Hi Thierry,
On 18 August 2014 01:16, Thierry Reding thierry.reding@gmail.com wrote:
From: Thierry Reding treding@nvidia.com
Add the fdt_get_resource() and fdt_get_named_resource() functions which can be used to parse resources (memory regions) from an FDT. A helper to compute the size of a region is also provided.
Signed-off-by: Thierry Reding treding@nvidia.com
include/fdtdec.h | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ lib/fdtdec.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 91 insertions(+)
diff --git a/include/fdtdec.h b/include/fdtdec.h index 856e6cf766de..e9091eee6bae 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -40,6 +40,23 @@ struct fdt_memory { fdt_addr_t end; };
+/* information about a resource */
Please add comments, e.g. that end is inclusive.
+struct fdt_resource {
fdt_addr_t start;fdt_addr_t end;+};
+/**
- Compute the size of a resource.
- @param res the resource to operate on
- @return the size of the resource
- */
+static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res) +{
return res->end - res->start + 1;+}
/**
- Compat types that we know about and for which we might have drivers.
- Each is named COMPAT_<dir>_<filename> where <dir> is the directory
@@ -583,4 +600,35 @@ struct fmap_entry { */ int fdtdec_read_fmap_entry(const void *blob, int node, const char *name, struct fmap_entry *entry);
+/**
- Obtain an indexed resource from a device property.
- @param fdt FDT blob
- @param node node to examine
- @param property name of the property to parse
- @param index index of the resource to retrieve
- @param res returns the resource
- @return 0 if ok, negative on error
- */
+int fdt_get_resource(const void *fdt, int node, const char *property,
unsigned int index, struct fdt_resource *res);+/**
- Obtain a named resource from a device property.
- Look up the index of the name in a list of strings and return the resource
- at that index.
- @param fdt FDT blob
- @param node node to examine
- @param property name of the property to parse
- @param names name of the property to obtain the match the name to
- @param name the name of the entry to look up
These two parameters are confusing. Perhaps rename names to something better?
- @param res returns the resource
- */
+int fdt_get_named_resource(const void *fdt, int node, const char *property,
const char *names, const char *name,struct fdt_resource *res);#endif diff --git a/lib/fdtdec.c b/lib/fdtdec.c index eb5aa20526fd..fbfae4a7cbaf 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -691,4 +691,47 @@ int fdtdec_read_fmap_entry(const void *blob, int node, const char *name,
return 0;}
+int fdt_get_resource(const void *fdt, int node, const char *property,
unsigned int index, struct fdt_resource *res)
s/index/find_index/
+{
const fdt32_t *ptr, *end;unsigned int i = 0;int na, ns, len;na = fdt_n_addr_cells(fdt, node);ns = fdt_n_size_cells(fdt, node);ptr = fdt_getprop(fdt, node, property, &len);if (!ptr)return len;end = ptr + len / 4;
sizeof(*ptr) might be better than 4.
while (ptr + na + ns <= end) {if (i == index) {res->start = fdt_addr_to_cpu(*ptr);
This doesn't deal with 64-bit addresses. There is a half-hearted attempt with fdt_addr_t, but I wonder if we need a helper function like fdt_get_addr(ptr, num_cells)?
res->end = res->start + fdt_size_to_cpu(ptr[na]) - 1;return 0;}ptr += na + ns;i++;}return -FDT_ERR_NOTFOUND;+}
+int fdt_get_named_resource(const void *fdt, int node, const char *property,
const char *names, const char *name,struct fdt_resource *res)+{
int index;index = fdt_get_string_index(fdt, node, names, name);if (index < 0)return index;return fdt_get_resource(fdt, node, property, index, res);+}
#endif
2.0.4
Regards, Simon