1 // SPDX-License-Identifier: GPL-2.0-only 2 /******************************************************************************* 3 Copyright (C) 2013 Vayavya Labs Pvt Ltd 4 5 This implements all the API for managing HW timestamp & PTP. 6 7 8 Author: Rayagond Kokatanur <rayagond@vayavyalabs.com> 9 Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> 10 *******************************************************************************/ 11 12 #include <linux/io.h> 13 #include <linux/iopoll.h> 14 #include <linux/delay.h> 15 #include <linux/ptp_clock_kernel.h> 16 #include "common.h" 17 #include "stmmac_ptp.h" 18 #include "dwmac4.h" 19 #include "stmmac.h" 20 21 static void config_hw_tstamping(void __iomem *ioaddr, u32 data) 22 { 23 writel(data, ioaddr + PTP_TCR); 24 } 25 26 static void config_sub_second_increment(void __iomem *ioaddr, 27 u32 ptp_clock, int gmac4, u32 *ssinc) 28 { 29 u32 value = readl(ioaddr + PTP_TCR); 30 unsigned long data; 31 u32 reg_value; 32 33 /* For GMAC3.x, 4.x versions, in "fine adjustement mode" set sub-second 34 * increment to twice the number of nanoseconds of a clock cycle. 35 * The calculation of the default_addend value by the caller will set it 36 * to mid-range = 2^31 when the remainder of this division is zero, 37 * which will make the accumulator overflow once every 2 ptp_clock 38 * cycles, adding twice the number of nanoseconds of a clock cycle : 39 * 2000000000ULL / ptp_clock. 40 */ 41 if (value & PTP_TCR_TSCFUPDT) 42 data = (2000000000ULL / ptp_clock); 43 else 44 data = (1000000000ULL / ptp_clock); 45 46 /* 0.465ns accuracy */ 47 if (!(value & PTP_TCR_TSCTRLSSR)) 48 data = (data * 1000) / 465; 49 50 data &= PTP_SSIR_SSINC_MASK; 51 52 reg_value = data; 53 if (gmac4) 54 reg_value <<= GMAC4_PTP_SSIR_SSINC_SHIFT; 55 56 writel(reg_value, ioaddr + PTP_SSIR); 57 58 if (ssinc) 59 *ssinc = data; 60 } 61 62 static int init_systime(void __iomem *ioaddr, u32 sec, u32 nsec) 63 { 64 u32 value; 65 66 writel(sec, ioaddr + PTP_STSUR); 67 writel(nsec, ioaddr + PTP_STNSUR); 68 /* issue command to initialize the system time value */ 69 value = readl(ioaddr + PTP_TCR); 70 value |= PTP_TCR_TSINIT; 71 writel(value, ioaddr + PTP_TCR); 72 73 /* wait for present system time initialize to complete */ 74 return readl_poll_timeout(ioaddr + PTP_TCR, value, 75 !(value & PTP_TCR_TSINIT), 76 10000, 100000); 77 } 78 79 static int config_addend(void __iomem *ioaddr, u32 addend) 80 { 81 u32 value; 82 int limit; 83 84 writel(addend, ioaddr + PTP_TAR); 85 /* issue command to update the addend value */ 86 value = readl(ioaddr + PTP_TCR); 87 value |= PTP_TCR_TSADDREG; 88 writel(value, ioaddr + PTP_TCR); 89 90 /* wait for present addend update to complete */ 91 limit = 10; 92 while (limit--) { 93 if (!(readl(ioaddr + PTP_TCR) & PTP_TCR_TSADDREG)) 94 break; 95 mdelay(10); 96 } 97 if (limit < 0) 98 return -EBUSY; 99 100 return 0; 101 } 102 103 static int adjust_systime(void __iomem *ioaddr, u32 sec, u32 nsec, 104 int add_sub, int gmac4) 105 { 106 u32 value; 107 int limit; 108 109 if (add_sub) { 110 /* If the new sec value needs to be subtracted with 111 * the system time, then MAC_STSUR reg should be 112 * programmed with (2^32 – <new_sec_value>) 113 */ 114 if (gmac4) 115 sec = -sec; 116 117 value = readl(ioaddr + PTP_TCR); 118 if (value & PTP_TCR_TSCTRLSSR) 119 nsec = (PTP_DIGITAL_ROLLOVER_MODE - nsec); 120 else 121 nsec = (PTP_BINARY_ROLLOVER_MODE - nsec); 122 } 123 124 writel(sec, ioaddr + PTP_STSUR); 125 value = (add_sub << PTP_STNSUR_ADDSUB_SHIFT) | nsec; 126 writel(value, ioaddr + PTP_STNSUR); 127 128 /* issue command to initialize the system time value */ 129 value = readl(ioaddr + PTP_TCR); 130 value |= PTP_TCR_TSUPDT; 131 writel(value, ioaddr + PTP_TCR); 132 133 /* wait for present system time adjust/update to complete */ 134 limit = 10; 135 while (limit--) { 136 if (!(readl(ioaddr + PTP_TCR) & PTP_TCR_TSUPDT)) 137 break; 138 mdelay(10); 139 } 140 if (limit < 0) 141 return -EBUSY; 142 143 return 0; 144 } 145 146 static void get_systime(void __iomem *ioaddr, u64 *systime) 147 { 148 u64 ns, sec0, sec1; 149 150 /* Get the TSS value */ 151 sec1 = readl_relaxed(ioaddr + PTP_STSR); 152 do { 153 sec0 = sec1; 154 /* Get the TSSS value */ 155 ns = readl_relaxed(ioaddr + PTP_STNSR); 156 /* Get the TSS value */ 157 sec1 = readl_relaxed(ioaddr + PTP_STSR); 158 } while (sec0 != sec1); 159 160 if (systime) 161 *systime = ns + (sec1 * 1000000000ULL); 162 } 163 164 static void get_ptptime(void __iomem *ptpaddr, u64 *ptp_time) 165 { 166 u64 ns; 167 168 ns = readl(ptpaddr + PTP_ATNR); 169 ns += readl(ptpaddr + PTP_ATSR) * NSEC_PER_SEC; 170 171 *ptp_time = ns; 172 } 173 174 static void timestamp_interrupt(struct stmmac_priv *priv) 175 { 176 u32 num_snapshot, ts_status, tsync_int; 177 struct ptp_clock_event event; 178 unsigned long flags; 179 u64 ptp_time; 180 int i; 181 182 tsync_int = readl(priv->ioaddr + GMAC_INT_STATUS) & GMAC_INT_TSIE; 183 184 if (!tsync_int) 185 return; 186 187 /* Read timestamp status to clear interrupt from either external 188 * timestamp or start/end of PPS. 189 */ 190 ts_status = readl(priv->ioaddr + GMAC_TIMESTAMP_STATUS); 191 192 if (!priv->plat->ext_snapshot_en) 193 return; 194 195 num_snapshot = (ts_status & GMAC_TIMESTAMP_ATSNS_MASK) >> 196 GMAC_TIMESTAMP_ATSNS_SHIFT; 197 198 for (i = 0; i < num_snapshot; i++) { 199 read_lock_irqsave(&priv->ptp_lock, flags); 200 get_ptptime(priv->ptpaddr, &ptp_time); 201 read_unlock_irqrestore(&priv->ptp_lock, flags); 202 event.type = PTP_CLOCK_EXTTS; 203 event.index = 0; 204 event.timestamp = ptp_time; 205 ptp_clock_event(priv->ptp_clock, &event); 206 } 207 } 208 209 const struct stmmac_hwtimestamp stmmac_ptp = { 210 .config_hw_tstamping = config_hw_tstamping, 211 .init_systime = init_systime, 212 .config_sub_second_increment = config_sub_second_increment, 213 .config_addend = config_addend, 214 .adjust_systime = adjust_systime, 215 .get_systime = get_systime, 216 .get_ptptime = get_ptptime, 217 .timestamp_interrupt = timestamp_interrupt, 218 }; 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