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updated bootloader (minor edits)

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stnolting 2020-08-22 16:32:34 +02:00
parent d42b83b294
commit 4ef40de246
3 changed files with 1869 additions and 1032 deletions
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2856
rtl/core/neorv32_application_image.vhd
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File diff suppressed because it is too large Load diff

43
sw/bootloader/bootloader.c
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@ -64,7 +64,7 @@
#define BAUD_RATE (19200)
/** Time until the auto-boot sequence starts (in seconds) */
#define AUTOBOOT_TIMEOUT 8
/** Bootloader status LED at GPIO output port (0..15) */
/** Bootloader status LED at GPIO output port */
#define STATUS_LED (0)
/** SPI flash boot image base address */
#define SPI_FLASH_BOOT_ADR (0x00800000)
@ -141,7 +141,7 @@ enum NEORV32_EXECUTABLE {
// Function prototypes
void __attribute__((__interrupt__)) mtime_irq_handler(void);
void __attribute__((__interrupt__)) bootloader_trap_handler(void);
void print_help(void);
void start_app(void);
void get_exe(int src);
@ -188,10 +188,10 @@ int main(void) {
// Configure machine system timer interrupt for ~2Hz
neorv32_mtime_set_timecmp(neorv32_mtime_get_time() + (clock_speed/4));
// confiure interrupt vector (bare-metal, no neorv32 rte)
neorv32_cpu_csr_write(CSR_MTVEC, (uint32_t)(&mtime_irq_handler));
neorv32_cpu_csr_write(CSR_MIE, 1 << CPU_MIE_MTIE); // activate MTIME IRQ source
// confiure trap handler (bare-metal, no neorv32 rte available)
neorv32_cpu_csr_write(CSR_MTVEC, (uint32_t)(&bootloader_trap_handler));
neorv32_cpu_csr_write(CSR_MIE, 1 << CPU_MIE_MTIE); // activate MTIME IRQ source
neorv32_cpu_eint(); // enable global interrupts
// init GPIO
@ -229,11 +229,11 @@ int main(void) {
// ------------------------------------------------
// Auto boot sequence
// ------------------------------------------------
neorv32_uart_print("\n\nAutoboot in "xstr(AUTOBOOT_TIMEOUT)"s. Press key to abort.\n");
neorv32_uart_print("\n\nAutoboot in "xstr(AUTOBOOT_TIMEOUT)"s. Press any key to abort.\n");
uint64_t timeout_time = neorv32_mtime_get_time() + (uint64_t)(AUTOBOOT_TIMEOUT * clock_speed);
while ((UART_DATA & (1 << UART_DATA_AVAIL)) == 0) { // wait for any key to be pressed or timeout
while ((UART_DATA & (1 << UART_DATA_AVAIL)) == 0) { // wait for any key to be pressed
if (neorv32_mtime_get_time() >= timeout_time) { // timeout? start auto boot sequence
get_exe(EXE_STREAM_FLASH); // try loading from spi flash
@ -257,8 +257,7 @@ int main(void) {
if (c == 'r') { // restart bootloader
neorv32_cpu_dint(); // disable global interrupts
// jump to beginning of boot ROM
asm volatile ("li t0, %[input_i]; jr t0" : : [input_i] "i" (BOOTLOADER_BASE_ADDRESS));
asm volatile ("li t0, %[input_i]; jr t0" : : [input_i] "i" (BOOTLOADER_BASE_ADDRESS)); // jump to beginning of boot ROM
while(1); // just for the compiler
}
else if (c == 'h') { // help menu
@ -340,17 +339,18 @@ void start_app(void) {
/**********************************************************************//**
* Machine system timer (MTIME) interrupt handler.
* Bootloader trap handler.
* Primarily used for the MTIME tick.
* @warning Since we have no runtime environment, we have to use the interrupt attribute here. Here, and only here!
**************************************************************************/
void __attribute__((__interrupt__)) mtime_irq_handler(void) {
void __attribute__((__interrupt__)) bootloader_trap_handler(void) {
// make sure this was caused by MTIME IRQ
uint32_t cause = neorv32_cpu_csr_read(CSR_MCAUSE);
if (cause != TRAP_CODE_MTI) { // raw exception code for MTI
neorv32_uart_print("\n\nEXCEPTION: ");
neorv32_uart_print("\n\nEXCEPTION (");
print_hex_word(cause);
neorv32_uart_print(" @ 0x");
neorv32_uart_print(") @ 0x");
print_hex_word(neorv32_cpu_csr_read(CSR_MEPC));
system_error(ERROR_SYSTEM);
while(1); // freeze
@ -371,7 +371,7 @@ void __attribute__((__interrupt__)) mtime_irq_handler(void) {
**************************************************************************/
void get_exe(int src) {
// is instruction memory (actually, the IMEM) read-only?
// is instruction memory (IMEM) read-only?
if (SYSINFO_FEATURES & (1 << SYSINFO_FEATURES_MEM_INT_IMEM_ROM)) {
system_error(ERROR_ROM);
}
@ -420,19 +420,6 @@ void get_exe(int src) {
addr += 4;
}
/*
// Debugging stuff
neorv32_uart_putc('.');
print_hex_word(signature);
neorv32_uart_putc('.');
print_hex_word(imem_size);
neorv32_uart_putc('.');
print_hex_word(check);
neorv32_uart_putc('.');
print_hex_word(checksum);
neorv32_uart_putc('.');
*/
// error during transfer?
if ((checksum + check) != 0) {
system_error(ERROR_CHECKSUM);
@ -552,7 +539,7 @@ uint32_t get_exe_word(int src, uint32_t addr) {
**************************************************************************/
void system_error(uint8_t err_code) {
neorv32_uart_print("\a\nERR_"); // output error code with annoying bell sound
neorv32_uart_print("\a\nBootloader ERR_"); // output error code with annoying bell sound
if (err_code <= ERROR_SYSTEM) {
neorv32_uart_putc('0' + ((char)err_code));
}

2
sw/common/bootloader_neorv32.ld
View file

@ -53,7 +53,7 @@ SEARCH_DIR("=/opt/riscv/riscv64-unknown-linux-gnu/lib"); SEARCH_DIR("=/usr/local
/* ************************************************* */
MEMORY
{
bootrom (rx) : ORIGIN = 0xFFFF0000, LENGTH = 4*1024
bootrom (rx) : ORIGIN = 0xFFFF0000, LENGTH = 4*1024
}
/* ************************************************* */