[PATCH net-next v6 1/2] net: add support for Cavium PTP coprocessor
Aleksey Makarov
aleksey.makarov at cavium.com
Mon Jan 15 04:44:56 PST 2018
From: Radoslaw Biernacki <rad at semihalf.com>
This patch adds support for the Precision Time Protocol
Clocks and Timestamping hardware found on Cavium ThunderX
processors.
Signed-off-by: Radoslaw Biernacki <rad at semihalf.com>
Signed-off-by: Aleksey Makarov <aleksey.makarov at cavium.com>
Acked-by: Philippe Ombredanne <pombredanne at nexb.com>
---
drivers/net/ethernet/cavium/Kconfig | 12 +
drivers/net/ethernet/cavium/Makefile | 1 +
drivers/net/ethernet/cavium/common/Makefile | 1 +
drivers/net/ethernet/cavium/common/cavium_ptp.c | 353 ++++++++++++++++++++++++
drivers/net/ethernet/cavium/common/cavium_ptp.h | 70 +++++
5 files changed, 437 insertions(+)
create mode 100644 drivers/net/ethernet/cavium/common/Makefile
create mode 100644 drivers/net/ethernet/cavium/common/cavium_ptp.c
create mode 100644 drivers/net/ethernet/cavium/common/cavium_ptp.h
diff --git a/drivers/net/ethernet/cavium/Kconfig b/drivers/net/ethernet/cavium/Kconfig
index 63be75eb34d2..96586c0b4490 100644
--- a/drivers/net/ethernet/cavium/Kconfig
+++ b/drivers/net/ethernet/cavium/Kconfig
@@ -50,6 +50,18 @@ config THUNDER_NIC_RGX
This driver supports configuring XCV block of RGX interface
present on CN81XX chip.
+config CAVIUM_PTP
+ tristate "Cavium PTP coprocessor as PTP clock"
+ depends on 64BIT
+ imply PTP_1588_CLOCK
+ default y
+ ---help---
+ This driver adds support for the Precision Time Protocol Clocks and
+ Timestamping coprocessor (PTP) found on Cavium processors.
+ PTP provides timestamping mechanism that is suitable for use in IEEE 1588
+ Precision Time Protocol or other purposes. Timestamps can be used in
+ BGX, TNS, GTI, and NIC blocks.
+
config LIQUIDIO
tristate "Cavium LiquidIO support"
depends on 64BIT
diff --git a/drivers/net/ethernet/cavium/Makefile b/drivers/net/ethernet/cavium/Makefile
index 872da9f7c31a..946bba84e81d 100644
--- a/drivers/net/ethernet/cavium/Makefile
+++ b/drivers/net/ethernet/cavium/Makefile
@@ -1,6 +1,7 @@
#
# Makefile for the Cavium ethernet device drivers.
#
+obj-$(CONFIG_NET_VENDOR_CAVIUM) += common/
obj-$(CONFIG_NET_VENDOR_CAVIUM) += thunder/
obj-$(CONFIG_NET_VENDOR_CAVIUM) += liquidio/
obj-$(CONFIG_NET_VENDOR_CAVIUM) += octeon/
diff --git a/drivers/net/ethernet/cavium/common/Makefile b/drivers/net/ethernet/cavium/common/Makefile
new file mode 100644
index 000000000000..dd8561b8060b
--- /dev/null
+++ b/drivers/net/ethernet/cavium/common/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_CAVIUM_PTP) += cavium_ptp.o
diff --git a/drivers/net/ethernet/cavium/common/cavium_ptp.c b/drivers/net/ethernet/cavium/common/cavium_ptp.c
new file mode 100644
index 000000000000..c87c9c684a33
--- /dev/null
+++ b/drivers/net/ethernet/cavium/common/cavium_ptp.c
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0
+/* cavium_ptp.c - PTP 1588 clock on Cavium hardware
+ * Copyright (c) 2003-2015, 2017 Cavium, Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/timecounter.h>
+#include <linux/pci.h>
+
+#include "cavium_ptp.h"
+
+#define DRV_NAME "Cavium PTP Driver"
+
+#define PCI_DEVICE_ID_CAVIUM_PTP 0xA00C
+#define PCI_DEVICE_ID_CAVIUM_RST 0xA00E
+
+#define PCI_PTP_BAR_NO 0
+#define PCI_RST_BAR_NO 0
+
+#define PTP_CLOCK_CFG 0xF00ULL
+#define PTP_CLOCK_CFG_PTP_EN BIT(0)
+#define PTP_CLOCK_LO 0xF08ULL
+#define PTP_CLOCK_HI 0xF10ULL
+#define PTP_CLOCK_COMP 0xF18ULL
+
+#define RST_BOOT 0x1600ULL
+#define CLOCK_BASE_RATE 50000000ULL
+
+static u64 ptp_cavium_clock_get(void)
+{
+ struct pci_dev *pdev;
+ void __iomem *base;
+ u64 ret = CLOCK_BASE_RATE * 16;
+
+ pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM,
+ PCI_DEVICE_ID_CAVIUM_RST, NULL);
+ if (!pdev)
+ goto error;
+
+ base = pci_ioremap_bar(pdev, PCI_RST_BAR_NO);
+ if (!base)
+ goto error_put_pdev;
+
+ ret = CLOCK_BASE_RATE * ((readq(base + RST_BOOT) >> 33) & 0x3f);
+
+ iounmap(base);
+
+error_put_pdev:
+ pci_dev_put(pdev);
+
+error:
+ return ret;
+}
+
+struct cavium_ptp *cavium_ptp_get(void)
+{
+ struct cavium_ptp *ptp;
+ struct pci_dev *pdev;
+
+ pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM,
+ PCI_DEVICE_ID_CAVIUM_PTP, NULL);
+ if (!pdev)
+ return ERR_PTR(-ENODEV);
+
+ ptp = pci_get_drvdata(pdev);
+ if (!ptp)
+ ptp = ERR_PTR(-EPROBE_DEFER);
+ if (IS_ERR(ptp))
+ pci_dev_put(pdev);
+
+ return ptp;
+}
+EXPORT_SYMBOL(cavium_ptp_get);
+
+void cavium_ptp_put(struct cavium_ptp *ptp)
+{
+ pci_dev_put(ptp->pdev);
+}
+EXPORT_SYMBOL(cavium_ptp_put);
+
+/**
+ * cavium_ptp_adjfine() - Adjust ptp frequency
+ * @ptp: PTP clock info
+ * @scaled_ppm: how much to adjust by, in parts per million, but with a
+ * 16 bit binary fractional field
+ */
+static int cavium_ptp_adjfine(struct ptp_clock_info *ptp_info, long scaled_ppm)
+{
+ struct cavium_ptp *clock =
+ container_of(ptp_info, struct cavium_ptp, ptp_info);
+ unsigned long flags;
+ u64 comp;
+ u64 adj;
+ bool neg_adj = false;
+
+ if (scaled_ppm < 0) {
+ neg_adj = true;
+ scaled_ppm = -scaled_ppm;
+ }
+
+ /* The hardware adds the clock compensation value to the PTP clock
+ * on every coprocessor clock cycle. Typical convention is that it
+ * represent number of nanosecond betwen each cycle. In this
+ * convention compensation value is in 64 bit fixed-point
+ * representation where upper 32 bits are number of nanoseconds
+ * and lower is fractions of nanosecond.
+ * The scaled_ppm represent the ratio in "parts per bilion" by which the
+ * compensation value should be corrected.
+ * To calculate new compenstation value we use 64bit fixed point
+ * arithmetic on following formula
+ * comp = tbase + tbase * scaled_ppm / (1M * 2^16)
+ * where tbase is the basic compensation value calculated initialy
+ * in cavium_ptp_init() -> tbase = 1/Hz. Then we use endian
+ * independent structure definition to write data to PTP register.
+ */
+ comp = ((u64)1000000000ull << 32) / clock->clock_rate;
+ adj = comp * scaled_ppm;
+ adj >>= 16;
+ adj = div_u64(adj, 1000000ull);
+ comp = neg_adj ? comp - adj : comp + adj;
+
+ spin_lock_irqsave(&clock->spin_lock, flags);
+ writeq(comp, clock->reg_base + PTP_CLOCK_COMP);
+ spin_unlock_irqrestore(&clock->spin_lock, flags);
+
+ return 0;
+}
+
+/**
+ * cavium_ptp_adjtime() - Adjust ptp time
+ * @ptp: PTP clock info
+ * @delta: how much to adjust by, in nanosecs
+ */
+static int cavium_ptp_adjtime(struct ptp_clock_info *ptp_info, s64 delta)
+{
+ struct cavium_ptp *clock =
+ container_of(ptp_info, struct cavium_ptp, ptp_info);
+ unsigned long flags;
+
+ spin_lock_irqsave(&clock->spin_lock, flags);
+ timecounter_adjtime(&clock->time_counter, delta);
+ spin_unlock_irqrestore(&clock->spin_lock, flags);
+
+ /* Sync, for network driver to get latest value */
+ smp_mb();
+
+ return 0;
+}
+
+/**
+ * cavium_ptp_gettime() - Get hardware clock time with adjustment
+ * @ptp: PTP clock info
+ * @ts: timespec
+ */
+static int cavium_ptp_gettime(struct ptp_clock_info *ptp_info,
+ struct timespec64 *ts)
+{
+ struct cavium_ptp *clock =
+ container_of(ptp_info, struct cavium_ptp, ptp_info);
+ unsigned long flags;
+ u64 nsec;
+
+ spin_lock_irqsave(&clock->spin_lock, flags);
+ nsec = timecounter_read(&clock->time_counter);
+ spin_unlock_irqrestore(&clock->spin_lock, flags);
+
+ *ts = ns_to_timespec64(nsec);
+
+ return 0;
+}
+
+/**
+ * cavium_ptp_settime() - Set hardware clock time. Reset adjustment
+ * @ptp: PTP clock info
+ * @ts: timespec
+ */
+static int cavium_ptp_settime(struct ptp_clock_info *ptp_info,
+ const struct timespec64 *ts)
+{
+ struct cavium_ptp *clock =
+ container_of(ptp_info, struct cavium_ptp, ptp_info);
+ unsigned long flags;
+ u64 nsec;
+
+ nsec = timespec64_to_ns(ts);
+
+ spin_lock_irqsave(&clock->spin_lock, flags);
+ timecounter_init(&clock->time_counter, &clock->cycle_counter, nsec);
+ spin_unlock_irqrestore(&clock->spin_lock, flags);
+
+ return 0;
+}
+
+/**
+ * cavium_ptp_enable() - Request to enable or disable an ancillary feature.
+ * @ptp: PTP clock info
+ * @rq: request
+ * @on: is it on
+ */
+static int cavium_ptp_enable(struct ptp_clock_info *ptp_info,
+ struct ptp_clock_request *rq, int on)
+{
+ return -EOPNOTSUPP;
+}
+
+static u64 cavium_ptp_cc_read(const struct cyclecounter *cc)
+{
+ struct cavium_ptp *clock =
+ container_of(cc, struct cavium_ptp, cycle_counter);
+
+ return readq(clock->reg_base + PTP_CLOCK_HI);
+}
+
+static int cavium_ptp_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ struct device *dev = &pdev->dev;
+ struct cavium_ptp *clock;
+ struct cyclecounter *cc;
+ u64 clock_cfg;
+ u64 clock_comp;
+ int err;
+
+ clock = devm_kzalloc(dev, sizeof(*clock), GFP_KERNEL);
+ if (!clock) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ clock->pdev = pdev;
+
+ err = pcim_enable_device(pdev);
+ if (err)
+ goto error_free;
+
+ err = pcim_iomap_regions(pdev, 1 << PCI_PTP_BAR_NO, pci_name(pdev));
+ if (err)
+ goto error_free;
+
+ clock->reg_base = pcim_iomap_table(pdev)[PCI_PTP_BAR_NO];
+
+ spin_lock_init(&clock->spin_lock);
+
+ cc = &clock->cycle_counter;
+ cc->read = cavium_ptp_cc_read;
+ cc->mask = CYCLECOUNTER_MASK(64);
+ cc->mult = 1;
+ cc->shift = 0;
+
+ timecounter_init(&clock->time_counter, &clock->cycle_counter,
+ ktime_to_ns(ktime_get_real()));
+
+ clock->clock_rate = ptp_cavium_clock_get();
+
+ clock->ptp_info = (struct ptp_clock_info) {
+ .owner = THIS_MODULE,
+ .name = "ThunderX PTP",
+ .max_adj = 1000000000ull,
+ .n_ext_ts = 0,
+ .n_pins = 0,
+ .pps = 0,
+ .adjfine = cavium_ptp_adjfine,
+ .adjtime = cavium_ptp_adjtime,
+ .gettime64 = cavium_ptp_gettime,
+ .settime64 = cavium_ptp_settime,
+ .enable = cavium_ptp_enable,
+ };
+
+ clock_cfg = readq(clock->reg_base + PTP_CLOCK_CFG);
+ clock_cfg |= PTP_CLOCK_CFG_PTP_EN;
+ writeq(clock_cfg, clock->reg_base + PTP_CLOCK_CFG);
+
+ clock_comp = ((u64)1000000000ull << 32) / clock->clock_rate;
+ writeq(clock_comp, clock->reg_base + PTP_CLOCK_COMP);
+
+ clock->ptp_clock = ptp_clock_register(&clock->ptp_info, dev);
+ if (!clock->ptp_clock) {
+ err = -ENODEV;
+ goto error_stop;
+ }
+ if (IS_ERR(clock->ptp_clock)) {
+ err = PTR_ERR(clock->ptp_clock);
+ goto error_stop;
+ }
+
+ pci_set_drvdata(pdev, clock);
+ return 0;
+
+error_stop:
+ clock_cfg = readq(clock->reg_base + PTP_CLOCK_CFG);
+ clock_cfg &= ~PTP_CLOCK_CFG_PTP_EN;
+ writeq(clock_cfg, clock->reg_base + PTP_CLOCK_CFG);
+ pcim_iounmap_regions(pdev, 1 << PCI_PTP_BAR_NO);
+
+error_free:
+ devm_kfree(dev, clock);
+
+error:
+ /* For `cavium_ptp_get()` we need to differentiate between the case
+ * when the core has not tried to probe this device and the case when
+ * the probe failed. In the later case we pretend that the
+ * initialization was successful and keep the error in
+ * `dev->driver_data`.
+ */
+ pci_set_drvdata(pdev, ERR_PTR(err));
+ return 0;
+}
+
+static void cavium_ptp_remove(struct pci_dev *pdev)
+{
+ struct cavium_ptp *clock = pci_get_drvdata(pdev);
+ u64 clock_cfg;
+
+ if (IS_ERR_OR_NULL(clock))
+ return;
+
+ ptp_clock_unregister(clock->ptp_clock);
+
+ clock_cfg = readq(clock->reg_base + PTP_CLOCK_CFG);
+ clock_cfg &= ~PTP_CLOCK_CFG_PTP_EN;
+ writeq(clock_cfg, clock->reg_base + PTP_CLOCK_CFG);
+}
+
+static const struct pci_device_id cavium_ptp_id_table[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_CAVIUM_PTP) },
+ { 0, }
+};
+
+static struct pci_driver cavium_ptp_driver = {
+ .name = DRV_NAME,
+ .id_table = cavium_ptp_id_table,
+ .probe = cavium_ptp_probe,
+ .remove = cavium_ptp_remove,
+};
+
+static int __init cavium_ptp_init_module(void)
+{
+ return pci_register_driver(&cavium_ptp_driver);
+}
+
+static void __exit cavium_ptp_cleanup_module(void)
+{
+ pci_unregister_driver(&cavium_ptp_driver);
+}
+
+module_init(cavium_ptp_init_module);
+module_exit(cavium_ptp_cleanup_module);
+
+MODULE_DESCRIPTION(DRV_NAME);
+MODULE_AUTHOR("Cavium Networks <support at cavium.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(pci, cavium_ptp_id_table);
diff --git a/drivers/net/ethernet/cavium/common/cavium_ptp.h b/drivers/net/ethernet/cavium/common/cavium_ptp.h
new file mode 100644
index 000000000000..be2bafc7beeb
--- /dev/null
+++ b/drivers/net/ethernet/cavium/common/cavium_ptp.h
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0
+/* cavium_ptp.h - PTP 1588 clock on Cavium hardware
+ * Copyright (c) 2003-2015, 2017 Cavium, Inc.
+ */
+
+#ifndef CAVIUM_PTP_H
+#define CAVIUM_PTP_H
+
+#include <linux/ptp_clock_kernel.h>
+#include <linux/timecounter.h>
+
+struct cavium_ptp {
+ struct pci_dev *pdev;
+
+ /* Serialize access to cycle_counter, time_counter and hw_registers */
+ spinlock_t spin_lock;
+ struct cyclecounter cycle_counter;
+ struct timecounter time_counter;
+ void __iomem *reg_base;
+
+ u32 clock_rate;
+
+ struct ptp_clock_info ptp_info;
+ struct ptp_clock *ptp_clock;
+};
+
+#if IS_ENABLED(CONFIG_CAVIUM_PTP)
+
+struct cavium_ptp *cavium_ptp_get(void);
+void cavium_ptp_put(struct cavium_ptp *ptp);
+
+static inline u64 cavium_ptp_tstamp2time(struct cavium_ptp *ptp, u64 tstamp)
+{
+ unsigned long flags;
+ u64 ret;
+
+ spin_lock_irqsave(&ptp->spin_lock, flags);
+ ret = timecounter_cyc2time(&ptp->time_counter, tstamp);
+ spin_unlock_irqrestore(&ptp->spin_lock, flags);
+
+ return ret;
+}
+
+static inline int cavium_ptp_clock_index(struct cavium_ptp *clock)
+{
+ return ptp_clock_index(clock->ptp_clock);
+}
+
+#else
+
+static inline struct cavium_ptp *cavium_ptp_get(void)
+{
+ return ERR_PTR(-ENODEV);
+}
+
+static inline void cavium_ptp_put(struct cavium_ptp *ptp) {}
+
+static inline u64 cavium_ptp_tstamp2time(struct cavium_ptp *ptp, u64 tstamp)
+{
+ return 0;
+}
+
+static inline int cavium_ptp_clock_index(struct cavium_ptp *clock)
+{
+ return -1;
+}
+
+#endif
+
+#endif
--
2.15.1
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