hw/arm/virt: vTPM support

Let the TPM TIS SYSBUS device be dynamically instantiable
in ARM virt.  A device tree node is dynamically created
(TPM via MMIO).

The TPM Physical Presence interface (PPI) is not supported.

To run with the swtmp TPM emulator, the qemu command line must
be augmented with:

        -chardev socket,id=chrtpm,path=swtpm-sock \
        -tpmdev emulator,id=tpm0,chardev=chrtpm \
        -device tpm-tis-device,tpmdev=tpm0 \

swtpm/libtpms command line example:

swtpm socket --tpm2 -t -d --tpmstate dir=/tmp/tpm \
--ctrl type=unixio,path=swtpm-sock

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Message-id: 20200305165149.618-7-eric.auger@redhat.com
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c
index 022fc97ecd..6b6906f4cf 100644
--- a/hw/arm/sysbus-fdt.c
+++ b/hw/arm/sysbus-fdt.c
@@ -30,6 +30,7 @@
 #include "hw/arm/sysbus-fdt.h"
 #include "qemu/error-report.h"
 #include "sysemu/device_tree.h"
+#include "sysemu/tpm.h"
 #include "hw/platform-bus.h"
 #include "hw/vfio/vfio-platform.h"
 #include "hw/vfio/vfio-calxeda-xgmac.h"
@@ -436,6 +437,37 @@ static bool vfio_platform_match(SysBusDevice *sbdev,
 
 #endif /* CONFIG_LINUX */
 
+/*
+ * add_tpm_tis_fdt_node: Create a DT node for TPM TIS
+ *
+ * See kernel documentation:
+ * Documentation/devicetree/bindings/security/tpm/tpm_tis_mmio.txt
+ * Optional interrupt for command completion is not exposed
+ */
+static int add_tpm_tis_fdt_node(SysBusDevice *sbdev, void *opaque)
+{
+    PlatformBusFDTData *data = opaque;
+    PlatformBusDevice *pbus = data->pbus;
+    void *fdt = data->fdt;
+    const char *parent_node = data->pbus_node_name;
+    char *nodename;
+    uint32_t reg_attr[2];
+    uint64_t mmio_base;
+
+    mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
+    nodename = g_strdup_printf("%s/tpm_tis@%" PRIx64, parent_node, mmio_base);
+    qemu_fdt_add_subnode(fdt, nodename);
+
+    qemu_fdt_setprop_string(fdt, nodename, "compatible", "tcg,tpm-tis-mmio");
+
+    reg_attr[0] = cpu_to_be32(mmio_base);
+    reg_attr[1] = cpu_to_be32(0x5000);
+    qemu_fdt_setprop(fdt, nodename, "reg", reg_attr, 2 * sizeof(uint32_t));
+
+    g_free(nodename);
+    return 0;
+}
+
 static int no_fdt_node(SysBusDevice *sbdev, void *opaque)
 {
     return 0;
@@ -456,6 +488,7 @@ static const BindingEntry bindings[] = {
     TYPE_BINDING(TYPE_VFIO_AMD_XGBE, add_amd_xgbe_fdt_node),
     VFIO_PLATFORM_BINDING("amd,xgbe-seattle-v1a", add_amd_xgbe_fdt_node),
 #endif
+    TYPE_BINDING(TYPE_TPM_TIS_SYSBUS, add_tpm_tis_fdt_node),
     TYPE_BINDING(TYPE_RAMFB_DEVICE, no_fdt_node),
     TYPE_BINDING("", NULL), /* last element */
 };