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author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-10 19:14:41 -0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-06-10 19:14:41 -0400 |
commit | bec706838ec2f9c8c2b99e88a1270d7cba159b06 (patch) | |
tree | 96ec3ccbab3596dee79ef874483238853351a4f8 /arch/x86/boot/memory.c | |
parent | bb7762961d3ce745688e9050e914c1d3f980268d (diff) | |
parent | ee0736627d3347be0be2769fa7b26431f9726c9d (diff) |
Merge branch 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-setup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, setup: fix comment in the "glove box" code
x86, setup: "glove box" BIOS interrupts in the video code
x86, setup: "glove box" BIOS interrupts in the MCA code
x86, setup: "glove box" BIOS interrupts in the EDD code
x86, setup: "glove box" BIOS interrupts in the APM code
x86, setup: "glove box" BIOS interrupts in the core boot code
x86, setup: "glove box" BIOS calls -- infrastructure
Diffstat (limited to 'arch/x86/boot/memory.c')
-rw-r--r-- | arch/x86/boot/memory.c | 79 |
1 files changed, 39 insertions, 40 deletions
diff --git a/arch/x86/boot/memory.c b/arch/x86/boot/memory.c index 74b3d2ba84e9..cae3feb1035e 100644 --- a/arch/x86/boot/memory.c +++ b/arch/x86/boot/memory.c | |||
@@ -20,12 +20,16 @@ | |||
20 | static int detect_memory_e820(void) | 20 | static int detect_memory_e820(void) |
21 | { | 21 | { |
22 | int count = 0; | 22 | int count = 0; |
23 | u32 next = 0; | 23 | struct biosregs ireg, oreg; |
24 | u32 size, id, edi; | ||
25 | u8 err; | ||
26 | struct e820entry *desc = boot_params.e820_map; | 24 | struct e820entry *desc = boot_params.e820_map; |
27 | static struct e820entry buf; /* static so it is zeroed */ | 25 | static struct e820entry buf; /* static so it is zeroed */ |
28 | 26 | ||
27 | initregs(&ireg); | ||
28 | ireg.ax = 0xe820; | ||
29 | ireg.cx = sizeof buf; | ||
30 | ireg.edx = SMAP; | ||
31 | ireg.di = (size_t)&buf; | ||
32 | |||
29 | /* | 33 | /* |
30 | * Note: at least one BIOS is known which assumes that the | 34 | * Note: at least one BIOS is known which assumes that the |
31 | * buffer pointed to by one e820 call is the same one as | 35 | * buffer pointed to by one e820 call is the same one as |
@@ -41,22 +45,13 @@ static int detect_memory_e820(void) | |||
41 | */ | 45 | */ |
42 | 46 | ||
43 | do { | 47 | do { |
44 | size = sizeof buf; | 48 | intcall(0x15, &ireg, &oreg); |
45 | 49 | ireg.ebx = oreg.ebx; /* for next iteration... */ | |
46 | /* Important: %edx and %esi are clobbered by some BIOSes, | ||
47 | so they must be either used for the error output | ||
48 | or explicitly marked clobbered. Given that, assume there | ||
49 | is something out there clobbering %ebp and %edi, too. */ | ||
50 | asm("pushl %%ebp; int $0x15; popl %%ebp; setc %0" | ||
51 | : "=d" (err), "+b" (next), "=a" (id), "+c" (size), | ||
52 | "=D" (edi), "+m" (buf) | ||
53 | : "D" (&buf), "d" (SMAP), "a" (0xe820) | ||
54 | : "esi"); | ||
55 | 50 | ||
56 | /* BIOSes which terminate the chain with CF = 1 as opposed | 51 | /* BIOSes which terminate the chain with CF = 1 as opposed |
57 | to %ebx = 0 don't always report the SMAP signature on | 52 | to %ebx = 0 don't always report the SMAP signature on |
58 | the final, failing, probe. */ | 53 | the final, failing, probe. */ |
59 | if (err) | 54 | if (oreg.eflags & X86_EFLAGS_CF) |
60 | break; | 55 | break; |
61 | 56 | ||
62 | /* Some BIOSes stop returning SMAP in the middle of | 57 | /* Some BIOSes stop returning SMAP in the middle of |
@@ -64,60 +59,64 @@ static int detect_memory_e820(void) | |||
64 | screwed up the map at that point, we might have a | 59 | screwed up the map at that point, we might have a |
65 | partial map, the full map, or complete garbage, so | 60 | partial map, the full map, or complete garbage, so |
66 | just return failure. */ | 61 | just return failure. */ |
67 | if (id != SMAP) { | 62 | if (oreg.eax != SMAP) { |
68 | count = 0; | 63 | count = 0; |
69 | break; | 64 | break; |
70 | } | 65 | } |
71 | 66 | ||
72 | *desc++ = buf; | 67 | *desc++ = buf; |
73 | count++; | 68 | count++; |
74 | } while (next && count < ARRAY_SIZE(boot_params.e820_map)); | 69 | } while (ireg.ebx && count < ARRAY_SIZE(boot_params.e820_map)); |
75 | 70 | ||
76 | return boot_params.e820_entries = count; | 71 | return boot_params.e820_entries = count; |
77 | } | 72 | } |
78 | 73 | ||
79 | static int detect_memory_e801(void) | 74 | static int detect_memory_e801(void) |
80 | { | 75 | { |
81 | u16 ax, bx, cx, dx; | 76 | struct biosregs ireg, oreg; |
82 | u8 err; | ||
83 | 77 | ||
84 | bx = cx = dx = 0; | 78 | initregs(&ireg); |
85 | ax = 0xe801; | 79 | ireg.ax = 0xe801; |
86 | asm("stc; int $0x15; setc %0" | 80 | intcall(0x15, &ireg, &oreg); |
87 | : "=m" (err), "+a" (ax), "+b" (bx), "+c" (cx), "+d" (dx)); | ||
88 | 81 | ||
89 | if (err) | 82 | if (oreg.eflags & X86_EFLAGS_CF) |
90 | return -1; | 83 | return -1; |
91 | 84 | ||
92 | /* Do we really need to do this? */ | 85 | /* Do we really need to do this? */ |
93 | if (cx || dx) { | 86 | if (oreg.cx || oreg.dx) { |
94 | ax = cx; | 87 | oreg.ax = oreg.cx; |
95 | bx = dx; | 88 | oreg.bx = oreg.dx; |
96 | } | 89 | } |
97 | 90 | ||
98 | if (ax > 15*1024) | 91 | if (oreg.ax > 15*1024) { |
99 | return -1; /* Bogus! */ | 92 | return -1; /* Bogus! */ |
100 | 93 | } else if (oreg.ax == 15*1024) { | |
101 | /* This ignores memory above 16MB if we have a memory hole | 94 | boot_params.alt_mem_k = (oreg.dx << 6) + oreg.ax; |
102 | there. If someone actually finds a machine with a memory | 95 | } else { |
103 | hole at 16MB and no support for 0E820h they should probably | 96 | /* |
104 | generate a fake e820 map. */ | 97 | * This ignores memory above 16MB if we have a memory |
105 | boot_params.alt_mem_k = (ax == 15*1024) ? (dx << 6)+ax : ax; | 98 | * hole there. If someone actually finds a machine |
99 | * with a memory hole at 16MB and no support for | ||
100 | * 0E820h they should probably generate a fake e820 | ||
101 | * map. | ||
102 | */ | ||
103 | boot_params.alt_mem_k = oreg.ax; | ||
104 | } | ||
106 | 105 | ||
107 | return 0; | 106 | return 0; |
108 | } | 107 | } |
109 | 108 | ||
110 | static int detect_memory_88(void) | 109 | static int detect_memory_88(void) |
111 | { | 110 | { |
112 | u16 ax; | 111 | struct biosregs ireg, oreg; |
113 | u8 err; | ||
114 | 112 | ||
115 | ax = 0x8800; | 113 | initregs(&ireg); |
116 | asm("stc; int $0x15; setc %0" : "=bcdm" (err), "+a" (ax)); | 114 | ireg.ah = 0x88; |
115 | intcall(0x15, &ireg, &oreg); | ||
117 | 116 | ||
118 | boot_params.screen_info.ext_mem_k = ax; | 117 | boot_params.screen_info.ext_mem_k = oreg.ax; |
119 | 118 | ||
120 | return -err; | 119 | return -(oreg.eflags & X86_EFLAGS_CF); /* 0 or -1 */ |
121 | } | 120 | } |
122 | 121 | ||
123 | int detect_memory(void) | 122 | int detect_memory(void) |