summaryrefslogtreecommitdiffstats
path: root/kernel/arch/mn10300/mm/mmu-context.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/arch/mn10300/mm/mmu-context.c')
-rw-r--r--kernel/arch/mn10300/mm/mmu-context.c62
1 files changed, 62 insertions, 0 deletions
diff --git a/kernel/arch/mn10300/mm/mmu-context.c b/kernel/arch/mn10300/mm/mmu-context.c
new file mode 100644
index 000000000..a4f7d3dcc
--- /dev/null
+++ b/kernel/arch/mn10300/mm/mmu-context.c
@@ -0,0 +1,62 @@
+/* MN10300 MMU context allocation and management
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/mmu_context.h>
+#include <asm/tlbflush.h>
+
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+/*
+ * list of the MMU contexts last allocated on each CPU
+ */
+unsigned long mmu_context_cache[NR_CPUS] = {
+ [0 ... NR_CPUS - 1] =
+ MMU_CONTEXT_FIRST_VERSION * 2 - (1 - MMU_CONTEXT_TLBPID_LOCK_NR),
+};
+#endif /* CONFIG_MN10300_TLB_USE_PIDR */
+
+/*
+ * preemptively set a TLB entry
+ */
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
+{
+ unsigned long pteu, ptel, cnx, flags;
+ pte_t pte = *ptep;
+
+ addr &= PAGE_MASK;
+ ptel = pte_val(pte) & ~(xPTEL_UNUSED1 | xPTEL_UNUSED2);
+
+ /* make sure the context doesn't migrate and defend against
+ * interference from vmalloc'd regions */
+ local_irq_save(flags);
+
+ cnx = ~MMU_NO_CONTEXT;
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+ cnx = mm_context(vma->vm_mm);
+#endif
+
+ if (cnx != MMU_NO_CONTEXT) {
+ pteu = addr;
+#ifdef CONFIG_MN10300_TLB_USE_PIDR
+ pteu |= cnx & MMU_CONTEXT_TLBPID_MASK;
+#endif
+ if (!(pte_val(pte) & _PAGE_NX)) {
+ IPTEU = pteu;
+ if (IPTEL & xPTEL_V)
+ IPTEL = ptel;
+ }
+ DPTEU = pteu;
+ if (DPTEL & xPTEL_V)
+ DPTEL = ptel;
+ }
+
+ local_irq_restore(flags);
+}