minix/lib/libclkconf/clkconf.c

   1 /* kernel headers */
   2 #include <minix/syslib.h>
   3 #include <minix/drvlib.h>
   4 #include <minix/log.h>
   5 #include <minix/mmio.h>
   6 #include <minix/clkconf.h>
   7 #include <minix/type.h>
   8 #include <minix/board.h>
   9
  10 /* system headers */
  11 #include <sys/mman.h>
  12 #include <sys/types.h>
  13
  14 /* usr headers */
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <stdarg.h>
  18 #include <string.h>
  19 #include <errno.h>
  20 #include <assert.h>
  21
  22 /* used for logging */
  23 static struct log log = {
  24         .name = "omap_clkconf",
  25         .log_level = LEVEL_INFO,
  26         .log_func = default_log
  27 };
  28
  29 #define DM37XX_CM_BASE 0x48004000
  30 #define AM335X_CM_BASE 0x44E00000
  31
  32 static u32_t base = 0;
  33 static u32_t use_count = 0;
  34
  35 int
  36 clkconf_init()
  37 {
  38         use_count++;
  39         struct machine machine;
  40         sys_getmachine(&machine);
  41         u32_t cm_base = 0;
  42
  43
  44         if (base != 0) {
  45                 /* when used in a library we can't guaranty we only call this
  46                  * method once */
  47                 log_trace(&log, "Called %d times\n", use_count);
  48                 return OK;
  49         }
  50
  51         if (BOARD_IS_BBXM(machine.board_id)){
  52                 cm_base = DM37XX_CM_BASE;
  53         } else if (BOARD_IS_BB(machine.board_id)){
  54                 cm_base = AM335X_CM_BASE;
  55         }
  56         struct minix_mem_range mr;
  57         mr.mr_base = cm_base;
  58         mr.mr_limit = cm_base + 0x1000;
  59
  60         if (sys_privctl(SELF, SYS_PRIV_ADD_MEM, &mr) != 0) {
  61                 log_warn(&log, "Unable to request permission to map memory\n");
  62                 return EPERM;
  63         }
  64
  65         base = (uint32_t) vm_map_phys(SELF, (void *) cm_base, 0x1000);
  66
  67         if (base == (uint32_t) MAP_FAILED) {
  68                 log_warn(&log, "Unable to map GPIO memory\n");
  69                 return EPERM;
  70         }
  71         return OK;
  72 }
  73
  74 int
  75 clkconf_set(u32_t clk, u32_t mask, u32_t value)
  76 {
  77         set32(base + clk, mask, value);
  78         return OK;
  79 }
  80
  81 int
  82 clkconf_release()
  83 {
  84         assert(use_count > 0);
  85         use_count--;
  86         if (use_count == 0) {
  87                 vm_unmap_phys(SELF, (void *) base, 0x1000);
  88         }
  89         return OK;
  90 }