CC      drivers/ide/palm_bk3710.o
> drivers/ide/palm_bk3710.c: In function 'palm_bk3710_probe':
> drivers/ide/palm_bk3710.c:382: warning: assignment makes integer from pointer without a cast

> Someone should fix hw_regs_t to neither be a typedef, nor
> use "unsigned long" where it should use "void __iomem *".

    It cannot use pointers of course -- as the addresses can be I/O ports.

> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

> --- a/drivers/ide/palm_bk3710.c
> +++ b/drivers/ide/palm_bk3710.c
> @@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
>  {
>  	struct clk *clk;
>  	struct resource *mem, *irq;
> -	unsigned long base, rate;
> +	void __iomem *base;
> +	unsigned long rate;
>  	int i, rc;
>  	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
>  
> @@ -382,11 +383,13 @@ static int __init palm_bk3710_probe(stru
>  	base = IO_ADDRESS(mem->start);
>  
>  	/* Configure the Palm Chip controller */
> -	palm_bk3710_chipinit((void __iomem *)base);
> +	palm_bk3710_chipinit(base);
>  
>  	for (i = 0; i < IDE_NR_PORTS - 2; i++)
> -		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
> -	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
> +		hw.io_ports_array[i] = (unsigned long)
> +				(base + IDE_PALM_ATA_PRI_REG_OFFSET + i);
> +	hw.io_ports.ctl_addr = (unsigned long)
> +			(base + IDE_PALM_ATA_PRI_CTL_OFFSET);

    Ugh. I suggest adding another variable...

--- a/drivers/ide/palm_bk3710.c
+++ b/drivers/ide/palm_bk3710.c
@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
  {
  	struct clk *clk;
  	struct resource *mem, *irq;
  	unsigned long base, rate;
+	void __iomem *regs;
  	int i, rc;
  	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };

@@ -379,11 +380,11 @@ static int __init palm_bk3710_probe(stru
  		return -EBUSY;
  	}

- 	base = IO_ADDRESS(mem->start);
+ 	regs = IO_ADDRESS(mem->start);

  	/* Configure the Palm Chip controller */
-	palm_bk3710_chipinit((void __iomem *)base);
+	palm_bk3710_chipinit(regs);

+	base = (unsigned long)regs;
  	for (i = 0; i < IDE_NR_PORTS - 2; i++)
  		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
  	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;

MBR, Sergei

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[David Brownell]

On Sunday 18 January 2009, Sergei Shtylyov wrote:
> > Someone should fix hw_regs_t to neither be a typedef, nor
> > use "unsigned long" where it should use "void __iomem *".
> 
>     It cannot use pointers of course -- as the addresses can be I/O ports.

It could use the ioread*() calls, which take pointers
and handle both types of I/O in a type-safe manner.

- Dave

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Hello.

David Brownell wrote:
> On Sunday 18 January 2009, Sergei Shtylyov wrote:
>   
>>> Someone should fix hw_regs_t to neither be a typedef, nor
>>> use "unsigned long" where it should use "void __iomem *".
>>>       
>>     It cannot use pointers of course -- as the addresses can be I/O ports.
>>     
>
> It could use the ioread*() calls, which take pointers
> and handle both types of I/O in a type-safe manner.
>   

   Probably they can... though using those would only slow down register 
access on x86.

> - Dave

WBR, Sergei

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Hello, I wrote:

>>>> Someone should fix hw_regs_t to neither be a typedef, nor
>>>> use "unsigned long" where it should use "void __iomem *".
>>>>       
>>>     It cannot use pointers of course -- as the addresses can be I/O 
>>> ports.
>>>     
>>
>> It could use the ioread*() calls, which take pointers
>> and handle both types of I/O in a type-safe manner.
>>   
>
>   Probably they can... though using those would only slow down 
> register access on x86.

   ... and cause code bloat due to switching to real function calls from 
inlines which now should render into in/out isns.

> - Dave

WBR, Sergei

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Bartlomiej Zolnierkiewicz]

On Sunday 18 January 2009, Sergei Shtylyov wrote:
> Hello.
> 
> David Brownell wrote:
> 
> >   CC      drivers/ide/palm_bk3710.o
> > drivers/ide/palm_bk3710.c: In function 'palm_bk3710_probe':
> > drivers/ide/palm_bk3710.c:382: warning: assignment makes integer from pointer without a cast
> 
> > Someone should fix hw_regs_t to neither be a typedef, nor
> > use "unsigned long" where it should use "void __iomem *".
> 
>     It cannot use pointers of course -- as the addresses can be I/O ports.
> 
> > Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
> 
> > --- a/drivers/ide/palm_bk3710.c
> > +++ b/drivers/ide/palm_bk3710.c
> > @@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
> >  {
> >  	struct clk *clk;
> >  	struct resource *mem, *irq;
> > -	unsigned long base, rate;
> > +	void __iomem *base;
> > +	unsigned long rate;
> >  	int i, rc;
> >  	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
> >  
> > @@ -382,11 +383,13 @@ static int __init palm_bk3710_probe(stru
> >  	base = IO_ADDRESS(mem->start);
> >  
> >  	/* Configure the Palm Chip controller */
> > -	palm_bk3710_chipinit((void __iomem *)base);
> > +	palm_bk3710_chipinit(base);
> >  
> >  	for (i = 0; i < IDE_NR_PORTS - 2; i++)
> > -		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
> > -	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
> > +		hw.io_ports_array[i] = (unsigned long)
> > +				(base + IDE_PALM_ATA_PRI_REG_OFFSET + i);
> > +	hw.io_ports.ctl_addr = (unsigned long)
> > +			(base + IDE_PALM_ATA_PRI_CTL_OFFSET);
> 
>     Ugh. I suggest adding another variable...
> 
> --- a/drivers/ide/palm_bk3710.c
> +++ b/drivers/ide/palm_bk3710.c
> @@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
>   {
>   	struct clk *clk;
>   	struct resource *mem, *irq;
>   	unsigned long base, rate;
> +	void __iomem *regs;
>   	int i, rc;
>   	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
> 
> @@ -379,11 +380,11 @@ static int __init palm_bk3710_probe(stru
>   		return -EBUSY;
>   	}
> 
> - 	base = IO_ADDRESS(mem->start);
> + 	regs = IO_ADDRESS(mem->start);
> 
>   	/* Configure the Palm Chip controller */
> -	palm_bk3710_chipinit((void __iomem *)base);
> +	palm_bk3710_chipinit(regs);
> 
> +	base = (unsigned long)regs;
>   	for (i = 0; i < IDE_NR_PORTS - 2; i++)
>   		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
>   	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;

I applied original patch since having one additional cast has overally lower
complexity than having an additional variable...

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Bartlomiej Zolnierkiewicz]

On Monday 19 January 2009, Sergei Shtylyov wrote:
> Hello, I wrote:
> 
> >>>> Someone should fix hw_regs_t to neither be a typedef, nor
> >>>> use "unsigned long" where it should use "void __iomem *".
> >>>>       
> >>>     It cannot use pointers of course -- as the addresses can be I/O 
> >>> ports.
> >>>     
> >>
> >> It could use the ioread*() calls, which take pointers
> >> and handle both types of I/O in a type-safe manner.
> >>   
> >
> >   Probably they can... though using those would only slow down 
> > register access on x86.
> 
>    ... and cause code bloat due to switching to real function calls from 
> inlines which now should render into in/out isns.

OTOH it would allow to unify a lot of 'if (hwif->host_flags & IDE_HFLAG_MMIO)'
cases so the code may even shrink.  I also suspect that register access slow
down is most likely negligable (we can always measure and check it).

The real reason for not using ioread*() and co. is that not all archs support
them (though I checked some time ago, maybe they do now?) and we don't want to
break IDE support for them.

Thanks,
Bart

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Hello.

Bartlomiej Zolnierkiewicz wrote:

>>>  CC      drivers/ide/palm_bk3710.o
>>>drivers/ide/palm_bk3710.c: In function 'palm_bk3710_probe':
>>>drivers/ide/palm_bk3710.c:382: warning: assignment makes integer from pointer without a cast

>>>Someone should fix hw_regs_t to neither be a typedef, nor
>>>use "unsigned long" where it should use "void __iomem *".

>>    It cannot use pointers of course -- as the addresses can be I/O ports.

>>>Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

>>>--- a/drivers/ide/palm_bk3710.c
>>>+++ b/drivers/ide/palm_bk3710.c
>>>@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
>>> {
>>> 	struct clk *clk;
>>> 	struct resource *mem, *irq;
>>>-	unsigned long base, rate;
>>>+	void __iomem *base;
>>>+	unsigned long rate;
>>> 	int i, rc;
>>> 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
>>> 
>>>@@ -382,11 +383,13 @@ static int __init palm_bk3710_probe(stru
>>> 	base = IO_ADDRESS(mem->start);
>>> 
>>> 	/* Configure the Palm Chip controller */
>>>-	palm_bk3710_chipinit((void __iomem *)base);
>>>+	palm_bk3710_chipinit(base);
>>> 
>>> 	for (i = 0; i < IDE_NR_PORTS - 2; i++)
>>>-		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
>>>-	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
>>>+		hw.io_ports_array[i] = (unsigned long)
>>>+				(base + IDE_PALM_ATA_PRI_REG_OFFSET + i);
>>>+	hw.io_ports.ctl_addr = (unsigned long)
>>>+			(base + IDE_PALM_ATA_PRI_CTL_OFFSET);

>>    Ugh. I suggest adding another variable...

>>--- a/drivers/ide/palm_bk3710.c
>>+++ b/drivers/ide/palm_bk3710.c
>>@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
>>  {
>>  	struct clk *clk;
>>  	struct resource *mem, *irq;
>>  	unsigned long base, rate;
>>+	void __iomem *regs;
>>  	int i, rc;
>>  	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
>>
>>@@ -379,11 +380,11 @@ static int __init palm_bk3710_probe(stru
>>  		return -EBUSY;
>>  	}
>>
>>- 	base = IO_ADDRESS(mem->start);
>>+ 	regs = IO_ADDRESS(mem->start);
>>
>>  	/* Configure the Palm Chip controller */
>>-	palm_bk3710_chipinit((void __iomem *)base);
>>+	palm_bk3710_chipinit(regs);
>>
>>+	base = (unsigned long)regs;
>>  	for (i = 0; i < IDE_NR_PORTS - 2; i++)
>>  		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
>>  	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;

> I applied original patch since having one additional cast has overally lower
> complexity than having an additional variable...

    Grr... as if the stack use aren't optimized by gcc based on the variable 
lifetimes. I can recast the patch myself BTW.

MBR, Sergei

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Bartlomiej Zolnierkiewicz wrote:

>>>>>>Someone should fix hw_regs_t to neither be a typedef, nor
>>>>>>use "unsigned long" where it should use "void __iomem *".

>>>>>    It cannot use pointers of course -- as the addresses can be I/O 
>>>>>ports.

>>>>It could use the ioread*() calls, which take pointers
>>>>and handle both types of I/O in a type-safe manner.

>>>  Probably they can... though using those would only slow down 
>>>register access on x86.

>>   ... and cause code bloat due to switching to real function calls from 
>>inlines which now should render into in/out isns.

> OTOH it would allow to unify a lot of 'if (hwif->host_flags & IDE_HFLAG_MMIO)'
> cases so the code may even shrink.

    It won't shrink as much as it will grow.

> I also suspect that register access slow
> down is most likely negligable (we can always measure and check it).

    I'd agree here but code bloat won't be as negligible considering the IDE 
code's predominant use of I/O ports on x86.

> The real reason for not using ioread*() and co. is that not all archs support
> them (though I checked some time ago, maybe they do now?) and we don't want to
> break IDE support for them.

    Sure. :-)

> Thanks,
> Bart

MBR, Sergei

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Bartlomiej Zolnierkiewicz]

On Monday 19 January 2009, Sergei Shtylyov wrote:
> Hello.
> 
> Bartlomiej Zolnierkiewicz wrote:
> 
> >>>  CC      drivers/ide/palm_bk3710.o
> >>>drivers/ide/palm_bk3710.c: In function 'palm_bk3710_probe':
> >>>drivers/ide/palm_bk3710.c:382: warning: assignment makes integer from pointer without a cast
> 
> >>>Someone should fix hw_regs_t to neither be a typedef, nor
> >>>use "unsigned long" where it should use "void __iomem *".
> 
> >>    It cannot use pointers of course -- as the addresses can be I/O ports.
> 
> >>>Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
> 
> >>>--- a/drivers/ide/palm_bk3710.c
> >>>+++ b/drivers/ide/palm_bk3710.c
> >>>@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
> >>> {
> >>> 	struct clk *clk;
> >>> 	struct resource *mem, *irq;
> >>>-	unsigned long base, rate;
> >>>+	void __iomem *base;
> >>>+	unsigned long rate;
> >>> 	int i, rc;
> >>> 	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
> >>> 
> >>>@@ -382,11 +383,13 @@ static int __init palm_bk3710_probe(stru
> >>> 	base = IO_ADDRESS(mem->start);
> >>> 
> >>> 	/* Configure the Palm Chip controller */
> >>>-	palm_bk3710_chipinit((void __iomem *)base);
> >>>+	palm_bk3710_chipinit(base);
> >>> 
> >>> 	for (i = 0; i < IDE_NR_PORTS - 2; i++)
> >>>-		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
> >>>-	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
> >>>+		hw.io_ports_array[i] = (unsigned long)
> >>>+				(base + IDE_PALM_ATA_PRI_REG_OFFSET + i);
> >>>+	hw.io_ports.ctl_addr = (unsigned long)
> >>>+			(base + IDE_PALM_ATA_PRI_CTL_OFFSET);
> 
> >>    Ugh. I suggest adding another variable...
> 
> >>--- a/drivers/ide/palm_bk3710.c
> >>+++ b/drivers/ide/palm_bk3710.c
> >>@@ -346,7 +346,8 @@ static int __init palm_bk3710_probe(stru
> >>  {
> >>  	struct clk *clk;
> >>  	struct resource *mem, *irq;
> >>  	unsigned long base, rate;
> >>+	void __iomem *regs;
> >>  	int i, rc;
> >>  	hw_regs_t hw, *hws[] = { &hw, NULL, NULL, NULL };
> >>
> >>@@ -379,11 +380,11 @@ static int __init palm_bk3710_probe(stru
> >>  		return -EBUSY;
> >>  	}
> >>
> >>- 	base = IO_ADDRESS(mem->start);
> >>+ 	regs = IO_ADDRESS(mem->start);
> >>
> >>  	/* Configure the Palm Chip controller */
> >>-	palm_bk3710_chipinit((void __iomem *)base);
> >>+	palm_bk3710_chipinit(regs);
> >>
> >>+	base = (unsigned long)regs;
> >>  	for (i = 0; i < IDE_NR_PORTS - 2; i++)
> >>  		hw.io_ports_array[i] = base + IDE_PALM_ATA_PRI_REG_OFFSET + i;
> >>  	hw.io_ports.ctl_addr = base + IDE_PALM_ATA_PRI_CTL_OFFSET;
> 
> > I applied original patch since having one additional cast has overally lower
> > complexity than having an additional variable...
> 
>     Grr... as if the stack use aren't optimized by gcc based on the variable 
> lifetimes. I can recast the patch myself BTW.

I meant code complexity in the maintainance / readability context here.

You know what this variable is for (at least now but a year from now it may
result in a brief WTF moment when looking at base/regs) and that it is short
lived but some random person who will need to update this driver won't...

Thanks,
Bart

Re: [patch 2.6.29-rc2] palm_bk3710 buildfix

[Sergei Shtylyov]

Hello, I wrote:

>>>>>>> Someone should fix hw_regs_t to neither be a typedef, nor
>>>>>>> use "unsigned long" where it should use "void __iomem *".

>>>>>>    It cannot use pointers of course -- as the addresses can be I/O 
>>>>>> ports.

>>>>> It could use the ioread*() calls, which take pointers
>>>>> and handle both types of I/O in a type-safe manner.

>>>>  Probably they can... though using those would only slow down 
>>>> register access on x86.

>>>   ... and cause code bloat due to switching to real function calls 
>>> from inlines which now should render into in/out isns.

>> OTOH it would allow to unify a lot of 'if (hwif->host_flags & 
>> IDE_HFLAG_MMIO)'
>> cases so the code may even shrink.

>    It won't shrink as much as it will grow.

>> I also suspect that register access slow
>> down is most likely negligable (we can always measure and check it).

>    I'd agree here but code bloat won't be as negligible considering the 
> IDE code's predominant use of I/O ports on x86.

    After looking at the current code, the generic IDE code would actually 
benefit from such change, while the most of the controller drivers will only 
be subject to the code bloat.

MBR, Sergei