--- zzzz-none-000/linux-3.10.107/arch/s390/mm/mem_detect.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/s390/mm/mem_detect.c	2021-02-04 17:41:59.000000000 +0000
@@ -6,130 +6,56 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/memblock.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
 #include <asm/ipl.h>
 #include <asm/sclp.h>
 #include <asm/setup.h>
 
 #define ADDR2G (1ULL << 31)
 
-static void find_memory_chunks(struct mem_chunk chunk[], unsigned long maxsize)
+#define CHUNK_READ_WRITE 0
+#define CHUNK_READ_ONLY  1
+
+static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
+{
+	memblock_add_range(&memblock.memory, start, size, 0, 0);
+	memblock_add_range(&memblock.physmem, start, size, 0, 0);
+}
+
+void __init detect_memory_memblock(void)
 {
 	unsigned long long memsize, rnmax, rzm;
-	unsigned long addr = 0, size;
-	int i = 0, type;
+	unsigned long addr, size;
+	int type;
 
-	rzm = sclp_get_rzm();
-	rnmax = sclp_get_rnmax();
+	rzm = sclp.rzm;
+	rnmax = sclp.rnmax;
 	memsize = rzm * rnmax;
 	if (!rzm)
 		rzm = 1ULL << 17;
-	if (sizeof(long) == 4) {
-		rzm = min(ADDR2G, rzm);
-		memsize = memsize ? min(ADDR2G, memsize) : ADDR2G;
-	}
-	if (maxsize)
-		memsize = memsize ? min((unsigned long)memsize, maxsize) : maxsize;
+	max_physmem_end = memsize;
+	addr = 0;
+	/* keep memblock lists close to the kernel */
+	memblock_set_bottom_up(true);
 	do {
 		size = 0;
 		type = tprot(addr);
 		do {
 			size += rzm;
-			if (memsize && addr + size >= memsize)
+			if (max_physmem_end && addr + size >= max_physmem_end)
 				break;
 		} while (type == tprot(addr + size));
 		if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
-			if (memsize && (addr + size > memsize))
-				size = memsize - addr;
-			chunk[i].addr = addr;
-			chunk[i].size = size;
-			chunk[i].type = type;
-			i++;
+			if (max_physmem_end && (addr + size > max_physmem_end))
+				size = max_physmem_end - addr;
+			memblock_physmem_add(addr, size);
 		}
 		addr += size;
-	} while (addr < memsize && i < MEMORY_CHUNKS);
-}
-
-/**
- * detect_memory_layout - fill mem_chunk array with memory layout data
- * @chunk: mem_chunk array to be filled
- * @maxsize: maximum address where memory detection should stop
- *
- * Fills the passed in memory chunk array with the memory layout of the
- * machine. The array must have a size of at least MEMORY_CHUNKS and will
- * be fully initialized afterwards.
- * If the maxsize paramater has a value > 0 memory detection will stop at
- * that address. It is guaranteed that all chunks have an ending address
- * that is smaller than maxsize.
- * If maxsize is 0 all memory will be detected.
- */
-void detect_memory_layout(struct mem_chunk chunk[], unsigned long maxsize)
-{
-	unsigned long flags, flags_dat, cr0;
-
-	memset(chunk, 0, MEMORY_CHUNKS * sizeof(struct mem_chunk));
-	/*
-	 * Disable IRQs, DAT and low address protection so tprot does the
-	 * right thing and we don't get scheduled away with low address
-	 * protection disabled.
-	 */
-	local_irq_save(flags);
-	flags_dat = __arch_local_irq_stnsm(0xfb);
-	/*
-	 * In case DAT was enabled, make sure chunk doesn't reside in vmalloc
-	 * space. We have disabled DAT and any access to vmalloc area will
-	 * cause an exception.
-	 * If DAT was disabled we are called from early ipl code.
-	 */
-	if (test_bit(5, &flags_dat)) {
-		if (WARN_ON_ONCE(is_vmalloc_or_module_addr(chunk)))
-			goto out;
-	}
-	__ctl_store(cr0, 0, 0);
-	__ctl_clear_bit(0, 28);
-	find_memory_chunks(chunk, maxsize);
-	__ctl_load(cr0, 0, 0);
-out:
-	__arch_local_irq_ssm(flags_dat);
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL(detect_memory_layout);
-
-/*
- * Create memory hole with given address and size.
- */
-void create_mem_hole(struct mem_chunk mem_chunk[], unsigned long addr,
-		     unsigned long size)
-{
-	int i;
-
-	for (i = 0; i < MEMORY_CHUNKS; i++) {
-		struct mem_chunk *chunk = &mem_chunk[i];
-
-		if (chunk->size == 0)
-			continue;
-		if (addr > chunk->addr + chunk->size)
-			continue;
-		if (addr + size <= chunk->addr)
-			continue;
-		/* Split */
-		if ((addr > chunk->addr) &&
-		    (addr + size < chunk->addr + chunk->size)) {
-			struct mem_chunk *new = chunk + 1;
-
-			memmove(new, chunk, (MEMORY_CHUNKS-i-1) * sizeof(*new));
-			new->addr = addr + size;
-			new->size = chunk->addr + chunk->size - new->addr;
-			chunk->size = addr - chunk->addr;
-			continue;
-		} else if ((addr <= chunk->addr) &&
-			   (addr + size >= chunk->addr + chunk->size)) {
-			memmove(chunk, chunk + 1, (MEMORY_CHUNKS-i-1) * sizeof(*chunk));
-			memset(&mem_chunk[MEMORY_CHUNKS-1], 0, sizeof(*chunk));
-		} else if (addr + size < chunk->addr + chunk->size) {
-			chunk->size =  chunk->addr + chunk->size - addr - size;
-			chunk->addr = addr + size;
-		} else if (addr > chunk->addr) {
-			chunk->size = addr - chunk->addr;
-		}
-	}
+	} while (addr < max_physmem_end);
+	memblock_set_bottom_up(false);
+	if (!max_physmem_end)
+		max_physmem_end = memblock_end_of_DRAM();
 }