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Diffstat (limited to 'arch/x86/kernel/bootflag.c')
-rw-r--r--arch/x86/kernel/bootflag.c50
1 files changed, 27 insertions, 23 deletions
diff --git a/arch/x86/kernel/bootflag.c b/arch/x86/kernel/bootflag.c
index 0b9860530a6b..30f25a75fe28 100644
--- a/arch/x86/kernel/bootflag.c
+++ b/arch/x86/kernel/bootflag.c
@@ -1,8 +1,6 @@
/*
* Implement 'Simple Boot Flag Specification 2.0'
*/
-
-
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
@@ -14,40 +12,38 @@
#include <linux/mc146818rtc.h>
-
#define SBF_RESERVED (0x78)
#define SBF_PNPOS (1<<0)
#define SBF_BOOTING (1<<1)
#define SBF_DIAG (1<<2)
#define SBF_PARITY (1<<7)
-
int sbf_port __initdata = -1; /* set via acpi_boot_init() */
-
static int __init parity(u8 v)
{
int x = 0;
int i;
-
- for(i=0;i<8;i++)
- {
- x^=(v&1);
- v>>=1;
+
+ for (i = 0; i < 8; i++) {
+ x ^= (v & 1);
+ v >>= 1;
}
+
return x;
}
static void __init sbf_write(u8 v)
{
unsigned long flags;
- if(sbf_port != -1)
- {
+
+ if (sbf_port != -1) {
v &= ~SBF_PARITY;
- if(!parity(v))
- v|=SBF_PARITY;
+ if (!parity(v))
+ v |= SBF_PARITY;
- printk(KERN_INFO "Simple Boot Flag at 0x%x set to 0x%x\n", sbf_port, v);
+ printk(KERN_INFO "Simple Boot Flag at 0x%x set to 0x%x\n",
+ sbf_port, v);
spin_lock_irqsave(&rtc_lock, flags);
CMOS_WRITE(v, sbf_port);
@@ -57,33 +53,41 @@ static void __init sbf_write(u8 v)
static u8 __init sbf_read(void)
{
- u8 v;
unsigned long flags;
- if(sbf_port == -1)
+ u8 v;
+
+ if (sbf_port == -1)
return 0;
+
spin_lock_irqsave(&rtc_lock, flags);
v = CMOS_READ(sbf_port);
spin_unlock_irqrestore(&rtc_lock, flags);
+
return v;
}
static int __init sbf_value_valid(u8 v)
{
- if(v&SBF_RESERVED) /* Reserved bits */
+ if (v & SBF_RESERVED) /* Reserved bits */
return 0;
- if(!parity(v))
+ if (!parity(v))
return 0;
+
return 1;
}
static int __init sbf_init(void)
{
u8 v;
- if(sbf_port == -1)
+
+ if (sbf_port == -1)
return 0;
+
v = sbf_read();
- if(!sbf_value_valid(v))
- printk(KERN_WARNING "Simple Boot Flag value 0x%x read from CMOS RAM was invalid\n",v);
+ if (!sbf_value_valid(v)) {
+ printk(KERN_WARNING "Simple Boot Flag value 0x%x read from "
+ "CMOS RAM was invalid\n", v);
+ }
v &= ~SBF_RESERVED;
v &= ~SBF_BOOTING;
@@ -92,7 +96,7 @@ static int __init sbf_init(void)
v |= SBF_PNPOS;
#endif
sbf_write(v);
+
return 0;
}
-
module_init(sbf_init);