arch/arm/mach-ixp23xx/core.c

   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  *************************************************************************/
  50 static 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
  99 void __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  ***************************************************************************/
 108 enum ixp23xx_irq_type {
 109         IXP23XX_IRQ_LEVEL, IXP23XX_IRQ_EDGE
 110 };
 111
 112 static void ixp23xx_config_irq(unsigned int, enum ixp23xx_irq_type);
 113
 114 static int ixp23xx_irq_set_type(struct irq_data *d, unsigned int type)
 115 {
 116         int line = d->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(d->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
 176 static void ixp23xx_irq_mask(struct irq_data *d)
 177 {
 178         volatile unsigned long *intr_reg;
 179         unsigned int irq = d->irq;
 180
 181         if (irq >= 56)
 182                 irq += 8;
 183
 184         intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 185         *intr_reg &= ~(1 << (irq % 32));
 186 }
 187
 188 static void ixp23xx_irq_ack(struct irq_data *d)
 189 {
 190         int line = d->irq - IRQ_IXP23XX_GPIO6 + 6;
 191
 192         if ((line < 6) || (line > 15))
 193                 return;
 194
 195         *IXP23XX_GPIO_GPISR = (1 << line);
 196 }
 197
 198 /*
 199  * Level triggered interrupts on GPIO lines can only be cleared when the
 200  * interrupt condition disappears.
 201  */
 202 static void ixp23xx_irq_level_unmask(struct irq_data *d)
 203 {
 204         volatile unsigned long *intr_reg;
 205         unsigned int irq = d->irq;
 206
 207         ixp23xx_irq_ack(d);
 208
 209         if (irq >= 56)
 210                 irq += 8;
 211
 212         intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 213         *intr_reg |= (1 << (irq % 32));
 214 }
 215
 216 static void ixp23xx_irq_edge_unmask(struct irq_data *d)
 217 {
 218         volatile unsigned long *intr_reg;
 219         unsigned int irq = d->irq;
 220
 221         if (irq >= 56)
 222                 irq += 8;
 223
 224         intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
 225         *intr_reg |= (1 << (irq % 32));
 226 }
 227
 228 static struct irq_chip ixp23xx_irq_level_chip = {
 229         .irq_ack        = ixp23xx_irq_mask,
 230         .irq_mask       = ixp23xx_irq_mask,
 231         .irq_unmask     = ixp23xx_irq_level_unmask,
 232         .irq_set_type   = ixp23xx_irq_set_type
 233 };
 234
 235 static struct irq_chip ixp23xx_irq_edge_chip = {
 236         .irq_ack        = ixp23xx_irq_ack,
 237         .irq_mask       = ixp23xx_irq_mask,
 238         .irq_unmask     = ixp23xx_irq_edge_unmask,
 239         .irq_set_type   = ixp23xx_irq_set_type
 240 };
 241
 242 static void ixp23xx_pci_irq_mask(struct irq_data *d)
 243 {
 244         unsigned int irq = d->irq;
 245
 246         *IXP23XX_PCI_XSCALE_INT_ENABLE &= ~(1 << (IRQ_IXP23XX_INTA + 27 - irq));
 247 }
 248
 249 static void ixp23xx_pci_irq_unmask(struct irq_data *d)
 250 {
 251         unsigned int irq = d->irq;
 252
 253         *IXP23XX_PCI_XSCALE_INT_ENABLE |= (1 << (IRQ_IXP23XX_INTA + 27 - irq));
 254 }
 255
 256 /*
 257  * TODO: Should this just be done at ASM level?
 258  */
 259 static void pci_handler(unsigned int irq, struct irq_desc *desc)
 260 {
 261         u32 pci_interrupt;
 262         unsigned int irqno;
 263
 264         pci_interrupt = *IXP23XX_PCI_XSCALE_INT_STATUS;
 265
 266         desc->irq_data.chip->irq_ack(&desc->irq_data);
 267
 268         /* See which PCI_INTA, or PCI_INTB interrupted */
 269         if (pci_interrupt & (1 << 26)) {
 270                 irqno = IRQ_IXP23XX_INTB;
 271         } else if (pci_interrupt & (1 << 27)) {
 272                 irqno = IRQ_IXP23XX_INTA;
 273         } else {
 274                 BUG();
 275         }
 276
 277         generic_handle_irq(irqno);
 278
 279         desc->irq_data.chip->irq_unmask(&desc->irq_data);
 280 }
 281
 282 static struct irq_chip ixp23xx_pci_irq_chip = {
 283         .irq_ack        = ixp23xx_pci_irq_mask,
 284         .irq_mask       = ixp23xx_pci_irq_mask,
 285         .irq_unmask     = ixp23xx_pci_irq_unmask
 286 };
 287
 288 static void ixp23xx_config_irq(unsigned int irq, enum ixp23xx_irq_type type)
 289 {
 290         switch (type) {
 291         case IXP23XX_IRQ_LEVEL:
 292                 set_irq_chip(irq, &ixp23xx_irq_level_chip);
 293                 set_irq_handler(irq, handle_level_irq);
 294                 break;
 295         case IXP23XX_IRQ_EDGE:
 296                 set_irq_chip(irq, &ixp23xx_irq_edge_chip);
 297                 set_irq_handler(irq, handle_edge_irq);
 298                 break;
 299         }
 300         set_irq_flags(irq, IRQF_VALID);
 301 }
 302
 303 void __init ixp23xx_init_irq(void)
 304 {
 305         int irq;
 306
 307         /* Route everything to IRQ */
 308         *IXP23XX_INTR_SEL1 = 0x0;
 309         *IXP23XX_INTR_SEL2 = 0x0;
 310         *IXP23XX_INTR_SEL3 = 0x0;
 311         *IXP23XX_INTR_SEL4 = 0x0;
 312
 313         /* Mask all sources */
 314         *IXP23XX_INTR_EN1 = 0x0;
 315         *IXP23XX_INTR_EN2 = 0x0;
 316         *IXP23XX_INTR_EN3 = 0x0;
 317         *IXP23XX_INTR_EN4 = 0x0;
 318
 319         /*
 320          * Configure all IRQs for level-sensitive operation
 321          */
 322         for (irq = 0; irq <= NUM_IXP23XX_RAW_IRQS; irq++) {
 323                 ixp23xx_config_irq(irq, IXP23XX_IRQ_LEVEL);
 324         }
 325
 326         for (irq = IRQ_IXP23XX_INTA; irq <= IRQ_IXP23XX_INTB; irq++) {
 327                 set_irq_chip(irq, &ixp23xx_pci_irq_chip);
 328                 set_irq_handler(irq, handle_level_irq);
 329                 set_irq_flags(irq, IRQF_VALID);
 330         }
 331
 332         set_irq_chained_handler(IRQ_IXP23XX_PCI_INT_RPH, pci_handler);
 333 }
 334
 335
 336 /*************************************************************************
 337  * Timer-tick functions for IXP23xx
 338  *************************************************************************/
 339 #define CLOCK_TICKS_PER_USEC    (CLOCK_TICK_RATE / USEC_PER_SEC)
 340
 341 static unsigned long next_jiffy_time;
 342
 343 static unsigned long
 344 ixp23xx_gettimeoffset(void)
 345 {
 346         unsigned long elapsed;
 347
 348         elapsed = *IXP23XX_TIMER_CONT - (next_jiffy_time - LATCH);
 349
 350         return elapsed / CLOCK_TICKS_PER_USEC;
 351 }
 352
 353 static irqreturn_t
 354 ixp23xx_timer_interrupt(int irq, void *dev_id)
 355 {
 356         /* Clear Pending Interrupt by writing '1' to it */
 357         *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
 358         while ((signed long)(*IXP23XX_TIMER_CONT - next_jiffy_time) >= LATCH) {
 359                 timer_tick();
 360                 next_jiffy_time += LATCH;
 361         }
 362
 363         return IRQ_HANDLED;
 364 }
 365
 366 static struct irqaction ixp23xx_timer_irq = {
 367         .name           = "IXP23xx Timer Tick",
 368         .handler        = ixp23xx_timer_interrupt,
 369         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 370 };
 371
 372 void __init ixp23xx_init_timer(void)
 373 {
 374         /* Clear Pending Interrupt by writing '1' to it */
 375         *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
 376
 377         /* Setup the Timer counter value */
 378         *IXP23XX_TIMER1_RELOAD =
 379                 (LATCH & ~IXP23XX_TIMER_RELOAD_MASK) | IXP23XX_TIMER_ENABLE;
 380
 381         *IXP23XX_TIMER_CONT = 0;
 382         next_jiffy_time = LATCH;
 383
 384         /* Connect the interrupt handler and enable the interrupt */
 385         setup_irq(IRQ_IXP23XX_TIMER1, &ixp23xx_timer_irq);
 386 }
 387
 388 struct sys_timer ixp23xx_timer = {
 389         .init           = ixp23xx_init_timer,
 390         .offset         = ixp23xx_gettimeoffset,
 391 };
 392
 393
 394 /*************************************************************************
 395  * IXP23xx Platform Initialization
 396  *************************************************************************/
 397 static struct resource ixp23xx_uart_resources[] = {
 398         {
 399                 .start          = IXP23XX_UART1_PHYS,
 400                 .end            = IXP23XX_UART1_PHYS + 0x0fff,
 401                 .flags          = IORESOURCE_MEM
 402         }, {
 403                 .start          = IXP23XX_UART2_PHYS,
 404                 .end            = IXP23XX_UART2_PHYS + 0x0fff,
 405                 .flags          = IORESOURCE_MEM
 406         }
 407 };
 408
 409 static struct plat_serial8250_port ixp23xx_uart_data[] = {
 410         {
 411                 .mapbase        = IXP23XX_UART1_PHYS,
 412                 .membase        = (char *)(IXP23XX_UART1_VIRT + 3),
 413                 .irq            = IRQ_IXP23XX_UART1,
 414                 .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 415                 .iotype         = UPIO_MEM,
 416                 .regshift       = 2,
 417                 .uartclk        = IXP23XX_UART_XTAL,
 418         }, {
 419                 .mapbase        = IXP23XX_UART2_PHYS,
 420                 .membase        = (char *)(IXP23XX_UART2_VIRT + 3),
 421                 .irq            = IRQ_IXP23XX_UART2,
 422                 .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 423                 .iotype         = UPIO_MEM,
 424                 .regshift       = 2,
 425                 .uartclk        = IXP23XX_UART_XTAL,
 426         },
 427         { },
 428 };
 429
 430 static struct platform_device ixp23xx_uart = {
 431         .name                   = "serial8250",
 432         .id                     = 0,
 433         .dev.platform_data      = ixp23xx_uart_data,
 434         .num_resources          = 2,
 435         .resource               = ixp23xx_uart_resources,
 436 };
 437
 438 static struct platform_device *ixp23xx_devices[] __initdata = {
 439         &ixp23xx_uart,
 440 };
 441
 442 void __init ixp23xx_sys_init(void)
 443 {
 444         *IXP23XX_EXP_UNIT_FUSE |= 0xf;
 445         platform_add_devices(ixp23xx_devices, ARRAY_SIZE(ixp23xx_devices));
 446 }