1 /* 2 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org> 3 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org> 4 * Copyright (C) 2009 Florian Fainelli <florian@openwrt.org> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #include <linux/kernel.h> 22 #include <linux/init.h> 23 #include <linux/types.h> 24 #include <linux/module.h> 25 #include <linux/delay.h> 26 #include <linux/gcd.h> 27 #include <linux/io.h> 28 #include <linux/err.h> 29 #include <linux/clk.h> 30 31 #include <asm/addrspace.h> 32 #include <asm/mach-ar7/ar7.h> 33 34 #define BOOT_PLL_SOURCE_MASK 0x3 35 #define CPU_PLL_SOURCE_SHIFT 16 36 #define BUS_PLL_SOURCE_SHIFT 14 37 #define USB_PLL_SOURCE_SHIFT 18 38 #define DSP_PLL_SOURCE_SHIFT 22 39 #define BOOT_PLL_SOURCE_AFE 0 40 #define BOOT_PLL_SOURCE_BUS 0 41 #define BOOT_PLL_SOURCE_REF 1 42 #define BOOT_PLL_SOURCE_XTAL 2 43 #define BOOT_PLL_SOURCE_CPU 3 44 #define BOOT_PLL_BYPASS 0x00000020 45 #define BOOT_PLL_ASYNC_MODE 0x02000000 46 #define BOOT_PLL_2TO1_MODE 0x00008000 47 48 #define TNETD7200_CLOCK_ID_CPU 0 49 #define TNETD7200_CLOCK_ID_DSP 1 50 #define TNETD7200_CLOCK_ID_USB 2 51 52 #define TNETD7200_DEF_CPU_CLK 211000000 53 #define TNETD7200_DEF_DSP_CLK 125000000 54 #define TNETD7200_DEF_USB_CLK 48000000 55 56 struct tnetd7300_clock { 57 u32 ctrl; 58 #define PREDIV_MASK 0x001f0000 59 #define PREDIV_SHIFT 16 60 #define POSTDIV_MASK 0x0000001f 61 u32 unused1[3]; 62 u32 pll; 63 #define MUL_MASK 0x0000f000 64 #define MUL_SHIFT 12 65 #define PLL_MODE_MASK 0x00000001 66 #define PLL_NDIV 0x00000800 67 #define PLL_DIV 0x00000002 68 #define PLL_STATUS 0x00000001 69 u32 unused2[3]; 70 }; 71 72 struct tnetd7300_clocks { 73 struct tnetd7300_clock bus; 74 struct tnetd7300_clock cpu; 75 struct tnetd7300_clock usb; 76 struct tnetd7300_clock dsp; 77 }; 78 79 struct tnetd7200_clock { 80 u32 ctrl; 81 u32 unused1[3]; 82 #define DIVISOR_ENABLE_MASK 0x00008000 83 u32 mul; 84 u32 prediv; 85 u32 postdiv; 86 u32 postdiv2; 87 u32 unused2[6]; 88 u32 cmd; 89 u32 status; 90 u32 cmden; 91 u32 padding[15]; 92 }; 93 94 struct tnetd7200_clocks { 95 struct tnetd7200_clock cpu; 96 struct tnetd7200_clock dsp; 97 struct tnetd7200_clock usb; 98 }; 99 100 static struct clk bus_clk = { 101 .rate = 125000000, 102 }; 103 104 static struct clk cpu_clk = { 105 .rate = 150000000, 106 }; 107 108 static struct clk dsp_clk; 109 static struct clk vbus_clk; 110 111 static void approximate(int base, int target, int *prediv, 112 int *postdiv, int *mul) 113 { 114 int i, j, k, freq, res = target; 115 for (i = 1; i <= 16; i++) 116 for (j = 1; j <= 32; j++) 117 for (k = 1; k <= 32; k++) { 118 freq = abs(base / j * i / k - target); 119 if (freq < res) { 120 res = freq; 121 *mul = i; 122 *prediv = j; 123 *postdiv = k; 124 } 125 } 126 } 127 128 static void calculate(int base, int target, int *prediv, int *postdiv, 129 int *mul) 130 { 131 int tmp_gcd, tmp_base, tmp_freq; 132 133 for (*prediv = 1; *prediv <= 32; (*prediv)++) { 134 tmp_base = base / *prediv; 135 tmp_gcd = gcd(target, tmp_base); 136 *mul = target / tmp_gcd; 137 *postdiv = tmp_base / tmp_gcd; 138 if ((*mul < 1) || (*mul >= 16)) 139 continue; 140 if ((*postdiv > 0) & (*postdiv <= 32)) 141 break; 142 } 143 144 if (base / *prediv * *mul / *postdiv != target) { 145 approximate(base, target, prediv, postdiv, mul); 146 tmp_freq = base / *prediv * *mul / *postdiv; 147 printk(KERN_WARNING 148 "Adjusted requested frequency %d to %d\n", 149 target, tmp_freq); 150 } 151 152 printk(KERN_DEBUG "Clocks: prediv: %d, postdiv: %d, mul: %d\n", 153 *prediv, *postdiv, *mul); 154 } 155 156 static int tnetd7300_dsp_clock(void) 157 { 158 u32 didr1, didr2; 159 u8 rev = ar7_chip_rev(); 160 didr1 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x18)); 161 didr2 = readl((void *)KSEG1ADDR(AR7_REGS_GPIO + 0x1c)); 162 if (didr2 & (1 << 23)) 163 return 0; 164 if ((rev >= 0x23) && (rev != 0x57)) 165 return 250000000; 166 if ((((didr2 & 0x1fff) << 10) | ((didr1 & 0xffc00000) >> 22)) 167 > 4208000) 168 return 250000000; 169 return 0; 170 } 171 172 static int tnetd7300_get_clock(u32 shift, struct tnetd7300_clock *clock, 173 u32 *bootcr, u32 bus_clock) 174 { 175 int product; 176 int base_clock = AR7_REF_CLOCK; 177 u32 ctrl = readl(&clock->ctrl); 178 u32 pll = readl(&clock->pll); 179 int prediv = ((ctrl & PREDIV_MASK) >> PREDIV_SHIFT) + 1; 180 int postdiv = (ctrl & POSTDIV_MASK) + 1; 181 int divisor = prediv * postdiv; 182 int mul = ((pll & MUL_MASK) >> MUL_SHIFT) + 1; 183 184 switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) { 185 case BOOT_PLL_SOURCE_BUS: 186 base_clock = bus_clock; 187 break; 188 case BOOT_PLL_SOURCE_REF: 189 base_clock = AR7_REF_CLOCK; 190 break; 191 case BOOT_PLL_SOURCE_XTAL: 192 base_clock = AR7_XTAL_CLOCK; 193 break; 194 case BOOT_PLL_SOURCE_CPU: 195 base_clock = cpu_clk.rate; 196 break; 197 } 198 199 if (*bootcr & BOOT_PLL_BYPASS) 200 return base_clock / divisor; 201 202 if ((pll & PLL_MODE_MASK) == 0) 203 return (base_clock >> (mul / 16 + 1)) / divisor; 204 205 if ((pll & (PLL_NDIV | PLL_DIV)) == (PLL_NDIV | PLL_DIV)) { 206 product = (mul & 1) ? 207 (base_clock * mul) >> 1 : 208 (base_clock * (mul - 1)) >> 2; 209 return product / divisor; 210 } 211 212 if (mul == 16) 213 return base_clock / divisor; 214 215 return base_clock * mul / divisor; 216 } 217 218 static void tnetd7300_set_clock(u32 shift, struct tnetd7300_clock *clock, 219 u32 *bootcr, u32 frequency) 220 { 221 int prediv, postdiv, mul; 222 int base_clock = bus_clk.rate; 223 224 switch ((*bootcr & (BOOT_PLL_SOURCE_MASK << shift)) >> shift) { 225 case BOOT_PLL_SOURCE_BUS: 226 base_clock = bus_clk.rate; 227 break; 228 case BOOT_PLL_SOURCE_REF: 229 base_clock = AR7_REF_CLOCK; 230 break; 231 case BOOT_PLL_SOURCE_XTAL: 232 base_clock = AR7_XTAL_CLOCK; 233 break; 234 case BOOT_PLL_SOURCE_CPU: 235 base_clock = cpu_clk.rate; 236 break; 237 } 238 239 calculate(base_clock, frequency, &prediv, &postdiv, &mul); 240 241 writel(((prediv - 1) << PREDIV_SHIFT) | (postdiv - 1), &clock->ctrl); 242 mdelay(1); 243 writel(4, &clock->pll); 244 while (readl(&clock->pll) & PLL_STATUS) 245 ; 246 writel(((mul - 1) << MUL_SHIFT) | (0xff << 3) | 0x0e, &clock->pll); 247 mdelay(75); 248 } 249 250 static void __init tnetd7300_init_clocks(void) 251 { 252 u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4); 253 struct tnetd7300_clocks *clocks = 254 ioremap_nocache(UR8_REGS_CLOCKS, 255 sizeof(struct tnetd7300_clocks)); 256 257 bus_clk.rate = tnetd7300_get_clock(BUS_PLL_SOURCE_SHIFT, 258 &clocks->bus, bootcr, AR7_AFE_CLOCK); 259 260 if (*bootcr & BOOT_PLL_ASYNC_MODE) 261 cpu_clk.rate = tnetd7300_get_clock(CPU_PLL_SOURCE_SHIFT, 262 &clocks->cpu, bootcr, AR7_AFE_CLOCK); 263 else 264 cpu_clk.rate = bus_clk.rate; 265 266 if (dsp_clk.rate == 250000000) 267 tnetd7300_set_clock(DSP_PLL_SOURCE_SHIFT, &clocks->dsp, 268 bootcr, dsp_clk.rate); 269 270 iounmap(clocks); 271 iounmap(bootcr); 272 } 273 274 static void tnetd7200_set_clock(int base, struct tnetd7200_clock *clock, 275 int prediv, int postdiv, int postdiv2, int mul, u32 frequency) 276 { 277 printk(KERN_INFO 278 "Clocks: base = %d, frequency = %u, prediv = %d, " 279 "postdiv = %d, postdiv2 = %d, mul = %d\n", 280 base, frequency, prediv, postdiv, postdiv2, mul); 281 282 writel(0, &clock->ctrl); 283 writel(DIVISOR_ENABLE_MASK | ((prediv - 1) & 0x1F), &clock->prediv); 284 writel((mul - 1) & 0xF, &clock->mul); 285 286 while (readl(&clock->status) & 0x1) 287 ; /* nop */ 288 289 writel(DIVISOR_ENABLE_MASK | ((postdiv - 1) & 0x1F), &clock->postdiv); 290 291 writel(readl(&clock->cmden) | 1, &clock->cmden); 292 writel(readl(&clock->cmd) | 1, &clock->cmd); 293 294 while (readl(&clock->status) & 0x1) 295 ; /* nop */ 296 297 writel(DIVISOR_ENABLE_MASK | ((postdiv2 - 1) & 0x1F), &clock->postdiv2); 298 299 writel(readl(&clock->cmden) | 1, &clock->cmden); 300 writel(readl(&clock->cmd) | 1, &clock->cmd); 301 302 while (readl(&clock->status) & 0x1) 303 ; /* nop */ 304 305 writel(readl(&clock->ctrl) | 1, &clock->ctrl); 306 } 307 308 static int tnetd7200_get_clock_base(int clock_id, u32 *bootcr) 309 { 310 if (*bootcr & BOOT_PLL_ASYNC_MODE) 311 /* Async */ 312 switch (clock_id) { 313 case TNETD7200_CLOCK_ID_DSP: 314 return AR7_REF_CLOCK; 315 default: 316 return AR7_AFE_CLOCK; 317 } 318 else 319 /* Sync */ 320 if (*bootcr & BOOT_PLL_2TO1_MODE) 321 /* 2:1 */ 322 switch (clock_id) { 323 case TNETD7200_CLOCK_ID_DSP: 324 return AR7_REF_CLOCK; 325 default: 326 return AR7_AFE_CLOCK; 327 } 328 else 329 /* 1:1 */ 330 return AR7_REF_CLOCK; 331 } 332 333 334 static void __init tnetd7200_init_clocks(void) 335 { 336 u32 *bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4); 337 struct tnetd7200_clocks *clocks = 338 ioremap_nocache(AR7_REGS_CLOCKS, 339 sizeof(struct tnetd7200_clocks)); 340 int cpu_base, cpu_mul, cpu_prediv, cpu_postdiv; 341 int dsp_base, dsp_mul, dsp_prediv, dsp_postdiv; 342 int usb_base, usb_mul, usb_prediv, usb_postdiv; 343 344 cpu_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_CPU, bootcr); 345 dsp_base = tnetd7200_get_clock_base(TNETD7200_CLOCK_ID_DSP, bootcr); 346 347 if (*bootcr & BOOT_PLL_ASYNC_MODE) { 348 printk(KERN_INFO "Clocks: Async mode\n"); 349 350 printk(KERN_INFO "Clocks: Setting DSP clock\n"); 351 calculate(dsp_base, TNETD7200_DEF_DSP_CLK, 352 &dsp_prediv, &dsp_postdiv, &dsp_mul); 353 bus_clk.rate = 354 ((dsp_base / dsp_prediv) * dsp_mul) / dsp_postdiv; 355 tnetd7200_set_clock(dsp_base, &clocks->dsp, 356 dsp_prediv, dsp_postdiv * 2, dsp_postdiv, dsp_mul * 2, 357 bus_clk.rate); 358 359 printk(KERN_INFO "Clocks: Setting CPU clock\n"); 360 calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv, 361 &cpu_postdiv, &cpu_mul); 362 cpu_clk.rate = 363 ((cpu_base / cpu_prediv) * cpu_mul) / cpu_postdiv; 364 tnetd7200_set_clock(cpu_base, &clocks->cpu, 365 cpu_prediv, cpu_postdiv, -1, cpu_mul, 366 cpu_clk.rate); 367 368 } else 369 if (*bootcr & BOOT_PLL_2TO1_MODE) { 370 printk(KERN_INFO "Clocks: Sync 2:1 mode\n"); 371 372 printk(KERN_INFO "Clocks: Setting CPU clock\n"); 373 calculate(cpu_base, TNETD7200_DEF_CPU_CLK, &cpu_prediv, 374 &cpu_postdiv, &cpu_mul); 375 cpu_clk.rate = ((cpu_base / cpu_prediv) * cpu_mul) 376 / cpu_postdiv; 377 tnetd7200_set_clock(cpu_base, &clocks->cpu, 378 cpu_prediv, cpu_postdiv, -1, cpu_mul, 379 cpu_clk.rate); 380 381 printk(KERN_INFO "Clocks: Setting DSP clock\n"); 382 calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv, 383 &dsp_postdiv, &dsp_mul); 384 bus_clk.rate = cpu_clk.rate / 2; 385 tnetd7200_set_clock(dsp_base, &clocks->dsp, 386 dsp_prediv, dsp_postdiv * 2, dsp_postdiv, 387 dsp_mul * 2, bus_clk.rate); 388 } else { 389 printk(KERN_INFO "Clocks: Sync 1:1 mode\n"); 390 391 printk(KERN_INFO "Clocks: Setting DSP clock\n"); 392 calculate(dsp_base, TNETD7200_DEF_DSP_CLK, &dsp_prediv, 393 &dsp_postdiv, &dsp_mul); 394 bus_clk.rate = ((dsp_base / dsp_prediv) * dsp_mul) 395 / dsp_postdiv; 396 tnetd7200_set_clock(dsp_base, &clocks->dsp, 397 dsp_prediv, dsp_postdiv * 2, dsp_postdiv, 398 dsp_mul * 2, bus_clk.rate); 399 400 cpu_clk.rate = bus_clk.rate; 401 } 402 403 printk(KERN_INFO "Clocks: Setting USB clock\n"); 404 usb_base = bus_clk.rate; 405 calculate(usb_base, TNETD7200_DEF_USB_CLK, &usb_prediv, 406 &usb_postdiv, &usb_mul); 407 tnetd7200_set_clock(usb_base, &clocks->usb, 408 usb_prediv, usb_postdiv, -1, usb_mul, 409 TNETD7200_DEF_USB_CLK); 410 411 dsp_clk.rate = cpu_clk.rate; 412 413 iounmap(clocks); 414 iounmap(bootcr); 415 } 416 417 /* 418 * Linux clock API 419 */ 420 int clk_enable(struct clk *clk) 421 { 422 return 0; 423 } 424 EXPORT_SYMBOL(clk_enable); 425 426 void clk_disable(struct clk *clk) 427 { 428 } 429 EXPORT_SYMBOL(clk_disable); 430 431 unsigned long clk_get_rate(struct clk *clk) 432 { 433 return clk->rate; 434 } 435 EXPORT_SYMBOL(clk_get_rate); 436 437 struct clk *clk_get(struct device *dev, const char *id) 438 { 439 if (!strcmp(id, "bus")) 440 return &bus_clk; 441 /* cpmac and vbus share the same rate */ 442 if (!strcmp(id, "cpmac")) 443 return &vbus_clk; 444 if (!strcmp(id, "cpu")) 445 return &cpu_clk; 446 if (!strcmp(id, "dsp")) 447 return &dsp_clk; 448 if (!strcmp(id, "vbus")) 449 return &vbus_clk; 450 return ERR_PTR(-ENOENT); 451 } 452 EXPORT_SYMBOL(clk_get); 453 454 void clk_put(struct clk *clk) 455 { 456 } 457 EXPORT_SYMBOL(clk_put); 458 459 void __init ar7_init_clocks(void) 460 { 461 switch (ar7_chip_id()) { 462 case AR7_CHIP_7100: 463 case AR7_CHIP_7200: 464 tnetd7200_init_clocks(); 465 break; 466 case AR7_CHIP_7300: 467 dsp_clk.rate = tnetd7300_dsp_clock(); 468 tnetd7300_init_clocks(); 469 break; 470 default: 471 break; 472 } 473 /* adjust vbus clock rate */ 474 vbus_clk.rate = bus_clk.rate / 2; 475 } 476