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[Bug 1000060] New: Memory above 64MB is not available as heap storage (i386)


http://bugs.ecos.sourceware.org/show_bug.cgi?id=1000060

           Summary: Memory above 64MB is not available as heap storage
                    (i386)
           Product: eCos
           Version: 2.0
          Platform: pc (i386 PC target)
        OS/Version: HostOS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: normal
         Component: HAL
        AssignedTo: jifl@ecoscentric.com
        ReportedBy: Kevin_Lemay@agilent.com
         QAContact: ecos-bugs@sources.redhat.com


The pcmb_misc.c uses calls to read the extended memory size from CMOS. This
interface limits the visable memory size to 64MB. There are new BIOS int 15
calls which may be used to determine to proper amount of extended memory in a
system.

This problem is complicated. The BIOS calls must be made by the boot monitor
before the processor is switched into protected mode. It appears that pcmb.inc
does call the old 88h function.

If a RAM application is loaded by redboot, then a function must be called to
retrieve the value from redboot since these routines cannot be called in
protected mode. Once protected mode is entered, you cannot re-enter real mode
without reseting the processor.

The e820h routine should be tried first, followed by e801h and then 88h.

I did code the assembler for this, but I was unable to determine how to pass
these values up to the RAM instantiation.

I am currently using a modified pcmb_misc.c that walks the memory to determine
the proper size when the CMOS returns 64MB (a kludge at best, but it works).



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