From 4929c83a6ce6584cb64381bf1407c487f67d588a Mon Sep 17 00:00:00 2001 From: Pavel Tatashin Date: Mon, 12 Jun 2017 16:41:47 -0400 Subject: [PATCH] sparc64: add hot-patched and inlined get_tick() Add the new get_tick() function that is hot-patched during boot based on processor we are booting on. Signed-off-by: Pavel Tatashin Reviewed-by: Steven Sistare Signed-off-by: David S. Miller --- arch/sparc/include/asm/timer_64.h | 60 +++++++++++++++++++++++++++++++ arch/sparc/kernel/time_64.c | 28 +++++++++++---- arch/sparc/kernel/vmlinux.lds.S | 5 +++ 3 files changed, 87 insertions(+), 6 deletions(-) diff --git a/arch/sparc/include/asm/timer_64.h b/arch/sparc/include/asm/timer_64.h index 61d07251792c..51bc3bc54bfe 100644 --- a/arch/sparc/include/asm/timer_64.h +++ b/arch/sparc/include/asm/timer_64.h @@ -34,4 +34,64 @@ unsigned long sparc64_get_clock_tick(unsigned int cpu); void setup_sparc64_timer(void); void __init time_init(void); +#define TICK_PRIV_BIT BIT(63) +#define TICKCMP_IRQ_BIT BIT(63) + +#define HBIRD_STICKCMP_ADDR 0x1fe0000f060UL +#define HBIRD_STICK_ADDR 0x1fe0000f070UL + +#define GET_TICK_NINSTR 13 +struct get_tick_patch { + unsigned int addr; + unsigned int tick[GET_TICK_NINSTR]; + unsigned int stick[GET_TICK_NINSTR]; +}; + +extern struct get_tick_patch __get_tick_patch; +extern struct get_tick_patch __get_tick_patch_end; + +static inline unsigned long get_tick(void) +{ + unsigned long tick, tmp1, tmp2; + + __asm__ __volatile__( + /* read hbtick 13 instructions */ + "661:\n" + " mov 0x1fe, %1\n" + " sllx %1, 0x20, %1\n" + " sethi %%hi(0xf000), %2\n" + " or %2, 0x70, %2\n" + " or %1, %2, %1\n" /* %1 = HBIRD_STICK_ADDR */ + " add %1, 8, %2\n" + " ldxa [%2]%3, %0\n" + " ldxa [%1]%3, %1\n" + " ldxa [%2]%3, %2\n" + " sub %2, %0, %0\n" /* don't modify %xcc */ + " brnz,pn %0, 661b\n" /* restart to save one register */ + " sllx %2, 32, %2\n" + " or %2, %1, %0\n" + /* Common/not patched code */ + " sllx %0, 1, %0\n" + " srlx %0, 1, %0\n" /* Clear TICK_PRIV_BIT */ + /* Beginning of patch section */ + " .section .get_tick_patch, \"ax\"\n" + " .word 661b\n" + /* read tick 2 instructions and 11 skipped */ + " ba 1f\n" + " rd %%tick, %0\n" + " .skip 4 * (%4 - 2)\n" + "1:\n" + /* read stick 2 instructions and 11 skipped */ + " ba 1f\n" + " rd %%asr24, %0\n" + " .skip 4 * (%4 - 2)\n" + "1:\n" + /* End of patch section */ + " .previous\n" + : "=&r" (tick), "=&r" (tmp1), "=&r" (tmp2) + : "i" (ASI_PHYS_BYPASS_EC_E), "i" (GET_TICK_NINSTR)); + + return tick; +} + #endif /* _SPARC64_TIMER_H */ diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c index d149276ddd80..ca27415c393a 100644 --- a/arch/sparc/kernel/time_64.c +++ b/arch/sparc/kernel/time_64.c @@ -47,15 +47,13 @@ #include #include #include +#include #include "entry.h" #include "kernel.h" DEFINE_SPINLOCK(rtc_lock); -#define TICK_PRIV_BIT (1UL << 63) -#define TICKCMP_IRQ_BIT (1UL << 63) - #ifdef CONFIG_SMP unsigned long profile_pc(struct pt_regs *regs) { @@ -290,9 +288,6 @@ static struct sparc64_tick_ops stick_operations __read_mostly = { * 2) write high * 3) write low */ -#define HBIRD_STICKCMP_ADDR 0x1fe0000f060UL -#define HBIRD_STICK_ADDR 0x1fe0000f070UL - static unsigned long __hbird_read_stick(void) { unsigned long ret, tmp1, tmp2, tmp3; @@ -777,6 +772,26 @@ static u64 clocksource_tick_read(struct clocksource *cs) return tick_operations.get_tick(); } +static void __init get_tick_patch(void) +{ + unsigned int *addr, *instr, i; + struct get_tick_patch *p; + + if (tlb_type == spitfire && is_hummingbird()) + return; + + for (p = &__get_tick_patch; p < &__get_tick_patch_end; p++) { + instr = (tlb_type == spitfire) ? p->tick : p->stick; + addr = (unsigned int *)(unsigned long)p->addr; + for (i = 0; i < GET_TICK_NINSTR; i++) { + addr[i] = instr[i]; + /* ensure that address is modified before flush */ + wmb(); + flushi(&addr[i]); + } + } +} + static void init_tick_ops(struct sparc64_tick_ops *ops) { unsigned long freq, quotient, tick; @@ -789,6 +804,7 @@ static void init_tick_ops(struct sparc64_tick_ops *ops) ops->ticks_per_nsec_quotient = quotient; ops->frequency = freq; tick_operations = *ops; + get_tick_patch(); } void __init time_init_early(void) diff --git a/arch/sparc/kernel/vmlinux.lds.S b/arch/sparc/kernel/vmlinux.lds.S index 572db686f845..03b3d65d1266 100644 --- a/arch/sparc/kernel/vmlinux.lds.S +++ b/arch/sparc/kernel/vmlinux.lds.S @@ -149,6 +149,11 @@ SECTIONS *(.sun_m7_2insn_patch) __sun_m7_2insn_patch_end = .; } + .get_tick_patch : { + __get_tick_patch = .; + *(.get_tick_patch) + __get_tick_patch_end = .; + } PERCPU_SECTION(SMP_CACHE_BYTES) #ifdef CONFIG_JUMP_LABEL -- 2.20.1