xref: /linux/drivers/net/ethernet/amd/xgbe/xgbe-pps.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1*5b5ba63aSRaju Rangoju // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-3-Clause)
2*5b5ba63aSRaju Rangoju /*
3*5b5ba63aSRaju Rangoju  * Copyright (c) 2014-2025, Advanced Micro Devices, Inc.
4*5b5ba63aSRaju Rangoju  * Copyright (c) 2014, Synopsys, Inc.
5*5b5ba63aSRaju Rangoju  * All rights reserved
6*5b5ba63aSRaju Rangoju  *
7*5b5ba63aSRaju Rangoju  * Author: Raju Rangoju <Raju.Rangoju@amd.com>
8*5b5ba63aSRaju Rangoju  */
9*5b5ba63aSRaju Rangoju 
10*5b5ba63aSRaju Rangoju #include "xgbe.h"
11*5b5ba63aSRaju Rangoju #include "xgbe-common.h"
12*5b5ba63aSRaju Rangoju 
13*5b5ba63aSRaju Rangoju static u32 get_pps_mask(unsigned int x)
14*5b5ba63aSRaju Rangoju {
15*5b5ba63aSRaju Rangoju 	return GENMASK(PPS_MAXIDX(x), PPS_MINIDX(x));
16*5b5ba63aSRaju Rangoju }
17*5b5ba63aSRaju Rangoju 
18*5b5ba63aSRaju Rangoju static u32 get_pps_cmd(unsigned int x, u32 val)
19*5b5ba63aSRaju Rangoju {
20*5b5ba63aSRaju Rangoju 	return (val & GENMASK(3, 0)) << PPS_MINIDX(x);
21*5b5ba63aSRaju Rangoju }
22*5b5ba63aSRaju Rangoju 
23*5b5ba63aSRaju Rangoju static u32 get_target_mode_sel(unsigned int x, u32 val)
24*5b5ba63aSRaju Rangoju {
25*5b5ba63aSRaju Rangoju 	return (val & GENMASK(1, 0)) << (PPS_MAXIDX(x) - 2);
26*5b5ba63aSRaju Rangoju }
27*5b5ba63aSRaju Rangoju 
28*5b5ba63aSRaju Rangoju int xgbe_pps_config(struct xgbe_prv_data *pdata,
29*5b5ba63aSRaju Rangoju 		    struct xgbe_pps_config *cfg, int index, bool on)
30*5b5ba63aSRaju Rangoju {
31*5b5ba63aSRaju Rangoju 	unsigned int ppscr = 0;
32*5b5ba63aSRaju Rangoju 	unsigned int tnsec;
33*5b5ba63aSRaju Rangoju 	u64 period;
34*5b5ba63aSRaju Rangoju 
35*5b5ba63aSRaju Rangoju 	/* Check if target time register is busy */
36*5b5ba63aSRaju Rangoju 	tnsec = XGMAC_IOREAD(pdata, MAC_PPSx_TTNSR(index));
37*5b5ba63aSRaju Rangoju 	if (XGMAC_GET_BITS(tnsec, MAC_PPSx_TTNSR, TRGTBUSY0))
38*5b5ba63aSRaju Rangoju 		return -EBUSY;
39*5b5ba63aSRaju Rangoju 
40*5b5ba63aSRaju Rangoju 	ppscr = XGMAC_IOREAD(pdata, MAC_PPSCR);
41*5b5ba63aSRaju Rangoju 	ppscr &= ~get_pps_mask(index);
42*5b5ba63aSRaju Rangoju 
43*5b5ba63aSRaju Rangoju 	if (!on) {
44*5b5ba63aSRaju Rangoju 		/* Disable PPS output */
45*5b5ba63aSRaju Rangoju 		ppscr |= get_pps_cmd(index, XGBE_PPSCMD_STOP);
46*5b5ba63aSRaju Rangoju 		ppscr |= PPSEN0;
47*5b5ba63aSRaju Rangoju 		XGMAC_IOWRITE(pdata, MAC_PPSCR, ppscr);
48*5b5ba63aSRaju Rangoju 
49*5b5ba63aSRaju Rangoju 		return 0;
50*5b5ba63aSRaju Rangoju 	}
51*5b5ba63aSRaju Rangoju 
52*5b5ba63aSRaju Rangoju 	/* Configure start time */
53*5b5ba63aSRaju Rangoju 	XGMAC_IOWRITE(pdata, MAC_PPSx_TTSR(index), cfg->start.tv_sec);
54*5b5ba63aSRaju Rangoju 	XGMAC_IOWRITE(pdata, MAC_PPSx_TTNSR(index), cfg->start.tv_nsec);
55*5b5ba63aSRaju Rangoju 
56*5b5ba63aSRaju Rangoju 	period = cfg->period.tv_sec * NSEC_PER_SEC + cfg->period.tv_nsec;
57*5b5ba63aSRaju Rangoju 	period = div_u64(period, XGBE_V2_TSTAMP_SSINC);
58*5b5ba63aSRaju Rangoju 
59*5b5ba63aSRaju Rangoju 	if (period < 4)
60*5b5ba63aSRaju Rangoju 		return -EINVAL;
61*5b5ba63aSRaju Rangoju 
62*5b5ba63aSRaju Rangoju 	/* Configure interval and pulse width (50% duty cycle) */
63*5b5ba63aSRaju Rangoju 	XGMAC_IOWRITE(pdata, MAC_PPSx_INTERVAL(index), period - 1);
64*5b5ba63aSRaju Rangoju 	XGMAC_IOWRITE(pdata, MAC_PPSx_WIDTH(index), (period >> 1) - 1);
65*5b5ba63aSRaju Rangoju 
66*5b5ba63aSRaju Rangoju 	/* Enable PPS with pulse train mode */
67*5b5ba63aSRaju Rangoju 	ppscr |= get_pps_cmd(index, XGBE_PPSCMD_START);
68*5b5ba63aSRaju Rangoju 	ppscr |= get_target_mode_sel(index, XGBE_PPSTARGET_PULSE);
69*5b5ba63aSRaju Rangoju 	ppscr |= PPSEN0;
70*5b5ba63aSRaju Rangoju 
71*5b5ba63aSRaju Rangoju 	XGMAC_IOWRITE(pdata, MAC_PPSCR, ppscr);
72*5b5ba63aSRaju Rangoju 
73*5b5ba63aSRaju Rangoju 	return 0;
74*5b5ba63aSRaju Rangoju }
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