From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann E. MORIN Date: Fri, 4 Apr 2014 00:12:15 +0200 Subject: [Buildroot] [PATCH 02/11] arch: MIPS: Add config option BR2_GCC_TARGET_TUNE In-Reply-To: <533DD7B6.8080009@crapouillou.net> References: <1396558881-29631-1-git-send-email-paul@crapouillou.net> <1396558881-29631-2-git-send-email-paul@crapouillou.net> <20140403211925.GC17328@free.fr> <533DD7B6.8080009@crapouillou.net> Message-ID: <20140403221215.GA25471@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Paul, All, On 2014-04-03 23:50 +0200, Paul Cercueil spake thusly: > This patch would pass the same value to --with-arch and --with-tune, unless > you define a different value for BR2_GCC_TARGET_TUNE in your defconfig. I see what you expect, but since BR2_GCC_TARGET_TUNE is a prompt-less option, setting it in a defconfig will be overriden when you use that defconfig. For example: $ cat defconfig BR2_MIPS=y BR2_GCC_TARGET_ARCH="FOO-YEM" $ make BR2_DEFCONFIG=$(pwd)/defconfig defconfig [...] $ grep FOO .config [empty, nada, zilch] So, even if you set it in your defconfig, BR2_GCC_TARGET_ARCH is lost. Ditto for BR2_GCC_TARGET_TUNE. > We > use that for the Ingenic jz4740 processor, which is a mips32 processor but > running better the code tuned for mips32r2. Oh, I see. But that's not gonna happen with this code, I'm afraid. Can you double-check that it is indeed working for you? Because if it does, we have a really big bug in Kconfig (Oh, no, not one more...) Regards, Yann E. MORIN. > On 03/04/2014 23:19, Yann E. MORIN wrote: > >Paul, All, > > > >On 2014-04-03 23:01 +0200, Paul Cercueil spake thusly: > >>This option is actually already used in GCC's package. > >> > >>This allows to optimize the toolchain for a specific MIPS processor > >>while supporting more than one family of processors. > >Is that really needed? man gcc says: > > > > When this option is not used, GCC optimizes for the processor > > specified by -march. > > > >Since this patch would pass the same value to --with-arch and > >--with-tune, and since this is the default of gcc, is it really > >needed? > > > >Neither ACKing nor NAKing this patch. Can you explain a bit more why we > >would want that, given the above explanations? > > > >Regards, > >Yann E. MORIN. > > > >>Signed-Off-By: Paul Cercueil > >>--- > >> arch/Config.in.mips | 10 ++++++++++ > >> 1 file changed, 10 insertions(+) > >> > >>diff --git a/arch/Config.in.mips b/arch/Config.in.mips > >>index 20951e0..e4160a2 100644 > >>--- a/arch/Config.in.mips > >>+++ b/arch/Config.in.mips > >>@@ -83,6 +83,16 @@ config BR2_GCC_TARGET_ARCH > >> default "mips64" if BR2_mips_64 > >> default "mips64r2" if BR2_mips_64r2 > >>+config BR2_GCC_TARGET_TUNE > >>+ default "mips1" if BR2_mips_1 > >>+ default "mips2" if BR2_mips_2 > >>+ default "mips3" if BR2_mips_3 > >>+ default "mips4" if BR2_mips_4 > >>+ default "mips32" if BR2_mips_32 > >>+ default "mips32r2" if BR2_mips_32r2 > >>+ default "mips64" if BR2_mips_64 > >>+ default "mips64r2" if BR2_mips_64r2 > >>+ > >> config BR2_MIPS_OABI32 > >> bool > >> default y if BR2_mips || BR2_mipsel > >>-- > >>1.9.0 > >> > >>_______________________________________________ > >>buildroot mailing list > >>buildroot at busybox.net > >>http://lists.busybox.net/mailman/listinfo/buildroot > -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------'