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#include "uart.h"
#include "io.h"
#include "demo_functionality.h"
#include "paging.h"
#include "atags.h"
// for POWER_OF_2() macro... perhaps the macro should be moved
#include "memory.h"
#include "armclock.h"
#include "scheduler.h"
void setup(uint32_t r0, uint32_t machine_type,
struct atag_header *atags)
{
uart_init();
// When we attach screen session after loading kernel with socat
// we miss kernel's greeting... So we'll make the kernel wait for
// one char we're going to send from within screen
getchar();
puts("Hello, kernel World!");
prints("ARM machine type: 0x"); printhext(machine_type); puts("");
uint32_t memory_size = 0;
// value 3 introduced by stage1 code means no atags was found
if (r0 == 3)
{
puts ("No ATAGS was found!");
}
else
{
prints("ATAGS copied to 0x");
printhex((uint32_t) atags); puts("");
puts("__ ATAGS contents __");
print_atags(atags);
puts("__ end of ATAGS contents __");
memory_size = find_memory_size(atags);
}
if (memory_size)
{
char *unit;
uint32_t size_in_unit;
if (memory_size % POWER_OF_2(10))
{
unit = "B";
size_in_unit = memory_size;
}
else if (memory_size % POWER_OF_2(20))
{
unit = "KB";
size_in_unit = memory_size / POWER_OF_2(10);
}
else if (memory_size % POWER_OF_2(30))
{
unit = "MB";
size_in_unit = memory_size / POWER_OF_2(20);
}
else
{
unit = "GB";
size_in_unit = memory_size / POWER_OF_2(30);
}
prints ("memory available: ");
printdect (size_in_unit);
puts (unit);
}
else
{
// Most Pis have more, but qemu might give us little
puts("Couldn't determine available memory - assuming 192MB");
memory_size = 192 * POWER_OF_2(20);
}
// assume we need at least one section for PL0
if (memory_size < PRIVILEGED_MEMORY_END + SECTION_SIZE)
{
puts("Not enough memory to continue");
while (1);
}
// prints some info
demo_paging_support();
// prints some info
demo_current_mode();
setup_pager_structures(memory_size);
// prints some info and sets upp translation table, turns on MMU
setup_flat_map();
puts("Initializing clock");
// sets some general settings for arm timer
armclk_init();
puts("Setting up scheduler's internal structures");
setup_scheduler_structures();
puts("Switching uart to use irqs");
// note, that kernel's puts() is still going to use blocking io
uart_irq_enable();
// prints some info and sets up a section for PL0 code, loads a blob
// there, then runs scheduler... never, ever, ever returns
demo_setup_PL0();
}
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