diff options
Diffstat (limited to 'drivers/ptp')
| -rw-r--r-- | drivers/ptp/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/ptp/Makefile | 1 | ||||
| -rw-r--r-- | drivers/ptp/ptp_vmw.c | 144 |
3 files changed, 157 insertions, 0 deletions
diff --git a/drivers/ptp/Kconfig b/drivers/ptp/Kconfig index 3b424ffceb83..86400c708150 100644 --- a/drivers/ptp/Kconfig +++ b/drivers/ptp/Kconfig @@ -139,4 +139,16 @@ config PTP_1588_CLOCK_IDTCM To compile this driver as a module, choose M here: the module will be called ptp_clockmatrix. +config PTP_1588_CLOCK_VMW + tristate "VMware virtual PTP clock" + depends on ACPI && HYPERVISOR_GUEST && X86 + depends on PTP_1588_CLOCK + help + This driver adds support for using VMware virtual precision + clock device as a PTP clock. This is only useful in virtual + machines running on VMware virtual infrastructure. + + To compile this driver as a module, choose M here: the module + will be called ptp_vmw. + endmenu diff --git a/drivers/ptp/Makefile b/drivers/ptp/Makefile index 01ff7fc3e820..7aff75f745dc 100644 --- a/drivers/ptp/Makefile +++ b/drivers/ptp/Makefile @@ -14,3 +14,4 @@ ptp-qoriq-y += ptp_qoriq.o ptp-qoriq-$(CONFIG_DEBUG_FS) += ptp_qoriq_debugfs.o obj-$(CONFIG_PTP_1588_CLOCK_IDTCM) += ptp_clockmatrix.o obj-$(CONFIG_PTP_1588_CLOCK_IDT82P33) += ptp_idt82p33.o +obj-$(CONFIG_PTP_1588_CLOCK_VMW) += ptp_vmw.o diff --git a/drivers/ptp/ptp_vmw.c b/drivers/ptp/ptp_vmw.c new file mode 100644 index 000000000000..5dca26e14bdc --- /dev/null +++ b/drivers/ptp/ptp_vmw.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause +/* + * Copyright (C) 2020 VMware, Inc., Palo Alto, CA., USA + * + * PTP clock driver for VMware precision clock virtual device. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/acpi.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/ptp_clock_kernel.h> +#include <asm/hypervisor.h> +#include <asm/vmware.h> + +#define VMWARE_MAGIC 0x564D5868 +#define VMWARE_CMD_PCLK(nr) ((nr << 16) | 97) +#define VMWARE_CMD_PCLK_GETTIME VMWARE_CMD_PCLK(0) + +static struct acpi_device *ptp_vmw_acpi_device; +static struct ptp_clock *ptp_vmw_clock; + + +static int ptp_vmw_pclk_read(u64 *ns) +{ + u32 ret, nsec_hi, nsec_lo, unused1, unused2, unused3; + + asm volatile (VMWARE_HYPERCALL : + "=a"(ret), "=b"(nsec_hi), "=c"(nsec_lo), "=d"(unused1), + "=S"(unused2), "=D"(unused3) : + "a"(VMWARE_MAGIC), "b"(0), + "c"(VMWARE_CMD_PCLK_GETTIME), "d"(0) : + "memory"); + + if (ret == 0) + *ns = ((u64)nsec_hi << 32) | nsec_lo; + return ret; +} + +/* + * PTP clock ops. + */ + +static int ptp_vmw_adjtime(struct ptp_clock_info *info, s64 delta) +{ + return -EOPNOTSUPP; +} + +static int ptp_vmw_adjfreq(struct ptp_clock_info *info, s32 delta) +{ + return -EOPNOTSUPP; +} + +static int ptp_vmw_gettime(struct ptp_clock_info *info, struct timespec64 *ts) +{ + u64 ns; + + if (ptp_vmw_pclk_read(&ns) != 0) + return -EIO; + *ts = ns_to_timespec64(ns); + return 0; +} + +static int ptp_vmw_settime(struct ptp_clock_info *info, + const struct timespec64 *ts) +{ + return -EOPNOTSUPP; +} + +static int ptp_vmw_enable(struct ptp_clock_info *info, + struct ptp_clock_request *request, int on) +{ + return -EOPNOTSUPP; +} + +static struct ptp_clock_info ptp_vmw_clock_info = { + .owner = THIS_MODULE, + .name = "ptp_vmw", + .max_adj = 0, + .adjtime = ptp_vmw_adjtime, + .adjfreq = ptp_vmw_adjfreq, + .gettime64 = ptp_vmw_gettime, + .settime64 = ptp_vmw_settime, + .enable = ptp_vmw_enable, +}; + +/* + * ACPI driver ops for VMware "precision clock" virtual device. + */ + +static int ptp_vmw_acpi_add(struct acpi_device *device) +{ + ptp_vmw_clock = ptp_clock_register(&ptp_vmw_clock_info, NULL); + if (IS_ERR(ptp_vmw_clock)) { + pr_err("failed to register ptp clock\n"); + return PTR_ERR(ptp_vmw_clock); + } + + ptp_vmw_acpi_device = device; + return 0; +} + +static int ptp_vmw_acpi_remove(struct acpi_device *device) +{ + ptp_clock_unregister(ptp_vmw_clock); + return 0; +} + +static const struct acpi_device_id ptp_vmw_acpi_device_ids[] = { + { "VMW0005", 0 }, + { "", 0 }, +}; + +MODULE_DEVICE_TABLE(acpi, ptp_vmw_acpi_device_ids); + +static struct acpi_driver ptp_vmw_acpi_driver = { + .name = "ptp_vmw", + .ids = ptp_vmw_acpi_device_ids, + .ops = { + .add = ptp_vmw_acpi_add, + .remove = ptp_vmw_acpi_remove + }, + .owner = THIS_MODULE +}; + +static int __init ptp_vmw_init(void) +{ + if (x86_hyper_type != X86_HYPER_VMWARE) + return -1; + return acpi_bus_register_driver(&ptp_vmw_acpi_driver); +} + +static void __exit ptp_vmw_exit(void) +{ + acpi_bus_unregister_driver(&ptp_vmw_acpi_driver); +} + +module_init(ptp_vmw_init); +module_exit(ptp_vmw_exit); + +MODULE_DESCRIPTION("VMware virtual PTP clock driver"); +MODULE_AUTHOR("VMware, Inc."); +MODULE_LICENSE("Dual BSD/GPL"); |