linux/arch/sparc/include/asm/timer_64.h
Peter Zijlstra 0cd39f4600 locking/seqlock, headers: Untangle the spaghetti monster
By using lockdep_assert_*() from seqlock.h, the spaghetti monster
attacked.

Attack back by reducing seqlock.h dependencies from two key high level headers:

 - <linux/seqlock.h>:               -Remove <linux/ww_mutex.h>
 - <linux/time.h>:                  -Remove <linux/seqlock.h>
 - <linux/sched.h>:                 +Add    <linux/seqlock.h>

The price was to add it to sched.h ...

Core header fallout, we add direct header dependencies instead of gaining them
parasitically from higher level headers:

 - <linux/dynamic_queue_limits.h>:  +Add <asm/bug.h>
 - <linux/hrtimer.h>:               +Add <linux/seqlock.h>
 - <linux/ktime.h>:                 +Add <asm/bug.h>
 - <linux/lockdep.h>:               +Add <linux/smp.h>
 - <linux/sched.h>:                 +Add <linux/seqlock.h>
 - <linux/videodev2.h>:             +Add <linux/kernel.h>

Arch headers fallout:

 - PARISC: <asm/timex.h>:           +Add <asm/special_insns.h>
 - SH:     <asm/io.h>:              +Add <asm/page.h>
 - SPARC:  <asm/timer_64.h>:        +Add <uapi/asm/asi.h>
 - SPARC:  <asm/vvar.h>:            +Add <asm/processor.h>, <asm/barrier.h>
                                    -Remove <linux/seqlock.h>
 - X86:    <asm/fixmap.h>:          +Add <asm/pgtable_types.h>
                                    -Remove <asm/acpi.h>

There's also a bunch of parasitic header dependency fallout in .c files, not listed
separately.

[ mingo: Extended the changelog, split up & fixed the original patch. ]

Co-developed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200804133438.GK2674@hirez.programming.kicks-ass.net
2020-08-06 16:13:13 +02:00

100 lines
2.4 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* timer.h: System timer definitions for sun5.
*
* Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
*/
#ifndef _SPARC64_TIMER_H
#define _SPARC64_TIMER_H
#include <uapi/asm/asi.h>
#include <linux/types.h>
#include <linux/init.h>
/* The most frequently accessed fields should be first,
* to fit into the same cacheline.
*/
struct sparc64_tick_ops {
unsigned long ticks_per_nsec_quotient;
unsigned long offset;
unsigned long long (*get_tick)(void);
int (*add_compare)(unsigned long);
unsigned long softint_mask;
void (*disable_irq)(void);
void (*init_tick)(void);
unsigned long (*add_tick)(unsigned long);
unsigned long (*get_frequency)(void);
unsigned long frequency;
char *name;
};
extern struct sparc64_tick_ops *tick_ops;
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 */