[U-Boot] [PATCH v2 36/47] x86: Add an enum for some commonly-used GDT bits
Simon Glass
sjg at chromium.org
Fri Jul 31 17:31:53 CEST 2015
Rather than add these as open-coded values, create an enum with the commonly
used flags.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
Changes in v2:
- Add descriptor bits for the base and limit
- Rename GDT_4GB to GDT_4KB
arch/x86/include/asm/cpu.h | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index 08284ee..5b89139 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -27,6 +27,24 @@ enum {
X86_VENDOR_UNKNOWN = 0xff
};
+/* Global descriptor table (GDT) bits */
+enum {
+ GDT_4KB = 1ULL << 55,
+ GDT_32BIT = 1ULL << 54,
+ GDT_LONG = 1ULL << 53,
+ GDT_PRESENT = 1ULL << 47,
+ GDT_NOTSYS = 1ULL << 44,
+ GDT_CODE = 1ULL << 43,
+ GDT_LIMIT_LOW_SHIFT = 0,
+ GDT_LIMIT_LOW_MASK = 0xffff,
+ GDT_LIMIT_HIGH_SHIFT = 48,
+ GDT_LIMIT_HIGH_MASK = 0xf,
+ GDT_BASE_LOW_SHIFT = 16,
+ GDT_BASE_LOW_MASK = 0xffff,
+ GDT_BASE_HIGH_SHIFT = 56,
+ GDT_BASE_HIGH_MASK = 0xf,
+};
+
struct cpuid_result {
uint32_t eax;
uint32_t ebx;
--
2.5.0.rc2.392.g76e840b
More information about the U-Boot
mailing list