Merge Qualcom Hexagon architecture

This is the fifth version of the patchset (with one tiny whitespace fix)
to the Linux kernel to support the Qualcomm Hexagon architecture.

Between now and the next pull requests, Richard Kuo should have his key
signed, etc., and should be back on kernel.org.  In the meantime, this
got merged as a emailed patch-series.

* Hexagon: (36 commits)
  Add extra arch overrides to asm-generic/checksum.h
  Hexagon: Add self to MAINTAINERS
  Hexagon: Add basic stacktrace functionality for Hexagon architecture.
  Hexagon: Add configuration and makefiles for the Hexagon architecture.
  Hexagon: Comet platform support
  Hexagon: kgdb support files
  Hexagon: Add page-fault support.
  Hexagon: Add page table header files & etc.
  Hexagon: Add ioremap support
  Hexagon: Provide DMA implementation
  Hexagon: Implement basic TLB management routines for Hexagon.
  Hexagon: Implement basic cache-flush support
  Hexagon: Provide basic implementation and/or stubs for I/O routines.
  Hexagon: Add user access functions
  Hexagon: Add locking types and functions
  Hexagon: Add SMP support
  Hexagon: Provide basic debugging and system trap support.
  Hexagon: Add ptrace support
  Hexagon: Add time and timer functions
  Hexagon: Add interrupts
  ...

1 files changed, 100 insertions, 0 deletions

diff --git a/arch/hexagon/include/asm/mmu_context.h b/arch/hexagon/include/asm/mmu_context.h
new file mode 100644
index 0000000..b4fe5a5
--- /dev/null
+++ b/arch/hexagon/include/asm/mmu_context.h
@@ -0,0 +1,100 @@
+/*
+ * MM context support for the Hexagon architecture
+ *
+ * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#ifndef _ASM_MMU_CONTEXT_H
+#define _ASM_MMU_CONTEXT_H
+
+#include <asm/setup.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/mem-layout.h>
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+/*
+ * VM port hides all TLB management, so "lazy TLB" isn't very
+ * meaningful.  Even for ports to architectures with visble TLBs,
+ * this is almost invariably a null function.
+ */
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+	struct task_struct *tsk)
+{
+}
+
+/*
+ * Architecture-specific actions, if any, for memory map deactivation.
+ */
+static inline void deactivate_mm(struct task_struct *tsk,
+	struct mm_struct *mm)
+{
+}
+
+/**
+ * init_new_context - initialize context related info for new mm_struct instance
+ * @tsk: pointer to a task struct
+ * @mm: pointer to a new mm struct
+ */
+static inline int init_new_context(struct task_struct *tsk,
+					struct mm_struct *mm)
+{
+	/* mm->context is set up by pgd_alloc */
+	return 0;
+}
+
+/*
+ *  Switch active mm context
+ */
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+				struct task_struct *tsk)
+{
+	int l1;
+
+	/*
+	 * For virtual machine, we have to update system map if it's been
+	 * touched.
+	 */
+	if (next->context.generation < prev->context.generation) {
+		for (l1 = MIN_KERNEL_SEG; l1 <= max_kernel_seg; l1++)
+			next->pgd[l1] = init_mm.pgd[l1];
+
+		next->context.generation = prev->context.generation;
+	}
+
+	__vmnewmap((void *)next->context.ptbase);
+}
+
+/*
+ *  Activate new memory map for task
+ */
+static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	switch_mm(prev, next, current_thread_info()->task);
+	local_irq_restore(flags);
+}
+
+/*  Generic hooks for arch_dup_mmap and arch_exit_mmap  */
+#include <asm-generic/mm_hooks.h>
+
+#endif