klipper/src/atsam/main.c

122 lines
3.1 KiB
C

// Main starting point for SAM3/SAM4 boards
//
// Copyright (C) 2016-2019 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "board/armcm_boot.h" // armcm_main
#include "board/irq.h" // irq_disable
#include "board/usb_cdc.h" // usb_request_bootloader
#include "command.h" // DECL_COMMAND_FLAGS
#include "internal.h" // WDT
#include "sched.h" // sched_main
/****************************************************************
* watchdog handler
****************************************************************/
void
watchdog_reset(void)
{
WDT->WDT_CR = 0xA5000001;
}
DECL_TASK(watchdog_reset);
void
watchdog_init(void)
{
uint32_t timeout = 500 * 32768 / 128 / 1000; // 500ms timeout
WDT->WDT_MR = WDT_MR_WDRSTEN | WDT_MR_WDV(timeout) | WDT_MR_WDD(timeout);
}
DECL_INIT(watchdog_init);
/****************************************************************
* Peripheral clocks
****************************************************************/
// Check if a peripheral clock has been enabled
int
is_enabled_pclock(uint32_t id)
{
if (id < 32)
return !!(PMC->PMC_PCSR0 & (1 << id));
else
return !!(PMC->PMC_PCSR1 & (1 << (id - 32)));
}
// Enable a peripheral clock
void
enable_pclock(uint32_t id)
{
if (id < 32)
PMC->PMC_PCER0 = 1 << id;
else
PMC->PMC_PCER1 = 1 << (id - 32);
}
/****************************************************************
* Resets
****************************************************************/
void
command_reset(uint32_t *args)
{
irq_disable();
RSTC->RSTC_CR = ((0xA5 << RSTC_CR_KEY_Pos) | RSTC_CR_PROCRST
| RSTC_CR_PERRST);
for (;;)
;
}
DECL_COMMAND_FLAGS(command_reset, HF_IN_SHUTDOWN, "reset");
#if CONFIG_MACH_SAM3X || CONFIG_MACH_SAM4S
#define EFC_HW EFC0
#elif CONFIG_MACH_SAM4E
#define EFC_HW EFC
#endif
void noinline __aligned(16) // align for predictable flash code access
usb_request_bootloader(void)
{
irq_disable();
// Request boot from ROM (instead of boot from flash)
while ((EFC_HW->EEFC_FSR & EEFC_FSR_FRDY) == 0)
;
EFC_HW->EEFC_FCR = (EEFC_FCR_FCMD_CGPB | EEFC_FCR_FARG(1)
| EEFC_FCR_FKEY_PASSWD);
while ((EFC_HW->EEFC_FSR & EEFC_FSR_FRDY) == 0)
;
// Reboot
RSTC->RSTC_CR = ((0xA5 << RSTC_CR_KEY_Pos) | RSTC_CR_PROCRST
| RSTC_CR_PERRST);
for (;;)
;
}
/****************************************************************
* Startup
****************************************************************/
static void
matrix_init(void)
{
// The ATSAM sram is in a "no default master" state at reset
// (despite the specs). That typically adds 1 wait cycle to every
// memory access. Set it to "last access master" to avoid that.
MATRIX->MATRIX_SCFG[0] = (MATRIX_SCFG_SLOT_CYCLE(64)
| MATRIX_SCFG_DEFMSTR_TYPE(1));
}
// Main entry point - called from armcm_boot.c:ResetHandler()
void
armcm_main(void)
{
SystemInit();
matrix_init();
sched_main();
}