diff options
Diffstat (limited to 'arch/x86/kernel/head64.c')
-rw-r--r-- | arch/x86/kernel/head64.c | 50 |
1 files changed, 0 insertions, 50 deletions
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c index e25c57b8aa84..f1773c8ee21e 100644 --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c | |||
@@ -51,56 +51,6 @@ static void __init copy_bootdata(char *real_mode_data) | |||
51 | } | 51 | } |
52 | } | 52 | } |
53 | 53 | ||
54 | #define BIOS_LOWMEM_KILOBYTES 0x413 | ||
55 | |||
56 | /* | ||
57 | * The BIOS places the EBDA/XBDA at the top of conventional | ||
58 | * memory, and usually decreases the reported amount of | ||
59 | * conventional memory (int 0x12) too. This also contains a | ||
60 | * workaround for Dell systems that neglect to reserve EBDA. | ||
61 | * The same workaround also avoids a problem with the AMD768MPX | ||
62 | * chipset: reserve a page before VGA to prevent PCI prefetch | ||
63 | * into it (errata #56). Usually the page is reserved anyways, | ||
64 | * unless you have no PS/2 mouse plugged in. | ||
65 | */ | ||
66 | static void __init reserve_ebda_region(void) | ||
67 | { | ||
68 | unsigned int lowmem, ebda_addr; | ||
69 | |||
70 | /* To determine the position of the EBDA and the */ | ||
71 | /* end of conventional memory, we need to look at */ | ||
72 | /* the BIOS data area. In a paravirtual environment */ | ||
73 | /* that area is absent. We'll just have to assume */ | ||
74 | /* that the paravirt case can handle memory setup */ | ||
75 | /* correctly, without our help. */ | ||
76 | if (paravirt_enabled()) | ||
77 | return; | ||
78 | |||
79 | /* end of low (conventional) memory */ | ||
80 | lowmem = *(unsigned short *)__va(BIOS_LOWMEM_KILOBYTES); | ||
81 | lowmem <<= 10; | ||
82 | |||
83 | /* start of EBDA area */ | ||
84 | ebda_addr = get_bios_ebda(); | ||
85 | |||
86 | /* Fixup: bios puts an EBDA in the top 64K segment */ | ||
87 | /* of conventional memory, but does not adjust lowmem. */ | ||
88 | if ((lowmem - ebda_addr) <= 0x10000) | ||
89 | lowmem = ebda_addr; | ||
90 | |||
91 | /* Fixup: bios does not report an EBDA at all. */ | ||
92 | /* Some old Dells seem to need 4k anyhow (bugzilla 2990) */ | ||
93 | if ((ebda_addr == 0) && (lowmem >= 0x9f000)) | ||
94 | lowmem = 0x9f000; | ||
95 | |||
96 | /* Paranoia: should never happen, but... */ | ||
97 | if ((lowmem == 0) || (lowmem >= 0x100000)) | ||
98 | lowmem = 0x9f000; | ||
99 | |||
100 | /* reserve all memory between lowmem and the 1MB mark */ | ||
101 | reserve_early(lowmem, 0x100000, "BIOS reserved"); | ||
102 | } | ||
103 | |||
104 | static void __init reserve_setup_data(void) | 54 | static void __init reserve_setup_data(void) |
105 | { | 55 | { |
106 | struct setup_data *data; | 56 | struct setup_data *data; |