Enable mapping higher physical address
Current ATF uses a direct physical-to-virtual mapping, that is, a physical
address is mapped to the same address in the virtual space. For example,
physical address 0x8000_0000 is mapped to 0x8000_0000 virtual. This
approach works fine for FVP as all its physical addresses fall into 0 to
4GB range. But for other platform where all I/O addresses are 48-bit long,
If we follow the same direct mapping, we would need virtual address range
from 0 to 0x8fff_ffff_ffff, which is about 144TB. This requires a
significant amount of memory for MMU tables and it is not necessary to use
that much virtual space in ATF.
The patch is to enable mapping a physical address range to an arbitrary
virtual address range (instead of flat mapping)
Changed "base" to "base_va" and added "base_pa" in mmap_region_t and
modified functions such as mmap_add_region and init_xlation_table etc.
Fixes ARM-software/tf-issues#158
diff --git a/lib/aarch64/xlat_tables.c b/lib/aarch64/xlat_tables.c
index 29b81db..1b99cc8 100644
--- a/lib/aarch64/xlat_tables.c
+++ b/lib/aarch64/xlat_tables.c
@@ -72,26 +72,29 @@
debug_print("mmap:\n");
mmap_region_t *mm = mmap;
while (mm->size) {
- debug_print(" %010lx %10lx %x\n", mm->base, mm->size, mm->attr);
+ debug_print(" %010lx %010lx %10lx %x\n", mm->base_va,
+ mm->base_pa, mm->size, mm->attr);
++mm;
};
debug_print("\n");
#endif
}
-void mmap_add_region(unsigned long base, unsigned long size, unsigned attr)
+void mmap_add_region(unsigned long base_pa, unsigned long base_va,
+ unsigned long size, unsigned attr)
{
mmap_region_t *mm = mmap;
mmap_region_t *mm_last = mm + sizeof(mmap) / sizeof(mmap[0]) - 1;
- assert(IS_PAGE_ALIGNED(base));
+ assert(IS_PAGE_ALIGNED(base_pa));
+ assert(IS_PAGE_ALIGNED(base_va));
assert(IS_PAGE_ALIGNED(size));
if (!size)
return;
/* Find correct place in mmap to insert new region */
- while (mm->base < base && mm->size)
+ while (mm->base_va < base_va && mm->size)
++mm;
/* Make room for new region by moving other regions up by one place */
@@ -100,7 +103,8 @@
/* Check we haven't lost the empty sentinal from the end of the array */
assert(mm_last->size == 0);
- mm->base = base;
+ mm->base_pa = base_pa;
+ mm->base_va = base_va;
mm->size = size;
mm->attr = attr;
}
@@ -108,15 +112,15 @@
void mmap_add(const mmap_region_t *mm)
{
while (mm->size) {
- mmap_add_region(mm->base, mm->size, mm->attr);
+ mmap_add_region(mm->base_pa, mm->base_va, mm->size, mm->attr);
++mm;
}
}
-static unsigned long mmap_desc(unsigned attr, unsigned long addr,
+static unsigned long mmap_desc(unsigned attr, unsigned long addr_pa,
unsigned level)
{
- unsigned long desc = addr;
+ unsigned long desc = addr_pa;
desc |= level == 3 ? TABLE_DESC : BLOCK_DESC;
@@ -142,7 +146,7 @@
return desc;
}
-static int mmap_region_attr(mmap_region_t *mm, unsigned long base,
+static int mmap_region_attr(mmap_region_t *mm, unsigned long base_va,
unsigned long size)
{
int attr = mm->attr;
@@ -153,10 +157,10 @@
if (!mm->size)
return attr; /* Reached end of list */
- if (mm->base >= base + size)
+ if (mm->base_va >= base_va + size)
return attr; /* Next region is after area so end */
- if (mm->base + mm->size <= base)
+ if (mm->base_va + mm->size <= base_va)
continue; /* Next region has already been overtaken */
if ((mm->attr & attr) == attr)
@@ -164,12 +168,14 @@
attr &= mm->attr;
- if (mm->base > base || mm->base + mm->size < base + size)
+ if (mm->base_va > base_va ||
+ mm->base_va + mm->size < base_va + size)
return -1; /* Region doesn't fully cover our area */
}
}
-static mmap_region_t *init_xlation_table(mmap_region_t *mm, unsigned long base,
+static mmap_region_t *init_xlation_table(mmap_region_t *mm,
+ unsigned long base_va,
unsigned long *table, unsigned level)
{
unsigned level_size_shift = L1_XLAT_ADDRESS_SHIFT - (level - 1) *
@@ -184,23 +190,26 @@
do {
unsigned long desc = UNSET_DESC;
- if (mm->base + mm->size <= base) {
+ if (mm->base_va + mm->size <= base_va) {
/* Area now after the region so skip it */
++mm;
continue;
}
- debug_print(" %010lx %8lx " + 6 - 2 * level, base, level_size);
+ debug_print(" %010lx %8lx " + 6 - 2 * level, base_va,
+ level_size);
- if (mm->base >= base + level_size) {
+ if (mm->base_va >= base_va + level_size) {
/* Next region is after area so nothing to map yet */
desc = INVALID_DESC;
- } else if (mm->base <= base &&
- mm->base + mm->size >= base + level_size) {
+ } else if (mm->base_va <= base_va && mm->base_va + mm->size >=
+ base_va + level_size) {
/* Next region covers all of area */
- int attr = mmap_region_attr(mm, base, level_size);
+ int attr = mmap_region_attr(mm, base_va, level_size);
if (attr >= 0)
- desc = mmap_desc(attr, base, level);
+ desc = mmap_desc(attr,
+ base_va - mm->base_va + mm->base_pa,
+ level);
}
/* else Next region only partially covers area, so need */
@@ -211,14 +220,15 @@
desc = TABLE_DESC | (unsigned long)new_table;
/* Recurse to fill in new table */
- mm = init_xlation_table(mm, base, new_table, level+1);
+ mm = init_xlation_table(mm, base_va,
+ new_table, level+1);
}
debug_print("\n");
*table++ = desc;
- base += level_size;
- } while (mm->size && (base & level_index_mask));
+ base_va += level_size;
+ } while (mm->size && (base_va & level_index_mask));
return mm;
}