Page MenuHomeFreeBSD
Files F163246898

D54716.id.diff
No OneTemporary
Actions

D54716.id.diff
View Options

diff --git a/sys/riscv/riscv/pmap.c b/sys/riscv/riscv/pmap.c
--- a/sys/riscv/riscv/pmap.c
+++ b/sys/riscv/riscv/pmap.c
@@ -578,16 +578,13 @@
}
/*
- * Construct the direct map -- a linear mapping of physical memory into
+ * Construct the Direct Map -- a linear mapping of physical memory into
* the kernel address space.
*
* We walk the list of physical memory segments (of arbitrary size and
- * address) mapping each appropriately using L2 and L1 superpages.
- * Consequently, the DMAP address space will have unmapped regions
- * corresponding to any holes between physical memory segments.
- *
- * The lowest usable physical address will always be mapped to
- * DMAP_MIN_ADDRESS.
+ * alignment) mapping each appropriately. Consequently, the DMAP address
+ * space will have unmapped regions corresponding to the holes between
+ * physical memory segments.
*/
static vm_paddr_t
pmap_bootstrap_dmap(pd_entry_t *l1, vm_paddr_t freemempos)
@@ -595,9 +592,9 @@
vm_paddr_t physmap[PHYS_AVAIL_ENTRIES];
vm_offset_t va;
vm_paddr_t min_pa, max_pa, pa, endpa;
- pd_entry_t *l2;
+ pd_entry_t *l3, *l2;
pt_entry_t memattr;
- u_int l1slot, l2slot;
+ u_int l1slot, l2slot, l3slot;
int physmap_idx;
physmap_idx = physmem_avail(physmap, nitems(physmap));
@@ -614,17 +611,58 @@
memattr = pmap_memattr_bits(VM_MEMATTR_DEFAULT);
- /* Walk the physmap table. */
- l2 = NULL;
- l1slot = Ln_ENTRIES; /* sentinel value */
+ /*
+ * Walk the physmap table, using the largest page sizes possible for each
+ * mapping. So, for each physmap entry, map as needed/able:
+ * - 4K/L3 page prefix
+ * - 2M/L2 superpage prefix
+ * - 1G/L1 superpages
+ * - 2M/L2 superpage suffix
+ * - 4K/L3 page suffix
+ */
+ l3 = l2 = NULL;
+ l2slot = l1slot = Ln_ENTRIES; /* sentinel value */
for (int idx = 0; idx < physmap_idx; idx += 2) {
- pa = rounddown(physmap[idx], L2_SIZE);
+ pa = rounddown(physmap[idx], L3_SIZE);
endpa = physmap[idx + 1];
/* Virtual address for this range. */
va = PHYS_TO_DMAP(pa);
- /* Any 1GB possible for this range? */
+ /* Any 2MB possible for this range? */
+ if (roundup(pa, L2_SIZE) + L2_SIZE > endpa)
+ goto l3end;
+
+ /* Loop until the next 2MB boundary. */
+ while ((pa & L2_OFFSET) != 0) {
+ if (l2 == NULL || pmap_l1_index(va) != l1slot) {
+ /* Need to alloc another page table. */
+ l2 = pmap_early_alloc_tables(&freemempos, 1);
+
+ /* Link it. */
+ l1slot = pmap_l1_index(va);
+ pmap_store(&l1[l1slot],
+ L1_PDE((vm_paddr_t)l2, PTE_V));
+ }
+
+ if (l3 == NULL || pmap_l2_index(va) != l2slot) {
+ l3 = pmap_early_alloc_tables(&freemempos, 1);
+
+ /* Link it to L2. */
+ l2slot = pmap_l2_index(va);
+ pmap_store(&l2[l2slot],
+ L2_PDE((vm_paddr_t)l3, PTE_V));
+ }
+
+ /* map l3 pages */
+ l3slot = pmap_l3_index(va);
+ pmap_store(&l3[l3slot], L3_PTE(pa, PTE_KERN | memattr));
+
+ pa += L3_SIZE;
+ va += L3_SIZE;
+ }
+
+ /* Any 1GB possible for remaining range? */
if (roundup(pa, L1_SIZE) + L1_SIZE > endpa)
goto l2end;
@@ -659,7 +697,8 @@
}
l2end:
- while (pa < endpa) {
+ /* Map what we can with 2MB superpages. */
+ while (pa + L2_SIZE - 1 < endpa) {
if (l2 == NULL || pmap_l1_index(va) != l1slot) {
/* Need to alloc another page table. */
l2 = pmap_early_alloc_tables(&freemempos, 1);
@@ -677,6 +716,35 @@
pa += L2_SIZE;
va += L2_SIZE;
}
+
+l3end:
+ while (pa < endpa) {
+ if (l2 == NULL || pmap_l1_index(va) != l1slot) {
+ /* Need to alloc another page table. */
+ l2 = pmap_early_alloc_tables(&freemempos, 1);
+
+ /* Link it. */
+ l1slot = pmap_l1_index(va);
+ pmap_store(&l1[l1slot],
+ L1_PDE((vm_paddr_t)l2, PTE_V));
+ }
+
+ if (l3 == NULL || pmap_l2_index(va) != l2slot) {
+ l3 = pmap_early_alloc_tables(&freemempos, 1);
+
+ /* Link it to L2. */
+ l2slot = pmap_l2_index(va);
+ pmap_store(&l2[l2slot],
+ L2_PDE((vm_paddr_t)l3, PTE_V));
+ }
+
+ /* map l3 pages */
+ l3slot = pmap_l3_index(va);
+ pmap_store(&l3[l3slot], L3_PTE(pa, PTE_KERN | memattr));
+
+ pa += L3_SIZE;
+ va += L3_SIZE;
+ }
}
/* And finally, the limit on DMAP VA. */

File Metadata

Mime Type
text/plain
Expires
Wed, Jul 22, 9:37 AM (8 h, 35 m)
Storage Engine
blob
Storage Format
Raw Data
Storage Handle
35359585
Default Alt Text
D54716.id.diff (4 KB)

Event Timeline