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, 58 insertions, 0 deletions

diff --git a/arch/hexagon/include/asm/tlbflush.h b/arch/hexagon/include/asm/tlbflush.h
new file mode 100644
index 0000000..b89a902
--- /dev/null
+++ b/arch/hexagon/include/asm/tlbflush.h
@@ -0,0 +1,58 @@
+/*
+ * TLB flush support for Hexagon
+ *
+ * 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_TLBFLUSH_H
+#define _ASM_TLBFLUSH_H
+
+#include <linux/mm.h>
+#include <asm/processor.h>
+
+/*
+ * TLB flushing -- in "SMP", these routines get defined to be the
+ * ones from smp.c, else they are some local flavors.
+ */
+
+/*
+ * These functions are commonly macros, but in the interests of
+ * VM vs. native implementation and code size, we simply declare
+ * the function prototypes here.
+ */
+extern void tlb_flush_all(void);
+extern void flush_tlb_mm(struct mm_struct *mm);
+extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr);
+extern void flush_tlb_range(struct vm_area_struct *vma,
+				unsigned long start, unsigned long end);
+extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
+extern void flush_tlb_one(unsigned long);
+
+/*
+ * "This is called in munmap when we have freed up some page-table pages.
+ * We don't need to do anything here..."
+ *
+ * The VM kernel doesn't walk page tables, and they are passed to the VMM
+ * by logical address. There doesn't seem to be any possibility that they
+ * could be referenced by the VM kernel based on a stale mapping, since
+ * they would only be located by consulting the mm structure, and they
+ * will have been purged from that structure by the munmap.  Seems like
+ * a noop on HVM as well.
+ */
+#define flush_tlb_pgtables(mm, start, end)
+
+#endif