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Diffstat (limited to 'cpu/leon2/cpu_init.c')
-rw-r--r-- | cpu/leon2/cpu_init.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/cpu/leon2/cpu_init.c b/cpu/leon2/cpu_init.c new file mode 100644 index 0000000..a24f778 --- /dev/null +++ b/cpu/leon2/cpu_init.c @@ -0,0 +1,142 @@ +/* Initializes CPU and basic hardware such as memory + * controllers, IRQ controller and system timer 0. + * + * (C) Copyright 2007 + * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + */ + +#include <common.h> +#include <asm/asi.h> +#include <asm/leon.h> + +#include <config.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* reset CPU (jump to 0, without reset) */ +void start(void); + +struct { + gd_t gd_area; + bd_t bd; +} global_data; + +/* + * Breath some life into the CPU... + * + * Set up the memory map, + * initialize a bunch of registers. + * + * Run from FLASH/PROM: + * - until memory controller is set up, only registers avaiable + * - no global variables available for writing + * - constants avaiable + */ + +void cpu_init_f(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + + /* initialize the IRQMP */ + leon2->Interrupt_Force = 0; + leon2->Interrupt_Pending = 0; + leon2->Interrupt_Clear = 0xfffe; /* clear all old pending interrupts */ + leon2->Interrupt_Mask = 0xfffe0000; /* mask all IRQs */ + + /* cache */ + + /* I/O port setup */ +#ifdef LEON2_IO_PORT_DIR + leon2->PIO_Direction = LEON2_IO_PORT_DIR; +#endif +#ifdef LEON2_IO_PORT_DATA + leon2->PIO_Data = LEON2_IO_PORT_DATA; +#endif +#ifdef LEON2_IO_PORT_INT + leon2->PIO_Interrupt = LEON2_IO_PORT_INT; +#else + leon2->PIO_Interrupt = 0; +#endif +} + +void cpu_init_f2(void) +{ + +} + +/* + * initialize higher level parts of CPU like time base and timers + */ +int cpu_init_r(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + + /* initialize prescaler common to all timers to 1MHz */ + leon2->Scaler_Counter = leon2->Scaler_Reload = + (((CONFIG_SYS_CLK_FREQ / 1000) + 500) / 1000) - 1; + + return (0); +} + +/* Uses Timer 0 to get accurate + * pauses. Max 2 raised to 32 ticks + * + */ +void cpu_wait_ticks(unsigned long ticks) +{ + unsigned long start = get_timer(0); + while (get_timer(start) < ticks) ; +} + +/* initiate and setup timer0 interrupt to 1MHz + * Return irq number for timer int or a negative number for + * dealing with self + */ +int timer_interrupt_init_cpu(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + + /* 1ms ticks */ + leon2->Timer_Counter_1 = 0; + leon2->Timer_Reload_1 = 999; /* (((1000000 / 100) - 1)) */ + leon2->Timer_Control_1 = + (LEON2_TIMER_CTRL_EN | LEON2_TIMER_CTRL_RS | LEON2_TIMER_CTRL_LD); + + return LEON2_TIMER1_IRQNO; +} + +/* + * This function is intended for SHORT delays only. + */ +unsigned long cpu_usec2ticks(unsigned long usec) +{ + /* timer set to 1kHz ==> 1 clk tick = 1 msec */ + if (usec < 1000) + return 1; + return (usec / 1000); +} + +unsigned long cpu_ticks2usec(unsigned long ticks) +{ + /* 1tick = 1usec */ + return ticks * 1000; +} |