[PATCH 1/1] of: add dma-mask binding
From: Rob Herring <hidden>
Date: 2012-03-07 16:59:21
Also in:
linux-devicetree
On 03/07/2012 05:26 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
quoted hunk
This will allow each device to specify its dma-mask The microblaze architecture hook is keep temporary if no dma-mask is specified int the DT Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <redacted> --- drivers/of/platform.c | 26 +++++++++++++++++++++++++- 1 files changed, 25 insertions(+), 1 deletions(-)diff --git a/drivers/of/platform.c b/drivers/of/platform.c index cae9477..bb22194 100644 --- a/drivers/of/platform.c +++ b/drivers/of/platform.c@@ -121,6 +121,26 @@ void of_device_make_bus_id(struct device *dev) dev_set_name(dev, "%s.%d", node->name, magic - 1); } +static u64* of_get_dma_mask(struct device_node *np) +{ + const __be32 *prop; + int len; + u64 *dma_mask; + + prop = of_get_property(np, "dma-mask", &len);
This would need some documentation. There is already "dma-ranges" defined for OF which nay do what's needed.
+ + if (!prop) + return NULL; + + dma_mask = kzalloc(sizeof(u64), GFP_KERNEL);
This seems kind of wasteful for 1 u64.
quoted hunk
+ if (!dma_mask) + return NULL; + + *dma_mask = of_read_number(prop, len / 4); + + return dma_mask; +} + /** * of_device_alloc - Allocate and initialize an of_device * @np: device node to assign to device@@ -161,10 +181,14 @@ struct platform_device *of_device_alloc(struct device_node *np, WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq); } + dev->dev.dma_mask = of_get_dma_mask(np); dev->dev.of_node = of_node_get(np); + #if defined(CONFIG_MICROBLAZE) - dev->dev.dma_mask = &dev->archdata.dma_mask;
And doing it this way for didn't get a warm reception either: http://lists.ozlabs.org/pipermail/devicetree-discuss/2011-April/005285.html Do you really need this to be something other than ~0UL and if so does it need to be per device or system wide? You can solve this with bus notifiers in your at91 code. Here's an example which I did (but no longer need): static u64 highbank_dma_mask = DMA_BIT_MASK(32); static int highbank_platform_notifier(struct notifier_block *nb, unsigned long event, void *__dev) { struct device *dev = __dev; if (event != BUS_NOTIFY_ADD_DEVICE) return NOTIFY_DONE; if (of_device_is_compatible(dev->of_node, "calxeda,hb-nfc")) dev->dma_mask = &highbank_dma_mask; else return NOTIFY_DONE; return NOTIFY_OK; } static struct notifier_block highbank_platform_nb = { .notifier_call = highbank_platform_notifier, }; int highbank_devices_init(void) { return bus_register_notifier(&platform_bus_type, &highbank_platform_nb); } Rob
+ if (!dev->dev.dma_mask) + dev->dev.dma_mask = &dev->archdata.dma_mask; #endif + dev->dev.parent = parent; if (bus_id)