arch/arm/mach-ixp2000/core.c

   1 /*
   2  * arch/arm/mach-ixp2000/common.c
   3  *
   4  * Common routines used by all IXP2400/2800 based platforms.
   5  *
   6  * Author: Deepak Saxena <dsaxena@plexity.net>
   7  *
   8  * Copyright 2004 (C) MontaVista Software, Inc.
   9  *
  10  * Based on work Copyright (C) 2002-2003 Intel Corporation
  11  *
  12  * This file is licensed under the terms of the GNU General Public
  13  * License version 2. This program is licensed "as is" without any
  14  * warranty of any kind, whether express or implied.
  15  */
  16
  17 #include <linux/config.h>
  18 #include <linux/kernel.h>
  19 #include <linux/init.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/sched.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/serial.h>
  24 #include <linux/tty.h>
  25 #include <linux/bitops.h>
  26 #include <linux/serial_core.h>
  27 #include <linux/mm.h>
  28
  29 #include <asm/types.h>
  30 #include <asm/setup.h>
  31 #include <asm/memory.h>
  32 #include <asm/hardware.h>
  33 #include <asm/mach-types.h>
  34 #include <asm/irq.h>
  35 #include <asm/system.h>
  36 #include <asm/tlbflush.h>
  37 #include <asm/pgtable.h>
  38
  39 #include <asm/mach/map.h>
  40 #include <asm/mach/time.h>
  41 #include <asm/mach/irq.h>
  42
  43 #include <asm/arch/gpio.h>
  44
  45 static DEFINE_SPINLOCK(ixp2000_slowport_lock);
  46 static unsigned long ixp2000_slowport_irq_flags;
  47
  48 /*************************************************************************
  49  * Slowport access routines
  50  *************************************************************************/
  51 void ixp2000_acquire_slowport(struct slowport_cfg *new_cfg, struct slowport_cfg *old_cfg)
  52 {
  53
  54         spin_lock_irqsave(&ixp2000_slowport_lock, ixp2000_slowport_irq_flags);
  55
  56         old_cfg->CCR = *IXP2000_SLOWPORT_CCR;
  57         old_cfg->WTC = *IXP2000_SLOWPORT_WTC2;
  58         old_cfg->RTC = *IXP2000_SLOWPORT_RTC2;
  59         old_cfg->PCR = *IXP2000_SLOWPORT_PCR;
  60         old_cfg->ADC = *IXP2000_SLOWPORT_ADC;
  61
  62         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, new_cfg->CCR);
  63         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, new_cfg->WTC);
  64         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, new_cfg->RTC);
  65         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, new_cfg->PCR);
  66         ixp2000_reg_write(IXP2000_SLOWPORT_ADC, new_cfg->ADC);
  67 }
  68
  69 void ixp2000_release_slowport(struct slowport_cfg *old_cfg)
  70 {
  71         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, old_cfg->CCR);
  72         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, old_cfg->WTC);
  73         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, old_cfg->RTC);
  74         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, old_cfg->PCR);
  75         ixp2000_reg_write(IXP2000_SLOWPORT_ADC, old_cfg->ADC);
  76
  77         spin_unlock_irqrestore(&ixp2000_slowport_lock,
  78                                         ixp2000_slowport_irq_flags);
  79 }
  80
  81 /*************************************************************************
  82  * Chip specific mappings shared by all IXP2000 systems
  83  *************************************************************************/
  84 static struct map_desc ixp2000_io_desc[] __initdata = {
  85         {
  86                 .virtual        = IXP2000_CAP_VIRT_BASE,
  87                 .physical       = IXP2000_CAP_PHYS_BASE,
  88                 .length         = IXP2000_CAP_SIZE,
  89                 .type           = MT_DEVICE
  90         }, {
  91                 .virtual        = IXP2000_INTCTL_VIRT_BASE,
  92                 .physical       = IXP2000_INTCTL_PHYS_BASE,
  93                 .length         = IXP2000_INTCTL_SIZE,
  94                 .type           = MT_DEVICE
  95         }, {
  96                 .virtual        = IXP2000_PCI_CREG_VIRT_BASE,
  97                 .physical       = IXP2000_PCI_CREG_PHYS_BASE,
  98                 .length         = IXP2000_PCI_CREG_SIZE,
  99                 .type           = MT_DEVICE
 100         }, {
 101                 .virtual        = IXP2000_PCI_CSR_VIRT_BASE,
 102                 .physical       = IXP2000_PCI_CSR_PHYS_BASE,
 103                 .length         = IXP2000_PCI_CSR_SIZE,
 104                 .type           = MT_DEVICE
 105         }, {
 106                 .virtual        = IXP2000_MSF_VIRT_BASE,
 107                 .physical       = IXP2000_MSF_PHYS_BASE,
 108                 .length         = IXP2000_MSF_SIZE,
 109                 .type           = MT_DEVICE
 110         }, {
 111                 .virtual        = IXP2000_PCI_IO_VIRT_BASE,
 112                 .physical       = IXP2000_PCI_IO_PHYS_BASE,
 113                 .length         = IXP2000_PCI_IO_SIZE,
 114                 .type           = MT_DEVICE
 115         }, {
 116                 .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
 117                 .physical       = IXP2000_PCI_CFG0_PHYS_BASE,
 118                 .length         = IXP2000_PCI_CFG0_SIZE,
 119                 .type           = MT_DEVICE
 120         }, {
 121                 .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
 122                 .physical       = IXP2000_PCI_CFG1_PHYS_BASE,
 123                 .length         = IXP2000_PCI_CFG1_SIZE,
 124                 .type           = MT_DEVICE
 125         }
 126 };
 127
 128 static struct uart_port ixp2000_serial_port = {
 129         .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
 130         .mapbase        = IXP2000_UART_PHYS_BASE + 3,
 131         .irq            = IRQ_IXP2000_UART,
 132         .flags          = UPF_SKIP_TEST,
 133         .iotype         = UPIO_MEM,
 134         .regshift       = 2,
 135         .uartclk        = 50000000,
 136         .line           = 0,
 137         .type           = PORT_XSCALE,
 138         .fifosize       = 16
 139 };
 140
 141 void __init ixp2000_map_io(void)
 142 {
 143         extern unsigned int processor_id;
 144
 145         /*
 146          * On IXP2400 CPUs we need to use MT_IXP2000_DEVICE for
 147          * tweaking the PMDs so XCB=101. On IXP2800s we use the normal
 148          * PMD flags.
 149          */
 150         if ((processor_id & 0xfffffff0) == 0x69054190) {
 151                 int i;
 152
 153                 printk(KERN_INFO "Enabling IXP2400 erratum #66 workaround\n");
 154
 155                 for(i=0;i<ARRAY_SIZE(ixp2000_io_desc);i++)
 156                         ixp2000_io_desc[i].type = MT_IXP2000_DEVICE;
 157         }
 158
 159         iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
 160         early_serial_setup(&ixp2000_serial_port);
 161
 162         /* Set slowport to 8-bit mode.  */
 163         ixp2000_reg_write(IXP2000_SLOWPORT_FRM, 1);
 164 }
 165
 166 /*************************************************************************
 167  * Timer-tick functions for IXP2000
 168  *************************************************************************/
 169 static unsigned ticks_per_jiffy;
 170 static unsigned ticks_per_usec;
 171 static unsigned next_jiffy_time;
 172 static volatile unsigned long *missing_jiffy_timer_csr;
 173
 174 unsigned long ixp2000_gettimeoffset (void)
 175 {
 176         unsigned long offset;
 177
 178         offset = next_jiffy_time - *missing_jiffy_timer_csr;
 179
 180         return offset / ticks_per_usec;
 181 }
 182
 183 static int ixp2000_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 184 {
 185         write_seqlock(&xtime_lock);
 186
 187         /* clear timer 1 */
 188         ixp2000_reg_write(IXP2000_T1_CLR, 1);
 189
 190         while ((next_jiffy_time - *missing_jiffy_timer_csr) > ticks_per_jiffy) {
 191                 timer_tick(regs);
 192                 next_jiffy_time -= ticks_per_jiffy;
 193         }
 194
 195         write_sequnlock(&xtime_lock);
 196
 197         return IRQ_HANDLED;
 198 }
 199
 200 static struct irqaction ixp2000_timer_irq = {
 201         .name           = "IXP2000 Timer Tick",
 202         .flags          = SA_INTERRUPT | SA_TIMER,
 203         .handler        = ixp2000_timer_interrupt,
 204 };
 205
 206 void __init ixp2000_init_time(unsigned long tick_rate)
 207 {
 208         ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
 209         ticks_per_usec = tick_rate / 1000000;
 210
 211         /*
 212          * We use timer 1 as our timer interrupt.
 213          */
 214         ixp2000_reg_write(IXP2000_T1_CLR, 0);
 215         ixp2000_reg_write(IXP2000_T1_CLD, ticks_per_jiffy - 1);
 216         ixp2000_reg_write(IXP2000_T1_CTL, (1 << 7));
 217
 218         /*
 219          * We use a second timer as a monotonic counter for tracking
 220          * missed jiffies.  The IXP2000 has four timers, but if we're
 221          * on an A-step IXP2800, timer 2 and 3 don't work, so on those
 222          * chips we use timer 4.  Timer 4 is the only timer that can
 223          * be used for the watchdog, so we use timer 2 if we're on a
 224          * non-buggy chip.
 225          */
 226         if ((*IXP2000_PRODUCT_ID & 0x001ffef0) == 0x00000000) {
 227                 printk(KERN_INFO "Enabling IXP2800 erratum #25 workaround\n");
 228
 229                 ixp2000_reg_write(IXP2000_T4_CLR, 0);
 230                 ixp2000_reg_write(IXP2000_T4_CLD, -1);
 231                 ixp2000_reg_write(IXP2000_T4_CTL, (1 << 7));
 232                 missing_jiffy_timer_csr = IXP2000_T4_CSR;
 233         } else {
 234                 ixp2000_reg_write(IXP2000_T2_CLR, 0);
 235                 ixp2000_reg_write(IXP2000_T2_CLD, -1);
 236                 ixp2000_reg_write(IXP2000_T2_CTL, (1 << 7));
 237                 missing_jiffy_timer_csr = IXP2000_T2_CSR;
 238         }
 239         next_jiffy_time = 0xffffffff;
 240
 241         /* register for interrupt */
 242         setup_irq(IRQ_IXP2000_TIMER1, &ixp2000_timer_irq);
 243 }
 244
 245 /*************************************************************************
 246  * GPIO helpers
 247  *************************************************************************/
 248 static unsigned long GPIO_IRQ_falling_edge;
 249 static unsigned long GPIO_IRQ_rising_edge;
 250 static unsigned long GPIO_IRQ_level_low;
 251 static unsigned long GPIO_IRQ_level_high;
 252
 253 static void update_gpio_int_csrs(void)
 254 {
 255         ixp2000_reg_write(IXP2000_GPIO_FEDR, GPIO_IRQ_falling_edge);
 256         ixp2000_reg_write(IXP2000_GPIO_REDR, GPIO_IRQ_rising_edge);
 257         ixp2000_reg_write(IXP2000_GPIO_LSLR, GPIO_IRQ_level_low);
 258         ixp2000_reg_write(IXP2000_GPIO_LSHR, GPIO_IRQ_level_high);
 259 }
 260
 261 void gpio_line_config(int line, int direction)
 262 {
 263         unsigned long flags;
 264
 265         local_irq_save(flags);
 266         if (direction == GPIO_OUT) {
 267                 irq_desc[line + IRQ_IXP2000_GPIO0].valid = 0;
 268
 269                 /* if it's an output, it ain't an interrupt anymore */
 270                 GPIO_IRQ_falling_edge &= ~(1 << line);
 271                 GPIO_IRQ_rising_edge &= ~(1 << line);
 272                 GPIO_IRQ_level_low &= ~(1 << line);
 273                 GPIO_IRQ_level_high &= ~(1 << line);
 274                 update_gpio_int_csrs();
 275
 276                 ixp2000_reg_write(IXP2000_GPIO_PDSR, 1 << line);
 277         } else if (direction == GPIO_IN) {
 278                 ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
 279         }
 280         local_irq_restore(flags);
 281 }
 282
 283
 284 /*************************************************************************
 285  * IRQ handling IXP2000
 286  *************************************************************************/
 287 static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
 288 {
 289         int i;
 290         unsigned long status = *IXP2000_GPIO_INST;
 291
 292         for (i = 0; i <= 7; i++) {
 293                 if (status & (1<<i)) {
 294                         desc = irq_desc + i + IRQ_IXP2000_GPIO0;
 295                         desc->handle(i + IRQ_IXP2000_GPIO0, desc, regs);
 296                 }
 297         }
 298 }
 299
 300 static int ixp2000_GPIO_irq_type(unsigned int irq, unsigned int type)
 301 {
 302         int line = irq - IRQ_IXP2000_GPIO0;
 303
 304         /*
 305          * First, configure this GPIO line as an input.
 306          */
 307         ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
 308
 309         /*
 310          * Then, set the proper trigger type.
 311          */
 312         if (type & IRQT_FALLING)
 313                 GPIO_IRQ_falling_edge |= 1 << line;
 314         else
 315                 GPIO_IRQ_falling_edge &= ~(1 << line);
 316         if (type & IRQT_RISING)
 317                 GPIO_IRQ_rising_edge |= 1 << line;
 318         else
 319                 GPIO_IRQ_rising_edge &= ~(1 << line);
 320         if (type & IRQT_LOW)
 321                 GPIO_IRQ_level_low |= 1 << line;
 322         else
 323                 GPIO_IRQ_level_low &= ~(1 << line);
 324         if (type & IRQT_HIGH)
 325                 GPIO_IRQ_level_high |= 1 << line;
 326         else
 327                 GPIO_IRQ_level_high &= ~(1 << line);
 328         update_gpio_int_csrs();
 329
 330         /*
 331          * Finally, mark the corresponding IRQ as valid.
 332          */
 333         irq_desc[irq].valid = 1;
 334
 335         return 0;
 336 }
 337
 338 static void ixp2000_GPIO_irq_mask_ack(unsigned int irq)
 339 {
 340         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 341
 342         ixp2000_reg_write(IXP2000_GPIO_EDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 343         ixp2000_reg_write(IXP2000_GPIO_LDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 344         ixp2000_reg_write(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
 345 }
 346
 347 static void ixp2000_GPIO_irq_mask(unsigned int irq)
 348 {
 349         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 350 }
 351
 352 static void ixp2000_GPIO_irq_unmask(unsigned int irq)
 353 {
 354         ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 355 }
 356
 357 static struct irqchip ixp2000_GPIO_irq_chip = {
 358         .type   = ixp2000_GPIO_irq_type,
 359         .ack    = ixp2000_GPIO_irq_mask_ack,
 360         .mask   = ixp2000_GPIO_irq_mask,
 361         .unmask = ixp2000_GPIO_irq_unmask
 362 };
 363
 364 static void ixp2000_pci_irq_mask(unsigned int irq)
 365 {
 366         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 367         if (irq == IRQ_IXP2000_PCIA)
 368                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
 369         else if (irq == IRQ_IXP2000_PCIB)
 370                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 27)));
 371 }
 372
 373 static void ixp2000_pci_irq_unmask(unsigned int irq)
 374 {
 375         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 376         if (irq == IRQ_IXP2000_PCIA)
 377                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
 378         else if (irq == IRQ_IXP2000_PCIB)
 379                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 27)));
 380 }
 381
 382 static struct irqchip ixp2000_pci_irq_chip = {
 383         .ack    = ixp2000_pci_irq_mask,
 384         .mask   = ixp2000_pci_irq_mask,
 385         .unmask = ixp2000_pci_irq_unmask
 386 };
 387
 388 static void ixp2000_irq_mask(unsigned int irq)
 389 {
 390         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
 391 }
 392
 393 static void ixp2000_irq_unmask(unsigned int irq)
 394 {
 395         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << irq));
 396 }
 397
 398 static struct irqchip ixp2000_irq_chip = {
 399         .ack    = ixp2000_irq_mask,
 400         .mask   = ixp2000_irq_mask,
 401         .unmask = ixp2000_irq_unmask
 402 };
 403
 404 void __init ixp2000_init_irq(void)
 405 {
 406         int irq;
 407
 408         /*
 409          * Mask all sources
 410          */
 411         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
 412         ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
 413
 414         /* clear all GPIO edge/level detects */
 415         ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
 416         ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
 417         ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
 418         ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
 419         ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
 420
 421         /* clear PCI interrupt sources */
 422         ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
 423
 424         /*
 425          * Certain bits in the IRQ status register of the
 426          * IXP2000 are reserved. Instead of trying to map
 427          * things non 1:1 from bit position to IRQ number,
 428          * we mark the reserved IRQs as invalid. This makes
 429          * our mask/unmask code much simpler.
 430          */
 431         for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
 432                 if ((1 << irq) & IXP2000_VALID_IRQ_MASK) {
 433                         set_irq_chip(irq, &ixp2000_irq_chip);
 434                         set_irq_handler(irq, do_level_IRQ);
 435                         set_irq_flags(irq, IRQF_VALID);
 436                 } else set_irq_flags(irq, 0);
 437         }
 438
 439         /*
 440          * GPIO IRQs are invalid until someone sets the interrupt mode
 441          * by calling set_irq_type().
 442          */
 443         for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
 444                 set_irq_chip(irq, &ixp2000_GPIO_irq_chip);
 445                 set_irq_handler(irq, do_level_IRQ);
 446                 set_irq_flags(irq, 0);
 447         }
 448         set_irq_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
 449
 450         /*
 451          * Enable PCI irqs.  The actual PCI[AB] decoding is done in
 452          * entry-macro.S, so we don't need a chained handler for the
 453          * PCI interrupt source.
 454          */
 455         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
 456         for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
 457                 set_irq_chip(irq, &ixp2000_pci_irq_chip);
 458                 set_irq_handler(irq, do_level_IRQ);
 459                 set_irq_flags(irq, IRQF_VALID);
 460         }
 461 }
 462