@@ -473,7 +473,6 @@ ENDPROC(cpu_init)
create_page_tables:
/* Prepare the page-tables for mapping Xen */
mov_w r0, XEN_VIRT_START
- create_table_entry boot_pgtable, boot_second, r0, 1
/*
* We need to use a stash register because
@@ -519,70 +518,37 @@ create_page_tables:
cmp r1, r0 /* Loop until we map all of Xen */
blo 1b
- /*
- * If Xen is loaded at exactly XEN_VIRT_START then we don't
- * need an additional 1:1 mapping, the virtual mapping will
- * suffice.
- */
- cmp r9, #XEN_VIRT_START
- moveq pc, lr
-
/*
* Setup the 1:1 mapping so we can turn the MMU on. Note that
* only the first page of Xen will be part of the 1:1 mapping.
- *
- * In all the cases, we will link boot_third_id. So create the
- * mapping in advance.
*/
+ create_table_entry boot_pgtable, boot_second_id, r9, 1
+ create_table_entry boot_second_id, boot_third_id, r9, 2
create_mapping_entry boot_third_id, r9, r9
/*
- * Find the first slot used. If the slot is not XEN_FIRST_SLOT,
- * then the 1:1 mapping will use its own set of page-tables from
- * the second level.
+ * Find the first slot used. If the slot is not the same
+ * as TEMPORARY_AREA_FIRST_SLOT, then we will want to switch
+ * to the temporary mapping before jumping to the runtime
+ * virtual mapping.
*/
get_table_slot r1, r9, 1 /* r1 := first slot */
- cmp r1, #XEN_FIRST_SLOT
- beq 1f
- create_table_entry boot_pgtable, boot_second_id, r9, 1
- b link_from_second_id
-
-1:
- /*
- * Find the second slot used. If the slot is XEN_SECOND_SLOT, then the
- * 1:1 mapping will use its own set of page-tables from the
- * third level.
- */
- get_table_slot r1, r9, 2 /* r1 := second slot */
- cmp r1, #XEN_SECOND_SLOT
- beq virtphys_clash
- create_table_entry boot_second, boot_third_id, r9, 2
- b link_from_third_id
+ cmp r1, #TEMPORARY_AREA_FIRST_SLOT
+ bne use_temporary_mapping
-link_from_second_id:
- create_table_entry boot_second_id, boot_third_id, r9, 2
-link_from_third_id:
- /* Good news, we are not clashing with Xen virtual mapping */
+ mov_w r0, XEN_VIRT_START
+ create_table_entry boot_pgtable, boot_second, r0, 1
mov r12, #0 /* r12 := temporary mapping not created */
mov pc, lr
-virtphys_clash:
+use_temporary_mapping:
/*
- * The identity map clashes with boot_third. Link boot_first_id and
- * map Xen to a temporary mapping. See switch_to_runtime_mapping
- * for more details.
+ * The identity mapping is not using the first slot
+ * TEMPORARY_AREA_FIRST_SLOT. Create a temporary mapping.
+ * See switch_to_runtime_mapping for more details.
*/
- PRINT("- Virt and Phys addresses clash -\r\n")
PRINT("- Create temporary mapping -\r\n")
- /*
- * This will override the link to boot_second in XEN_FIRST_SLOT.
- * The page-tables are not live yet. So no need to use
- * break-before-make.
- */
- create_table_entry boot_pgtable, boot_second_id, r9, 1
- create_table_entry boot_second_id, boot_third_id, r9, 2
-
/* Map boot_second (cover Xen mappings) to the temporary 1st slot */
mov_w r0, TEMPORARY_XEN_VIRT_START
create_table_entry boot_pgtable, boot_second, r0, 1
@@ -720,33 +686,13 @@ remove_identity_mapping:
/* r2:r3 := invalid page-table entry */
mov r2, #0x0
mov r3, #0x0
- /*
- * Find the first slot used. Remove the entry for the first
- * table if the slot is not XEN_FIRST_SLOT.
- */
+
+ /* Find the first slot used and remove it */
get_table_slot r1, r9, 1 /* r1 := first slot */
- cmp r1, #XEN_FIRST_SLOT
- beq 1f
- /* It is not in slot 0, remove the entry */
mov_w r0, boot_pgtable /* r0 := root table */
lsl r1, r1, #3 /* r1 := Slot offset */
strd r2, r3, [r0, r1]
- b identity_mapping_removed
-
-1:
- /*
- * Find the second slot used. Remove the entry for the first
- * table if the slot is not XEN_SECOND_SLOT.
- */
- get_table_slot r1, r9, 2 /* r1 := second slot */
- cmp r1, #XEN_SECOND_SLOT
- beq identity_mapping_removed
- /* It is not in slot 1, remove the entry */
- mov_w r0, boot_second /* r0 := second table */
- lsl r1, r1, #3 /* r1 := Slot offset */
- strd r2, r3, [r0, r1]
-identity_mapping_removed:
flush_xen_tlb_local r0
mov pc, lr
ENDPROC(remove_identity_mapping)