arch/sh/boards/superh/microdev/led.c

   1 /*
   2  * linux/arch/sh/kernel/led_microdev.c
   3  *
   4  * Copyright (C) 2002 Stuart Menefy <stuart.menefy@st.com>
   5  * Copyright (C) 2003 Richard Curnow (Richard.Curnow@superh.com)
   6  *
   7  * May be copied or modified under the terms of the GNU General Public
   8  * License.  See linux/COPYING for more information.
   9  *
  10  */
  11
  12 #include <linux/config.h>
  13 #include <asm/io.h>
  14
  15 #define LED_REGISTER 0xa6104d20
  16
  17 static void mach_led_d9(int value)
  18 {
  19         unsigned long reg;
  20         reg = ctrl_inl(LED_REGISTER);
  21         reg &= ~1;
  22         reg |= (value & 1);
  23         ctrl_outl(reg, LED_REGISTER);
  24         return;
  25 }
  26
  27 static void mach_led_d10(int value)
  28 {
  29         unsigned long reg;
  30         reg = ctrl_inl(LED_REGISTER);
  31         reg &= ~2;
  32         reg |= ((value & 1) << 1);
  33         ctrl_outl(reg, LED_REGISTER);
  34         return;
  35 }
  36
  37
  38 #ifdef CONFIG_HEARTBEAT
  39 #include <linux/sched.h>
  40
  41 static unsigned char banner_table[] = {
  42         0x11, 0x01, 0x11, 0x01, 0x11, 0x03,
  43         0x11, 0x01, 0x11, 0x01, 0x13, 0x03,
  44         0x11, 0x01, 0x13, 0x01, 0x13, 0x01, 0x11, 0x03,
  45         0x11, 0x03,
  46         0x11, 0x01, 0x13, 0x01, 0x11, 0x03,
  47         0x11, 0x01, 0x11, 0x01, 0x11, 0x01, 0x11, 0x07,
  48         0x13, 0x01, 0x13, 0x03,
  49         0x11, 0x01, 0x11, 0x03,
  50         0x13, 0x01, 0x11, 0x01, 0x13, 0x01, 0x11, 0x03,
  51         0x11, 0x01, 0x13, 0x01, 0x11, 0x03,
  52         0x13, 0x01, 0x13, 0x01, 0x13, 0x03,
  53         0x13, 0x01, 0x11, 0x01, 0x11, 0x03,
  54         0x11, 0x03,
  55         0x11, 0x01, 0x11, 0x01, 0x11, 0x01, 0x13, 0x07,
  56         0xff
  57 };
  58
  59 static void banner(void)
  60 {
  61         static int pos = 0;
  62         static int count = 0;
  63
  64         if (count) {
  65                 count--;
  66         } else {
  67                 int val = banner_table[pos];
  68                 if (val == 0xff) {
  69                         pos = 0;
  70                         val = banner_table[pos];
  71                 }
  72                 pos++;
  73                 mach_led_d10((val >> 4) & 1);
  74                 count = 10 * (val & 0xf);
  75         }
  76 }
  77
  78 /* From heartbeat_harp in the stboards directory */
  79 /* acts like an actual heart beat -- ie thump-thump-pause... */
  80 void microdev_heartbeat(void)
  81 {
  82         static unsigned cnt = 0, period = 0, dist = 0;
  83
  84         if (cnt == 0 || cnt == dist)
  85                 mach_led_d9(1);
  86         else if (cnt == 7 || cnt == dist+7)
  87                 mach_led_d9(0);
  88
  89         if (++cnt > period) {
  90                 cnt = 0;
  91                 /* The hyperbolic function below modifies the heartbeat period
  92                  * length in dependency of the current (5min) load. It goes
  93                  * through the points f(0)=126, f(1)=86, f(5)=51,
  94                  * f(inf)->30. */
  95                 period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30;
  96                 dist = period / 4;
  97         }
  98
  99         banner();
 100 }
 101
 102 #endif