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 static DEFINE_SPINLOCK(ixp2000_slowport_lock);
  44 static unsigned long ixp2000_slowport_irq_flags;
  45
  46 /*************************************************************************
  47  * Slowport access routines
  48  *************************************************************************/
  49 void ixp2000_acquire_slowport(struct slowport_cfg *new_cfg, struct slowport_cfg *old_cfg)
  50 {
  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_write(IXP2000_SLOWPORT_ADC, new_cfg->ADC);
  65 }
  66
  67 void 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_write(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  *************************************************************************/
  82 static struct map_desc ixp2000_io_desc[] __initdata = {
  83         {
  84                 .virtual        = IXP2000_CAP_VIRT_BASE,
  85                 .physical       = IXP2000_CAP_PHYS_BASE,
  86                 .length         = IXP2000_CAP_SIZE,
  87                 .type           = MT_DEVICE
  88         }, {
  89                 .virtual        = IXP2000_INTCTL_VIRT_BASE,
  90                 .physical       = IXP2000_INTCTL_PHYS_BASE,
  91                 .length         = IXP2000_INTCTL_SIZE,
  92                 .type           = MT_DEVICE
  93         }, {
  94                 .virtual        = IXP2000_PCI_CREG_VIRT_BASE,
  95                 .physical       = IXP2000_PCI_CREG_PHYS_BASE,
  96                 .length         = IXP2000_PCI_CREG_SIZE,
  97                 .type           = MT_DEVICE
  98         }, {
  99                 .virtual        = IXP2000_PCI_CSR_VIRT_BASE,
 100                 .physical       = IXP2000_PCI_CSR_PHYS_BASE,
 101                 .length         = IXP2000_PCI_CSR_SIZE,
 102                 .type           = MT_DEVICE
 103         }, {
 104                 .virtual        = IXP2000_PCI_IO_VIRT_BASE,
 105                 .physical       = IXP2000_PCI_IO_PHYS_BASE,
 106                 .length         = IXP2000_PCI_IO_SIZE,
 107                 .type           = MT_DEVICE
 108         }, {
 109                 .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
 110                 .physical       = IXP2000_PCI_CFG0_PHYS_BASE,
 111                 .length         = IXP2000_PCI_CFG0_SIZE,
 112                 .type           = MT_DEVICE
 113         }, {
 114                 .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
 115                 .physical       = IXP2000_PCI_CFG1_PHYS_BASE,
 116                 .length         = IXP2000_PCI_CFG1_SIZE,
 117                 .type           = MT_DEVICE
 118         }
 119 };
 120
 121 static struct uart_port ixp2000_serial_port = {
 122         .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
 123         .mapbase        = IXP2000_UART_PHYS_BASE + 3,
 124         .irq            = IRQ_IXP2000_UART,
 125         .flags          = UPF_SKIP_TEST,
 126         .iotype         = UPIO_MEM,
 127         .regshift       = 2,
 128         .uartclk        = 50000000,
 129         .line           = 0,
 130         .type           = PORT_XSCALE,
 131         .fifosize       = 16
 132 };
 133
 134 void __init ixp2000_map_io(void)
 135 {
 136         extern unsigned int processor_id;
 137
 138         /*
 139          * On IXP2400 CPUs we need to use MT_IXP2000_DEVICE for
 140          * tweaking the PMDs so XCB=101. On IXP2800s we use the normal
 141          * PMD flags.
 142          */
 143         if ((processor_id & 0xfffffff0) == 0x69054190) {
 144                 int i;
 145
 146                 printk(KERN_INFO "Enabling IXP2400 erratum #66 workaround\n");
 147
 148                 for(i=0;i<ARRAY_SIZE(ixp2000_io_desc);i++)
 149                         ixp2000_io_desc[i].type = MT_IXP2000_DEVICE;
 150         }
 151
 152         iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
 153         early_serial_setup(&ixp2000_serial_port);
 154
 155         /* Set slowport to 8-bit mode.  */
 156         ixp2000_reg_write(IXP2000_SLOWPORT_FRM, 1);
 157 }
 158
 159 /*************************************************************************
 160  * Timer-tick functions for IXP2000
 161  *************************************************************************/
 162 static unsigned ticks_per_jiffy;
 163 static unsigned ticks_per_usec;
 164 static unsigned next_jiffy_time;
 165 static volatile unsigned long *missing_jiffy_timer_csr;
 166
 167 unsigned long ixp2000_gettimeoffset (void)
 168 {
 169         unsigned long offset;
 170
 171         offset = next_jiffy_time - *missing_jiffy_timer_csr;
 172
 173         return offset / ticks_per_usec;
 174 }
 175
 176 static int ixp2000_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 177 {
 178         write_seqlock(&xtime_lock);
 179
 180         /* clear timer 1 */
 181         ixp2000_reg_write(IXP2000_T1_CLR, 1);
 182
 183         while ((next_jiffy_time - *missing_jiffy_timer_csr) > ticks_per_jiffy) {
 184                 timer_tick(regs);
 185                 next_jiffy_time -= ticks_per_jiffy;
 186         }
 187
 188         write_sequnlock(&xtime_lock);
 189
 190         return IRQ_HANDLED;
 191 }
 192
 193 static struct irqaction ixp2000_timer_irq = {
 194         .name           = "IXP2000 Timer Tick",
 195         .flags          = SA_INTERRUPT,
 196         .handler        = ixp2000_timer_interrupt
 197 };
 198
 199 void __init ixp2000_init_time(unsigned long tick_rate)
 200 {
 201         ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
 202         ticks_per_usec = tick_rate / 1000000;
 203
 204         /*
 205          * We use timer 1 as our timer interrupt.
 206          */
 207         ixp2000_reg_write(IXP2000_T1_CLR, 0);
 208         ixp2000_reg_write(IXP2000_T1_CLD, ticks_per_jiffy - 1);
 209         ixp2000_reg_write(IXP2000_T1_CTL, (1 << 7));
 210
 211         /*
 212          * We use a second timer as a monotonic counter for tracking
 213          * missed jiffies.  The IXP2000 has four timers, but if we're
 214          * on an A-step IXP2800, timer 2 and 3 don't work, so on those
 215          * chips we use timer 4.  Timer 4 is the only timer that can
 216          * be used for the watchdog, so we use timer 2 if we're on a
 217          * non-buggy chip.
 218          */
 219         if ((*IXP2000_PRODUCT_ID & 0x001ffef0) == 0x00000000) {
 220                 printk(KERN_INFO "Enabling IXP2800 erratum #25 workaround\n");
 221
 222                 ixp2000_reg_write(IXP2000_T4_CLR, 0);
 223                 ixp2000_reg_write(IXP2000_T4_CLD, -1);
 224                 ixp2000_reg_write(IXP2000_T4_CTL, (1 << 7));
 225                 missing_jiffy_timer_csr = IXP2000_T4_CSR;
 226         } else {
 227                 ixp2000_reg_write(IXP2000_T2_CLR, 0);
 228                 ixp2000_reg_write(IXP2000_T2_CLD, -1);
 229                 ixp2000_reg_write(IXP2000_T2_CTL, (1 << 7));
 230                 missing_jiffy_timer_csr = IXP2000_T2_CSR;
 231         }
 232         next_jiffy_time = 0xffffffff;
 233
 234         /* register for interrupt */
 235         setup_irq(IRQ_IXP2000_TIMER1, &ixp2000_timer_irq);
 236 }
 237
 238 /*************************************************************************
 239  * GPIO helpers
 240  *************************************************************************/
 241 static unsigned long GPIO_IRQ_rising_edge;
 242 static unsigned long GPIO_IRQ_falling_edge;
 243 static unsigned long GPIO_IRQ_level_low;
 244 static unsigned long GPIO_IRQ_level_high;
 245
 246 void gpio_line_config(int line, int style)
 247 {
 248         unsigned long flags;
 249
 250         local_irq_save(flags);
 251
 252         if(style == GPIO_OUT) {
 253                 /* if it's an output, it ain't an interrupt anymore */
 254                 ixp2000_reg_write(IXP2000_GPIO_PDSR, (1 << line));
 255                 GPIO_IRQ_falling_edge &= ~(1 << line);
 256                 GPIO_IRQ_rising_edge &= ~(1 << line);
 257                 GPIO_IRQ_level_low &= ~(1 << line);
 258                 GPIO_IRQ_level_high &= ~(1 << line);
 259                 ixp2000_reg_write(IXP2000_GPIO_FEDR, GPIO_IRQ_falling_edge);
 260                 ixp2000_reg_write(IXP2000_GPIO_REDR, GPIO_IRQ_rising_edge);
 261                 ixp2000_reg_write(IXP2000_GPIO_LSHR, GPIO_IRQ_level_high);
 262                 ixp2000_reg_write(IXP2000_GPIO_LSLR, GPIO_IRQ_level_low);
 263                 irq_desc[line+IRQ_IXP2000_GPIO0].valid = 0;
 264         } else if(style == GPIO_IN) {
 265                 ixp2000_reg_write(IXP2000_GPIO_PDCR, (1 << line));
 266         }
 267
 268         local_irq_restore(flags);
 269 }
 270
 271
 272 /*************************************************************************
 273  * IRQ handling IXP2000
 274  *************************************************************************/
 275 static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
 276 {
 277         int i;
 278         unsigned long status = *IXP2000_GPIO_INST;
 279
 280         for (i = 0; i <= 7; i++) {
 281                 if (status & (1<<i)) {
 282                         desc = irq_desc + i + IRQ_IXP2000_GPIO0;
 283                         desc->handle(i + IRQ_IXP2000_GPIO0, desc, regs);
 284                 }
 285         }
 286 }
 287
 288 static void ixp2000_GPIO_irq_mask_ack(unsigned int irq)
 289 {
 290         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 291         ixp2000_reg_write(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
 292 }
 293
 294 static void ixp2000_GPIO_irq_mask(unsigned int irq)
 295 {
 296         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 297 }
 298
 299 static void ixp2000_GPIO_irq_unmask(unsigned int irq)
 300 {
 301         ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 302 }
 303
 304 static struct irqchip ixp2000_GPIO_irq_chip = {
 305         .ack    = ixp2000_GPIO_irq_mask_ack,
 306         .mask   = ixp2000_GPIO_irq_mask,
 307         .unmask = ixp2000_GPIO_irq_unmask
 308 };
 309
 310 static void ixp2000_pci_irq_mask(unsigned int irq)
 311 {
 312         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 313         if (irq == IRQ_IXP2000_PCIA)
 314                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
 315         else if (irq == IRQ_IXP2000_PCIB)
 316                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 27)));
 317 }
 318
 319 static void ixp2000_pci_irq_unmask(unsigned int irq)
 320 {
 321         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 322         if (irq == IRQ_IXP2000_PCIA)
 323                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
 324         else if (irq == IRQ_IXP2000_PCIB)
 325                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 27)));
 326 }
 327
 328 static struct irqchip ixp2000_pci_irq_chip = {
 329         .ack    = ixp2000_pci_irq_mask,
 330         .mask   = ixp2000_pci_irq_mask,
 331         .unmask = ixp2000_pci_irq_unmask
 332 };
 333
 334 static void ixp2000_irq_mask(unsigned int irq)
 335 {
 336         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
 337 }
 338
 339 static void ixp2000_irq_unmask(unsigned int irq)
 340 {
 341         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET,  (1 << irq));
 342 }
 343
 344 static struct irqchip ixp2000_irq_chip = {
 345         .ack    = ixp2000_irq_mask,
 346         .mask   = ixp2000_irq_mask,
 347         .unmask = ixp2000_irq_unmask
 348 };
 349
 350 void __init ixp2000_init_irq(void)
 351 {
 352         int irq;
 353
 354         /*
 355          * Mask all sources
 356          */
 357         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
 358         ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
 359
 360         /* clear all GPIO edge/level detects */
 361         ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
 362         ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
 363         ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
 364         ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
 365         ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
 366
 367         /* clear PCI interrupt sources */
 368         ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
 369
 370         /*
 371          * Certain bits in the IRQ status register of the
 372          * IXP2000 are reserved. Instead of trying to map
 373          * things non 1:1 from bit position to IRQ number,
 374          * we mark the reserved IRQs as invalid. This makes
 375          * our mask/unmask code much simpler.
 376          */
 377         for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
 378                 if((1 << irq) & IXP2000_VALID_IRQ_MASK) {
 379                         set_irq_chip(irq, &ixp2000_irq_chip);
 380                         set_irq_handler(irq, do_level_IRQ);
 381                         set_irq_flags(irq, IRQF_VALID);
 382                 } else set_irq_flags(irq, 0);
 383         }
 384
 385         /*
 386          * GPIO IRQs are invalid until someone sets the interrupt mode
 387          * by calling gpio_line_set();
 388          */
 389         for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
 390                 set_irq_chip(irq, &ixp2000_GPIO_irq_chip);
 391                 set_irq_handler(irq, do_level_IRQ);
 392                 set_irq_flags(irq, 0);
 393         }
 394         set_irq_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
 395
 396         /*
 397          * Enable PCI irqs.  The actual PCI[AB] decoding is done in
 398          * entry-macro.S, so we don't need a chained handler for the
 399          * PCI interrupt source.
 400          */
 401         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
 402         for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
 403                 set_irq_chip(irq, &ixp2000_pci_irq_chip);
 404                 set_irq_handler(irq, do_level_IRQ);
 405                 set_irq_flags(irq, IRQF_VALID);
 406         }
 407 }
 408