powerpc: Change memory_limit from phys_addr_t to unsigned long long

There are some device-tree nodes, whose values are of type phys_addr_t.
The phys_addr_t is variable sized based on the CONFIG_PHSY_T_64BIT.

Change these to a fixed unsigned long long for consistency.

This patch does the change only for memory_limit.

The following is a list of such variables which need the change:

 1) kernel_end, crashk_size - in arch/powerpc/kernel/machine_kexec.c

 2) (struct resource *)crashk_res.start - We could export a local static
    variable from machine_kexec.c.

Changing the above values might break the kexec-tools. So, I will
fix kexec-tools first to handle the different sized values and then change
 the above.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/include/asm/setup.h

@@ -9,7 +9,7 @@ extern void ppc_printk_progress(char *s, unsigned short hex);
 extern unsigned int rtas_data;
 extern int mem_init_done;	/* set on boot once kmalloc can be called */
 extern int init_bootmem_done;	/* set once bootmem is available */
-extern phys_addr_t memory_limit;
+extern unsigned long long memory_limit;
 extern unsigned long klimit;
 extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
 

arch/powerpc/kernel/fadump.c

@@ -289,8 +289,7 @@ int __init fadump_reserve_mem(void)
 		else
 			memory_limit = memblock_end_of_DRAM();
 		printk(KERN_INFO "Adjusted memory_limit for firmware-assisted"
-				" dump, now %#016llx\n",
-				(unsigned long long)memory_limit);
+				" dump, now %#016llx\n", memory_limit);
 	}
 	if (memory_limit)
 		memory_boundary = memory_limit;

arch/powerpc/kernel/machine_kexec.c

@@ -165,7 +165,7 @@ void __init reserve_crashkernel(void)
 	if (memory_limit && memory_limit <= crashk_res.end) {
 		memory_limit = crashk_res.end + 1;
 		printk("Adjusted memory limit for crashkernel, now 0x%llx\n",
-		       (unsigned long long)memory_limit);
+		       memory_limit);
 	}
 
 	printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "

arch/powerpc/kernel/prom.c

@@ -78,7 +78,7 @@ static int __init early_parse_mem(char *p)
 		return 1;
 
 	memory_limit = PAGE_ALIGN(memparse(p, &p));
-	DBG("memory limit = 0x%llx\n", (unsigned long long)memory_limit);
+	DBG("memory limit = 0x%llx\n", memory_limit);
 
 	return 0;
 }
@@ -661,7 +661,7 @@ void __init early_init_devtree(void *params)
 
 	/* make sure we've parsed cmdline for mem= before this */
 	if (memory_limit)
-		first_memblock_size = min(first_memblock_size, memory_limit);
+		first_memblock_size = min_t(u64, first_memblock_size, memory_limit);
 	setup_initial_memory_limit(memstart_addr, first_memblock_size);
 	/* Reserve MEMBLOCK regions used by kernel, initrd, dt, etc... */
 	memblock_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);

arch/powerpc/mm/mem.c

@@ -62,7 +62,7 @@
 
 int init_bootmem_done;
 int mem_init_done;
-phys_addr_t memory_limit;
+unsigned long long memory_limit;
 
 #ifdef CONFIG_HIGHMEM
 pte_t *kmap_pte;