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-rw-r--r--arch/x86/kernel/head.c71
1 files changed, 0 insertions, 71 deletions
diff --git a/arch/x86/kernel/head.c b/arch/x86/kernel/head.c
deleted file mode 100644
index 992f442ca155..000000000000
--- a/arch/x86/kernel/head.c
+++ /dev/null
@@ -1,71 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/memblock.h>
-
-#include <asm/setup.h>
-#include <asm/bios_ebda.h>
-
-/*
- * The BIOS places the EBDA/XBDA at the top of conventional
- * memory, and usually decreases the reported amount of
- * conventional memory (int 0x12) too. This also contains a
- * workaround for Dell systems that neglect to reserve EBDA.
- * The same workaround also avoids a problem with the AMD768MPX
- * chipset: reserve a page before VGA to prevent PCI prefetch
- * into it (errata #56). Usually the page is reserved anyways,
- * unless you have no PS/2 mouse plugged in.
- *
- * This functions is deliberately very conservative. Losing
- * memory in the bottom megabyte is rarely a problem, as long
- * as we have enough memory to install the trampoline. Using
- * memory that is in use by the BIOS or by some DMA device
- * the BIOS didn't shut down *is* a big problem.
- */
-
-#define BIOS_LOWMEM_KILOBYTES 0x413
-#define LOWMEM_CAP 0x9f000U /* Absolute maximum */
-#define INSANE_CUTOFF 0x20000U /* Less than this = insane */
-
-void __init reserve_ebda_region(void)
-{
- unsigned int lowmem, ebda_addr;
-
- /*
- * To determine the position of the EBDA and the
- * end of conventional memory, we need to look at
- * the BIOS data area. In a paravirtual environment
- * that area is absent. We'll just have to assume
- * that the paravirt case can handle memory setup
- * correctly, without our help.
- */
- if (paravirt_enabled())
- return;
-
- /* end of low (conventional) memory */
- lowmem = *(unsigned short *)__va(BIOS_LOWMEM_KILOBYTES);
- lowmem <<= 10;
-
- /* start of EBDA area */
- ebda_addr = get_bios_ebda();
-
- /*
- * Note: some old Dells seem to need 4k EBDA without
- * reporting so, so just consider the memory above 0x9f000
- * to be off limits (bugzilla 2990).
- */
-
- /* If the EBDA address is below 128K, assume it is bogus */
- if (ebda_addr < INSANE_CUTOFF)
- ebda_addr = LOWMEM_CAP;
-
- /* If lowmem is less than 128K, assume it is bogus */
- if (lowmem < INSANE_CUTOFF)
- lowmem = LOWMEM_CAP;
-
- /* Use the lower of the lowmem and EBDA markers as the cutoff */
- lowmem = min(lowmem, ebda_addr);
- lowmem = min(lowmem, LOWMEM_CAP); /* Absolute cap */
-
- /* reserve all memory between lowmem and the 1MB mark */
- memblock_reserve(lowmem, 0x100000 - lowmem);
-}