kvm tools: Add VESA device

Add a simple VESA device which simply moves a framebuffer
from guest kernel to a VNC server.

VESA device PCI code is very similar to virtio-* PCI code.

Signed-off-by: John Floren <john@jfloren.net>
[ turning code into patches and cleanup ]
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

hw/vesa.c

@@ -0,0 +1,107 @@
+#include "kvm/vesa.h"
+#include "kvm/ioport.h"
+#include "kvm/util.h"
+#include "kvm/kvm.h"
+#include "kvm/pci.h"
+#include "kvm/kvm-cpu.h"
+#include "kvm/irq.h"
+#include "kvm/virtio-pci-dev.h"
+
+#include <rfb/rfb.h>
+
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <inttypes.h>
+#include <unistd.h>
+
+#define VESA_QUEUE_SIZE		128
+#define VESA_IRQ		14
+
+/*
+ * This "6000" value is pretty much the result of experimentation
+ * It seems that around this value, things update pretty smoothly
+ */
+#define VESA_UPDATE_TIME	6000
+
+u8 videomem[VESA_MEM_SIZE];
+
+static bool vesa_pci_io_in(struct kvm *kvm, u16 port, void *data, int size, u32 count)
+{
+	printf("vesa in port=%u\n", port);
+	return true;
+}
+
+static bool vesa_pci_io_out(struct kvm *kvm, u16 port, void *data, int size, u32 count)
+{
+	printf("vesa out port=%u\n", port);
+	return true;
+}
+
+static struct ioport_operations vesa_io_ops = {
+	.io_in	= vesa_pci_io_in,
+	.io_out	= vesa_pci_io_out,
+};
+
+static struct pci_device_header vesa_pci_device = {
+	.vendor_id		= PCI_VENDOR_ID_REDHAT_QUMRANET,
+	.device_id		= PCI_DEVICE_ID_VESA,
+	.header_type		= PCI_HEADER_TYPE_NORMAL,
+	.revision_id		= 0,
+	.class			= 0x030000,
+	.subsys_vendor_id	= PCI_SUBSYSTEM_VENDOR_ID_REDHAT_QUMRANET,
+	.subsys_id		= PCI_SUBSYSTEM_ID_VESA,
+	.bar[0]			= IOPORT_VESA | PCI_BASE_ADDRESS_SPACE_IO,
+	.bar[1]			= VESA_MEM_ADDR | PCI_BASE_ADDRESS_SPACE_MEMORY,
+};
+
+
+void vesa_mmio_callback(u64 addr, u8 *data, u32 len, u8 is_write)
+{
+	if (is_write)
+		memcpy(&videomem[addr - VESA_MEM_ADDR], data, len);
+
+	return;
+}
+
+void vesa__init(struct kvm *kvm)
+{
+	u8 dev, line, pin;
+	pthread_t thread;
+
+	if (irq__register_device(PCI_DEVICE_ID_VESA, &dev, &pin, &line) < 0)
+		return;
+
+	vesa_pci_device.irq_pin = pin;
+	vesa_pci_device.irq_line = line;
+	pci__register(&vesa_pci_device, dev);
+	ioport__register(IOPORT_VESA, &vesa_io_ops, IOPORT_VESA_SIZE);
+
+	kvm__register_mmio(VESA_MEM_ADDR, VESA_MEM_SIZE, &vesa_mmio_callback);
+	pthread_create(&thread, NULL, vesa__dovnc, kvm);
+}
+
+/*
+ * This starts a VNC server to display the framebuffer.
+ * It's not altogether clear this belongs here rather than in kvm-run.c
+ */
+void *vesa__dovnc(void *v)
+{
+	/*
+	 * Make a fake argc and argv because the getscreen function
+	 * seems to want it.
+	 */
+	int ac = 1;
+	char av[1][1] = {{0} };
+	rfbScreenInfoPtr server;
+
+	server = rfbGetScreen(&ac, (char **)av, VESA_WIDTH, VESA_HEIGHT, 8, 3, 4);
+	server->frameBuffer = (char *)videomem;
+	server->alwaysShared = TRUE;
+	rfbInitServer(server);
+
+	while (rfbIsActive(server)) {
+		rfbMarkRectAsModified(server, 0, 0, VESA_WIDTH, VESA_HEIGHT);
+		rfbProcessEvents(server, server->deferUpdateTime * VESA_UPDATE_TIME);
+	}
+	return NULL;
+}

include/kvm/ioport.h

@@ -7,6 +7,8 @@
 
 /* some ports we reserve for own use */
 #define IOPORT_DBG			0xe0
+#define IOPORT_VESA			0xa200
+#define IOPORT_VESA_SIZE		256
 #define IOPORT_VIRTIO_P9		0xb200	/* Virtio 9P device */
 #define IOPORT_VIRTIO_P9_SIZE		256
 #define IOPORT_VIRTIO_BLK		0xc200	/* Virtio block device */

include/kvm/vesa.h

@@ -0,0 +1,27 @@
+#ifndef KVM__VESA_H
+#define KVM__VESA_H
+
+#include <linux/types.h>
+
+#define VESA_WIDTH	640
+#define VESA_HEIGHT	480
+
+#define VESA_MEM_ADDR	0xd0000000
+#define VESA_MEM_SIZE	(4*VESA_WIDTH*VESA_HEIGHT)
+#define VESA_BPP	32
+
+struct kvm;
+struct int10_args;
+
+void vesa_mmio_callback(u64, u8*, u32, u8);
+void vesa__init(struct kvm *self);
+void *vesa__dovnc(void *);
+void int10_handler(struct int10_args *args);
+
+#ifndef CONFIG_HAS_VNCSERVER
+void vesa__init(struct kvm *self) { }
+#endif
+
+extern u8 videomem[VESA_MEM_SIZE];
+
+#endif

include/kvm/virtio-pci-dev.h

@@ -13,8 +13,11 @@
 #define PCI_DEVICE_ID_VIRTIO_CONSOLE		0x1003
 #define PCI_DEVICE_ID_VIRTIO_RNG		0x1004
 #define PCI_DEVICE_ID_VIRTIO_P9			0x1009
+#define PCI_DEVICE_ID_VESA			0x2000
 
 #define PCI_VENDOR_ID_REDHAT_QUMRANET		0x1af4
 #define PCI_SUBSYSTEM_VENDOR_ID_REDHAT_QUMRANET	0x1af4
 
+#define PCI_SUBSYSTEM_ID_VESA			0x0004
+
 #endif /* VIRTIO_PCI_DEV_H_ */