Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
new file mode 100644
index 0000000..d4c2292
--- /dev/null
+++ b/arch/csky/mm/init.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/bug.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/pagemap.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/swap.h>
+#include <linux/proc_fs.h>
+#include <linux/pfn.h>
+
+#include <asm/setup.h>
+#include <asm/cachectl.h>
+#include <asm/dma.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
+ __page_aligned_bss;
+EXPORT_SYMBOL(empty_zero_page);
+
+void __init mem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+ unsigned long tmp;
+
+ max_mapnr = highend_pfn;
+#else
+ max_mapnr = max_low_pfn;
+#endif
+ high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
+
+ memblock_free_all();
+
+#ifdef CONFIG_HIGHMEM
+ for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
+ struct page *page = pfn_to_page(tmp);
+
+ /* FIXME not sure about */
+ if (!memblock_is_reserved(tmp << PAGE_SHIFT))
+ free_highmem_page(page);
+ }
+#endif
+ mem_init_print_info(NULL);
+}
+
+extern char __init_begin[], __init_end[];
+
+void free_initmem(void)
+{
+ unsigned long addr;
+
+ addr = (unsigned long) &__init_begin;
+
+ while (addr < (unsigned long) &__init_end) {
+ ClearPageReserved(virt_to_page(addr));
+ init_page_count(virt_to_page(addr));
+ free_page(addr);
+ totalram_pages_inc();
+ addr += PAGE_SIZE;
+ }
+
+ pr_info("Freeing unused kernel memory: %dk freed\n",
+ ((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10);
+}
+
+void pgd_init(unsigned long *p)
+{
+ int i;
+
+ for (i = 0; i < PTRS_PER_PGD; i++)
+ p[i] = __pa(invalid_pte_table);
+}
+
+void __init pre_mmu_init(void)
+{
+ /*
+ * Setup page-table and enable TLB-hardrefill
+ */
+ flush_tlb_all();
+ pgd_init((unsigned long *)swapper_pg_dir);
+ TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);
+ TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir);
+
+ /* Setup page mask to 4k */
+ write_mmu_pagemask(0);
+}