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