@@ -129,6 +129,16 @@ config TPL_DM_INLINE_OFNODE
This applies to several ofnode functions (see ofnode.h) which are
seldom used. Inlining them can help reduce code size.
+config DM_DMA
+ bool "Support per-device DMA constraints"
+ depends on DM
+ default n
+ help
+ Enable this to extract per-device DMA constraints, only supported on
+ device-tree systems for now. This is needed in order translate
+ addresses on systems where different buses have different views of
+ the physical address space.
+
config REGMAP
bool "Support register maps"
depends on DM
@@ -421,6 +421,43 @@ fail:
return ret;
}
+/**
+ * device_get_dma_constraints() - Populate device's DMA constraints
+ *
+ * Gets a device's DMA constraints from firmware. This information is later
+ * used by drivers to translate physcal addresses to the device's bus address
+ * space. For now only device-tree is supported.
+ *
+ * @dev: Pointer to target device
+ * Return: 0 if OK or if no DMA constraints were found, error otherwise
+ */
+static int device_get_dma_constraints(struct udevice *dev)
+{
+ struct udevice *parent = dev->parent;
+ phys_addr_t cpu = 0;
+ dma_addr_t bus = 0;
+ u64 size = 0;
+ int ret;
+
+ if (!CONFIG_IS_ENABLED(DM_DMA) || !parent || !dev_has_ofnode(parent))
+ return 0;
+
+ /*
+ * We start parsing for dma-ranges from the device's bus node. This is
+ * specially important on nested buses.
+ */
+ ret = dev_get_dma_range(parent, &cpu, &bus, &size);
+ /* Don't return an error if no 'dma-ranges' were found */
+ if (ret && ret != -ENOENT) {
+ dm_warn("%s: failed to get DMA range, %d\n", dev->name, ret);
+ return ret;
+ }
+
+ dev_set_dma_offset(dev, cpu - bus);
+
+ return 0;
+}
+
int device_probe(struct udevice *dev)
{
const struct driver *drv;
@@ -474,6 +511,10 @@ int device_probe(struct udevice *dev)
goto fail;
}
+ ret = device_get_dma_constraints(dev);
+ if (ret)
+ goto fail;
+
ret = uclass_pre_probe_device(dev);
if (ret)
goto fail;
@@ -148,6 +148,8 @@ enum {
* When CONFIG_DEVRES is enabled, devm_kmalloc() and friends will
* add to this list. Memory so-allocated will be freed
* automatically when the device is removed / unbound
+ * @dma_offset: Offset between the physical address space (CPU's) and the
+ * device's bus address space
*/
struct udevice {
const struct driver *driver;
@@ -172,6 +174,9 @@ struct udevice {
#ifdef CONFIG_DEVRES
struct list_head devres_head;
#endif
+#if CONFIG_IS_ENABLED(DM_DMA)
+ ulong dma_offset;
+#endif
};
/* Maximum sequence number supported */
@@ -213,6 +218,14 @@ static inline ofnode dev_ofnode(const struct udevice *dev)
/* Returns non-zero if the device is active (probed and not removed) */
#define device_active(dev) (dev_get_flags(dev) & DM_FLAG_ACTIVATED)
+#if CONFIG_IS_ENABLED(DM_DMA)
+#define dev_set_dma_offset(_dev, _offset) _dev->dma_offset = _offset
+#define dev_get_dma_offset(_dev) _dev->dma_offset
+#else
+#define dev_set_dma_offset(_dev, _offset)
+#define dev_get_dma_offset(_dev) 0
+#endif
+
static inline int dev_of_offset(const struct udevice *dev)
{
#if !CONFIG_IS_ENABLED(OF_PLATDATA)