Re: ${arch} setting

If gPXE returned struct cpuinfo_x86 as some hex bytes, would you be
willing to process the bytes server-side in order to determine features,
etc.?  - Shao

________________________________

From: Jason Robertson [mailto:[email protected]] 
Sent: Thursday, July 09, 2009 00:49
To: Miller, Shao
Subject: Re: [Etherboot-discuss] ${arch} setting

 

Hi,

Yes - we are trying to dynamically generate a chained gpxe script using
the architecture as an input into the generator.  So for example the
initial gpxe script will be downloaded from a URL including
http://....?arch=${arch <http://....?arch=$%7Barch> }.  This script then
generates a kernel and initrd loading script based on the architecture
and other properties which we then chain to.

 

________________________________

From: "Miller, Shao" <[email protected]>
To: Jason Robertson <[email protected]>
Cc: [email protected]
Sent: Tuesday, June 30, 2009 11:03:32 AM
Subject: Re: [Etherboot-discuss] ${arch} setting

Could you please describe your use case in a little more detail?  Are
you trying to tell a webserver about the client's architecture, by any
chance?  Are you trying to TFTP a file whose name includes the
architecture?  Sorry about the delay.  - Shao

________________________________

From: Jason Robertson [mailto:[email protected]] 
Sent: Tuesday, June 02, 2009 18:21
To: [email protected]
Subject: [Etherboot-discuss] ${arch} setting

 

Hi,

Is there a setting to easily obtain the architecture of the CPU in gpxe
(e.g. x86_64, x86 or ia32/ia32e) - something like that?  I looked
through the smbios stuff but the processor bits aren't really useful for
automation (it's a bitfield) and it seems older SMBios versions don't
include it.

I've been having to apply the below patch to each version, can we get
this added in a more "proper" way (I just hack it into settings.c)

/**
 * Parse and store value of arch setting
 *
 * @v settings      Settings block
 * @v setting       Setting to store
 * @v value     Formatted setting data
 * @ret rc      Return status code
 */
static int storef_arch ( struct settings *settings __unused,
             struct setting *setting __unused,
             const char *value __unused ) {
    return -ENOTSUP;
}

/**
 * Fetch and format value of arch setting
 *
 * @v settings      Settings block, or NULL to search all blocks
 * @v setting       Setting to fetch
 * @v buf       Buffer to contain formatted value
 * @v len       Length of buffer
 * @ret len     Length of formatted value, or negative error
 */
static int fetchf_arch ( struct settings *settings __unused,
                         struct setting *setting __unused, char *buf,
                         size_t len ) {
    struct cpuinfo_x86 cpuinfo;
    cpuinfo.amd_features = 0;
    cpuinfo.features = 0;
    get_cpuinfo(&cpuinfo);
    if (cpuinfo.amd_features & (1<<(X86_FEATURE_LM & 31))) {
        return snprintf(buf, len, "ia32e");
    }
    else {
        return snprintf(buf, len, "ia32");
    }
}

/** Arch setting type */
struct setting_type setting_type_arch __setting_type = {
    .name = "arch",
    .storef = storef_arch,
    .fetchf = fetchf_arch,
};

/** CPU arch (probably doesn't belong in this file) */
struct setting arch_setting __setting = {
    .name = "arch",
    .description = "CPU Architecture",
    .tag = 1,
    .type = &setting_type_arch,
};

------------------------------------------------------------------------------

_______________________________________________
Etherboot-discuss mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/etherboot-discuss