sparc64: add hot-patched and inlined get_tick() (4929c83a) · Commits · 戴 / test

arch/sparc/include/asm/timer_64.h

+60 −0

Original line number	Diff line number	Diff line
		@@ -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 */

arch/sparc/kernel/time_64.c

+22 −6

Original line number	Diff line number	Diff line
		@@ -47,15 +47,13 @@
		#include <asm/cpudata.h>
		#include <linux/uaccess.h>
		#include <asm/irq_regs.h>
		#include <asm/cacheflush.h>

		#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)

arch/sparc/kernel/vmlinux.lds.S

+5 −0

Original line number	Diff line number	Diff line
		@@ -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

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