arch/arm/kernel/hw-sa1100.c

   1 /*
   2  * arch/arm/kernel/hw-sa1100.c
   3  *
   4  * SA1100-dependent machine specifics
   5  *
   6  * Copyright (C) 2000 Nicolas Pitre <nico@cam.org>
   7  *
   8  * This will certainly contain more stuff with time... like power management,
   9  * special hardware autodetection, etc.
  10  *
  11  */
  12 #include <linux/config.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/sched.h>
  17
  18 #include <asm/delay.h>
  19 #include <asm/hardware.h>
  20
  21
  22 /*
  23  * SA1100 GPIO edge detection for IRQs:
  24  * IRQs are generated on Falling-Edge, Rising-Edge, or both.
  25  * This must be called *before* the appropriate IRQ is registered.
  26  * Use this instead of directly setting GRER/GFER.
  27  */
  28
  29 int GPIO_IRQ_rising_edge;
  30 int GPIO_IRQ_falling_edge;
  31
  32 void set_GPIO_IRQ_edge( int gpio_mask, int edge )
  33 {
  34         if( edge & GPIO_FALLING_EDGE )
  35                 GPIO_IRQ_falling_edge |= gpio_mask;
  36         else
  37                 GPIO_IRQ_falling_edge &= ~gpio_mask;
  38         if( edge & GPIO_RISING_EDGE )
  39                 GPIO_IRQ_rising_edge |= gpio_mask;
  40         else
  41                 GPIO_IRQ_rising_edge &= ~gpio_mask;
  42 }
  43
  44 EXPORT_SYMBOL(set_GPIO_IRQ_edge);
  45
  46
  47 #ifdef CONFIG_SA1100_ASSABET
  48
  49 unsigned long BCR_value = BCR_DB1110;
  50 unsigned long SCR_value = SCR_INIT;
  51 EXPORT_SYMBOL(BCR_value);
  52 EXPORT_SYMBOL(SCR_value);
  53
  54 /*
  55  * Read System Configuration "Register"
  56  * (taken from "Intel StrongARM SA-1110 Microprocessor Development Board
  57  * User's Guide", section 4.4.1)
  58  *
  59  * This same scan is performed in arch/arm/boot/compressed/head-sa1100.S
  60  * to set up the serial port for decompression status messages. We
  61  * repeat it here because the kernel may not be loaded as a zImage, and
  62  * also because it's a hassle to communicate the SCR value to the kernel
  63  * from the decompressor.
  64  */
  65
  66 void __init get_assabet_scr(void)
  67 {
  68         unsigned long flags, scr, i;
  69
  70         save_flags_cli(flags);
  71         GPDR |= 0x3fc;                  /* Configure GPIO 9:2 as outputs */
  72         GPSR = 0x3fc;                   /* Write 0xFF to GPIO 9:2 */
  73         GPDR &= ~(0x3fc);               /* Configure GPIO 9:2 as inputs */
  74         for(i = 100; i--; scr = GPLR);  /* Read GPIO 9:2 */
  75         GPDR |= 0x3fc;                  /*  restore correct pin direction */
  76         restore_flags(flags);
  77         scr &= 0x3fc;                   /* save as system configuration byte. */
  78
  79         SCR_value = scr;
  80 }
  81
  82 #endif  /* CONFIG_SA1100_ASSABET */
  83
  84 /*
  85  * Bitsy has extended, write-only memory-mapped GPIO's
  86  */
  87 #if defined(CONFIG_SA1100_BITSY)
  88 static int bitsy_egpio = EGPIO_BITSY_RS232_ON;
  89 void clr_bitsy_egpio(unsigned long x)
  90 {
  91   bitsy_egpio &= ~x;
  92   *(volatile int *)0xdc000000 = bitsy_egpio;
  93 }
  94 void set_bitsy_egpio(unsigned long x)
  95 {
  96   bitsy_egpio |= x;
  97   *(volatile int *)0xdc000000 = bitsy_egpio;
  98 }
  99 EXPORT_SYMBOL(clr_bitsy_egpio);
 100 EXPORT_SYMBOL(set_bitsy_egpio);
 101 #endif
 102
 103 #ifdef CONFIG_SA1111
 104
 105 void __init sa1111_init(void){
 106   unsigned long id=SKID;
 107
 108   if((id & SKID_ID_MASK) == SKID_SA1111_ID)
 109     printk(KERN_INFO "SA-1111 Microprocessor Companion Chip: "
 110            "silicon revision %x, metal revision %x\n",
 111            (id & SKID_SIREV_MASK)>>4, (id & SKID_MTREV_MASK));
 112   else {
 113     printk(KERN_ERR "Could not detect SA-1111!\n");
 114     return;
 115   }
 116
 117   /* First, set up the 3.6864MHz clock on GPIO 27 for the SA-1111:
 118    * (SA-1110 Developer's Manual, section 9.1.2.1)
 119    */
 120   GAFR |= GPIO_GPIO27;
 121   GPDR |= GPIO_GPIO27;
 122   TUCR = TUCR_3_6864MHz;
 123
 124   /* Now, set up the PLL and RCLK in the SA-1111: */
 125   SKCR = SKCR_PLL_BYPASS | SKCR_RDYEN | SKCR_OE_EN;
 126   udelay(100);
 127   SKCR = SKCR_PLL_BYPASS | SKCR_RCLKEN | SKCR_RDYEN | SKCR_OE_EN;
 128
 129   /* SA-1111 Register Access Bus should now be available. Clocks for
 130    * any other SA-1111 functional blocks must be enabled separately
 131    * using the SKPCR.
 132    */
 133 }
 134
 135 #endif
 136
 137
 138 static void __init hw_sa1100_init(void)
 139 {
 140         if( machine_is_assabet() ){
 141                 if(machine_has_neponset()){
 142 #ifdef CONFIG_ASSABET_NEPONSET
 143                         LEDS = WHOAMI;
 144                         sa1111_init();
 145 #else
 146                         printk( "Warning: Neponset detected but full support "
 147                                 "hasn't been configured in the kernel\n" );
 148 #endif
 149                 }
 150         }
 151 }
 152
 153 module_init(hw_sa1100_init);