xen: Add the Xen platform pci device

Introduce a new emulated PCI device, specific to fully virtualized Xen
guests.  The device is necessary for PV on HVM drivers to work.

Signed-off-by: Steven Smith <ssmith@xensource.com>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

6 files changed, 354 insertions, 0 deletions

diff --git a/Makefile.target b/Makefile.target
index b1a0f6d28b..760aa02d53 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -218,6 +218,8 @@ obj-$(CONFIG_NO_XEN) += xen-stub.o
 obj-i386-$(CONFIG_XEN_MAPCACHE) += xen-mapcache.o
 obj-$(CONFIG_NO_XEN_MAPCACHE) += xen-mapcache-stub.o
 
+obj-i386-$(CONFIG_XEN) += xen_platform.o
+
 # Inter-VM PCI shared memory
 CONFIG_IVSHMEM =
 ifeq ($(CONFIG_KVM), y)
diff --git a/hw/hw.h b/hw/hw.h
index 56447a735d..9dd7096fc2 100644
--- a/hw/hw.h
+++ b/hw/hw.h
@@ -780,6 +780,9 @@ extern const VMStateDescription vmstate_ptimer;
 #define VMSTATE_INT32_LE(_f, _s)                                   \
     VMSTATE_SINGLE(_f, _s, 0, vmstate_info_int32_le, int32_t)
 
+#define VMSTATE_UINT8_TEST(_f, _s, _t)                               \
+    VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_uint8, uint8_t)
+
 #define VMSTATE_UINT16_TEST(_f, _s, _t)                               \
     VMSTATE_SINGLE_TEST(_f, _s, _t, 0, vmstate_info_uint16, uint16_t)
 
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index ba198de8c1..8dbeb0c8ab 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -136,6 +136,10 @@ static void pc_init1(ram_addr_t ram_size,
 
     pc_vga_init(pci_enabled? pci_bus: NULL);
 
+    if (xen_enabled()) {
+        pci_create_simple(pci_bus, -1, "xen-platform");
+    }
+
     /* init basic PC hardware */
     pc_basic_device_init(isa_irq, &rtc_state, xen_enabled());
 
diff --git a/hw/pci_ids.h b/hw/pci_ids.h
index d9457ed3f4..d94578c87d 100644
--- a/hw/pci_ids.h
+++ b/hw/pci_ids.h
@@ -109,3 +109,5 @@
 #define PCI_DEVICE_ID_INTEL_82371AB      0x7111
 #define PCI_DEVICE_ID_INTEL_82371AB_2    0x7112
 #define PCI_DEVICE_ID_INTEL_82371AB_3    0x7113
+
+#define PCI_VENDOR_ID_XENSOURCE          0x5853
diff --git a/hw/xen_platform.c b/hw/xen_platform.c
new file mode 100644
index 0000000000..b167eee1ff
--- /dev/null
+++ b/hw/xen_platform.c
@@ -0,0 +1,340 @@
+/*
+ * XEN platform pci device, formerly known as the event channel device
+ *
+ * Copyright (c) 2003-2004 Intel Corp.
+ * Copyright (c) 2006 XenSource
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <assert.h>
+
+#include "hw.h"
+#include "pc.h"
+#include "pci.h"
+#include "irq.h"
+#include "xen_common.h"
+#include "net.h"
+#include "xen_backend.h"
+#include "rwhandler.h"
+#include "trace.h"
+
+#include <xenguest.h>
+
+//#define DEBUG_PLATFORM
+
+#ifdef DEBUG_PLATFORM
+#define DPRINTF(fmt, ...) do { \
+    fprintf(stderr, "xen_platform: " fmt, ## __VA_ARGS__); \
+} while (0)
+#else
+#define DPRINTF(fmt, ...) do { } while (0)
+#endif
+
+#define PFFLAG_ROM_LOCK 1 /* Sets whether ROM memory area is RW or RO */
+
+typedef struct PCIXenPlatformState {
+    PCIDevice  pci_dev;
+    uint8_t flags; /* used only for version_id == 2 */
+    int drivers_blacklisted;
+    uint16_t driver_product_version;
+
+    /* Log from guest drivers */
+    char log_buffer[4096];
+    int log_buffer_off;
+} PCIXenPlatformState;
+
+#define XEN_PLATFORM_IOPORT 0x10
+
+/* Send bytes to syslog */
+static void log_writeb(PCIXenPlatformState *s, char val)
+{
+    if (val == '\n' || s->log_buffer_off == sizeof(s->log_buffer) - 1) {
+        /* Flush buffer */
+        s->log_buffer[s->log_buffer_off] = 0;
+        trace_xen_platform_log(s->log_buffer);
+        s->log_buffer_off = 0;
+    } else {
+        s->log_buffer[s->log_buffer_off++] = val;
+    }
+}
+
+/* Xen Platform, Fixed IOPort */
+
+static void platform_fixed_ioport_writew(void *opaque, uint32_t addr, uint32_t val)
+{
+    PCIXenPlatformState *s = opaque;
+
+    switch (addr - XEN_PLATFORM_IOPORT) {
+    case 0:
+        /* TODO: */
+        /* Unplug devices.  Value is a bitmask of which devices to
+           unplug, with bit 0 the IDE devices, bit 1 the network
+           devices, and bit 2 the non-primary-master IDE devices. */
+        break;
+    case 2:
+        switch (val) {
+        case 1:
+            DPRINTF("Citrix Windows PV drivers loaded in guest\n");
+            break;
+        case 0:
+            DPRINTF("Guest claimed to be running PV product 0?\n");
+            break;
+        default:
+            DPRINTF("Unknown PV product %d loaded in guest\n", val);
+            break;
+        }
+        s->driver_product_version = val;
+        break;
+    }
+}
+
+static void platform_fixed_ioport_writel(void *opaque, uint32_t addr,
+                                         uint32_t val)
+{
+    switch (addr - XEN_PLATFORM_IOPORT) {
+    case 0:
+        /* PV driver version */
+        break;
+    }
+}
+
+static void platform_fixed_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
+{
+    PCIXenPlatformState *s = opaque;
+
+    switch (addr - XEN_PLATFORM_IOPORT) {
+    case 0: /* Platform flags */ {
+        hvmmem_type_t mem_type = (val & PFFLAG_ROM_LOCK) ?
+            HVMMEM_ram_ro : HVMMEM_ram_rw;
+        if (xc_hvm_set_mem_type(xen_xc, xen_domid, mem_type, 0xc0, 0x40)) {
+            DPRINTF("unable to change ro/rw state of ROM memory area!\n");
+        } else {
+            s->flags = val & PFFLAG_ROM_LOCK;
+            DPRINTF("changed ro/rw state of ROM memory area. now is %s state.\n",
+                    (mem_type == HVMMEM_ram_ro ? "ro":"rw"));
+        }
+        break;
+    }
+    case 2:
+        log_writeb(s, val);
+        break;
+    }
+}
+
+static uint32_t platform_fixed_ioport_readw(void *opaque, uint32_t addr)
+{
+    PCIXenPlatformState *s = opaque;
+
+    switch (addr - XEN_PLATFORM_IOPORT) {
+    case 0:
+        if (s->drivers_blacklisted) {
+            /* The drivers will recognise this magic number and refuse
+             * to do anything. */
+            return 0xd249;
+        } else {
+            /* Magic value so that you can identify the interface. */
+            return 0x49d2;
+        }
+    default:
+        return 0xffff;
+    }
+}
+
+static uint32_t platform_fixed_ioport_readb(void *opaque, uint32_t addr)
+{
+    PCIXenPlatformState *s = opaque;
+
+    switch (addr - XEN_PLATFORM_IOPORT) {
+    case 0:
+        /* Platform flags */
+        return s->flags;
+    case 2:
+        /* Version number */
+        return 1;
+    default:
+        return 0xff;
+    }
+}
+
+static void platform_fixed_ioport_reset(void *opaque)
+{
+    PCIXenPlatformState *s = opaque;
+
+    platform_fixed_ioport_writeb(s, XEN_PLATFORM_IOPORT, 0);
+}
+
+static void platform_fixed_ioport_init(PCIXenPlatformState* s)
+{
+    register_ioport_write(XEN_PLATFORM_IOPORT, 16, 4, platform_fixed_ioport_writel, s);
+    register_ioport_write(XEN_PLATFORM_IOPORT, 16, 2, platform_fixed_ioport_writew, s);
+    register_ioport_write(XEN_PLATFORM_IOPORT, 16, 1, platform_fixed_ioport_writeb, s);
+    register_ioport_read(XEN_PLATFORM_IOPORT, 16, 2, platform_fixed_ioport_readw, s);
+    register_ioport_read(XEN_PLATFORM_IOPORT, 16, 1, platform_fixed_ioport_readb, s);
+}
+
+/* Xen Platform PCI Device */
+
+static uint32_t xen_platform_ioport_readb(void *opaque, uint32_t addr)
+{
+    addr &= 0xff;
+
+    if (addr == 0) {
+        return platform_fixed_ioport_readb(opaque, XEN_PLATFORM_IOPORT);
+    } else {
+        return ~0u;
+    }
+}
+
+static void xen_platform_ioport_writeb(void *opaque, uint32_t addr, uint32_t val)
+{
+    PCIXenPlatformState *s = opaque;
+
+    addr &= 0xff;
+    val  &= 0xff;
+
+    switch (addr) {
+    case 0: /* Platform flags */
+        platform_fixed_ioport_writeb(opaque, XEN_PLATFORM_IOPORT, val);
+        break;
+    case 8:
+        log_writeb(s, val);
+        break;
+    default:
+        break;
+    }
+}
+
+static void platform_ioport_map(PCIDevice *pci_dev, int region_num, pcibus_t addr, pcibus_t size, int type)
+{
+    PCIXenPlatformState *d = DO_UPCAST(PCIXenPlatformState, pci_dev, pci_dev);
+
+    register_ioport_write(addr, size, 1, xen_platform_ioport_writeb, d);
+    register_ioport_read(addr, size, 1, xen_platform_ioport_readb, d);
+}
+
+static uint32_t platform_mmio_read(ReadWriteHandler *handler, pcibus_t addr, int len)
+{
+    DPRINTF("Warning: attempted read from physical address "
+            "0x" TARGET_FMT_plx " in xen platform mmio space\n", addr);
+
+    return 0;
+}
+
+static void platform_mmio_write(ReadWriteHandler *handler, pcibus_t addr,
+                                uint32_t val, int len)
+{
+    DPRINTF("Warning: attempted write of 0x%x to physical "
+            "address 0x" TARGET_FMT_plx " in xen platform mmio space\n",
+            val, addr);
+}
+
+static ReadWriteHandler platform_mmio_handler = {
+    .read = &platform_mmio_read,
+    .write = &platform_mmio_write,
+};
+
+static void platform_mmio_map(PCIDevice *d, int region_num,
+                              pcibus_t addr, pcibus_t size, int type)
+{
+    int mmio_io_addr;
+
+    mmio_io_addr = cpu_register_io_memory_simple(&platform_mmio_handler,
+                                                 DEVICE_NATIVE_ENDIAN);
+
+    cpu_register_physical_memory(addr, size, mmio_io_addr);
+}
+
+static int xen_platform_post_load(void *opaque, int version_id)
+{
+    PCIXenPlatformState *s = opaque;
+
+    platform_fixed_ioport_writeb(s, XEN_PLATFORM_IOPORT, s->flags);
+
+    return 0;
+}
+
+static const VMStateDescription vmstate_xen_platform = {
+    .name = "platform",
+    .version_id = 4,
+    .minimum_version_id = 4,
+    .minimum_version_id_old = 4,
+    .post_load = xen_platform_post_load,
+    .fields = (VMStateField []) {
+        VMSTATE_PCI_DEVICE(pci_dev, PCIXenPlatformState),
+        VMSTATE_UINT8(flags, PCIXenPlatformState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static int xen_platform_initfn(PCIDevice *dev)
+{
+    PCIXenPlatformState *d = DO_UPCAST(PCIXenPlatformState, pci_dev, dev);
+    uint8_t *pci_conf;
+
+    pci_conf = d->pci_dev.config;
+
+    pci_config_set_vendor_id(pci_conf, PCI_VENDOR_ID_XENSOURCE);
+    pci_config_set_device_id(pci_conf, 0x0001);
+    pci_set_word(pci_conf + PCI_SUBSYSTEM_VENDOR_ID, PCI_VENDOR_ID_XENSOURCE);
+    pci_set_word(pci_conf + PCI_SUBSYSTEM_ID, 0x0001);
+
+    pci_set_word(pci_conf + PCI_COMMAND, PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
+
+    pci_config_set_revision(pci_conf, 1);
+    pci_config_set_prog_interface(pci_conf, 0);
+
+    pci_config_set_class(pci_conf, PCI_CLASS_OTHERS << 8 | 0x80);
+
+    pci_conf[PCI_INTERRUPT_PIN] = 1;
+
+    pci_register_bar(&d->pci_dev, 0, 0x100,
+            PCI_BASE_ADDRESS_SPACE_IO, platform_ioport_map);
+
+    /* reserve 16MB mmio address for share memory*/
+    pci_register_bar(&d->pci_dev, 1, 0x1000000,
+            PCI_BASE_ADDRESS_MEM_PREFETCH, platform_mmio_map);
+
+    platform_fixed_ioport_init(d);
+
+    return 0;
+}
+
+static void platform_reset(DeviceState *dev)
+{
+    PCIXenPlatformState *s = DO_UPCAST(PCIXenPlatformState, pci_dev.qdev, dev);
+
+    platform_fixed_ioport_reset(s);
+}
+
+static PCIDeviceInfo xen_platform_info = {
+    .init = xen_platform_initfn,
+    .qdev.name = "xen-platform",
+    .qdev.desc = "XEN platform pci device",
+    .qdev.size = sizeof(PCIXenPlatformState),
+    .qdev.vmsd = &vmstate_xen_platform,
+    .qdev.reset = platform_reset,
+};
+
+static void xen_platform_register(void)
+{
+    pci_qdev_register(&xen_platform_info);
+}
+
+device_init(xen_platform_register);
diff --git a/trace-events b/trace-events
index 46a19d3725..bebf612fe9 100644
--- a/trace-events
+++ b/trace-events
@@ -407,3 +407,6 @@ disable xen_unmap_block(void* addr, unsigned long size) "%p, size %#lx"
 
 # exec.c
 disable qemu_put_ram_ptr(void* addr) "%p"
+
+# hw/xen_platform.c
+disable xen_platform_log(char *s) "xen platform: %s"