linux/arch/arm/mach-ixp23xx/core.c
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   1/*
   2 * arch/arm/mach-ixp23xx/core.c
   3 *
   4 * Core routines for IXP23xx chips
   5 *
   6 * Author: Deepak Saxena <dsaxena@plexity.net>
   7 *
   8 * Copyright 2005 (c) MontaVista Software, Inc.
   9 *
  10 * Based on 2.4 code Copyright 2004 (c) 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/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
  32#include <asm/types.h>
  33#include <asm/setup.h>
  34#include <asm/memory.h>
  35#include <mach/hardware.h>
  36#include <asm/irq.h>
  37#include <asm/system.h>
  38#include <asm/tlbflush.h>
  39#include <asm/pgtable.h>
  40
  41#include <asm/mach/map.h>
  42#include <asm/mach/time.h>
  43#include <asm/mach/irq.h>
  44#include <asm/mach/arch.h>
  45
  46
  47/*************************************************************************
  48 * Chip specific mappings shared by all IXP23xx systems
  49 *************************************************************************/
  50static struct map_desc ixp23xx_io_desc[] __initdata = {
  51        { /* XSI-CPP CSRs */
  52                .virtual        = IXP23XX_XSI2CPP_CSR_VIRT,
  53                .pfn            = __phys_to_pfn(IXP23XX_XSI2CPP_CSR_PHYS),
  54                .length         = IXP23XX_XSI2CPP_CSR_SIZE,
  55                .type           = MT_DEVICE,
  56        }, { /* Expansion Bus Config */
  57                .virtual        = IXP23XX_EXP_CFG_VIRT,
  58                .pfn            = __phys_to_pfn(IXP23XX_EXP_CFG_PHYS),
  59                .length         = IXP23XX_EXP_CFG_SIZE,
  60                .type           = MT_DEVICE,
  61        }, { /* UART, Interrupt ctrl, GPIO, timers, NPEs, MACS,.... */
  62                .virtual        = IXP23XX_PERIPHERAL_VIRT,
  63                .pfn            = __phys_to_pfn(IXP23XX_PERIPHERAL_PHYS),
  64                .length         = IXP23XX_PERIPHERAL_SIZE,
  65                .type           = MT_DEVICE,
  66        }, { /* CAP CSRs */
  67                .virtual        = IXP23XX_CAP_CSR_VIRT,
  68                .pfn            = __phys_to_pfn(IXP23XX_CAP_CSR_PHYS),
  69                .length         = IXP23XX_CAP_CSR_SIZE,
  70                .type           = MT_DEVICE,
  71        }, { /* MSF CSRs */
  72                .virtual        = IXP23XX_MSF_CSR_VIRT,
  73                .pfn            = __phys_to_pfn(IXP23XX_MSF_CSR_PHYS),
  74                .length         = IXP23XX_MSF_CSR_SIZE,
  75                .type           = MT_DEVICE,
  76        }, { /* PCI I/O Space */
  77                .virtual        = IXP23XX_PCI_IO_VIRT,
  78                .pfn            = __phys_to_pfn(IXP23XX_PCI_IO_PHYS),
  79                .length         = IXP23XX_PCI_IO_SIZE,
  80                .type           = MT_DEVICE,
  81        }, { /* PCI Config Space */
  82                .virtual        = IXP23XX_PCI_CFG_VIRT,
  83                .pfn            = __phys_to_pfn(IXP23XX_PCI_CFG_PHYS),
  84                .length         = IXP23XX_PCI_CFG_SIZE,
  85                .type           = MT_DEVICE,
  86        }, { /* PCI local CFG CSRs */
  87                .virtual        = IXP23XX_PCI_CREG_VIRT,
  88                .pfn            = __phys_to_pfn(IXP23XX_PCI_CREG_PHYS),
  89                .length         = IXP23XX_PCI_CREG_SIZE,
  90                .type           = MT_DEVICE,
  91        }, { /* PCI MEM Space */
  92                .virtual        = IXP23XX_PCI_MEM_VIRT,
  93                .pfn            = __phys_to_pfn(IXP23XX_PCI_MEM_PHYS),
  94                .length         = IXP23XX_PCI_MEM_SIZE,
  95                .type           = MT_DEVICE,
  96        }
  97};
  98
  99void __init ixp23xx_map_io(void)
 100{
 101        iotable_init(ixp23xx_io_desc, ARRAY_SIZE(ixp23xx_io_desc));
 102}
 103
 104
 105/***************************************************************************
 106 * IXP23xx Interrupt Handling
 107 ***************************************************************************/
 108enum ixp23xx_irq_type {
 109        IXP23XX_IRQ_LEVEL, IXP23XX_IRQ_EDGE
 110};
 111
 112static void ixp23xx_config_irq(unsigned int, enum ixp23xx_irq_type);
 113
 114static int ixp23xx_irq_set_type(unsigned int irq, unsigned int type)
 115{
 116        int line = irq - IRQ_IXP23XX_GPIO6 + 6;
 117        u32 int_style;
 118        enum ixp23xx_irq_type irq_type;
 119        volatile u32 *int_reg;
 120
 121        /*
 122         * Only GPIOs 6-15 are wired to interrupts on IXP23xx
 123         */
 124        if (line < 6 || line > 15)
 125                return -EINVAL;
 126
 127        switch (type) {
 128        case IRQ_TYPE_EDGE_BOTH:
 129                int_style = IXP23XX_GPIO_STYLE_TRANSITIONAL;
 130                irq_type = IXP23XX_IRQ_EDGE;
 131                break;
 132        case IRQ_TYPE_EDGE_RISING:
 133                int_style = IXP23XX_GPIO_STYLE_RISING_EDGE;
 134                irq_type = IXP23XX_IRQ_EDGE;
 135                break;
 136        case IRQ_TYPE_EDGE_FALLING:
 137                int_style = IXP23XX_GPIO_STYLE_FALLING_EDGE;
 138                irq_type = IXP23XX_IRQ_EDGE;
 139                break;
 140        case IRQ_TYPE_LEVEL_HIGH:
 141                int_style = IXP23XX_GPIO_STYLE_ACTIVE_HIGH;
 142                irq_type = IXP23XX_IRQ_LEVEL;
 143                break;
 144        case IRQ_TYPE_LEVEL_LOW:
 145                int_style = IXP23XX_GPIO_STYLE_ACTIVE_LOW;
 146                irq_type = IXP23XX_IRQ_LEVEL;
 147                break;
 148        default:
 149                return -EINVAL;
 150        }
 151
 152        ixp23xx_config_irq(irq, irq_type);
 153
 154        if (line >= 8) {        /* pins 8-15 */
 155                line -= 8;
 156                int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT2R;
 157        } else {                /* pins 0-7 */
 158                int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT1R;
 159        }
 160
 161        /*
 162         * Clear pending interrupts
 163         */
 164        *IXP23XX_GPIO_GPISR = (1 << line);
 165
 166        /* Clear the style for the appropriate pin */
 167        *int_reg &= ~(IXP23XX_GPIO_STYLE_MASK <<
 168                        (line * IXP23XX_GPIO_STYLE_SIZE));
 169
 170        /* Set the new style */
 171        *int_reg |= (int_style << (line * IXP23XX_GPIO_STYLE_SIZE));
 172
 173        return 0;
 174}
 175
 176static void ixp23xx_irq_mask(unsigned int irq)
 177{
 178        volatile unsigned long *intr_reg;
 179
 180        if (irq >= 56)
 181                irq += 8;
 182
 183        intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 184        *intr_reg &= ~(1 << (irq % 32));
 185}
 186
 187static void ixp23xx_irq_ack(unsigned int irq)
 188{
 189        int line = irq - IRQ_IXP23XX_GPIO6 + 6;
 190
 191        if ((line < 6) || (line > 15))
 192                return;
 193
 194        *IXP23XX_GPIO_GPISR = (1 << line);
 195}
 196
 197/*
 198 * Level triggered interrupts on GPIO lines can only be cleared when the
 199 * interrupt condition disappears.
 200 */
 201static void ixp23xx_irq_level_unmask(unsigned int irq)
 202{
 203        volatile unsigned long *intr_reg;
 204
 205        ixp23xx_irq_ack(irq);
 206
 207        if (irq >= 56)
 208                irq += 8;
 209
 210        intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 211        *intr_reg |= (1 << (irq % 32));
 212}
 213
 214static void ixp23xx_irq_edge_unmask(unsigned int irq)
 215{
 216        volatile unsigned long *intr_reg;
 217
 218        if (irq >= 56)
 219                irq += 8;
 220
 221        intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 222        *intr_reg |= (1 << (irq % 32));
 223}
 224
 225static struct irq_chip ixp23xx_irq_level_chip = {
 226        .ack            = ixp23xx_irq_mask,
 227        .mask           = ixp23xx_irq_mask,
 228        .unmask         = ixp23xx_irq_level_unmask,
 229        .set_type       = ixp23xx_irq_set_type
 230};
 231
 232static struct irq_chip ixp23xx_irq_edge_chip = {
 233        .ack            = ixp23xx_irq_ack,
 234        .mask           = ixp23xx_irq_mask,
 235        .unmask         = ixp23xx_irq_edge_unmask,
 236        .set_type       = ixp23xx_irq_set_type
 237};
 238
 239static void ixp23xx_pci_irq_mask(unsigned int irq)
 240{
 241        *IXP23XX_PCI_XSCALE_INT_ENABLE &= ~(1 << (IRQ_IXP23XX_INTA + 27 - irq));
 242}
 243
 244static void ixp23xx_pci_irq_unmask(unsigned int irq)
 245{
 246        *IXP23XX_PCI_XSCALE_INT_ENABLE |= (1 << (IRQ_IXP23XX_INTA + 27 - irq));
 247}
 248
 249/*
 250 * TODO: Should this just be done at ASM level?
 251 */
 252static void pci_handler(unsigned int irq, struct irq_desc *desc)
 253{
 254        u32 pci_interrupt;
 255        unsigned int irqno;
 256
 257        pci_interrupt = *IXP23XX_PCI_XSCALE_INT_STATUS;
 258
 259        desc->chip->ack(irq);
 260
 261        /* See which PCI_INTA, or PCI_INTB interrupted */
 262        if (pci_interrupt & (1 << 26)) {
 263                irqno = IRQ_IXP23XX_INTB;
 264        } else if (pci_interrupt & (1 << 27)) {
 265                irqno = IRQ_IXP23XX_INTA;
 266        } else {
 267                BUG();
 268        }
 269
 270        generic_handle_irq(irqno);
 271
 272        desc->chip->unmask(irq);
 273}
 274
 275static struct irq_chip ixp23xx_pci_irq_chip = {
 276        .ack    = ixp23xx_pci_irq_mask,
 277        .mask   = ixp23xx_pci_irq_mask,
 278        .unmask = ixp23xx_pci_irq_unmask
 279};
 280
 281static void ixp23xx_config_irq(unsigned int irq, enum ixp23xx_irq_type type)
 282{
 283        switch (type) {
 284        case IXP23XX_IRQ_LEVEL:
 285                set_irq_chip(irq, &ixp23xx_irq_level_chip);
 286                set_irq_handler(irq, handle_level_irq);
 287                break;
 288        case IXP23XX_IRQ_EDGE:
 289                set_irq_chip(irq, &ixp23xx_irq_edge_chip);
 290                set_irq_handler(irq, handle_edge_irq);
 291                break;
 292        }
 293        set_irq_flags(irq, IRQF_VALID);
 294}
 295
 296void __init ixp23xx_init_irq(void)
 297{
 298        int irq;
 299
 300        /* Route everything to IRQ */
 301        *IXP23XX_INTR_SEL1 = 0x0;
 302        *IXP23XX_INTR_SEL2 = 0x0;
 303        *IXP23XX_INTR_SEL3 = 0x0;
 304        *IXP23XX_INTR_SEL4 = 0x0;
 305
 306        /* Mask all sources */
 307        *IXP23XX_INTR_EN1 = 0x0;
 308        *IXP23XX_INTR_EN2 = 0x0;
 309        *IXP23XX_INTR_EN3 = 0x0;
 310        *IXP23XX_INTR_EN4 = 0x0;
 311
 312        /*
 313         * Configure all IRQs for level-sensitive operation
 314         */
 315        for (irq = 0; irq <= NUM_IXP23XX_RAW_IRQS; irq++) {
 316                ixp23xx_config_irq(irq, IXP23XX_IRQ_LEVEL);
 317        }
 318
 319        for (irq = IRQ_IXP23XX_INTA; irq <= IRQ_IXP23XX_INTB; irq++) {
 320                set_irq_chip(irq, &ixp23xx_pci_irq_chip);
 321                set_irq_handler(irq, handle_level_irq);
 322                set_irq_flags(irq, IRQF_VALID);
 323        }
 324
 325        set_irq_chained_handler(IRQ_IXP23XX_PCI_INT_RPH, pci_handler);
 326}
 327
 328
 329/*************************************************************************
 330 * Timer-tick functions for IXP23xx
 331 *************************************************************************/
 332#define CLOCK_TICKS_PER_USEC    (CLOCK_TICK_RATE / USEC_PER_SEC)
 333
 334static unsigned long next_jiffy_time;
 335
 336static unsigned long
 337ixp23xx_gettimeoffset(void)
 338{
 339        unsigned long elapsed;
 340
 341        elapsed = *IXP23XX_TIMER_CONT - (next_jiffy_time - LATCH);
 342
 343        return elapsed / CLOCK_TICKS_PER_USEC;
 344}
 345
 346static irqreturn_t
 347ixp23xx_timer_interrupt(int irq, void *dev_id)
 348{
 349        /* Clear Pending Interrupt by writing '1' to it */
 350        *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
 351        while ((signed long)(*IXP23XX_TIMER_CONT - next_jiffy_time) >= LATCH) {
 352                timer_tick();
 353                next_jiffy_time += LATCH;
 354        }
 355
 356        return IRQ_HANDLED;
 357}
 358
 359static struct irqaction ixp23xx_timer_irq = {
 360        .name           = "IXP23xx Timer Tick",
 361        .handler        = ixp23xx_timer_interrupt,
 362        .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 363};
 364
 365void __init ixp23xx_init_timer(void)
 366{
 367        /* Clear Pending Interrupt by writing '1' to it */
 368        *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
 369
 370        /* Setup the Timer counter value */
 371        *IXP23XX_TIMER1_RELOAD =
 372                (LATCH & ~IXP23XX_TIMER_RELOAD_MASK) | IXP23XX_TIMER_ENABLE;
 373
 374        *IXP23XX_TIMER_CONT = 0;
 375        next_jiffy_time = LATCH;
 376
 377        /* Connect the interrupt handler and enable the interrupt */
 378        setup_irq(IRQ_IXP23XX_TIMER1, &ixp23xx_timer_irq);
 379}
 380
 381struct sys_timer ixp23xx_timer = {
 382        .init           = ixp23xx_init_timer,
 383        .offset         = ixp23xx_gettimeoffset,
 384};
 385
 386
 387/*************************************************************************
 388 * IXP23xx Platform Initialization
 389 *************************************************************************/
 390static struct resource ixp23xx_uart_resources[] = {
 391        {
 392                .start          = IXP23XX_UART1_PHYS,
 393                .end            = IXP23XX_UART1_PHYS + 0x0fff,
 394                .flags          = IORESOURCE_MEM
 395        }, {
 396                .start          = IXP23XX_UART2_PHYS,
 397                .end            = IXP23XX_UART2_PHYS + 0x0fff,
 398                .flags          = IORESOURCE_MEM
 399        }
 400};
 401
 402static struct plat_serial8250_port ixp23xx_uart_data[] = {
 403        {
 404                .mapbase        = IXP23XX_UART1_PHYS,
 405                .membase        = (char *)(IXP23XX_UART1_VIRT + 3),
 406                .irq            = IRQ_IXP23XX_UART1,
 407                .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 408                .iotype         = UPIO_MEM,
 409                .regshift       = 2,
 410                .uartclk        = IXP23XX_UART_XTAL,
 411        }, {
 412                .mapbase        = IXP23XX_UART2_PHYS,
 413                .membase        = (char *)(IXP23XX_UART2_VIRT + 3),
 414                .irq            = IRQ_IXP23XX_UART2,
 415                .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 416                .iotype         = UPIO_MEM,
 417                .regshift       = 2,
 418                .uartclk        = IXP23XX_UART_XTAL,
 419        },
 420        { },
 421};
 422
 423static struct platform_device ixp23xx_uart = {
 424        .name                   = "serial8250",
 425        .id                     = 0,
 426        .dev.platform_data      = ixp23xx_uart_data,
 427        .num_resources          = 2,
 428        .resource               = ixp23xx_uart_resources,
 429};
 430
 431static struct platform_device *ixp23xx_devices[] __initdata = {
 432        &ixp23xx_uart,
 433};
 434
 435void __init ixp23xx_sys_init(void)
 436{
 437        *IXP23XX_EXP_UNIT_FUSE |= 0xf;
 438        platform_add_devices(ixp23xx_devices, ARRAY_SIZE(ixp23xx_devices));
 439}
 440