avr32: add generic_find_next_le_bit bit function

This patch implements the generic_find_next_le_bit bit function for AVR32
architecture. This is used by EXT4 file system.

Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>

diff --git a/arch/avr32/kernel/avr32_ksyms.c b/arch/avr32/kernel/avr32_ksyms.c
index 84a7d44..11e310c 100644 (file)
--- a/arch/avr32/kernel/avr32_ksyms.c
+++ b/arch/avr32/kernel/avr32_ksyms.c
@@ -58,6 +58,7 @@ EXPORT_SYMBOL(find_first_zero_bit);
 EXPORT_SYMBOL(find_next_zero_bit);
 EXPORT_SYMBOL(find_first_bit);
 EXPORT_SYMBOL(find_next_bit);
+EXPORT_SYMBOL(generic_find_next_le_bit);
 EXPORT_SYMBOL(generic_find_next_zero_le_bit);
 
 /* I/O primitives (lib/io-*.S) */

diff --git a/arch/avr32/lib/findbit.S b/arch/avr32/lib/findbit.S
index c6b91de..997b33b 100644 (file)
--- a/arch/avr32/lib/findbit.S
+++ b/arch/avr32/lib/findbit.S
@@ -123,6 +123,36 @@ ENTRY(find_next_bit)
        brgt    1b
        retal   r11
 
+ENTRY(generic_find_next_le_bit)
+       lsr     r8, r10, 5
+       sub     r9, r11, r10
+       retle   r11
+
+       lsl     r8, 2
+       add     r12, r8
+       andl    r10, 31, COH
+       breq    1f
+
+       /* offset is not word-aligned. Handle the first (32 - r10) bits */
+       ldswp.w r8, r12[0]
+       sub     r12, -4
+       lsr     r8, r8, r10
+       brne    .L_found
+
+       /* r9 = r9 - (32 - r10) = r9 + r10 - 32 */
+       add     r9, r10
+       sub     r9, 32
+       retle   r11
+
+       /* Main loop. offset must be word-aligned */
+1:     ldswp.w r8, r12[0]
+       cp.w    r8, 0
+       brne    .L_found
+       sub     r12, -4
+       sub     r9, 32
+       brgt    1b
+       retal   r11
+
 ENTRY(generic_find_next_zero_le_bit)
        lsr     r8, r10, 5
        sub     r9, r11, r10