patch-2.1.101 linux/arch/arm/mm/mm-arc.c

• Lines: 80
• Date: Fri May 8 00:42:38 1998
• Orig file: v2.1.100/linux/arch/arm/mm/mm-arc.c
• Orig date: Tue Apr 14 14:29:20 1998

diff -u --recursive --new-file v2.1.100/linux/arch/arm/mm/mm-arc.c linux/arch/arm/mm/mm-arc.c
@@ -5,4 +5,78 @@
  *
  * Copyright (C) 1998 Russell King
  */
-#include <asm/arch/mm-init.h>
+#include <asm/hardware.h>
+#include <asm/pgtable.h>
+
+unsigned long phys_screen_end;
+
+/*
+ * This routine needs more work to make it dynamically release/allocate mem!
+ */
+unsigned long map_screen_mem(unsigned long log_start, unsigned long kmem, int update)
+{
+	static int updated = 0;
+
+	if (updated)
+		return 0;
+
+	updated = update;
+
+	if (update) {
+		unsigned long address = log_start, offset;
+		pgd_t *pgdp;
+
+		kmem = (kmem + 3) & ~3;
+
+		pgdp = pgd_offset (&init_mm, address);				/* +31 */
+		offset = SCREEN_START;
+		while (address < SCREEN1_END) {
+			unsigned long addr_pmd, end_pmd;
+			pmd_t *pmdp;
+
+			/* if (pgd_none (*pgdp)) alloc pmd */
+			pmdp = pmd_offset (pgdp, address);			/* +0 */
+			addr_pmd = address & ~PGDIR_MASK;			/* 088000 */
+			end_pmd = addr_pmd + SCREEN1_END - address;		/* 100000 */
+			if (end_pmd > PGDIR_SIZE)
+				end_pmd = PGDIR_SIZE;
+
+			do {
+				unsigned long addr_pte, end_pte;
+				pte_t *ptep;
+
+				if (pmd_none (*pmdp)) {
+					pte_t *new_pte = (pte_t *)kmem;
+					kmem += PTRS_PER_PTE * BYTES_PER_PTR;
+					memzero (new_pte, PTRS_PER_PTE * BYTES_PER_PTR);
+					set_pmd (pmdp, mk_pmd(new_pte));
+				}
+
+				ptep = pte_offset (pmdp, addr_pmd);		/* +11 */
+				addr_pte = addr_pmd & ~PMD_MASK;		/* 088000 */
+				end_pte = addr_pte + end_pmd - addr_pmd;	/* 100000 */
+				if (end_pte > PMD_SIZE)
+					end_pte = PMD_SIZE;
+
+				do {
+					set_pte (ptep, mk_pte(offset, PAGE_KERNEL));
+					addr_pte += PAGE_SIZE;
+					offset += PAGE_SIZE;
+					ptep++;
+				} while (addr_pte < end_pte);
+
+				pmdp++;
+				addr_pmd = (addr_pmd + PMD_SIZE) & PMD_MASK;
+			} while (addr_pmd < end_pmd);
+
+			address = (address + PGDIR_SIZE) & PGDIR_MASK;
+			pgdp ++;
+		}
+
+		phys_screen_end = offset;
+		flush_tlb_all ();
+		update_mm_cache_all ();
+	}
+	return kmem;
+}
+