1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/arch/arm/plat-pxa/mfp.c
4 *
5 * Multi-Function Pin Support
6 *
7 * Copyright (C) 2007 Marvell Internation Ltd.
8 *
9 * 2007-08-21: eric miao <eric.miao@marvell.com>
10 * initial version
11 */
12
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17
18 #include <linux/soc/pxa/mfp.h>
19
20 #define MFPR_SIZE (PAGE_SIZE)
21
22 /* MFPR register bit definitions */
23 #define MFPR_PULL_SEL (0x1 << 15)
24 #define MFPR_PULLUP_EN (0x1 << 14)
25 #define MFPR_PULLDOWN_EN (0x1 << 13)
26 #define MFPR_SLEEP_SEL (0x1 << 9)
27 #define MFPR_SLEEP_OE_N (0x1 << 7)
28 #define MFPR_EDGE_CLEAR (0x1 << 6)
29 #define MFPR_EDGE_FALL_EN (0x1 << 5)
30 #define MFPR_EDGE_RISE_EN (0x1 << 4)
31
32 #define MFPR_SLEEP_DATA(x) ((x) << 8)
33 #define MFPR_DRIVE(x) (((x) & 0x7) << 10)
34 #define MFPR_AF_SEL(x) (((x) & 0x7) << 0)
35
36 #define MFPR_EDGE_NONE (0)
37 #define MFPR_EDGE_RISE (MFPR_EDGE_RISE_EN)
38 #define MFPR_EDGE_FALL (MFPR_EDGE_FALL_EN)
39 #define MFPR_EDGE_BOTH (MFPR_EDGE_RISE | MFPR_EDGE_FALL)
40
41 /*
42 * Table that determines the low power modes outputs, with actual settings
43 * used in parentheses for don't-care values. Except for the float output,
44 * the configured driven and pulled levels match, so if there is a need for
45 * non-LPM pulled output, the same configuration could probably be used.
46 *
47 * Output value sleep_oe_n sleep_data pullup_en pulldown_en pull_sel
48 * (bit 7) (bit 8) (bit 14) (bit 13) (bit 15)
49 *
50 * Input 0 X(0) X(0) X(0) 0
51 * Drive 0 0 0 0 X(1) 0
52 * Drive 1 0 1 X(1) 0 0
53 * Pull hi (1) 1 X(1) 1 0 0
54 * Pull lo (0) 1 X(0) 0 1 0
55 * Z (float) 1 X(0) 0 0 0
56 */
57 #define MFPR_LPM_INPUT (0)
58 #define MFPR_LPM_DRIVE_LOW (MFPR_SLEEP_DATA(0) | MFPR_PULLDOWN_EN)
59 #define MFPR_LPM_DRIVE_HIGH (MFPR_SLEEP_DATA(1) | MFPR_PULLUP_EN)
60 #define MFPR_LPM_PULL_LOW (MFPR_LPM_DRIVE_LOW | MFPR_SLEEP_OE_N)
61 #define MFPR_LPM_PULL_HIGH (MFPR_LPM_DRIVE_HIGH | MFPR_SLEEP_OE_N)
62 #define MFPR_LPM_FLOAT (MFPR_SLEEP_OE_N)
63 #define MFPR_LPM_MASK (0xe080)
64
65 /*
66 * The pullup and pulldown state of the MFP pin at run mode is by default
67 * determined by the selected alternate function. In case that some buggy
68 * devices need to override this default behavior, the definitions below
69 * indicates the setting of corresponding MFPR bits
70 *
71 * Definition pull_sel pullup_en pulldown_en
72 * MFPR_PULL_NONE 0 0 0
73 * MFPR_PULL_LOW 1 0 1
74 * MFPR_PULL_HIGH 1 1 0
75 * MFPR_PULL_BOTH 1 1 1
76 * MFPR_PULL_FLOAT 1 0 0
77 */
78 #define MFPR_PULL_NONE (0)
79 #define MFPR_PULL_LOW (MFPR_PULL_SEL | MFPR_PULLDOWN_EN)
80 #define MFPR_PULL_BOTH (MFPR_PULL_LOW | MFPR_PULLUP_EN)
81 #define MFPR_PULL_HIGH (MFPR_PULL_SEL | MFPR_PULLUP_EN)
82 #define MFPR_PULL_FLOAT (MFPR_PULL_SEL)
83
84 /* mfp_spin_lock is used to ensure that MFP register configuration
85 * (most likely a read-modify-write operation) is atomic, and that
86 * mfp_table[] is consistent
87 */
88 static DEFINE_SPINLOCK(mfp_spin_lock);
89
90 static void __iomem *mfpr_mmio_base;
91
92 struct mfp_pin {
93 unsigned long config; /* -1 for not configured */
94 unsigned long mfpr_off; /* MFPRxx Register offset */
95 unsigned long mfpr_run; /* Run-Mode Register Value */
96 unsigned long mfpr_lpm; /* Low Power Mode Register Value */
97 };
98
99 static struct mfp_pin mfp_table[MFP_PIN_MAX];
100
101 /* mapping of MFP_LPM_* definitions to MFPR_LPM_* register bits */
102 static const unsigned long mfpr_lpm[] = {
103 MFPR_LPM_INPUT,
104 MFPR_LPM_DRIVE_LOW,
105 MFPR_LPM_DRIVE_HIGH,
106 MFPR_LPM_PULL_LOW,
107 MFPR_LPM_PULL_HIGH,
108 MFPR_LPM_FLOAT,
109 MFPR_LPM_INPUT,
110 };
111
112 /* mapping of MFP_PULL_* definitions to MFPR_PULL_* register bits */
113 static const unsigned long mfpr_pull[] = {
114 MFPR_PULL_NONE,
115 MFPR_PULL_LOW,
116 MFPR_PULL_HIGH,
117 MFPR_PULL_BOTH,
118 MFPR_PULL_FLOAT,
119 };
120
121 /* mapping of MFP_LPM_EDGE_* definitions to MFPR_EDGE_* register bits */
122 static const unsigned long mfpr_edge[] = {
123 MFPR_EDGE_NONE,
124 MFPR_EDGE_RISE,
125 MFPR_EDGE_FALL,
126 MFPR_EDGE_BOTH,
127 };
128
129 #define mfpr_readl(off) \
130 __raw_readl(mfpr_mmio_base + (off))
131
132 #define mfpr_writel(off, val) \
133 __raw_writel(val, mfpr_mmio_base + (off))
134
135 #define mfp_configured(p) ((p)->config != -1)
136
137 /*
138 * perform a read-back of any valid MFPR register to make sure the
139 * previous writings are finished
140 */
141 static unsigned long mfpr_off_readback;
142 #define mfpr_sync() (void)__raw_readl(mfpr_mmio_base + mfpr_off_readback)
143
__mfp_config_run(struct mfp_pin * p)144 static inline void __mfp_config_run(struct mfp_pin *p)
145 {
146 if (mfp_configured(p))
147 mfpr_writel(p->mfpr_off, p->mfpr_run);
148 }
149
__mfp_config_lpm(struct mfp_pin * p)150 static inline void __mfp_config_lpm(struct mfp_pin *p)
151 {
152 if (mfp_configured(p)) {
153 unsigned long mfpr_clr = (p->mfpr_run & ~MFPR_EDGE_BOTH) | MFPR_EDGE_CLEAR;
154 if (mfpr_clr != p->mfpr_run)
155 mfpr_writel(p->mfpr_off, mfpr_clr);
156 if (p->mfpr_lpm != mfpr_clr)
157 mfpr_writel(p->mfpr_off, p->mfpr_lpm);
158 }
159 }
160
mfp_config(unsigned long * mfp_cfgs,int num)161 void mfp_config(unsigned long *mfp_cfgs, int num)
162 {
163 unsigned long flags;
164 int i;
165
166 spin_lock_irqsave(&mfp_spin_lock, flags);
167
168 for (i = 0; i < num; i++, mfp_cfgs++) {
169 unsigned long tmp, c = *mfp_cfgs;
170 struct mfp_pin *p;
171 int pin, af, drv, lpm, edge, pull;
172
173 pin = MFP_PIN(c);
174 BUG_ON(pin >= MFP_PIN_MAX);
175 p = &mfp_table[pin];
176
177 af = MFP_AF(c);
178 drv = MFP_DS(c);
179 lpm = MFP_LPM_STATE(c);
180 edge = MFP_LPM_EDGE(c);
181 pull = MFP_PULL(c);
182
183 /* run-mode pull settings will conflict with MFPR bits of
184 * low power mode state, calculate mfpr_run and mfpr_lpm
185 * individually if pull != MFP_PULL_NONE
186 */
187 tmp = MFPR_AF_SEL(af) | MFPR_DRIVE(drv);
188
189 if (likely(pull == MFP_PULL_NONE)) {
190 p->mfpr_run = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
191 p->mfpr_lpm = p->mfpr_run;
192 } else {
193 p->mfpr_lpm = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
194 p->mfpr_run = tmp | mfpr_pull[pull];
195 }
196
197 p->config = c; __mfp_config_run(p);
198 }
199
200 mfpr_sync();
201 spin_unlock_irqrestore(&mfp_spin_lock, flags);
202 }
203
mfp_read(int mfp)204 unsigned long mfp_read(int mfp)
205 {
206 unsigned long val, flags;
207
208 BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
209
210 spin_lock_irqsave(&mfp_spin_lock, flags);
211 val = mfpr_readl(mfp_table[mfp].mfpr_off);
212 spin_unlock_irqrestore(&mfp_spin_lock, flags);
213
214 return val;
215 }
216
mfp_write(int mfp,unsigned long val)217 void mfp_write(int mfp, unsigned long val)
218 {
219 unsigned long flags;
220
221 BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
222
223 spin_lock_irqsave(&mfp_spin_lock, flags);
224 mfpr_writel(mfp_table[mfp].mfpr_off, val);
225 mfpr_sync();
226 spin_unlock_irqrestore(&mfp_spin_lock, flags);
227 }
228
mfp_init_base(void __iomem * mfpr_base)229 void __init mfp_init_base(void __iomem *mfpr_base)
230 {
231 int i;
232
233 /* initialize the table with default - unconfigured */
234 for (i = 0; i < ARRAY_SIZE(mfp_table); i++)
235 mfp_table[i].config = -1;
236
237 mfpr_mmio_base = mfpr_base;
238 }
239
mfp_init_addr(struct mfp_addr_map * map)240 void __init mfp_init_addr(struct mfp_addr_map *map)
241 {
242 struct mfp_addr_map *p;
243 unsigned long offset, flags;
244 int i;
245
246 spin_lock_irqsave(&mfp_spin_lock, flags);
247
248 /* mfp offset for readback */
249 mfpr_off_readback = map[0].offset;
250
251 for (p = map; p->start != MFP_PIN_INVALID; p++) {
252 offset = p->offset;
253 i = p->start;
254
255 do {
256 mfp_table[i].mfpr_off = offset;
257 mfp_table[i].mfpr_run = 0;
258 mfp_table[i].mfpr_lpm = 0;
259 offset += 4; i++;
260 } while ((i <= p->end) && (p->end != -1));
261 }
262
263 spin_unlock_irqrestore(&mfp_spin_lock, flags);
264 }
265
mfp_config_lpm(void)266 void mfp_config_lpm(void)
267 {
268 struct mfp_pin *p = &mfp_table[0];
269 int pin;
270
271 for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
272 __mfp_config_lpm(p);
273 }
274
mfp_config_run(void)275 void mfp_config_run(void)
276 {
277 struct mfp_pin *p = &mfp_table[0];
278 int pin;
279
280 for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
281 __mfp_config_run(p);
282 }
283