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authorYinghai Lu <yhlu.kernel@gmail.com>2008-05-18 08:18:57 (GMT)
committerThomas Gleixner <tglx@linutronix.de>2008-05-25 08:55:11 (GMT)
commita4c81cf684350797939416c99effb9d3ae46bca6 (patch)
tree93f58c28e1dae637a5bb9fd6166968808f10e472 /arch/x86/kernel/head32.c
parent69c9189320c46b14e5ae3ad4b3a0d35cc63cba20 (diff)
x86: extend e820 ealy_res support 32bit
move early_res related from e820_64.c to e820.c make edba detection to be done in head32.c remove smp_alloc_memory, because we have fixed trampoline address now. Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> arch/x86/kernel/e820.c | 214 ++++++++++++++++++++++++++++++++++++ arch/x86/kernel/e820_64.c | 196 -------------------------------- arch/x86/kernel/head32.c | 76 ++++++++++++ arch/x86/kernel/setup_32.c | 109 +++--------------- arch/x86/kernel/smpboot.c | 17 -- arch/x86/kernel/trampoline.c | 2 arch/x86/mach-voyager/voyager_smp.c | 9 - include/asm-x86/e820.h | 6 + include/asm-x86/e820_64.h | 9 - include/asm-x86/smp.h | 1 arch/x86/kernel/e820.c | 214 ++++++++++++++++++++++++++++++++++++ arch/x86/kernel/e820_64.c | 196 -------------------------------- arch/x86/kernel/head32.c | 76 ++++++++++++ arch/x86/kernel/setup_32.c | 109 +++--------------- arch/x86/kernel/smpboot.c | 17 -- arch/x86/kernel/trampoline.c | 2 arch/x86/mach-voyager/voyager_smp.c | 9 - include/asm-x86/e820.h | 6 + include/asm-x86/e820_64.h | 9 - include/asm-x86/smp.h | 1 arch/x86/kernel/e820.c | 214 ++++++++++++++++++++++++++++++++++++ arch/x86/kernel/e820_64.c | 196 -------------------------------- arch/x86/kernel/head32.c | 76 ++++++++++++ arch/x86/kernel/setup_32.c | 109 +++--------------- arch/x86/kernel/smpboot.c | 17 -- arch/x86/kernel/trampoline.c | 2 arch/x86/mach-voyager/voyager_smp.c | 9 - include/asm-x86/e820.h | 6 + include/asm-x86/e820_64.h | 9 - include/asm-x86/smp.h | 1 10 files changed, 320 insertions(+), 319 deletions(-) Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/head32.c')
-rw-r--r--arch/x86/kernel/head32.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index 3db0590..c216d3c 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -8,7 +8,83 @@
#include <linux/init.h>
#include <linux/start_kernel.h>
+#include <asm/setup.h>
+#include <asm/sections.h>
+#include <asm/e820.h>
+#include <asm/bios_ebda.h>
+
+#define BIOS_LOWMEM_KILOBYTES 0x413
+
+/*
+ * 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.
+ */
+static 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();
+
+ /* Fixup: bios puts an EBDA in the top 64K segment */
+ /* of conventional memory, but does not adjust lowmem. */
+ if ((lowmem - ebda_addr) <= 0x10000)
+ lowmem = ebda_addr;
+
+ /* Fixup: bios does not report an EBDA at all. */
+ /* Some old Dells seem to need 4k anyhow (bugzilla 2990) */
+ if ((ebda_addr == 0) && (lowmem >= 0x9f000))
+ lowmem = 0x9f000;
+
+ /* Paranoia: should never happen, but... */
+ if ((lowmem == 0) || (lowmem >= 0x100000))
+ lowmem = 0x9f000;
+
+ /* reserve all memory between lowmem and the 1MB mark */
+ reserve_early(lowmem, 0x100000, "BIOS reserved");
+}
+
void __init i386_start_kernel(void)
{
+ reserve_early(__pa_symbol(&_text), __pa_symbol(&_end), "TEXT DATA BSS");
+
+#ifdef CONFIG_BLK_DEV_INITRD
+ /* Reserve INITRD */
+ if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
+ u64 ramdisk_image = boot_params.hdr.ramdisk_image;
+ u64 ramdisk_size = boot_params.hdr.ramdisk_size;
+ u64 ramdisk_end = ramdisk_image + ramdisk_size;
+ reserve_early(ramdisk_image, ramdisk_end, "RAMDISK");
+ }
+#endif
+ reserve_early(__pa_symbol(&_end), init_pg_tables_end, "INIT_PG_TABLE");
+
+ reserve_ebda_region();
+
+ /*
+ * At this point everything still needed from the boot loader
+ * or BIOS or kernel text should be early reserved or marked not
+ * RAM in e820. All other memory is free game.
+ */
+
start_kernel();
}

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