Implement the bus structure for PAPR virtual IO

This extends the "pseries" (PAPR) machine to include a virtual IO bus
supporting the PAPR defined hypercall based virtual IO mechanisms.

So far only one VIO device is provided, the vty / vterm, providing
a full console (polled only, for now).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 150 insertions, 0 deletions

diff --git a/hw/spapr_vty.c b/hw/spapr_vty.c
new file mode 100644
index 0000000000..b4da6a83fb
--- /dev/null
+++ b/hw/spapr_vty.c
@@ -0,0 +1,150 @@
+#include "qdev.h"
+#include "qemu-char.h"
+#include "hw/spapr.h"
+#include "hw/spapr_vio.h"
+
+#define VTERM_BUFSIZE   16
+
+typedef struct VIOsPAPRVTYDevice {
+    VIOsPAPRDevice sdev;
+    CharDriverState *chardev;
+    uint32_t in, out;
+    uint8_t buf[VTERM_BUFSIZE];
+} VIOsPAPRVTYDevice;
+
+static int vty_can_receive(void *opaque)
+{
+    VIOsPAPRVTYDevice *dev = (VIOsPAPRVTYDevice *)opaque;
+
+    return (dev->in - dev->out) < VTERM_BUFSIZE;
+}
+
+static void vty_receive(void *opaque, const uint8_t *buf, int size)
+{
+    VIOsPAPRVTYDevice *dev = (VIOsPAPRVTYDevice *)opaque;
+    int i;
+
+    for (i = 0; i < size; i++) {
+        assert((dev->in - dev->out) < VTERM_BUFSIZE);
+        dev->buf[dev->in++ % VTERM_BUFSIZE] = buf[i];
+    }
+}
+
+static int vty_getchars(VIOsPAPRDevice *sdev, uint8_t *buf, int max)
+{
+    VIOsPAPRVTYDevice *dev = (VIOsPAPRVTYDevice *)sdev;
+    int n = 0;
+
+    while ((n < max) && (dev->out != dev->in)) {
+        buf[n++] = dev->buf[dev->out++ % VTERM_BUFSIZE];
+    }
+
+    return n;
+}
+
+void vty_putchars(VIOsPAPRDevice *sdev, uint8_t *buf, int len)
+{
+    VIOsPAPRVTYDevice *dev = (VIOsPAPRVTYDevice *)sdev;
+
+    /* FIXME: should check the qemu_chr_write() return value */
+    qemu_chr_write(dev->chardev, buf, len);
+}
+
+static int spapr_vty_init(VIOsPAPRDevice *sdev)
+{
+    VIOsPAPRVTYDevice *dev = (VIOsPAPRVTYDevice *)sdev;
+
+    qemu_chr_add_handlers(dev->chardev, vty_can_receive,
+                          vty_receive, NULL, dev);
+
+    return 0;
+}
+
+static target_ulong h_put_term_char(CPUState *env, sPAPREnvironment *spapr,
+                                    target_ulong opcode, target_ulong *args)
+{
+    target_ulong reg = args[0];
+    target_ulong len = args[1];
+    target_ulong char0_7 = args[2];
+    target_ulong char8_15 = args[3];
+    VIOsPAPRDevice *sdev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
+    uint8_t buf[16];
+
+    if (!sdev) {
+        return H_PARAMETER;
+    }
+
+    if (len > 16) {
+        return H_PARAMETER;
+    }
+
+    *((uint64_t *)buf) = cpu_to_be64(char0_7);
+    *((uint64_t *)buf + 1) = cpu_to_be64(char8_15);
+
+    vty_putchars(sdev, buf, len);
+
+    return H_SUCCESS;
+}
+
+static target_ulong h_get_term_char(CPUState *env, sPAPREnvironment *spapr,
+                                    target_ulong opcode, target_ulong *args)
+{
+    target_ulong reg = args[0];
+    target_ulong *len = args + 0;
+    target_ulong *char0_7 = args + 1;
+    target_ulong *char8_15 = args + 2;
+    VIOsPAPRDevice *sdev = spapr_vio_find_by_reg(spapr->vio_bus, reg);
+    uint8_t buf[16];
+
+    if (!sdev) {
+        return H_PARAMETER;
+    }
+
+    *len = vty_getchars(sdev, buf, sizeof(buf));
+    if (*len < 16) {
+        memset(buf + *len, 0, 16 - *len);
+    }
+
+    *char0_7 = be64_to_cpu(*((uint64_t *)buf));
+    *char8_15 = be64_to_cpu(*((uint64_t *)buf + 1));
+
+    return H_SUCCESS;
+}
+
+void spapr_vty_create(VIOsPAPRBus *bus,
+                      uint32_t reg, CharDriverState *chardev)
+{
+    DeviceState *dev;
+
+    dev = qdev_create(&bus->bus, "spapr-vty");
+    qdev_prop_set_uint32(dev, "reg", reg);
+    qdev_prop_set_chr(dev, "chardev", chardev);
+    qdev_init_nofail(dev);
+}
+
+static void vty_hcalls(VIOsPAPRBus *bus)
+{
+    spapr_register_hypercall(H_PUT_TERM_CHAR, h_put_term_char);
+    spapr_register_hypercall(H_GET_TERM_CHAR, h_get_term_char);
+}
+
+static VIOsPAPRDeviceInfo spapr_vty = {
+    .init = spapr_vty_init,
+    .dt_name = "vty",
+    .dt_type = "serial",
+    .dt_compatible = "hvterm1",
+    .hcalls = vty_hcalls,
+    .qdev.name = "spapr-vty",
+    .qdev.size = sizeof(VIOsPAPRVTYDevice),
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_UINT32("reg", VIOsPAPRDevice, reg, 0),
+        DEFINE_PROP_CHR("chardev", VIOsPAPRVTYDevice, chardev),
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static void spapr_vty_register(void)
+{
+    spapr_vio_bus_register_withprop(&spapr_vty);
+}
+device_init(spapr_vty_register);