From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Herrenschmidt To: Gabriel Paubert , linuxppc-dev Subject: Re: Platform configuration (was: Re: CONFIG_PPC != Mac) Date: Thu, 31 Aug 2000 18:22:09 +0200 Message-Id: <20000831162209.31786@mailhost.mipsys.com> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: >First, kernel compile times are only fairly large after a big update, when >I do `make dep clean zImage'. Second, the proportion of time spend in the >specific PPC code (mostly arch/ppc and drivers/macintosh) is rather small. >Third, building a minimal kernel image for each machine would involve a >ton (and that's an undrestatement) of kernel options: CONFIG_INTC_8259, >CONFIG_INTC_POWERMAC, CONFIG_INTC_OPENPIC and others for the interrupt >controllers, half a dozen or so CONFIG_RTC types, same for CONFIG_NVRAM >and a few other things I surely forget. The only reasonable solution is to >aim for the smallest runtime kernel image. Well, an easy first step is to have those per-machine cumulative compile options so you can choose pmac only, pmac+chrp, etc... That's only a few more config stuffs (CONFIG_PPC_PMAC, CONFIG_PPC_PREP, etc...), the core code wouldn't need to change. We can even optimize the various if (_machine == xxxx) using maros that get resolved to a constant when only one machine type is compiled in. Ben. ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/