[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/xtensa/mm/highmem.c b/src/kernel/linux/v4.14/arch/xtensa/mm/highmem.c
new file mode 100644
index 0000000..184cead
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/xtensa/mm/highmem.c
@@ -0,0 +1,95 @@
+/*
+ * High memory support for Xtensa architecture
+ *
+ * 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) 2014 Cadence Design Systems Inc.
+ */
+
+#include <linux/export.h>
+#include <linux/highmem.h>
+#include <asm/tlbflush.h>
+
+static pte_t *kmap_pte;
+
+#if DCACHE_WAY_SIZE > PAGE_SIZE
+unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
+wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
+
+static void __init kmap_waitqueues_init(void)
+{
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(pkmap_map_wait_arr); ++i)
+ init_waitqueue_head(pkmap_map_wait_arr + i);
+}
+#else
+static inline void kmap_waitqueues_init(void)
+{
+}
+#endif
+
+static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
+{
+ return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +
+ color;
+}
+
+void *kmap_atomic(struct page *page)
+{
+ enum fixed_addresses idx;
+ unsigned long vaddr;
+
+ preempt_disable();
+ pagefault_disable();
+ if (!PageHighMem(page))
+ return page_address(page);
+
+ idx = kmap_idx(kmap_atomic_idx_push(),
+ DCACHE_ALIAS(page_to_phys(page)));
+ vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+ BUG_ON(!pte_none(*(kmap_pte + idx)));
+#endif
+ set_pte(kmap_pte + idx, mk_pte(page, PAGE_KERNEL_EXEC));
+
+ return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+ if (kvaddr >= (void *)FIXADDR_START &&
+ kvaddr < (void *)FIXADDR_TOP) {
+ int idx = kmap_idx(kmap_atomic_idx(),
+ DCACHE_ALIAS((unsigned long)kvaddr));
+
+ /*
+ * Force other mappings to Oops if they'll try to access this
+ * pte without first remap it. Keeping stale mappings around
+ * is a bad idea also, in case the page changes cacheability
+ * attributes or becomes a protected page in a hypervisor.
+ */
+ pte_clear(&init_mm, kvaddr, kmap_pte + idx);
+ local_flush_tlb_kernel_range((unsigned long)kvaddr,
+ (unsigned long)kvaddr + PAGE_SIZE);
+
+ kmap_atomic_idx_pop();
+ }
+
+ pagefault_enable();
+ preempt_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
+
+void __init kmap_init(void)
+{
+ unsigned long kmap_vstart;
+
+ /* cache the first kmap pte */
+ kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+ kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+ kmap_waitqueues_init();
+}