| Message ID | 1307536233-30089-4-git-send-email-will.deacon@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hello. On 08-06-2011 16:30, Will Deacon wrote: > The HWCAP numbers are defined as constants, each one being a power of 2. > This has become slightly unwieldy now that we have reached 32k. > This patch changes the HWCAP defines to use (1<< n) instead of coding > the constant directly. The values remain unchanged. Perhaps it's better to use BIT(n) macro instead? > Signed-off-by: Will Deacon <will.deacon@arm.com> WBR, Sergei
Sergei, On Mon, Jun 13, 2011 at 02:55:16PM +0100, Sergei Shtylyov wrote: > Hello. > > On 08-06-2011 16:30, Will Deacon wrote: > > > The HWCAP numbers are defined as constants, each one being a power of 2. > > This has become slightly unwieldy now that we have reached 32k. > > > This patch changes the HWCAP defines to use (1<< n) instead of coding > > the constant directly. The values remain unchanged. > > Perhaps it's better to use BIT(n) macro instead? That has the downside of breaking userspace, unless we export linux/bitops.h and remove the __KERNEL__ guards around the BIT macro. Will
On Mon, Jun 13, 2011 at 03:10:13PM +0100, Will Deacon wrote: > Sergei, > > On Mon, Jun 13, 2011 at 02:55:16PM +0100, Sergei Shtylyov wrote: > > Hello. > > > > On 08-06-2011 16:30, Will Deacon wrote: > > > > > The HWCAP numbers are defined as constants, each one being a power of 2. > > > This has become slightly unwieldy now that we have reached 32k. > > > > > This patch changes the HWCAP defines to use (1<< n) instead of coding > > > the constant directly. The values remain unchanged. > > > > Perhaps it's better to use BIT(n) macro instead? > > That has the downside of breaking userspace, unless we export linux/bitops.h > and remove the __KERNEL__ guards around the BIT macro. And potentially break userspace programs which also have a BIT() macro. No, we need to keep using plain C for exported definitions.
diff --git a/arch/arm/include/asm/hwcap.h b/arch/arm/include/asm/hwcap.h index c1062c3..81512db 100644 --- a/arch/arm/include/asm/hwcap.h +++ b/arch/arm/include/asm/hwcap.h @@ -4,22 +4,22 @@ /* * HWCAP flags - for elf_hwcap (in kernel) and AT_HWCAP */ -#define HWCAP_SWP 1 -#define HWCAP_HALF 2 -#define HWCAP_THUMB 4 -#define HWCAP_26BIT 8 /* Play it safe */ -#define HWCAP_FAST_MULT 16 -#define HWCAP_FPA 32 -#define HWCAP_VFP 64 -#define HWCAP_EDSP 128 -#define HWCAP_JAVA 256 -#define HWCAP_IWMMXT 512 -#define HWCAP_CRUNCH 1024 -#define HWCAP_THUMBEE 2048 -#define HWCAP_NEON 4096 -#define HWCAP_VFPv3 8192 -#define HWCAP_VFPv3D16 16384 -#define HWCAP_TLS 32768 +#define HWCAP_SWP (1 << 0) +#define HWCAP_HALF (1 << 1) +#define HWCAP_THUMB (1 << 2) +#define HWCAP_26BIT (1 << 3) /* Play it safe */ +#define HWCAP_FAST_MULT (1 << 4) +#define HWCAP_FPA (1 << 5) +#define HWCAP_VFP (1 << 6) +#define HWCAP_EDSP (1 << 7) +#define HWCAP_JAVA (1 << 8) +#define HWCAP_IWMMXT (1 << 9) +#define HWCAP_CRUNCH (1 << 10) +#define HWCAP_THUMBEE (1 << 11) +#define HWCAP_NEON (1 << 12) +#define HWCAP_VFPv3 (1 << 13) +#define HWCAP_VFPv3D16 (1 << 14) +#define HWCAP_TLS (1 << 15) #if defined(__KERNEL__) && !defined(__ASSEMBLY__) /*
The HWCAP numbers are defined as constants, each one being a power of 2. This has become slightly unwieldy now that we have reached 32k. This patch changes the HWCAP defines to use (1 << n) instead of coding the constant directly. The values remain unchanged. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm/include/asm/hwcap.h | 32 ++++++++++++++++---------------- 1 files changed, 16 insertions(+), 16 deletions(-)