Dear Uwe Kleine-König, > On Wed, Feb 29, 2012 at 08:45:27PM +0000, Russell King - ARM Linux wrote: > > On Wed, Feb 29, 2012 at 09:39:58PM +0100, Uwe Kleine-König wrote: > > > I'd bet your platform has cache support in the decompressor without > > > knowing which platform you use. I suggest commenting out > > > > > > bl cache_on > > > > > > in arch/arm/boot/compressed/head.S to see the difference. > > > > > > How do you build the uImage containing the zImage? If you use the > > > > > > in-kernel uImage target booting that usually means: > > > - move the zImage to ZRELADDR > > > - jump into zImage > > > - decompress zImage to somewhere else > > > - move decompressed image to ZRELADDR > > > - jump to ZRELADDR > > > > > > That is you have two relocations because the first location for sure > > > conflicts with the decompressed image. > > > > Actually, we do this slightly differently nowadays. Inside zImage: > > - if zImage location conflicts, move the decompressed data > > s/de// > > > and decompressor to another location > > > > - decompress zImage to ZRELADDR > > - jump to ZRELADDR > > > > That reduces the size required for copying. Of course, that copy can > > (as it's always been the case) be totally eliminated by ensuring that > > you load the zImage out of the way of the decompressed image. > > > > So, really, comparing a standard uImage produced by the standard kernel > > with gzipped Image is far from a fair comparison. And that's actually > > another argument for getting rid of the uImage target... it may make > > people think a bit about what they're doing rather than accepting > > whatever default location someone else chose for their kernel. > > I'm all in favour to remove the uImage target because back in 2007 we > already had a similar discussion[1]. (Back then I still thought that > improving the uImage support would be a good idea.) > > That said I think *in general* having support for U-Boot in the kernel > is fine because I think U-Boot is the bootloader used most. But if you > need some Kconfig settings or more than one Makefile target I think just > building an Image or zImage and doing the U-Boot wrapping without the > help of Linux' build system is preferable. I believe eventually everyone will converge to having this option enabled. Therefore this config option will just be always on and can be squashed away. > > Best regards > Uwe > > [1] http://thread.gmane.org/gmane.linux.ports.arm.kernel/36547/focus=36588 Best regards, Marek Vasut -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
