kernel/arch/earm/bsp/ti/omap_reset.c

   1 #include <assert.h>
   2 #include <sys/types.h>
   3 #include <machine/cpu.h>
   4 #include <minix/type.h>
   5 #include <minix/board.h>
   6 #include <io.h>
   7
   8 #include "kernel/kernel.h"
   9 #include "kernel/proc.h"
  10 #include "kernel/vm.h"
  11 #include "kernel/proto.h"
  12 #include "arch_proto.h"
  13 #include "bsp_reset.h"
  14
  15 #include "omap_rtc.h"
  16
  17 #define AM335X_CM_BASE 0x44E00000
  18 #define AM335X_CM_SIZE 0x1000
  19
  20 #define AM335X_PRM_DEVICE_OFFSET 0xf00
  21 #define AM335X_PRM_RSTCTRL_REG 0x00
  22 #define AM335X_RST_GLOBAL_WARM_SW_BIT 0
  23
  24 #define DM37XX_CM_BASE 0x48307000
  25 #define DM37XX_CM_SIZE 0x1000
  26 #define DM37XX_PRM_RSTCTRL_REG 0x250
  27 #define DM37XX_RST_DPLL3_BIT 2
  28
  29 struct omap_reset
  30 {
  31         vir_bytes base;
  32         vir_bytes size;
  33 };
  34
  35 static struct omap_reset omap_reset;
  36
  37 static kern_phys_map reset_phys_map;
  38
  39 void
  40 bsp_reset_init(void)
  41 {
  42         if (BOARD_IS_BBXM(machine.board_id)) {
  43                 omap_reset.base = DM37XX_CM_BASE;
  44                 omap_reset.size = DM37XX_CM_SIZE;
  45         } else if (BOARD_IS_BB(machine.board_id)) {
  46                 omap_reset.base = AM335X_CM_BASE;
  47                 omap_reset.size = AM335X_CM_SIZE;
  48         }
  49
  50         kern_phys_map_ptr(omap_reset.base, omap_reset.size,
  51             VMMF_UNCACHED | VMMF_WRITE,
  52             &reset_phys_map, (vir_bytes) & omap_reset.base);
  53 }
  54
  55 void
  56 bsp_reset(void)
  57 {
  58         if (BOARD_IS_BBXM(machine.board_id)) {
  59                 mmio_set((omap_reset.base + DM37XX_PRM_RSTCTRL_REG),
  60                     (1 << DM37XX_RST_DPLL3_BIT));
  61         } else if (BOARD_IS_BB(machine.board_id)) {
  62                 mmio_set((omap_reset.base + AM335X_PRM_DEVICE_OFFSET +
  63                         AM335X_PRM_RSTCTRL_REG),
  64                     (1 << AM335X_RST_GLOBAL_WARM_SW_BIT));
  65         }
  66 }
  67
  68 void
  69 bsp_poweroff(void)
  70 {
  71
  72 /*
  73  * The am335x can signal an external power management chip to cut the power
  74  * by toggling the PMIC_POWER_EN pin. It might fail if there isn't an
  75  * external PMIC or if the PMIC hasn't been configured to respond to toggles.
  76  * The only way to pull the pin low is via ALARM2 (see TRM 20.3.3.8).
  77  * At this point PM should have already signaled readclock to set the alarm.
  78  */
  79         if (BOARD_IS_BB(machine.board_id)) {
  80                 /* rtc was frozen to prevent premature power-off, unfreeze it
  81                  * now */
  82                 omap3_rtc_run();
  83
  84                 /* wait for the alarm to go off and PMIC to disable power to
  85                  * SoC */
  86                 while (1);
  87         }
  88 }