software/libbase/system.c

   1 /*
   2  * Milkymist SoC (Software)
   3  * Copyright (C) 2007, 2008, 2009, 2012 Sebastien Bourdeauducq
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, version 3 of the License.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <irq.h>
  19 #include <uart.h>
  20 #include <hw/sysctl.h>
  21
  22 #include <system.h>
  23
  24 void flush_cpu_icache(void)
  25 {
  26         asm volatile(
  27                 "wcsr ICC, r0\n"
  28                 "nop\n"
  29                 "nop\n"
  30                 "nop\n"
  31                 "nop\n"
  32         );
  33 }
  34
  35 void flush_cpu_dcache(void)
  36 {
  37         asm volatile(
  38                 "wcsr DCC, r0\n"
  39                 "nop\n"
  40         );
  41 }
  42
  43 __attribute__((noreturn)) void reboot(void)
  44 {
  45         uart_sync();
  46         irq_setmask(0);
  47         irq_enable(0);
  48         CSR_SYSTEM_ID = 1; /* Writing to CSR_SYSTEM_ID causes a system reset */
  49         while(1);
  50 }
  51
  52 static void icap_write(int val, unsigned int w)
  53 {
  54         while(!(CSR_ICAP & ICAP_READY));
  55         if(!val)
  56                 w |= ICAP_CE|ICAP_WRITE;
  57         CSR_ICAP = w;
  58 }
  59
  60 __attribute__((noreturn)) void reconf(void)
  61 {
  62         uart_sync();
  63         irq_setmask(0);
  64         irq_enable(0);
  65         icap_write(0, 0xffff); /* dummy word */
  66         icap_write(0, 0xffff); /* dummy word */
  67         icap_write(0, 0xffff); /* dummy word */
  68         icap_write(0, 0xffff); /* dummy word */
  69         icap_write(1, 0xaa99); /* sync word part 1 */
  70         icap_write(1, 0x5566); /* sync word part 2 */
  71         icap_write(1, 0x30a1); /* write to command register */
  72         icap_write(1, 0x0000); /* null command */
  73         icap_write(1, 0x30a1); /* write to command register */
  74         icap_write(1, 0x000e); /* reboot command */
  75         icap_write(1, 0x2000); /* NOP */
  76         icap_write(1, 0x2000); /* NOP */
  77         icap_write(1, 0x2000); /* NOP */
  78         icap_write(1, 0x2000); /* NOP */
  79         icap_write(0, 0x1111); /* NULL */
  80         icap_write(0, 0xffff); /* dummy word */
  81         while(1);
  82 }