release/src-rt-6.x/linux/linux-2.6/arch/arm/mach-integrator/core.c

   1 /*
   2  *  linux/arch/arm/mach-integrator/core.c
   3  *
   4  *  Copyright (C) 2000-2003 Deep Blue Solutions Ltd
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2, as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/device.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/irq.h>
  17 #include <linux/sched.h>
  18 #include <linux/smp.h>
  19 #include <linux/termios.h>
  20 #include <linux/amba/bus.h>
  21 #include <linux/amba/serial.h>
  22
  23 #include <asm/hardware.h>
  24 #include <asm/irq.h>
  25 #include <asm/io.h>
  26 #include <asm/hardware/arm_timer.h>
  27 #include <asm/arch/cm.h>
  28 #include <asm/system.h>
  29 #include <asm/leds.h>
  30 #include <asm/mach/time.h>
  31
  32 #include "common.h"
  33
  34 static struct amba_pl010_data integrator_uart_data;
  35
  36 static struct amba_device rtc_device = {
  37         .dev            = {
  38                 .bus_id = "mb:15",
  39         },
  40         .res            = {
  41                 .start  = INTEGRATOR_RTC_BASE,
  42                 .end    = INTEGRATOR_RTC_BASE + SZ_4K - 1,
  43                 .flags  = IORESOURCE_MEM,
  44         },
  45         .irq            = { IRQ_RTCINT, NO_IRQ },
  46         .periphid       = 0x00041030,
  47 };
  48
  49 static struct amba_device uart0_device = {
  50         .dev            = {
  51                 .bus_id = "mb:16",
  52                 .platform_data = &integrator_uart_data,
  53         },
  54         .res            = {
  55                 .start  = INTEGRATOR_UART0_BASE,
  56                 .end    = INTEGRATOR_UART0_BASE + SZ_4K - 1,
  57                 .flags  = IORESOURCE_MEM,
  58         },
  59         .irq            = { IRQ_UARTINT0, NO_IRQ },
  60         .periphid       = 0x0041010,
  61 };
  62
  63 static struct amba_device uart1_device = {
  64         .dev            = {
  65                 .bus_id = "mb:17",
  66                 .platform_data = &integrator_uart_data,
  67         },
  68         .res            = {
  69                 .start  = INTEGRATOR_UART1_BASE,
  70                 .end    = INTEGRATOR_UART1_BASE + SZ_4K - 1,
  71                 .flags  = IORESOURCE_MEM,
  72         },
  73         .irq            = { IRQ_UARTINT1, NO_IRQ },
  74         .periphid       = 0x0041010,
  75 };
  76
  77 static struct amba_device kmi0_device = {
  78         .dev            = {
  79                 .bus_id = "mb:18",
  80         },
  81         .res            = {
  82                 .start  = KMI0_BASE,
  83                 .end    = KMI0_BASE + SZ_4K - 1,
  84                 .flags  = IORESOURCE_MEM,
  85         },
  86         .irq            = { IRQ_KMIINT0, NO_IRQ },
  87         .periphid       = 0x00041050,
  88 };
  89
  90 static struct amba_device kmi1_device = {
  91         .dev            = {
  92                 .bus_id = "mb:19",
  93         },
  94         .res            = {
  95                 .start  = KMI1_BASE,
  96                 .end    = KMI1_BASE + SZ_4K - 1,
  97                 .flags  = IORESOURCE_MEM,
  98         },
  99         .irq            = { IRQ_KMIINT1, NO_IRQ },
 100         .periphid       = 0x00041050,
 101 };
 102
 103 static struct amba_device *amba_devs[] __initdata = {
 104         &rtc_device,
 105         &uart0_device,
 106         &uart1_device,
 107         &kmi0_device,
 108         &kmi1_device,
 109 };
 110
 111 static int __init integrator_init(void)
 112 {
 113         int i;
 114
 115         for (i = 0; i < ARRAY_SIZE(amba_devs); i++) {
 116                 struct amba_device *d = amba_devs[i];
 117                 amba_device_register(d, &iomem_resource);
 118         }
 119
 120         return 0;
 121 }
 122
 123 arch_initcall(integrator_init);
 124
 125 /*
 126  * On the Integrator platform, the port RTS and DTR are provided by
 127  * bits in the following SC_CTRLS register bits:
 128  *        RTS  DTR
 129  *  UART0  7    6
 130  *  UART1  5    4
 131  */
 132 #define SC_CTRLC        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLC_OFFSET)
 133 #define SC_CTRLS        (IO_ADDRESS(INTEGRATOR_SC_BASE) + INTEGRATOR_SC_CTRLS_OFFSET)
 134
 135 static void integrator_uart_set_mctrl(struct amba_device *dev, void __iomem *base, unsigned int mctrl)
 136 {
 137         unsigned int ctrls = 0, ctrlc = 0, rts_mask, dtr_mask;
 138
 139         if (dev == &uart0_device) {
 140                 rts_mask = 1 << 4;
 141                 dtr_mask = 1 << 5;
 142         } else {
 143                 rts_mask = 1 << 6;
 144                 dtr_mask = 1 << 7;
 145         }
 146
 147         if (mctrl & TIOCM_RTS)
 148                 ctrlc |= rts_mask;
 149         else
 150                 ctrls |= rts_mask;
 151
 152         if (mctrl & TIOCM_DTR)
 153                 ctrlc |= dtr_mask;
 154         else
 155                 ctrls |= dtr_mask;
 156
 157         __raw_writel(ctrls, SC_CTRLS);
 158         __raw_writel(ctrlc, SC_CTRLC);
 159 }
 160
 161 static struct amba_pl010_data integrator_uart_data = {
 162         .set_mctrl = integrator_uart_set_mctrl,
 163 };
 164
 165 #define CM_CTRL IO_ADDRESS(INTEGRATOR_HDR_BASE) + INTEGRATOR_HDR_CTRL_OFFSET
 166
 167 static DEFINE_SPINLOCK(cm_lock);
 168
 169 /**
 170  * cm_control - update the CM_CTRL register.
 171  * @mask: bits to change
 172  * @set: bits to set
 173  */
 174 void cm_control(u32 mask, u32 set)
 175 {
 176         unsigned long flags;
 177         u32 val;
 178
 179         spin_lock_irqsave(&cm_lock, flags);
 180         val = readl(CM_CTRL) & ~mask;
 181         writel(val | set, CM_CTRL);
 182         spin_unlock_irqrestore(&cm_lock, flags);
 183 }
 184
 185 EXPORT_SYMBOL(cm_control);
 186
 187 /*
 188  * Where is the timer (VA)?
 189  */
 190 #define TIMER0_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000000)
 191 #define TIMER1_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000100)
 192 #define TIMER2_VA_BASE (IO_ADDRESS(INTEGRATOR_CT_BASE)+0x00000200)
 193 #define VA_IC_BASE     IO_ADDRESS(INTEGRATOR_IC_BASE)
 194
 195 /*
 196  * How long is the timer interval?
 197  */
 198 #define TIMER_INTERVAL  (TICKS_PER_uSEC * mSEC_10)
 199 #if TIMER_INTERVAL >= 0x100000
 200 #define TICKS2USECS(x)  (256 * (x) / TICKS_PER_uSEC)
 201 #elif TIMER_INTERVAL >= 0x10000
 202 #define TICKS2USECS(x)  (16 * (x) / TICKS_PER_uSEC)
 203 #else
 204 #define TICKS2USECS(x)  ((x) / TICKS_PER_uSEC)
 205 #endif
 206
 207 static unsigned long timer_reload;
 208
 209 /*
 210  * Returns number of ms since last clock interrupt.  Note that interrupts
 211  * will have been disabled by do_gettimeoffset()
 212  */
 213 unsigned long integrator_gettimeoffset(void)
 214 {
 215         unsigned long ticks1, ticks2, status;
 216
 217         /*
 218          * Get the current number of ticks.  Note that there is a race
 219          * condition between us reading the timer and checking for
 220          * an interrupt.  We get around this by ensuring that the
 221          * counter has not reloaded between our two reads.
 222          */
 223         ticks2 = readl(TIMER1_VA_BASE + TIMER_VALUE) & 0xffff;
 224         do {
 225                 ticks1 = ticks2;
 226                 status = __raw_readl(VA_IC_BASE + IRQ_RAW_STATUS);
 227                 ticks2 = readl(TIMER1_VA_BASE + TIMER_VALUE) & 0xffff;
 228         } while (ticks2 > ticks1);
 229
 230         /*
 231          * Number of ticks since last interrupt.
 232          */
 233         ticks1 = timer_reload - ticks2;
 234
 235         /*
 236          * Interrupt pending?  If so, we've reloaded once already.
 237          */
 238         if (status & (1 << IRQ_TIMERINT1))
 239                 ticks1 += timer_reload;
 240
 241         /*
 242          * Convert the ticks to usecs
 243          */
 244         return TICKS2USECS(ticks1);
 245 }
 246
 247 /*
 248  * IRQ handler for the timer
 249  */
 250 static irqreturn_t
 251 integrator_timer_interrupt(int irq, void *dev_id)
 252 {
 253         write_seqlock(&xtime_lock);
 254
 255         /*
 256          * clear the interrupt
 257          */
 258         writel(1, TIMER1_VA_BASE + TIMER_INTCLR);
 259
 260         timer_tick();
 261
 262         write_sequnlock(&xtime_lock);
 263
 264         return IRQ_HANDLED;
 265 }
 266
 267 static struct irqaction integrator_timer_irq = {
 268         .name           = "Integrator Timer Tick",
 269         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 270         .handler        = integrator_timer_interrupt,
 271 };
 272
 273 /*
 274  * Set up timer interrupt, and return the current time in seconds.
 275  */
 276 void __init integrator_time_init(unsigned long reload, unsigned int ctrl)
 277 {
 278         unsigned int timer_ctrl = TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC;
 279
 280         timer_reload = reload;
 281         timer_ctrl |= ctrl;
 282
 283         if (timer_reload > 0x100000) {
 284                 timer_reload >>= 8;
 285                 timer_ctrl |= TIMER_CTRL_DIV256;
 286         } else if (timer_reload > 0x010000) {
 287                 timer_reload >>= 4;
 288                 timer_ctrl |= TIMER_CTRL_DIV16;
 289         }
 290
 291         /*
 292          * Initialise to a known state (all timers off)
 293          */
 294         writel(0, TIMER0_VA_BASE + TIMER_CTRL);
 295         writel(0, TIMER1_VA_BASE + TIMER_CTRL);
 296         writel(0, TIMER2_VA_BASE + TIMER_CTRL);
 297
 298         writel(timer_reload, TIMER1_VA_BASE + TIMER_LOAD);
 299         writel(timer_reload, TIMER1_VA_BASE + TIMER_VALUE);
 300         writel(timer_ctrl, TIMER1_VA_BASE + TIMER_CTRL);
 301
 302         /*
 303          * Make irqs happen for the system timer
 304          */
 305         setup_irq(IRQ_TIMERINT1, &integrator_timer_irq);
 306 }