diff options
Diffstat (limited to 'hw/arm/sysbus-fdt.c')
-rw-r--r-- | hw/arm/sysbus-fdt.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c index 68a3de5cf8..8575cfe3b6 100644 --- a/hw/arm/sysbus-fdt.c +++ b/hw/arm/sysbus-fdt.c @@ -22,6 +22,7 @@ */ #include "qemu/osdep.h" +#include <libfdt.h> #include "hw/arm/sysbus-fdt.h" #include "qemu/error-report.h" #include "sysemu/device_tree.h" @@ -57,6 +58,125 @@ typedef struct NodeCreationPair { int (*add_fdt_node_fn)(SysBusDevice *sbdev, void *opaque); } NodeCreationPair; +/* helpers */ + +typedef struct HostProperty { + const char *name; + bool optional; +} HostProperty; + +/** + * 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, + props[i].optional ? &err : &error_fatal); + if (r) { + qemu_fdt_setprop(guest_fdt, nodename, + props[i].name, r, prop_len); + } else { + if (prop_len != -FDT_ERR_NOTFOUND) { + /* optional property not returned although property exists */ + error_report_err(err); + } else { + error_free(err); + } + } + } +} + +/* 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 + */ +void fdt_build_clock_node(void *host_fdt, void *guest_fdt, + uint32_t host_phandle, + uint32_t guest_phandle); +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_setg(&error_fatal, + "not able to locate clock handle %d in host device tree", + host_phandle); + } + 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_setg(&error_fatal, + "not able to retrieve node path for clock handle %d", + host_phandle); + } + + r = qemu_fdt_getprop(host_fdt, node_path, "compatible", &prop_len, + &error_fatal); + if (strcmp(r, "fixed-clock")) { + error_setg(&error_fatal, + "clock handle %d is not a fixed clock", host_phandle); + } + + 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); +} + /* Device Specific Code */ /** |