1 files changed, 332 insertions, 0 deletions
diff --git a/arch/sparc/mm/init_32.c b/arch/sparc/mm/init_32.c
new file mode 100644
index 0000000000..d96a14ffce
--- /dev/null
+++ b/arch/sparc/mm/init_32.c
@@ -0,0 +1,332 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/arch/sparc/mm/init.c
+ *
+ *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ *  Copyright (C) 1995 Eddie C. Dost (ecd@skynet.be)
+ *  Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ *  Copyright (C) 2000 Anton Blanchard (anton@samba.org)
+ */
+
+#include <linux/module.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/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/initrd.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/pagemap.h>
+#include <linux/poison.h>
+#include <linux/gfp.h>
+
+#include <asm/sections.h>
+#include <asm/page.h>
+#include <asm/vaddrs.h>
+#include <asm/setup.h>
+#include <asm/tlb.h>
+#include <asm/prom.h>
+#include <asm/leon.h>
+
+#include "mm_32.h"
+
+static unsigned long *sparc_valid_addr_bitmap;
+
+unsigned long phys_base;
+EXPORT_SYMBOL(phys_base);
+
+unsigned long pfn_base;
+EXPORT_SYMBOL(pfn_base);
+
+struct sparc_phys_banks sp_banks[SPARC_PHYS_BANKS+1];
+
+/* Initial ramdisk setup */
+extern unsigned int sparc_ramdisk_image;
+extern unsigned int sparc_ramdisk_size;
+
+unsigned long highstart_pfn, highend_pfn;
+
+unsigned long last_valid_pfn;
+
+unsigned long calc_highpages(void)
+{
+	int i;
+	int nr = 0;
+
+	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
+		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
+		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
+
+		if (end_pfn <= max_low_pfn)
+			continue;
+
+		if (start_pfn < max_low_pfn)
+			start_pfn = max_low_pfn;
+
+		nr += end_pfn - start_pfn;
+	}
+
+	return nr;
+}
+
+static unsigned long calc_max_low_pfn(void)
+{
+	int i;
+	unsigned long tmp = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
+	unsigned long curr_pfn, last_pfn;
+
+	last_pfn = (sp_banks[0].base_addr + sp_banks[0].num_bytes) >> PAGE_SHIFT;
+	for (i = 1; sp_banks[i].num_bytes != 0; i++) {
+		curr_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
+
+		if (curr_pfn >= tmp) {
+			if (last_pfn < tmp)
+				tmp = last_pfn;
+			break;
+		}
+
+		last_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
+	}
+
+	return tmp;
+}
+
+static void __init find_ramdisk(unsigned long end_of_phys_memory)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	unsigned long size;
+
+	/* Now have to check initial ramdisk, so that it won't pass
+	 * the end of memory
+	 */
+	if (sparc_ramdisk_image) {
+		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
+			sparc_ramdisk_image -= KERNBASE;
+		initrd_start = sparc_ramdisk_image + phys_base;
+		initrd_end = initrd_start + sparc_ramdisk_size;
+		if (initrd_end > end_of_phys_memory) {
+			printk(KERN_CRIT "initrd extends beyond end of memory "
+			       "(0x%016lx > 0x%016lx)\ndisabling initrd\n",
+			       initrd_end, end_of_phys_memory);
+			initrd_start = 0;
+		} else {
+			/* Reserve the initrd image area. */
+			size = initrd_end - initrd_start;
+			memblock_reserve(initrd_start, size);
+
+			initrd_start = (initrd_start - phys_base) + PAGE_OFFSET;
+			initrd_end = (initrd_end - phys_base) + PAGE_OFFSET;
+		}
+	}
+#endif
+}
+
+unsigned long __init bootmem_init(unsigned long *pages_avail)
+{
+	unsigned long start_pfn, bytes_avail, size;
+	unsigned long end_of_phys_memory = 0;
+	unsigned long high_pages = 0;
+	int i;
+
+	memblock_set_bottom_up(true);
+	memblock_allow_resize();
+
+	bytes_avail = 0UL;
+	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
+		end_of_phys_memory = sp_banks[i].base_addr +
+			sp_banks[i].num_bytes;
+		bytes_avail += sp_banks[i].num_bytes;
+		if (cmdline_memory_size) {
+			if (bytes_avail > cmdline_memory_size) {
+				unsigned long slack = bytes_avail - cmdline_memory_size;
+
+				bytes_avail -= slack;
+				end_of_phys_memory -= slack;
+
+				sp_banks[i].num_bytes -= slack;
+				if (sp_banks[i].num_bytes == 0) {
+					sp_banks[i].base_addr = 0xdeadbeef;
+				} else {
+					memblock_add(sp_banks[i].base_addr,
+						     sp_banks[i].num_bytes);
+					sp_banks[i+1].num_bytes = 0;
+					sp_banks[i+1].base_addr = 0xdeadbeef;
+				}
+				break;
+			}
+		}
+		memblock_add(sp_banks[i].base_addr, sp_banks[i].num_bytes);
+	}
+
+	/* Start with page aligned address of last symbol in kernel
+	 * image.
+	 */
+	start_pfn  = (unsigned long)__pa(PAGE_ALIGN((unsigned long) &_end));
+
+	/* Now shift down to get the real physical page frame number. */
+	start_pfn >>= PAGE_SHIFT;
+
+	max_pfn = end_of_phys_memory >> PAGE_SHIFT;
+
+	max_low_pfn = max_pfn;
+	highstart_pfn = highend_pfn = max_pfn;
+
+	if (max_low_pfn > pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT)) {
+		highstart_pfn = pfn_base + (SRMMU_MAXMEM >> PAGE_SHIFT);
+		max_low_pfn = calc_max_low_pfn();
+		high_pages = calc_highpages();
+		printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
+		    high_pages >> (20 - PAGE_SHIFT));
+	}
+
+	find_ramdisk(end_of_phys_memory);
+
+	/* Reserve the kernel text/data/bss. */
+	size = (start_pfn << PAGE_SHIFT) - phys_base;
+	memblock_reserve(phys_base, size);
+	memblock_add(phys_base, size);
+
+	size = memblock_phys_mem_size() - memblock_reserved_size();
+	*pages_avail = (size >> PAGE_SHIFT) - high_pages;
+
+	/* Only allow low memory to be allocated via memblock allocation */
+	memblock_set_current_limit(max_low_pfn << PAGE_SHIFT);
+
+	return max_pfn;
+}
+
+/*
+ * paging_init() sets up the page tables: We call the MMU specific
+ * init routine based upon the Sun model type on the Sparc.
+ *
+ */
+void __init paging_init(void)
+{
+	srmmu_paging_init();
+	prom_build_devicetree();
+	of_fill_in_cpu_data();
+	device_scan();
+}
+
+static void __init taint_real_pages(void)
+{
+	int i;
+
+	for (i = 0; sp_banks[i].num_bytes; i++) {
+		unsigned long start, end;
+
+		start = sp_banks[i].base_addr;
+		end = start + sp_banks[i].num_bytes;
+
+		while (start < end) {
+			set_bit(start >> 20, sparc_valid_addr_bitmap);
+			start += PAGE_SIZE;
+		}
+	}
+}
+
+static void map_high_region(unsigned long start_pfn, unsigned long end_pfn)
+{
+	unsigned long tmp;
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+	printk("mapping high region %08lx - %08lx\n", start_pfn, end_pfn);
+#endif
+
+	for (tmp = start_pfn; tmp < end_pfn; tmp++)
+		free_highmem_page(pfn_to_page(tmp));
+}
+
+void __init mem_init(void)
+{
+	int i;
+
+	if (PKMAP_BASE+LAST_PKMAP*PAGE_SIZE >= FIXADDR_START) {
+		prom_printf("BUG: fixmap and pkmap areas overlap\n");
+		prom_printf("pkbase: 0x%lx pkend: 0x%lx fixstart 0x%lx\n",
+		       PKMAP_BASE,
+		       (unsigned long)PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
+		       FIXADDR_START);
+		prom_printf("Please mail sparclinux@vger.kernel.org.\n");
+		prom_halt();
+	}
+
+
+	/* Saves us work later. */
+	memset((void *)empty_zero_page, 0, PAGE_SIZE);
+
+	i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
+	i += 1;
+	sparc_valid_addr_bitmap = (unsigned long *)
+		memblock_alloc(i << 2, SMP_CACHE_BYTES);
+
+	if (sparc_valid_addr_bitmap == NULL) {
+		prom_printf("mem_init: Cannot alloc valid_addr_bitmap.\n");
+		prom_halt();
+	}
+	memset(sparc_valid_addr_bitmap, 0, i << 2);
+
+	taint_real_pages();
+
+	max_mapnr = last_valid_pfn - pfn_base;
+	high_memory = __va(max_low_pfn << PAGE_SHIFT);
+	memblock_free_all();
+
+	for (i = 0; sp_banks[i].num_bytes != 0; i++) {
+		unsigned long start_pfn = sp_banks[i].base_addr >> PAGE_SHIFT;
+		unsigned long end_pfn = (sp_banks[i].base_addr + sp_banks[i].num_bytes) >> PAGE_SHIFT;
+
+		if (end_pfn <= highstart_pfn)
+			continue;
+
+		if (start_pfn < highstart_pfn)
+			start_pfn = highstart_pfn;
+
+		map_high_region(start_pfn, end_pfn);
+	}
+}
+
+void sparc_flush_page_to_ram(struct page *page)
+{
+	unsigned long vaddr = (unsigned long)page_address(page);
+
+	__flush_page_to_ram(vaddr);
+}
+EXPORT_SYMBOL(sparc_flush_page_to_ram);
+
+void sparc_flush_folio_to_ram(struct folio *folio)
+{
+	unsigned long vaddr = (unsigned long)folio_address(folio);
+	unsigned int i, nr = folio_nr_pages(folio);
+
+	for (i = 0; i < nr; i++)
+		__flush_page_to_ram(vaddr + i * PAGE_SIZE);
+}
+EXPORT_SYMBOL(sparc_flush_folio_to_ram);
+
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_READONLY,
+	[VM_WRITE]					= PAGE_COPY,
+	[VM_WRITE | VM_READ]				= PAGE_COPY,
+	[VM_EXEC]					= PAGE_READONLY,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY,
+	[VM_SHARED]					= PAGE_NONE,
+	[VM_SHARED | VM_READ]				= PAGE_READONLY,
+	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC]				= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED
+};
+DECLARE_VM_GET_PAGE_PROT