Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: 12a61f55864444d8eadc3c329496bccacb61e9c9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * OpenFirmware helpers for memory drivers
 *
 * Copyright (C) 2012 Texas Instruments, Inc.
 */

#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/of.h>
#include <linux/gfp.h>
#include <memory/jedec_ddr.h>
#include <linux/export.h>
#include "of_memory.h"

/**
 * of_get_min_tck() - extract min timing values for ddr
 * @np: pointer to ddr device tree node
 * @device: device requesting for min timing values
 *
 * Populates the lpddr2_min_tck structure by extracting data
 * from device tree node. Returns a pointer to the populated
 * structure. If any error in populating the structure, returns
 * default min timings provided by JEDEC.
 */
const struct lpddr2_min_tck *of_get_min_tck(struct device_node *np,
		struct device *dev)
{
	int			ret = 0;
	struct lpddr2_min_tck	*min;

	min = devm_kzalloc(dev, sizeof(*min), GFP_KERNEL);
	if (!min)
		goto default_min_tck;

	ret |= of_property_read_u32(np, "tRPab-min-tck", &min->tRPab);
	ret |= of_property_read_u32(np, "tRCD-min-tck", &min->tRCD);
	ret |= of_property_read_u32(np, "tWR-min-tck", &min->tWR);
	ret |= of_property_read_u32(np, "tRASmin-min-tck", &min->tRASmin);
	ret |= of_property_read_u32(np, "tRRD-min-tck", &min->tRRD);
	ret |= of_property_read_u32(np, "tWTR-min-tck", &min->tWTR);
	ret |= of_property_read_u32(np, "tXP-min-tck", &min->tXP);
	ret |= of_property_read_u32(np, "tRTP-min-tck", &min->tRTP);
	ret |= of_property_read_u32(np, "tCKE-min-tck", &min->tCKE);
	ret |= of_property_read_u32(np, "tCKESR-min-tck", &min->tCKESR);
	ret |= of_property_read_u32(np, "tFAW-min-tck", &min->tFAW);

	if (ret) {
		devm_kfree(dev, min);
		goto default_min_tck;
	}

	return min;

default_min_tck:
	dev_warn(dev, "%s: using default min-tck values\n", __func__);
	return &lpddr2_jedec_min_tck;
}
EXPORT_SYMBOL(of_get_min_tck);

static int of_do_get_timings(struct device_node *np,
		struct lpddr2_timings *tim)
{
	int ret;

	ret = of_property_read_u32(np, "max-freq", &tim->max_freq);
	ret |= of_property_read_u32(np, "min-freq", &tim->min_freq);
	ret |= of_property_read_u32(np, "tRPab", &tim->tRPab);
	ret |= of_property_read_u32(np, "tRCD", &tim->tRCD);
	ret |= of_property_read_u32(np, "tWR", &tim->tWR);
	ret |= of_property_read_u32(np, "tRAS-min", &tim->tRAS_min);
	ret |= of_property_read_u32(np, "tRRD", &tim->tRRD);
	ret |= of_property_read_u32(np, "tWTR", &tim->tWTR);
	ret |= of_property_read_u32(np, "tXP", &tim->tXP);
	ret |= of_property_read_u32(np, "tRTP", &tim->tRTP);
	ret |= of_property_read_u32(np, "tCKESR", &tim->tCKESR);
	ret |= of_property_read_u32(np, "tDQSCK-max", &tim->tDQSCK_max);
	ret |= of_property_read_u32(np, "tFAW", &tim->tFAW);
	ret |= of_property_read_u32(np, "tZQCS", &tim->tZQCS);
	ret |= of_property_read_u32(np, "tZQCL", &tim->tZQCL);
	ret |= of_property_read_u32(np, "tZQinit", &tim->tZQinit);
	ret |= of_property_read_u32(np, "tRAS-max-ns", &tim->tRAS_max_ns);
	ret |= of_property_read_u32(np, "tDQSCK-max-derated",
		&tim->tDQSCK_max_derated);

	return ret;
}

/**
 * of_get_ddr_timings() - extracts the ddr timings and updates no of
 * frequencies available.
 * @np_ddr: Pointer to ddr device tree node
 * @dev: Device requesting for ddr timings
 * @device_type: Type of ddr(LPDDR2 S2/S4)
 * @nr_frequencies: No of frequencies available for ddr
 * (updated by this function)
 *
 * Populates lpddr2_timings structure by extracting data from device
 * tree node. Returns pointer to populated structure. If any error
 * while populating, returns default timings provided by JEDEC.
 */
const struct lpddr2_timings *of_get_ddr_timings(struct device_node *np_ddr,
		struct device *dev, u32 device_type, u32 *nr_frequencies)
{
	struct lpddr2_timings	*timings = NULL;
	u32			arr_sz = 0, i = 0;
	struct device_node	*np_tim;
	char			*tim_compat = NULL;

	switch (device_type) {
	case DDR_TYPE_LPDDR2_S2:
	case DDR_TYPE_LPDDR2_S4:
		tim_compat = "jedec,lpddr2-timings";
		break;
	default:
		dev_warn(dev, "%s: un-supported memory type\n", __func__);
	}

	for_each_child_of_node(np_ddr, np_tim)
		if (of_device_is_compatible(np_tim, tim_compat))
			arr_sz++;

	if (arr_sz)
		timings = devm_kcalloc(dev, arr_sz, sizeof(*timings),
				       GFP_KERNEL);

	if (!timings)
		goto default_timings;

	for_each_child_of_node(np_ddr, np_tim) {
		if (of_device_is_compatible(np_tim, tim_compat)) {
			if (of_do_get_timings(np_tim, &timings[i])) {
				devm_kfree(dev, timings);
				goto default_timings;
			}
			i++;
		}
	}

	*nr_frequencies = arr_sz;

	return timings;

default_timings:
	dev_warn(dev, "%s: using default timings\n", __func__);
	*nr_frequencies = ARRAY_SIZE(lpddr2_jedec_timings);
	return lpddr2_jedec_timings;
}
EXPORT_SYMBOL(of_get_ddr_timings);