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#include <apos/init.h>
#include <apos/sizes.h>
#include <apos/types.h>
#include <apos/string.h>
#include <apos/debug.h>
#include <apos/pmem.h>
#include <apos/utils.h>
#include <libfdt.h>
#include <pages.h>
#include <csr.h>
#include <vmap.h>
struct mem_layout {
pm_t base;
pm_t top;
};
struct cell_info {
uint32_t size_cells;
uint32_t addr_cells;
};
static struct cell_info get_cellinfo(void *fdt, int offset)
{
struct cell_info ret = {
fdt_size_cells(fdt, offset),
fdt_address_cells(fdt, offset)
};
return ret;
}
static struct mem_layout get_memlayout(void *fdt)
{
struct cell_info ci = get_cellinfo(fdt, 0);
int mem_offset = fdt_path_offset(fdt, "/memory");
uint8_t *mem_reg =
(uint8_t *) fdt_getprop(fdt, mem_offset, "reg", NULL);
pm_t base;
/* if riscv128 comes around we will probably see addr_cells == 4, but
* I'm not too concerned about it at the moment */
if (ci.addr_cells == 2) {
base = fdt64_to_cpu(*(fdt64_t *) mem_reg);
mem_reg += sizeof(fdt64_t);
} else {
base = fdt32_to_cpu(*(fdt32_t *) mem_reg);
mem_reg += sizeof(fdt32_t);
}
pm_t top;
if (ci.size_cells == 2)
top = fdt64_to_cpu(*(fdt64_t *) mem_reg) + base;
else
top = fdt32_to_cpu(*(fdt64_t *) mem_reg) + base;
struct mem_layout ret = { base, top };
return ret;
}
#ifdef DEBUG
/* this should probably be improved in the future, possibly also moved
* somewhere? */
static enum serial_dev_t serial_dev_enum(const char *dev_name)
{
if (strncmp("ns16550", dev_name, 7) == 0)
return NS16550A;
return -1;
}
static void init_debug(void *fdt)
{
int chosen_offset = fdt_path_offset(fdt, "/chosen");
const char *stdout = fdt_getprop(fdt, chosen_offset, "stdout-path", 0);
int stdout_offset = fdt_path_offset(fdt, stdout);
/* get serial device type */
const char *dev_name = (const char *)fdt_getprop(fdt, stdout_offset,
"compatible", NULL);
enum serial_dev_t dev = serial_dev_enum(dev_name);
/* get serial device address */
struct cell_info ci = get_cellinfo(fdt, stdout_offset);
void *reg_ptr = (void *)fdt_getprop(fdt, stdout_offset, "reg", NULL);
void *uart_ptr = 0;
if (ci.addr_cells == 2)
uart_ptr = (void *)(pm_t)fdt64_to_cpu(*(fdt64_t *) reg_ptr);
else
uart_ptr = (void *)(pm_t)fdt32_to_cpu(*(fdt32_t *) reg_ptr);
dbg_init(uart_ptr, dev);
}
#else
#define init_debug(...)
#endif
/* TODO: these */
static pm_t get_kerneltop(void *fdt)
{
return 0;
}
static pm_t get_initrdtop(void *fdt)
{
return 0;
}
static pm_t get_fdttop(void *fdt)
{
return 0;
}
static void setup_pmem(void *fdt)
{
struct mem_layout pmem = get_memlayout(fdt);
pm_t kernel_top = get_kerneltop(fdt);
pm_t initrd_top = get_initrdtop(fdt);
pm_t fdt_top = get_fdttop(fdt);
pm_t top = MAX3(kernel_top, initrd_top, fdt_top);
}
void __noreturn init(void *fdt)
{
init_debug(fdt);
dbg_fdt(fdt);
setup_pmem(fdt);
/* basic memory layout info */
struct mem_layout pmem = get_memlayout(fdt);
/* TODO: find first contiguous region */
/* generate pagetable at contiguous region */
populate_pmap(pmem.base, pmem.top - pmem.base, 0/* something */);
/* TODO: mark all used pages */
update_pmap(0/* TODO: figure out where in virtual memory the page map should be mapped */);
/* TODO: jump to kernel */
}
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