Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751687Ab2K1GF5 (ORCPT ); Wed, 28 Nov 2012 01:05:57 -0500 Received: from mail-pb0-f46.google.com ([209.85.160.46]:60027 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751062Ab2K1GFz (ORCPT ); Wed, 28 Nov 2012 01:05:55 -0500 Date: Tue, 27 Nov 2012 22:05:53 -0800 From: Olof Johansson To: Kukjin Kim Cc: "'Doug Anderson'" , "'Arnd Bergmann'" , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, "'Russell King'" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] ARM: EXYNOS: Avoid early use of of_machine_is_compatible() Message-ID: <20121128060553.GA18166@quad.lixom.net> References: <1354045994-8977-1-git-send-email-dianders@chromium.org> <50B53E37.40303@samsung.com> <18d701cdcd28$74198d70$5c4ca850$%kim@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <18d701cdcd28$74198d70$5c4ca850$%kim@samsung.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6076 Lines: 168 On Wed, Nov 28, 2012 at 02:23:09PM +0900, Kukjin Kim wrote: > Olof Johansson wrote: > > > > On Tue, Nov 27, 2012 at 2:27 PM, Kukjin Kim wrote: > > > On 11/28/12 07:11, Olof Johansson wrote: > > >> > > >> On Tue, Nov 27, 2012 at 11:53 AM, Doug Anderson > > >> wrote: > > >>> > > >>> The recent commit "ARM: EXYNOS: add support for EXYNOS5440 SoC" broke > > >>> support for exynos5250 because of_machine_is_compatible() was used too > > >>> early in the boot process. It also probably meant that the exynos5440 > > >>> failed to use the proper iotable. Switch to use > > >>> of_flat_dt_is_compatible() in both of these cases. > > >>> > > >>> The failure I was seeing in exynos5250 because of this was: > > >>> Division by zero in kernel. > > >>> [<80015ed4>] (unwind_backtrace+0x0/0xec) from [<8045c7a4>] > > >>> (dump_stack+0x20/0x24) > > >>> [<8045c7a4>] (dump_stack+0x20/0x24) from [<80012990>] > > >>> (__div0+0x20/0x28) > > >>> [<80012990>] (__div0+0x20/0x28) from [<8021ab04>] > (Ldiv0_64+0x8/0x18) > > >>> [<8021ab04>] (Ldiv0_64+0x8/0x18) from [<80068560>] > > >>> (__clocksource_updatefreq_scale+0x54/0x134) > > >>> [<80068560>] (__clocksource_updatefreq_scale+0x54/0x134) from > > >>> [<8006865c>] (__clocksource_register_scale+0x1c/0x54) > > >>> [<8006865c>] (__clocksource_register_scale+0x1c/0x54) from > > >>> [<80612a18>] (exynos_timer_init+0x100/0x1e8) > > >>> [<80612a18>] (exynos_timer_init+0x100/0x1e8) from [<8060d184>] > > >>> (time_init+0x28/0x38) > > >>> [<8060d184>] (time_init+0x28/0x38) from [<8060a754>] > > >>> (start_kernel+0x1e0/0x3c8) > > >>> [<8060a754>] (start_kernel+0x1e0/0x3c8) from [<40008078>] > > (0x40008078) > > >>> > > >>> Signed-off-by: Doug Anderson > > >> > > >> > > >> Thanks Doug. > > >> > > >> Kukjin, I'll apply this directly on top of the previous branch in > > >> arm-soc, if that's OK with you. > > >> > > > Sure, go ahead with my ack if you want, > > > > > > Acked-by: Kukjin Kim > > > > > > Note, actually there was a fix which uses soc_is_exynos5440() in my > > local > > > :-) I'm not sure which one is better at this moment, but I'm OK on this. > > > > Ok, applied. Thanks all. > > > Olof, just note, happens build error with exynos4_defconfig because of > non-DT. Ick, thanks for catching that. > > Following can resolve it or we should create null function for > of_get_flat_dt_root() and of_flat_dt_is_compatible()... > > 8<--------------------------------------- > From: Kukjin Kim > Subject: ARM: EXYNOS: fix a build error with non-DT for exynos4 > > This fixes following in case of non-DT: > arch/arm/mach-exynos/common.c: In function 'exynos_init_io': > arch/arm/mach-exynos/common.c:339: error: implicit declaration of function > 'of_get_flat_dt_root' > arch/arm/mach-exynos/common.c:342: error: implicit declaration of function > 'of_flat_dt_is_compatible' > make[1]: *** [arch/arm/mach-exynos/common.o] Error 1 > > Signed-off-by: Kukjin Kim > --- > diff --git a/arch/arm/mach-exynos/common.c b/arch/arm/mach-exynos/common.c > index b919f5f..2110091 100644 > --- a/arch/arm/mach-exynos/common.c > +++ b/arch/arm/mach-exynos/common.c > @@ -336,12 +336,14 @@ void __init exynos_init_late(void) > > void __init exynos_init_io(struct map_desc *mach_desc, int size) > { > +#ifdef CONFIG_OF > unsigned long root = of_get_flat_dt_root(); > > /* initialize the io descriptors we need for initialization */ > if (of_flat_dt_is_compatible(root, "samsung,exynos5440")) > iotable_init(exynos5440_iodesc, > ARRAY_SIZE(exynos5440_iodesc)); > else > +#endif > iotable_init(exynos_iodesc, ARRAY_SIZE(exynos_iodesc)); I really don't like splitting an if/else with an ifdef like this, it's fragile code and can be hard to follow. There's also a second build error with exynos_defconfig in the exynos5-dt.c board file due to a missing include. Teaches me to just apply patches without trying to build. :( I'll squash this into Doug's original patch, if that's OK? diff --git a/arch/arm/mach-exynos/common.c b/arch/arm/mach-exynos/common.c index 796e0c9..77e7c5b 100644 --- a/arch/arm/mach-exynos/common.c +++ b/arch/arm/mach-exynos/common.c @@ -122,6 +122,7 @@ static struct map_desc exynos_iodesc[] __initdata = { }, }; +#ifdef CONFIG_ARCH_EXYNOS5 static struct map_desc exynos5440_iodesc[] __initdata = { { .virtual = (unsigned long)S5P_VA_CHIPID, @@ -130,6 +131,7 @@ static struct map_desc exynos5440_iodesc[] __initdata = { .type = MT_DEVICE, }, }; +#endif static struct map_desc exynos4_iodesc[] __initdata = { { @@ -347,13 +349,19 @@ void __init exynos_init_late(void) void __init exynos_init_io(struct map_desc *mach_desc, int size) { + struct map_desc *iodesc = exynos_iodesc; + int iodesc_sz = ARRAY_SIZE(exynos_iodesc); +#ifdef CONFIG_OF unsigned long root = of_get_flat_dt_root(); /* initialize the io descriptors we need for initialization */ - if (of_flat_dt_is_compatible(root, "samsung,exynos5440")) - iotable_init(exynos5440_iodesc, ARRAY_SIZE(exynos5440_iodesc)); - else - iotable_init(exynos_iodesc, ARRAY_SIZE(exynos_iodesc)); + if (of_flat_dt_is_compatible(root, "samsung,exynos5440")) { + iodesc = exynos5440_iodesc; + iodesc_sz = ARRAY_SIZE(exynos5440_iodesc); + } +#endif + + iotable_init(iodesc, iodesc_sz); if (mach_desc) iotable_init(mach_desc, size); diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c index 2a75624..f1326be 100644 --- a/arch/arm/mach-exynos/mach-exynos5-dt.c +++ b/arch/arm/mach-exynos/mach-exynos5-dt.c @@ -10,6 +10,7 @@ */ #include +#include #include #include -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/