initial commit of lk (little kernel) project
diff --git a/platform/integrator/debug.c b/platform/integrator/debug.c
new file mode 100644
index 0000000..ab9f901
--- /dev/null
+++ b/platform/integrator/debug.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <stdarg.h>
+#include <reg.h>
+#include <debug.h>
+#include <printf.h>
+#include <kernel/thread.h>
+#include <platform/debug.h>
+#include <arch/ops.h>
+#include <platform/integrator.h>
+
+static void write_uart_reg(int uart, int reg, unsigned char data)
+{
+ unsigned long base;
+ int mul = 4;
+
+ switch(uart) {
+ case 0: base = INTEGRATOR_UART0_REG_BASE; break;
+ case 1: base = INTEGRATOR_UART1_REG_BASE; break;
+ default: return;
+ }
+
+ *(volatile unsigned char *)(base + reg * mul) = data;
+}
+
+static unsigned char read_uart_reg(int uart, int reg)
+{
+ unsigned long base;
+ int mul = 4;
+
+ switch(uart) {
+ case 0: base = INTEGRATOR_UART0_REG_BASE; break;
+ case 1: base = INTEGRATOR_UART1_REG_BASE; break;
+ default: return 0;
+ }
+
+ return *(volatile unsigned char *)(base + reg * mul);
+}
+
+static int uart_init(void)
+{
+#if 0
+ /* clear the tx & rx fifo and disable */
+ write_uart_reg(0, UART_FCR, 0x6);
+#endif
+
+ return 0;
+}
+
+static int uart_putc(int port, char c )
+{
+ write_uart_reg(0, PL011_UARTDR, c);
+#if 0
+ while (!(read_uart_reg(port, UART_LSR) & (1<<6))) // wait for the shift register to empty
+ ;
+ write_uart_reg(port, UART_THR, c);
+#endif
+ return 0;
+}
+
+static int uart_getc(int port, bool wait) /* returns -1 if no data available */
+{
+#if 0
+ if (wait) {
+ while (!(read_uart_reg(port, UART_LSR) & (1<<0))) // wait for data to show up in the rx fifo
+ ;
+ } else {
+ if (!(read_uart_reg(port, UART_LSR) & (1<<0)))
+ return -1;
+ }
+ return read_uart_reg(port, UART_RHR);
+#endif
+ return -1;
+}
+
+void dputc(char c)
+{
+ uart_putc(0, c);
+}
+
+int dgetc(char *c)
+{
+ int result = uart_getc(0, false);
+
+ if (result < 0)
+ return -1;
+
+ *c = result;
+ return 0;
+}
+
+void debug_dump_regs(void)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+void debug_halt(void)
+{
+ dprintf("HALT: spinning forever...\n");
+ for(;;);
+}
+
+void debug_dump_memory_bytes(void *mem, int len)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+void debug_dump_memory_halfwords(void *mem, int len)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+void debug_dump_memory_words(void *mem, int len)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+void debug_set_trace_level(int trace_type, int level)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+uint32_t debug_cycle_count()
+{
+ PANIC_UNIMPLEMENTED;
+}
diff --git a/platform/integrator/include/platform/integrator.h b/platform/integrator/include/platform/integrator.h
new file mode 100644
index 0000000..47eaacb
--- /dev/null
+++ b/platform/integrator/include/platform/integrator.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef __INTEGRATOR_H
+#define __INTEGRATOR_H
+
+/* memory map */
+#define SDRAM_BASE 0x00000000
+
+#define INTEGRATOR_CORE_REG_BASE 0x10000000
+#define INTEGRATOR_SYS_REG_BASE 0x11000000
+#define INTEGRATOR_EBI_REG_BASE 0x12000000
+#define INTEGRATOR_TIMER_REG_BASE 0x13000000
+#define INTEGRATOR_INT_REG_BASE 0x14000000
+#define INTEGRATOR_UART0_REG_BASE 0x16000000
+#define INTEGRATOR_UART1_REG_BASE 0x17000000
+#define INTEGRATOR_LEDS_REG_BASE 0x1a000000
+#define INTEGRATOR_GPIO_REG_BASE 0x1b000000
+
+/* uart stuff */
+#define PL011_UARTDR (0)
+#define PL011_UARTRSR (1)
+#define PL011_UARTECR (1)
+#define PL011_UARTFR (6)
+#define PL011_UARTILPR (8)
+#define PL011_UARTIBRD (9)
+#define PL011_UARTFBRD (10)
+#define PL011_UARTLCR_H (11)
+#define PL011_UARTCR (12)
+#define PL011_UARTIFLS (13)
+#define PL011_UARTIMSC (14)
+#define PL011_UARTTRIS (15)
+#define PL011_UARTTMIS (16)
+#define PL011_UARTICR (17)
+#define PL011_UARTMACR (18)
+
+#define INT_VECTORS 32 // XXX just made this up
+
+#endif
+
diff --git a/platform/integrator/interrupts.c b/platform/integrator/interrupts.c
new file mode 100644
index 0000000..ef5f221
--- /dev/null
+++ b/platform/integrator/interrupts.c
@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <err.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <reg.h>
+#include <kernel/thread.h>
+#include <platform/interrupts.h>
+#include <arch/ops.h>
+#include <arch/arm.h>
+#include "platform_p.h"
+#include <platform/integrator.h>
+
+struct int_handler_struct {
+ int_handler handler;
+ void *arg;
+};
+
+static struct int_handler_struct int_handler_table[INT_VECTORS];
+
+#if 0
+static const uint32_t icBase[5] = {
+ INTCON0_BASE, INTCON1_BASE, INTCON2_BASE, INTCON3_BASE, INTCON4_BASE };
+
+/* a bitmap of the level triggered interrupt vectors */
+static uint32_t level_trigger[5] = {
+ 0xb3fefe8f, // level 1 0-31
+ 0xfdb3c1fd, // level 2 0-31
+ 0xfffff7ff, // level 2 32-63
+ 0xbfffffff, // level 2 64-95
+ 0xffffffff // level 2 96-128
+};
+
+inline volatile uint32_t *ICReg(uint controller, uint reg)
+{
+ return (volatile uint32_t *)(icBase[controller] + reg);
+}
+
+inline uint32_t readICReg(uint controller, uint reg)
+{
+ return *ICReg(controller, reg);
+}
+inline void writeICReg(uint controller, uint reg, uint val)
+{
+ *ICReg(controller, reg) = val;
+}
+
+inline uint vectorToController(uint vector)
+{
+ return vector / 32;
+}
+#endif
+
+void platform_init_interrupts(void)
+{
+#if 0
+ unsigned int i;
+
+ // mask all interrupts
+ *ICReg(0, INTCON_MIR) = 0xfffffffa;
+ *ICReg(1, INTCON_MIR) = 0xffffffff;
+ *ICReg(2, INTCON_MIR) = 0xffffffff;
+ *ICReg(3, INTCON_MIR) = 0xffffffff;
+ *ICReg(4, INTCON_MIR) = 0xffffffff;
+
+ // set up each of the interrupts
+ for (i = 0; i < INT_VECTORS; i++) {
+ // set each vector up as high priority, IRQ, and default edge/level sensitivity
+ *ICReg(i / 32, INTCON_ILR_BASE + 4*(i%32)) = ((level_trigger[i/32] & (1<<(i%32))) ? (1<<1) : (0<<1)) | 0;
+ }
+
+ // clear any pending interrupts
+ *ICReg(0, INTCON_ITR) = 0;
+ *ICReg(1, INTCON_ITR) = 0;
+ *ICReg(2, INTCON_ITR) = 0;
+ *ICReg(3, INTCON_ITR) = 0;
+ *ICReg(4, INTCON_ITR) = 0;
+
+ // globally unmask interrupts
+ *ICReg(1, INTCON_CONTROL) = 3;
+ *ICReg(0, INTCON_CONTROL) = 3;
+ *ICReg(0, INTCON_GMR) = 0;
+
+ dprintf("end of platform_init_interrupts\n");
+
+#if 0
+ arch_enable_ints();
+
+ dprintf("&ITR0 0x%x\n", (uint32_t)ICReg(0, INTCON_ITR));
+
+ dprintf("ITR0 0x%x\n", *ICReg(0, INTCON_ITR));
+ dprintf("MIR0 0x%x\n", *ICReg(0, INTCON_MIR));
+ dprintf("SIR_IRQ0 0x%x\n", *ICReg(0, INTCON_SIR_IRQ));
+
+ *ICReg(0, INTCON_ILR_BASE + 4*7) = 0;
+ *ICReg(0, INTCON_MIR) &= ~0x80;
+
+ dprintf("triggering int\n");
+
+ *ICReg(0, INTCON_SISR) = 0x80;
+
+ dprintf("ITR0 0x%x\n", *ICReg(0, INTCON_ITR));
+ dprintf("MIR0 0x%x\n", *ICReg(0, INTCON_MIR));
+ dprintf("SIR_IRQ0 0x%x\n", *ICReg(0, INTCON_SIR_IRQ));
+
+ for(;;);
+#endif
+#endif
+}
+
+status_t mask_interrupt(unsigned int vector, bool *oldstate)
+{
+#if 0
+ if (vector >= INT_VECTORS)
+ return ERR_INVALID_ARGS;
+
+// dprintf("%s: vector %d\n", __PRETTY_FUNCTION__, vector);
+
+ enter_critical_section();
+
+ if (oldstate)
+ *oldstate = false;
+
+ volatile uint32_t *mir = ICReg(vectorToController(vector), INTCON_MIR);
+ *mir = *mir | (1<<(vector % 32));
+
+ exit_critical_section();
+#endif
+
+ return NO_ERROR;
+}
+
+status_t unmask_interrupt(unsigned int vector, bool *oldstate)
+{
+#if 0
+ if (vector >= INT_VECTORS)
+ return ERR_INVALID_ARGS;
+
+// dprintf("%s: vector %d\n", __PRETTY_FUNCTION__, vector);
+
+ enter_critical_section();
+
+ if (oldstate)
+ *oldstate = false;
+
+ volatile uint32_t *mir = ICReg(vectorToController(vector), INTCON_MIR);
+ *mir = *mir & ~(1<<(vector % 32));
+
+ exit_critical_section();
+#endif
+
+ return NO_ERROR;
+}
+
+void platform_irq(struct arm_iframe *frame)
+{
+ PANIC_UNIMPLEMENTED;
+#if 0
+ // get the current vector
+ unsigned int vector;
+
+ inc_critical_section();
+
+ // read from the first level int handler
+ vector = *ICReg(0, INTCON_SIR_IRQ);
+
+ // see if it's coming from the second level handler
+ if (vector == 0) {
+ vector = *ICReg(1, INTCON_SIR_IRQ) + 32;
+ }
+
+// dprintf("platform_irq: spsr 0x%x, pc 0x%x, currthread %p, vector %d\n", frame->spsr, frame->pc, current_thread, vector);
+
+ // deliver the interrupt
+ enum handler_return ret;
+
+ ret = INT_NO_RESCHEDULE;
+ if (int_handler_table[vector].handler)
+ ret = int_handler_table[vector].handler(int_handler_table[vector].arg);
+
+ // ack the interrupt
+ if (vector >= 32) {
+ // interrupt is chained, so ack the second level first, and then the first
+ *ICReg(vector / 32, INTCON_ITR) = ~(1 << (vector % 32));
+ *ICReg(1, INTCON_CONTROL) |= 1;
+ vector = 0; // force the following code to ack the chained first level vector
+ }
+
+ *ICReg(0, INTCON_ITR) = ~(1 << vector);
+ *ICReg(0, INTCON_CONTROL) = 1;
+
+ if (ret == INT_RESCHEDULE)
+ thread_preempt();
+
+ dec_critical_section();
+
+// dprintf("platform_irq: exit\n");
+#endif
+}
+
+void platform_fiq(struct arm_iframe *frame)
+{
+ PANIC_UNIMPLEMENTED;
+}
+
+void register_int_handler(unsigned int vector, int_handler handler, void *arg)
+{
+ if (vector >= INT_VECTORS)
+ panic("register_int_handler: vector out of range %d\n", vector);
+
+ enter_critical_section();
+
+ int_handler_table[vector].handler = handler;
+ int_handler_table[vector].arg = arg;
+
+ exit_critical_section();
+}
+
diff --git a/platform/integrator/platform.c b/platform/integrator/platform.c
new file mode 100644
index 0000000..5b31242
--- /dev/null
+++ b/platform/integrator/platform.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <err.h>
+#include <debug.h>
+#include <platform.h>
+#include "platform_p.h"
+#include <platform/integrator.h>
+#include <arch/arm/mmu.h>
+
+void platform_init_mmu_mappings(void)
+{
+}
+
+void platform_early_init(void)
+{
+#if 0
+ /* do some memory map initialization */
+ addr_t addr;
+ arm_mmu_map_section(SDRAM_BASE, 0, MMU_FLAG_CACHED|MMU_FLAG_BUFFERED);
+ for (addr = SDRAM_BASE; addr < SDRAM_BASE + SDRAM_SIZE; addr += (1024*1024)) {
+ arm_mmu_map_section(addr, addr, MMU_FLAG_CACHED|MMU_FLAG_BUFFERED|MMU_FLAG_READWRITE);
+ }
+
+ /* initialize the interrupt controller */
+ platform_init_interrupts();
+
+ /* initialize the timer block */
+ platform_init_timer();
+#endif
+}
+
+void platform_init(void)
+{
+}
+
diff --git a/platform/integrator/platform_p.h b/platform/integrator/platform_p.h
new file mode 100644
index 0000000..872ea2b
--- /dev/null
+++ b/platform/integrator/platform_p.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef __PLATFORM_P_H
+#define __PLATFORM_P_H
+
+void platform_init_interrupts(void);
+void platform_init_timer(void);
+
+#endif
+
diff --git a/platform/integrator/rules.mk b/platform/integrator/rules.mk
new file mode 100644
index 0000000..a189153
--- /dev/null
+++ b/platform/integrator/rules.mk
@@ -0,0 +1,26 @@
+LOCAL_DIR := $(GET_LOCAL_DIR)
+
+ARCH := arm
+ARM_CPU := arm926ej-s
+CPU := generic
+
+INCLUDES += \
+ -I$(LOCAL_DIR)/include
+
+OBJS += \
+ $(LOCAL_DIR)/debug.o \
+ $(LOCAL_DIR)/platform.o \
+ $(LOCAL_DIR)/interrupts.o \
+ $(LOCAL_DIR)/timer.o \
+
+# $(LOCAL_DIR)/net.o \
+
+
+# $(LOCAL_DIR)/console.o \
+
+MEMBASE ?= 0x0
+MEMSIZE ?= 0x08000000 # 128MB
+
+LINKER_SCRIPT += \
+ $(BUILDDIR)/system-onesegment.ld
+
diff --git a/platform/integrator/timer.c b/platform/integrator/timer.c
new file mode 100644
index 0000000..55d14de
--- /dev/null
+++ b/platform/integrator/timer.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (c) 2008 Travis Geiselbrecht
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files
+ * (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge,
+ * publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+ * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <sys/types.h>
+#include <err.h>
+#include <kernel/thread.h>
+#include <debug.h>
+#include <platform.h>
+#include <platform/interrupts.h>
+#include <platform/timer.h>
+#include <platform/integrator.h>
+#include "platform_p.h"
+
+static time_t system_time = 0;
+
+static time_t tick_interval;
+static uint32_t ticks_per_interval;
+static platform_timer_callback t_callback;
+static void *callback_arg;
+
+status_t platform_set_periodic_timer(platform_timer_callback callback, void *arg, time_t interval)
+{
+#if 0
+ enter_critical_section();
+
+ t_callback = callback;
+ callback_arg = arg;
+ tick_interval = interval;
+ ticks_per_interval = interval * 32768 / 1000; // interval is in ms
+
+ OS_TIMER_CTRL_REG = 0; // stop it
+ OS_TIMER_TICK_VALUE_REG = ticks_per_interval;
+ OS_TIMER_CTRL_REG = (1<<3) | (1<<2) | (1<<1) | (1<<0);
+
+ exit_critical_section();
+#endif
+
+ return NO_ERROR;
+}
+
+time_t current_time(void)
+{
+#if 0
+ time_t t;
+ uint32_t delta_ticks;
+ uint32_t delta_ticks2;
+
+retry:
+ delta_ticks = OS_TIMER_TICK_COUNTER_REG;
+ t = system_time;
+ delta_ticks2 = OS_TIMER_TICK_COUNTER_REG;
+ if (delta_ticks2 > delta_ticks)
+ goto retry;
+
+ t += ((ticks_per_interval - delta_ticks2) * tick_interval) / ticks_per_interval;
+
+ return t;
+#else
+ static time_t time = 0;
+ return time++;
+#endif
+
+}
+
+static enum handler_return os_timer_tick(void *arg)
+{
+ system_time += tick_interval;
+// dprintf("os_timer_tick %d\n", system_time);
+
+ return t_callback(callback_arg, system_time);
+}
+
+void platform_init_timer(void)
+{
+#if 0
+ OS_TIMER_CTRL_REG = 0; // stop the timer if it's already running
+
+ register_int_handler(IRQ_OS_TIMER, &os_timer_tick, NULL);
+ unmask_interrupt(IRQ_OS_TIMER, NULL);
+#endif
+}
+