hv: set start mode of vcpu

In current code, sos/uos bsp can only start from 64bit mode.

For sbl platform:
This patch start sos bsp from protected mode by default.
CONFIG_START_VM0_BSP_64BIT is defined to allow start sos bsp
from 64bit mode. If a config CONFIG_START_VM0_BSP_64BIT
defined in config file, then sos bsp will start from 64bit mode.
This patch start uos bsp from real mode, which needs the integration
of virtual bootloader (vsbl).

For uefi platform:
This patch sets sos bsp vcpu mode according to the uefi context.
This patch starts uos bsp from protected mode, because vsbl is not ready
to publish for uefi platform yet. After vsbl is ready, can change to
start uos bsp from real mode.

Signed-off-by: Binbin Wu <binbin.wu@intel.com>
Reviewed-by: Eddie Dong <eddie.dong@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Xu, Anthony <anthony.xu@intel.com>

Author: binbinwu1

hypervisor/arch/x86/guest/guest.c

@@ -552,6 +552,7 @@ int prepare_vm0_memmap_and_e820(struct vm *vm)
 	return 0;
 }
 
+#ifdef CONFIG_START_VM0_BSP_64BIT
 /*******************************************************************
  *         GUEST initial page table
  *
@@ -680,6 +681,7 @@ uint64_t create_guest_initial_paging(struct vm *vm)
 
 	return GUEST_INIT_PAGE_TABLE_START;
 }
+#endif
 
 /*******************************************************************
  *         GUEST initial GDT table

hypervisor/arch/x86/guest/vcpu.c

@@ -7,6 +7,11 @@
 #include <hypervisor.h>
 #include <schedule.h>
 
+#ifdef CONFIG_EFI_STUB
+#include <acrn_efi.h>
+extern struct efi_ctx* efi_ctx;
+#endif
+
 vm_sw_loader_t vm_sw_loader;
 
 /***********************************************************************
@@ -67,14 +72,16 @@ int create_vcpu(int cpu_id, struct vm *vm, struct vcpu **rtn_vcpu_handle)
 			vcpu->pcpu_id, vcpu->vm->attr.id, vcpu->vcpu_id,
 			is_vcpu_bsp(vcpu) ? "PRIMARY" : "SECONDARY");
 
-	/* Is this VCPU a VM BSP, create page hierarchy for this VM */
-	if (is_vcpu_bsp(vcpu)) {
+#ifdef CONFIG_START_VM0_BSP_64BIT
+	/* Is this VCPU a VM0 BSP, create page hierarchy for this VM */
+	if (is_vcpu_bsp(vcpu) && is_vm0(vcpu->vm)) {
 		/* Set up temporary guest page tables */
 		vm->arch_vm.guest_init_pml4 = create_guest_initial_paging(vm);
 		pr_info("VM *d VCPU %d CR3: 0x%016llx ",
 			vm->attr.id, vcpu->vcpu_id,
 			vm->arch_vm.guest_init_pml4);
 	}
+#endif
 
 	/* Allocate VMCS region for this VCPU */
 	vcpu->arch_vcpu.vmcs = alloc_page();
@@ -319,8 +326,24 @@ int prepare_vcpu(struct vm *vm, int pcpu_id)
 		/* Load VM SW */
 		if (!vm_sw_loader)
 			vm_sw_loader = general_sw_loader;
+		if (is_vm0(vcpu->vm)) {
+			vcpu->arch_vcpu.cpu_mode = CPU_MODE_PROTECTED;
+#ifdef CONFIG_EFI_STUB
+			if ((efi_ctx->efer & MSR_IA32_EFER_LMA_BIT) &&
+			    (efi_ctx->cs_ar & 0x2000))
+				vcpu->arch_vcpu.cpu_mode = CPU_MODE_64BIT;
+#elif CONFIG_START_VM0_BSP_64BIT
+			vcpu->arch_vcpu.cpu_mode = CPU_MODE_64BIT;
+#endif
+		} else {
+#ifdef CONFIG_EFI_STUB
+			/* currently non-vm0 will boot kernel directly */
+			vcpu->arch_vcpu.cpu_mode = CPU_MODE_PROTECTED;
+#else
+			vcpu->arch_vcpu.cpu_mode = CPU_MODE_REAL;
+#endif
+		}
 		vm_sw_loader(vm, vcpu);
-		vcpu->arch_vcpu.cpu_mode = CPU_MODE_64BIT;
 	} else {
 		vcpu->arch_vcpu.cpu_mode = CPU_MODE_REAL;
 	}

hypervisor/arch/x86/vmx.c

@@ -657,6 +657,7 @@ static void init_guest_state(struct vcpu *vcpu)
 		limit = 0xffff;
 
 	} else if (vcpu_mode == CPU_MODE_PROTECTED) {
+		/* Linear data segment in guest init gdt */
 		es = ss = ds = fs = gs = 0x18;
 		limit = 0xffffffff;
 	} else if (vcpu_mode == CPU_MODE_64BIT) {

hypervisor/common/vm_load.c

@@ -122,8 +122,10 @@ int general_sw_loader(struct vm *vm, struct vcpu *vcpu)
 	zeropage = (struct zero_page *)
 			vm->sw.kernel_info.kernel_src_addr;
 	kernel_entry_offset = (zeropage->hdr.setup_sects + 1) * 512;
-	/* 64bit entry is the 512bytes after the start */
-	kernel_entry_offset += 512;
+	if (vcpu->arch_vcpu.cpu_mode == CPU_MODE_64BIT)
+		/* 64bit entry is the 512bytes after the start */
+		kernel_entry_offset += 512;
+
 	vm->sw.kernel_info.kernel_entry_addr =
 		(void *)((unsigned long)vm->sw.kernel_info.kernel_load_addr
 			+ kernel_entry_offset);