/*
* ATTENTION: As MC68349 has no built-in Timer, the following code doesn't work
* in a MC68349. You can't use FIFO full mode for the moment, but
* it should be easy to fix this by using an external timer.
*
* Use TIMER 1 for TIMEOUT when using FIFO FULL mode in UART driver
* Use TIMER 2 for timing test suites
*
* NOTE: It is important that the timer start/stop overhead be
* determined when porting or modifying this code.
*/
/*
* Geoffroy Montel
* France Telecom - CNET/DSM/TAM/CAT
* 4, rue du Clos Courtel
* 35512 CESSON-SEVIGNE
* FRANCE
*
* e-mail: g_montel@yahoo.com
*
* COPYRIGHT (c) 1989-1999.
* 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 <rtems.h>
#include <bsp.h>
#include <rtems/btimer.h>
#include <m340uart.h>
#include <m340timer.h>
#include <m68340.h>
#define TIMER1_VECTOR 122
#define TIMER1_IRQ_LEVEL 5
#define TIMER1_INTERRUPT_ARBITRATION 5
#define TIMER2_VECTOR 123
#define TIMER2_IRQ_LEVEL 4
#define TIMER2_INTERRUPT_ARBITRATION 4
#define CLOCK_SPEED 25 /* in Mhz */
#define max(a,b) (((a)>(b)) ? (a) : (b))
void (*Restart_Fifo_Full_A_Timer)(void);
void (*Restart_Check_A_Timer)(void);
void (*Restart_Fifo_Full_B_Timer)(void);
void (*Restart_Check_B_Timer)(void);
int preload = 0;
/*
* __Restart_Fifo_Full_Timer
*
* When a character is received, sets the TIMER to raise an interrupt at
* TIMEOUT. It's necessary to prevent from not getting n-1 characters
* (with n the Uart Fifo size).
*/
static void __Restart_Fifo_Full_Timer (void)
{
TSR1 |= m340_TO;
TCR1 &= ~m340_CPE;
WPREL11 = preload;
TCR1 |= m340_CPE;
}
/*
* __Restart_Check_Timer
*
* When no character has been received recently, check now and then if whether
* a there's a character in the FIFO
*/
static void __Restart_Check_Timer (void)
{
TSR1 |= m340_TO;
TCR1 &= ~m340_CPE;
WPREL11 = 0xFFFF;
TCR1 |= m340_CPE;
}
/*
* __do_nothing
*
* We always restart the fifo full timer with a call to Restart_*_Timer
* if we do not use FIFO full, Restart_X_Timer are set to do __do_nothing
*/
static void __do_nothing (void)
{
}
#define Fifo_Full_on_A \
(m340_uart_config[UART_CHANNEL_A].rx_mode==UART_FIFO_FULL && \
m340_uart_config[UART_CHANNEL_A].enable && \
m340_uart_config[UART_CHANNEL_A].mode==UART_INTERRUPTS)
#define Fifo_Full_on_B \
(m340_uart_config[UART_CHANNEL_B].rx_mode==UART_FIFO_FULL && \
m340_uart_config[UART_CHANNEL_B].enable && \
m340_uart_config[UART_CHANNEL_B].mode==UART_INTERRUPTS)
/*
* Fifo_Full_benchmark_timer_initialize
*
* initialize Timer 1 for FIFO full mode
*/
void Fifo_Full_benchmark_timer_initialize (void)
{
float max_baud_rate;
int prescaler_output_tap = -1;
int nb_of_clock_ticks = 0;
rtems_isr_entry old_handler;
/*
* USE TIMER 1 for UART FIFO FULL mode
*/
if ( Fifo_Full_on_A || Fifo_Full_on_B ) {
/* Disable the timer */
TCR1 &= ~m340_SWR;
/* Reset the interrupts */
TSR1 &= ~(m340_TO | m340_TG | m340_TC);
/* Init the stop bit for normal operation, ignore FREEZE, user privileges,
* set interrupt arbitration.
*/
TMCR1 = TIMER1_INTERRUPT_ARBITRATION;
/* interrupt priority level and interrupt vector */
TIR1 = TIMER1_VECTOR | (TIMER1_IRQ_LEVEL << 8);
/* compute prescaler */
if ( Fifo_Full_on_A && Fifo_Full_on_B) {
max_baud_rate = max(
m340_uart_config[UART_CHANNEL_A].rx_baudrate,
m340_uart_config[UART_CHANNEL_B].rx_baudrate
);
} else if ( Fifo_Full_on_A ) {
max_baud_rate = m340_uart_config[UART_CHANNEL_A].rx_baudrate;
} else
max_baud_rate = m340_uart_config[UART_CHANNEL_B].rx_baudrate;
/* find out config */
nb_of_clock_ticks = (10/max_baud_rate)*(CLOCK_SPEED*1000000)*1.2;
if (nb_of_clock_ticks < 0xFFFF) {
preload = nb_of_clock_ticks;
prescaler_output_tap = -1;
} else if (nb_of_clock_ticks/2 < 0xFFFF) {
preload = nb_of_clock_ticks/2;
prescaler_output_tap = m340_Divide_by_2;
} else if (nb_of_clock_ticks/4 < 0xFFFF) {
preload = nb_of_clock_ticks/4;
prescaler_output_tap = m340_Divide_by_4;
} else if (nb_of_clock_ticks/8 < 0xFFFF) {
preload = nb_of_clock_ticks/8;
prescaler_output_tap = m340_Divide_by_16;
} else if (nb_of_clock_ticks/16 < 0xFFFF) {
preload = nb_of_clock_ticks/16;
prescaler_output_tap = m340_Divide_by_16;
} else if (nb_of_clock_ticks/32 < 0xFFFF) {
preload = nb_of_clock_ticks/32;
prescaler_output_tap = m340_Divide_by_32;
} else if (nb_of_clock_ticks/64 < 0xFFFF) {
preload = nb_of_clock_ticks/64;
prescaler_output_tap = m340_Divide_by_64;
} else if (nb_of_clock_ticks/128 < 0xFFFF) {
preload = nb_of_clock_ticks/128;
prescaler_output_tap = m340_Divide_by_128;
} else if (nb_of_clock_ticks/256 < 0xFFFF) {
preload = nb_of_clock_ticks/256;
prescaler_output_tap = m340_Divide_by_256;
}
/* Input Capture/Output Compare (ICOC) */
TCR1 = m340_SWR | m340_TO_Enabled | m340_ICOC;
if (prescaler_output_tap!=-1) TCR1 |= prescaler_output_tap | m340_PSE;
/* install interrupt vector */
rtems_interrupt_catch(InterruptHandler, TIMER1_VECTOR, &old_handler);
} /* fifo full mode on a uart */
/* install routines */
if ( Fifo_Full_on_A ) {
Restart_Check_A_Timer = __Restart_Check_Timer;
Restart_Fifo_Full_A_Timer = __Restart_Fifo_Full_Timer;
} else {
Restart_Check_A_Timer = __do_nothing;
Restart_Fifo_Full_A_Timer = __do_nothing;
}
if ( Fifo_Full_on_B ) {
Restart_Check_B_Timer = __Restart_Check_Timer;
Restart_Fifo_Full_B_Timer = __Restart_Fifo_Full_Timer;
} else {
Restart_Check_B_Timer = __do_nothing;
Restart_Fifo_Full_B_Timer = __do_nothing;
}
/* start checking timer */
Restart_Check_A_Timer();
Restart_Check_B_Timer();
}
/*
* benchmark_timer_initialize
*
* init Timer for timing test suites
*/
void benchmark_timer_initialize (void)
{
/* Disable the timer */
TCR2 &= ~m340_SWR;
/* Reset the interrupts */
TSR2 &= ~(m340_TO | m340_TG | m340_TC);
/* Init the stop bit for normal operation, ignore FREEZE, user privileges,
set interrupt arbitration */
TMCR1 = TIMER2_INTERRUPT_ARBITRATION;
/* interrupt priority level and interrupt vector */
TIR1 = TIMER2_VECTOR | (TIMER2_IRQ_LEVEL << 8);
/* Init the stop bit for normal operation, ignore FREEZE, user privileges,
set interrupt arbitration */
TMCR2 = TIMER2_INTERRUPT_ARBITRATION;
/* Preload register 1 */
WPREL21 = 0xFFFF;
/* Input Capture/Output Compare (ICOC) */
TCR2 = m340_SWR | m340_ICOC | m340_PSE | m340_Divide_by_16 | m340_CPE;
}
/*
* benchmark_timer_read
*
* Return timer value in microsecond units
*/
uint32_t benchmark_timer_read (void)
{
/* there's CLOCK_SPEED / 16 micro seconds between two timer
* register decrements.
*/
return (((0xFFFF - TCNTR2) * CLOCK_SPEED) / 16);
}
/*
* benchmark_timer_disable_subtracting_average_overhead
*/
void benchmark_timer_disable_subtracting_average_overhead(bool find_flag)
{
}
