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-rw-r--r--arch/x86/cpu/cpu.c53
-rw-r--r--arch/x86/cpu/start.S8
-rw-r--r--arch/x86/include/asm/global_data.h21
-rw-r--r--arch/x86/include/asm/processor.h1
-rw-r--r--arch/x86/include/asm/u-boot-x86.h2
-rw-r--r--arch/x86/lib/board.c56
6 files changed, 94 insertions, 47 deletions
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index 8102fb9..8c3b92c 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -90,6 +90,37 @@ static void load_gdt(const u64 *boot_gdt, u16 num_entries)
asm volatile("lgdtl %0\n" : : "m" (gdt));
}
+void init_gd(gd_t *id, u64 *gdt_addr)
+{
+ id->gd_addr = (ulong)id;
+ setup_gdt(id, gdt_addr);
+}
+
+void setup_gdt(gd_t *id, u64 *gdt_addr)
+{
+ /* CS: code, read/execute, 4 GB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
+
+ /* DS: data, read/write, 4 GB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
+
+ /* FS: data, read/write, 4 GB, base (Global Data Pointer) */
+ gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093, (ulong)id, 0xfffff);
+
+ /* 16-bit CS: code, read/execute, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x109b, 0, 0x0ffff);
+
+ /* 16-bit DS: data, read/write, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x1093, 0, 0x0ffff);
+
+ load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
+ load_ds(X86_GDT_ENTRY_32BIT_DS);
+ load_es(X86_GDT_ENTRY_32BIT_DS);
+ load_gs(X86_GDT_ENTRY_32BIT_DS);
+ load_ss(X86_GDT_ENTRY_32BIT_DS);
+ load_fs(X86_GDT_ENTRY_32BIT_FS);
+}
+
int x86_cpu_init_f(void)
{
const u32 em_rst = ~X86_CR0_EM;
@@ -117,28 +148,6 @@ int x86_cpu_init_r(void)
"movl %%eax, %%cr0\n"
"wbinvd\n" : : "i" (nw_cd_rst) : "eax");
- /*
- * There are machines which are known to not boot with the GDT
- * being 8-byte unaligned. Intel recommends 16 byte alignment
- */
- static const u64 boot_gdt[] __aligned(16) = {
- /* CS: code, read/execute, 4 GB, base 0 */
- [X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff),
- /* DS: data, read/write, 4 GB, base 0 */
- [X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff),
- /* 16-bit CS: code, read/execute, 64 kB, base 0 */
- [X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x109b, 0, 0x0ffff),
- /* 16-bit DS: data, read/write, 64 kB, base 0 */
- [X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x1093, 0, 0x0ffff),
- };
-
- load_gdt(boot_gdt, X86_GDT_NUM_ENTRIES);
- load_ds(X86_GDT_ENTRY_32BIT_DS);
- load_es(X86_GDT_ENTRY_32BIT_DS);
- load_fs(X86_GDT_ENTRY_32BIT_DS);
- load_gs(X86_GDT_ENTRY_32BIT_DS);
- load_ss(X86_GDT_ENTRY_32BIT_DS);
-
/* Initialize core interrupt and exception functionality of CPU */
cpu_init_interrupts();
return 0;
diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 69a9b2c..ee0dabe 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -31,7 +31,7 @@
#include <asm/global_data.h>
#include <asm/processor.h>
#include <asm/processor-flags.h>
-#include <generated/asm-offsets.h>
+#include <generated/generic-asm-offsets.h>
.section .text
.code32
@@ -85,6 +85,12 @@ car_init_ret:
*/
movl $CONFIG_SYS_INIT_SP_ADDR, %esp
+ /* Initialise the Global Data Pointer */
+ movl $CONFIG_SYS_INIT_GD_ADDR, %eax
+ movl %eax, %edx
+ addl $GENERATED_GBL_DATA_SIZE, %edx
+ call init_gd;
+
/* Set parameter to board_init_f() to boot flags */
xorl %eax, %eax
movw %bx, %ax
diff --git a/arch/x86/include/asm/global_data.h b/arch/x86/include/asm/global_data.h
index 05a2139..908a02c 100644
--- a/arch/x86/include/asm/global_data.h
+++ b/arch/x86/include/asm/global_data.h
@@ -36,6 +36,8 @@
#ifndef __ASSEMBLY__
typedef struct global_data {
+ /* NOTE: gd_addr MUST be first member of struct global_data! */
+ unsigned long gd_addr; /* Location of Global Data */
bd_t *bd;
unsigned long flags;
unsigned long baudrate;
@@ -51,13 +53,24 @@ typedef struct global_data {
unsigned long bus_clk;
unsigned long relocaddr; /* Start address of U-Boot in RAM */
unsigned long start_addr_sp; /* start_addr_stackpointer */
+ unsigned long gdt_addr; /* Location of GDT */
+ unsigned long new_gd_addr; /* New location of Global Data */
phys_size_t ram_size; /* RAM size */
unsigned long reset_status; /* reset status register at boot */
void **jt; /* jump table */
char env_buf[32]; /* buffer for getenv() before reloc. */
} gd_t;
-extern gd_t *gd;
+static inline gd_t *get_fs_gd_ptr(void)
+{
+ gd_t *gd_ptr;
+
+ asm volatile("fs movl 0, %0\n" : "=r" (gd_ptr));
+
+ return gd_ptr;
+}
+
+#define gd get_fs_gd_ptr()
#endif
@@ -73,12 +86,6 @@ extern gd_t *gd;
#define GD_FLG_DISABLE_CONSOLE 0x00040 /* Disable console (in & out) */
#define GD_FLG_ENV_READY 0x00080 /* Environment imported into hash table */
-#if 0
#define DECLARE_GLOBAL_DATA_PTR
-#else
-#define XTRN_DECLARE_GLOBAL_DATA_PTR extern
-#define DECLARE_GLOBAL_DATA_PTR XTRN_DECLARE_GLOBAL_DATA_PTR \
-gd_t *gd
-#endif
#endif /* __ASM_GBL_DATA_H */
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index aa8188e..6eb5180 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -33,6 +33,7 @@ enum {
X86_GDT_ENTRY_UNUSED,
X86_GDT_ENTRY_32BIT_CS,
X86_GDT_ENTRY_32BIT_DS,
+ X86_GDT_ENTRY_32BIT_FS,
X86_GDT_ENTRY_16BIT_CS,
X86_GDT_ENTRY_16BIT_DS,
X86_GDT_NUM_ENTRIES
diff --git a/arch/x86/include/asm/u-boot-x86.h b/arch/x86/include/asm/u-boot-x86.h
index c3d2277..5540d51 100644
--- a/arch/x86/include/asm/u-boot-x86.h
+++ b/arch/x86/include/asm/u-boot-x86.h
@@ -37,6 +37,8 @@ int x86_cpu_init_r(void);
int cpu_init_r(void);
int x86_cpu_init_f(void);
int cpu_init_f(void);
+void init_gd(gd_t *id, u64 *gdt_addr);
+void setup_gdt(gd_t *id, u64 *gdt_addr);
/* cpu/.../timer.c */
void timer_isr(void *);
diff --git a/arch/x86/lib/board.c b/arch/x86/lib/board.c
index 6f075b7..b64c2d3 100644
--- a/arch/x86/lib/board.c
+++ b/arch/x86/lib/board.c
@@ -42,20 +42,12 @@
#include <serial.h>
#include <asm/u-boot-x86.h>
#include <elf.h>
+#include <asm/processor.h>
#ifdef CONFIG_BITBANGMII
#include <miiphy.h>
#endif
-/*
- * Pointer to initial global data area
- *
- * Here we initialize it.
- */
-#undef XTRN_DECLARE_GLOBAL_DATA_PTR
-#define XTRN_DECLARE_GLOBAL_DATA_PTR /* empty = allocate here */
-DECLARE_GLOBAL_DATA_PTR = (gd_t *) (CONFIG_SYS_INIT_GD_ADDR);
-
/************************************************************************
* Init Utilities *
************************************************************************
@@ -128,6 +120,7 @@ static int calculate_relocation_address(void);
static int copy_uboot_to_ram(void);
static int clear_bss(void);
static int do_elf_reloc_fixups(void);
+static int copy_gd_to_ram(void);
init_fnc_t *init_sequence_f[] = {
cpu_init_f,
@@ -146,6 +139,7 @@ init_fnc_t *init_sequence_f[] = {
};
init_fnc_t *init_sequence_r[] = {
+ copy_gd_to_ram,
cpu_init_r, /* basic cpu dependent setup */
board_early_init_r, /* basic board dependent setup */
dram_init, /* configure available RAM banks */
@@ -157,8 +151,6 @@ init_fnc_t *init_sequence_r[] = {
NULL,
};
-gd_t *gd;
-
static int calculate_relocation_address(void)
{
ulong text_start = (ulong)&__text_start;
@@ -171,8 +163,18 @@ static int calculate_relocation_address(void)
* requirements
*/
- /* Stack is at top of available memory */
+ /* Global Data is at top of available memory */
dest_addr = gd->ram_size;
+ dest_addr -= GENERATED_GBL_DATA_SIZE;
+ dest_addr &= ~15;
+ gd->new_gd_addr = dest_addr;
+
+ /* GDT is below Global Data */
+ dest_addr -= X86_GDT_SIZE;
+ dest_addr &= ~15;
+ gd->gdt_addr = dest_addr;
+
+ /* Stack is below GDT */
gd->start_addr_sp = dest_addr;
/* U-Boot is below the stack */
@@ -279,6 +281,31 @@ void board_init_f_r(void)
;
}
+static int copy_gd_to_ram(void)
+{
+ gd_t *ram_gd;
+
+ /*
+ * Global data is still in temporary memory (the CPU cache).
+ * calculate_relocation_address() has set gd->new_gd_addr to
+ * where the global data lives in RAM but getting it there
+ * safely is a bit tricky due to the 'F-Segment Hack' that
+ * we need to use for x86
+ */
+ ram_gd = (gd_t *)gd->new_gd_addr;
+ memcpy((void *)ram_gd, gd, sizeof(gd_t));
+
+ /*
+ * Reload the Global Descriptor Table so FS points to the
+ * in-RAM copy of Global Data (calculate_relocation_address()
+ * has already calculated the in-RAM location of the GDT)
+ */
+ ram_gd->gd_addr = (ulong)ram_gd;
+ init_gd(ram_gd, (u64 *)gd->gdt_addr);
+
+ return 0;
+}
+
void board_init_r(gd_t *id, ulong dest_addr)
{
#if defined(CONFIG_CMD_NET)
@@ -288,15 +315,10 @@ void board_init_r(gd_t *id, ulong dest_addr)
ulong size;
#endif
static bd_t bd_data;
- static gd_t gd_data;
init_fnc_t **init_fnc_ptr;
show_boot_progress(0x21);
- /* Global data pointer is now writable */
- gd = &gd_data;
- memcpy(gd, id, sizeof(gd_t));
-
/* compiler optimization barrier needed for GCC >= 3.4 */
__asm__ __volatile__("" : : : "memory");
generated by cgit v1.1 at 2024-12-23 06:22:20 +0000