dm: pm: add s3 support for an ovmf-booted User VM

For ovmf-booted User VM, we should set CMOS shutdown status register
(index 0xF) as S3_resume(0xFE). So ovmf will read it and start S3 resume
at POST entry.

And ovmf will read waking vector from FACS table and transfer control to
guest.

Tracked-On: #8624
Signed-off-by: Haiwei Li <haiwei.li@intel.com>

devicemodel/core/main.c

@@ -102,6 +102,7 @@ bool vtpm2;
 bool is_winvm;
 bool skip_pci_mem64bar_workaround = false;
 bool gfx_ui = false;
+bool ovmf_loaded = false;
 
 static int guest_ncpus;
 static int virtio_msix = 1;
@@ -752,6 +753,8 @@ vm_suspend_resume(struct vmctx *ctx)
 	 *   6. hypercall restart vm
 	 */
 	vm_pause(ctx);
+	if (ovmf_loaded)
+		vrtc_suspend(ctx);
 
 	vm_clear_ioreq(ctx);
 	vm_stop_watchdog(ctx);
@@ -1016,6 +1019,7 @@ main(int argc, char *argv[])
 		case CMD_OPT_OVMF:
 			if (!vsbl_file_name && acrn_parse_ovmf(optarg) != 0)
 				errx(EX_USAGE, "invalid ovmf param %s", optarg);
+			ovmf_loaded = true;
 			skip_pci_mem64bar_workaround = true;
 			break;
 		case CMD_OPT_IASL:

devicemodel/core/sw_load_common.c

@@ -297,7 +297,7 @@ acrn_sw_load(struct vmctx *ctx)
 {
 	if (vsbl_file_name)
 		return acrn_sw_load_vsbl(ctx);
-	else if ((ovmf_file_name != NULL) ^ (ovmf_code_file_name && ovmf_vars_file_name))
+	else if (ovmf_loaded)
 		return acrn_sw_load_ovmf(ctx);
 	else if (kernel_file_name)
 		return acrn_sw_load_bzimage(ctx);

devicemodel/hw/platform/rtc.c

@@ -1040,6 +1040,17 @@ vrtc_set_time(struct vrtc *vrtc, time_t secs)
 	return error;
 }
 
+/* set CMOS shutdown status register (index 0xF) as S3_resume(0xFE)
+ * BIOS will read it and start S3 resume at POST Entry
+ */
+void vrtc_suspend(struct vmctx *ctx)
+{
+	struct vrtc *vrtc = ctx->vrtc;
+	struct rtcdev *rtc = &vrtc->rtcdev;
+
+	*((uint8_t *)rtc + 0xF) = 0xFE;
+}
+
 int
 vrtc_init(struct vmctx *ctx)
 {

devicemodel/include/dm.h

@@ -53,6 +53,7 @@ extern bool pt_tpm2;
 extern bool ssram;
 extern bool vtpm2;
 extern bool is_winvm;
+extern bool ovmf_loaded;
 
 enum acrn_thread_prio {
 	PRIO_VCPU = PRIO_MIN,

devicemodel/include/rtc.h

@@ -43,6 +43,7 @@ struct vrtc;
 struct vmctx;
 
 int vrtc_init(struct vmctx *ctx);
+void vrtc_suspend(struct vmctx *ctx);
 void vrtc_enable_localtime(int l_time);
 void vrtc_deinit(struct vmctx *ctx);
 int vrtc_set_time(struct vrtc *vrtc, time_t secs);