+
+ASM_PFX(ArmV7AllDataCachesOperation):
+ stmfd SP!,{r4-r12, LR}
+ mov R1, R0 @ Save Function call in R1
+ mrc p15, 1, R6, c0, c0, 1 @ Read CLIDR
+ ands R3, R6, #0x7000000 @ Mask out all but Level of Coherency (LoC)
+ mov R3, R3, LSR #23 @ Cache level value (naturally aligned)
+ beq L_Finished
+ mov R10, #0
+
+Loop1:
+ add R2, R10, R10, LSR #1 @ Work out 3xcachelevel
+ mov R12, R6, LSR R2 @ bottom 3 bits are the Cache type for this level
+ and R12, R12, #7 @ get those 3 bits alone
+ cmp R12, #2
+ blt L_Skip @ no cache or only instruction cache at this level
+ mcr p15, 2, R10, c0, c0, 0 @ write the Cache Size selection register (CSSELR) // OR in 1 for Instruction
+ isb @ ISB to sync the change to the CacheSizeID reg
+ mcr p15, 1, R12, c0, c0, 0 @ reads current Cache Size ID register (CCSIDR)
+ and R2, R12, #0x7 @ extract the line length field
+ and R2, R2, #4 @ add 4 for the line length offset (log2 16 bytes)
+ mov R4, #0x400
+ sub R4, R4, #1
+ ands R4, R4, R12, LSR #3 @ R4 is the max number on the way size (right aligned)
+ clz R5, R4 @ R5 is the bit position of the way size increment
+ mov R7, #0x00008000
+ sub R7, R7, #1
+ ands R7, R7, R12, LSR #13 @ R7 is the max number of the index size (right aligned)
+
+Loop2:
+ mov R9, R4 @ R9 working copy of the max way size (right aligned)
+
+Loop3:
+ orr R0, R10, R9, LSL R5 @ factor in the way number and cache number into R11
+ orr R0, R0, R7, LSL R2 @ factor in the index number
+
+ blx R1
+
+ subs R9, R9, #1 @ decrement the way number
+ bge Loop3
+ subs R7, R7, #1 @ decrement the index
+ bge Loop2
+L_Skip:
+ add R10, R10, #2 @ increment the cache number
+ cmp R3, R10
+ bgt Loop1
+
+L_Finished:
+ ldmfd SP!, {r4-r12, lr}
+ bx LR
+
+