Commit 59ce4039 authored by Marek Szyprowski's avatar Marek Szyprowski Committed by Sylwester Nawrocki

of: reserved_mem: add support for using more than one region for given device

This patch allows device drivers to initialize more than one reserved
memory region assigned to given device. When driver needs to use more
than one reserved memory region, it should allocate child devices and
initialize regions by index for each of its child devices.
Signed-off-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarSylwester Nawrocki <s.nawrocki@samsung.com>
parent 712b617e
...@@ -21,6 +21,7 @@ ...@@ -21,6 +21,7 @@
#include <linux/sizes.h> #include <linux/sizes.h>
#include <linux/of_reserved_mem.h> #include <linux/of_reserved_mem.h>
#include <linux/sort.h> #include <linux/sort.h>
#include <linux/slab.h>
#define MAX_RESERVED_REGIONS 16 #define MAX_RESERVED_REGIONS 16
static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS]; static struct reserved_mem reserved_mem[MAX_RESERVED_REGIONS];
...@@ -289,53 +290,95 @@ static inline struct reserved_mem *__find_rmem(struct device_node *node) ...@@ -289,53 +290,95 @@ static inline struct reserved_mem *__find_rmem(struct device_node *node)
return NULL; return NULL;
} }
struct rmem_assigned_device {
struct device *dev;
struct reserved_mem *rmem;
struct list_head list;
};
static LIST_HEAD(of_rmem_assigned_device_list);
static DEFINE_MUTEX(of_rmem_assigned_device_mutex);
/** /**
* of_reserved_mem_device_init() - assign reserved memory region to given device * of_reserved_mem_device_init_by_idx() - assign reserved memory region to
* given device
* @dev: Pointer to the device to configure
* @np: Pointer to the device_node with 'reserved-memory' property
* @idx: Index of selected region
* *
* This function assign memory region pointed by "memory-region" device tree * This function assigns respective DMA-mapping operations based on reserved
* property to the given device. * memory region specified by 'memory-region' property in @np node to the @dev
* device. When driver needs to use more than one reserved memory region, it
* should allocate child devices and initialize regions by name for each of
* child device.
*
* Returns error code or zero on success.
*/ */
int of_reserved_mem_device_init(struct device *dev) int of_reserved_mem_device_init_by_idx(struct device *dev,
struct device_node *np, int idx)
{ {
struct rmem_assigned_device *rd;
struct device_node *target;
struct reserved_mem *rmem; struct reserved_mem *rmem;
struct device_node *np;
int ret; int ret;
np = of_parse_phandle(dev->of_node, "memory-region", 0); if (!np || !dev)
if (!np) return -EINVAL;
return -ENODEV;
rmem = __find_rmem(np); target = of_parse_phandle(np, "memory-region", idx);
of_node_put(np); if (!target)
return -EINVAL;
rmem = __find_rmem(target);
of_node_put(target);
if (!rmem || !rmem->ops || !rmem->ops->device_init) if (!rmem || !rmem->ops || !rmem->ops->device_init)
return -EINVAL; return -EINVAL;
rd = kmalloc(sizeof(struct rmem_assigned_device), GFP_KERNEL);
if (!rd)
return -ENOMEM;
ret = rmem->ops->device_init(rmem, dev); ret = rmem->ops->device_init(rmem, dev);
if (ret == 0) if (ret == 0) {
rd->dev = dev;
rd->rmem = rmem;
mutex_lock(&of_rmem_assigned_device_mutex);
list_add(&rd->list, &of_rmem_assigned_device_list);
mutex_unlock(&of_rmem_assigned_device_mutex);
dev_info(dev, "assigned reserved memory node %s\n", rmem->name); dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
} else {
kfree(rd);
}
return ret; return ret;
} }
EXPORT_SYMBOL_GPL(of_reserved_mem_device_init); EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_by_idx);
/** /**
* of_reserved_mem_device_release() - release reserved memory device structures * of_reserved_mem_device_release() - release reserved memory device structures
* @dev: Pointer to the device to deconfigure
* *
* This function releases structures allocated for memory region handling for * This function releases structures allocated for memory region handling for
* the given device. * the given device.
*/ */
void of_reserved_mem_device_release(struct device *dev) void of_reserved_mem_device_release(struct device *dev)
{ {
struct reserved_mem *rmem; struct rmem_assigned_device *rd;
struct device_node *np; struct reserved_mem *rmem = NULL;
np = of_parse_phandle(dev->of_node, "memory-region", 0); mutex_lock(&of_rmem_assigned_device_mutex);
if (!np) list_for_each_entry(rd, &of_rmem_assigned_device_list, list) {
return; if (rd->dev == dev) {
rmem = rd->rmem;
rmem = __find_rmem(np); list_del(&rd->list);
of_node_put(np); kfree(rd);
break;
}
}
mutex_unlock(&of_rmem_assigned_device_mutex);
if (!rmem || !rmem->ops || !rmem->ops->device_release) if (!rmem || !rmem->ops || !rmem->ops->device_release)
return; return;
......
#ifndef __OF_RESERVED_MEM_H #ifndef __OF_RESERVED_MEM_H
#define __OF_RESERVED_MEM_H #define __OF_RESERVED_MEM_H
struct device; #include <linux/device.h>
struct of_phandle_args; struct of_phandle_args;
struct reserved_mem_ops; struct reserved_mem_ops;
...@@ -28,14 +29,17 @@ typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem); ...@@ -28,14 +29,17 @@ typedef int (*reservedmem_of_init_fn)(struct reserved_mem *rmem);
_OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn) _OF_DECLARE(reservedmem, name, compat, init, reservedmem_of_init_fn)
#ifdef CONFIG_OF_RESERVED_MEM #ifdef CONFIG_OF_RESERVED_MEM
int of_reserved_mem_device_init(struct device *dev);
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); void of_reserved_mem_device_release(struct device *dev);
void fdt_init_reserved_mem(void); void fdt_init_reserved_mem(void);
void fdt_reserved_mem_save_node(unsigned long node, const char *uname, void fdt_reserved_mem_save_node(unsigned long node, const char *uname,
phys_addr_t base, phys_addr_t size); phys_addr_t base, phys_addr_t size);
#else #else
static inline int of_reserved_mem_device_init(struct device *dev) static inline int of_reserved_mem_device_init_by_idx(struct device *dev,
struct device_node *np, int idx)
{ {
return -ENOSYS; return -ENOSYS;
} }
...@@ -46,4 +50,19 @@ static inline void fdt_reserved_mem_save_node(unsigned long node, ...@@ -46,4 +50,19 @@ static inline void fdt_reserved_mem_save_node(unsigned long node,
const char *uname, phys_addr_t base, phys_addr_t size) { } const char *uname, phys_addr_t base, phys_addr_t size) { }
#endif #endif
/**
* of_reserved_mem_device_init() - assign reserved memory region to given device
* @dev: Pointer to the device to configure
*
* This function assigns respective DMA-mapping operations based on the first
* reserved memory region specified by 'memory-region' property in device tree
* node of the given device.
*
* Returns error code or zero on success.
*/
static inline int of_reserved_mem_device_init(struct device *dev)
{
return of_reserved_mem_device_init_by_idx(dev, dev->of_node, 0);
}
#endif /* __OF_RESERVED_MEM_H */ #endif /* __OF_RESERVED_MEM_H */
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