MIPS: VDSO: Add implementations of gettimeofday() and clock_gettime()
Add user-mode implementations of gettimeofday() and clock_gettime() to the VDSO. This is currently usable with 2 clocksources: the CP0 count register, which is accessible to user-mode via RDHWR on R2 and later cores, or the MIPS Global Interrupt Controller (GIC) timer, which provides a "user-mode visible" section containing a mirror of its counter registers. This section must be mapped into user memory, which is done below the VDSO data page. When a supported clocksource is not in use, the VDSO functions will return -ENOSYS, which causes libc to fall back on the standard syscall path. When support for neither of these clocksources is compiled into the kernel at all, the VDSO still provides clock_gettime(), as the coarse realtime/monotonic clocks can still be implemented. However, gettimeofday() is not provided in this case as nothing can be done without a suitable clocksource. This causes the symbol lookup to fail in libc and it will then always use the standard syscall path. This patch includes a workaround for a bug in QEMU which results in RDHWR on the CP0 count register always returning a constant (incorrect) value. A fix for this has been submitted, and the workaround can be removed after the fix has been in stable releases for a reasonable amount of time. A simple performance test which calls gettimeofday() 1000 times in a loop and calculates the average execution time gives the following results on a Malta + I6400 (running at 20MHz): - Syscall: ~31000 ns - VDSO (GIC): ~15000 ns - VDSO (CP0): ~9500 ns [markos.chandras@imgtec.com: - Minor code re-arrangements in order for mappings to be made in the order they appear to the process' address space. - Move do_{monotonic, realtime} outside of the MIPS_CLOCK_VSYSCALL ifdef - Use gic_get_usm_range so we can do the GIC mapping in the arch/mips/kernel/vdso instead of the GIC irqchip driver] Signed-off-by: Alex Smith <alex.smith@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com> Cc: linux-kernel@vger.kernel.org Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/11338/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
parent
c0a9f72c15
commit
a7f4df4e21
9 changed files with 460 additions and 10 deletions
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@ -61,6 +61,8 @@ config MIPS
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select SYSCTL_EXCEPTION_TRACE
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select SYSCTL_EXCEPTION_TRACE
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select HAVE_VIRT_CPU_ACCOUNTING_GEN
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select HAVE_VIRT_CPU_ACCOUNTING_GEN
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select HAVE_IRQ_TIME_ACCOUNTING
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select HAVE_IRQ_TIME_ACCOUNTING
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select GENERIC_TIME_VSYSCALL
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select ARCH_CLOCKSOURCE_DATA
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menu "Machine selection"
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menu "Machine selection"
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@ -1040,6 +1042,9 @@ config CSRC_R4K
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config CSRC_SB1250
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config CSRC_SB1250
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bool
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bool
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config MIPS_CLOCK_VSYSCALL
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def_bool CSRC_R4K || CLKSRC_MIPS_GIC
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config GPIO_TXX9
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config GPIO_TXX9
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select ARCH_REQUIRE_GPIOLIB
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select ARCH_REQUIRE_GPIOLIB
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bool
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bool
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29
arch/mips/include/asm/clocksource.h
Normal file
29
arch/mips/include/asm/clocksource.h
Normal file
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@ -0,0 +1,29 @@
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/*
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* Copyright (C) 2015 Imagination Technologies
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* Author: Alex Smith <alex.smith@imgtec.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*/
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#ifndef __ASM_CLOCKSOURCE_H
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#define __ASM_CLOCKSOURCE_H
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#include <linux/types.h>
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/* VDSO clocksources. */
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#define VDSO_CLOCK_NONE 0 /* No suitable clocksource. */
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#define VDSO_CLOCK_R4K 1 /* Use the coprocessor 0 count. */
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#define VDSO_CLOCK_GIC 2 /* Use the GIC. */
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/**
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* struct arch_clocksource_data - Architecture-specific clocksource information.
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* @vdso_clock_mode: Method the VDSO should use to access the clocksource.
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*/
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struct arch_clocksource_data {
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u8 vdso_clock_mode;
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};
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#endif /* __ASM_CLOCKSOURCE_H */
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@ -13,6 +13,8 @@
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#include <linux/mm_types.h>
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#include <linux/mm_types.h>
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#include <asm/barrier.h>
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/**
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/**
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* struct mips_vdso_image - Details of a VDSO image.
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* struct mips_vdso_image - Details of a VDSO image.
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* @data: Pointer to VDSO image data (page-aligned).
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* @data: Pointer to VDSO image data (page-aligned).
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@ -53,18 +55,82 @@ extern struct mips_vdso_image vdso_image_n32;
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/**
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/**
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* union mips_vdso_data - Data provided by the kernel for the VDSO.
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* union mips_vdso_data - Data provided by the kernel for the VDSO.
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* @xtime_sec: Current real time (seconds part).
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* @xtime_nsec: Current real time (nanoseconds part, shifted).
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* @wall_to_mono_sec: Wall-to-monotonic offset (seconds part).
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* @wall_to_mono_nsec: Wall-to-monotonic offset (nanoseconds part).
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* @seq_count: Counter to synchronise updates (odd = updating).
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* @cs_shift: Clocksource shift value.
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* @clock_mode: Clocksource to use for time functions.
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* @cs_mult: Clocksource multiplier value.
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* @cs_cycle_last: Clock cycle value at last update.
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* @cs_mask: Clocksource mask value.
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* @tz_minuteswest: Minutes west of Greenwich (from timezone).
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* @tz_dsttime: Type of DST correction (from timezone).
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*
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*
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* This structure contains data needed by functions within the VDSO. It is
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* This structure contains data needed by functions within the VDSO. It is
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* populated by the kernel and mapped read-only into user memory.
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* populated by the kernel and mapped read-only into user memory. The time
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* fields are mirrors of internal data from the timekeeping infrastructure.
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*
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*
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* Note: Care should be taken when modifying as the layout must remain the same
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* Note: Care should be taken when modifying as the layout must remain the same
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* for both 64- and 32-bit (for 32-bit userland on 64-bit kernel).
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* for both 64- and 32-bit (for 32-bit userland on 64-bit kernel).
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*/
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*/
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union mips_vdso_data {
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union mips_vdso_data {
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struct {
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struct {
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u64 xtime_sec;
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u64 xtime_nsec;
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u32 wall_to_mono_sec;
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u32 wall_to_mono_nsec;
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u32 seq_count;
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u32 cs_shift;
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u8 clock_mode;
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u32 cs_mult;
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u64 cs_cycle_last;
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u64 cs_mask;
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s32 tz_minuteswest;
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s32 tz_dsttime;
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};
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};
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u8 page[PAGE_SIZE];
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u8 page[PAGE_SIZE];
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};
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};
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static inline u32 vdso_data_read_begin(const union mips_vdso_data *data)
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{
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u32 seq;
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while (true) {
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seq = ACCESS_ONCE(data->seq_count);
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if (likely(!(seq & 1))) {
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/* Paired with smp_wmb() in vdso_data_write_*(). */
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smp_rmb();
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return seq;
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}
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cpu_relax();
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}
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}
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static inline bool vdso_data_read_retry(const union mips_vdso_data *data,
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u32 start_seq)
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{
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/* Paired with smp_wmb() in vdso_data_write_*(). */
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smp_rmb();
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return unlikely(data->seq_count != start_seq);
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}
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static inline void vdso_data_write_begin(union mips_vdso_data *data)
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{
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++data->seq_count;
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/* Ensure sequence update is written before other data page values. */
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smp_wmb();
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}
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static inline void vdso_data_write_end(union mips_vdso_data *data)
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{
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/* Ensure data values are written before updating sequence again. */
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smp_wmb();
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++data->seq_count;
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}
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#endif /* __ASM_VDSO_H */
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#endif /* __ASM_VDSO_H */
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@ -28,6 +28,43 @@ static u64 notrace r4k_read_sched_clock(void)
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return read_c0_count();
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return read_c0_count();
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}
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}
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static inline unsigned int rdhwr_count(void)
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{
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unsigned int count;
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__asm__ __volatile__(
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" .set push\n"
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" .set mips32r2\n"
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" rdhwr %0, $2\n"
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" .set pop\n"
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: "=r" (count));
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return count;
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}
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static bool rdhwr_count_usable(void)
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{
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unsigned int prev, curr, i;
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/*
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* Older QEMUs have a broken implementation of RDHWR for the CP0 count
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* which always returns a constant value. Try to identify this and don't
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* use it in the VDSO if it is broken. This workaround can be removed
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* once the fix has been in QEMU stable for a reasonable amount of time.
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*/
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for (i = 0, prev = rdhwr_count(); i < 100; i++) {
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curr = rdhwr_count();
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if (curr != prev)
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return true;
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prev = curr;
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}
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pr_warn("Not using R4K clocksource in VDSO due to broken RDHWR\n");
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return false;
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}
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int __init init_r4k_clocksource(void)
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int __init init_r4k_clocksource(void)
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{
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{
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if (!cpu_has_counter || !mips_hpt_frequency)
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if (!cpu_has_counter || !mips_hpt_frequency)
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@ -36,6 +73,13 @@ int __init init_r4k_clocksource(void)
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/* Calculate a somewhat reasonable rating value */
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/* Calculate a somewhat reasonable rating value */
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clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
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clocksource_mips.rating = 200 + mips_hpt_frequency / 10000000;
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/*
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* R2 onwards makes the count accessible to user mode so it can be used
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* by the VDSO (HWREna is configured by configure_hwrena()).
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*/
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if (cpu_has_mips_r2_r6 && rdhwr_count_usable())
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clocksource_mips.archdata.vdso_clock_mode = VDSO_CLOCK_R4K;
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clocksource_register_hz(&clocksource_mips, mips_hpt_frequency);
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clocksource_register_hz(&clocksource_mips, mips_hpt_frequency);
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sched_clock_register(r4k_read_sched_clock, 32, mips_hpt_frequency);
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sched_clock_register(r4k_read_sched_clock, 32, mips_hpt_frequency);
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@ -12,9 +12,12 @@
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#include <linux/elf.h>
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#include <linux/elf.h>
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#include <linux/err.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/init.h>
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#include <linux/ioport.h>
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#include <linux/irqchip/mips-gic.h>
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#include <linux/mm.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/slab.h>
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#include <linux/timekeeper_internal.h>
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#include <asm/abi.h>
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#include <asm/abi.h>
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#include <asm/vdso.h>
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#include <asm/vdso.h>
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@ -23,7 +26,7 @@
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static union mips_vdso_data vdso_data __page_aligned_data;
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static union mips_vdso_data vdso_data __page_aligned_data;
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/*
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/*
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* Mapping for the VDSO data pages. The real pages are mapped manually, as
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* Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as
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* what we map and where within the area they are mapped is determined at
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* what we map and where within the area they are mapped is determined at
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* runtime.
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* runtime.
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*/
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*/
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@ -64,25 +67,67 @@ static int __init init_vdso(void)
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}
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}
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subsys_initcall(init_vdso);
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subsys_initcall(init_vdso);
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void update_vsyscall(struct timekeeper *tk)
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{
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vdso_data_write_begin(&vdso_data);
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vdso_data.xtime_sec = tk->xtime_sec;
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vdso_data.xtime_nsec = tk->tkr_mono.xtime_nsec;
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vdso_data.wall_to_mono_sec = tk->wall_to_monotonic.tv_sec;
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vdso_data.wall_to_mono_nsec = tk->wall_to_monotonic.tv_nsec;
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vdso_data.cs_shift = tk->tkr_mono.shift;
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vdso_data.clock_mode = tk->tkr_mono.clock->archdata.vdso_clock_mode;
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if (vdso_data.clock_mode != VDSO_CLOCK_NONE) {
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vdso_data.cs_mult = tk->tkr_mono.mult;
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vdso_data.cs_cycle_last = tk->tkr_mono.cycle_last;
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vdso_data.cs_mask = tk->tkr_mono.mask;
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}
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vdso_data_write_end(&vdso_data);
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}
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void update_vsyscall_tz(void)
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{
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if (vdso_data.clock_mode != VDSO_CLOCK_NONE) {
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vdso_data.tz_minuteswest = sys_tz.tz_minuteswest;
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vdso_data.tz_dsttime = sys_tz.tz_dsttime;
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}
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}
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int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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{
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{
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struct mips_vdso_image *image = current->thread.abi->vdso;
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struct mips_vdso_image *image = current->thread.abi->vdso;
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struct mm_struct *mm = current->mm;
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struct mm_struct *mm = current->mm;
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unsigned long base, vdso_addr;
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unsigned long gic_size, vvar_size, size, base, data_addr, vdso_addr;
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struct vm_area_struct *vma;
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struct vm_area_struct *vma;
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struct resource gic_res;
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int ret;
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int ret;
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down_write(&mm->mmap_sem);
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down_write(&mm->mmap_sem);
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base = get_unmapped_area(NULL, 0, PAGE_SIZE + image->size, 0, 0);
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/*
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* Determine total area size. This includes the VDSO data itself, the
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* data page, and the GIC user page if present. Always create a mapping
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* for the GIC user area if the GIC is present regardless of whether it
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* is the current clocksource, in case it comes into use later on. We
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* only map a page even though the total area is 64K, as we only need
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* the counter registers at the start.
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*/
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gic_size = gic_present ? PAGE_SIZE : 0;
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vvar_size = gic_size + PAGE_SIZE;
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size = vvar_size + image->size;
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base = get_unmapped_area(NULL, 0, size, 0, 0);
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if (IS_ERR_VALUE(base)) {
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if (IS_ERR_VALUE(base)) {
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ret = base;
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ret = base;
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goto out;
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goto out;
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}
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}
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vdso_addr = base + PAGE_SIZE;
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data_addr = base + gic_size;
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vdso_addr = data_addr + PAGE_SIZE;
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vma = _install_special_mapping(mm, base, PAGE_SIZE,
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vma = _install_special_mapping(mm, base, vvar_size,
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VM_READ | VM_MAYREAD,
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VM_READ | VM_MAYREAD,
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&vdso_vvar_mapping);
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&vdso_vvar_mapping);
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if (IS_ERR(vma)) {
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if (IS_ERR(vma)) {
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@ -90,8 +135,22 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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goto out;
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goto out;
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}
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}
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/* Map GIC user page. */
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if (gic_size) {
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ret = gic_get_usm_range(&gic_res);
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if (ret)
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goto out;
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ret = io_remap_pfn_range(vma, base,
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gic_res.start >> PAGE_SHIFT,
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gic_size,
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pgprot_noncached(PAGE_READONLY));
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if (ret)
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goto out;
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|
}
|
||||||
|
|
||||||
/* Map data page. */
|
/* Map data page. */
|
||||||
ret = remap_pfn_range(vma, base,
|
ret = remap_pfn_range(vma, data_addr,
|
||||||
virt_to_phys(&vdso_data) >> PAGE_SHIFT,
|
virt_to_phys(&vdso_data) >> PAGE_SHIFT,
|
||||||
PAGE_SIZE, PAGE_READONLY);
|
PAGE_SIZE, PAGE_READONLY);
|
||||||
if (ret)
|
if (ret)
|
||||||
|
|
232
arch/mips/vdso/gettimeofday.c
Normal file
232
arch/mips/vdso/gettimeofday.c
Normal file
|
@ -0,0 +1,232 @@
|
||||||
|
/*
|
||||||
|
* Copyright (C) 2015 Imagination Technologies
|
||||||
|
* Author: Alex Smith <alex.smith@imgtec.com>
|
||||||
|
*
|
||||||
|
* This program is free software; you can redistribute it and/or modify it
|
||||||
|
* under the terms of the GNU General Public License as published by the
|
||||||
|
* Free Software Foundation; either version 2 of the License, or (at your
|
||||||
|
* option) any later version.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include "vdso.h"
|
||||||
|
|
||||||
|
#include <linux/compiler.h>
|
||||||
|
#include <linux/irqchip/mips-gic.h>
|
||||||
|
#include <linux/time.h>
|
||||||
|
|
||||||
|
#include <asm/clocksource.h>
|
||||||
|
#include <asm/io.h>
|
||||||
|
#include <asm/mips-cm.h>
|
||||||
|
#include <asm/unistd.h>
|
||||||
|
#include <asm/vdso.h>
|
||||||
|
|
||||||
|
static __always_inline int do_realtime_coarse(struct timespec *ts,
|
||||||
|
const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
u32 start_seq;
|
||||||
|
|
||||||
|
do {
|
||||||
|
start_seq = vdso_data_read_begin(data);
|
||||||
|
|
||||||
|
ts->tv_sec = data->xtime_sec;
|
||||||
|
ts->tv_nsec = data->xtime_nsec >> data->cs_shift;
|
||||||
|
} while (vdso_data_read_retry(data, start_seq));
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static __always_inline int do_monotonic_coarse(struct timespec *ts,
|
||||||
|
const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
u32 start_seq;
|
||||||
|
u32 to_mono_sec;
|
||||||
|
u32 to_mono_nsec;
|
||||||
|
|
||||||
|
do {
|
||||||
|
start_seq = vdso_data_read_begin(data);
|
||||||
|
|
||||||
|
ts->tv_sec = data->xtime_sec;
|
||||||
|
ts->tv_nsec = data->xtime_nsec >> data->cs_shift;
|
||||||
|
|
||||||
|
to_mono_sec = data->wall_to_mono_sec;
|
||||||
|
to_mono_nsec = data->wall_to_mono_nsec;
|
||||||
|
} while (vdso_data_read_retry(data, start_seq));
|
||||||
|
|
||||||
|
ts->tv_sec += to_mono_sec;
|
||||||
|
timespec_add_ns(ts, to_mono_nsec);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
#ifdef CONFIG_CSRC_R4K
|
||||||
|
|
||||||
|
static __always_inline u64 read_r4k_count(void)
|
||||||
|
{
|
||||||
|
unsigned int count;
|
||||||
|
|
||||||
|
__asm__ __volatile__(
|
||||||
|
" .set push\n"
|
||||||
|
" .set mips32r2\n"
|
||||||
|
" rdhwr %0, $2\n"
|
||||||
|
" .set pop\n"
|
||||||
|
: "=r" (count));
|
||||||
|
|
||||||
|
return count;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#ifdef CONFIG_CLKSRC_MIPS_GIC
|
||||||
|
|
||||||
|
static __always_inline u64 read_gic_count(const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
void __iomem *gic = get_gic(data);
|
||||||
|
u32 hi, hi2, lo;
|
||||||
|
|
||||||
|
do {
|
||||||
|
hi = __raw_readl(gic + GIC_UMV_SH_COUNTER_63_32_OFS);
|
||||||
|
lo = __raw_readl(gic + GIC_UMV_SH_COUNTER_31_00_OFS);
|
||||||
|
hi2 = __raw_readl(gic + GIC_UMV_SH_COUNTER_63_32_OFS);
|
||||||
|
} while (hi2 != hi);
|
||||||
|
|
||||||
|
return (((u64)hi) << 32) + lo;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif
|
||||||
|
|
||||||
|
static __always_inline u64 get_ns(const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
u64 cycle_now, delta, nsec;
|
||||||
|
|
||||||
|
switch (data->clock_mode) {
|
||||||
|
#ifdef CONFIG_CSRC_R4K
|
||||||
|
case VDSO_CLOCK_R4K:
|
||||||
|
cycle_now = read_r4k_count();
|
||||||
|
break;
|
||||||
|
#endif
|
||||||
|
#ifdef CONFIG_CLKSRC_MIPS_GIC
|
||||||
|
case VDSO_CLOCK_GIC:
|
||||||
|
cycle_now = read_gic_count(data);
|
||||||
|
break;
|
||||||
|
#endif
|
||||||
|
default:
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
delta = (cycle_now - data->cs_cycle_last) & data->cs_mask;
|
||||||
|
|
||||||
|
nsec = (delta * data->cs_mult) + data->xtime_nsec;
|
||||||
|
nsec >>= data->cs_shift;
|
||||||
|
|
||||||
|
return nsec;
|
||||||
|
}
|
||||||
|
|
||||||
|
static __always_inline int do_realtime(struct timespec *ts,
|
||||||
|
const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
u32 start_seq;
|
||||||
|
u64 ns;
|
||||||
|
|
||||||
|
do {
|
||||||
|
start_seq = vdso_data_read_begin(data);
|
||||||
|
|
||||||
|
if (data->clock_mode == VDSO_CLOCK_NONE)
|
||||||
|
return -ENOSYS;
|
||||||
|
|
||||||
|
ts->tv_sec = data->xtime_sec;
|
||||||
|
ns = get_ns(data);
|
||||||
|
} while (vdso_data_read_retry(data, start_seq));
|
||||||
|
|
||||||
|
ts->tv_nsec = 0;
|
||||||
|
timespec_add_ns(ts, ns);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static __always_inline int do_monotonic(struct timespec *ts,
|
||||||
|
const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
u32 start_seq;
|
||||||
|
u64 ns;
|
||||||
|
u32 to_mono_sec;
|
||||||
|
u32 to_mono_nsec;
|
||||||
|
|
||||||
|
do {
|
||||||
|
start_seq = vdso_data_read_begin(data);
|
||||||
|
|
||||||
|
if (data->clock_mode == VDSO_CLOCK_NONE)
|
||||||
|
return -ENOSYS;
|
||||||
|
|
||||||
|
ts->tv_sec = data->xtime_sec;
|
||||||
|
ns = get_ns(data);
|
||||||
|
|
||||||
|
to_mono_sec = data->wall_to_mono_sec;
|
||||||
|
to_mono_nsec = data->wall_to_mono_nsec;
|
||||||
|
} while (vdso_data_read_retry(data, start_seq));
|
||||||
|
|
||||||
|
ts->tv_sec += to_mono_sec;
|
||||||
|
ts->tv_nsec = 0;
|
||||||
|
timespec_add_ns(ts, ns + to_mono_nsec);
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
#ifdef CONFIG_MIPS_CLOCK_VSYSCALL
|
||||||
|
|
||||||
|
/*
|
||||||
|
* This is behind the ifdef so that we don't provide the symbol when there's no
|
||||||
|
* possibility of there being a usable clocksource, because there's nothing we
|
||||||
|
* can do without it. When libc fails the symbol lookup it should fall back on
|
||||||
|
* the standard syscall path.
|
||||||
|
*/
|
||||||
|
int __vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
|
||||||
|
{
|
||||||
|
const union mips_vdso_data *data = get_vdso_data();
|
||||||
|
struct timespec ts;
|
||||||
|
int ret;
|
||||||
|
|
||||||
|
ret = do_realtime(&ts, data);
|
||||||
|
if (ret)
|
||||||
|
return ret;
|
||||||
|
|
||||||
|
if (tv) {
|
||||||
|
tv->tv_sec = ts.tv_sec;
|
||||||
|
tv->tv_usec = ts.tv_nsec / 1000;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (tz) {
|
||||||
|
tz->tz_minuteswest = data->tz_minuteswest;
|
||||||
|
tz->tz_dsttime = data->tz_dsttime;
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif /* CONFIG_CLKSRC_MIPS_GIC */
|
||||||
|
|
||||||
|
int __vdso_clock_gettime(clockid_t clkid, struct timespec *ts)
|
||||||
|
{
|
||||||
|
const union mips_vdso_data *data = get_vdso_data();
|
||||||
|
int ret;
|
||||||
|
|
||||||
|
switch (clkid) {
|
||||||
|
case CLOCK_REALTIME_COARSE:
|
||||||
|
ret = do_realtime_coarse(ts, data);
|
||||||
|
break;
|
||||||
|
case CLOCK_MONOTONIC_COARSE:
|
||||||
|
ret = do_monotonic_coarse(ts, data);
|
||||||
|
break;
|
||||||
|
case CLOCK_REALTIME:
|
||||||
|
ret = do_realtime(ts, data);
|
||||||
|
break;
|
||||||
|
case CLOCK_MONOTONIC:
|
||||||
|
ret = do_monotonic(ts, data);
|
||||||
|
break;
|
||||||
|
default:
|
||||||
|
ret = -ENOSYS;
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* If we return -ENOSYS libc should fall back to a syscall. */
|
||||||
|
return ret;
|
||||||
|
}
|
|
@ -77,4 +77,13 @@ static inline const union mips_vdso_data *get_vdso_data(void)
|
||||||
return (const union mips_vdso_data *)(get_vdso_base() - PAGE_SIZE);
|
return (const union mips_vdso_data *)(get_vdso_base() - PAGE_SIZE);
|
||||||
}
|
}
|
||||||
|
|
||||||
|
#ifdef CONFIG_CLKSRC_MIPS_GIC
|
||||||
|
|
||||||
|
static inline void __iomem *get_gic(const union mips_vdso_data *data)
|
||||||
|
{
|
||||||
|
return (void __iomem *)data - PAGE_SIZE;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif /* CONFIG_CLKSRC_MIPS_GIC */
|
||||||
|
|
||||||
#endif /* __ASSEMBLY__ */
|
#endif /* __ASSEMBLY__ */
|
||||||
|
|
|
@ -95,6 +95,11 @@ PHDRS
|
||||||
VERSION
|
VERSION
|
||||||
{
|
{
|
||||||
LINUX_2.6 {
|
LINUX_2.6 {
|
||||||
|
#ifndef DISABLE_MIPS_VDSO
|
||||||
|
global:
|
||||||
|
__vdso_clock_gettime;
|
||||||
|
__vdso_gettimeofday;
|
||||||
|
#endif
|
||||||
local: *;
|
local: *;
|
||||||
};
|
};
|
||||||
}
|
}
|
||||||
|
|
|
@ -140,9 +140,10 @@ static cycle_t gic_hpt_read(struct clocksource *cs)
|
||||||
}
|
}
|
||||||
|
|
||||||
static struct clocksource gic_clocksource = {
|
static struct clocksource gic_clocksource = {
|
||||||
.name = "GIC",
|
.name = "GIC",
|
||||||
.read = gic_hpt_read,
|
.read = gic_hpt_read,
|
||||||
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
|
||||||
|
.archdata = { .vdso_clock_mode = VDSO_CLOCK_GIC },
|
||||||
};
|
};
|
||||||
|
|
||||||
static void __init __gic_clocksource_init(void)
|
static void __init __gic_clocksource_init(void)
|
||||||
|
|
Loading…
Reference in a new issue