diff options
Diffstat (limited to 'drivers/net/ethernet/renesas/rcar_gen4_ptp.c')
| -rw-r--r-- | drivers/net/ethernet/renesas/rcar_gen4_ptp.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/drivers/net/ethernet/renesas/rcar_gen4_ptp.c b/drivers/net/ethernet/renesas/rcar_gen4_ptp.c new file mode 100644 index 000000000000..d0979abd36de --- /dev/null +++ b/drivers/net/ethernet/renesas/rcar_gen4_ptp.c @@ -0,0 +1,187 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Renesas R-Car Gen4 gPTP device driver + * + * Copyright (C) 2022 Renesas Electronics Corporation + */ + +#include <linux/err.h> +#include <linux/etherdevice.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> + +#include "rcar_gen4_ptp.h" + +#define PTPTMEC_REG 0x0010 +#define PTPTMDC_REG 0x0014 +#define PTPTIVC0_REG 0x0020 +#define PTPTOVC00_REG 0x0030 +#define PTPTOVC10_REG 0x0034 +#define PTPTOVC20_REG 0x0038 +#define PTPGPTPTM00_REG 0x0050 +#define PTPGPTPTM10_REG 0x0054 +#define PTPGPTPTM20_REG 0x0058 + +#define ptp_to_priv(ptp) container_of(ptp, struct rcar_gen4_ptp_private, info) + +static int rcar_gen4_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + s64 addend = ptp_priv->default_addend; + bool neg_adj = scaled_ppm < 0; + s64 diff; + + if (neg_adj) + scaled_ppm = -scaled_ppm; + diff = div_s64(addend * scaled_ppm_to_ppb(scaled_ppm), NSEC_PER_SEC); + addend = neg_adj ? addend - diff : addend + diff; + + iowrite32(addend, ptp_priv->addr + PTPTIVC0_REG); + + return 0; +} + +static void _rcar_gen4_ptp_gettime(struct ptp_clock_info *ptp, + struct timespec64 *ts) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + + lockdep_assert_held(&ptp_priv->lock); + + ts->tv_nsec = ioread32(ptp_priv->addr + PTPGPTPTM00_REG); + ts->tv_sec = ioread32(ptp_priv->addr + PTPGPTPTM10_REG) | + ((s64)ioread32(ptp_priv->addr + PTPGPTPTM20_REG) << 32); +} + +static int rcar_gen4_ptp_gettime(struct ptp_clock_info *ptp, + struct timespec64 *ts) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + unsigned long flags; + + spin_lock_irqsave(&ptp_priv->lock, flags); + _rcar_gen4_ptp_gettime(ptp, ts); + spin_unlock_irqrestore(&ptp_priv->lock, flags); + + return 0; +} + +/* Caller must hold the lock */ +static void _rcar_gen4_ptp_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + + iowrite32(1, ptp_priv->addr + PTPTMDC_REG); + iowrite32(0, ptp_priv->addr + PTPTOVC20_REG); + iowrite32(0, ptp_priv->addr + PTPTOVC10_REG); + iowrite32(0, ptp_priv->addr + PTPTOVC00_REG); + iowrite32(1, ptp_priv->addr + PTPTMEC_REG); + iowrite32(ts->tv_sec >> 32, ptp_priv->addr + PTPTOVC20_REG); + iowrite32(ts->tv_sec, ptp_priv->addr + PTPTOVC10_REG); + iowrite32(ts->tv_nsec, ptp_priv->addr + PTPTOVC00_REG); +} + +static int rcar_gen4_ptp_settime(struct ptp_clock_info *ptp, + const struct timespec64 *ts) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + unsigned long flags; + + spin_lock_irqsave(&ptp_priv->lock, flags); + _rcar_gen4_ptp_settime(ptp, ts); + spin_unlock_irqrestore(&ptp_priv->lock, flags); + + return 0; +} + +static int rcar_gen4_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) +{ + struct rcar_gen4_ptp_private *ptp_priv = ptp_to_priv(ptp); + struct timespec64 ts; + unsigned long flags; + s64 now; + + spin_lock_irqsave(&ptp_priv->lock, flags); + _rcar_gen4_ptp_gettime(ptp, &ts); + now = ktime_to_ns(timespec64_to_ktime(ts)); + ts = ns_to_timespec64(now + delta); + _rcar_gen4_ptp_settime(ptp, &ts); + spin_unlock_irqrestore(&ptp_priv->lock, flags); + + return 0; +} + +static int rcar_gen4_ptp_enable(struct ptp_clock_info *ptp, + struct ptp_clock_request *rq, int on) +{ + return -EOPNOTSUPP; +} + +static struct ptp_clock_info rcar_gen4_ptp_info = { + .owner = THIS_MODULE, + .name = "rcar_gen4_ptp", + .max_adj = 50000000, + .adjfine = rcar_gen4_ptp_adjfine, + .adjtime = rcar_gen4_ptp_adjtime, + .gettime64 = rcar_gen4_ptp_gettime, + .settime64 = rcar_gen4_ptp_settime, + .enable = rcar_gen4_ptp_enable, +}; + +static s64 rcar_gen4_ptp_rate_to_increment(u32 rate) +{ + /* Timer increment in ns. + * bit[31:27] - integer + * bit[26:0] - decimal + * increment[ns] = perid[ns] * 2^27 => (1ns * 2^27) / rate[hz] + */ + return div_s64(1000000000LL << 27, rate); +} + +int rcar_gen4_ptp_register(struct rcar_gen4_ptp_private *ptp_priv, u32 rate) +{ + if (ptp_priv->initialized) + return 0; + + spin_lock_init(&ptp_priv->lock); + + ptp_priv->default_addend = rcar_gen4_ptp_rate_to_increment(rate); + iowrite32(ptp_priv->default_addend, ptp_priv->addr + PTPTIVC0_REG); + ptp_priv->clock = ptp_clock_register(&ptp_priv->info, NULL); + if (IS_ERR(ptp_priv->clock)) + return PTR_ERR(ptp_priv->clock); + + iowrite32(0x01, ptp_priv->addr + PTPTMEC_REG); + ptp_priv->initialized = true; + + return 0; +} +EXPORT_SYMBOL_GPL(rcar_gen4_ptp_register); + +int rcar_gen4_ptp_unregister(struct rcar_gen4_ptp_private *ptp_priv) +{ + iowrite32(1, ptp_priv->addr + PTPTMDC_REG); + + return ptp_clock_unregister(ptp_priv->clock); +} +EXPORT_SYMBOL_GPL(rcar_gen4_ptp_unregister); + +struct rcar_gen4_ptp_private *rcar_gen4_ptp_alloc(struct platform_device *pdev) +{ + struct rcar_gen4_ptp_private *ptp; + + ptp = devm_kzalloc(&pdev->dev, sizeof(*ptp), GFP_KERNEL); + if (!ptp) + return NULL; + + ptp->info = rcar_gen4_ptp_info; + + return ptp; +} +EXPORT_SYMBOL_GPL(rcar_gen4_ptp_alloc); + +MODULE_AUTHOR("Yoshihiro Shimoda"); +MODULE_DESCRIPTION("Renesas R-Car Gen4 gPTP driver"); +MODULE_LICENSE("GPL"); |