Changeset 17aa6d1 in mainline for kernel/arch/amd64/src/boot/multiboot2.S

Timestamp:

2018-11-12T20:45:38Z (5 years ago)

Author:

Jiří Zárevúcky <zarevucky.jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

9a791eb9

Parents:

08f1a6d

Message:

Deduplicate bootstrap code

File:

• kernel/arch/amd64/src/boot/multiboot2.S (modified) (3 diffs)

kernel/arch/amd64/src/boot/multiboot2.S

@@ -34 +34 @@
 #include <arch/cpu.h>
 #include <genarch/multiboot/multiboot2.h>
-
-#define START_STACK  (BOOT_OFFSET - BOOT_STACK_SIZE)
 
 .section K_TEXT_START, "ax"
@@ -80 +78 @@
                 .word MULTIBOOT2_FLAGS_REQUIRED
                 .long tag_entry_address_end - tag_entry_address_start
-                .long multiboot2_image_start
+                .long multiboot_image_start
         tag_entry_address_end:
 
@@ -122 +120 @@
         tag_terminator_end:
 multiboot2_header_end:
-
-SYMBOL(multiboot2_image_start)
-        cli
-        cld
-
-        /* Initialize stack pointer */
-        movl $START_STACK, %esp
-
-        /*
-         * Initialize Global Descriptor Table and
-         * Interrupt Descriptor Table registers
-         */
-        lgdtl bootstrap_gdtr
-        lidtl bootstrap_idtr
-
-        /* Kernel data + stack */
-        movw $GDT_SELECTOR(KDATA_DES), %cx
-        movw %cx, %es
-        movw %cx, %ds
-        movw %cx, %ss
-
-        /*
-         * Simics seems to remove hidden part of GS on entering user mode
-         * when _visible_ part of GS does not point to user-mode segment.
-         */
-        movw $GDT_SELECTOR(UDATA_DES), %cx
-        movw %cx, %fs
-        movw %cx, %gs
-
-        jmpl $GDT_SELECTOR(KTEXT32_DES), $multiboot2_meeting_point
-        multiboot2_meeting_point:
-
-        /*
-         * Protected 32-bit. We want to reuse the code-seg descriptor,
-         * the Default operand size must not be 1 when entering long mode.
-         */
-
-        /* Save multiboot arguments */
-        movl %eax, multiboot_eax
-        movl %ebx, multiboot_ebx
-
-        movl $(INTEL_CPUID_EXTENDED), %eax
-        cpuid
-        cmp $(INTEL_CPUID_EXTENDED), %eax
-        ja extended_cpuid_supported
-
-                jmp pm_error_halt
-
-        extended_cpuid_supported:
-
-        movl $(AMD_CPUID_EXTENDED), %eax
-        cpuid
-        bt $(AMD_EXT_LONG_MODE), %edx
-        jc long_mode_supported
-
-                jmp pm_error_halt
-
-        long_mode_supported:
-
-        bt $(AMD_EXT_NOEXECUTE), %edx
-        jc noexecute_supported
-
-                jmp pm_error_halt
-
-        noexecute_supported:
-
-        movl $(INTEL_CPUID_STANDARD), %eax
-        cpuid
-        bt $(INTEL_FXSAVE), %edx
-        jc fx_supported
-
-                jmp pm_error_halt
-
-        fx_supported:
-
-        bt $(INTEL_SSE2), %edx
-        jc sse2_supported
-
-                jmp pm_error_halt
-
-        sse2_supported:
-
-        /*
-         * Enable 64-bit page translation entries - CR4.PAE = 1.
-         * Paging is not enabled until after long mode is enabled.
-         */
-
-        movl %cr4, %eax
-        orl $CR4_PAE, %eax
-        movl %eax, %cr4
-
-        /* Set up paging tables */
-        leal ptl_0, %eax
-        movl %eax, %cr3
-
-        /* Enable long mode */
-        movl $AMD_MSR_EFER, %ecx
-        rdmsr                     /* read EFER */
-        orl $AMD_LME, %eax        /* set LME = 1 */
-        wrmsr
-
-        /* Enable paging to activate long mode (set CR0.PG = 1) */
-        movl %cr0, %eax
-        orl $CR0_PG, %eax
-        movl %eax, %cr0
-
-        /* At this point we are in compatibility mode */
-        jmpl $GDT_SELECTOR(KTEXT_DES), $start64
-
-pm_error_halt:
-        cli
-        hlt1:
-                hlt
-                jmp hlt1
-
-.code64
-
-start64:
-
-        /*
-         * Long mode.
-         */
-
-        movq $(PA2KA(START_STACK)), %rsp
-
-        /* Create the first stack frame */
-        pushq $0
-        movq %rsp, %rbp
-
-        /* Call amd64_pre_main(multiboot_eax, multiboot_ebx) */
-        movl multiboot_eax, %edi
-        movl multiboot_ebx, %esi
-
-#ifdef MEMORY_MODEL_large
-        movabsq $amd64_pre_main, %rax
-        callq *%rax
-#else
-        callq amd64_pre_main
-#endif
-
-        /* Call main_bsp() */
-#ifdef MEMORY_MODEL_large
-        movabsq $main_bsp, %rax
-        callq *%rax
-#else
-        callq main_bsp
-#endif
-
-        /* Not reached */
-        cli
-        hlt0:
-                hlt
-                jmp hlt0