[PATCH v3 06/10] hw/arm/virt: vTPM support

[Eric Auger <eric.auger@redhat.com>]

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>

---

v2 -> v3:
- use qemu_fdt_setprop_string()
---
 hw/arm/Kconfig      |  1 +
 hw/arm/sysbus-fdt.c | 33 +++++++++++++++++++++++++++++++++
 hw/arm/virt.c       |  7 +++++++
 3 files changed, 41 insertions(+)

diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index 3d86691ae0..b6f03f7f53 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -5,6 +5,7 @@ config ARM_VIRT
     imply VFIO_AMD_XGBE
     imply VFIO_PLATFORM
     imply VFIO_XGMAC
+    imply TPM_TIS_SYSBUS
     select A15MPCORE
     select ACPI
     select ARM_SMMUV3
diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c
index 022fc97ecd..f603787b65 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"
@@ -434,6 +435,37 @@ static bool vfio_platform_match(SysBusDevice *sbdev,
 #define VFIO_PLATFORM_BINDING(compat, add_fn) \
     {TYPE_VFIO_PLATFORM, (compat), (add_fn), vfio_platform_match}
 
+/*
+ * 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;
+}
+
 #endif /* CONFIG_LINUX */
 
 static int no_fdt_node(SysBusDevice *sbdev, void *opaque)
@@ -455,6 +487,7 @@ static const BindingEntry bindings[] = {
     TYPE_BINDING(TYPE_VFIO_CALXEDA_XGMAC, add_calxeda_midway_xgmac_fdt_node),
     TYPE_BINDING(TYPE_VFIO_AMD_XGBE, add_amd_xgbe_fdt_node),
     VFIO_PLATFORM_BINDING("amd,xgbe-seattle-v1a", add_amd_xgbe_fdt_node),
+    TYPE_BINDING(TYPE_TPM_TIS_SYSBUS, add_tpm_tis_fdt_node),
 #endif
     TYPE_BINDING(TYPE_RAMFB_DEVICE, no_fdt_node),
     TYPE_BINDING("", NULL), /* last element */
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index f788fe27d6..4b967e39d1 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -47,6 +47,7 @@
 #include "sysemu/numa.h"
 #include "sysemu/runstate.h"
 #include "sysemu/sysemu.h"
+#include "sysemu/tpm.h"
 #include "sysemu/kvm.h"
 #include "hw/loader.h"
 #include "exec/address-spaces.h"
@@ -2041,6 +2042,7 @@ static void virt_machine_class_init(ObjectClass *oc, void *data)
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_AMD_XGBE);
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_RAMFB_DEVICE);
     machine_class_allow_dynamic_sysbus_dev(mc, TYPE_VFIO_PLATFORM);
+    machine_class_allow_dynamic_sysbus_dev(mc, TYPE_TPM_TIS_SYSBUS);
     mc->block_default_type = IF_VIRTIO;
     mc->no_cdrom = 1;
     mc->pci_allow_0_address = true;
@@ -2153,6 +2155,11 @@ type_init(machvirt_machine_init);
 
 static void virt_machine_5_0_options(MachineClass *mc)
 {
+    static GlobalProperty compat[] = {
+        { TYPE_TPM_TIS_SYSBUS, "ppi", "false" },
+    };
+
+    compat_props_add(mc->compat_props, compat, G_N_ELEMENTS(compat));
 }
 DEFINE_VIRT_MACHINE_AS_LATEST(5, 0)
 
-- 
2.20.1