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OMAP3: PM: Update clean_l2 to use v7_flush_dcache_all

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Analysis in TI kernel with ETM showed that using cache mapped flush
in kernel instead of SO mapped flush cost drops by 65% (3.39mS down
to 1.17mS) for clean_l2 which is used during sleep sequences.
Overall:
	- speed up
	- unfortunately there isn't a good alternative flush method today
	- code reduction and less maintenance and potential bug in
	  unmaintained code

This also fixes the bug with the clean_l2 function usage.

Reported-by: Tony Lindgren <tony@atomide.com>

Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Tony Lindgren <tony@atomide.com>

Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Jean Pihet <j-pihet@ti.com>

[nm@ti.com: ported rkw's proposal to 2.6.37-rc2]
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This commit is contained in:
Richard Woodruff 2010-12-20 14:05:03 -06:00 committed by Kevin Hilman
parent 1cbbe37ac5
commit 0bd4053536
1 changed files with 14 additions and 66 deletions
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80
arch/arm/mach-omap2/sleep34xx.S
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@ -520,72 +520,18 @@ clean_caches:
cmp r9, #1 /* Check whether L2 inval is required or not*/
bne skip_l2_inval
clean_l2:
/* read clidr */
mrc p15, 1, r0, c0, c0, 1
/* extract loc from clidr */
ands r3, r0, #0x7000000
/* left align loc bit field */
mov r3, r3, lsr #23
/* if loc is 0, then no need to clean */
beq finished
/* start clean at cache level 0 */
mov r10, #0
loop1:
/* work out 3x current cache level */
add r2, r10, r10, lsr #1
/* extract cache type bits from clidr*/
mov r1, r0, lsr r2
/* mask of the bits for current cache only */
and r1, r1, #7
/* see what cache we have at this level */
cmp r1, #2
/* skip if no cache, or just i-cache */
blt skip
/* select current cache level in cssr */
mcr p15, 2, r10, c0, c0, 0
/* isb to sych the new cssr&csidr */
isb
/* read the new csidr */
mrc p15, 1, r1, c0, c0, 0
/* extract the length of the cache lines */
and r2, r1, #7
/* add 4 (line length offset) */
add r2, r2, #4
ldr r4, assoc_mask
/* find maximum number on the way size */
ands r4, r4, r1, lsr #3
/* find bit position of way size increment */
clz r5, r4
ldr r7, numset_mask
/* extract max number of the index size*/
ands r7, r7, r1, lsr #13
loop2:
mov r9, r4
/* create working copy of max way size*/
loop3:
/* factor way and cache number into r11 */
orr r11, r10, r9, lsl r5
/* factor index number into r11 */
orr r11, r11, r7, lsl r2
/*clean & invalidate by set/way */
mcr p15, 0, r11, c7, c10, 2
/* decrement the way*/
subs r9, r9, #1
bge loop3
/*decrement the index */
subs r7, r7, #1
bge loop2
skip:
add r10, r10, #2
/* increment cache number */
cmp r3, r10
bgt loop1
finished:
/*swith back to cache level 0 */
mov r10, #0
/* select current cache level in cssr */
mcr p15, 2, r10, c0, c0, 0
isb
/*
* Jump out to kernel flush routine
* - reuse that code is better
* - it executes in a cached space so is faster than refetch per-block
* - should be faster and will change with kernel
* - 'might' have to copy address, load and jump to it
* - lr is used since we are running in SRAM currently.
*/
ldr r1, kernel_flush
mov lr, pc
bx r1
skip_l2_inval:
/* Data memory barrier and Data sync barrier */
mov r1, #0
@ -668,5 +614,7 @@ cache_pred_disable_mask:
.word 0xFFFFE7FB
control_stat:
.word CONTROL_STAT
kernel_flush:
.word v7_flush_dcache_all
ENTRY(omap34xx_cpu_suspend_sz)
.word . - omap34xx_cpu_suspend