From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: [PATCH 1/6] ARM: Add inline function smp_cpu() for early init testing Date: Thu, 2 Sep 2010 12:26:59 -0700 Message-ID: <20100902192659.GW11597@atomide.com> References: <4C6CFBAF.6020407@canonical.com> <20100819095705.GU12184@atomide.com> <20100819102025.GA32151@n2100.arm.linux.org.uk> <20100820120622.GL25742@atomide.com> <20100830225527.GC11597@atomide.com> <20100902133637.GJ26319@n2100.arm.linux.org.uk> <20100902161659.GJ11597@atomide.com> <20100902161846.GK11597@atomide.com> <20100902170830.GW26319@n2100.arm.linux.org.uk> <20100902174244.GU11597@atomide.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="jL2BoiuKMElzg3CS" Return-path: Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:54135 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756182Ab0IBT1L (ORCPT ); Thu, 2 Sep 2010 15:27:11 -0400 Content-Disposition: inline In-Reply-To: <20100902174244.GU11597@atomide.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Russell King - ARM Linux Cc: linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Bryan Wu , Will Deacon --jL2BoiuKMElzg3CS Content-Type: text/plain; charset=us-ascii Content-Disposition: inline * Tony Lindgren [100902 10:35]: > * Russell King - ARM Linux [100902 10:00]: > > On Thu, Sep 02, 2010 at 09:18:47AM -0700, Tony Lindgren wrote: > > > > > --- a/arch/arm/include/asm/smp_plat.h > > > +++ b/arch/arm/include/asm/smp_plat.h > > > @@ -39,4 +39,20 @@ static inline int cache_ops_need_broadcast(void) > > > #define UP(instr...) _str(instr) > > > #endif > > > > > > +static inline int smp_on_up(void) > > > +{ > > > +#ifdef CONFIG_SMP_ON_UP > > > + int smp_on_up; > > > + > > > + asm( \ > > > + SMP(mov %0, #0) \ > > > + UP(mov %0, #1) \ > > > + : "=r" (smp_on_up)); > > > + > > > + return smp_on_up; > > > +#else > > > + return 0; > > > +#endif > > > > I think this is the wrong approach - rather than a function which tells us > > just if we are a SMP kernel running on UP, why not something which returns > > whether we're running on SMP and use that to eliminate some of these ifdefs? > > Sure. Will has something like this in his patches: > > static inline int cpu_is_part_of_mp_system(void) > { > u32 mpidr; > asm volatile("mrc p15, 0, %0, c0, c0, 5" : "=r" (mpidr)); > return (mpidr >> 31) ? !(mpidr >> 30) : 0; > } > > BTW, so far looks like we should only need this during init to set up things. Here's this one updated to replace smp_cpu() instead of smp_on_up(). Tony --jL2BoiuKMElzg3CS Content-Type: text/x-diff; charset=us-ascii Content-Disposition: inline; filename="smp-cpu.patch" From: Tony Lindgren Date: Mon, 30 Aug 2010 14:00:54 -0700 Subject: [PATCH] ARM: Add inline function smp_cpu() for early init testing Add inline function smp_cpu() for early init checks, and change build_mem_type_table to use it. Inline function copied from cpu_is_part_of_mp_system() by Will Deacon . Signed-off-by: Tony Lindgren diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h index 8db3512..82bc488 100644 --- a/arch/arm/include/asm/smp_plat.h +++ b/arch/arm/include/asm/smp_plat.h @@ -39,4 +39,11 @@ static inline int cache_ops_need_broadcast(void) #define UP(instr...) _str(instr) #endif +static inline int smp_cpu(void) +{ + u32 mpidr; + asm volatile("mrc p15, 0, %0, c0, c0, 5" : "=r" (mpidr)); + return (mpidr >> 31) ? !(mpidr >> 30) : 0; +} + #endif diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index 6e1c4f6..2bfaefd 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -430,15 +430,17 @@ static void __init build_mem_type_table(void) /* * Mark memory with the "shared" attribute for SMP systems */ - user_pgprot |= L_PTE_SHARED; - kern_pgprot |= L_PTE_SHARED; - vecs_pgprot |= L_PTE_SHARED; - mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S; - mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED; - mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S; - mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED; - mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S; - mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S; + if (smp_cpu()) { + user_pgprot |= L_PTE_SHARED; + kern_pgprot |= L_PTE_SHARED; + vecs_pgprot |= L_PTE_SHARED; + mem_types[MT_DEVICE_WC].prot_sect |= PMD_SECT_S; + mem_types[MT_DEVICE_WC].prot_pte |= L_PTE_SHARED; + mem_types[MT_DEVICE_CACHED].prot_sect |= PMD_SECT_S; + mem_types[MT_DEVICE_CACHED].prot_pte |= L_PTE_SHARED; + mem_types[MT_MEMORY].prot_sect |= PMD_SECT_S; + mem_types[MT_MEMORY_NONCACHED].prot_sect |= PMD_SECT_S; + } #endif } --jL2BoiuKMElzg3CS--