[U-Boot] [PATCH v2 4/5] x86: Move the GDT into global_data

Simon Glass sjg at chromium.org
Tue Aug 11 04:44:31 CEST 2015


Rather than keeping track of the Global Descriptor Table in its own memory
we may as well put it in global_data with everything else. As a first step,
stop using the separately allocated GDT.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
---

Changes in v2: None

 arch/x86/cpu/cpu.c                 | 9 +++++----
 arch/x86/include/asm/global_data.h | 4 +++-
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index 129777c..4f57145 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -136,9 +136,10 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries)
 	asm volatile("lgdtl %0\n" : : "m" (gdt));
 }
 
-void setup_gdt(gd_t *id, u64 *gdt_addr)
+void setup_gdt(gd_t *new_gd, u64 *gdt_addr)
 {
-	id->arch.gdt = gdt_addr;
+	gdt_addr = new_gd->arch.gdt;
+
 	/* CS: code, read/execute, 4 GB, base 0 */
 	gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
 
@@ -146,9 +147,9 @@ void setup_gdt(gd_t *id, u64 *gdt_addr)
 	gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
 
 	/* FS: data, read/write, 4 GB, base (Global Data Pointer) */
-	id->arch.gd_addr = id;
+	new_gd->arch.gd_addr = new_gd;
 	gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093,
-		     (ulong)&id->arch.gd_addr, 0xfffff);
+		     (ulong)&new_gd->arch.gd_addr, 0xfffff);
 
 	/* 16-bit CS: code, read/execute, 64 kB, base 0 */
 	gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x009b, 0, 0x0ffff);
diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index f7e3889..35148ab 100644
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -10,6 +10,8 @@
 
 #ifndef __ASSEMBLY__
 
+#include <asm/processor.h>
+
 enum pei_boot_mode_t {
 	PEI_BOOT_NONE = 0,
 	PEI_BOOT_SOFT_RESET,
@@ -44,6 +46,7 @@ struct mtrr_request {
 
 /* Architecture-specific global data */
 struct arch_global_data {
+	u64 gdt[X86_GDT_NUM_ENTRIES] __aligned(16);
 	struct global_data *gd_addr;	/* Location of Global Data */
 	uint8_t x86;			/* CPU family */
 	uint8_t x86_vendor;		/* CPU vendor */
@@ -68,7 +71,6 @@ struct arch_global_data {
 	/* MRC training data to save for the next boot */
 	char *mrc_output;
 	unsigned int mrc_output_len;
-	void *gdt;			/* Global descriptor table */
 	ulong table;			/* Table pointer from previous loader */
 };
 
-- 
2.5.0.rc2.392.g76e840b



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