RE: Reading an entire cacheline

["Kim, Jong-Sung" <jsungkim@lge.com>]

Dear Mr. Seufer,

Thank you for your advice about directives. That's exactly what I meant. I
have confused them with push/pop style operations. Thanks.

Regards,
JS.

-----Original Message-----
From: Thiemo Seufer [mailto:ths@networkno.de] 
Sent: Wednesday, April 26, 2006 7:16 PM
To: Kim, Jong-Sung
Cc: linux-mips@linux-mips.org
Subject: Re: Reading an entire cacheline

Kim, Jong-Sung wrote:
> Hi all,
> 
> Please look at following codes:
> 
> save_flags(flags);
> cli();
> __asm__ __volatile__(
> 	"	.set	noreorder\n"
> 	"	.set	mips32\n"
> 	"2:	.set	mips3\n"
> 	"	cache	5, 0x00(%12)\n"
> 	"	.set	mips0\n"

Irrelevant sidemark:
.set mips0 resets to the original value, not to mips32. You probably want

	.set	push
	.set	noreorder
	.set 	mips32

	... <the whole code sequence>

	.set	pop

[snip]
> 	//"	bne	%0, %9, 2b\n"
> 	"	.set	mips0\n"
> 	"	.set	reorder"
> 	: "=r" (tag[1][way][0]), "=r" (datalo[1][way][0]),
> 	  "=r" (datahi[1][way][0]),
> 	  "=r" (tag[1][way][1]), "=r" (datalo[1][way][1]),
> 	  "=r" (datahi[1][way][1]),
> 	  "=r" (tag[1][way][2]), "=r" (datalo[1][way][2]),
> 	  "=r" (datahi[1][way][2]),
> 	  "=r" (tag[1][way][3]), "=r" (datalo[1][way][3]),
> 	  "=r" (datahi[1][way][3])
> 	: "r" (0x80000000 | (way << 14) | (line << 5))
> );

And this part may cause the problem you are seeing, I presume
datalo/datahi live in memory, and accesses of it change the dcache.

As Kevin mentioned, disassembling the binary might be helpful.


Thiemo