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-rw-r--r--arch/arc/mm/init.c202
1 files changed, 202 insertions, 0 deletions
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c
new file mode 100644
index 0000000000..6a71b23f13
--- /dev/null
+++ b/arch/arc/mm/init.c
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/memblock.h>
+#ifdef CONFIG_BLK_DEV_INITRD
+#include <linux/initrd.h>
+#endif
+#include <linux/of_fdt.h>
+#include <linux/swap.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/arcregs.h>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
+char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
+EXPORT_SYMBOL(empty_zero_page);
+
+static const unsigned long low_mem_start = CONFIG_LINUX_RAM_BASE;
+static unsigned long low_mem_sz;
+
+#ifdef CONFIG_HIGHMEM
+static unsigned long min_high_pfn, max_high_pfn;
+static phys_addr_t high_mem_start;
+static phys_addr_t high_mem_sz;
+unsigned long arch_pfn_offset;
+EXPORT_SYMBOL(arch_pfn_offset);
+#endif
+
+long __init arc_get_mem_sz(void)
+{
+ return low_mem_sz;
+}
+
+/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
+static int __init setup_mem_sz(char *str)
+{
+ low_mem_sz = memparse(str, NULL) & PAGE_MASK;
+
+ /* early console might not be setup yet - it will show up later */
+ pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz));
+
+ return 0;
+}
+early_param("mem", setup_mem_sz);
+
+void __init early_init_dt_add_memory_arch(u64 base, u64 size)
+{
+ int in_use = 0;
+
+ if (!low_mem_sz) {
+ if (base != low_mem_start)
+ panic("CONFIG_LINUX_RAM_BASE != DT memory { }");
+
+ low_mem_sz = size;
+ in_use = 1;
+ memblock_add_node(base, size, 0, MEMBLOCK_NONE);
+ } else {
+#ifdef CONFIG_HIGHMEM
+ high_mem_start = base;
+ high_mem_sz = size;
+ in_use = 1;
+ memblock_add_node(base, size, 1, MEMBLOCK_NONE);
+ memblock_reserve(base, size);
+#endif
+ }
+
+ pr_info("Memory @ %llx [%lldM] %s\n",
+ base, TO_MB(size), !in_use ? "Not used":"");
+}
+
+/*
+ * First memory setup routine called from setup_arch()
+ * 1. setup swapper's mm @init_mm
+ * 2. Count the pages we have and setup bootmem allocator
+ * 3. zone setup
+ */
+void __init setup_arch_memory(void)
+{
+ unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
+
+ setup_initial_init_mm(_text, _etext, _edata, _end);
+
+ /* first page of system - kernel .vector starts here */
+ min_low_pfn = virt_to_pfn((void *)CONFIG_LINUX_RAM_BASE);
+
+ /* Last usable page of low mem */
+ max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz);
+
+ /*------------- bootmem allocator setup -----------------------*/
+
+ /*
+ * seed the bootmem allocator after any DT memory node parsing or
+ * "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz
+ *
+ * Only low mem is added, otherwise we have crashes when allocating
+ * mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of
+ * avail memory, ending in highmem with a > 32-bit address. However
+ * it then tries to memset it with a truncaed 32-bit handle, causing
+ * the crash
+ */
+
+ memblock_reserve(CONFIG_LINUX_LINK_BASE,
+ __pa(_end) - CONFIG_LINUX_LINK_BASE);
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ if (phys_initrd_size) {
+ memblock_reserve(phys_initrd_start, phys_initrd_size);
+ initrd_start = (unsigned long)__va(phys_initrd_start);
+ initrd_end = initrd_start + phys_initrd_size;
+ }
+#endif
+
+ early_init_fdt_reserve_self();
+ early_init_fdt_scan_reserved_mem();
+
+ memblock_dump_all();
+
+ /*----------------- node/zones setup --------------------------*/
+ max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
+
+#ifdef CONFIG_HIGHMEM
+ /*
+ * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
+ * than addresses in normal aka low memory (0x8000_0000 based).
+ * Even with PAE, the huge peripheral space hole would waste a lot of
+ * mem with single contiguous mem_map[].
+ * Thus when HIGHMEM on ARC is enabled the memory map corresponding
+ * to the hole is freed and ARC specific version of pfn_valid()
+ * handles the hole in the memory map.
+ */
+
+ min_high_pfn = PFN_DOWN(high_mem_start);
+ max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
+
+ /*
+ * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE.
+ * For HIGHMEM without PAE max_high_pfn should be less than
+ * min_low_pfn to guarantee that these two regions don't overlap.
+ * For PAE case highmem is greater than lowmem, so it is natural
+ * to use max_high_pfn.
+ *
+ * In both cases, holes should be handled by pfn_valid().
+ */
+ max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
+
+ high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
+
+ arch_pfn_offset = min(min_low_pfn, min_high_pfn);
+ kmap_init();
+
+#else /* CONFIG_HIGHMEM */
+ /* pfn_valid() uses this when FLATMEM=y and HIGHMEM=n */
+ max_mapnr = max_low_pfn - min_low_pfn;
+
+#endif /* CONFIG_HIGHMEM */
+
+ free_area_init(max_zone_pfn);
+}
+
+static void __init highmem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+ unsigned long tmp;
+
+ memblock_phys_free(high_mem_start, high_mem_sz);
+ for (tmp = min_high_pfn; tmp < max_high_pfn; tmp++)
+ free_highmem_page(pfn_to_page(tmp));
+#endif
+}
+
+/*
+ * mem_init - initializes memory
+ *
+ * Frees up bootmem
+ * Calculates and displays memory available/used
+ */
+void __init mem_init(void)
+{
+ memblock_free_all();
+ highmem_init();
+
+ BUILD_BUG_ON((PTRS_PER_PGD * sizeof(pgd_t)) > PAGE_SIZE);
+ BUILD_BUG_ON((PTRS_PER_PUD * sizeof(pud_t)) > PAGE_SIZE);
+ BUILD_BUG_ON((PTRS_PER_PMD * sizeof(pmd_t)) > PAGE_SIZE);
+ BUILD_BUG_ON((PTRS_PER_PTE * sizeof(pte_t)) > PAGE_SIZE);
+}
+
+#ifdef CONFIG_HIGHMEM
+int pfn_valid(unsigned long pfn)
+{
+ return (pfn >= min_high_pfn && pfn <= max_high_pfn) ||
+ (pfn >= min_low_pfn && pfn <= max_low_pfn);
+}
+EXPORT_SYMBOL(pfn_valid);
+#endif