Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c
index c75d5c3..73a7e88 100644
--- a/arch/arc/mm/dma.c
+++ b/arch/arc/mm/dma.c
@@ -1,9 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * 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.
  */
 
 #include <linux/dma-noncoherent.h>
@@ -11,51 +8,15 @@
 #include <asm/cacheflush.h>
 
 /*
- * ARCH specific callbacks for generic noncoherent DMA ops (dma/noncoherent.c)
+ * ARCH specific callbacks for generic noncoherent DMA ops
  *  - hardware IOC not available (or "dma-coherent" not set for device in DT)
  *  - But still handle both coherent and non-coherent requests from caller
  *
  * For DMA coherent hardware (IOC) generic code suffices
  */
-void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, unsigned long attrs)
+
+void arch_dma_prep_coherent(struct page *page, size_t size)
 {
-	unsigned long order = get_order(size);
-	struct page *page;
-	phys_addr_t paddr;
-	void *kvaddr;
-	bool need_coh = !(attrs & DMA_ATTR_NON_CONSISTENT);
-
-	/*
-	 * __GFP_HIGHMEM flag is cleared by upper layer functions
-	 * (in include/linux/dma-mapping.h) so we should never get a
-	 * __GFP_HIGHMEM here.
-	 */
-	BUG_ON(gfp & __GFP_HIGHMEM);
-
-	page = alloc_pages(gfp, order);
-	if (!page)
-		return NULL;
-
-	/* This is linear addr (0x8000_0000 based) */
-	paddr = page_to_phys(page);
-
-	*dma_handle = paddr;
-
-	/*
-	 * A coherent buffer needs MMU mapping to enforce non-cachability.
-	 * kvaddr is kernel Virtual address (0x7000_0000 based).
-	 */
-	if (need_coh) {
-		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.
@@ -66,47 +27,7 @@
 	 * 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;
-}
-
-void arch_dma_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t dma_handle, unsigned long attrs)
-{
-	phys_addr_t paddr = dma_handle;
-	struct page *page = virt_to_page(paddr);
-
-	if (!(attrs & DMA_ATTR_NON_CONSISTENT))
-		iounmap((void __force __iomem *)vaddr);
-
-	__free_pages(page, get_order(size));
-}
-
-int arch_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(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;
+	dma_cache_wback_inv(page_to_phys(page), size);
 }
 
 /*
@@ -167,7 +88,7 @@
 }
 
 /*
- * Plug in coherent or noncoherent dma ops
+ * Plug in direct dma map ops.
  */
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 			const struct iommu_ops *iommu, bool coherent)
@@ -175,13 +96,11 @@
 	/*
 	 * IOC hardware snoops all DMA traffic keeping the caches consistent
 	 * with memory - eliding need for any explicit cache maintenance of
-	 * DMA buffers - so we can use dma_direct cache ops.
+	 * DMA buffers.
 	 */
-	if (is_isa_arcv2() && ioc_enable && coherent) {
-		set_dma_ops(dev, &dma_direct_ops);
-		dev_info(dev, "use dma_direct_ops cache ops\n");
-	} else {
-		set_dma_ops(dev, &dma_noncoherent_ops);
-		dev_info(dev, "use dma_noncoherent_ops cache ops\n");
-	}
+	if (is_isa_arcv2() && ioc_enable && coherent)
+		dev->dma_coherent = true;
+
+	dev_info(dev, "use %scoherent DMA ops\n",
+		 dev->dma_coherent ? "" : "non");
 }