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) 143 144 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 } 149 150 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 } 160 161 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 } 203 204 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 } 216 217 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 } 228 229 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 } 239 240 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 } 265 266 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 } 274 275 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