[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/arc/mm/dma.c b/src/kernel/linux/v4.14/arch/arc/mm/dma.c
new file mode 100644
index 0000000..e9d9360
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/arc/mm/dma.c
@@ -0,0 +1,278 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * DMA Coherent API Notes
+ *
+ * I/O is inherently non-coherent on ARC. So a coherent DMA buffer is
+ * implemented by accessing it using a kernel virtual address, with
+ * Cache bit off in the TLB entry.
+ *
+ * The default DMA address == Phy address which is 0x8000_0000 based.
+ */
+
+#include <linux/dma-mapping.h>
+#include <asm/cache.h>
+#include <asm/cacheflush.h>
+
+
+static void *arc_dma_alloc(struct device *dev, size_t size,
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+{
+	unsigned long order = get_order(size);
+	struct page *page;
+	phys_addr_t paddr;
+	void *kvaddr;
+	int need_coh = 1, need_kvaddr = 0;
+
+	page = alloc_pages(gfp, order);
+	if (!page)
+		return NULL;
+
+	/*
+	 * IOC relies on all data (even coherent DMA data) being in cache
+	 * Thus allocate normal cached memory
+	 *
+	 * The gains with IOC are two pronged:
+	 *   -For streaming data, elides need for cache maintenance, saving
+	 *    cycles in flush code, and bus bandwidth as all the lines of a
+	 *    buffer need to be flushed out to memory
+	 *   -For coherent data, Read/Write to buffers terminate early in cache
+	 *   (vs. always going to memory - thus are faster)
+	 */
+	if ((is_isa_arcv2() && ioc_enable) ||
+	    (attrs & DMA_ATTR_NON_CONSISTENT))
+		need_coh = 0;
+
+	/*
+	 * - A coherent buffer needs MMU mapping to enforce non-cachability
+	 * - A highmem page needs a virtual handle (hence MMU mapping)
+	 *   independent of cachability
+	 */
+	if (PageHighMem(page) || need_coh)
+		need_kvaddr = 1;
+
+	/* This is linear addr (0x8000_0000 based) */
+	paddr = page_to_phys(page);
+
+	*dma_handle = plat_phys_to_dma(dev, paddr);
+
+	/* This is kernel Virtual address (0x7000_0000 based) */
+	if (need_kvaddr) {
+		kvaddr = ioremap_nocache(paddr, size);
+		if (kvaddr == NULL) {
+			__free_pages(page, order);
+			return NULL;
+		}
+	} else {
+		kvaddr = (void *)(u32)paddr;
+	}
+
+	/*
+	 * Evict any existing L1 and/or L2 lines for the backing page
+	 * in case it was used earlier as a normal "cached" page.
+	 * Yeah this bit us - STAR 9000898266
+	 *
+	 * Although core does call flush_cache_vmap(), it gets kvaddr hence
+	 * can't be used to efficiently flush L1 and/or L2 which need paddr
+	 * Currently flush_cache_vmap nukes the L1 cache completely which
+	 * will be optimized as a separate commit
+	 */
+	if (need_coh)
+		dma_cache_wback_inv(paddr, size);
+
+	return kvaddr;
+}
+
+static void arc_dma_free(struct device *dev, size_t size, void *vaddr,
+		dma_addr_t dma_handle, unsigned long attrs)
+{
+	phys_addr_t paddr = plat_dma_to_phys(dev, dma_handle);
+	struct page *page = virt_to_page(paddr);
+	int is_non_coh = 1;
+
+	is_non_coh = (attrs & DMA_ATTR_NON_CONSISTENT) ||
+			(is_isa_arcv2() && ioc_enable);
+
+	if (PageHighMem(page) || !is_non_coh)
+		iounmap((void __force __iomem *)vaddr);
+
+	__free_pages(page, get_order(size));
+}
+
+static int arc_dma_mmap(struct device *dev, struct vm_area_struct *vma,
+			void *cpu_addr, dma_addr_t dma_addr, size_t size,
+			unsigned long attrs)
+{
+	unsigned long user_count = vma_pages(vma);
+	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	unsigned long pfn = __phys_to_pfn(plat_dma_to_phys(dev, dma_addr));
+	unsigned long off = vma->vm_pgoff;
+	int ret = -ENXIO;
+
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
+		return ret;
+
+	if (off < count && user_count <= (count - off)) {
+		ret = remap_pfn_range(vma, vma->vm_start,
+				      pfn + off,
+				      user_count << PAGE_SHIFT,
+				      vma->vm_page_prot);
+	}
+
+	return ret;
+}
+
+/*
+ * streaming DMA Mapping API...
+ * CPU accesses page via normal paddr, thus needs to explicitly made
+ * consistent before each use
+ */
+static void _dma_cache_sync(phys_addr_t paddr, size_t size,
+		enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_FROM_DEVICE:
+		dma_cache_inv(paddr, size);
+		break;
+	case DMA_TO_DEVICE:
+		dma_cache_wback(paddr, size);
+		break;
+	case DMA_BIDIRECTIONAL:
+		dma_cache_wback_inv(paddr, size);
+		break;
+	default:
+		pr_err("Invalid DMA dir [%d] for OP @ %pa[p]\n", dir, &paddr);
+	}
+}
+
+/*
+ * arc_dma_map_page - map a portion of a page for streaming DMA
+ *
+ * Ensure that any data held in the cache is appropriately discarded
+ * or written back.
+ *
+ * The device owns this memory once this call has completed.  The CPU
+ * can regain ownership by calling dma_unmap_page().
+ *
+ * Note: while it takes struct page as arg, caller can "abuse" it to pass
+ * a region larger than PAGE_SIZE, provided it is physically contiguous
+ * and this still works correctly
+ */
+static dma_addr_t arc_dma_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		unsigned long attrs)
+{
+	phys_addr_t paddr = page_to_phys(page) + offset;
+
+	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+		_dma_cache_sync(paddr, size, dir);
+
+	return plat_phys_to_dma(dev, paddr);
+}
+
+/*
+ * arc_dma_unmap_page - unmap a buffer previously mapped through dma_map_page()
+ *
+ * After this call, reads by the CPU to the buffer are guaranteed to see
+ * whatever the device wrote there.
+ *
+ * Note: historically this routine was not implemented for ARC
+ */
+static void arc_dma_unmap_page(struct device *dev, dma_addr_t handle,
+			       size_t size, enum dma_data_direction dir,
+			       unsigned long attrs)
+{
+	phys_addr_t paddr = plat_dma_to_phys(dev, handle);
+
+	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
+		_dma_cache_sync(paddr, size, dir);
+}
+
+static int arc_dma_map_sg(struct device *dev, struct scatterlist *sg,
+	   int nents, enum dma_data_direction dir, unsigned long attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i)
+		s->dma_address = dma_map_page(dev, sg_page(s), s->offset,
+					       s->length, dir);
+
+	return nents;
+}
+
+static void arc_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
+			     int nents, enum dma_data_direction dir,
+			     unsigned long attrs)
+{
+	struct scatterlist *s;
+	int i;
+
+	for_each_sg(sg, s, nents, i)
+		arc_dma_unmap_page(dev, sg_dma_address(s), sg_dma_len(s), dir,
+				   attrs);
+}
+
+static void arc_dma_sync_single_for_cpu(struct device *dev,
+		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
+{
+	_dma_cache_sync(plat_dma_to_phys(dev, dma_handle), size, DMA_FROM_DEVICE);
+}
+
+static void arc_dma_sync_single_for_device(struct device *dev,
+		dma_addr_t dma_handle, size_t size, enum dma_data_direction dir)
+{
+	_dma_cache_sync(plat_dma_to_phys(dev, dma_handle), size, DMA_TO_DEVICE);
+}
+
+static void arc_dma_sync_sg_for_cpu(struct device *dev,
+		struct scatterlist *sglist, int nelems,
+		enum dma_data_direction dir)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
+		_dma_cache_sync(sg_phys(sg), sg->length, dir);
+}
+
+static void arc_dma_sync_sg_for_device(struct device *dev,
+		struct scatterlist *sglist, int nelems,
+		enum dma_data_direction dir)
+{
+	int i;
+	struct scatterlist *sg;
+
+	for_each_sg(sglist, sg, nelems, i)
+		_dma_cache_sync(sg_phys(sg), sg->length, dir);
+}
+
+static int arc_dma_supported(struct device *dev, u64 dma_mask)
+{
+	/* Support 32 bit DMA mask exclusively */
+	return dma_mask == DMA_BIT_MASK(32);
+}
+
+const struct dma_map_ops arc_dma_ops = {
+	.alloc			= arc_dma_alloc,
+	.free			= arc_dma_free,
+	.mmap			= arc_dma_mmap,
+	.map_page		= arc_dma_map_page,
+	.unmap_page		= arc_dma_unmap_page,
+	.map_sg			= arc_dma_map_sg,
+	.unmap_sg		= arc_dma_unmap_sg,
+	.sync_single_for_device	= arc_dma_sync_single_for_device,
+	.sync_single_for_cpu	= arc_dma_sync_single_for_cpu,
+	.sync_sg_for_cpu	= arc_dma_sync_sg_for_cpu,
+	.sync_sg_for_device	= arc_dma_sync_sg_for_device,
+	.dma_supported		= arc_dma_supported,
+};
+EXPORT_SYMBOL(arc_dma_ops);