linux/arch/arm/mach-ixp2000/core.c
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   1/*
   2 * arch/arm/mach-ixp2000/core.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/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/irq.h>
  23#include <linux/serial.h>
  24#include <linux/tty.h>
  25#include <linux/bitops.h>
  26#include <linux/serial_8250.h>
  27#include <linux/mm.h>
  28
  29#include <asm/types.h>
  30#include <asm/setup.h>
  31#include <asm/memory.h>
  32#include <mach/hardware.h>
  33#include <asm/irq.h>
  34#include <asm/system.h>
  35#include <asm/tlbflush.h>
  36#include <asm/pgtable.h>
  37
  38#include <asm/mach/map.h>
  39#include <asm/mach/time.h>
  40#include <asm/mach/irq.h>
  41
  42#include <mach/gpio.h>
  43
  44static DEFINE_SPINLOCK(ixp2000_slowport_lock);
  45static unsigned long ixp2000_slowport_irq_flags;
  46
  47/*************************************************************************
  48 * Slowport access routines
  49 *************************************************************************/
  50void ixp2000_acquire_slowport(struct slowport_cfg *new_cfg, struct slowport_cfg *old_cfg)
  51{
  52        spin_lock_irqsave(&ixp2000_slowport_lock, ixp2000_slowport_irq_flags);
  53
  54        old_cfg->CCR = *IXP2000_SLOWPORT_CCR;
  55        old_cfg->WTC = *IXP2000_SLOWPORT_WTC2;
  56        old_cfg->RTC = *IXP2000_SLOWPORT_RTC2;
  57        old_cfg->PCR = *IXP2000_SLOWPORT_PCR;
  58        old_cfg->ADC = *IXP2000_SLOWPORT_ADC;
  59
  60        ixp2000_reg_write(IXP2000_SLOWPORT_CCR, new_cfg->CCR);
  61        ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, new_cfg->WTC);
  62        ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, new_cfg->RTC);
  63        ixp2000_reg_write(IXP2000_SLOWPORT_PCR, new_cfg->PCR);
  64        ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, new_cfg->ADC);
  65}
  66
  67void ixp2000_release_slowport(struct slowport_cfg *old_cfg)
  68{
  69        ixp2000_reg_write(IXP2000_SLOWPORT_CCR, old_cfg->CCR);
  70        ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, old_cfg->WTC);
  71        ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, old_cfg->RTC);
  72        ixp2000_reg_write(IXP2000_SLOWPORT_PCR, old_cfg->PCR);
  73        ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, old_cfg->ADC);
  74
  75        spin_unlock_irqrestore(&ixp2000_slowport_lock, 
  76                                        ixp2000_slowport_irq_flags);
  77}
  78
  79/*************************************************************************
  80 * Chip specific mappings shared by all IXP2000 systems
  81 *************************************************************************/
  82static struct map_desc ixp2000_io_desc[] __initdata = {
  83        {
  84                .virtual        = IXP2000_CAP_VIRT_BASE,
  85                .pfn            = __phys_to_pfn(IXP2000_CAP_PHYS_BASE),
  86                .length         = IXP2000_CAP_SIZE,
  87                .type           = MT_DEVICE_IXP2000,
  88        }, {
  89                .virtual        = IXP2000_INTCTL_VIRT_BASE,
  90                .pfn            = __phys_to_pfn(IXP2000_INTCTL_PHYS_BASE),
  91                .length         = IXP2000_INTCTL_SIZE,
  92                .type           = MT_DEVICE_IXP2000,
  93        }, {
  94                .virtual        = IXP2000_PCI_CREG_VIRT_BASE,
  95                .pfn            = __phys_to_pfn(IXP2000_PCI_CREG_PHYS_BASE),
  96                .length         = IXP2000_PCI_CREG_SIZE,
  97                .type           = MT_DEVICE_IXP2000,
  98        }, {
  99                .virtual        = IXP2000_PCI_CSR_VIRT_BASE,
 100                .pfn            = __phys_to_pfn(IXP2000_PCI_CSR_PHYS_BASE),
 101                .length         = IXP2000_PCI_CSR_SIZE,
 102                .type           = MT_DEVICE_IXP2000,
 103        }, {
 104                .virtual        = IXP2000_MSF_VIRT_BASE,
 105                .pfn            = __phys_to_pfn(IXP2000_MSF_PHYS_BASE),
 106                .length         = IXP2000_MSF_SIZE,
 107                .type           = MT_DEVICE_IXP2000,
 108        }, {
 109                .virtual        = IXP2000_SCRATCH_RING_VIRT_BASE,
 110                .pfn            = __phys_to_pfn(IXP2000_SCRATCH_RING_PHYS_BASE),
 111                .length         = IXP2000_SCRATCH_RING_SIZE,
 112                .type           = MT_DEVICE_IXP2000,
 113        }, {
 114                .virtual        = IXP2000_SRAM0_VIRT_BASE,
 115                .pfn            = __phys_to_pfn(IXP2000_SRAM0_PHYS_BASE),
 116                .length         = IXP2000_SRAM0_SIZE,
 117                .type           = MT_DEVICE_IXP2000,
 118        }, {
 119                .virtual        = IXP2000_PCI_IO_VIRT_BASE,
 120                .pfn            = __phys_to_pfn(IXP2000_PCI_IO_PHYS_BASE),
 121                .length         = IXP2000_PCI_IO_SIZE,
 122                .type           = MT_DEVICE_IXP2000,
 123        }, {
 124                .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
 125                .pfn            = __phys_to_pfn(IXP2000_PCI_CFG0_PHYS_BASE),
 126                .length         = IXP2000_PCI_CFG0_SIZE,
 127                .type           = MT_DEVICE_IXP2000,
 128        }, {
 129                .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
 130                .pfn            = __phys_to_pfn(IXP2000_PCI_CFG1_PHYS_BASE),
 131                .length         = IXP2000_PCI_CFG1_SIZE,
 132                .type           = MT_DEVICE_IXP2000,
 133        }
 134};
 135
 136void __init ixp2000_map_io(void)
 137{
 138        /*
 139         * On IXP2400 CPUs we need to use MT_DEVICE_IXP2000 so that
 140         * XCB=101 (to avoid triggering erratum #66), and given that
 141         * this mode speeds up I/O accesses and we have write buffer
 142         * flushes in the right places anyway, it doesn't hurt to use
 143         * XCB=101 for all IXP2000s.
 144         */
 145        iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
 146
 147        /* Set slowport to 8-bit mode.  */
 148        ixp2000_reg_wrb(IXP2000_SLOWPORT_FRM, 1);
 149}
 150
 151
 152/*************************************************************************
 153 * Serial port support for IXP2000
 154 *************************************************************************/
 155static struct plat_serial8250_port ixp2000_serial_port[] = {
 156        {
 157                .mapbase        = IXP2000_UART_PHYS_BASE,
 158                .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
 159                .irq            = IRQ_IXP2000_UART,
 160                .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 161                .iotype         = UPIO_MEM,
 162                .regshift       = 2,
 163                .uartclk        = 50000000,
 164        },
 165        { },
 166};
 167
 168static struct resource ixp2000_uart_resource = {
 169        .start          = IXP2000_UART_PHYS_BASE,
 170        .end            = IXP2000_UART_PHYS_BASE + 0x1f,
 171        .flags          = IORESOURCE_MEM,
 172};
 173
 174static struct platform_device ixp2000_serial_device = {
 175        .name           = "serial8250",
 176        .id             = PLAT8250_DEV_PLATFORM,
 177        .dev            = {
 178                .platform_data          = ixp2000_serial_port,
 179        },
 180        .num_resources  = 1,
 181        .resource       = &ixp2000_uart_resource,
 182};
 183
 184void __init ixp2000_uart_init(void)
 185{
 186        platform_device_register(&ixp2000_serial_device);
 187}
 188
 189
 190/*************************************************************************
 191 * Timer-tick functions for IXP2000
 192 *************************************************************************/
 193static unsigned ticks_per_jiffy;
 194static unsigned ticks_per_usec;
 195static unsigned next_jiffy_time;
 196static volatile unsigned long *missing_jiffy_timer_csr;
 197
 198unsigned long ixp2000_gettimeoffset (void)
 199{
 200        unsigned long offset;
 201
 202        offset = next_jiffy_time - *missing_jiffy_timer_csr;
 203
 204        return offset / ticks_per_usec;
 205}
 206
 207static int ixp2000_timer_interrupt(int irq, void *dev_id)
 208{
 209        /* clear timer 1 */
 210        ixp2000_reg_wrb(IXP2000_T1_CLR, 1);
 211
 212        while ((signed long)(next_jiffy_time - *missing_jiffy_timer_csr)
 213                                                        >= ticks_per_jiffy) {
 214                timer_tick();
 215                next_jiffy_time -= ticks_per_jiffy;
 216        }
 217
 218        return IRQ_HANDLED;
 219}
 220
 221static struct irqaction ixp2000_timer_irq = {
 222        .name           = "IXP2000 Timer Tick",
 223        .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 224        .handler        = ixp2000_timer_interrupt,
 225};
 226
 227void __init ixp2000_init_time(unsigned long tick_rate)
 228{
 229        ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
 230        ticks_per_usec = tick_rate / 1000000;
 231
 232        /*
 233         * We use timer 1 as our timer interrupt.
 234         */
 235        ixp2000_reg_write(IXP2000_T1_CLR, 0);
 236        ixp2000_reg_write(IXP2000_T1_CLD, ticks_per_jiffy - 1);
 237        ixp2000_reg_write(IXP2000_T1_CTL, (1 << 7));
 238
 239        /*
 240         * We use a second timer as a monotonic counter for tracking
 241         * missed jiffies.  The IXP2000 has four timers, but if we're
 242         * on an A-step IXP2800, timer 2 and 3 don't work, so on those
 243         * chips we use timer 4.  Timer 4 is the only timer that can
 244         * be used for the watchdog, so we use timer 2 if we're on a
 245         * non-buggy chip.
 246         */
 247        if ((*IXP2000_PRODUCT_ID & 0x001ffef0) == 0x00000000) {
 248                printk(KERN_INFO "Enabling IXP2800 erratum #25 workaround\n");
 249
 250                ixp2000_reg_write(IXP2000_T4_CLR, 0);
 251                ixp2000_reg_write(IXP2000_T4_CLD, -1);
 252                ixp2000_reg_wrb(IXP2000_T4_CTL, (1 << 7));
 253                missing_jiffy_timer_csr = IXP2000_T4_CSR;
 254        } else {
 255                ixp2000_reg_write(IXP2000_T2_CLR, 0);
 256                ixp2000_reg_write(IXP2000_T2_CLD, -1);
 257                ixp2000_reg_wrb(IXP2000_T2_CTL, (1 << 7));
 258                missing_jiffy_timer_csr = IXP2000_T2_CSR;
 259        }
 260        next_jiffy_time = 0xffffffff;
 261
 262        /* register for interrupt */
 263        setup_irq(IRQ_IXP2000_TIMER1, &ixp2000_timer_irq);
 264}
 265
 266/*************************************************************************
 267 * GPIO helpers
 268 *************************************************************************/
 269static unsigned long GPIO_IRQ_falling_edge;
 270static unsigned long GPIO_IRQ_rising_edge;
 271static unsigned long GPIO_IRQ_level_low;
 272static unsigned long GPIO_IRQ_level_high;
 273
 274static void update_gpio_int_csrs(void)
 275{
 276        ixp2000_reg_write(IXP2000_GPIO_FEDR, GPIO_IRQ_falling_edge);
 277        ixp2000_reg_write(IXP2000_GPIO_REDR, GPIO_IRQ_rising_edge);
 278        ixp2000_reg_write(IXP2000_GPIO_LSLR, GPIO_IRQ_level_low);
 279        ixp2000_reg_wrb(IXP2000_GPIO_LSHR, GPIO_IRQ_level_high);
 280}
 281
 282void gpio_line_config(int line, int direction)
 283{
 284        unsigned long flags;
 285
 286        local_irq_save(flags);
 287        if (direction == GPIO_OUT) {
 288                /* if it's an output, it ain't an interrupt anymore */
 289                GPIO_IRQ_falling_edge &= ~(1 << line);
 290                GPIO_IRQ_rising_edge &= ~(1 << line);
 291                GPIO_IRQ_level_low &= ~(1 << line);
 292                GPIO_IRQ_level_high &= ~(1 << line);
 293                update_gpio_int_csrs();
 294
 295                ixp2000_reg_wrb(IXP2000_GPIO_PDSR, 1 << line);
 296        } else if (direction == GPIO_IN) {
 297                ixp2000_reg_wrb(IXP2000_GPIO_PDCR, 1 << line);
 298        }
 299        local_irq_restore(flags);
 300}
 301EXPORT_SYMBOL(gpio_line_config);
 302
 303
 304/*************************************************************************
 305 * IRQ handling IXP2000
 306 *************************************************************************/
 307static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irq_desc *desc)
 308{                               
 309        int i;
 310        unsigned long status = *IXP2000_GPIO_INST;
 311                   
 312        for (i = 0; i <= 7; i++) {
 313                if (status & (1<<i)) {
 314                        desc = irq_desc + i + IRQ_IXP2000_GPIO0;
 315                        desc_handle_irq(i + IRQ_IXP2000_GPIO0, desc);
 316                }
 317        }
 318}
 319
 320static int ixp2000_GPIO_irq_type(unsigned int irq, unsigned int type)
 321{
 322        int line = irq - IRQ_IXP2000_GPIO0;
 323
 324        /*
 325         * First, configure this GPIO line as an input.
 326         */
 327        ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
 328
 329        /*
 330         * Then, set the proper trigger type.
 331         */
 332        if (type & IRQ_TYPE_EDGE_FALLING)
 333                GPIO_IRQ_falling_edge |= 1 << line;
 334        else
 335                GPIO_IRQ_falling_edge &= ~(1 << line);
 336        if (type & IRQ_TYPE_EDGE_RISING)
 337                GPIO_IRQ_rising_edge |= 1 << line;
 338        else
 339                GPIO_IRQ_rising_edge &= ~(1 << line);
 340        if (type & IRQ_TYPE_LEVEL_LOW)
 341                GPIO_IRQ_level_low |= 1 << line;
 342        else
 343                GPIO_IRQ_level_low &= ~(1 << line);
 344        if (type & IRQ_TYPE_LEVEL_HIGH)
 345                GPIO_IRQ_level_high |= 1 << line;
 346        else
 347                GPIO_IRQ_level_high &= ~(1 << line);
 348        update_gpio_int_csrs();
 349
 350        return 0;
 351}
 352
 353static void ixp2000_GPIO_irq_mask_ack(unsigned int irq)
 354{
 355        ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 356
 357        ixp2000_reg_write(IXP2000_GPIO_EDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 358        ixp2000_reg_write(IXP2000_GPIO_LDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 359        ixp2000_reg_wrb(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
 360}
 361
 362static void ixp2000_GPIO_irq_mask(unsigned int irq)
 363{
 364        ixp2000_reg_wrb(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 365}
 366
 367static void ixp2000_GPIO_irq_unmask(unsigned int irq)
 368{
 369        ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 370}
 371
 372static struct irq_chip ixp2000_GPIO_irq_chip = {
 373        .ack            = ixp2000_GPIO_irq_mask_ack,
 374        .mask           = ixp2000_GPIO_irq_mask,
 375        .unmask         = ixp2000_GPIO_irq_unmask,
 376        .set_type       = ixp2000_GPIO_irq_type,
 377};
 378
 379static void ixp2000_pci_irq_mask(unsigned int irq)
 380{
 381        unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 382        if (irq == IRQ_IXP2000_PCIA)
 383                ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
 384        else if (irq == IRQ_IXP2000_PCIB)
 385                ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 27)));
 386}
 387
 388static void ixp2000_pci_irq_unmask(unsigned int irq)
 389{
 390        unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 391        if (irq == IRQ_IXP2000_PCIA)
 392                ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
 393        else if (irq == IRQ_IXP2000_PCIB)
 394                ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 27)));
 395}
 396
 397/*
 398 * Error interrupts. These are used extensively by the microengine drivers
 399 */
 400static void ixp2000_err_irq_handler(unsigned int irq, struct irq_desc *desc)
 401{
 402        int i;
 403        unsigned long status = *IXP2000_IRQ_ERR_STATUS;
 404
 405        for(i = 31; i >= 0; i--) {
 406                if(status & (1 << i)) {
 407                        desc = irq_desc + IRQ_IXP2000_DRAM0_MIN_ERR + i;
 408                        desc_handle_irq(IRQ_IXP2000_DRAM0_MIN_ERR + i, desc);
 409                }
 410        }
 411}
 412
 413static void ixp2000_err_irq_mask(unsigned int irq)
 414{
 415        ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_CLR,
 416                        (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
 417}
 418
 419static void ixp2000_err_irq_unmask(unsigned int irq)
 420{
 421        ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_SET,
 422                        (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
 423}
 424
 425static struct irq_chip ixp2000_err_irq_chip = {
 426        .ack    = ixp2000_err_irq_mask,
 427        .mask   = ixp2000_err_irq_mask,
 428        .unmask = ixp2000_err_irq_unmask
 429};
 430
 431static struct irq_chip ixp2000_pci_irq_chip = {
 432        .ack    = ixp2000_pci_irq_mask,
 433        .mask   = ixp2000_pci_irq_mask,
 434        .unmask = ixp2000_pci_irq_unmask
 435};
 436
 437static void ixp2000_irq_mask(unsigned int irq)
 438{
 439        ixp2000_reg_wrb(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
 440}
 441
 442static void ixp2000_irq_unmask(unsigned int irq)
 443{
 444        ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << irq));
 445}
 446
 447static struct irq_chip ixp2000_irq_chip = {
 448        .ack    = ixp2000_irq_mask,
 449        .mask   = ixp2000_irq_mask,
 450        .unmask = ixp2000_irq_unmask
 451};
 452
 453void __init ixp2000_init_irq(void)
 454{
 455        int irq;
 456
 457        /*
 458         * Mask all sources
 459         */
 460        ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
 461        ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
 462
 463        /* clear all GPIO edge/level detects */
 464        ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
 465        ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
 466        ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
 467        ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
 468        ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
 469
 470        /* clear PCI interrupt sources */
 471        ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
 472
 473        /*
 474         * Certain bits in the IRQ status register of the 
 475         * IXP2000 are reserved. Instead of trying to map
 476         * things non 1:1 from bit position to IRQ number,
 477         * we mark the reserved IRQs as invalid. This makes
 478         * our mask/unmask code much simpler.
 479         */
 480        for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
 481                if ((1 << irq) & IXP2000_VALID_IRQ_MASK) {
 482                        set_irq_chip(irq, &ixp2000_irq_chip);
 483                        set_irq_handler(irq, handle_level_irq);
 484                        set_irq_flags(irq, IRQF_VALID);
 485                } else set_irq_flags(irq, 0);
 486        }
 487
 488        for (irq = IRQ_IXP2000_DRAM0_MIN_ERR; irq <= IRQ_IXP2000_SP_INT; irq++) {
 489                if((1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)) &
 490                                IXP2000_VALID_ERR_IRQ_MASK) {
 491                        set_irq_chip(irq, &ixp2000_err_irq_chip);
 492                        set_irq_handler(irq, handle_level_irq);
 493                        set_irq_flags(irq, IRQF_VALID);
 494                }
 495                else
 496                        set_irq_flags(irq, 0);
 497        }
 498        set_irq_chained_handler(IRQ_IXP2000_ERRSUM, ixp2000_err_irq_handler);
 499
 500        for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
 501                set_irq_chip(irq, &ixp2000_GPIO_irq_chip);
 502                set_irq_handler(irq, handle_level_irq);
 503                set_irq_flags(irq, IRQF_VALID);
 504        }
 505        set_irq_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
 506
 507        /*
 508         * Enable PCI irqs.  The actual PCI[AB] decoding is done in
 509         * entry-macro.S, so we don't need a chained handler for the
 510         * PCI interrupt source.
 511         */
 512        ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
 513        for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
 514                set_irq_chip(irq, &ixp2000_pci_irq_chip);
 515                set_irq_handler(irq, handle_level_irq);
 516                set_irq_flags(irq, IRQF_VALID);
 517        }
 518}
 519
 520