1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Contains routines needed to support swiotlb for ppc.
4  *
5  * Copyright (C) 2009-2010 Freescale Semiconductor, Inc.
6  * Author: Becky Bruce
7  */
8 #include <linux/memblock.h>
9 #include <asm/machdep.h>
10 #include <asm/swiotlb.h>
11 
12 unsigned int ppc_swiotlb_enable;
13 
swiotlb_detect_4g(void)14 void __init swiotlb_detect_4g(void)
15 {
16 	if ((memblock_end_of_DRAM() - 1) > 0xffffffff)
17 		ppc_swiotlb_enable = 1;
18 }
19 
check_swiotlb_enabled(void)20 static int __init check_swiotlb_enabled(void)
21 {
22 	if (ppc_swiotlb_enable)
23 		swiotlb_print_info();
24 	else
25 		swiotlb_exit();
26 
27 	return 0;
28 }
29 subsys_initcall(check_swiotlb_enabled);
30