--- zzzz-none-000/linux-3.10.107/arch/mips/mm/cache.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/mips/mm/cache.c	2021-02-04 17:41:59.000000000 +0000
@@ -8,7 +8,6 @@
  */
 #include <linux/fs.h>
 #include <linux/fcntl.h>
-#include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/linkage.h>
 #include <linux/module.h>
@@ -17,6 +16,7 @@
 #include <linux/mm.h>
 
 #include <asm/cacheflush.h>
+#include <asm/highmem.h>
 #include <asm/processor.h>
 #include <asm/cpu.h>
 #include <asm/cpu-features.h>
@@ -30,15 +30,18 @@
 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
 	unsigned long pfn);
 void (*flush_icache_range)(unsigned long start, unsigned long end);
+EXPORT_SYMBOL_GPL(flush_icache_range);
 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
+EXPORT_SYMBOL_GPL(local_flush_icache_range);
 
 void (*__flush_cache_vmap)(void);
 void (*__flush_cache_vunmap)(void);
 
 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
-void (*__invalidate_kernel_vmap_range)(unsigned long vaddr, int size);
-
 EXPORT_SYMBOL_GPL(__flush_kernel_vmap_range);
+EXPORT_SYMBOL(flush_cache_all);
+EXPORT_SYMBOL(__flush_cache_all);
+void (*__invalidate_kernel_vmap_range)(unsigned long vaddr, int size);
 
 /* MIPS specific cache operations */
 void (*flush_cache_sigtramp)(unsigned long addr);
@@ -50,7 +53,7 @@
 EXPORT_SYMBOL(flush_data_cache_page);
 EXPORT_SYMBOL(flush_icache_all);
 
-#ifdef CONFIG_DMA_NONCOHERENT
+#if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
 
 /* DMA cache operations. */
 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
@@ -58,8 +61,10 @@
 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
 
 EXPORT_SYMBOL(_dma_cache_wback_inv);
+EXPORT_SYMBOL(_dma_cache_inv);
+EXPORT_SYMBOL(_dma_cache_wback);
 
-#endif /* CONFIG_DMA_NONCOHERENT */
+#endif /* CONFIG_DMA_NONCOHERENT || CONFIG_DMA_MAYBE_COHERENT */
 
 /*
  * We could optimize the case where the cache argument is not BCACHE but
@@ -83,8 +88,6 @@
 	struct address_space *mapping = page_mapping(page);
 	unsigned long addr;
 
-	if (PageHighMem(page))
-		return;
 	if (mapping && !mapping_mapped(mapping)) {
 		SetPageDcacheDirty(page);
 		return;
@@ -95,8 +98,15 @@
 	 * case is for exec env/arg pages and those are %99 certainly going to
 	 * get faulted into the tlb (and thus flushed) anyways.
 	 */
-	addr = (unsigned long) page_address(page);
+	if (PageHighMem(page))
+		addr = (unsigned long)kmap_atomic(page);
+	else
+		addr = (unsigned long)page_address(page);
+
 	flush_data_cache_page(addr);
+
+	if (PageHighMem(page))
+		__kunmap_atomic((void *)addr);
 }
 
 EXPORT_SYMBOL(__flush_dcache_page);
@@ -119,21 +129,28 @@
 
 EXPORT_SYMBOL(__flush_anon_page);
 
-void __update_cache(struct vm_area_struct *vma, unsigned long address,
-	pte_t pte)
+void __update_cache(unsigned long address, pte_t pte)
 {
 	struct page *page;
 	unsigned long pfn, addr;
-	int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
+	int exec = !pte_no_exec(pte) && !cpu_has_ic_fills_f_dc;
 
 	pfn = pte_pfn(pte);
 	if (unlikely(!pfn_valid(pfn)))
 		return;
 	page = pfn_to_page(pfn);
-	if (page_mapping(page) && Page_dcache_dirty(page)) {
-		addr = (unsigned long) page_address(page);
+	if (Page_dcache_dirty(page)) {
+		if (PageHighMem(page))
+			addr = (unsigned long)kmap_atomic(page);
+		else
+			addr = (unsigned long)page_address(page);
+
 		if (exec || pages_do_alias(addr, address & PAGE_MASK))
 			flush_data_cache_page(addr);
+
+		if (PageHighMem(page))
+			__kunmap_atomic((void *)addr);
+
 		ClearPageDcacheDirty(page);
 	}
 }
@@ -148,18 +165,18 @@
 		protection_map[1]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 		protection_map[2]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 		protection_map[3]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
-		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
+		protection_map[4]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 		protection_map[5]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
-		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
+		protection_map[6]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 		protection_map[7]  = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 
 		protection_map[8]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_NO_READ);
 		protection_map[9]  = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC);
 		protection_map[10] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE | _PAGE_NO_READ);
 		protection_map[11] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_EXEC | _PAGE_WRITE);
-		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_NO_READ);
+		protection_map[12] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
 		protection_map[13] = __pgprot(_page_cachable_default | _PAGE_PRESENT);
-		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE  | _PAGE_NO_READ);
+		protection_map[14] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
 		protection_map[15] = __pgprot(_page_cachable_default | _PAGE_PRESENT | _PAGE_WRITE);
 
 	} else {
@@ -182,7 +199,7 @@
 	}
 }
 
-void __cpuinit cpu_cache_init(void)
+void cpu_cache_init(void)
 {
 	if (cpu_has_3k_cache) {
 		extern void __weak r3k_cache_init(void);