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[Xen-changelog] [xen master] xen/dts: Add new helpers to use the device tree

Date: Sat, 21 Sep 2013 04:22:45 +0000

Delivery-date: Sat, 21 Sep 2013 04:22:54 +0000

List-id: "Change log for Mercurial \(receive only\)" <xen-changelog.lists.xen.org>

commit c88d32f463f75664285fd98856a7cdc6e01409bc Author: Julien Grall <julien.grall@xxxxxxxxxx> AuthorDate: Fri Sep 13 13:49:11 2013 +0100 Commit: Ian Campbell <ian.campbell@xxxxxxxxxx> CommitDate: Tue Sep 17 15:27:48 2013 +0100 xen/dts: Add new helpers to use the device tree List of new helpers taken from linux (commit 74b9272): - dt_property_read_string - dt_match_node - dt_find_maching_node - dt_device_is_available - dt_prop_cmp Other new helpers: - dt_set_cell - dt_for_each_child - dt_set_range - dt_cells_to_size - dt_next_cell - dt_get_range - dt_node_name_is_equal - dt_node_path_is_equal - dt_property_name_is_equal Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx> Acked-by: Ian Campbell <ian.campbell@xxxxxxxxxx> --- xen/common/device_tree.c | 109 +++++++++++++++++++++++++++-- xen/include/xen/device_tree.h | 151 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 252 insertions(+), 8 deletions(-) diff --git a/xen/common/device_tree.c b/xen/common/device_tree.c index 61134fe..7e451b1 100644 --- a/xen/common/device_tree.c +++ b/xen/common/device_tree.c @@ -182,23 +182,38 @@ void __init device_tree_get_reg(const u32 **cell, u32 address_cells, get_val(cell, size_cells, size); } -static void __init set_val(u32 **cell, u32 cells, u64 val) +void dt_get_range(const __be32 **cell, const struct dt_device_node *np, + u64 *address, u64 *size) { - u32 c = cells; + *address = dt_next_cell(dt_n_addr_cells(np), cell); + *size = dt_next_cell(dt_n_size_cells(np), cell); +} + +void dt_set_cell(__be32 **cellp, int size, u64 val) +{ + int cells = size; - while ( c-- ) + while ( size-- ) { - (*cell)[c] = cpu_to_fdt32(val); + (*cellp)[size] = cpu_to_fdt32(val); val >>= 32; } - (*cell) += cells; + + (*cellp) += cells; } void __init device_tree_set_reg(u32 **cell, u32 address_cells, u32 size_cells, u64 start, u64 size) { - set_val(cell, address_cells, start); - set_val(cell, size_cells, size); + dt_set_cell(cell, address_cells, start); + dt_set_cell(cell, size_cells, size); +} + +void dt_set_range(__be32 **cellp, const struct dt_device_node *np, + u64 address, u64 size) +{ + dt_set_cell(cellp, dt_n_addr_cells(np), address); + dt_set_cell(cellp, dt_n_size_cells(np), size); } u32 __init device_tree_get_u32(const void *fdt, int node, const char *prop_name, @@ -583,6 +598,23 @@ bool_t dt_property_read_u32(const struct dt_device_node *np, return 1; } +int dt_property_read_string(const struct dt_device_node *np, + const char *propname, const char **out_string) +{ + const struct dt_property *pp = dt_find_property(np, propname, NULL); + + if ( !pp ) + return -EINVAL; + if ( !pp->value ) + return -ENODATA; + if ( strnlen(pp->value, pp->length) >= pp->length ) + return -EILSEQ; + + *out_string = pp->value; + + return 0; +} + bool_t dt_device_is_compatible(const struct dt_device_node *device, const char *compat) { @@ -655,6 +687,34 @@ struct dt_device_node *dt_find_node_by_alias(const char *alias) return NULL; } +bool_t dt_match_node(const struct dt_device_match *matches, + const struct dt_device_node *node) +{ + if ( !matches ) + return 0; + + while ( matches->path || matches->type || matches->compatible ) + { + bool_t match = 1; + + if ( matches->path ) + match &= dt_node_path_is_equal(node, matches->path); + + if ( matches->type ) + match &= dt_device_type_is_equal(node, matches->type); + + if ( matches->compatible ) + match &= dt_device_is_compatible(node, matches->compatible); + + if ( match ) + return match; + + matches++; + } + + return 0; +} + const struct dt_device_node *dt_get_parent(const struct dt_device_node *node) { if ( !node ) @@ -684,6 +744,23 @@ dt_find_compatible_node(struct dt_device_node *from, return np; } +struct dt_device_node * +dt_find_matching_node(struct dt_device_node *from, + const struct dt_device_match *matches) +{ + struct dt_device_node *np; + struct dt_device_node *dt; + + dt = from ? from->allnext : dt_host; + dt_for_each_device_node(dt, np) + { + if ( dt_match_node(matches, np) ) + return np; + } + + return NULL; +} + int dt_n_addr_cells(const struct dt_device_node *np) { const __be32 *ip; @@ -1372,6 +1449,24 @@ int dt_device_get_irq(const struct dt_device_node *device, int index, return dt_irq_translate(&raw, out_irq); } +bool_t dt_device_is_available(const struct dt_device_node *device) +{ + const char *status; + u32 statlen; + + status = dt_get_property(device, "status", &statlen); + if ( status == NULL ) + return 1; + + if ( statlen > 0 ) + { + if ( !strcmp(status, "okay") || !strcmp(status, "ok") ) + return 1; + } + + return 0; +} + /** * unflatten_dt_node - Alloc and populate a device_node from the flat tree * @fdt: The parent device tree blob diff --git a/xen/include/xen/device_tree.h b/xen/include/xen/device_tree.h index ca8371e..91caf1f 100644 --- a/xen/include/xen/device_tree.h +++ b/xen/include/xen/device_tree.h @@ -54,6 +54,19 @@ struct dt_early_info { struct dt_module_info modules; }; +/* + * Struct used for matching a device + */ +struct dt_device_match { + const char *path; + const char *type; + const char *compatible; +}; + +#define DT_MATCH_PATH(p) { .path = p } +#define DT_MATCH_TYPE(typ) { .type = typ } +#define DT_MATCH_COMPATIBLE(compat) { .compatible = compat } + typedef u32 dt_phandle; /** @@ -229,6 +242,7 @@ extern const struct dt_device_node *dt_interrupt_controller; */ struct dt_device_node * __init dt_find_interrupt_controller(const char *compat); +#define dt_prop_cmp(s1, s2) strcmp((s1), (s2)) #define dt_node_cmp(s1, s2) strcmp((s1), (s2)) #define dt_compat_cmp(s1, s2, l) strnicmp((s1), (s2), l) @@ -242,6 +256,9 @@ struct dt_device_node * __init dt_find_interrupt_controller(const char *compat); #define dt_for_each_device_node(dt, dn) \ for ( dn = dt; dn != NULL; dn = dn->allnext ) +#define dt_for_each_child_node(dt, dn) \ + for ( dn = dt->child; dn != NULL; dn = dn->sibling ) + /* Helper to read a big number; size is in cells (not bytes) */ static inline u64 dt_read_number(const __be32 *cell, int size) { @@ -252,6 +269,20 @@ static inline u64 dt_read_number(const __be32 *cell, int size) return r; } +/* Helper to convert a number of cells in bytes */ +static inline int dt_cells_to_size(int size) +{ + return (size * sizeof (u32)); +} + +static inline u64 dt_next_cell(int s, const __be32 **cellp) +{ + const __be32 *p = *cellp; + + *cellp = p + s; + return dt_read_number(p, s); +} + static inline const char *dt_node_full_name(const struct dt_device_node *np) { return (np && np->full_name) ? np->full_name : "<no-node>"; @@ -262,6 +293,18 @@ static inline const char *dt_node_name(const struct dt_device_node *np) return (np && np->name) ? np->name : "<no-node>"; } +static inline bool_t dt_node_name_is_equal(const struct dt_device_node *np, + const char *name) +{ + return !dt_node_cmp(np->name, name); +} + +static inline bool_t dt_node_path_is_equal(const struct dt_device_node *np, + const char *path) +{ + return !dt_node_cmp(np->full_name, path); +} + static inline bool_t dt_device_type_is_equal(const struct dt_device_node *device, const char *type) @@ -281,6 +324,12 @@ static inline domid_t dt_device_used_by(const struct dt_device_node *device) return device->used_by; } +static inline bool_t dt_property_name_is_equal(const struct dt_property *pp, + const char *name) +{ + return !dt_prop_cmp(pp->name, name); +} + /** * dt_find_compatible_node - Find a node based on type and one of the * tokens in its "compatible" property @@ -315,6 +364,23 @@ const void *dt_get_property(const struct dt_device_node *np, */ bool_t dt_property_read_u32(const struct dt_device_node *np, const char *name, u32 *out_value); +/** + * dt_property_read_string - Find and read a string from a property + * @np: Device node from which the property value is to be read + * @propname: Name of the property to be searched + * @out_string: Pointer to null terminated return string, modified only + * if return value if 0. + * + * Search for a property in a device tree node and retrieve a null + * terminated string value (pointer to data, not a copy). Returns 0 on + * success, -EINVAL if the property does not exist, -ENODATA if property + * doest not have value, and -EILSEQ if the string is not + * null-terminated with the length of the property data. + * + * The out_string pointer is modified only if a valid string can be decoded. + */ +int dt_property_read_string(const struct dt_device_node *np, + const char *propname, const char **out_string); /** * Checks if the given "compat" string matches one of the strings in @@ -450,4 +516,87 @@ int dt_n_size_cells(const struct dt_device_node *np); */ int dt_n_addr_cells(const struct dt_device_node *np); -#endif +/** + * dt_device_is_available - Check if a device is available for use + * + * @device: Node to check for availability + * + * Returns true if the status property is absent or set to "okay" or "ok", + * false otherwise. + */ +bool_t dt_device_is_available(const struct dt_device_node *device); + +/** + * dt_match_node - Tell if a device_node has a matching of dt_device_match + * @matches: array of dt_device_match structures to search in + * @node: the dt_device_node structure to match against + * + * Returns true if the device node match one of dt_device_match. + */ +bool_t dt_match_node(const struct dt_device_match *matches, + const struct dt_device_node *node); + +/** + * dt_find_matching_node - Find a node based on an dt_device_match match table + * @from: The node to start searching from or NULL, the node you pass + * will not be searched, only the next one will; typically, you pass + * what the returned call returned + * @matches: array of dt_device_match structures to search in + * + * Returns a node pointer. + */ +struct dt_device_node * +dt_find_matching_node(struct dt_device_node *from, + const struct dt_device_match *matches); + +/** + * dt_set_cell - Write a value into a series of cells + * + * @cellp: Pointer to cells + * @size: number of cells to write the value + * @value: number to write + * + * Write a value into a series of cells and update cellp to point to the + * cell just after. + */ +void dt_set_cell(__be32 **cellp, int size, u64 val); + +/** + * dt_set_range - Write range into a series of cells + * + * @cellp: Pointer to cells + * @np: Node which contains the encoding for the address and the size + * @address: Start of range + * @size: Size of the range + * + * Write a range into a series of cells and update cellp to point to the + * cell just after. + */ +void dt_set_range(__be32 **cellp, const struct dt_device_node *np, + u64 address, u64 size); + +/** + * dt_get_range - Read a range (address/size) from a series of cells + * + * @cellp: Pointer to cells + * @np Node which contains the encoding for the addresss and the size + * @address: Address filled by this function + * @size: Size filled by this function + * + * WARNING: This function should not be used to decode an address + * This function reads a range (address/size) from a series of cells and + * update cellp to point to the cell just after. + */ +void dt_get_range(const __be32 **cellp, const struct dt_device_node *np, + u64 *address, u64 *size); + +#endif /* __XEN_DEVICE_TREE_H */ + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * indent-tabs-mode: nil + * End: + */ -- generated by git-patchbot for /home/xen/git/xen.git#master _______________________________________________ Xen-changelog mailing list Xen-changelog@xxxxxxxxxxxxx http://lists.xensource.com/xen-changelog

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