On Wed, Jan 12, 2011 at 12:27 PM, Lei Wen adrian.wenl@gmail.com wrote:
Hi Albert,
On Wed, Jan 12, 2011 at 3:53 AM, Albert ARIBAUD albert.aribaud@free.fr wrote:
Hi,
Le 11/01/2011 16:40, Lei Wen a écrit :
flush_cache function should only be called when the dcache is on. And original flush method for arm926ejs seems don't work, replace it with new version.
Test on Marvell Pantheon pxa920 board with usb ether function.
Signed-off-by: Lei Wenleiwen@marvell.com
arch/arm/lib/cache.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c index 30686fe..b8d5eee 100644 --- a/arch/arm/lib/cache.c +++ b/arch/arm/lib/cache.c @@ -27,16 +27,16 @@
void flush_cache (unsigned long dummy1, unsigned long dummy2) {
- if (!dcache_status())
- return;
#if defined(CONFIG_OMAP2420) || defined(CONFIG_ARM1136) void arm1136_cache_flush(void);
arm1136_cache_flush(); #endif #ifdef CONFIG_ARM926EJS
- /* test and clean, page 2-23 of arm926ejs manual */
- asm("0: mrc p15, 0, r15, c7, c10, 3\n\t" "bne 0b\n" : : : "memory");
- /* disable write buffer as well (page 2-22) */
- asm("mcr p15, 0, %0, c7, c10, 4" : : "r" (0));
- /* clean& invalidate all D cache */
- asm("mcr p15, 0, %0, c7, c14, 0" : : "r" (0));
ARM's ARM926EJ-S r0p4/r0p5 TRM does not define "... c7, c14, 0". Where did you find this exact cp15 instruction?
My mistake... Pantheon board's sheeva core modify the standard cp15 op code a bit... With one opcode, it could invalidate and clean the dcache all.
So could I modify the original patch like below? asm("mcr p15, 0, %0, c7, c6, 0" : : "r" (0)); This would only invalidate all dcache. Since current dcache enable is just write-through, I think it is safe to just do the invalidate operation.
This also could works for my board.
I take my words back... I forget to open the dcache... After dcache is on, the usb tftp still cannot works... Seems still do the clean cache operation...
Best regards, Lei