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author | fishsoupisgood <github@madingley.org> | 2019-04-29 01:17:54 +0100 |
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committer | fishsoupisgood <github@madingley.org> | 2019-05-27 03:43:43 +0100 |
commit | 3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch) | |
tree | 65ca85f13617aee1dce474596800950f266a456c /roms/u-boot/arch/avr32/cpu/interrupts.c | |
download | qemu-master.tar.gz qemu-master.tar.bz2 qemu-master.zip |
Diffstat (limited to 'roms/u-boot/arch/avr32/cpu/interrupts.c')
-rw-r--r-- | roms/u-boot/arch/avr32/cpu/interrupts.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/roms/u-boot/arch/avr32/cpu/interrupts.c b/roms/u-boot/arch/avr32/cpu/interrupts.c new file mode 100644 index 00000000..4a03e19e --- /dev/null +++ b/roms/u-boot/arch/avr32/cpu/interrupts.c @@ -0,0 +1,112 @@ +/* + * Copyright (C) 2004-2006 Atmel Corporation + * + * SPDX-License-Identifier: GPL-2.0+ + */ +#include <common.h> +#include <div64.h> + +#include <asm/errno.h> +#include <asm/io.h> +#include <asm/processor.h> +#include <asm/sysreg.h> + +#include <asm/arch/hardware.h> + +#define HANDLER_MASK 0x00ffffff +#define INTLEV_SHIFT 30 +#define INTLEV_MASK 0x00000003 + +DECLARE_GLOBAL_DATA_PTR; + +/* Incremented whenever COUNT reaches 0xffffffff by timer_interrupt_handler */ +volatile unsigned long timer_overflow; + +/* + * Instead of dividing by get_tbclk(), multiply by this constant and + * right-shift the result by 32 bits. + */ +static unsigned long tb_factor; + +unsigned long get_tbclk(void) +{ + return gd->arch.cpu_hz; +} + +unsigned long long get_ticks(void) +{ + unsigned long lo, hi_now, hi_prev; + + do { + hi_prev = timer_overflow; + lo = sysreg_read(COUNT); + hi_now = timer_overflow; + } while (hi_prev != hi_now); + + return ((unsigned long long)hi_now << 32) | lo; +} + +unsigned long get_timer(unsigned long base) +{ + u64 now = get_ticks(); + + now *= tb_factor; + return (unsigned long)(now >> 32) - base; +} + +/* + * For short delays only. It will overflow after a few seconds. + */ +void __udelay(unsigned long usec) +{ + unsigned long cycles; + unsigned long base; + unsigned long now; + + base = sysreg_read(COUNT); + cycles = ((usec * (get_tbclk() / 10000)) + 50) / 100; + + do { + now = sysreg_read(COUNT); + } while ((now - base) < cycles); +} + +static int set_interrupt_handler(unsigned int nr, void (*handler)(void), + unsigned int priority) +{ + extern void _evba(void); + unsigned long intpr; + unsigned long handler_addr = (unsigned long)handler; + + handler_addr -= (unsigned long)&_evba; + + if ((handler_addr & HANDLER_MASK) != handler_addr + || (priority & INTLEV_MASK) != priority) + return -EINVAL; + + intpr = (handler_addr & HANDLER_MASK); + intpr |= (priority & INTLEV_MASK) << INTLEV_SHIFT; + writel(intpr, (void *)ATMEL_BASE_INTC + 4 * nr); + + return 0; +} + +int timer_init(void) +{ + extern void timer_interrupt_handler(void); + u64 tmp; + + sysreg_write(COUNT, 0); + + tmp = (u64)CONFIG_SYS_HZ << 32; + tmp += gd->arch.cpu_hz / 2; + do_div(tmp, gd->arch.cpu_hz); + tb_factor = (u32)tmp; + + if (set_interrupt_handler(0, &timer_interrupt_handler, 3)) + return -EINVAL; + + /* For all practical purposes, this gives us an overflow interrupt */ + sysreg_write(COMPARE, 0xffffffff); + return 0; +} |