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   1 /*
   2  *  linux/arch/arm/mach-realview/core.c
   3  *
   4  *  Copyright (C) 1999 - 2003 ARM Limited
   5  *  Copyright (C) 2000 Deep Blue Solutions Ltd
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21 #include <linux/init.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/dma-mapping.h>
  24 #include <linux/sysdev.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/amba/bus.h>
  27 #include <linux/amba/clcd.h>
  28 #include <linux/clocksource.h>
  29 #include <linux/clockchips.h>
  30 #include <linux/io.h>
  31 #include <linux/smc911x.h>
  32
  33 #include <asm/clkdev.h>
  34 #include <asm/system.h>
  35 #include <mach/hardware.h>
  36 #include <asm/irq.h>
  37 #include <asm/leds.h>
  38 #include <asm/mach-types.h>
  39 #include <asm/hardware/arm_timer.h>
  40 #include <asm/hardware/icst307.h>
  41
  42 #include <asm/mach/arch.h>
  43 #include <asm/mach/flash.h>
  44 #include <asm/mach/irq.h>
  45 #include <asm/mach/map.h>
  46 #include <asm/mach/mmc.h>
  47
  48 #include <asm/hardware/gic.h>
  49
  50 #include "core.h"
  51 #include "clock.h"
  52
  53 #define REALVIEW_REFCOUNTER     (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_24MHz_OFFSET)
  54
  55 /* used by entry-macro.S and platsmp.c */
  56 void __iomem *gic_cpu_base_addr;
  57
  58 /*
  59  * This is the RealView sched_clock implementation.  This has
  60  * a resolution of 41.7ns, and a maximum value of about 179s.
  61  */
  62 unsigned long long sched_clock(void)
  63 {
  64         unsigned long long v;
  65
  66         v = (unsigned long long)readl(REALVIEW_REFCOUNTER) * 125;
  67         do_div(v, 3);
  68
  69         return v;
  70 }
  71
  72
  73 #define REALVIEW_FLASHCTRL    (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_FLASH_OFFSET)
  74
  75 static int realview_flash_init(void)
  76 {
  77         u32 val;
  78
  79         val = __raw_readl(REALVIEW_FLASHCTRL);
  80         val &= ~REALVIEW_FLASHPROG_FLVPPEN;
  81         __raw_writel(val, REALVIEW_FLASHCTRL);
  82
  83         return 0;
  84 }
  85
  86 static void realview_flash_exit(void)
  87 {
  88         u32 val;
  89
  90         val = __raw_readl(REALVIEW_FLASHCTRL);
  91         val &= ~REALVIEW_FLASHPROG_FLVPPEN;
  92         __raw_writel(val, REALVIEW_FLASHCTRL);
  93 }
  94
  95 static void realview_flash_set_vpp(int on)
  96 {
  97         u32 val;
  98
  99         val = __raw_readl(REALVIEW_FLASHCTRL);
 100         if (on)
 101                 val |= REALVIEW_FLASHPROG_FLVPPEN;
 102         else
 103                 val &= ~REALVIEW_FLASHPROG_FLVPPEN;
 104         __raw_writel(val, REALVIEW_FLASHCTRL);
 105 }
 106
 107 static struct flash_platform_data realview_flash_data = {
 108         .map_name               = "cfi_probe",
 109         .width                  = 4,
 110         .init                   = realview_flash_init,
 111         .exit                   = realview_flash_exit,
 112         .set_vpp                = realview_flash_set_vpp,
 113 };
 114
 115 struct platform_device realview_flash_device = {
 116         .name                   = "armflash",
 117         .id                     = 0,
 118         .dev                    = {
 119                 .platform_data  = &realview_flash_data,
 120         },
 121 };
 122
 123 int realview_flash_register(struct resource *res, u32 num)
 124 {
 125         realview_flash_device.resource = res;
 126         realview_flash_device.num_resources = num;
 127         return platform_device_register(&realview_flash_device);
 128 }
 129
 130 static struct smc911x_platdata realview_smc911x_platdata = {
 131         .flags          = SMC911X_USE_32BIT,
 132         .irq_flags      = IRQF_SHARED,
 133         .irq_polarity   = 1,
 134 };
 135
 136 static struct platform_device realview_eth_device = {
 137         .name           = "smc911x",
 138         .id             = 0,
 139         .num_resources  = 2,
 140 };
 141
 142 int realview_eth_register(const char *name, struct resource *res)
 143 {
 144         if (name)
 145                 realview_eth_device.name = name;
 146         realview_eth_device.resource = res;
 147         if (strcmp(realview_eth_device.name, "smc911x") == 0)
 148                 realview_eth_device.dev.platform_data = &realview_smc911x_platdata;
 149
 150         return platform_device_register(&realview_eth_device);
 151 }
 152
 153 static struct resource realview_i2c_resource = {
 154         .start          = REALVIEW_I2C_BASE,
 155         .end            = REALVIEW_I2C_BASE + SZ_4K - 1,
 156         .flags          = IORESOURCE_MEM,
 157 };
 158
 159 struct platform_device realview_i2c_device = {
 160         .name           = "versatile-i2c",
 161         .id             = -1,
 162         .num_resources  = 1,
 163         .resource       = &realview_i2c_resource,
 164 };
 165
 166 #define REALVIEW_SYSMCI (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_MCI_OFFSET)
 167
 168 static unsigned int realview_mmc_status(struct device *dev)
 169 {
 170         struct amba_device *adev = container_of(dev, struct amba_device, dev);
 171         u32 mask;
 172
 173         if (adev->res.start == REALVIEW_MMCI0_BASE)
 174                 mask = 1;
 175         else
 176                 mask = 2;
 177
 178         return readl(REALVIEW_SYSMCI) & mask;
 179 }
 180
 181 struct mmc_platform_data realview_mmc0_plat_data = {
 182         .ocr_mask       = MMC_VDD_32_33|MMC_VDD_33_34,
 183         .status         = realview_mmc_status,
 184 };
 185
 186 struct mmc_platform_data realview_mmc1_plat_data = {
 187         .ocr_mask       = MMC_VDD_32_33|MMC_VDD_33_34,
 188         .status         = realview_mmc_status,
 189 };
 190
 191 /*
 192  * Clock handling
 193  */
 194 static const struct icst307_params realview_oscvco_params = {
 195         .ref            = 24000,
 196         .vco_max        = 200000,
 197         .vd_min         = 4 + 8,
 198         .vd_max         = 511 + 8,
 199         .rd_min         = 1 + 2,
 200         .rd_max         = 127 + 2,
 201 };
 202
 203 static void realview_oscvco_set(struct clk *clk, struct icst307_vco vco)
 204 {
 205         void __iomem *sys_lock = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_LOCK_OFFSET;
 206         void __iomem *sys_osc;
 207         u32 val;
 208
 209         if (machine_is_realview_pb1176())
 210                 sys_osc = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_OSC0_OFFSET;
 211         else
 212                 sys_osc = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_OSC4_OFFSET;
 213
 214         val = readl(sys_osc) & ~0x7ffff;
 215         val |= vco.v | (vco.r << 9) | (vco.s << 16);
 216
 217         writel(0xa05f, sys_lock);
 218         writel(val, sys_osc);
 219         writel(0, sys_lock);
 220 }
 221
 222 static struct clk oscvco_clk = {
 223         .params = &realview_oscvco_params,
 224         .setvco = realview_oscvco_set,
 225 };
 226
 227 /*
 228  * These are fixed clocks.
 229  */
 230 static struct clk ref24_clk = {
 231         .rate   = 24000000,
 232 };
 233
 234 static struct clk_lookup lookups[] = {
 235         {       /* UART0 */
 236                 .dev_id         = "dev:f1",
 237                 .clk            = &ref24_clk,
 238         }, {    /* UART1 */
 239                 .dev_id         = "dev:f2",
 240                 .clk            = &ref24_clk,
 241         }, {    /* UART2 */
 242                 .dev_id         = "dev:f3",
 243                 .clk            = &ref24_clk,
 244         }, {    /* UART3 */
 245                 .dev_id         = "fpga:09",
 246                 .clk            = &ref24_clk,
 247         }, {    /* KMI0 */
 248                 .dev_id         = "fpga:06",
 249                 .clk            = &ref24_clk,
 250         }, {    /* KMI1 */
 251                 .dev_id         = "fpga:07",
 252                 .clk            = &ref24_clk,
 253         }, {    /* MMC0 */
 254                 .dev_id         = "fpga:05",
 255                 .clk            = &ref24_clk,
 256         }, {    /* EB:CLCD */
 257                 .dev_id         = "dev:20",
 258                 .clk            = &oscvco_clk,
 259         }, {    /* PB:CLCD */
 260                 .dev_id         = "issp:20",
 261                 .clk            = &oscvco_clk,
 262         }
 263 };
 264
 265 static int __init clk_init(void)
 266 {
 267         int i;
 268
 269         for (i = 0; i < ARRAY_SIZE(lookups); i++)
 270                 clkdev_add(&lookups[i]);
 271         return 0;
 272 }
 273 arch_initcall(clk_init);
 274
 275 /*
 276  * CLCD support.
 277  */
 278 #define SYS_CLCD_NLCDIOON       (1 << 2)
 279 #define SYS_CLCD_VDDPOSSWITCH   (1 << 3)
 280 #define SYS_CLCD_PWR3V5SWITCH   (1 << 4)
 281 #define SYS_CLCD_ID_MASK        (0x1f << 8)
 282 #define SYS_CLCD_ID_SANYO_3_8   (0x00 << 8)
 283 #define SYS_CLCD_ID_UNKNOWN_8_4 (0x01 << 8)
 284 #define SYS_CLCD_ID_EPSON_2_2   (0x02 << 8)
 285 #define SYS_CLCD_ID_SANYO_2_5   (0x07 << 8)
 286 #define SYS_CLCD_ID_VGA         (0x1f << 8)
 287
 288 static struct clcd_panel vga = {
 289         .mode           = {
 290                 .name           = "VGA",
 291                 .refresh        = 60,
 292                 .xres           = 640,
 293                 .yres           = 480,
 294                 .pixclock       = 39721,
 295                 .left_margin    = 40,
 296                 .right_margin   = 24,
 297                 .upper_margin   = 32,
 298                 .lower_margin   = 11,
 299                 .hsync_len      = 96,
 300                 .vsync_len      = 2,
 301                 .sync           = 0,
 302                 .vmode          = FB_VMODE_NONINTERLACED,
 303         },
 304         .width          = -1,
 305         .height         = -1,
 306         .tim2           = TIM2_BCD | TIM2_IPC,
 307         .cntl           = CNTL_LCDTFT | CNTL_BGR | CNTL_LCDVCOMP(1),
 308         .bpp            = 16,
 309 };
 310
 311 static struct clcd_panel xvga = {
 312         .mode           = {
 313                 .name           = "XVGA",
 314                 .refresh        = 60,
 315                 .xres           = 1024,
 316                 .yres           = 768,
 317                 .pixclock       = 15748,
 318                 .left_margin    = 152,
 319                 .right_margin   = 48,
 320                 .upper_margin   = 23,
 321                 .lower_margin   = 3,
 322                 .hsync_len      = 104,
 323                 .vsync_len      = 4,
 324                 .sync           = 0,
 325                 .vmode          = FB_VMODE_NONINTERLACED,
 326         },
 327         .width          = -1,
 328         .height         = -1,
 329         .tim2           = TIM2_BCD | TIM2_IPC,
 330         .cntl           = CNTL_LCDTFT | CNTL_BGR | CNTL_LCDVCOMP(1),
 331         .bpp            = 16,
 332 };
 333
 334 static struct clcd_panel sanyo_3_8_in = {
 335         .mode           = {
 336                 .name           = "Sanyo QVGA",
 337                 .refresh        = 116,
 338                 .xres           = 320,
 339                 .yres           = 240,
 340                 .pixclock       = 100000,
 341                 .left_margin    = 6,
 342                 .right_margin   = 6,
 343                 .upper_margin   = 5,
 344                 .lower_margin   = 5,
 345                 .hsync_len      = 6,
 346                 .vsync_len      = 6,
 347                 .sync           = 0,
 348                 .vmode          = FB_VMODE_NONINTERLACED,
 349         },
 350         .width          = -1,
 351         .height         = -1,
 352         .tim2           = TIM2_BCD,
 353         .cntl           = CNTL_LCDTFT | CNTL_BGR | CNTL_LCDVCOMP(1),
 354         .bpp            = 16,
 355 };
 356
 357 static struct clcd_panel sanyo_2_5_in = {
 358         .mode           = {
 359                 .name           = "Sanyo QVGA Portrait",
 360                 .refresh        = 116,
 361                 .xres           = 240,
 362                 .yres           = 320,
 363                 .pixclock       = 100000,
 364                 .left_margin    = 20,
 365                 .right_margin   = 10,
 366                 .upper_margin   = 2,
 367                 .lower_margin   = 2,
 368                 .hsync_len      = 10,
 369                 .vsync_len      = 2,
 370                 .sync           = FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
 371                 .vmode          = FB_VMODE_NONINTERLACED,
 372         },
 373         .width          = -1,
 374         .height         = -1,
 375         .tim2           = TIM2_IVS | TIM2_IHS | TIM2_IPC,
 376         .cntl           = CNTL_LCDTFT | CNTL_BGR | CNTL_LCDVCOMP(1),
 377         .bpp            = 16,
 378 };
 379
 380 static struct clcd_panel epson_2_2_in = {
 381         .mode           = {
 382                 .name           = "Epson QCIF",
 383                 .refresh        = 390,
 384                 .xres           = 176,
 385                 .yres           = 220,
 386                 .pixclock       = 62500,
 387                 .left_margin    = 3,
 388                 .right_margin   = 2,
 389                 .upper_margin   = 1,
 390                 .lower_margin   = 0,
 391                 .hsync_len      = 3,
 392                 .vsync_len      = 2,
 393                 .sync           = 0,
 394                 .vmode          = FB_VMODE_NONINTERLACED,
 395         },
 396         .width          = -1,
 397         .height         = -1,
 398         .tim2           = TIM2_BCD | TIM2_IPC,
 399         .cntl           = CNTL_LCDTFT | CNTL_BGR | CNTL_LCDVCOMP(1),
 400         .bpp            = 16,
 401 };
 402
 403 /*
 404  * Detect which LCD panel is connected, and return the appropriate
 405  * clcd_panel structure.  Note: we do not have any information on
 406  * the required timings for the 8.4in panel, so we presently assume
 407  * VGA timings.
 408  */
 409 static struct clcd_panel *realview_clcd_panel(void)
 410 {
 411         void __iomem *sys_clcd = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_CLCD_OFFSET;
 412         struct clcd_panel *vga_panel;
 413         struct clcd_panel *panel;
 414         u32 val;
 415
 416         if (machine_is_realview_eb())
 417                 vga_panel = &vga;
 418         else
 419                 vga_panel = &xvga;
 420
 421         val = readl(sys_clcd) & SYS_CLCD_ID_MASK;
 422         if (val == SYS_CLCD_ID_SANYO_3_8)
 423                 panel = &sanyo_3_8_in;
 424         else if (val == SYS_CLCD_ID_SANYO_2_5)
 425                 panel = &sanyo_2_5_in;
 426         else if (val == SYS_CLCD_ID_EPSON_2_2)
 427                 panel = &epson_2_2_in;
 428         else if (val == SYS_CLCD_ID_VGA)
 429                 panel = vga_panel;
 430         else {
 431                 printk(KERN_ERR "CLCD: unknown LCD panel ID 0x%08x, using VGA\n",
 432                         val);
 433                 panel = vga_panel;
 434         }
 435
 436         return panel;
 437 }
 438
 439 /*
 440  * Disable all display connectors on the interface module.
 441  */
 442 static void realview_clcd_disable(struct clcd_fb *fb)
 443 {
 444         void __iomem *sys_clcd = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_CLCD_OFFSET;
 445         u32 val;
 446
 447         val = readl(sys_clcd);
 448         val &= ~SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
 449         writel(val, sys_clcd);
 450 }
 451
 452 /*
 453  * Enable the relevant connector on the interface module.
 454  */
 455 static void realview_clcd_enable(struct clcd_fb *fb)
 456 {
 457         void __iomem *sys_clcd = __io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_CLCD_OFFSET;
 458         u32 val;
 459
 460         /*
 461          * Enable the PSUs
 462          */
 463         val = readl(sys_clcd);
 464         val |= SYS_CLCD_NLCDIOON | SYS_CLCD_PWR3V5SWITCH;
 465         writel(val, sys_clcd);
 466 }
 467
 468 static int realview_clcd_setup(struct clcd_fb *fb)
 469 {
 470         unsigned long framesize;
 471         dma_addr_t dma;
 472
 473         if (machine_is_realview_eb())
 474                 /* VGA, 16bpp */
 475                 framesize = 640 * 480 * 2;
 476         else
 477                 /* XVGA, 16bpp */
 478                 framesize = 1024 * 768 * 2;
 479
 480         fb->panel               = realview_clcd_panel();
 481
 482         fb->fb.screen_base = dma_alloc_writecombine(&fb->dev->dev, framesize,
 483                                                     &dma, GFP_KERNEL);
 484         if (!fb->fb.screen_base) {
 485                 printk(KERN_ERR "CLCD: unable to map framebuffer\n");
 486                 return -ENOMEM;
 487         }
 488
 489         fb->fb.fix.smem_start   = dma;
 490         fb->fb.fix.smem_len     = framesize;
 491
 492         return 0;
 493 }
 494
 495 static int realview_clcd_mmap(struct clcd_fb *fb, struct vm_area_struct *vma)
 496 {
 497         return dma_mmap_writecombine(&fb->dev->dev, vma,
 498                                      fb->fb.screen_base,
 499                                      fb->fb.fix.smem_start,
 500                                      fb->fb.fix.smem_len);
 501 }
 502
 503 static void realview_clcd_remove(struct clcd_fb *fb)
 504 {
 505         dma_free_writecombine(&fb->dev->dev, fb->fb.fix.smem_len,
 506                               fb->fb.screen_base, fb->fb.fix.smem_start);
 507 }
 508
 509 struct clcd_board clcd_plat_data = {
 510         .name           = "RealView",
 511         .check          = clcdfb_check,
 512         .decode         = clcdfb_decode,
 513         .disable        = realview_clcd_disable,
 514         .enable         = realview_clcd_enable,
 515         .setup          = realview_clcd_setup,
 516         .mmap           = realview_clcd_mmap,
 517         .remove         = realview_clcd_remove,
 518 };
 519
 520 #ifdef CONFIG_LEDS
 521 #define VA_LEDS_BASE (__io_address(REALVIEW_SYS_BASE) + REALVIEW_SYS_LED_OFFSET)
 522
 523 void realview_leds_event(led_event_t ledevt)
 524 {
 525         unsigned long flags;
 526         u32 val;
 527
 528         local_irq_save(flags);
 529         val = readl(VA_LEDS_BASE);
 530
 531         switch (ledevt) {
 532         case led_idle_start:
 533                 val = val & ~REALVIEW_SYS_LED0;
 534                 break;
 535
 536         case led_idle_end:
 537                 val = val | REALVIEW_SYS_LED0;
 538                 break;
 539
 540         case led_timer:
 541                 val = val ^ REALVIEW_SYS_LED1;
 542                 break;
 543
 544         case led_halted:
 545                 val = 0;
 546                 break;
 547
 548         default:
 549                 break;
 550         }
 551
 552         writel(val, VA_LEDS_BASE);
 553         local_irq_restore(flags);
 554 }
 555 #endif  /* CONFIG_LEDS */
 556
 557 /*
 558  * Where is the timer (VA)?
 559  */
 560 void __iomem *timer0_va_base;
 561 void __iomem *timer1_va_base;
 562 void __iomem *timer2_va_base;
 563 void __iomem *timer3_va_base;
 564
 565 /*
 566  * How long is the timer interval?
 567  */
 568 #define TIMER_INTERVAL  (TICKS_PER_uSEC * mSEC_10)
 569 #if TIMER_INTERVAL >= 0x100000
 570 #define TIMER_RELOAD    (TIMER_INTERVAL >> 8)
 571 #define TIMER_DIVISOR   (TIMER_CTRL_DIV256)
 572 #define TICKS2USECS(x)  (256 * (x) / TICKS_PER_uSEC)
 573 #elif TIMER_INTERVAL >= 0x10000
 574 #define TIMER_RELOAD    (TIMER_INTERVAL >> 4)           /* Divide by 16 */
 575 #define TIMER_DIVISOR   (TIMER_CTRL_DIV16)
 576 #define TICKS2USECS(x)  (16 * (x) / TICKS_PER_uSEC)
 577 #else
 578 #define TIMER_RELOAD    (TIMER_INTERVAL)
 579 #define TIMER_DIVISOR   (TIMER_CTRL_DIV1)
 580 #define TICKS2USECS(x)  ((x) / TICKS_PER_uSEC)
 581 #endif
 582
 583 static void timer_set_mode(enum clock_event_mode mode,
 584                            struct clock_event_device *clk)
 585 {
 586         unsigned long ctrl;
 587
 588         switch(mode) {
 589         case CLOCK_EVT_MODE_PERIODIC:
 590                 writel(TIMER_RELOAD, timer0_va_base + TIMER_LOAD);
 591
 592                 ctrl = TIMER_CTRL_PERIODIC;
 593                 ctrl |= TIMER_CTRL_32BIT | TIMER_CTRL_IE | TIMER_CTRL_ENABLE;
 594                 break;
 595         case CLOCK_EVT_MODE_ONESHOT:
 596                 /* period set, and timer enabled in 'next_event' hook */
 597                 ctrl = TIMER_CTRL_ONESHOT;
 598                 ctrl |= TIMER_CTRL_32BIT | TIMER_CTRL_IE;
 599                 break;
 600         case CLOCK_EVT_MODE_UNUSED:
 601         case CLOCK_EVT_MODE_SHUTDOWN:
 602         default:
 603                 ctrl = 0;
 604         }
 605
 606         writel(ctrl, timer0_va_base + TIMER_CTRL);
 607 }
 608
 609 static int timer_set_next_event(unsigned long evt,
 610                                 struct clock_event_device *unused)
 611 {
 612         unsigned long ctrl = readl(timer0_va_base + TIMER_CTRL);
 613
 614         writel(evt, timer0_va_base + TIMER_LOAD);
 615         writel(ctrl | TIMER_CTRL_ENABLE, timer0_va_base + TIMER_CTRL);
 616
 617         return 0;
 618 }
 619
 620 static struct clock_event_device timer0_clockevent =     {
 621         .name           = "timer0",
 622         .shift          = 32,
 623         .features       = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
 624         .set_mode       = timer_set_mode,
 625         .set_next_event = timer_set_next_event,
 626         .rating         = 300,
 627         .cpumask        = cpu_all_mask,
 628 };
 629
 630 static void __init realview_clockevents_init(unsigned int timer_irq)
 631 {
 632         timer0_clockevent.irq = timer_irq;
 633         timer0_clockevent.mult =
 634                 div_sc(1000000, NSEC_PER_SEC, timer0_clockevent.shift);
 635         timer0_clockevent.max_delta_ns =
 636                 clockevent_delta2ns(0xffffffff, &timer0_clockevent);
 637         timer0_clockevent.min_delta_ns =
 638                 clockevent_delta2ns(0xf, &timer0_clockevent);
 639
 640         clockevents_register_device(&timer0_clockevent);
 641 }
 642
 643 /*
 644  * IRQ handler for the timer
 645  */
 646 static irqreturn_t realview_timer_interrupt(int irq, void *dev_id)
 647 {
 648         struct clock_event_device *evt = &timer0_clockevent;
 649
 650         /* clear the interrupt */
 651         writel(1, timer0_va_base + TIMER_INTCLR);
 652
 653         evt->event_handler(evt);
 654
 655         return IRQ_HANDLED;
 656 }
 657
 658 static struct irqaction realview_timer_irq = {
 659         .name           = "RealView Timer Tick",
 660         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 661         .handler        = realview_timer_interrupt,
 662 };
 663
 664 static cycle_t realview_get_cycles(void)
 665 {
 666         return ~readl(timer3_va_base + TIMER_VALUE);
 667 }
 668
 669 static struct clocksource clocksource_realview = {
 670         .name   = "timer3",
 671         .rating = 200,
 672         .read   = realview_get_cycles,
 673         .mask   = CLOCKSOURCE_MASK(32),
 674         .shift  = 20,
 675         .flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 676 };
 677
 678 static void __init realview_clocksource_init(void)
 679 {
 680         /* setup timer 0 as free-running clocksource */
 681         writel(0, timer3_va_base + TIMER_CTRL);
 682         writel(0xffffffff, timer3_va_base + TIMER_LOAD);
 683         writel(0xffffffff, timer3_va_base + TIMER_VALUE);
 684         writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
 685                 timer3_va_base + TIMER_CTRL);
 686
 687         clocksource_realview.mult =
 688                 clocksource_khz2mult(1000, clocksource_realview.shift);
 689         clocksource_register(&clocksource_realview);
 690 }
 691
 692 /*
 693  * Set up the clock source and clock events devices
 694  */
 695 void __init realview_timer_init(unsigned int timer_irq)
 696 {
 697         u32 val;
 698
 699 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 700         /*
 701          * The dummy clock device has to be registered before the main device
 702          * so that the latter will broadcast the clock events
 703          */
 704         local_timer_setup();
 705 #endif
 706
 707         /*
 708          * set clock frequency:
 709          *      REALVIEW_REFCLK is 32KHz
 710          *      REALVIEW_TIMCLK is 1MHz
 711          */
 712         val = readl(__io_address(REALVIEW_SCTL_BASE));
 713         writel((REALVIEW_TIMCLK << REALVIEW_TIMER1_EnSel) |
 714                (REALVIEW_TIMCLK << REALVIEW_TIMER2_EnSel) |
 715                (REALVIEW_TIMCLK << REALVIEW_TIMER3_EnSel) |
 716                (REALVIEW_TIMCLK << REALVIEW_TIMER4_EnSel) | val,
 717                __io_address(REALVIEW_SCTL_BASE));
 718
 719         /*
 720          * Initialise to a known state (all timers off)
 721          */
 722         writel(0, timer0_va_base + TIMER_CTRL);
 723         writel(0, timer1_va_base + TIMER_CTRL);
 724         writel(0, timer2_va_base + TIMER_CTRL);
 725         writel(0, timer3_va_base + TIMER_CTRL);
 726
 727         /*
 728          * Make irqs happen for the system timer
 729          */
 730         setup_irq(timer_irq, &realview_timer_irq);
 731
 732         realview_clocksource_init();
 733         realview_clockevents_init(timer_irq);
 734 }