xref: /linux/arch/x86/include/asm/gart.h (revision cbac924200b838cfb8d8b1415113d788089dc50b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_GART_H
3 #define _ASM_X86_GART_H
4 
5 #include <asm/e820/api.h>
6 
7 extern void set_up_gart_resume(u32, u32);
8 
9 extern int fallback_aper_order;
10 extern int fallback_aper_force;
11 extern int fix_aperture;
12 
13 /* PTE bits. */
14 #define GPTE_VALID	1
15 #define GPTE_COHERENT	2
16 
17 /* Aperture control register bits. */
18 #define GARTEN		(1<<0)
19 #define DISGARTCPU	(1<<4)
20 #define DISGARTIO	(1<<5)
21 #define DISTLBWALKPRB	(1<<6)
22 
23 /* GART cache control register bits. */
24 #define INVGART		(1<<0)
25 #define GARTPTEERR	(1<<1)
26 
27 /* K8 On-cpu GART registers */
28 #define AMD64_GARTAPERTURECTL	0x90
29 #define AMD64_GARTAPERTUREBASE	0x94
30 #define AMD64_GARTTABLEBASE	0x98
31 #define AMD64_GARTCACHECTL	0x9c
32 
33 #ifdef CONFIG_GART_IOMMU
34 extern int gart_iommu_aperture;
35 extern int gart_iommu_aperture_allowed;
36 extern int gart_iommu_aperture_disabled;
37 
38 extern void early_gart_iommu_check(void);
39 extern int gart_iommu_init(void);
40 extern void __init gart_parse_options(char *);
41 extern int gart_iommu_hole_init(void);
42 
43 #else
44 #define gart_iommu_aperture            0
45 #define gart_iommu_aperture_allowed    0
46 #define gart_iommu_aperture_disabled   1
47 
48 static inline void early_gart_iommu_check(void)
49 {
50 }
51 static inline void gart_parse_options(char *options)
52 {
53 }
54 static inline int gart_iommu_hole_init(void)
55 {
56 	return -ENODEV;
57 }
58 #endif
59 
60 extern int agp_amd64_init(void);
61 
62 static inline void gart_set_size_and_enable(struct pci_dev *dev, u32 order)
63 {
64 	u32 ctl;
65 
66 	/*
67 	 * Don't enable translation but enable GART IO and CPU accesses.
68 	 * Also, set DISTLBWALKPRB since GART tables memory is UC.
69 	 */
70 	ctl = order << 1;
71 
72 	pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
73 }
74 
75 static inline void enable_gart_translation(struct pci_dev *dev, u64 addr)
76 {
77 	u32 tmp, ctl;
78 
79 	/* address of the mappings table */
80 	addr >>= 12;
81 	tmp = (u32) addr<<4;
82 	tmp &= ~0xf;
83 	pci_write_config_dword(dev, AMD64_GARTTABLEBASE, tmp);
84 
85 	/* Enable GART translation for this hammer. */
86 	pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &ctl);
87 	ctl |= GARTEN | DISTLBWALKPRB;
88 	ctl &= ~(DISGARTCPU | DISGARTIO);
89 	pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
90 }
91 
92 static inline int aperture_valid(u64 aper_base, u32 aper_size, u32 min_size)
93 {
94 	if (!aper_base)
95 		return 0;
96 
97 	if (aper_base + aper_size > 0x100000000ULL) {
98 		printk(KERN_INFO "Aperture beyond 4GB. Ignoring.\n");
99 		return 0;
100 	}
101 	if (e820__mapped_any(aper_base, aper_base + aper_size, E820_TYPE_RAM)) {
102 		printk(KERN_INFO "Aperture pointing to e820 RAM. Ignoring.\n");
103 		return 0;
104 	}
105 	if (aper_size < min_size) {
106 		printk(KERN_INFO "Aperture too small (%d MB) than (%d MB)\n",
107 				 aper_size>>20, min_size>>20);
108 		return 0;
109 	}
110 
111 	return 1;
112 }
113 
114 #endif /* _ASM_X86_GART_H */
115