[PATCH v2 10/29] nios2: Cache handling

From: Ley Foon Tan
Date: Tue Jul 15 2014 - 04:54:52 EST


This patch adds functionality required for cache maintenance.

Signed-off-by: Ley Foon Tan <lftan@xxxxxxxxxx>
---
arch/nios2/include/asm/cache.h | 36 +++++
arch/nios2/include/asm/cacheflush.h | 54 ++++++++
arch/nios2/mm/cacheflush.c | 270 ++++++++++++++++++++++++++++++++++++
3 files changed, 360 insertions(+)
create mode 100644 arch/nios2/include/asm/cache.h
create mode 100644 arch/nios2/include/asm/cacheflush.h
create mode 100644 arch/nios2/mm/cacheflush.c

diff --git a/arch/nios2/include/asm/cache.h b/arch/nios2/include/asm/cache.h
new file mode 100644
index 0000000..2293cf5
--- /dev/null
+++ b/arch/nios2/include/asm/cache.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * 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 as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ */
+
+#ifndef _ASM_NIOS2_CACHE_H
+#define _ASM_NIOS2_CACHE_H
+
+#define NIOS2_DCACHE_SIZE CONFIG_NIOS2_DCACHE_SIZE
+#define NIOS2_ICACHE_SIZE CONFIG_NIOS2_ICACHE_SIZE
+#define NIOS2_DCACHE_LINE_SIZE CONFIG_NIOS2_DCACHE_LINE_SIZE
+#define NIOS2_ICACHE_LINE_SHIFT 5
+#define NIOS2_ICACHE_LINE_SIZE (1 << NIOS2_ICACHE_LINE_SHIFT)
+
+/* bytes per L1 cache line */
+#define L1_CACHE_SHIFT NIOS2_ICACHE_LINE_SHIFT
+#define L1_CACHE_BYTES NIOS2_ICACHE_LINE_SIZE
+
+#define ARCH_DMA_MINALIGN L1_CACHE_BYTES
+
+#define __cacheline_aligned
+#define ____cacheline_aligned
+
+#endif
diff --git a/arch/nios2/include/asm/cacheflush.h b/arch/nios2/include/asm/cacheflush.h
new file mode 100644
index 0000000..c9d34d7
--- /dev/null
+++ b/arch/nios2/include/asm/cacheflush.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2003 Microtronix Datacom Ltd.
+ * Copyright (C) 2000-2002 Greg Ungerer <gerg@xxxxxxxxxxxx>
+ *
+ * Ported from m68knommu.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS2_CACHEFLUSH_H
+#define _ASM_NIOS2_CACHEFLUSH_H
+
+#include <linux/mm_types.h>
+
+/*
+ * This flag is used to indicate that the page pointed to by a pte is clean
+ * and does not require cleaning before returning it to the user.
+ */
+#define PG_dcache_clean PG_arch_1
+
+struct mm_struct;
+
+extern void flush_cache_all(void);
+extern void flush_cache_mm(struct mm_struct *mm);
+extern void flush_cache_dup_mm(struct mm_struct *mm);
+extern void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end);
+extern void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
+ unsigned long pfn);
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
+extern void flush_dcache_page(struct page *page);
+
+extern void flush_icache_range(unsigned long start, unsigned long end);
+extern void flush_icache_page(struct vm_area_struct *vma, struct page *page);
+
+#define flush_cache_vmap(start, end) flush_dcache_range(start, end)
+#define flush_cache_vunmap(start, end) flush_dcache_range(start, end)
+
+extern void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long user_vaddr,
+ void *dst, void *src, int len);
+extern void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long user_vaddr,
+ void *dst, void *src, int len);
+
+extern void flush_dcache_range(unsigned long start, unsigned long end);
+extern void invalidate_dcache_range(unsigned long start, unsigned long end);
+
+#define flush_dcache_mmap_lock(mapping) do { } while (0)
+#define flush_dcache_mmap_unlock(mapping) do { } while (0)
+
+#endif /* _ASM_NIOS2_CACHEFLUSH_H */
diff --git a/arch/nios2/mm/cacheflush.c b/arch/nios2/mm/cacheflush.c
new file mode 100644
index 0000000..cf06a00
--- /dev/null
+++ b/arch/nios2/mm/cacheflush.c
@@ -0,0 +1,270 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009, Wind River Systems Inc
+ * Implemented by fredrik.markstrom@xxxxxxxxx and ivarholmqvist@xxxxxxxxx
+ */
+
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+
+#include <asm/cacheflush.h>
+#include <asm/cpuinfo.h>
+
+static void __flush_dcache(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ start &= ~(cpuinfo.dcache_line_size - 1);
+ end += (cpuinfo.dcache_line_size - 1);
+ end &= ~(cpuinfo.dcache_line_size - 1);
+
+ if (end > start + cpuinfo.dcache_size)
+ end = start + cpuinfo.dcache_size;
+
+ for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
+ __asm__ __volatile__ (" flushda 0(%0)\n"
+ : /* Outputs */
+ : /* Inputs */ "r"(addr)
+ /* : No clobber */);
+ }
+}
+
+static void __flush_dcache_all(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ start &= ~(cpuinfo.dcache_line_size - 1);
+ end += (cpuinfo.dcache_line_size - 1);
+ end &= ~(cpuinfo.dcache_line_size - 1);
+
+ if (end > start + cpuinfo.dcache_size)
+ end = start + cpuinfo.dcache_size;
+
+ for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
+ __asm__ __volatile__ (" flushd 0(%0)\n"
+ : /* Outputs */
+ : /* Inputs */ "r"(addr)
+ /* : No clobber */);
+ }
+}
+
+static void __invalidate_dcache(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ start &= ~(cpuinfo.dcache_line_size - 1);
+ end += (cpuinfo.dcache_line_size - 1);
+ end &= ~(cpuinfo.dcache_line_size - 1);
+
+ if (end > start + cpuinfo.dcache_size)
+ end = start + cpuinfo.dcache_size;
+
+ for (addr = start; addr < end; addr += cpuinfo.dcache_line_size) {
+ __asm__ __volatile__ (" initda 0(%0)\n"
+ : /* Outputs */
+ : /* Inputs */ "r"(addr)
+ /* : No clobber */);
+ }
+}
+
+static void __flush_icache(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ start &= ~(cpuinfo.icache_line_size - 1);
+ end += (cpuinfo.icache_line_size - 1);
+ end &= ~(cpuinfo.icache_line_size - 1);
+
+ if (end > start + cpuinfo.icache_size)
+ end = start + cpuinfo.icache_size;
+
+ for (addr = start; addr < end; addr += cpuinfo.icache_line_size) {
+ __asm__ __volatile__ (" flushi %0\n"
+ : /* Outputs */
+ : /* Inputs */ "r"(addr)
+ /* : No clobber */);
+ }
+ __asm__ __volatile(" flushp\n");
+}
+
+static void flush_aliases(struct address_space *mapping, struct page *page)
+{
+ struct mm_struct *mm = current->active_mm;
+ struct vm_area_struct *mpnt;
+ pgoff_t pgoff;
+
+ pgoff = page->index;
+
+ flush_dcache_mmap_lock(mapping);
+ vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
+ unsigned long offset;
+
+ if (mpnt->vm_mm != mm)
+ continue;
+ if (!(mpnt->vm_flags & VM_MAYSHARE))
+ continue;
+
+ offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
+ flush_cache_page(mpnt, mpnt->vm_start + offset,
+ page_to_pfn(page));
+ }
+ flush_dcache_mmap_unlock(mapping);
+}
+
+void flush_cache_all(void)
+{
+ __flush_dcache_all(0, cpuinfo.dcache_size);
+ __flush_icache(0, cpuinfo.icache_size);
+}
+
+void flush_cache_mm(struct mm_struct *mm)
+{
+ flush_cache_all();
+}
+
+void flush_cache_dup_mm(struct mm_struct *mm)
+{
+ flush_cache_all();
+}
+
+void flush_icache_range(unsigned long start, unsigned long end)
+{
+ __flush_icache(start, end);
+}
+
+void flush_dcache_range(unsigned long start, unsigned long end)
+{
+ __flush_dcache(start, end);
+}
+EXPORT_SYMBOL(flush_dcache_range);
+
+void invalidate_dcache_range(unsigned long start, unsigned long end)
+{
+ __invalidate_dcache(start, end);
+}
+EXPORT_SYMBOL(invalidate_dcache_range);
+
+void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
+ unsigned long end)
+{
+ __flush_dcache(start, end);
+ if (vma == NULL || (vma->vm_flags & VM_EXEC))
+ __flush_icache(start, end);
+}
+
+void flush_icache_page(struct vm_area_struct *vma, struct page *page)
+{
+ unsigned long start = (unsigned long) page_address(page);
+ unsigned long end = start + PAGE_SIZE;
+
+ __flush_icache(start, end);
+}
+
+void flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
+ unsigned long pfn)
+{
+ unsigned long start = vmaddr;
+ unsigned long end = start + PAGE_SIZE;
+
+ __flush_dcache(start, end);
+ if (vma->vm_flags & VM_EXEC)
+ __flush_icache(start, end);
+}
+
+void flush_dcache_page(struct page *page)
+{
+ struct address_space *mapping;
+
+ /*
+ * The zero page is never written to, so never has any dirty
+ * cache lines, and therefore never needs to be flushed.
+ */
+ if (page == ZERO_PAGE(0))
+ return;
+
+ mapping = page_mapping(page);
+
+ /* Flush this page if there are aliases. */
+ if (mapping && !mapping_mapped(mapping)) {
+ clear_bit(PG_dcache_clean, &page->flags);
+ } else {
+ unsigned long start = (unsigned long)page_address(page);
+ __flush_dcache_all(start, start + PAGE_SIZE);
+ if (mapping)
+ flush_aliases(mapping, page);
+ set_bit(PG_dcache_clean, &page->flags);
+ }
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+void update_mmu_cache(struct vm_area_struct *vma,
+ unsigned long address, pte_t *pte)
+{
+ unsigned long pfn = pte_pfn(*pte);
+ struct page *page;
+
+ if (!pfn_valid(pfn))
+ return;
+
+ /*
+ * The zero page is never written to, so never has any dirty
+ * cache lines, and therefore never needs to be flushed.
+ */
+ page = pfn_to_page(pfn);
+ if (page == ZERO_PAGE(0))
+ return;
+
+ if (!PageReserved(page) &&
+ !test_and_set_bit(PG_dcache_clean, &page->flags)) {
+ unsigned long start = page_to_virt(page);
+ struct address_space *mapping;
+
+ __flush_dcache(start, start + PAGE_SIZE);
+
+ mapping = page_mapping(page);
+ if (mapping)
+ flush_aliases(mapping, page);
+ }
+}
+
+void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
+ struct page *to)
+{
+ __flush_dcache(vaddr, vaddr + PAGE_SIZE);
+ copy_page(vto, vfrom);
+ __flush_dcache((unsigned long)vto, (unsigned long)vto + PAGE_SIZE);
+}
+
+void clear_user_page(void *addr, unsigned long vaddr, struct page *page)
+{
+ __flush_dcache(vaddr, vaddr + PAGE_SIZE);
+ clear_page(addr);
+ __flush_dcache((unsigned long)addr, (unsigned long)addr + PAGE_SIZE);
+}
+
+void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long user_vaddr,
+ void *dst, void *src, int len)
+{
+ flush_cache_page(vma, user_vaddr, page_to_pfn(page));
+ memcpy(dst, src, len);
+ __flush_dcache((unsigned long)src, (unsigned long)src + len);
+ if (vma->vm_flags & VM_EXEC)
+ __flush_icache((unsigned long)src, (unsigned long)src + len);
+}
+
+void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
+ unsigned long user_vaddr,
+ void *dst, void *src, int len)
+{
+ flush_cache_page(vma, user_vaddr, page_to_pfn(page));
+ memcpy(dst, src, len);
+ __flush_dcache((unsigned long)dst, (unsigned long)dst + len);
+ if (vma->vm_flags & VM_EXEC)
+ __flush_icache((unsigned long)dst, (unsigned long)dst + len);
+}
--
1.8.2.1

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