/**
* @file
*
* @ingroup RTEMSBSPsARMCycV
*/
/*
* Copyright (c) 2017 embedded brains GmbH
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <bsp/bootcard.h>
#include <bsp/arm-cp15-start.h>
#include <bsp/fdt.h>
#include <bsp/linker-symbols.h>
#include <libcpu/arm-cp15.h>
#include <libfdt.h>
#ifdef BSP_FDT_IS_SUPPORTED
#define AREA_COUNT_MAX 16
static const char memory_path[] = "/memory";
static const char reserved_memory_path[] = "/reserved-memory";
static void adjust_memory_size(const void *fdt, Heap_Area *area)
{
int node;
node = fdt_path_offset_namelen(
fdt,
memory_path,
(int) sizeof(memory_path) - 1
);
if (node >= 0) {
int len;
const void *val;
uintptr_t begin;
uintptr_t size;
uintptr_t a_bit;
val = fdt_getprop(fdt, node, "reg", &len);
if (len == 8) {
begin = fdt32_to_cpu(((fdt32_t *) val)[0]);
size = fdt32_to_cpu(((fdt32_t *) val)[1]);
} else {
begin = 0;
size = 0;
}
/*
* Remove a bit to avoid problems with speculative memory accesses beyond
* the valid memory area.
*/
a_bit = 0x100000;
if (size >= a_bit) {
size -= a_bit;
}
if (
begin == 0
&& size > (uintptr_t) bsp_section_work_end
&& (uintptr_t) bsp_section_nocache_end
< (uintptr_t) bsp_section_work_end
) {
area->size += size - (uintptr_t) bsp_section_work_end;
}
}
}
static Heap_Area *find_area(
Heap_Area *areas,
size_t area_count,
uint32_t begin
)
{
size_t i;
for (i = 0; i < area_count; ++i) {
uintptr_t b;
uintptr_t e;
b = (uintptr_t) areas[i].begin;
e = b + (uintptr_t) areas[i].size;
if (b <= begin && begin < e) {
return &areas[i];
}
}
return NULL;
}
static size_t remove_reserved_memory(
const void *fdt,
Heap_Area *areas,
size_t area_count
)
{
int node;
node = fdt_path_offset_namelen(
fdt,
reserved_memory_path,
(int) sizeof(reserved_memory_path) - 1
);
if (node >= 0) {
node = fdt_first_subnode(fdt, node);
while (node >= 0) {
int len;
const void *val;
uintptr_t area_begin;
uintptr_t area_end;
uintptr_t hole_begin;
uintptr_t hole_end;
Heap_Area *area;
val = fdt_getprop(fdt, node, "reg", &len);
if (len == 8) {
hole_begin = fdt32_to_cpu(((fdt32_t *) val)[0]);
hole_end = hole_begin + fdt32_to_cpu(((fdt32_t *) val)[1]);
} else {
rtems_panic("unexpected reserved memory area");
}
area = find_area(areas, area_count, hole_begin);
area_begin = (uintptr_t) area->begin;
area_end = area_begin + (uintptr_t) area->size;
area->size = hole_begin - area_begin;
if (hole_end <= area_end) {
if (area_count >= AREA_COUNT_MAX) {
rtems_panic("too many reserved memory areas");
}
area = &areas[area_count];
++area_count;
area->begin = (void *) hole_end;
area->size = area_end - hole_end;
}
node = fdt_next_subnode(fdt, node);
}
}
return area_count;
}
#else /* !BSP_FDT_IS_SUPPORTED */
#define AREA_COUNT_MAX 1
#endif /* BSP_FDT_IS_SUPPORTED */
void bsp_work_area_initialize(void)
{
Heap_Area areas[AREA_COUNT_MAX];
size_t area_count;
#ifdef BSP_FDT_IS_SUPPORTED
const void *fdt;
size_t i;
#endif
areas[0].begin = bsp_section_work_begin;
areas[0].size = (uintptr_t) bsp_section_work_size;
area_count = 1;
#ifdef BSP_FDT_IS_SUPPORTED
fdt = bsp_fdt_get();
adjust_memory_size(fdt, &areas[0]);
area_count = remove_reserved_memory(fdt, areas, area_count);
for (i = 0; i < area_count; ++i) {
arm_cp15_set_translation_table_entries(
areas[i].begin,
(void *) ((uintptr_t) areas[i].begin + areas[i].size),
ARMV7_MMU_READ_WRITE_CACHED
);
}
#endif
bsp_work_area_initialize_with_table(areas, area_count);
}