| Message ID | 20170422173519.5782-2-bjorn.andersson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC,1/3] dt-binding: soc: qcom: Add binding for RFSA | expand |
On 04/22/17 10:35, Bjorn Andersson wrote: > In some cases drivers referencing a reserved-memory region might want to > remap the entire region, but when defining the reserved-memory by "size" > the client driver has no means to know the associated base address of > the reserved memory region. > > This patch adds an accessor for such drivers to acquire a handle to > their associated reserved-memory for this purpose. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > > I would have preferred if we could provide a mechanism for drivers to find the > reserved_mem of their own device_node, but without a phandle I have not been > able to figure out a sane way to make the match. > > Suggestions are very welcome. > > drivers/of/of_reserved_mem.c | 26 ++++++++++++++++++++++++++ > include/linux/of_reserved_mem.h | 8 ++++++++ > 2 files changed, 34 insertions(+) > > diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c > index d507c3569a88..aa69c9590a5c 100644 > --- a/drivers/of/of_reserved_mem.c > +++ b/drivers/of/of_reserved_mem.c > @@ -397,3 +397,29 @@ void of_reserved_mem_device_release(struct device *dev) > rmem->ops->device_release(rmem, dev); > } > EXPORT_SYMBOL_GPL(of_reserved_mem_device_release); > + > +/** > + * of_get_reserved_mem_by_idx() - acquire reserved_mem from memory-region > + * @np: node pointer containing the "memory-region" > + * @idx: index within memory-region > + * > + * This function allows drivers to acquire a reference to the reserved_mem > + * struct which is referenced by their memory-region. > + * > + * Returns a reserved_mem reference, or NULL on error. > + */ > +struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, int idx) > +{ > + struct device_node *target; > + struct reserved_mem *rmem; > + > + target = of_parse_phandle(np, "memory-region", idx); > + if (!target) > + return NULL; > + > + rmem = __find_rmem(target); > + of_node_put(target); > + > + return rmem; > +} > +EXPORT_SYMBOL_GPL(of_get_reserved_mem_by_idx); > diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h > index f8e1992d6423..a9abbe7dd3de 100644 > --- a/include/linux/of_reserved_mem.h > +++ b/include/linux/of_reserved_mem.h > @@ -34,6 +34,8 @@ int of_reserved_mem_device_init_by_idx(struct device *dev, > struct device_node *np, int idx); > void of_reserved_mem_device_release(struct device *dev); > > +struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, int idx); > + > int early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, > phys_addr_t align, > phys_addr_t start, > @@ -52,6 +54,12 @@ static inline int of_reserved_mem_device_init_by_idx(struct device *dev, > } > static inline void of_reserved_mem_device_release(struct device *pdev) { } > > +static inline struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, > + int idx); > +{ > + return NULL; > +} > + > static inline void fdt_init_reserved_mem(void) { } > static inline void fdt_reserved_mem_save_node(unsigned long node, > const char *uname, phys_addr_t base, phys_addr_t size) { } > Reviewed-by: Frank Rowand <frank.rowand@sony.com> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index d507c3569a88..aa69c9590a5c 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -397,3 +397,29 @@ void of_reserved_mem_device_release(struct device *dev) rmem->ops->device_release(rmem, dev); } EXPORT_SYMBOL_GPL(of_reserved_mem_device_release); + +/** + * of_get_reserved_mem_by_idx() - acquire reserved_mem from memory-region + * @np: node pointer containing the "memory-region" + * @idx: index within memory-region + * + * This function allows drivers to acquire a reference to the reserved_mem + * struct which is referenced by their memory-region. + * + * Returns a reserved_mem reference, or NULL on error. + */ +struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, int idx) +{ + struct device_node *target; + struct reserved_mem *rmem; + + target = of_parse_phandle(np, "memory-region", idx); + if (!target) + return NULL; + + rmem = __find_rmem(target); + of_node_put(target); + + return rmem; +} +EXPORT_SYMBOL_GPL(of_get_reserved_mem_by_idx); diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h index f8e1992d6423..a9abbe7dd3de 100644 --- a/include/linux/of_reserved_mem.h +++ b/include/linux/of_reserved_mem.h @@ -34,6 +34,8 @@ int of_reserved_mem_device_init_by_idx(struct device *dev, struct device_node *np, int idx); void of_reserved_mem_device_release(struct device *dev); +struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, int idx); + int early_init_dt_alloc_reserved_memory_arch(phys_addr_t size, phys_addr_t align, phys_addr_t start, @@ -52,6 +54,12 @@ static inline int of_reserved_mem_device_init_by_idx(struct device *dev, } static inline void of_reserved_mem_device_release(struct device *pdev) { } +static inline struct reserved_mem *of_get_reserved_mem_by_idx(struct device_node *np, + int idx); +{ + return NULL; +} + static inline void fdt_init_reserved_mem(void) { } static inline void fdt_reserved_mem_save_node(unsigned long node, const char *uname, phys_addr_t base, phys_addr_t size) { }
In some cases drivers referencing a reserved-memory region might want to remap the entire region, but when defining the reserved-memory by "size" the client driver has no means to know the associated base address of the reserved memory region. This patch adds an accessor for such drivers to acquire a handle to their associated reserved-memory for this purpose. Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> --- I would have preferred if we could provide a mechanism for drivers to find the reserved_mem of their own device_node, but without a phandle I have not been able to figure out a sane way to make the match. Suggestions are very welcome. drivers/of/of_reserved_mem.c | 26 ++++++++++++++++++++++++++ include/linux/of_reserved_mem.h | 8 ++++++++ 2 files changed, 34 insertions(+) -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html