Skip to content

Commit

Permalink
MIPS: Enable cpu_has_clo_clz for MIPS Technologies' platforms
Browse files Browse the repository at this point in the history
Enable cpu_has_clo_clz only when CONFIG_CPU_MIPS32 or CONFIG_CPU_MIPS64
is selected.  This will optimize fls() and __fls() to use CLZ insn, and
eventually ffs() and __ffs() as well.

Malta and MIPSSim are development platforms, and need to take care of
various processor configurations, release rivisions and so on, even
across different MIPS ISAs.  For such platforms we have to be careful,
for instance, with turning on cpu_has_mips{32,64}r[12] features.

As for CLZ, all MIPS32/64 processors support it, regardless of release
revisions.

Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
To: David VomLehn <dvomlehn@cisco.com>
To: macro@linux-mips.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1453/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
  • Loading branch information
Shinya Kuribayashi authored and Ralf Baechle committed Jul 25, 2011
1 parent c2b78c8 commit 5fba096
Show file tree
Hide file tree
Showing 2 changed files with 4 additions and 0 deletions.
2 changes: 2 additions & 0 deletions arch/mips/include/asm/mach-malta/cpu-feature-overrides.h
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,7 @@
/* #define cpu_has_vtag_icache ? */
/* #define cpu_has_dc_aliases ? */
/* #define cpu_has_ic_fills_f_dc ? */
#define cpu_has_clo_clz 1
#define cpu_has_nofpuex 0
/* #define cpu_has_64bits ? */
/* #define cpu_has_64bit_zero_reg ? */
Expand All @@ -58,6 +59,7 @@
/* #define cpu_has_vtag_icache ? */
/* #define cpu_has_dc_aliases ? */
/* #define cpu_has_ic_fills_f_dc ? */
#define cpu_has_clo_clz 1
#define cpu_has_nofpuex 0
/* #define cpu_has_64bits ? */
/* #define cpu_has_64bit_zero_reg ? */
Expand Down
2 changes: 2 additions & 0 deletions arch/mips/include/asm/mach-mipssim/cpu-feature-overrides.h
Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@
/* #define cpu_has_vtag_icache ? */
/* #define cpu_has_dc_aliases ? */
/* #define cpu_has_ic_fills_f_dc ? */
#define cpu_has_clo_clz 1
#define cpu_has_nofpuex 0
/* #define cpu_has_64bits ? */
/* #define cpu_has_64bit_zero_reg ? */
Expand All @@ -56,6 +57,7 @@
/* #define cpu_has_vtag_icache ? */
/* #define cpu_has_dc_aliases ? */
/* #define cpu_has_ic_fills_f_dc ? */
#define cpu_has_clo_clz 1
#define cpu_has_nofpuex 0
/* #define cpu_has_64bits ? */
/* #define cpu_has_64bit_zero_reg ? */
Expand Down

0 comments on commit 5fba096

Please sign in to comment.