From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julien Grall Subject: Re: [PATCH V1 09/29] xen/dts: Add new helpers to use the device tree Date: Mon, 09 Sep 2013 10:38:31 +0100 Message-ID: <522D9717.7090703@linaro.org> References: <1377701263-3319-1-git-send-email-julien.grall@linaro.org> <1377701263-3319-10-git-send-email-julien.grall@linaro.org> <1378485067.14745.160.camel@kazak.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1378485067.14745.160.camel@kazak.uk.xensource.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian Campbell Cc: stefano.stabellini@eu.citrix.com, andre.przywara@linaro.org, patches@linaro.org, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 09/06/2013 05:31 PM, Ian Campbell wrote: > On Wed, 2013-08-28 at 15:47 +0100, Julien Grall wrote: >> 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 >> - for_each_child > > This seems too generic. Perhaps dt_for_each_child or for_each_dt_child? Right, I will rename the function to 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 >> >> --- >> Changes in v2: >> - Update commit message >> - Add for_each_child >> - Add dt_get_range >> - Update documentation >> - Typoes >> --- >> 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 07a19ac..833d67d 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; >> + 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 7cbf736..fa4f314 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) strcasecmp((s1), (s2)) >> #define dt_compat_cmp(s1, s2) strcasecmp((s1), (s2)) >> >> @@ -242,6 +256,9 @@ struct dt_device_node * __init dt_find_interrupt_controller(const char *compat); >> #define for_each_device_node(dt, dn) \ >> for ( dn = dt; dn != NULL; dn = dn->allnext ) >> >> +#define 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 : ""; >> @@ -262,6 +293,18 @@ static inline const char *dt_node_name(const struct dt_device_node *np) >> return (np && np->name) ? np->name : ""; >> } >> >> +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: >> + */ > > -- Julien Grall