/* usc.S
*
* COPYRIGHT (c) 1989-2010.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <bspopts.h>
#include <rtems/asm.h>
#include <rtems/mips/iregdef.h>
#include <rtems/mips/idtcpu.h>
#if BSP_HAS_USC320
#include <usc.h>
#endif
/***************************************************************************
**
** The following code was added to support boards using V3 USC320
** system controller chip.
**
****************************************************************************/
/*************************************************************
* init_hbt()
* Initialize the heartbeat timer
*/
FRAME(init_hbt,sp,0,ra)
.set noreorder
la t0,SYSTEM # Unlock USC registers
li t1,0xA5
sb t1,(t0)
la t0,WD_HBI # Initialize heatbeat and watchdog timers
# (1 / 64 MHz) * 4000 * (63 + 1) = 4000.0 microseconds
# Watchdog period is heartbeat period times watchdog timer constant (bits 7 - 0)
# Watchdog period = 4000 * 5 = 20000 microseconds
li t1,(WD_EN | HBI_4000_PS | 0x00003F00 | 0x5)
# (1 / 64 MHz) * 4000 * (15 + 1) = 1000.0 microseconds
# Watchdog period is heartbeat period times watchdog timer constant (bits 7 - 0)
# Watchdog period = 1000 * 20 = 20000 microseconds
li t1,(WD_EN | HBI_4000_PS | 0x00000F00 | 0x14)
# (1 / 64 MHz) * 40000 * (15 + 1) = 10000.0 microseconds
# Watchdog period is heartbeat period times watchdog timer constant (bits 7 - 0)
# Watchdog period = 10000 * 20 = 200000 microseconds
li t1,(WD_EN | HBI_4000_PS | 0x00009600 | 0x14)
sw t1,(t0)
la t0,SYSTEM # Lock USC registers
li t1,0x60
sb t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(init_hbt)
/*************************************************************
* reset_wdt()
* Reset the watchdog timer
*/
FRAME(reset_wdt,sp,0,ra)
.set noreorder
la t0,WD_HBI+2 # Load address watchdog timer reset byte
li t1,WD_INIT
sb t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(reset_wdt)
/*************************************************************
* disable_wdt()
* Disable watchdog timer
*/
FRAME(disable_wdt,sp,0,ra)
.set noreorder
la t0,WD_HBI # Clear watchdog enable bit in control register
lw t1,(t0)
li t2,~WD_EN
and t1,t1,t2
sw t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(disable_wdt)
/*************************************************************
* enable_hbi(ints)
* Enable the heartbeat interrupt
*/
FRAME(enable_hbi,sp,0,ra)
.set noreorder
la t0,INT_CFG3 # Enable heartbeat interrupt in USC320
lw t1,(t0)
li t2,(HBI_MASK | MODE_TOTEM_POLE)
or t1,t1,t2
sw t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(enable_hbi)
/*************************************************************
* disable_hbi(ints)
* Disable the heartbeat interrupt
*/
FRAME(disable_hbi,sp,0,ra)
.set noreorder
la t0,INT_CFG3 # Disable heartbeat interrupt in USC320
lw t1,(t0)
li t2,~HBI_MASK
and t1,t1,t2
sw t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(disable_hbi)
/*************************************************************
* enable_wdi()
* Enable the watchdog interrupt
*/
FRAME(enable_wdi,sp,0,ra)
.set noreorder
la t0,INT_CFG1 # Enable watchdog interrupt in USC320
lw t1,(t0)
li t2,(WDI_MASK | MODE_TOTEM_POLE)
or t1,t1,t2
sw t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(enable_wdi)
/*************************************************************
* disable_wdi(ints)
* Disable the watchdog interrupt
*/
FRAME(disable_wdi,sp,0,ra)
.set noreorder
la t0,INT_CFG1 # Disable watchdog interrupt in USC320
lw t1,(t0)
li t2,~(WDI_MASK | MODE_TOTEM_POLE)
and t1,t1,t2
sw t1,(t0)
la t0,INT_STAT # Clear watchdog interrupt status bit
li t1,WDI_MASK
sw t1,(t0)
.set reorder
j ra
nop
.set reorder
ENDFRAME(disable_wdi)
