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Message-Id: <E1ooSWZ-000FEA-CU@rmk-PC.armlinux.org.uk>
Date: Fri, 28 Oct 2022 17:48:03 +0100
From: "Russell King (Oracle)" <rmk+kernel@...linux.org.uk>
To: Yury Norov <yury.norov@...il.com>
Cc: Catalin Marinas <catalin.marinas@....com>,
Mark Rutland <mark.rutland@....com>,
Will Deacon <will@...nel.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
Linus Torvalds <torvalds@...ux-foundation.org>,
linux-arm-kernel@...ts.infradead.org
Subject: [PATCH 3/5] ARM: findbit: convert to macros
Since the pairs of _find_first and _find_next functions are pretty
similar, use macros to generate this code. This commit does not
change the generated code.
Signed-off-by: Russell King (Oracle) <rmk+kernel@...linux.org.uk>
---
arch/arm/lib/findbit.S | 158 +++++++++++------------------------------
1 file changed, 42 insertions(+), 116 deletions(-)
diff --git a/arch/arm/lib/findbit.S b/arch/arm/lib/findbit.S
index 256e095d490b..8280f66d38a5 100644
--- a/arch/arm/lib/findbit.S
+++ b/arch/arm/lib/findbit.S
@@ -14,155 +14,81 @@
#include <asm/assembler.h>
.text
-/*
- * Purpose : Find a 'zero' bit
- * Prototype: int find_first_zero_bit(void *addr, unsigned int maxbit);
- */
-ENTRY(_find_first_zero_bit_le)
- teq r1, #0
+ .macro find_first, endian, set, name
+ENTRY(_find_first_\name\()bit_\endian)
+ teq r1, #0
beq 3f
mov r2, #0
1:
+ .ifc \endian, be
+ eor r3, r2, #0x18
+ ARM( ldrb r3, [r0, r3, lsr #3] )
+ THUMB( lsr r3, #3 )
+ THUMB( ldrb r3, [r0, r3] )
+ .else
ARM( ldrb r3, [r0, r2, lsr #3] )
THUMB( lsr r3, r2, #3 )
THUMB( ldrb r3, [r0, r3] )
+ .endif
+ .ifeq \set
eors r3, r3, #0xff @ invert bits
+ .else
+ movs r3, r3
+ .endif
bne .L_found @ any now set - found zero bit
add r2, r2, #8 @ next bit pointer
2: cmp r2, r1 @ any more?
blo 1b
3: mov r0, r1 @ no free bits
ret lr
-ENDPROC(_find_first_zero_bit_le)
+ENDPROC(_find_first_\name\()bit_\endian)
+ .endm
-/*
- * Purpose : Find next 'zero' bit
- * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset)
- */
-ENTRY(_find_next_zero_bit_le)
+ .macro find_next, endian, set, name
+ENTRY(_find_next_\name\()bit_\endian)
cmp r2, r1
bhs 3b
ands ip, r2, #7
beq 1b @ If new byte, goto old routine
+ .ifc \endian, be
+ eor r3, r2, #0x18
+ ARM( ldrb r3, [r0, r3, lsr #3] )
+ THUMB( lsr r3, #3 )
+ THUMB( ldrb r3, [r0, r3] )
+ .else
ARM( ldrb r3, [r0, r2, lsr #3] )
THUMB( lsr r3, r2, #3 )
THUMB( ldrb r3, [r0, r3] )
+ .endif
+ .ifeq \set
eor r3, r3, #0xff @ now looking for a 1 bit
+ .endif
movs r3, r3, lsr ip @ shift off unused bits
bne .L_found
orr r2, r2, #7 @ if zero, then no bits here
add r2, r2, #1 @ align bit pointer
b 2b @ loop for next bit
-ENDPROC(_find_next_zero_bit_le)
+ENDPROC(_find_next_\name\()bit_\endian)
+ .endm
-/*
- * Purpose : Find a 'one' bit
- * Prototype: int find_first_bit(const unsigned long *addr, unsigned int maxbit);
- */
-ENTRY(_find_first_bit_le)
- teq r1, #0
- beq 3f
- mov r2, #0
-1:
- ARM( ldrb r3, [r0, r2, lsr #3] )
- THUMB( lsr r3, r2, #3 )
- THUMB( ldrb r3, [r0, r3] )
- movs r3, r3
- bne .L_found @ any now set - found zero bit
- add r2, r2, #8 @ next bit pointer
-2: cmp r2, r1 @ any more?
- blo 1b
-3: mov r0, r1 @ no free bits
- ret lr
-ENDPROC(_find_first_bit_le)
+ .macro find_bit, endian, set, name
+ find_first \endian, \set, \name
+ find_next \endian, \set, \name
+ .endm
-/*
- * Purpose : Find next 'one' bit
- * Prototype: int find_next_zero_bit(void *addr, unsigned int maxbit, int offset)
- */
-ENTRY(_find_next_bit_le)
- cmp r2, r1
- bhs 3b
- ands ip, r2, #7
- beq 1b @ If new byte, goto old routine
- ARM( ldrb r3, [r0, r2, lsr #3] )
- THUMB( lsr r3, r2, #3 )
- THUMB( ldrb r3, [r0, r3] )
- movs r3, r3, lsr ip @ shift off unused bits
- bne .L_found
- orr r2, r2, #7 @ if zero, then no bits here
- add r2, r2, #1 @ align bit pointer
- b 2b @ loop for next bit
-ENDPROC(_find_next_bit_le)
+/* _find_first_zero_bit_le and _find_next_zero_bit_le */
+ find_bit le, 0, zero_
-#ifdef __ARMEB__
+/* _find_first_bit_le and _find_next_bit_le */
+ find_bit le, 1
-ENTRY(_find_first_zero_bit_be)
- teq r1, #0
- beq 3f
- mov r2, #0
-1: eor r3, r2, #0x18 @ big endian byte ordering
- ARM( ldrb r3, [r0, r3, lsr #3] )
- THUMB( lsr r3, #3 )
- THUMB( ldrb r3, [r0, r3] )
- eors r3, r3, #0xff @ invert bits
- bne .L_found @ any now set - found zero bit
- add r2, r2, #8 @ next bit pointer
-2: cmp r2, r1 @ any more?
- blo 1b
-3: mov r0, r1 @ no free bits
- ret lr
-ENDPROC(_find_first_zero_bit_be)
+#ifdef __ARMEB__
-ENTRY(_find_next_zero_bit_be)
- cmp r2, r1
- bhs 3b
- ands ip, r2, #7
- beq 1b @ If new byte, goto old routine
- eor r3, r2, #0x18 @ big endian byte ordering
- ARM( ldrb r3, [r0, r3, lsr #3] )
- THUMB( lsr r3, #3 )
- THUMB( ldrb r3, [r0, r3] )
- eor r3, r3, #0xff @ now looking for a 1 bit
- movs r3, r3, lsr ip @ shift off unused bits
- bne .L_found
- orr r2, r2, #7 @ if zero, then no bits here
- add r2, r2, #1 @ align bit pointer
- b 2b @ loop for next bit
-ENDPROC(_find_next_zero_bit_be)
+/* _find_first_zero_bit_be and _find_next_zero_bit_be */
+ find_bit be, 0, zero_
-ENTRY(_find_first_bit_be)
- teq r1, #0
- beq 3f
- mov r2, #0
-1: eor r3, r2, #0x18 @ big endian byte ordering
- ARM( ldrb r3, [r0, r3, lsr #3] )
- THUMB( lsr r3, #3 )
- THUMB( ldrb r3, [r0, r3] )
- movs r3, r3
- bne .L_found @ any now set - found zero bit
- add r2, r2, #8 @ next bit pointer
-2: cmp r2, r1 @ any more?
- blo 1b
-3: mov r0, r1 @ no free bits
- ret lr
-ENDPROC(_find_first_bit_be)
-
-ENTRY(_find_next_bit_be)
- cmp r2, r1
- bhs 3b
- ands ip, r2, #7
- beq 1b @ If new byte, goto old routine
- eor r3, r2, #0x18 @ big endian byte ordering
- ARM( ldrb r3, [r0, r3, lsr #3] )
- THUMB( lsr r3, #3 )
- THUMB( ldrb r3, [r0, r3] )
- movs r3, r3, lsr ip @ shift off unused bits
- bne .L_found
- orr r2, r2, #7 @ if zero, then no bits here
- add r2, r2, #1 @ align bit pointer
- b 2b @ loop for next bit
-ENDPROC(_find_next_bit_be)
+/* _find_first_bit_be and _find_next_bit_be */
+ find_bit be, 1
#endif
--
2.30.2
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