Re: [RFC 09/24] xen/dts: Add new helpers to use the device tree

[Julien Grall <julien.grall@linaro.org>]

On 08/22/2013 02:21 PM, Ian Campbell wrote:
> <insert which new helpers here>

I will update the commit message on the next patch series.

> I think this is also reimplementing the internals of some existing
> dt_match_foo? And changing set_val into dt_set_cell. IOW there seems to
> be more changes than the single line changelog would suggest.

Except set_val which was rename and exported to __dt_set_cell, nothing
has changed. All the functions are new.

> 
> Are any of these just sync'd from Linux?

Most of them.

> On Fri, 2013-08-16 at 22:05 +0100, Julien Grall wrote:
>> @@ -295,11 +341,29 @@ struct dt_device_node *dt_find_compatible_node(struct dt_device_node *from,
>>  /**
>>   * Find a property with a given name for a given node
>>   * and return the value.
>> - */
>> +  */
> 
> Oops.
> 
>>  const void *dt_get_property(const struct dt_device_node *np,
>>                              const char *name, u32 *lenp);
>>  
>>  /**
>> + * 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
>> + * sucess, -EINVAL if the property does not exist, -ENODATA if property
> 
> success
> 
>> + * 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 modifed only if a valid string can be decoded.
> 
> modified
> 
>> + */
>> +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
>>   * the device's "compatible" property
>>   */
>> @@ -433,4 +497,71 @@ 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 serie of cells
> 
> series
> 
>> + *
>> + * @cellp: Pointer to cells
>> + *
>> + * 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 serie 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 serie of cells and update cellp to point to the
> 
> series
> 
>> + * cell just after.
>> + */
>> +void dt_set_range(__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:
>> + */
> 
> 


-- 
Julien Grall