From mboxrd@z Thu Jan 1 00:00:00 1970 From: jonathan.austin@arm.com (Jonathan Austin) Date: Wed, 12 Jun 2013 11:10:49 +0100 Subject: [PATCH] of: Add missing node iteration stubs for disabled CONFIG_OF In-Reply-To: <20130611215147.199B13E0D8D@localhost> References: <1362860154-3089-1-git-send-email-tomasz.figa@gmail.com> <5159F9E6.50508@gmail.com> <51B74EDF.2090504@arm.com> <20130611215147.199B13E0D8D@localhost> Message-ID: <51B84929.4050802@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/06/13 22:51, Grant Likely wrote: > On Tue, 11 Jun 2013 17:22:55 +0100, Jonathan Austin wrote: >> Hi Rob, Thomasz, >> >> (dredging up an oldish thread as I just ran in to this issue) >> >> On 01/04/13 22:19, Rob Herring wrote: >>> On 03/09/2013 02:15 PM, Tomasz Figa wrote: >>>> This patch moves several for_each macros out of the #ifdef CONFIG_OF >>>> block and adds inline stubs for functions used by these macros, compiled >>>> conditionally when CONFIG_OF is not enabled. >>>> >>>> This eliminates the need to explicitly check for CONFIG_OF in driver >>>> code using mentioned functions and macros. >>> >>> Do you have some users of this? >> >> I do! >> >> Or at least I might. >> >> I'm not certain as perhaps the fix to what I describe below is to add >> dependencies on CONFIG_OF - it isn't clear to me either way: >> >> With both psci and arch_timers (CONFIG_ARM_PSCI, CONFIG_ARM_ARCH_TIMER) >> and without CONFIG_OF we get a build failure because we lack the definition >> of of_find_matching_node(): >> >> eg: >> arch/arm/kernel/psci.c:167:2: error: implicit declaration of function ???of_find_matching_node??? [-Werror=implicit-function-declaration] >> >> The same happens with arm_arch_timer.c (well, there's a patch required to >> include linux/of.h first, after which Thomasz's patch is relevant). > > That code path is completely broken if CONFIG_OF is not set. psci_init() > is nothing but calls to CONFIG_OF infrastructure! I think that code Well, it looks like the intention of that code was to just behave like there was no relevant node in the case the CONFIG_OF was disabled: np = of_find_matching_node(NULL, psci_of_match); if (!np) return 0; If of_find_matching() node behaved like of_match_node() then nothing would be 'broken' per se, but we would have a bunch of useless code compiled in to our kernel. > needs to depend on CONFIG_OF, or at least be wrapped with > "if (IS_ENABLED(CONFIG_OF))" if there are still usable parts when > CONFIG_OF is disabled. Frankly I don't see that as being a real concern. Indeed, despite the clarification above, I think it'd be fine to not build these without CONFIG_OF. I'm happy to submit a patches to add dependencies on CONFIG_OF for ARM_ARCH_TIMER and ARM_PSCI - I don't think either of those will get any complaints because as you say, neither makes very much sense without a DT to specify them. Thanks, Jonny > > That said, Arnd has posted a patch that moves at least some of the function > prototypes out from under the #ifdef block so that GCC can do syntax > checking on disabled code. That overlaps a bit with this patch. > > Regardless, I'm not going to apply it without a legitimate (as opposed > to theoretical) user. > > g. > >> So, I guess the question is whether we should expect PSCI and ARM_ARCH_TIMER >> to depend on CONFIG_OF, or whether we'd like them to fail gracefully in the >> case that we *don't* have CONFIG_OF. I think the current situation is broken >> either way... >> >> Thoughts? >> >> Jonny >> >>> >>> Rob >>> >>>> >>>> Signed-off-by: Tomasz Figa >>>> --- >>>> include/linux/of.h | 92 +++++++++++++++++++++++++++++++++++++----------------- >>>> 1 file changed, 63 insertions(+), 29 deletions(-) >>>> >>>> diff --git a/include/linux/of.h b/include/linux/of.h >>>> index a0f1292..7a736b8 100644 >>>> --- a/include/linux/of.h >>>> +++ b/include/linux/of.h >>>> @@ -86,6 +86,31 @@ static inline struct device_node *of_node_get(struct device_node *node) >>>> static inline void of_node_put(struct device_node *node) { } >>>> #endif /* !CONFIG_OF_DYNAMIC */ >>>> >>>> +#define for_each_node_by_name(dn, name) \ >>>> + for (dn = of_find_node_by_name(NULL, name); dn; \ >>>> + dn = of_find_node_by_name(dn, name)) >>>> +#define for_each_node_by_type(dn, type) \ >>>> + for (dn = of_find_node_by_type(NULL, type); dn; \ >>>> + dn = of_find_node_by_type(dn, type)) >>>> +#define for_each_compatible_node(dn, type, compatible) \ >>>> + for (dn = of_find_compatible_node(NULL, type, compatible); dn; \ >>>> + dn = of_find_compatible_node(dn, type, compatible)) >>>> +#define for_each_matching_node(dn, matches) \ >>>> + for (dn = of_find_matching_node(NULL, matches); dn; \ >>>> + dn = of_find_matching_node(dn, matches)) >>>> +#define for_each_matching_node_and_match(dn, matches, match) \ >>>> + for (dn = of_find_matching_node_and_match(NULL, matches, match); \ >>>> + dn; dn = of_find_matching_node_and_match(dn, matches, match)) >>>> +#define for_each_child_of_node(parent, child) \ >>>> + for (child = of_get_next_child(parent, NULL); child != NULL; \ >>>> + child = of_get_next_child(parent, child)) >>>> +#define for_each_available_child_of_node(parent, child) \ >>>> + for (child = of_get_next_available_child(parent, NULL); child != NULL; \ >>>> + child = of_get_next_available_child(parent, child)) >>>> +#define for_each_node_with_property(dn, prop_name) \ >>>> + for (dn = of_find_node_with_property(NULL, prop_name); dn; \ >>>> + dn = of_find_node_with_property(dn, prop_name)) >>>> + >>>> #ifdef CONFIG_OF >>>> >>>> /* Pointer for first entry in chain of all nodes. */ >>>> @@ -167,19 +192,10 @@ static inline const char *of_node_full_name(const struct device_node *np) >>>> >>>> extern struct device_node *of_find_node_by_name(struct device_node *from, >>>> const char *name); >>>> -#define for_each_node_by_name(dn, name) \ >>>> - for (dn = of_find_node_by_name(NULL, name); dn; \ >>>> - dn = of_find_node_by_name(dn, name)) >>>> extern struct device_node *of_find_node_by_type(struct device_node *from, >>>> const char *type); >>>> -#define for_each_node_by_type(dn, type) \ >>>> - for (dn = of_find_node_by_type(NULL, type); dn; \ >>>> - dn = of_find_node_by_type(dn, type)) >>>> extern struct device_node *of_find_compatible_node(struct device_node *from, >>>> const char *type, const char *compat); >>>> -#define for_each_compatible_node(dn, type, compatible) \ >>>> - for (dn = of_find_compatible_node(NULL, type, compatible); dn; \ >>>> - dn = of_find_compatible_node(dn, type, compatible)) >>>> extern struct device_node *of_find_matching_node_and_match( >>>> struct device_node *from, >>>> const struct of_device_id *matches, >>>> @@ -190,12 +206,6 @@ static inline struct device_node *of_find_matching_node( >>>> { >>>> return of_find_matching_node_and_match(from, matches, NULL); >>>> } >>>> -#define for_each_matching_node(dn, matches) \ >>>> - for (dn = of_find_matching_node(NULL, matches); dn; \ >>>> - dn = of_find_matching_node(dn, matches)) >>>> -#define for_each_matching_node_and_match(dn, matches, match) \ >>>> - for (dn = of_find_matching_node_and_match(NULL, matches, match); \ >>>> - dn; dn = of_find_matching_node_and_match(dn, matches, match)) >>>> extern struct device_node *of_find_node_by_path(const char *path); >>>> extern struct device_node *of_find_node_by_phandle(phandle handle); >>>> extern struct device_node *of_get_parent(const struct device_node *node); >>>> @@ -207,14 +217,6 @@ extern struct device_node *of_get_next_available_child( >>>> >>>> extern struct device_node *of_get_child_by_name(const struct device_node *node, >>>> const char *name); >>>> -#define for_each_child_of_node(parent, child) \ >>>> - for (child = of_get_next_child(parent, NULL); child != NULL; \ >>>> - child = of_get_next_child(parent, child)) >>>> - >>>> -#define for_each_available_child_of_node(parent, child) \ >>>> - for (child = of_get_next_available_child(parent, NULL); child != NULL; \ >>>> - child = of_get_next_available_child(parent, child)) >>>> - >>>> static inline int of_get_child_count(const struct device_node *np) >>>> { >>>> struct device_node *child; >>>> @@ -228,10 +230,6 @@ static inline int of_get_child_count(const struct device_node *np) >>>> >>>> extern struct device_node *of_find_node_with_property( >>>> struct device_node *from, const char *prop_name); >>>> -#define for_each_node_with_property(dn, prop_name) \ >>>> - for (dn = of_find_node_with_property(NULL, prop_name); dn; \ >>>> - dn = of_find_node_with_property(dn, prop_name)) >>>> - >>>> extern struct property *of_find_property(const struct device_node *np, >>>> const char *name, >>>> int *lenp); >>>> @@ -353,13 +351,28 @@ static inline struct device_node *of_find_node_by_name(struct device_node *from, >>>> return NULL; >>>> } >>>> >>>> +static inline struct device_node *of_find_node_by_type(struct device_node *from, >>>> + const char *type) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> static inline bool of_have_populated_dt(void) >>>> { >>>> return false; >>>> } >>>> >>>> -#define for_each_child_of_node(parent, child) \ >>>> - while (0) >>>> +static inline struct device_node *of_get_next_child(const struct device_node *node, >>>> + struct device_node *prev) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> +static inline struct device_node *of_get_next_available_child( >>>> + const struct device_node *node, struct device_node *prev) >>>> +{ >>>> + return NULL; >>>> +} >>>> >>>> static inline struct device_node *of_get_child_by_name( >>>> const struct device_node *node, >>>> @@ -373,6 +386,12 @@ static inline int of_get_child_count(const struct device_node *np) >>>> return 0; >>>> } >>>> >>>> +static inline struct device_node *of_find_node_with_property( >>>> + struct device_node *from, const char *prop_name) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> static inline int of_device_is_compatible(const struct device_node *device, >>>> const char *name) >>>> { >>>> @@ -394,6 +413,21 @@ static inline struct device_node *of_find_compatible_node( >>>> return NULL; >>>> } >>>> >>>> +static inline struct device_node *of_find_matching_node_and_match( >>>> + struct device_node *from, >>>> + const struct of_device_id *matches, >>>> + const struct of_device_id **match) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> +static inline struct device_node *of_find_matching_node( >>>> + struct device_node *from, >>>> + const struct of_device_id *matches) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> static inline int of_property_read_u8_array(const struct device_node *np, >>>> const char *propname, u8 *out_values, size_t sz) >>>> { >>>> >>> >>> >>> _______________________________________________ >>> linux-arm-kernel mailing list >>> linux-arm-kernel at lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >>> >> >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel at lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >