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author | Jianyong Wu <jianyong.wu@arm.com> | 2020-12-09 14:09:26 +0800 |
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committer | Marc Zyngier <maz@kernel.org> | 2021-04-07 16:33:07 +0100 |
commit | a8cf291bdac5d415eadb55e79df1fca8c3f0dfef (patch) | |
tree | bedcf33fa4a90635e0d34c3becd2a701cfb4fb00 /drivers/ptp/ptp_kvm_common.c | |
parent | 923961a7ff2e94d3d824d9ea7047178a5a123245 (diff) | |
download | linux-a8cf291bdac5d415eadb55e79df1fca8c3f0dfef.tar.gz linux-a8cf291bdac5d415eadb55e79df1fca8c3f0dfef.tar.bz2 linux-a8cf291bdac5d415eadb55e79df1fca8c3f0dfef.zip |
ptp: Reorganize ptp_kvm.c to make it arch-independent
Currently, the ptp_kvm module contains a lot of x86-specific code.
Let's move this code into a new arch-specific file in the same directory,
and rename the arch-independent file to ptp_kvm_common.c.
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Jianyong Wu <jianyong.wu@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201209060932.212364-4-jianyong.wu@arm.com
Diffstat (limited to 'drivers/ptp/ptp_kvm_common.c')
-rw-r--r-- | drivers/ptp/ptp_kvm_common.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/ptp/ptp_kvm_common.c b/drivers/ptp/ptp_kvm_common.c new file mode 100644 index 000000000000..721ddcede5e1 --- /dev/null +++ b/drivers/ptp/ptp_kvm_common.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtual PTP 1588 clock for use with KVM guests + * + * Copyright (C) 2017 Red Hat Inc. + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/ptp_kvm.h> +#include <uapi/linux/kvm_para.h> +#include <asm/kvm_para.h> +#include <uapi/asm/kvm_para.h> + +#include <linux/ptp_clock_kernel.h> + +struct kvm_ptp_clock { + struct ptp_clock *ptp_clock; + struct ptp_clock_info caps; +}; + +static DEFINE_SPINLOCK(kvm_ptp_lock); + +static int ptp_kvm_get_time_fn(ktime_t *device_time, + struct system_counterval_t *system_counter, + void *ctx) +{ + long ret; + u64 cycle; + struct timespec64 tspec; + struct clocksource *cs; + + spin_lock(&kvm_ptp_lock); + + preempt_disable_notrace(); + ret = kvm_arch_ptp_get_crosststamp(&cycle, &tspec, &cs); + if (ret) { + spin_unlock(&kvm_ptp_lock); + preempt_enable_notrace(); + return ret; + } + + preempt_enable_notrace(); + + system_counter->cycles = cycle; + system_counter->cs = cs; + + *device_time = timespec64_to_ktime(tspec); + + spin_unlock(&kvm_ptp_lock); + + return 0; +} + +static int ptp_kvm_getcrosststamp(struct ptp_clock_info *ptp, + struct system_device_crosststamp *xtstamp) +{ + return get_device_system_crosststamp(ptp_kvm_get_time_fn, NULL, + NULL, xtstamp); +} + +/* + * PTP clock operations + */ + +static int ptp_kvm_adjfreq(struct ptp_clock_info *ptp, s32 ppb) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + return -EOPNOTSUPP; +} + +static int ptp_kvm_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) +{ + long ret; + struct timespec64 tspec; + + spin_lock(&kvm_ptp_lock); + + ret = kvm_arch_ptp_get_clock(&tspec); + if (ret) { + spin_unlock(&kvm_ptp_lock); + return ret; + } + + spin_unlock(&kvm_ptp_lock); + + memcpy(ts, &tspec, sizeof(struct timespec64)); + + return 0; +} + +static int ptp_kvm_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + return -EOPNOTSUPP; +} + +static const struct ptp_clock_info ptp_kvm_caps = { + .owner = THIS_MODULE, + .name = "KVM virtual PTP", + .max_adj = 0, + .n_ext_ts = 0, + .n_pins = 0, + .pps = 0, + .adjfreq = ptp_kvm_adjfreq, + .adjtime = ptp_kvm_adjtime, + .gettime64 = ptp_kvm_gettime, + .settime64 = ptp_kvm_settime, + .enable = ptp_kvm_enable, + .getcrosststamp = ptp_kvm_getcrosststamp, +}; + +/* module operations */ + +static struct kvm_ptp_clock kvm_ptp_clock; + +static void __exit ptp_kvm_exit(void) +{ + ptp_clock_unregister(kvm_ptp_clock.ptp_clock); +} + +static int __init ptp_kvm_init(void) +{ + long ret; + + ret = kvm_arch_ptp_init(); + if (ret) { + pr_err("fail to initialize ptp_kvm"); + return ret; + } + + kvm_ptp_clock.caps = ptp_kvm_caps; + + kvm_ptp_clock.ptp_clock = ptp_clock_register(&kvm_ptp_clock.caps, NULL); + + return PTR_ERR_OR_ZERO(kvm_ptp_clock.ptp_clock); +} + +module_init(ptp_kvm_init); +module_exit(ptp_kvm_exit); + +MODULE_AUTHOR("Marcelo Tosatti <mtosatti@redhat.com>"); +MODULE_DESCRIPTION("PTP clock using KVMCLOCK"); +MODULE_LICENSE("GPL"); |