[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Vitaly Andrianov]

This commit copies implementation of the find_next_zero_bit() from
git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07

The function is required to enable MCAST_TFTP support for ARM platforms.

Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
---

 arch/arm/include/asm/bitops.h | 43 ++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h
index 597dafb..9b78043 100644
--- a/arch/arm/include/asm/bitops.h
+++ b/arch/arm/include/asm/bitops.h
@@ -95,9 +95,6 @@ static inline int __test_and_change_bit(int nr, volatile void *addr)
 	return (old & mask) != 0;
 }
 
-extern int find_first_zero_bit(void * addr, unsigned size);
-extern int find_next_zero_bit(void * addr, int size, int offset);
-
 /*
  * This routine doesn't need to be atomic.
  */
@@ -129,6 +126,43 @@ static inline unsigned long ffz(unsigned long word)
 	return k;
 }
 
+static inline int find_next_zero_bit(void *addr, int size, int offset)
+{
+	unsigned long *p = ((unsigned long *)addr) + (offset >> 5);
+	unsigned long result = offset & ~31UL;
+	unsigned long tmp;
+
+	if (offset >= size)
+		return size;
+	size -= result;
+	offset &= 31UL;
+	if (offset) {
+		tmp = *(p++);
+		tmp |= ~0UL >> (32-offset);
+		if (size < 32)
+			goto found_first;
+		if (~tmp)
+			goto found_middle;
+		size -= 32;
+		result += 32;
+	}
+	while (size & ~31UL) {
+		tmp = *(p++);
+		if (~tmp)
+			goto found_middle;
+		result += 32;
+		size -= 32;
+	}
+	if (!size)
+		return result;
+	tmp = *p;
+
+found_first:
+	tmp |= ~0UL >> size;
+found_middle:
+	return result + ffz(tmp);
+}
+
 /*
  * hweightN: returns the hamming weight (i.e. the number
  * of bits set) of a N-bit word
@@ -138,6 +172,9 @@ static inline unsigned long ffz(unsigned long word)
 #define hweight16(x) generic_hweight16(x)
 #define hweight8(x) generic_hweight8(x)
 
+#define find_first_zero_bit(addr, size) \
+	find_next_zero_bit((addr), (size), 0)
+
 #define ext2_set_bit			test_and_set_bit
 #define ext2_clear_bit			test_and_clear_bit
 #define ext2_test_bit			test_bit
-- 
1.9.1

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Albert ARIBAUD]

Hello Vitaly,

On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
wrote:
> This commit copies implementation of the find_next_zero_bit() from
> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
> 
> The function is required to enable MCAST_TFTP support for ARM platforms.

Which mainline board needs this?

> Signed-off-by: Vitaly Andrianov <vitalya@ti.com>

Amicalement,
-- 
Albert.

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Vitaly Andrianov]

On 02/05/2015 12:52 PM, Albert ARIBAUD wrote:
> Hello Vitaly,
>
> On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
> wrote:
>> This commit copies implementation of the find_next_zero_bit() from
>> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
>>
>> The function is required to enable MCAST_TFTP support for ARM platforms.
>
> Which mainline board needs this?

TI Keystone2 EVMs

>
>> Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
>
> Amicalement,
>

-Vitaly

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Albert ARIBAUD]

Hello Vitaly,

On Wed, 11 Feb 2015 14:11:12 -0500, Vitaly Andrianov <vitalya@ti.com>
wrote:
> 
> 
> On 02/05/2015 12:52 PM, Albert ARIBAUD wrote:
> > Hello Vitaly,
> >
> > On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
> > wrote:
> >> This commit copies implementation of the find_next_zero_bit() from
> >> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
> >>
> >> The function is required to enable MCAST_TFTP support for ARM platforms.
> >
> > Which mainline board needs this?
> 
> TI Keystone2 EVMs

Just to make sure: this is actually replacing a 'normal' function with
an inline one. So the function /was/ available before this patch,
right?

> -Vitaly

Amicalement,
-- 
Albert.

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Vitaly Andrianov]

Hello Albert,

On 03/27/2015 11:54 AM, Albert ARIBAUD wrote:
> Hello Vitaly,
>
> On Wed, 11 Feb 2015 14:11:12 -0500, Vitaly Andrianov <vitalya@ti.com>
> wrote:
>>
>>
>> On 02/05/2015 12:52 PM, Albert ARIBAUD wrote:
>>> Hello Vitaly,
>>>
>>> On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
>>> wrote:
>>>> This commit copies implementation of the find_next_zero_bit() from
>>>> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
>>>>
>>>> The function is required to enable MCAST_TFTP support for ARM platforms.
>>>
>>> Which mainline board needs this?
>>
>> TI Keystone2 EVMs
>
> Just to make sure: this is actually replacing a 'normal' function with
> an inline one. So the function /was/ available before this patch,
> right?
>
What inline function are you talking about?
I couldn't find this function for ARM. That is why I copied it from MIPS.

>> -Vitaly
>
> Amicalement,
>

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Albert ARIBAUD]

Hello Vitaly,

On Fri, 27 Mar 2015 15:06:15 -0400, Vitaly Andrianov <vitalya@ti.com>
wrote:
> Hello Albert,
> 
> On 03/27/2015 11:54 AM, Albert ARIBAUD wrote:
> > Hello Vitaly,
> >
> > On Wed, 11 Feb 2015 14:11:12 -0500, Vitaly Andrianov <vitalya@ti.com>
> > wrote:
> >>
> >>
> >> On 02/05/2015 12:52 PM, Albert ARIBAUD wrote:
> >>> Hello Vitaly,
> >>>
> >>> On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
> >>> wrote:
> >>>> This commit copies implementation of the find_next_zero_bit() from
> >>>> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
> >>>>
> >>>> The function is required to enable MCAST_TFTP support for ARM platforms.
> >>>
> >>> Which mainline board needs this?
> >>
> >> TI Keystone2 EVMs
> >
> > Just to make sure: this is actually replacing a 'normal' function with
> > an inline one. So the function /was/ available before this patch,
> > right?
> >
> What inline function are you talking about?

The one you are adding with this patch.

> I couldn't find this function for ARM. That is why I copied it from MIPS.

Thanks -- I had noticed that you were removing extern declarations for
find_first_zero_bit() and find_next_zero_bit() and I was surprised
that this removal was not explained in the commit message, and I had
not realized that the corresponding function definitions did not exist.

I'll apply your patch and add a note in the commit message explaining
the removal.

Amicalement,
-- 
Albert.

[U-Boot] [PATCH] arm: implement find_next_zero_bit function

[Albert ARIBAUD]

Hello Vitaly,

On Thu, 5 Feb 2015 11:24:46 -0500, Vitaly Andrianov <vitalya@ti.com>
wrote:
> This commit copies implementation of the find_next_zero_bit() from
> git://git.denx.de/u-boot.git/arch/mips/include/asm/bitops.h. v2014.07
> 
> The function is required to enable MCAST_TFTP support for ARM platforms.
> 
> Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
> ---
> 
>  arch/arm/include/asm/bitops.h | 43 ++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 40 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/include/asm/bitops.h b/arch/arm/include/asm/bitops.h
> index 597dafb..9b78043 100644
> --- a/arch/arm/include/asm/bitops.h
> +++ b/arch/arm/include/asm/bitops.h
> @@ -95,9 +95,6 @@ static inline int __test_and_change_bit(int nr, volatile void *addr)
>  	return (old & mask) != 0;
>  }
>  
> -extern int find_first_zero_bit(void * addr, unsigned size);
> -extern int find_next_zero_bit(void * addr, int size, int offset);
> -
>  /*
>   * This routine doesn't need to be atomic.
>   */
> @@ -129,6 +126,43 @@ static inline unsigned long ffz(unsigned long word)
>  	return k;
>  }
>  
> +static inline int find_next_zero_bit(void *addr, int size, int offset)
> +{
> +	unsigned long *p = ((unsigned long *)addr) + (offset >> 5);
> +	unsigned long result = offset & ~31UL;
> +	unsigned long tmp;
> +
> +	if (offset >= size)
> +		return size;
> +	size -= result;
> +	offset &= 31UL;
> +	if (offset) {
> +		tmp = *(p++);
> +		tmp |= ~0UL >> (32-offset);
> +		if (size < 32)
> +			goto found_first;
> +		if (~tmp)
> +			goto found_middle;
> +		size -= 32;
> +		result += 32;
> +	}
> +	while (size & ~31UL) {
> +		tmp = *(p++);arm: implement find_next_zero_bit function
> +		if (~tmp)
> +			goto found_middle;
> +		result += 32;
> +		size -= 32;
> +	}
> +	if (!size)
> +		return result;
> +	tmp = *p;
> +
> +found_first:
> +	tmp |= ~0UL >> size;
> +found_middle:
> +	return result + ffz(tmp);
> +}
> +
>  /*
>   * hweightN: returns the hamming weight (i.e. the number
>   * of bits set) of a N-bit word
> @@ -138,6 +172,9 @@ static inline unsigned long ffz(unsigned long word)
>  #define hweight16(x) generic_hweight16(x)
>  #define hweight8(x) generic_hweight8(x)
>  
> +#define find_first_zero_bit(addr, size) \
> +	find_next_zero_bit((addr), (size), 0)
> +
>  #define ext2_set_bit			test_and_set_bit
>  #define ext2_clear_bit			test_and_clear_bit
>  #define ext2_test_bit			test_bit
> -- 
> 1.9.1
> 

Applied to u-boot-arm/master, thanks!

Amicalement,
-- 
Albert.