DM: add system reset (with RAM content kept)

This function add high level reset_vdev function. Which is
implemented to call deinit/init pairing to emulate the virtual
device reset operation.

This patch also add the system reset which keep the UOS RAM
content functionality to DM.

Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>

devicemodel/core/main.c

@@ -509,6 +509,73 @@ vm_deinit_vdevs(struct vmctx *ctx)
 	ioapic_deinit();
 }
 
+static void
+vm_reset_vdevs(struct vmctx *ctx)
+{
+	/*
+	 * The current virtual devices doesn't define virtual
+	 * device reset function. So we call vdev deinit/init
+	 * pairing to emulate the device reset operation.
+	 *
+	 * pci/ioapic deinit/init is needed because of dependency
+	 * of pci irq allocation/free.
+	 *
+	 * acpi build is necessary because irq for each vdev
+	 * could be assigned with different number after reset.
+	 */
+	atkbdc_deinit(ctx);
+	vrtc_deinit(ctx);
+
+	deinit_pci(ctx);
+	pci_irq_deinit(ctx);
+	ioapic_deinit();
+
+	atkbdc_init(ctx);
+	vrtc_init(ctx);
+
+	ioapic_init(ctx);
+	pci_irq_init(ctx);
+	init_pci(ctx);
+
+	if (acpi) {
+		acpi_build(ctx, guest_ncpus);
+	}
+}
+
+static void
+vm_system_reset(struct vmctx *ctx)
+{
+	int vcpu_id = 0;
+
+	/*
+	 * If we get system reset request, we don't want to exit the
+	 * vcpu_loop/vm_loop/mevent_loop. So we do:
+	 *   1. pause VM
+	 *   2. notify request done to reset ioreq state in vhm
+	 *   3. reset virtual devices
+	 *   4. load software for UOS
+	 *   5. hypercall reset vm
+	 *   6. reset suspend mode to VM_SUSPEND_NONE
+	 */
+
+	vm_pause(ctx);
+	for (vcpu_id = 0; vcpu_id < 4; vcpu_id++) {
+		struct vhm_request *vhm_req;
+
+		vhm_req = &vhm_req_buf[vcpu_id];
+		if (vhm_req->valid &&
+			(vhm_req->processed == REQ_STATE_PROCESSING) &&
+			(vhm_req->client == ctx->ioreq_client))
+			vm_notify_request_done(ctx, vcpu_id);
+	}
+
+	vm_reset_vdevs(ctx);
+
+	acrn_sw_load(ctx);
+	vm_reset(ctx);
+	vm_set_suspend_mode(VM_SUSPEND_NONE);
+}
+
 static void
 vm_loop(struct vmctx *ctx)
 {
@@ -521,19 +588,23 @@ vm_loop(struct vmctx *ctx)
 	assert(error == 0);
 
 	while (1) {
-		int vcpu;
+		int vcpu_id;
 		struct vhm_request *vhm_req;
 
 		error = vm_attach_ioreq_client(ctx);
 		if (error)
 			break;
 
-		for (vcpu = 0; vcpu < 4; vcpu++) {
-			vhm_req = &vhm_req_buf[vcpu];
+		for (vcpu_id = 0; vcpu_id < 4; vcpu_id++) {
+			vhm_req = &vhm_req_buf[vcpu_id];
 			if (vhm_req->valid
 				&& (vhm_req->processed == REQ_STATE_PROCESSING)
 				&& (vhm_req->client == ctx->ioreq_client))
-				handle_vmexit(ctx, vhm_req, vcpu);
+				handle_vmexit(ctx, vhm_req, vcpu_id);
+		}
+
+		if (VM_SUSPEND_SYSTEM_RESET == vm_get_suspend_mode()) {
+			vm_system_reset(ctx);
 		}
 	}
 	quit_vm_loop = 0;

devicemodel/hw/pci/core.c

@@ -827,6 +827,7 @@ pci_emul_deinit(struct vmctx *ctx, struct pci_vdev_ops *ops, int bus, int slot,
 		free(fi->fi_param);
 
 	if (fi->fi_devi) {
+		pci_lintr_release(fi->fi_devi);
 		pci_emul_free_bars(fi->fi_devi);
 		free(fi->fi_devi);
 	}
@@ -1621,6 +1622,25 @@ pci_lintr_request(struct pci_vdev *dev)
 	pci_set_cfgdata8(dev, PCIR_INTPIN, bestpin + 1);
 }
 
+void
+pci_lintr_release(struct pci_vdev *dev)
+{
+	struct businfo *bi;
+	struct slotinfo *si;
+	int pin;
+
+	bi = pci_businfo[dev->bus];
+	assert(bi != NULL);
+
+	si = &bi->slotinfo[dev->slot];
+
+	for (pin = 1; pin < 4; pin++) {
+		si->si_intpins[pin].ii_count = 0;
+		si->si_intpins[pin].ii_pirq_pin = 0;
+		si->si_intpins[pin].ii_ioapic_irq = 0;
+	}
+}
+
 static void
 pci_lintr_route(struct pci_vdev *dev)
 {

devicemodel/include/pci_core.h

@@ -257,6 +257,7 @@ void	pci_generate_msix(struct pci_vdev *pi, int msgnum);
 void	pci_lintr_assert(struct pci_vdev *pi);
 void	pci_lintr_deassert(struct pci_vdev *pi);
 void	pci_lintr_request(struct pci_vdev *pi);
+void	pci_lintr_release(struct pci_vdev *pi);
 int	pci_msi_enabled(struct pci_vdev *pi);
 int	pci_msix_enabled(struct pci_vdev *pi);
 int	pci_msix_table_bar(struct pci_vdev *pi);