From mboxrd@z Thu Jan 1 00:00:00 1970 From: dave.martin@linaro.org (Dave Martin) Date: Tue, 25 Jun 2013 15:13:32 +0100 Subject: [PATCH] ARM: keystone: remove hand-coded smc instruction In-Reply-To: <51C4D9B7.5010109@ti.com> References: <201306212228.29717.arnd@arndb.de> <201306212313.16771.arnd@arndb.de> <51C4C3B4.2050508@ti.com> <201306212341.08579.arnd@arndb.de> <51C4D9B7.5010109@ti.com> Message-ID: <20130625141332.GC2327@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Jun 21, 2013 at 06:54:47PM -0400, Santosh Shilimkar wrote: > On Friday 21 June 2013 05:41 PM, Arnd Bergmann wrote: > > On Friday 21 June 2013, Santosh Shilimkar wrote: > >>> > >> I was curious how you will fix that for a c file. > >> Just to be clear, I was planning to do that in 3.11-rcx/3.12 > >> time. Let me know if it needs to be done earlier than that. > > > > It breaks randconfig builds on arm-soc at the moment, so I'd > > like the fix as early as possible for 3.11. > > > Ok, fix is at end of the email. Let me know if it makes > to pass both the builds now. I have build and boot tested > both ARM and THUMB2 builds on Keystone board. > > Regards, > Santosh > > From 05d6a5b6cad624fb3791e8c1f8eb7c774f0790d9 Mon Sep 17 00:00:00 2001 > From: Santosh Shilimkar > Date: Fri, 21 Jun 2013 18:35:32 -0400 > Subject: [PATCH] ARM: keystone: Move CPU bringup code to dedicated asm file > > Because of inline asm usage in platsmp.c, smc instruction > creates build failure for ARM V6+V7 build where as using instruction > encoding for smc breaks the thumb2 build. > > So move the code snippet to separate asm file and mark > it with 'armv7-a$(plus_sec)' to avoid any build issues. > > Cc: Arnd Bergmann > > Signed-off-by: Santosh Shilimkar > --- > arch/arm/mach-keystone/Makefile | 6 +++++- > arch/arm/mach-keystone/keystone.h | 6 ++++++ > arch/arm/mach-keystone/platsmp.c | 15 +++------------ > arch/arm/mach-keystone/smc.S | 29 +++++++++++++++++++++++++++++ > 4 files changed, 43 insertions(+), 13 deletions(-) > create mode 100644 arch/arm/mach-keystone/smc.S > > diff --git a/arch/arm/mach-keystone/Makefile b/arch/arm/mach-keystone/Makefile > index 3f6b8ab..ddc52b0 100644 > --- a/arch/arm/mach-keystone/Makefile > +++ b/arch/arm/mach-keystone/Makefile > @@ -1,2 +1,6 @@ > -obj-y := keystone.o > +obj-y := keystone.o smc.o > + > +plus_sec := $(call as-instr,.arch_extension sec,+sec) > +AFLAGS_smc.o :=-Wa,-march=armv7-a$(plus_sec) > + > obj-$(CONFIG_SMP) += platsmp.o > diff --git a/arch/arm/mach-keystone/keystone.h b/arch/arm/mach-keystone/keystone.h > index 43a1b47..60bef9d 100644 > --- a/arch/arm/mach-keystone/keystone.h > +++ b/arch/arm/mach-keystone/keystone.h > @@ -11,7 +11,13 @@ > #ifndef __KEYSTONE_H__ > #define __KEYSTONE_H__ > > +#define KEYSTONE_MON_CPU_UP_IDX 0x00 > + > +#ifndef __ASSEMBLER__ > + > extern struct smp_operations keystone_smp_ops; > extern void secondary_startup(void); > +extern u32 keystone_cpu_smc(u32 command, u32 cpu, u32 addr); > > +#endif /* __ASSEMBLER__ */ > #endif /* __KEYSTONE_H__ */ > diff --git a/arch/arm/mach-keystone/platsmp.c b/arch/arm/mach-keystone/platsmp.c > index 630ab3b..1d4181e 100644 > --- a/arch/arm/mach-keystone/platsmp.c > +++ b/arch/arm/mach-keystone/platsmp.c > @@ -30,18 +30,9 @@ static int __cpuinit keystone_smp_boot_secondary(unsigned int cpu, > pr_debug("keystone-smp: booting cpu %d, vector %08lx\n", > cpu, start); > > - asm volatile ( > - "mov r0, #0\n" /* power on cmd */ > - "mov r1, %1\n" /* cpu */ > - "mov r2, %2\n" /* start */ > - ".inst 0xe1600070\n" /* smc #0 */ > - "mov %0, r0\n" > - : "=r" (error) > - : "r"(cpu), "r"(start) > - : "cc", "r0", "r1", "r2", "memory" > - ); > - > - pr_debug("keystone-smp: monitor returned %d\n", error); > + error = keystone_cpu_smc(KEYSTONE_MON_CPU_UP_IDX, cpu, start); > + if (error) > + pr_err("CPU %d bringup failed with %d\n", cpu, error); > > return error; > } > diff --git a/arch/arm/mach-keystone/smc.S b/arch/arm/mach-keystone/smc.S > new file mode 100644 > index 0000000..9b9e4f7 > --- /dev/null > +++ b/arch/arm/mach-keystone/smc.S > @@ -0,0 +1,29 @@ > +/* > + * Keystone Secure APIs > + * > + * Copyright (C) 2013 Texas Instruments, Inc. > + * Santosh Shilimkar > + * > + * This program is free software,you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#include > + > +/** > + * u32 keystone_cpu_smc(u32 command, u32 cpu, u32 addr) > + * > + * Low level CPU monitor API > + * @command: Monitor command. > + * @cpu: CPU Number > + * @addr: Kernel jump address for boot CPU > + * > + * Return: Non zero value on failure > + */ Oops, looks like I missed the final mail on this thread. Ignore my previous mail. I still think it would be a good idea to try to consolidate all these trivial SMC wrappers, but this remains debatable. Anyway, this looks like it should work, except: > +ENTRY(keystone_cpu_smc) > + stmfd sp!, {r4-r12, lr} > + smc #0 > + dsb What's this DSB for? (You didn't have it in the inline asm version) > + ldmfd sp!, {r4-r12, pc} > +ENDPROC(keystone_cpu_smc) r12 is caller-save btw; you don't need to preserve it. Cheers ---Dave