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, 157 insertions, 0 deletions

diff --git a/arch/hexagon/include/asm/page.h b/arch/hexagon/include/asm/page.h
new file mode 100644
index 0000000..edd9762
--- /dev/null
+++ b/arch/hexagon/include/asm/page.h
@@ -0,0 +1,157 @@
+/*
+ * Page management definitions 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_PAGE_H
+#define _ASM_PAGE_H
+
+#include <linux/const.h>
+
+/*  This is probably not the most graceful way to handle this.  */
+
+#ifdef CONFIG_PAGE_SIZE_4KB
+#define PAGE_SHIFT 12
+#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_4KB
+#endif
+
+#ifdef CONFIG_PAGE_SIZE_16KB
+#define PAGE_SHIFT 14
+#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_16KB
+#endif
+
+#ifdef CONFIG_PAGE_SIZE_64KB
+#define PAGE_SHIFT 16
+#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_64KB
+#endif
+
+#ifdef CONFIG_PAGE_SIZE_256KB
+#define PAGE_SHIFT 18
+#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_256KB
+#endif
+
+#ifdef CONFIG_PAGE_SIZE_1MB
+#define PAGE_SHIFT 20
+#define HEXAGON_L1_PTE_SIZE __HVM_PDE_S_1MB
+#endif
+
+/*
+ *  These should be defined in hugetlb.h, but apparently not.
+ *  "Huge" for us should be 4MB or 16MB, which are both represented
+ *  in L1 PTE's.  Right now, it's set up for 4MB.
+ */
+#ifdef CONFIG_HUGETLB_PAGE
+#define HPAGE_SHIFT 22
+#define HPAGE_SIZE (1UL << HPAGE_SHIFT)
+#define HPAGE_MASK (~(HPAGE_SIZE-1))
+#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT-PAGE_SHIFT)
+#define HVM_HUGEPAGE_SIZE 0x5
+#endif
+
+#define PAGE_SIZE  (1UL << PAGE_SHIFT)
+#define PAGE_MASK  (~((1 << PAGE_SHIFT) - 1))
+
+#ifdef __KERNEL__
+#ifndef __ASSEMBLY__
+
+/*
+ * This is for PFN_DOWN, which mm.h needs.  Seems the right place to pull it in.
+ */
+#include <linux/pfn.h>
+
+/*
+ * We implement a two-level architecture-specific page table structure.
+ * Null intermediate page table level (pmd, pud) definitions will come from
+ * asm-generic/pagetable-nopmd.h and asm-generic/pagetable-nopud.h
+ */
+typedef struct { unsigned long pte; } pte_t;
+typedef struct { unsigned long pgd; } pgd_t;
+typedef struct { unsigned long pgprot; } pgprot_t;
+typedef struct page *pgtable_t;
+
+#define pte_val(x)     ((x).pte)
+#define pgd_val(x)     ((x).pgd)
+#define pgprot_val(x)  ((x).pgprot)
+#define __pte(x)       ((pte_t) { (x) })
+#define __pgd(x)       ((pgd_t) { (x) })
+#define __pgprot(x)    ((pgprot_t) { (x) })
+
+/*
+ * We need a __pa and a __va routine for kernel space.
+ * MIPS says they're only used during mem_init.
+ * also, check if we need a PHYS_OFFSET.
+ */
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET)
+#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
+
+/* The "page frame" descriptor is defined in linux/mm.h */
+struct page;
+
+/* Returns page frame descriptor for virtual address. */
+#define virt_to_page(kaddr) pfn_to_page(PFN_DOWN(__pa(kaddr)))
+
+/* Default vm area behavior is non-executable.  */
+#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | \
+				VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define pfn_valid(pfn) ((pfn) < max_mapnr)
+#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+
+/*  Need to not use a define for linesize; may move this to another file.  */
+static inline void clear_page(void *page)
+{
+	/*  This can only be done on pages with L1 WB cache */
+	asm volatile(
+		"	loop0(1f,%1);\n"
+		"1:	{ dczeroa(%0);\n"
+		"	  %0 = add(%0,#32); }:endloop0\n"
+		: "+r" (page)
+		: "r" (PAGE_SIZE/32)
+		: "lc0", "sa0", "memory"
+	);
+}
+
+#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)
+
+/*
+ * Under assumption that kernel always "sees" user map...
+ */
+#define clear_user_page(page, vaddr, pg)	clear_page(page)
+#define copy_user_page(to, from, vaddr, pg)	copy_page(to, from)
+
+/*
+ * page_to_phys - convert page to physical address
+ * @page - pointer to page entry in mem_map
+ */
+#define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
+
+/*
+ * For port to Hexagon Virtual Machine, MAYBE we check for attempts
+ * to reference reserved HVM space, but in any case, the VM will be
+ * protected.
+ */
+#define kern_addr_valid(addr)   (1)
+
+#include <asm-generic/memory_model.h>
+/* XXX Todo: implement assembly-optimized version of getorder. */
+#include <asm-generic/getorder.h>
+
+#endif /* ifdef __ASSEMBLY__ */
+#endif /* ifdef __KERNEL__ */
+
+#endif