[coreboot] [PATCH] v3: print current and wanted LZMA scratchpad size
c-d.hailfinger.devel.2006 at gmx.net
Fri May 23 21:32:55 CEST 2008
On 23.05.2008 21:25, Myles Watson wrote:
> On Fri, May 23, 2008 at 1:22 PM, Carl-Daniel Hailfinger
> <c-d.hailfinger.devel.2006 at gmx.net> wrote:
>> Print current and wanted LZMA scratchpad size in the decompression
>> routine. That allows people to either adjust compression parameters
>> or scratchpad size.
>> Having a similar check during build time would be nice.
>> Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006 at gmx.net>
>> Index: LinuxBIOSv3-tmp/lib/lzma.c
>> --- LinuxBIOSv3-tmp/lib/lzma.c (Revision 682)
>> +++ LinuxBIOSv3-tmp/lib/lzma.c (Arbeitskopie)
>> @@ -14,6 +14,7 @@
>> #include "string.h"
>> #include "console.h"
>> +#define LZMA_SCRATCHPAD_SIZE 15980
> What's the reason for 15980? What's the downside to increasing it further?
It's the value I picked during OLPC early bringup, based on compression
efficiency measurements correlated with stack requirements. It seemed to
be the sweet spot on Geode back then. Besides that, v3 relies on the
stack not to outgrow 32k IIRC, otherwise stack and printk buffer will
corrupt each other.
Right now the patch is a no-op except for the better error message.
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