>-----Original Message----- >From: Andi Kleen [mailto:[EMAIL PROTECTED] >Subject: Re: [PATCH 5/5] x86_64 EFI support -v3: EFI document >> The needed code changing is minimal. In fact, I can boot 32bit Linux >> kernel on my x86_64 EFI machine. With setup as follow: >> >> 1. Apply the efi-fb.patch >Just for the frame buffer, right?
Yes. >> 2. make efi fb driver not depend on EFI >> 3. configure kernel as follow: >> a. CONFIG_EFI is turned off >> b. CONFIG_FB_EFI is turned on > >Hmm, how does the 32bit kernel know where the e820 map is passed then? >With CONFIG_EFI turned off it will just ask the real mode BIOS I think >and I doubt elilo simulates that. I have not tested elilo. I use another x86_64 EFI boot loader (it will be released soon), but elilo works in the same way, and I will test elilo later. The 16bit entry of kernel (arch/(i386|x86_64)/boot/setup.S) is not used by elilo. Instead, elilo collects the needed information defined in include/asm-x86_64/bootsetup.h itself, and passes it to kernel 32bit entry (arch/(i386|x86_64)/boot/compressed/head.S). For E820 map, the elilo converts the EFI memory map to E820 map in "boot parameters memory" which is copied to "boot_params" or "x86_boot_params" by Linux kernel later. >Or did you apply more patches? No, just the frame buffer patch. Best Regards, Huang Ying - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
