| Message ID | 1452093205-30167-6-git-send-email-eric.auger@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
Hi David, On 01/11/2016 03:41 AM, David Gibson wrote: > On Wed, Jan 06, 2016 at 03:13:23PM +0000, Eric Auger wrote: >> Some passthrough'ed devices depend on clock nodes. Those need to be >> generated in the guest device tree. This patch introduces some helpers >> to build a clock node from information retrieved in the host device tree. >> >> - inherit_properties copies properties from a host device tree node to >> a guest device tree node > > I dislike the name, since the first thing I think when I see "inherit" > is that it's about a node inheriting a property from an ancestor node, > not the guest inheriting properties from the host. Maybe > "passthrough_properties()"? No Problem, I will rename the function Best Regards Eric > >> - fdt_build_clock_node builds a guest clock node and checks the host >> fellow clock is a fixed one. >> >> fdt_build_clock_node will become static as soon as it gets used. A >> dummy pre-declaration is needed for compilation of this patch. >> >> Signed-off-by: Eric Auger <eric.auger@linaro.org> >> >> --- >> >> v1 -> v2: >> - inherit properties now outputs an error message in case >> qemu_fdt_getprop fails for an existing optional property >> - no hardcoded fixed buffer length >> - fdt_build_clock_node becomes void and auto-asserts on error >> - use boolean values when defining the clock properties >> >> RFC -> v1: >> - use the new proto of qemu_fdt_getprop >> - remove newline in error_report >> - fix some style issues >> --- >> hw/arm/sysbus-fdt.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 120 insertions(+) >> >> diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c >> index 9d28797..a1cf57b 100644 >> --- a/hw/arm/sysbus-fdt.c >> +++ b/hw/arm/sysbus-fdt.c >> @@ -21,6 +21,7 @@ >> * >> */ >> >> +#include <libfdt.h> >> #include "hw/arm/sysbus-fdt.h" >> #include "qemu/error-report.h" >> #include "sysemu/device_tree.h" >> @@ -56,6 +57,125 @@ typedef struct NodeCreationPair { >> int (*add_fdt_node_fn)(SysBusDevice *sbdev, void *opaque); >> } NodeCreationPair; >> >> +/* helpers */ >> + >> +typedef struct HostProperty { >> + const char *name; >> + bool optional; >> +} HostProperty; >> + >> +/** >> + * inherit_properties >> + * >> + * copies properties listed in an array from host device tree to >> + * guest device tree. If a non optional property is not found, the >> + * function self-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 inherit_properties(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_inherited_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); >> + >> + inherit_properties(clock_inherited_properties, >> + ARRAY_SIZE(clock_inherited_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 */ >> >> /** >
diff --git a/hw/arm/sysbus-fdt.c b/hw/arm/sysbus-fdt.c index 9d28797..a1cf57b 100644 --- a/hw/arm/sysbus-fdt.c +++ b/hw/arm/sysbus-fdt.c @@ -21,6 +21,7 @@ * */ +#include <libfdt.h> #include "hw/arm/sysbus-fdt.h" #include "qemu/error-report.h" #include "sysemu/device_tree.h" @@ -56,6 +57,125 @@ typedef struct NodeCreationPair { int (*add_fdt_node_fn)(SysBusDevice *sbdev, void *opaque); } NodeCreationPair; +/* helpers */ + +typedef struct HostProperty { + const char *name; + bool optional; +} HostProperty; + +/** + * inherit_properties + * + * copies properties listed in an array from host device tree to + * guest device tree. If a non optional property is not found, the + * function self-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 inherit_properties(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_inherited_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); + + inherit_properties(clock_inherited_properties, + ARRAY_SIZE(clock_inherited_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 */ /**
Some passthrough'ed devices depend on clock nodes. Those need to be generated in the guest device tree. This patch introduces some helpers to build a clock node from information retrieved in the host device tree. - inherit_properties copies properties from a host device tree node to a guest device tree node - fdt_build_clock_node builds a guest clock node and checks the host fellow clock is a fixed one. fdt_build_clock_node will become static as soon as it gets used. A dummy pre-declaration is needed for compilation of this patch. Signed-off-by: Eric Auger <eric.auger@linaro.org> --- v1 -> v2: - inherit properties now outputs an error message in case qemu_fdt_getprop fails for an existing optional property - no hardcoded fixed buffer length - fdt_build_clock_node becomes void and auto-asserts on error - use boolean values when defining the clock properties RFC -> v1: - use the new proto of qemu_fdt_getprop - remove newline in error_report - fix some style issues --- hw/arm/sysbus-fdt.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) -- 1.9.1