diff options
Diffstat (limited to 'drivers/net/ethernet/marvell/octeontx2/af/ptp.c')
| -rw-r--r-- | drivers/net/ethernet/marvell/octeontx2/af/ptp.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/ptp.c b/drivers/net/ethernet/marvell/octeontx2/af/ptp.c new file mode 100644 index 000000000000..c85ee22b3d2b --- /dev/null +++ b/drivers/net/ethernet/marvell/octeontx2/af/ptp.c @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Marvell PTP driver + * + * Copyright (C) 2018 Marvell International Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/pci.h> + +#include "ptp.h" + +#define DRV_NAME "Marvell PTP Driver" + +#define PCI_DEVID_OCTEONTX2_PTP 0xA00C +#define PCI_SUBSYS_DEVID_OCTX2_98xx_PTP 0xB100 +#define PCI_SUBSYS_DEVID_OCTX2_96XX_PTP 0xB200 +#define PCI_SUBSYS_DEVID_OCTX2_95XX_PTP 0xB300 +#define PCI_SUBSYS_DEVID_OCTX2_LOKI_PTP 0xB400 +#define PCI_DEVID_OCTEONTX2_RST 0xA085 + +#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 get_clock_rate(void) +{ + u64 ret = CLOCK_BASE_RATE * 16; + struct pci_dev *pdev; + void __iomem *base; + + pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM, + PCI_DEVID_OCTEONTX2_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 ptp *ptp_get(void) +{ + struct pci_dev *pdev; + struct ptp *ptp; + + pdev = pci_get_device(PCI_VENDOR_ID_CAVIUM, + PCI_DEVID_OCTEONTX2_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; +} + +void ptp_put(struct ptp *ptp) +{ + if (!ptp) + return; + + pci_dev_put(ptp->pdev); +} + +int ptp_adjfine(struct ptp *ptp, long scaled_ppm) +{ + bool neg_adj = false; + u64 comp; + u64 adj; + s64 ppb; + + 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) / ptp->clock_rate; + /* convert scaled_ppm to ppb */ + ppb = 1 + scaled_ppm; + ppb *= 125; + ppb >>= 13; + adj = comp * ppb; + adj = div_u64(adj, 1000000000ull); + comp = neg_adj ? comp - adj : comp + adj; + + writeq(comp, ptp->reg_base + PTP_CLOCK_COMP); + + return 0; +} + +static inline u64 get_tsc(bool is_pmu) +{ + return is_pmu ? read_sysreg(pmccntr_el0) : read_sysreg(cntvct_el0); +} + +int ptp_get_clock(struct ptp *ptp, bool is_pmu, u64 *clk, u64 *tsc) +{ + u64 end, start; + u8 retries = 0; + + do { + start = get_tsc(0); + *tsc = get_tsc(is_pmu); + *clk = readq(ptp->reg_base + PTP_CLOCK_HI); + end = get_tsc(0); + retries++; + } while (((end - start) > 50) && retries < 5); + + return 0; +} + +static int ptp_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct device *dev = &pdev->dev; + struct ptp *ptp; + u64 clock_comp; + u64 clock_cfg; + int err; + + ptp = devm_kzalloc(dev, sizeof(*ptp), GFP_KERNEL); + if (!ptp) { + err = -ENOMEM; + goto error; + } + + ptp->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; + + ptp->reg_base = pcim_iomap_table(pdev)[PCI_PTP_BAR_NO]; + + ptp->clock_rate = get_clock_rate(); + + clock_cfg = readq(ptp->reg_base + PTP_CLOCK_CFG); + clock_cfg |= PTP_CLOCK_CFG_PTP_EN; + writeq(clock_cfg, ptp->reg_base + PTP_CLOCK_CFG); + + clock_comp = ((u64)1000000000ull << 32) / ptp->clock_rate; + writeq(clock_comp, ptp->reg_base + PTP_CLOCK_COMP); + + pci_set_drvdata(pdev, ptp); + + return 0; + +error_free: + devm_kfree(dev, ptp); + +error: + /* For `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 ptp_remove(struct pci_dev *pdev) +{ + struct ptp *ptp = pci_get_drvdata(pdev); + u64 clock_cfg; + + if (IS_ERR_OR_NULL(ptp)) + return; + + clock_cfg = readq(ptp->reg_base + PTP_CLOCK_CFG); + clock_cfg &= ~PTP_CLOCK_CFG_PTP_EN; + writeq(clock_cfg, ptp->reg_base + PTP_CLOCK_CFG); +} + +static const struct pci_device_id ptp_id_table[] = { + { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, PCI_DEVID_OCTEONTX2_PTP, + PCI_VENDOR_ID_CAVIUM, + PCI_SUBSYS_DEVID_OCTX2_98xx_PTP) }, + { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, PCI_DEVID_OCTEONTX2_PTP, + PCI_VENDOR_ID_CAVIUM, + PCI_SUBSYS_DEVID_OCTX2_96XX_PTP) }, + { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, PCI_DEVID_OCTEONTX2_PTP, + PCI_VENDOR_ID_CAVIUM, + PCI_SUBSYS_DEVID_OCTX2_95XX_PTP) }, + { PCI_DEVICE_SUB(PCI_VENDOR_ID_CAVIUM, PCI_DEVID_OCTEONTX2_PTP, + PCI_VENDOR_ID_CAVIUM, + PCI_SUBSYS_DEVID_OCTX2_LOKI_PTP) }, + { 0, } +}; + +struct pci_driver ptp_driver = { + .name = DRV_NAME, + .id_table = ptp_id_table, + .probe = ptp_probe, + .remove = ptp_remove, +}; |