ptp: add FemtoClock3 Wireless as ptp hardware clock

The RENESAS FemtoClock3 Wireless is a high-performance jitter attenuator,
frequency translator, and clock synthesizer. The device is comprised of 3
digital PLLs (DPLL) to track CLKIN inputs and three independent low phase
noise fractional output dividers (FOD) that output low phase noise clocks.

FemtoClock3 supports one Time Synchronization (Time Sync) channel to enable
an external processor to control the phase and frequency of the Time Sync
channel and to take phase measurements using the TDC. Intended applications
are synchronization using the precision time protocol (PTP) and
synchronization with 0.5 Hz and 1 Hz signals from GNSS.
Signed-off-by: Min Li <min.li.xe@renesas.com>
Acked-by: Lee Jones <lee@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ptp/Kconfig

@@ -155,6 +155,18 @@ 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_FC3W
+	tristate "RENESAS FemtoClock3 Wireless as PTP clock"
+	depends on PTP_1588_CLOCK && I2C
+	default n
+	help
+	  This driver adds support for using Renesas FemtoClock3 Wireless
+	  as a PTP clock. This clock is only useful if your time stamping
+	  MAC is connected to the RENESAS chip.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called ptp_fc3.
+
 config PTP_1588_CLOCK_MOCK
 	tristate "Mock-up PTP clock"
 	depends on PTP_1588_CLOCK

drivers/ptp/Makefile

@@ -15,6 +15,7 @@ obj-$(CONFIG_PTP_1588_CLOCK_QORIQ)	+= ptp-qoriq.o
 ptp-qoriq-y				+= ptp_qoriq.o
 ptp-qoriq-$(CONFIG_DEBUG_FS)		+= ptp_qoriq_debugfs.o
 obj-$(CONFIG_PTP_1588_CLOCK_IDTCM)	+= ptp_clockmatrix.o
+obj-$(CONFIG_PTP_1588_CLOCK_FC3W)	+= ptp_fc3.o
 obj-$(CONFIG_PTP_1588_CLOCK_IDT82P33)	+= ptp_idt82p33.o
 obj-$(CONFIG_PTP_1588_CLOCK_MOCK)	+= ptp_mock.o
 obj-$(CONFIG_PTP_1588_CLOCK_VMW)	+= ptp_vmw.o

drivers/ptp/ptp_fc3.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * PTP hardware clock driver for the FemtoClock3 family of timing and
+ * synchronization devices.
+ *
+ * Copyright (C) 2023 Integrated Device Technology, Inc., a Renesas Company.
+ */
+#ifndef PTP_IDTFC3_H
+#define PTP_IDTFC3_H
+
+#include <linux/ktime.h>
+#include <linux/ptp_clock.h>
+#include <linux/regmap.h>
+
+#define FW_FILENAME	"idtfc3.bin"
+
+#define MAX_FFO_PPB	(244000)
+#define TDC_GET_PERIOD	(10)
+
+struct idtfc3 {
+	struct ptp_clock_info	caps;
+	struct ptp_clock	*ptp_clock;
+	struct device		*dev;
+	/* Mutex to protect operations from being interrupted */
+	struct mutex		*lock;
+	struct device		*mfd;
+	struct regmap		*regmap;
+	struct idtfc3_hw_param	hw_param;
+	u32			sub_sync_count;
+	u32			ns_per_sync;
+	int			tdc_offset_sign;
+	u64			tdc_apll_freq;
+	u32			time_ref_freq;
+	u16			fod_n;
+	u8			lpf_mode;
+	/* Time counter */
+	u32			last_counter;
+	s64			ns;
+	u32			ns_per_counter;
+	u32			tc_update_period;
+	u32			tc_write_timeout;
+	s64			tod_write_overhead;
+};
+
+#endif /* PTP_IDTFC3_H */

include/linux/mfd/idtRC38xxx_reg.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Register Map - Based on PolarBear_CSRs.RevA.xlsx (2023-04-21)
+ *
+ * Copyright (C) 2023 Integrated Device Technology, Inc., a Renesas Company.
+ */
+#ifndef MFD_IDTRC38XXX_REG
+#define MFD_IDTRC38XXX_REG
+
+/* GLOBAL */
+#define SOFT_RESET_CTRL		(0x15) /* Specific to FC3W */
+#define MISC_CTRL		(0x14) /* Specific to FC3A */
+#define APLL_REINIT		BIT(1)
+#define APLL_REINIT_VFC3A	BIT(2)
+
+#define DEVICE_ID		(0x2)
+#define DEVICE_ID_MASK		(0x1000) /* Bit 12 is 1 if FC3W and 0 if FC3A */
+#define DEVICE_ID_SHIFT		(12)
+
+/* FOD */
+#define FOD_0		(0x300)
+#define FOD_0_VFC3A	(0x400)
+#define FOD_1		(0x340)
+#define FOD_1_VFC3A	(0x440)
+#define FOD_2		(0x380)
+#define FOD_2_VFC3A	(0x480)
+
+/* TDCAPLL */
+#define TDC_CTRL		(0x44a) /* Specific to FC3W */
+#define TDC_ENABLE_CTRL		(0x169) /* Specific to FC3A */
+#define TDC_DAC_CAL_CTRL	(0x16a) /* Specific to FC3A */
+#define TDC_EN			BIT(0)
+#define TDC_DAC_RECAL_REQ	BIT(1)
+#define TDC_DAC_RECAL_REQ_VFC3A	BIT(0)
+
+#define TDC_FB_DIV_INT_CNFG		(0x442)
+#define TDC_FB_DIV_INT_CNFG_VFC3A	(0x162)
+#define TDC_FB_DIV_INT_MASK		GENMASK(7, 0)
+#define TDC_REF_DIV_CNFG		(0x443)
+#define TDC_REF_DIV_CNFG_VFC3A		(0x163)
+#define TDC_REF_DIV_CONFIG_MASK		GENMASK(2, 0)
+
+/* TIME SYNC CHANNEL */
+#define TIME_CLOCK_SRC		(0xa01) /* Specific to FC3W */
+#define TIME_CLOCK_COUNT	(0xa00) /* Specific to FC3W */
+#define TIME_CLOCK_COUNT_MASK	GENMASK(5, 0)
+
+#define SUB_SYNC_GEN_CNFG	(0xa04)
+
+#define TOD_COUNTER_READ_REQ		(0xa5f)
+#define TOD_COUNTER_READ_REQ_VFC3A	(0x6df)
+#define TOD_SYNC_LOAD_VAL_CTRL		(0xa10)
+#define TOD_SYNC_LOAD_VAL_CTRL_VFC3A	(0x690)
+#define SYNC_COUNTER_MASK		GENMASK_ULL(51, 0)
+#define SUB_SYNC_COUNTER_MASK		GENMASK(30, 0)
+#define TOD_SYNC_LOAD_REQ_CTRL		(0xa21)
+#define TOD_SYNC_LOAD_REQ_CTRL_VFC3A	(0x6a1)
+#define SYNC_LOAD_ENABLE		BIT(1)
+#define SUB_SYNC_LOAD_ENABLE		BIT(0)
+#define SYNC_LOAD_REQ			BIT(0)
+
+#define LPF_MODE_CNFG		(0xa80)
+#define LPF_MODE_CNFG_VFC3A	(0x700)
+enum lpf_mode {
+	LPF_DISABLED = 0,
+	LPF_WP       = 1,
+	LPF_HOLDOVER = 2,
+	LPF_WF       = 3,
+	LPF_INVALID  = 4
+};
+#define LPF_CTRL	(0xa98)
+#define LPF_CTRL_VFC3A	(0x718)
+#define LPF_EN		BIT(0)
+
+#define LPF_BW_CNFG	(0xa81)
+#define LPF_BW_SHIFT	GENMASK(7, 3)
+#define LPF_BW_MULT		GENMASK(2, 0)
+#define LPF_BW_SHIFT_DEFAULT	(0xb)
+#define LPF_BW_MULT_DEFAULT		(0x0)
+#define LPF_BW_SHIFT_1PPS		(0x5)
+
+#define LPF_WR_PHASE_CTRL	(0xaa8)
+#define LPF_WR_PHASE_CTRL_VFC3A	(0x728)
+#define LPF_WR_FREQ_CTRL	(0xab0)
+#define LPF_WR_FREQ_CTRL_VFC3A	(0x730)
+
+#define TIME_CLOCK_TDC_FANOUT_CNFG	(0xB00)
+#define TIME_SYNC_TO_TDC_EN	BIT(0)
+#define SIG1_MUX_SEL_MASK	GENMASK(7, 4)
+#define SIG2_MUX_SEL_MASK	GENMASK(11, 8)
+enum tdc_mux_sel {
+	REF0 = 0,
+	REF1 = 1,
+	REF2 = 2,
+	REF3 = 3,
+	REF_CLK5 = 4,
+	REF_CLK6 = 5,
+	DPLL_FB_TO_TDC = 6,
+	DPLL_FB_DIVIDED_TO_TDC = 7,
+	TIME_CLK_DIVIDED = 8,
+	TIME_SYNC = 9,
+};
+
+#define TIME_CLOCK_MEAS_CNFG	(0xB04)
+#define TDC_MEAS_MODE	BIT(0)
+enum tdc_meas_mode {
+	CONTINUOUS = 0,
+	ONE_SHOT = 1,
+	MEAS_MODE_INVALID = 2,
+};
+
+#define TIME_CLOCK_MEAS_DIV_CNFG	(0xB08)
+#define TIME_REF_DIV_MASK	GENMASK(29, 24)
+
+#define TIME_CLOCK_MEAS_CTRL	(0xB10)
+#define TDC_MEAS_EN	BIT(0)
+#define TDC_MEAS_START	BIT(1)
+
+#define TDC_FIFO_READ_REQ	(0xB2F)
+#define TDC_FIFO_READ		(0xB30)
+#define COARSE_MEAS_MASK	GENMASK_ULL(39, 13)
+#define FINE_MEAS_MASK		GENMASK(12, 0)
+
+#define TDC_FIFO_CTRL		(0xB12)
+#define FIFO_CLEAR		BIT(0)
+#define TDC_FIFO_STS		(0xB38)
+#define FIFO_FULL		BIT(1)
+#define FIFO_EMPTY		BIT(0)
+#define TDC_FIFO_EVENT		(0xB39)
+#define FIFO_OVERRUN		BIT(1)
+
+/* DPLL */
+#define MAX_REFERENCE_INDEX	(3)
+#define MAX_NUM_REF_PRIORITY	(4)
+
+#define MAX_DPLL_INDEX	(2)
+
+#define DPLL_STS		(0x580)
+#define DPLL_STS_VFC3A		(0x571)
+#define DPLL_STATE_STS_MASK	(0x70)
+#define DPLL_STATE_STS_SHIFT	(4)
+#define DPLL_REF_SEL_STS_MASK	(0x6)
+#define DPLL_REF_SEL_STS_SHIFT	(1)
+
+#define DPLL_REF_PRIORITY_CNFG			(0x502)
+#define DPLL_REFX_PRIORITY_DISABLE_MASK		(0xf)
+#define DPLL_REF0_PRIORITY_ENABLE_AND_SET_MASK	(0x31)
+#define DPLL_REF1_PRIORITY_ENABLE_AND_SET_MASK	(0xc2)
+#define DPLL_REF2_PRIORITY_ENABLE_AND_SET_MASK	(0x304)
+#define DPLL_REF3_PRIORITY_ENABLE_AND_SET_MASK	(0xc08)
+#define DPLL_REF0_PRIORITY_SHIFT		(4)
+#define DPLL_REF1_PRIORITY_SHIFT		(6)
+#define DPLL_REF2_PRIORITY_SHIFT		(8)
+#define DPLL_REF3_PRIORITY_SHIFT		(10)
+
+enum dpll_state {
+	DPLL_STATE_MIN             = 0,
+	DPLL_STATE_FREERUN         = DPLL_STATE_MIN,
+	DPLL_STATE_LOCKED          = 1,
+	DPLL_STATE_HOLDOVER        = 2,
+	DPLL_STATE_WRITE_FREQUENCY = 3,
+	DPLL_STATE_ACQUIRE         = 4,
+	DPLL_STATE_HITLESS_SWITCH  = 5,
+	DPLL_STATE_MAX             = DPLL_STATE_HITLESS_SWITCH
+};
+
+/* REFMON */
+#define LOSMON_STS_0		(0x81e)
+#define LOSMON_STS_0_VFC3A	(0x18e)
+#define LOSMON_STS_1		(0x82e)
+#define LOSMON_STS_1_VFC3A	(0x19e)
+#define LOSMON_STS_2		(0x83e)
+#define LOSMON_STS_2_VFC3A	(0x1ae)
+#define LOSMON_STS_3		(0x84e)
+#define LOSMON_STS_3_VFC3A	(0x1be)
+#define LOS_STS_MASK		(0x1)
+
+#define FREQMON_STS_0		(0x874)
+#define FREQMON_STS_0_VFC3A	(0x1d4)
+#define FREQMON_STS_1		(0x894)
+#define FREQMON_STS_1_VFC3A	(0x1f4)
+#define FREQMON_STS_2		(0x8b4)
+#define FREQMON_STS_2_VFC3A	(0x214)
+#define FREQMON_STS_3		(0x8d4)
+#define FREQMON_STS_3_VFC3A	(0x234)
+#define FREQ_FAIL_STS_SHIFT	(31)
+
+/* Firmware interface */
+#define TIME_CLK_FREQ_ADDR	(0xffa0)
+#define XTAL_FREQ_ADDR		(0xffa1)
+
+/*
+ * Return register address and field mask based on passed in firmware version
+ */
+#define IDTFC3_FW_REG(FW, VER, REG)	(((FW) < (VER)) ? (REG) : (REG##_##VER))
+#define IDTFC3_FW_FIELD(FW, VER, FIELD)	(((FW) < (VER)) ? (FIELD) : (FIELD##_##VER))
+enum fw_version {
+	V_DEFAULT = 0,
+	VFC3W     = 1,
+	VFC3A     = 2
+};
+
+/* XTAL_FREQ_ADDR/TIME_CLK_FREQ_ADDR */
+enum {
+	FREQ_MIN     = 0,
+	FREQ_25M     = 1,
+	FREQ_49_152M = 2,
+	FREQ_50M     = 3,
+	FREQ_100M    = 4,
+	FREQ_125M    = 5,
+	FREQ_250M    = 6,
+	FREQ_MAX
+};
+
+struct idtfc3_hw_param {
+	u32 xtal_freq;
+	u32 time_clk_freq;
+};
+
+struct idtfc3_fwrc {
+	u8 hiaddr;
+	u8 loaddr;
+	u8 value;
+	u8 reserved;
+} __packed;
+
+static inline void idtfc3_default_hw_param(struct idtfc3_hw_param *hw_param)
+{
+	hw_param->xtal_freq = 49152000;
+	hw_param->time_clk_freq = 25000000;
+}
+
+static inline int idtfc3_set_hw_param(struct idtfc3_hw_param *hw_param,
+				      u16 addr, u8 val)
+{
+	if (addr == XTAL_FREQ_ADDR)
+		switch (val) {
+		case FREQ_49_152M:
+			hw_param->xtal_freq = 49152000;
+			break;
+		case FREQ_50M:
+			hw_param->xtal_freq = 50000000;
+			break;
+		default:
+			return -EINVAL;
+		}
+	else if (addr == TIME_CLK_FREQ_ADDR)
+		switch (val) {
+		case FREQ_25M:
+			hw_param->time_clk_freq = 25000000;
+			break;
+		case FREQ_50M:
+			hw_param->time_clk_freq = 50000000;
+			break;
+		case FREQ_100M:
+			hw_param->time_clk_freq = 100000000;
+			break;
+		case FREQ_125M:
+			hw_param->time_clk_freq = 125000000;
+			break;
+		case FREQ_250M:
+			hw_param->time_clk_freq = 250000000;
+			break;
+		default:
+			return -EINVAL;
+		}
+	else
+		return -EFAULT;
+
+	return 0;
+}
+
+#endif