1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2018 Emlid Limited
4 */
5
6 #include <common.h>
7 #include <dm.h>
8 #include <log.h>
9 #include <dm/pinctrl.h>
10 #include <dm/read.h>
11 #include <regmap.h>
12 #include <syscon.h>
13 #include <asm/cpu.h>
14 #include <asm/scu.h>
15 #include <linux/io.h>
16
17 #define BUFCFG_OFFSET 0x100
18
19 #define MRFLD_FAMILY_LEN 0x400
20
21 /* These are taken from Linux kernel */
22 #define MRFLD_PINMODE_MASK 0x07
23
24 #define pin_to_bufno(f, p) ((p) - (f)->pin_base)
25
26 struct mrfld_family {
27 unsigned int family_number;
28 unsigned int pin_base;
29 size_t npins;
30 void __iomem *regs;
31 };
32
33 #define MRFLD_FAMILY(b, s, e) \
34 { \
35 .family_number = (b), \
36 .pin_base = (s), \
37 .npins = (e) - (s) + 1, \
38 }
39
40 /* Now we only support I2C family of pins */
41 static struct mrfld_family mrfld_families[] = {
42 MRFLD_FAMILY(7, 101, 114),
43 };
44
45 struct mrfld_pinctrl {
46 const struct mrfld_family *families;
47 size_t nfamilies;
48 };
49
50 static const struct mrfld_family *
mrfld_get_family(struct mrfld_pinctrl * mp,unsigned int pin)51 mrfld_get_family(struct mrfld_pinctrl *mp, unsigned int pin)
52 {
53 const struct mrfld_family *family;
54 unsigned int i;
55
56 for (i = 0; i < mp->nfamilies; i++) {
57 family = &mp->families[i];
58 if (pin >= family->pin_base &&
59 pin < family->pin_base + family->npins)
60 return family;
61 }
62
63 pr_err("failed to find family for pin %u\n", pin);
64 return NULL;
65 }
66
67 static void __iomem *
mrfld_get_bufcfg(struct mrfld_pinctrl * pinctrl,unsigned int pin)68 mrfld_get_bufcfg(struct mrfld_pinctrl *pinctrl, unsigned int pin)
69 {
70 const struct mrfld_family *family;
71 unsigned int bufno;
72
73 family = mrfld_get_family(pinctrl, pin);
74 if (!family)
75 return NULL;
76
77 bufno = pin_to_bufno(family, pin);
78
79 return family->regs + BUFCFG_OFFSET + bufno * 4;
80 }
81
82 static void
mrfld_setup_families(void * base_addr,struct mrfld_family * families,unsigned int nfam)83 mrfld_setup_families(void *base_addr,
84 struct mrfld_family *families, unsigned int nfam)
85 {
86 for (int i = 0; i < nfam; i++) {
87 struct mrfld_family *family = &families[i];
88
89 family->regs = base_addr +
90 family->family_number * MRFLD_FAMILY_LEN;
91 }
92 }
93
mrfld_pinconfig_protected(unsigned int pin,u32 mask,u32 bits)94 static int mrfld_pinconfig_protected(unsigned int pin, u32 mask, u32 bits)
95 {
96 struct mrfld_pinctrl *pinctrl;
97 struct udevice *dev;
98 void __iomem *bufcfg;
99 u32 v, value;
100 int ret;
101
102 ret = syscon_get_by_driver_data(X86_SYSCON_PINCONF, &dev);
103 if (ret)
104 return ret;
105
106 pinctrl = dev_get_priv(dev);
107
108 bufcfg = mrfld_get_bufcfg(pinctrl, pin);
109 if (!bufcfg)
110 return -EINVAL;
111
112 value = readl(bufcfg);
113
114 v = (value & ~mask) | (bits & mask);
115
116 debug("scu: v: 0x%x p: 0x%x bits: %d, mask: %d bufcfg: 0x%p\n",
117 v, (u32)bufcfg, bits, mask, bufcfg);
118
119 ret = scu_ipc_raw_command(IPCMSG_INDIRECT_WRITE, 0, &v, 4,
120 NULL, 0, (u32)bufcfg, 0);
121 if (ret)
122 pr_err("Failed to set mode via SCU for pin %u (%d)\n",
123 pin, ret);
124
125 return ret;
126 }
127
mrfld_pinctrl_cfg_pin(ofnode pin_node)128 static int mrfld_pinctrl_cfg_pin(ofnode pin_node)
129 {
130 bool is_protected;
131 int pad_offset;
132 int mode;
133 u32 mask;
134 int ret;
135
136 /* For now we only support just protected Family of pins */
137 is_protected = ofnode_read_bool(pin_node, "protected");
138 if (!is_protected)
139 return -ENOTSUPP;
140
141 pad_offset = ofnode_read_s32_default(pin_node, "pad-offset", -1);
142 if (pad_offset == -1)
143 return -EINVAL;
144
145 mode = ofnode_read_s32_default(pin_node, "mode-func", -1);
146 if (mode == -1)
147 return -EINVAL;
148
149 mask = MRFLD_PINMODE_MASK;
150
151 /* We don't support modes not in range 0..7 */
152 if (mode & ~mask)
153 return -ENOTSUPP;
154
155 ret = mrfld_pinconfig_protected(pad_offset, mask, mode);
156
157 return ret;
158 }
159
tangier_pinctrl_probe(struct udevice * dev)160 static int tangier_pinctrl_probe(struct udevice *dev)
161 {
162 void *base_addr = syscon_get_first_range(X86_SYSCON_PINCONF);
163 struct mrfld_pinctrl *pinctrl = dev_get_priv(dev);
164 ofnode pin_node;
165 int ret;
166
167 mrfld_setup_families(base_addr, mrfld_families,
168 ARRAY_SIZE(mrfld_families));
169
170 pinctrl->families = mrfld_families;
171 pinctrl->nfamilies = ARRAY_SIZE(mrfld_families);
172
173 ofnode_for_each_subnode(pin_node, dev_ofnode(dev)) {
174 ret = mrfld_pinctrl_cfg_pin(pin_node);
175 if (ret) {
176 pr_err("%s: invalid configuration for the pin %ld\n",
177 __func__, pin_node.of_offset);
178 }
179 }
180
181 return 0;
182 }
183
184 static const struct udevice_id tangier_pinctrl_match[] = {
185 { .compatible = "intel,pinctrl-tangier", .data = X86_SYSCON_PINCONF },
186 { /* sentinel */ }
187 };
188
189 U_BOOT_DRIVER(tangier_pinctrl) = {
190 .name = "tangier_pinctrl",
191 .id = UCLASS_SYSCON,
192 .of_match = tangier_pinctrl_match,
193 .probe = tangier_pinctrl_probe,
194 .priv_auto = sizeof(struct mrfld_pinctrl),
195 };
196