On Tue, Jan 17, 2012 at 8:47 PM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > On Tue, Jan 17, 2012 at 04:27:21PM +0000, Catalin Marinas wrote: >> Anyway, the first step is this API provided by the secure firmware. >> Since such API may need to be called before the MMU is initialised, >> Linux would need to have knowledge of the platform type early on. Having >> some platform hook (asm macro) to call early on wouldn't work with the >> single zImage configuration. Stack space is not an issue as we already >> have one for ARMv7 for D-cache flushing (XIP kernels would work but they >> aren't that many). > > It _is_ a problem. How much stack space would these undefined platform > specific functions require? 16 words? 32 words? A page? Where does > this memory come from? The .data section, or are we going to stuff it > into what is supposed to be the read-only text section? Stack requirement is limited to saving and restoring the processor registers. There is no additional need. If this is an issue, we can also use SRAM as a stack for this operation. Regards Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
