From 593f4a788e5d09e9f00182561437461b0b564de4 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Wed, 16 Jul 2008 19:15:30 +0100 Subject: x86: APIC: remove apic_write_around(); use alternatives Use alternatives to select the workaround for the 11AP Pentium erratum for the affected steppings on the fly rather than build time. Remove the X86_GOOD_APIC configuration option and replace all the calls to apic_write_around() with plain apic_write(), protecting accesses to the ESR as appropriate due to the 3AP Pentium erratum. Remove apic_read_around() and all its invocations altogether as not needed. Remove apic_write_atomic() and all its implementing backends. The use of ASM_OUTPUT2() is not strictly needed for input constraints, but I have used it for readability's sake. I had the feeling no one else was brave enough to do it, so I went ahead and here it is. Verified by checking the generated assembly and tested with both a 32-bit and a 64-bit configuration, also with the 11AP "feature" forced on and verified with gdb on /proc/kcore to work as expected (as an 11AP machines are quite hard to get hands on these days). Some script complained about the use of "volatile", but apic_write() needs it for the same reason and is effectively a replacement for writel(), so I have disregarded it. I am not sure what the policy wrt defconfig files is, they are generated and there is risk of a conflict resulting from an unrelated change, so I have left changes to them out. The option will get removed from them at the next run. Some testing with machines other than mine will be needed to avoid some stupid mistake, but despite its volume, the change is not really that intrusive, so I am fairly confident that because it works for me, it will everywhere. Signed-off-by: Maciej W. Rozycki Signed-off-by: Ingo Molnar --- include/asm-x86/apic.h | 24 +++++++----------------- 1 file changed, 7 insertions(+), 17 deletions(-) (limited to 'include/asm-x86/apic.h') diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h index 4e2c1e517f0..ea866baccef 100644 --- a/include/asm-x86/apic.h +++ b/include/asm-x86/apic.h @@ -3,6 +3,8 @@ #include #include + +#include #include #include #include @@ -48,7 +50,6 @@ extern int disable_apic; #include #else #define apic_write native_apic_write -#define apic_write_atomic native_apic_write_atomic #define apic_read native_apic_read #define setup_boot_clock setup_boot_APIC_clock #define setup_secondary_clock setup_secondary_APIC_clock @@ -58,12 +59,11 @@ extern int is_vsmp_box(void); static inline void native_apic_write(unsigned long reg, u32 v) { - *((volatile u32 *)(APIC_BASE + reg)) = v; -} + volatile u32 *addr = (volatile u32 *)(APIC_BASE + reg); -static inline void native_apic_write_atomic(unsigned long reg, u32 v) -{ - (void)xchg((u32 *)(APIC_BASE + reg), v); + alternative_io("movl %0, %1", "xchgl %0, %1", X86_FEATURE_11AP, + ASM_OUTPUT2("=r" (v), "=m" (*addr)), + ASM_OUTPUT2("0" (v), "m" (*addr))); } static inline u32 native_apic_read(unsigned long reg) @@ -75,16 +75,6 @@ extern void apic_wait_icr_idle(void); extern u32 safe_apic_wait_icr_idle(void); extern int get_physical_broadcast(void); -#ifdef CONFIG_X86_GOOD_APIC -# define FORCE_READ_AROUND_WRITE 0 -# define apic_read_around(x) -# define apic_write_around(x, y) apic_write((x), (y)) -#else -# define FORCE_READ_AROUND_WRITE 1 -# define apic_read_around(x) apic_read(x) -# define apic_write_around(x, y) apic_write_atomic((x), (y)) -#endif - static inline void ack_APIC_irq(void) { /* @@ -95,7 +85,7 @@ static inline void ack_APIC_irq(void) */ /* Docs say use 0 for future compatibility */ - apic_write_around(APIC_EOI, 0); + apic_write(APIC_EOI, 0); } extern int lapic_get_maxlvt(void); -- cgit v1.2.3-18-g5258 From baa1318841d4bc95d783e6c15219b264720002c8 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Mon, 14 Jul 2008 18:44:51 +0100 Subject: x86: APIC: Make apic_verbosity unsigned As a microoptimisation, make apic_verbosity unsigned. This will make apic_printk(APIC_QUIET, ...) expand into just printk(...) with the surrounding condition and a reference to apic_verbosity removed. Signed-off-by: Maciej W. Rozycki Signed-off-by: Ingo Molnar --- include/asm-x86/apic.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-x86/apic.h') diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h index ea866baccef..a3dd4c3e362 100644 --- a/include/asm-x86/apic.h +++ b/include/asm-x86/apic.h @@ -37,7 +37,7 @@ extern void generic_apic_probe(void); #ifdef CONFIG_X86_LOCAL_APIC -extern int apic_verbosity; +extern unsigned int apic_verbosity; extern int local_apic_timer_c2_ok; extern int ioapic_force; -- cgit v1.2.3-18-g5258 From 35b680557f95564f70f21a8d3f5c72e101fab260 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Fri, 18 Jul 2008 01:47:44 +0100 Subject: x86: more apic debugging [ mingo@elte.hu: picked up this patch from Maciej, lets make apic=debug print out more info - we had a lot of APIC changes ] Signed-off-by: Ingo Molnar --- include/asm-x86/apic.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-x86/apic.h') diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h index a3dd4c3e362..b96460a7190 100644 --- a/include/asm-x86/apic.h +++ b/include/asm-x86/apic.h @@ -12,7 +12,7 @@ #define ARCH_APICTIMER_STOPS_ON_C3 1 -#define Dprintk(x...) +#define Dprintk printk /* * Debugging macros -- cgit v1.2.3-18-g5258