xref: /OK3568_Linux_fs/kernel/arch/mips/loongson2ef/common/mem.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  */
4*4882a593Smuzhiyun #include <linux/fs.h>
5*4882a593Smuzhiyun #include <linux/fcntl.h>
6*4882a593Smuzhiyun #include <linux/memblock.h>
7*4882a593Smuzhiyun #include <linux/mm.h>
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #include <asm/bootinfo.h>
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <loongson.h>
12*4882a593Smuzhiyun #include <mem.h>
13*4882a593Smuzhiyun #include <pci.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun u32 memsize, highmemsize;
17*4882a593Smuzhiyun 
prom_init_memory(void)18*4882a593Smuzhiyun void __init prom_init_memory(void)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	memblock_add(0x0, (memsize << 20));
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
23*4882a593Smuzhiyun 	{
24*4882a593Smuzhiyun 		int bit;
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun 		bit = fls(memsize + highmemsize);
27*4882a593Smuzhiyun 		if (bit != ffs(memsize + highmemsize))
28*4882a593Smuzhiyun 			bit += 20;
29*4882a593Smuzhiyun 		else
30*4882a593Smuzhiyun 			bit = bit + 20 - 1;
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 		/* set cpu window3 to map CPU to DDR: 2G -> 2G */
33*4882a593Smuzhiyun 		LOONGSON_ADDRWIN_CPUTODDR(ADDRWIN_WIN3, 0x80000000ul,
34*4882a593Smuzhiyun 					  0x80000000ul, (1 << bit));
35*4882a593Smuzhiyun 		mmiowb();
36*4882a593Smuzhiyun 	}
37*4882a593Smuzhiyun #endif /* !CONFIG_CPU_SUPPORTS_ADDRWINCFG */
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun #ifdef CONFIG_64BIT
40*4882a593Smuzhiyun 	if (highmemsize > 0)
41*4882a593Smuzhiyun 		memblock_add(LOONGSON_HIGHMEM_START, highmemsize << 20);
42*4882a593Smuzhiyun #endif /* !CONFIG_64BIT */
43*4882a593Smuzhiyun }
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun /* override of arch/mips/mm/cache.c: __uncached_access */
__uncached_access(struct file * file,unsigned long addr)46*4882a593Smuzhiyun int __uncached_access(struct file *file, unsigned long addr)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	if (file->f_flags & O_DSYNC)
49*4882a593Smuzhiyun 		return 1;
50*4882a593Smuzhiyun 
51*4882a593Smuzhiyun 	return addr >= __pa(high_memory) ||
52*4882a593Smuzhiyun 		((addr >= LOONGSON_MMIO_MEM_START) &&
53*4882a593Smuzhiyun 		 (addr < LOONGSON_MMIO_MEM_END));
54*4882a593Smuzhiyun }
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