arch/arm/mach-ep93xx/core.c

   1 /*
   2  * arch/arm/mach-ep93xx/core.c
   3  * Core routines for Cirrus EP93xx chips.
   4  *
   5  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
   6  * Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org>
   7  *
   8  * Thanks go to Michael Burian and Ray Lehtiniemi for their key
   9  * role in the ep93xx linux community.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or (at
  14  * your option) any later version.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/sched.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/serial.h>
  23 #include <linux/tty.h>
  24 #include <linux/bitops.h>
  25 #include <linux/serial_8250.h>
  26 #include <linux/serial_core.h>
  27 #include <linux/device.h>
  28 #include <linux/mm.h>
  29 #include <linux/time.h>
  30 #include <linux/timex.h>
  31 #include <linux/delay.h>
  32 #include <linux/termios.h>
  33 #include <linux/amba/bus.h>
  34 #include <linux/amba/serial.h>
  35 #include <linux/io.h>
  36
  37 #include <asm/types.h>
  38 #include <asm/setup.h>
  39 #include <asm/memory.h>
  40 #include <mach/hardware.h>
  41 #include <asm/irq.h>
  42 #include <asm/system.h>
  43 #include <asm/tlbflush.h>
  44 #include <asm/pgtable.h>
  45
  46 #include <asm/mach/map.h>
  47 #include <asm/mach/time.h>
  48 #include <asm/mach/irq.h>
  49 #include <mach/gpio.h>
  50
  51 #include <asm/hardware/vic.h>
  52
  53
  54 /*************************************************************************
  55  * Static I/O mappings that are needed for all EP93xx platforms
  56  *************************************************************************/
  57 static struct map_desc ep93xx_io_desc[] __initdata = {
  58         {
  59                 .virtual        = EP93XX_AHB_VIRT_BASE,
  60                 .pfn            = __phys_to_pfn(EP93XX_AHB_PHYS_BASE),
  61                 .length         = EP93XX_AHB_SIZE,
  62                 .type           = MT_DEVICE,
  63         }, {
  64                 .virtual        = EP93XX_APB_VIRT_BASE,
  65                 .pfn            = __phys_to_pfn(EP93XX_APB_PHYS_BASE),
  66                 .length         = EP93XX_APB_SIZE,
  67                 .type           = MT_DEVICE,
  68         },
  69 };
  70
  71 void __init ep93xx_map_io(void)
  72 {
  73         iotable_init(ep93xx_io_desc, ARRAY_SIZE(ep93xx_io_desc));
  74 }
  75
  76
  77 /*************************************************************************
  78  * Timer handling for EP93xx
  79  *************************************************************************
  80  * The ep93xx has four internal timers.  Timers 1, 2 (both 16 bit) and
  81  * 3 (32 bit) count down at 508 kHz, are self-reloading, and can generate
  82  * an interrupt on underflow.  Timer 4 (40 bit) counts down at 983.04 kHz,
  83  * is free-running, and can't generate interrupts.
  84  *
  85  * The 508 kHz timers are ideal for use for the timer interrupt, as the
  86  * most common values of HZ divide 508 kHz nicely.  We pick one of the 16
  87  * bit timers (timer 1) since we don't need more than 16 bits of reload
  88  * value as long as HZ >= 8.
  89  *
  90  * The higher clock rate of timer 4 makes it a better choice than the
  91  * other timers for use in gettimeoffset(), while the fact that it can't
  92  * generate interrupts means we don't have to worry about not being able
  93  * to use this timer for something else.  We also use timer 4 for keeping
  94  * track of lost jiffies.
  95  */
  96 static unsigned int last_jiffy_time;
  97
  98 #define TIMER4_TICKS_PER_JIFFY          ((CLOCK_TICK_RATE + (HZ/2)) / HZ)
  99
 100 static int ep93xx_timer_interrupt(int irq, void *dev_id)
 101 {
 102         __raw_writel(1, EP93XX_TIMER1_CLEAR);
 103         while ((signed long)
 104                 (__raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time)
 105                                                 >= TIMER4_TICKS_PER_JIFFY) {
 106                 last_jiffy_time += TIMER4_TICKS_PER_JIFFY;
 107                 timer_tick();
 108         }
 109
 110         return IRQ_HANDLED;
 111 }
 112
 113 static struct irqaction ep93xx_timer_irq = {
 114         .name           = "ep93xx timer",
 115         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 116         .handler        = ep93xx_timer_interrupt,
 117 };
 118
 119 static void __init ep93xx_timer_init(void)
 120 {
 121         /* Enable periodic HZ timer.  */
 122         __raw_writel(0x48, EP93XX_TIMER1_CONTROL);
 123         __raw_writel((508469 / HZ) - 1, EP93XX_TIMER1_LOAD);
 124         __raw_writel(0xc8, EP93XX_TIMER1_CONTROL);
 125
 126         /* Enable lost jiffy timer.  */
 127         __raw_writel(0x100, EP93XX_TIMER4_VALUE_HIGH);
 128
 129         setup_irq(IRQ_EP93XX_TIMER1, &ep93xx_timer_irq);
 130 }
 131
 132 static unsigned long ep93xx_gettimeoffset(void)
 133 {
 134         int offset;
 135
 136         offset = __raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time;
 137
 138         /* Calculate (1000000 / 983040) * offset.  */
 139         return offset + (53 * offset / 3072);
 140 }
 141
 142 struct sys_timer ep93xx_timer = {
 143         .init           = ep93xx_timer_init,
 144         .offset         = ep93xx_gettimeoffset,
 145 };
 146
 147
 148 /*************************************************************************
 149  * GPIO handling for EP93xx
 150  *************************************************************************/
 151 static unsigned char gpio_int_unmasked[3];
 152 static unsigned char gpio_int_enabled[3];
 153 static unsigned char gpio_int_type1[3];
 154 static unsigned char gpio_int_type2[3];
 155
 156 /* Port ordering is: A B F */
 157 static const u8 int_type1_register_offset[3]    = { 0x90, 0xac, 0x4c };
 158 static const u8 int_type2_register_offset[3]    = { 0x94, 0xb0, 0x50 };
 159 static const u8 eoi_register_offset[3]          = { 0x98, 0xb4, 0x54 };
 160 static const u8 int_en_register_offset[3]       = { 0x9c, 0xb8, 0x5c };
 161
 162 void ep93xx_gpio_update_int_params(unsigned port)
 163 {
 164         BUG_ON(port > 2);
 165
 166         __raw_writeb(0, EP93XX_GPIO_REG(int_en_register_offset[port]));
 167
 168         __raw_writeb(gpio_int_type2[port],
 169                 EP93XX_GPIO_REG(int_type2_register_offset[port]));
 170
 171         __raw_writeb(gpio_int_type1[port],
 172                 EP93XX_GPIO_REG(int_type1_register_offset[port]));
 173
 174         __raw_writeb(gpio_int_unmasked[port] & gpio_int_enabled[port],
 175                 EP93XX_GPIO_REG(int_en_register_offset[port]));
 176 }
 177
 178 void ep93xx_gpio_int_mask(unsigned line)
 179 {
 180         gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7));
 181 }
 182
 183 /*************************************************************************
 184  * EP93xx IRQ handling
 185  *************************************************************************/
 186 static void ep93xx_gpio_ab_irq_handler(unsigned int irq, struct irq_desc *desc)
 187 {
 188         unsigned char status;
 189         int i;
 190
 191         status = __raw_readb(EP93XX_GPIO_A_INT_STATUS);
 192         for (i = 0; i < 8; i++) {
 193                 if (status & (1 << i)) {
 194                         int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_A(0)) + i;
 195                         desc = irq_desc + gpio_irq;
 196                         desc_handle_irq(gpio_irq, desc);
 197                 }
 198         }
 199
 200         status = __raw_readb(EP93XX_GPIO_B_INT_STATUS);
 201         for (i = 0; i < 8; i++) {
 202                 if (status & (1 << i)) {
 203                         int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_B(0)) + i;
 204                         desc = irq_desc + gpio_irq;
 205                         desc_handle_irq(gpio_irq, desc);
 206                 }
 207         }
 208 }
 209
 210 static void ep93xx_gpio_f_irq_handler(unsigned int irq, struct irq_desc *desc)
 211 {
 212         /*
 213          * map discontiguous hw irq range to continous sw irq range:
 214          *
 215          *  IRQ_EP93XX_GPIO{0..7}MUX -> gpio_to_irq(EP93XX_GPIO_LINE_F({0..7})
 216          */
 217         int port_f_idx = ((irq + 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */
 218         int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_F(0)) + port_f_idx;
 219
 220         desc_handle_irq(gpio_irq, irq_desc + gpio_irq);
 221 }
 222
 223 static void ep93xx_gpio_irq_ack(unsigned int irq)
 224 {
 225         int line = irq_to_gpio(irq);
 226         int port = line >> 3;
 227         int port_mask = 1 << (line & 7);
 228
 229         if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
 230                 gpio_int_type2[port] ^= port_mask; /* switch edge direction */
 231                 ep93xx_gpio_update_int_params(port);
 232         }
 233
 234         __raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port]));
 235 }
 236
 237 static void ep93xx_gpio_irq_mask_ack(unsigned int irq)
 238 {
 239         int line = irq_to_gpio(irq);
 240         int port = line >> 3;
 241         int port_mask = 1 << (line & 7);
 242
 243         if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
 244                 gpio_int_type2[port] ^= port_mask; /* switch edge direction */
 245
 246         gpio_int_unmasked[port] &= ~port_mask;
 247         ep93xx_gpio_update_int_params(port);
 248
 249         __raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port]));
 250 }
 251
 252 static void ep93xx_gpio_irq_mask(unsigned int irq)
 253 {
 254         int line = irq_to_gpio(irq);
 255         int port = line >> 3;
 256
 257         gpio_int_unmasked[port] &= ~(1 << (line & 7));
 258         ep93xx_gpio_update_int_params(port);
 259 }
 260
 261 static void ep93xx_gpio_irq_unmask(unsigned int irq)
 262 {
 263         int line = irq_to_gpio(irq);
 264         int port = line >> 3;
 265
 266         gpio_int_unmasked[port] |= 1 << (line & 7);
 267         ep93xx_gpio_update_int_params(port);
 268 }
 269
 270
 271 /*
 272  * gpio_int_type1 controls whether the interrupt is level (0) or
 273  * edge (1) triggered, while gpio_int_type2 controls whether it
 274  * triggers on low/falling (0) or high/rising (1).
 275  */
 276 static int ep93xx_gpio_irq_type(unsigned int irq, unsigned int type)
 277 {
 278         struct irq_desc *desc = irq_desc + irq;
 279         const int gpio = irq_to_gpio(irq);
 280         const int port = gpio >> 3;
 281         const int port_mask = 1 << (gpio & 7);
 282
 283         gpio_direction_input(gpio);
 284
 285         switch (type) {
 286         case IRQ_TYPE_EDGE_RISING:
 287                 gpio_int_type1[port] |= port_mask;
 288                 gpio_int_type2[port] |= port_mask;
 289                 desc->handle_irq = handle_edge_irq;
 290                 break;
 291         case IRQ_TYPE_EDGE_FALLING:
 292                 gpio_int_type1[port] |= port_mask;
 293                 gpio_int_type2[port] &= ~port_mask;
 294                 desc->handle_irq = handle_edge_irq;
 295                 break;
 296         case IRQ_TYPE_LEVEL_HIGH:
 297                 gpio_int_type1[port] &= ~port_mask;
 298                 gpio_int_type2[port] |= port_mask;
 299                 desc->handle_irq = handle_level_irq;
 300                 break;
 301         case IRQ_TYPE_LEVEL_LOW:
 302                 gpio_int_type1[port] &= ~port_mask;
 303                 gpio_int_type2[port] &= ~port_mask;
 304                 desc->handle_irq = handle_level_irq;
 305                 break;
 306         case IRQ_TYPE_EDGE_BOTH:
 307                 gpio_int_type1[port] |= port_mask;
 308                 /* set initial polarity based on current input level */
 309                 if (gpio_get_value(gpio))
 310                         gpio_int_type2[port] &= ~port_mask; /* falling */
 311                 else
 312                         gpio_int_type2[port] |= port_mask; /* rising */
 313                 desc->handle_irq = handle_edge_irq;
 314                 break;
 315         default:
 316                 pr_err("ep93xx: failed to set irq type %d for gpio %d\n",
 317                        type, gpio);
 318                 return -EINVAL;
 319         }
 320
 321         gpio_int_enabled[port] |= port_mask;
 322
 323         desc->status &= ~IRQ_TYPE_SENSE_MASK;
 324         desc->status |= type & IRQ_TYPE_SENSE_MASK;
 325
 326         ep93xx_gpio_update_int_params(port);
 327
 328         return 0;
 329 }
 330
 331 static struct irq_chip ep93xx_gpio_irq_chip = {
 332         .name           = "GPIO",
 333         .ack            = ep93xx_gpio_irq_ack,
 334         .mask_ack       = ep93xx_gpio_irq_mask_ack,
 335         .mask           = ep93xx_gpio_irq_mask,
 336         .unmask         = ep93xx_gpio_irq_unmask,
 337         .set_type       = ep93xx_gpio_irq_type,
 338 };
 339
 340
 341 void __init ep93xx_init_irq(void)
 342 {
 343         int gpio_irq;
 344
 345         vic_init((void *)EP93XX_VIC1_BASE, 0, EP93XX_VIC1_VALID_IRQ_MASK);
 346         vic_init((void *)EP93XX_VIC2_BASE, 32, EP93XX_VIC2_VALID_IRQ_MASK);
 347
 348         for (gpio_irq = gpio_to_irq(0);
 349              gpio_irq <= gpio_to_irq(EP93XX_GPIO_LINE_MAX_IRQ); ++gpio_irq) {
 350                 set_irq_chip(gpio_irq, &ep93xx_gpio_irq_chip);
 351                 set_irq_handler(gpio_irq, handle_level_irq);
 352                 set_irq_flags(gpio_irq, IRQF_VALID);
 353         }
 354
 355         set_irq_chained_handler(IRQ_EP93XX_GPIO_AB, ep93xx_gpio_ab_irq_handler);
 356         set_irq_chained_handler(IRQ_EP93XX_GPIO0MUX, ep93xx_gpio_f_irq_handler);
 357         set_irq_chained_handler(IRQ_EP93XX_GPIO1MUX, ep93xx_gpio_f_irq_handler);
 358         set_irq_chained_handler(IRQ_EP93XX_GPIO2MUX, ep93xx_gpio_f_irq_handler);
 359         set_irq_chained_handler(IRQ_EP93XX_GPIO3MUX, ep93xx_gpio_f_irq_handler);
 360         set_irq_chained_handler(IRQ_EP93XX_GPIO4MUX, ep93xx_gpio_f_irq_handler);
 361         set_irq_chained_handler(IRQ_EP93XX_GPIO5MUX, ep93xx_gpio_f_irq_handler);
 362         set_irq_chained_handler(IRQ_EP93XX_GPIO6MUX, ep93xx_gpio_f_irq_handler);
 363         set_irq_chained_handler(IRQ_EP93XX_GPIO7MUX, ep93xx_gpio_f_irq_handler);
 364 }
 365
 366
 367 /*************************************************************************
 368  * EP93xx peripheral handling
 369  *************************************************************************/
 370 #define EP93XX_UART_MCR_OFFSET          (0x0100)
 371
 372 static void ep93xx_uart_set_mctrl(struct amba_device *dev,
 373                                   void __iomem *base, unsigned int mctrl)
 374 {
 375         unsigned int mcr;
 376
 377         mcr = 0;
 378         if (!(mctrl & TIOCM_RTS))
 379                 mcr |= 2;
 380         if (!(mctrl & TIOCM_DTR))
 381                 mcr |= 1;
 382
 383         __raw_writel(mcr, base + EP93XX_UART_MCR_OFFSET);
 384 }
 385
 386 static struct amba_pl010_data ep93xx_uart_data = {
 387         .set_mctrl      = ep93xx_uart_set_mctrl,
 388 };
 389
 390 static struct amba_device uart1_device = {
 391         .dev            = {
 392                 .bus_id         = "apb:uart1",
 393                 .platform_data  = &ep93xx_uart_data,
 394         },
 395         .res            = {
 396                 .start  = EP93XX_UART1_PHYS_BASE,
 397                 .end    = EP93XX_UART1_PHYS_BASE + 0x0fff,
 398                 .flags  = IORESOURCE_MEM,
 399         },
 400         .irq            = { IRQ_EP93XX_UART1, NO_IRQ },
 401         .periphid       = 0x00041010,
 402 };
 403
 404 static struct amba_device uart2_device = {
 405         .dev            = {
 406                 .bus_id         = "apb:uart2",
 407                 .platform_data  = &ep93xx_uart_data,
 408         },
 409         .res            = {
 410                 .start  = EP93XX_UART2_PHYS_BASE,
 411                 .end    = EP93XX_UART2_PHYS_BASE + 0x0fff,
 412                 .flags  = IORESOURCE_MEM,
 413         },
 414         .irq            = { IRQ_EP93XX_UART2, NO_IRQ },
 415         .periphid       = 0x00041010,
 416 };
 417
 418 static struct amba_device uart3_device = {
 419         .dev            = {
 420                 .bus_id         = "apb:uart3",
 421                 .platform_data  = &ep93xx_uart_data,
 422         },
 423         .res            = {
 424                 .start  = EP93XX_UART3_PHYS_BASE,
 425                 .end    = EP93XX_UART3_PHYS_BASE + 0x0fff,
 426                 .flags  = IORESOURCE_MEM,
 427         },
 428         .irq            = { IRQ_EP93XX_UART3, NO_IRQ },
 429         .periphid       = 0x00041010,
 430 };
 431
 432
 433 static struct platform_device ep93xx_rtc_device = {
 434        .name           = "ep93xx-rtc",
 435        .id             = -1,
 436        .num_resources  = 0,
 437 };
 438
 439
 440 static struct resource ep93xx_ohci_resources[] = {
 441         [0] = {
 442                 .start  = EP93XX_USB_PHYS_BASE,
 443                 .end    = EP93XX_USB_PHYS_BASE + 0x0fff,
 444                 .flags  = IORESOURCE_MEM,
 445         },
 446         [1] = {
 447                 .start  = IRQ_EP93XX_USB,
 448                 .end    = IRQ_EP93XX_USB,
 449                 .flags  = IORESOURCE_IRQ,
 450         },
 451 };
 452
 453 static struct platform_device ep93xx_ohci_device = {
 454         .name           = "ep93xx-ohci",
 455         .id             = -1,
 456         .dev            = {
 457                 .dma_mask               = (void *)0xffffffff,
 458                 .coherent_dma_mask      = 0xffffffff,
 459         },
 460         .num_resources  = ARRAY_SIZE(ep93xx_ohci_resources),
 461         .resource       = ep93xx_ohci_resources,
 462 };
 463
 464 extern void ep93xx_gpio_init(void);
 465
 466 void __init ep93xx_init_devices(void)
 467 {
 468         unsigned int v;
 469
 470         /*
 471          * Disallow access to MaverickCrunch initially.
 472          */
 473         v = __raw_readl(EP93XX_SYSCON_DEVICE_CONFIG);
 474         v &= ~EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE;
 475         __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK);
 476         __raw_writel(v, EP93XX_SYSCON_DEVICE_CONFIG);
 477
 478         ep93xx_gpio_init();
 479
 480         amba_device_register(&uart1_device, &iomem_resource);
 481         amba_device_register(&uart2_device, &iomem_resource);
 482         amba_device_register(&uart3_device, &iomem_resource);
 483
 484         platform_device_register(&ep93xx_rtc_device);
 485         platform_device_register(&ep93xx_ohci_device);
 486 }