hw/core: Move the ARM sysbus-fdt to core

The ARM virt machine currently uses sysbus-fdt to create device tree
entries for dynamically created MMIO devices.

The RISC-V virt machine can also benefit from this, so move the code to
the core directory.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@amd.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-Id: <20220427234146.1130752-3-alistair.francis@opensource.wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

2 files changed, 572 insertions, 0 deletions

diff --git a/hw/core/meson.build b/hw/core/meson.build
index 0f884d6..7a4d02b 100644
--- a/hw/core/meson.build
+++ b/hw/core/meson.build
@@ -33,6 +33,7 @@ softmmu_ss.add(when: 'CONFIG_PTIMER', if_true: files('ptimer.c'))
 softmmu_ss.add(when: 'CONFIG_REGISTER', if_true: files('register.c'))
 softmmu_ss.add(when: 'CONFIG_SPLIT_IRQ', if_true: files('split-irq.c'))
 softmmu_ss.add(when: 'CONFIG_XILINX_AXI', if_true: files('stream.c'))
+softmmu_ss.add(when: 'CONFIG_PLATFORM_BUS', if_true: files('sysbus-fdt.c'))
 
 softmmu_ss.add(files(
   'cpu-sysemu.c',
diff --git a/hw/core/sysbus-fdt.c b/hw/core/sysbus-fdt.c
new file mode 100644
index 0000000..19d22cb
--- /dev/null
+++ b/hw/core/sysbus-fdt.c
@@ -0,0 +1,571 @@
+/*
+ * ARM Platform Bus device tree generation helpers
+ *
+ * Copyright (c) 2014 Linaro Limited
+ *
+ * Authors:
+ *  Alex Graf <agraf@suse.de>
+ *  Eric Auger <eric.auger@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2 or later, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include <libfdt.h>
+#ifdef CONFIG_LINUX
+#include <linux/vfio.h>
+#endif
+#include "hw/core/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"
+#include "hw/vfio/vfio-amd-xgbe.h"
+#include "hw/display/ramfb.h"
+#include "hw/arm/fdt.h"
+
+/*
+ * internal struct that contains the information to create dynamic
+ * sysbus device node
+ */
+typedef struct PlatformBusFDTData {
+    void *fdt; /* device tree handle */
+    int irq_start; /* index of the first IRQ usable by platform bus devices */
+    const char *pbus_node_name; /* name of the platform bus node */
+    PlatformBusDevice *pbus;
+} PlatformBusFDTData;
+
+/* struct that allows to match a device and create its FDT node */
+typedef struct BindingEntry {
+    const char *typename;
+    const char *compat;
+    int  (*add_fn)(SysBusDevice *sbdev, void *opaque);
+    bool (*match_fn)(SysBusDevice *sbdev, const struct BindingEntry *combo);
+} BindingEntry;
+
+/* helpers */
+
+typedef struct HostProperty {
+    const char *name;
+    bool optional;
+} HostProperty;
+
+#ifdef CONFIG_LINUX
+
+/**
+ * copy_properties_from_host
+ *
+ * copies properties listed in an array from host device tree to
+ * guest device tree. If a non optional property is not found, the
+ * function asserts. An optional property is ignored if not found
+ * in the host device tree.
+ * @props: array of HostProperty to copy
+ * @nb_props: number of properties in the array
+ * @host_dt: host device tree blob
+ * @guest_dt: guest device tree blob
+ * @node_path: host dt node path where the property is supposed to be
+              found
+ * @nodename: guest node name the properties should be added to
+ */
+static void copy_properties_from_host(HostProperty *props, int nb_props,
+                                      void *host_fdt, void *guest_fdt,
+                                      char *node_path, char *nodename)
+{
+    int i, prop_len;
+    const void *r;
+    Error *err = NULL;
+
+    for (i = 0; i < nb_props; i++) {
+        r = qemu_fdt_getprop(host_fdt, node_path,
+                             props[i].name,
+                             &prop_len,
+                             &err);
+        if (r) {
+            qemu_fdt_setprop(guest_fdt, nodename,
+                             props[i].name, r, prop_len);
+        } else {
+            if (props[i].optional && prop_len == -FDT_ERR_NOTFOUND) {
+                /* optional property does not exist */
+                error_free(err);
+            } else {
+                error_report_err(err);
+            }
+            if (!props[i].optional) {
+                /* mandatory property not found: bail out */
+                exit(1);
+            }
+            err = NULL;
+        }
+    }
+}
+
+/* clock properties whose values are copied/pasted from host */
+static HostProperty clock_copied_properties[] = {
+    {"compatible", false},
+    {"#clock-cells", false},
+    {"clock-frequency", true},
+    {"clock-output-names", true},
+};
+
+/**
+ * fdt_build_clock_node
+ *
+ * Build a guest clock node, used as a dependency from a passthrough'ed
+ * device. Most information are retrieved from the host clock node.
+ * Also check the host clock is a fixed one.
+ *
+ * @host_fdt: host device tree blob from which info are retrieved
+ * @guest_fdt: guest device tree blob where the clock node is added
+ * @host_phandle: phandle of the clock in host device tree
+ * @guest_phandle: phandle to assign to the guest node
+ */
+static void fdt_build_clock_node(void *host_fdt, void *guest_fdt,
+                                uint32_t host_phandle,
+                                uint32_t guest_phandle)
+{
+    char *node_path = NULL;
+    char *nodename;
+    const void *r;
+    int ret, node_offset, prop_len, path_len = 16;
+
+    node_offset = fdt_node_offset_by_phandle(host_fdt, host_phandle);
+    if (node_offset <= 0) {
+        error_report("not able to locate clock handle %d in host device tree",
+                     host_phandle);
+        exit(1);
+    }
+    node_path = g_malloc(path_len);
+    while ((ret = fdt_get_path(host_fdt, node_offset, node_path, path_len))
+            == -FDT_ERR_NOSPACE) {
+        path_len += 16;
+        node_path = g_realloc(node_path, path_len);
+    }
+    if (ret < 0) {
+        error_report("not able to retrieve node path for clock handle %d",
+                     host_phandle);
+        exit(1);
+    }
+
+    r = qemu_fdt_getprop(host_fdt, node_path, "compatible", &prop_len,
+                         &error_fatal);
+    if (strcmp(r, "fixed-clock")) {
+        error_report("clock handle %d is not a fixed clock", host_phandle);
+        exit(1);
+    }
+
+    nodename = strrchr(node_path, '/');
+    qemu_fdt_add_subnode(guest_fdt, nodename);
+
+    copy_properties_from_host(clock_copied_properties,
+                              ARRAY_SIZE(clock_copied_properties),
+                              host_fdt, guest_fdt,
+                              node_path, nodename);
+
+    qemu_fdt_setprop_cell(guest_fdt, nodename, "phandle", guest_phandle);
+
+    g_free(node_path);
+}
+
+/**
+ * sysfs_to_dt_name: convert the name found in sysfs into the node name
+ * for instance e0900000.xgmac is converted into xgmac@e0900000
+ * @sysfs_name: directory name in sysfs
+ *
+ * returns the device tree name upon success or NULL in case the sysfs name
+ * does not match the expected format
+ */
+static char *sysfs_to_dt_name(const char *sysfs_name)
+{
+    gchar **substrings =  g_strsplit(sysfs_name, ".", 2);
+    char *dt_name = NULL;
+
+    if (!substrings || !substrings[0] || !substrings[1]) {
+        goto out;
+    }
+    dt_name = g_strdup_printf("%s@%s", substrings[1], substrings[0]);
+out:
+    g_strfreev(substrings);
+    return dt_name;
+}
+
+/* Device Specific Code */
+
+/**
+ * add_calxeda_midway_xgmac_fdt_node
+ *
+ * Generates a simple node with following properties:
+ * compatible string, regs, interrupts, dma-coherent
+ */
+static int add_calxeda_midway_xgmac_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;
+    int compat_str_len, i;
+    char *nodename;
+    uint32_t *irq_attr, *reg_attr;
+    uint64_t mmio_base, irq_number;
+    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+
+    mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
+    nodename = g_strdup_printf("%s/%s@%" PRIx64, parent_node,
+                               vbasedev->name, mmio_base);
+    qemu_fdt_add_subnode(fdt, nodename);
+
+    compat_str_len = strlen(vdev->compat) + 1;
+    qemu_fdt_setprop(fdt, nodename, "compatible",
+                          vdev->compat, compat_str_len);
+
+    qemu_fdt_setprop(fdt, nodename, "dma-coherent", "", 0);
+
+    reg_attr = g_new(uint32_t, vbasedev->num_regions * 2);
+    for (i = 0; i < vbasedev->num_regions; i++) {
+        mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, i);
+        reg_attr[2 * i] = cpu_to_be32(mmio_base);
+        reg_attr[2 * i + 1] = cpu_to_be32(
+                                memory_region_size(vdev->regions[i]->mem));
+    }
+    qemu_fdt_setprop(fdt, nodename, "reg", reg_attr,
+                     vbasedev->num_regions * 2 * sizeof(uint32_t));
+
+    irq_attr = g_new(uint32_t, vbasedev->num_irqs * 3);
+    for (i = 0; i < vbasedev->num_irqs; i++) {
+        irq_number = platform_bus_get_irqn(pbus, sbdev , i)
+                         + data->irq_start;
+        irq_attr[3 * i] = cpu_to_be32(GIC_FDT_IRQ_TYPE_SPI);
+        irq_attr[3 * i + 1] = cpu_to_be32(irq_number);
+        irq_attr[3 * i + 2] = cpu_to_be32(GIC_FDT_IRQ_FLAGS_LEVEL_HI);
+    }
+    qemu_fdt_setprop(fdt, nodename, "interrupts",
+                     irq_attr, vbasedev->num_irqs * 3 * sizeof(uint32_t));
+    g_free(irq_attr);
+    g_free(reg_attr);
+    g_free(nodename);
+    return 0;
+}
+
+/* AMD xgbe properties whose values are copied/pasted from host */
+static HostProperty amd_xgbe_copied_properties[] = {
+    {"compatible", false},
+    {"dma-coherent", true},
+    {"amd,per-channel-interrupt", true},
+    {"phy-mode", false},
+    {"mac-address", true},
+    {"amd,speed-set", false},
+    {"amd,serdes-blwc", true},
+    {"amd,serdes-cdr-rate", true},
+    {"amd,serdes-pq-skew", true},
+    {"amd,serdes-tx-amp", true},
+    {"amd,serdes-dfe-tap-config", true},
+    {"amd,serdes-dfe-tap-enable", true},
+    {"clock-names", false},
+};
+
+/**
+ * add_amd_xgbe_fdt_node
+ *
+ * Generates the combined xgbe/phy node following kernel >=4.2
+ * binding documentation:
+ * Documentation/devicetree/bindings/net/amd-xgbe.txt:
+ * Also 2 clock nodes are created (dma and ptp)
+ *
+ * Asserts in case of error
+ */
+static int add_amd_xgbe_fdt_node(SysBusDevice *sbdev, void *opaque)
+{
+    PlatformBusFDTData *data = opaque;
+    PlatformBusDevice *pbus = data->pbus;
+    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
+    VFIODevice *vbasedev = &vdev->vbasedev;
+    VFIOINTp *intp;
+    const char *parent_node = data->pbus_node_name;
+    char **node_path, *nodename, *dt_name;
+    void *guest_fdt = data->fdt, *host_fdt;
+    const void *r;
+    int i, prop_len;
+    uint32_t *irq_attr, *reg_attr, *host_clock_phandles;
+    uint64_t mmio_base, irq_number;
+    uint32_t guest_clock_phandles[2];
+
+    host_fdt = load_device_tree_from_sysfs();
+
+    dt_name = sysfs_to_dt_name(vbasedev->name);
+    if (!dt_name) {
+        error_report("%s incorrect sysfs device name %s",
+                     __func__, vbasedev->name);
+        exit(1);
+    }
+    node_path = qemu_fdt_node_path(host_fdt, dt_name, vdev->compat,
+                                   &error_fatal);
+    if (!node_path || !node_path[0]) {
+        error_report("%s unable to retrieve node path for %s/%s",
+                     __func__, dt_name, vdev->compat);
+        exit(1);
+    }
+
+    if (node_path[1]) {
+        error_report("%s more than one node matching %s/%s!",
+                     __func__, dt_name, vdev->compat);
+        exit(1);
+    }
+
+    g_free(dt_name);
+
+    if (vbasedev->num_regions != 5) {
+        error_report("%s Does the host dt node combine XGBE/PHY?", __func__);
+        exit(1);
+    }
+
+    /* generate nodes for DMA_CLK and PTP_CLK */
+    r = qemu_fdt_getprop(host_fdt, node_path[0], "clocks",
+                         &prop_len, &error_fatal);
+    if (prop_len != 8) {
+        error_report("%s clocks property should contain 2 handles", __func__);
+        exit(1);
+    }
+    host_clock_phandles = (uint32_t *)r;
+    guest_clock_phandles[0] = qemu_fdt_alloc_phandle(guest_fdt);
+    guest_clock_phandles[1] = qemu_fdt_alloc_phandle(guest_fdt);
+
+    /**
+     * clock handles fetched from host dt are in be32 layout whereas
+     * rest of the code uses cpu layout. Also guest clock handles are
+     * in cpu layout.
+     */
+    fdt_build_clock_node(host_fdt, guest_fdt,
+                         be32_to_cpu(host_clock_phandles[0]),
+                         guest_clock_phandles[0]);
+
+    fdt_build_clock_node(host_fdt, guest_fdt,
+                         be32_to_cpu(host_clock_phandles[1]),
+                         guest_clock_phandles[1]);
+
+    /* combined XGBE/PHY node */
+    mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, 0);
+    nodename = g_strdup_printf("%s/%s@%" PRIx64, parent_node,
+                               vbasedev->name, mmio_base);
+    qemu_fdt_add_subnode(guest_fdt, nodename);
+
+    copy_properties_from_host(amd_xgbe_copied_properties,
+                       ARRAY_SIZE(amd_xgbe_copied_properties),
+                       host_fdt, guest_fdt,
+                       node_path[0], nodename);
+
+    qemu_fdt_setprop_cells(guest_fdt, nodename, "clocks",
+                           guest_clock_phandles[0],
+                           guest_clock_phandles[1]);
+
+    reg_attr = g_new(uint32_t, vbasedev->num_regions * 2);
+    for (i = 0; i < vbasedev->num_regions; i++) {
+        mmio_base = platform_bus_get_mmio_addr(pbus, sbdev, i);
+        reg_attr[2 * i] = cpu_to_be32(mmio_base);
+        reg_attr[2 * i + 1] = cpu_to_be32(
+                                memory_region_size(vdev->regions[i]->mem));
+    }
+    qemu_fdt_setprop(guest_fdt, nodename, "reg", reg_attr,
+                     vbasedev->num_regions * 2 * sizeof(uint32_t));
+
+    irq_attr = g_new(uint32_t, vbasedev->num_irqs * 3);
+    for (i = 0; i < vbasedev->num_irqs; i++) {
+        irq_number = platform_bus_get_irqn(pbus, sbdev , i)
+                         + data->irq_start;
+        irq_attr[3 * i] = cpu_to_be32(GIC_FDT_IRQ_TYPE_SPI);
+        irq_attr[3 * i + 1] = cpu_to_be32(irq_number);
+        /*
+          * General device interrupt and PCS auto-negotiation interrupts are
+          * level-sensitive while the 4 per-channel interrupts are edge
+          * sensitive
+          */
+        QLIST_FOREACH(intp, &vdev->intp_list, next) {
+            if (intp->pin == i) {
+                break;
+            }
+        }
+        if (intp->flags & VFIO_IRQ_INFO_AUTOMASKED) {
+            irq_attr[3 * i + 2] = cpu_to_be32(GIC_FDT_IRQ_FLAGS_LEVEL_HI);
+        } else {
+            irq_attr[3 * i + 2] = cpu_to_be32(GIC_FDT_IRQ_FLAGS_EDGE_LO_HI);
+        }
+    }
+    qemu_fdt_setprop(guest_fdt, nodename, "interrupts",
+                     irq_attr, vbasedev->num_irqs * 3 * sizeof(uint32_t));
+
+    g_free(host_fdt);
+    g_strfreev(node_path);
+    g_free(irq_attr);
+    g_free(reg_attr);
+    g_free(nodename);
+    return 0;
+}
+
+/* DT compatible matching */
+static bool vfio_platform_match(SysBusDevice *sbdev,
+                                const BindingEntry *entry)
+{
+    VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(sbdev);
+    const char *compat;
+    unsigned int n;
+
+    for (n = vdev->num_compat, compat = vdev->compat; n > 0;
+         n--, compat += strlen(compat) + 1) {
+        if (!strcmp(entry->compat, compat)) {
+            return true;
+        }
+    }
+
+    return false;
+}
+
+#define VFIO_PLATFORM_BINDING(compat, add_fn) \
+    {TYPE_VFIO_PLATFORM, (compat), (add_fn), vfio_platform_match}
+
+#endif /* CONFIG_LINUX */
+
+#ifdef CONFIG_TPM
+/*
+ * 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
+
+static int no_fdt_node(SysBusDevice *sbdev, void *opaque)
+{
+    return 0;
+}
+
+/* Device type based matching */
+static bool type_match(SysBusDevice *sbdev, const BindingEntry *entry)
+{
+    return !strcmp(object_get_typename(OBJECT(sbdev)), entry->typename);
+}
+
+#define TYPE_BINDING(type, add_fn) {(type), NULL, (add_fn), NULL}
+
+/* list of supported dynamic sysbus bindings */
+static const BindingEntry bindings[] = {
+#ifdef CONFIG_LINUX
+    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),
+#endif
+#ifdef CONFIG_TPM
+    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 */
+};
+
+/* Generic Code */
+
+/**
+ * add_fdt_node - add the device tree node of a dynamic sysbus device
+ *
+ * @sbdev: handle to the sysbus device
+ * @opaque: handle to the PlatformBusFDTData
+ *
+ * Checks the sysbus type belongs to the list of device types that
+ * are dynamically instantiable and if so call the node creation
+ * function.
+ */
+static void add_fdt_node(SysBusDevice *sbdev, void *opaque)
+{
+    int i, ret;
+
+    for (i = 0; i < ARRAY_SIZE(bindings); i++) {
+        const BindingEntry *iter = &bindings[i];
+
+        if (type_match(sbdev, iter)) {
+            if (!iter->match_fn || iter->match_fn(sbdev, iter)) {
+                ret = iter->add_fn(sbdev, opaque);
+                assert(!ret);
+                return;
+            }
+        }
+    }
+    error_report("Device %s can not be dynamically instantiated",
+                     qdev_fw_name(DEVICE(sbdev)));
+    exit(1);
+}
+
+void platform_bus_add_all_fdt_nodes(void *fdt, const char *intc, hwaddr addr,
+                                    hwaddr bus_size, int irq_start)
+{
+    const char platcomp[] = "qemu,platform\0simple-bus";
+    PlatformBusDevice *pbus;
+    DeviceState *dev;
+    gchar *node;
+
+    assert(fdt);
+
+    node = g_strdup_printf("/platform@%"PRIx64, addr);
+
+    /* Create a /platform node that we can put all devices into */
+    qemu_fdt_add_subnode(fdt, node);
+    qemu_fdt_setprop(fdt, node, "compatible", platcomp, sizeof(platcomp));
+
+    /* Our platform bus region is less than 32bits, so 1 cell is enough for
+     * address and size
+     */
+    qemu_fdt_setprop_cells(fdt, node, "#size-cells", 1);
+    qemu_fdt_setprop_cells(fdt, node, "#address-cells", 1);
+    qemu_fdt_setprop_cells(fdt, node, "ranges", 0, addr >> 32, addr, bus_size);
+
+    qemu_fdt_setprop_phandle(fdt, node, "interrupt-parent", intc);
+
+    dev = qdev_find_recursive(sysbus_get_default(), TYPE_PLATFORM_BUS_DEVICE);
+    pbus = PLATFORM_BUS_DEVICE(dev);
+
+    PlatformBusFDTData data = {
+        .fdt = fdt,
+        .irq_start = irq_start,
+        .pbus_node_name = node,
+        .pbus = pbus,
+    };
+
+    /* Loop through all dynamic sysbus devices and create their node */
+    foreach_dynamic_sysbus_device(add_fdt_node, &data);
+
+    g_free(node);
+}