2012-11-02 10:46:28

by Srinivas KANDAGATLA

[permalink] [raw]
Subject: [RFC PATCH 3.7.0-rc2] dt/platform: insert resources correctly into resource tree

From: Srinivas Kandagatla <[email protected]>

This patch add new code to correctly add resources into platform device.
Issue with the existing code was the resources are added as flat entry
without creating any tree, this is very much different to what non-dt
platform code does.

With this patch the resources appear correctly as tree in /proc/iomem,
without this patch the resources in /proc/iomem appear as single entry.

i2c example in /proc/iomem:

With-patch:

fed41000-fed4110f : /soc/i2c-stm@fed41000
fed41000-fed4110f : i2c

Without patch:
fed41000-fed4110f : i2c

Signed-off-by: Srinivas Kandagatla <[email protected]>
---
Hi All,
Recently I noticed that appearance of /proc/iomem ouput changed
when I started using device trees and the reason for this was
the of-plaform code was not adding resources in same way as
non-dt platform code does.

Do you have any reason for not doing it the same way as non-dt platform code?

This patch is a fixup to that issue.

Comment?
thanks,
srini

drivers/of/platform.c | 23 +++++++++++++++++++++++
1 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index b80891b..f43922c 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -203,6 +203,7 @@ struct platform_device *of_platform_device_create_pdata(
struct device *parent)
{
struct platform_device *dev;
+ int i;

if (!of_device_is_available(np))
return NULL;
@@ -218,6 +219,28 @@ struct platform_device *of_platform_device_create_pdata(
dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;

+ for (i = 0; i < dev->num_resources; i++) {
+ struct resource *p, *r = &dev->resource[i];
+
+ if (r->name == NULL)
+ r->name = dev_name(&dev->dev);
+
+ p = r->parent;
+ if (!p) {
+ if (resource_type(r) == IORESOURCE_MEM)
+ p = &iomem_resource;
+ else if (resource_type(r) == IORESOURCE_IO)
+ p = &ioport_resource;
+ }
+
+ if (p && insert_resource(p, r)) {
+ pr_err("%s: failed to claim resource %d\n",
+ dev_name(&dev->dev), i);
+ platform_device_put(dev);
+ return NULL;
+ }
+ }
+
/* We do not fill the DMA ops for platform devices by default.
* This is currently the responsibility of the platform code
* to do such, possibly using a device notifier
--
1.7.0.4


2012-11-15 13:11:40

by Grant Likely

[permalink] [raw]
Subject: Re: [RFC PATCH 3.7.0-rc2] dt/platform: insert resources correctly into resource tree

On Fri, 2 Nov 2012 10:46:19 +0000, Srinivas KANDAGATLA <[email protected]> wrote:
> From: Srinivas Kandagatla <[email protected]>
>
> This patch add new code to correctly add resources into platform device.
> Issue with the existing code was the resources are added as flat entry
> without creating any tree, this is very much different to what non-dt
> platform code does.
>
> With this patch the resources appear correctly as tree in /proc/iomem,
> without this patch the resources in /proc/iomem appear as single entry.
>
> i2c example in /proc/iomem:
>
> With-patch:
>
> fed41000-fed4110f : /soc/i2c-stm@fed41000
> fed41000-fed4110f : i2c
>
> Without patch:
> fed41000-fed4110f : i2c
>
> Signed-off-by: Srinivas Kandagatla <[email protected]>

Yes, that is a problem that should be fixed.
Although it seems to me that some powerpc platforms will break due to
nodes with overlapping ranges. That will need to be tested.

I also don't like the duplication of code from platform_device_add().
Does something like this work for you instead? I might need to add an
exception to fallback onto of_device_add if the resource regions
overlay. Or modify platform_device_add() to complain about overlaps, but
not fail when on PowerPC.

g.

---

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 72c776f..2edf831 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -283,7 +283,7 @@ int platform_device_add(struct platform_device *pdev)
if (!pdev)
return -EINVAL;

- if (!pdev->dev.parent)
+ if (!pdev->dev.parent && !pdev->dev.of_node)
pdev->dev.parent = &platform_bus;

pdev->dev.bus = &platform_bus_type;
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index b80891b..fb9cbad 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -214,16 +214,22 @@ struct platform_device *of_platform_device_create_pdata(
#if defined(CONFIG_MICROBLAZE)
dev->archdata.dma_mask = 0xffffffffUL;
#endif
+ dev->name = dev_name(&dev->dev);
dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
- dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;
+ dev->dev.id = PLATFORM_DEVID_NONE;
+ /* device_add will assume that this device is on the same node as
+ * the parent. If there is no parent defined, set the node
+ * explicitly */
+ if (!parent)
+ set_dev_node(&dev->dev, of_node_to_nid(np));

/* We do not fill the DMA ops for platform devices by default.
* This is currently the responsibility of the platform code
* to do such, possibly using a device notifier
*/

- if (of_device_add(dev) != 0) {
+ if (platform_device_add(dev)) {
platform_device_put(dev);
return NULL;
}


> ---
> Hi All,
> Recently I noticed that appearance of /proc/iomem ouput changed
> when I started using device trees and the reason for this was
> the of-plaform code was not adding resources in same way as
> non-dt platform code does.
>
> Do you have any reason for not doing it the same way as non-dt platform code?
>
> This patch is a fixup to that issue.
>
> Comment?
> thanks,
> srini
>
> drivers/of/platform.c | 23 +++++++++++++++++++++++
> 1 files changed, 23 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index b80891b..f43922c 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -203,6 +203,7 @@ struct platform_device *of_platform_device_create_pdata(
> struct device *parent)
> {
> struct platform_device *dev;
> + int i;
>
> if (!of_device_is_available(np))
> return NULL;
> @@ -218,6 +219,28 @@ struct platform_device *of_platform_device_create_pdata(
> dev->dev.bus = &platform_bus_type;
> dev->dev.platform_data = platform_data;
>
> + for (i = 0; i < dev->num_resources; i++) {
> + struct resource *p, *r = &dev->resource[i];
> +
> + if (r->name == NULL)
> + r->name = dev_name(&dev->dev);
> +
> + p = r->parent;
> + if (!p) {
> + if (resource_type(r) == IORESOURCE_MEM)
> + p = &iomem_resource;
> + else if (resource_type(r) == IORESOURCE_IO)
> + p = &ioport_resource;
> + }
> +
> + if (p && insert_resource(p, r)) {
> + pr_err("%s: failed to claim resource %d\n",
> + dev_name(&dev->dev), i);
> + platform_device_put(dev);
> + return NULL;
> + }
> + }
> +
> /* We do not fill the DMA ops for platform devices by default.
> * This is currently the responsibility of the platform code
> * to do such, possibly using a device notifier
> --
> 1.7.0.4
>

--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.

2012-11-15 18:41:56

by Srinivas KANDAGATLA

[permalink] [raw]
Subject: Re: [RFC PATCH 3.7.0-rc2] dt/platform: insert resources correctly into resource tree

On 15/11/12 13:11, Grant Likely wrote:
> On Fri, 2 Nov 2012 10:46:19 +0000, Srinivas KANDAGATLA <[email protected]> wrote:
>> From: Srinivas Kandagatla <[email protected]>
>>
>> This patch add new code to correctly add resources into platform device.
>> Issue with the existing code was the resources are added as flat entry
>> without creating any tree, this is very much different to what non-dt
>> platform code does.
>>
>> With this patch the resources appear correctly as tree in /proc/iomem,
>> without this patch the resources in /proc/iomem appear as single entry.
>>
>> i2c example in /proc/iomem:
>>
>> With-patch:
>>
>> fed41000-fed4110f : /soc/i2c-stm@fed41000
>> fed41000-fed4110f : i2c
>>
>> Without patch:
>> fed41000-fed4110f : i2c
>>
>> Signed-off-by: Srinivas Kandagatla <[email protected]>
> Yes, that is a problem that should be fixed.
> Although it seems to me that some powerpc platforms will break due to
> nodes with overlapping ranges. That will need to be tested.
>
> I also don't like the duplication of code from platform_device_add().
I agree, I don't like the duplication too.
> Does something like this work for you instead?
Yes, it works for me and I have tested your patch.

Tested-by: Srinivas Kandagatla<[email protected]>

> I might need to add an
> exception to fallback onto of_device_add if the resource regions
> overlay. Or modify platform_device_add() to complain about overlaps, but
> not fail when on PowerPC.
>
> g.
>
> ---
>
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index 72c776f..2edf831 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -283,7 +283,7 @@ int platform_device_add(struct platform_device *pdev)
> if (!pdev)
> return -EINVAL;
>
> - if (!pdev->dev.parent)
> + if (!pdev->dev.parent && !pdev->dev.of_node)
> pdev->dev.parent = &platform_bus;
>
> pdev->dev.bus = &platform_bus_type;
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index b80891b..fb9cbad 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -214,16 +214,22 @@ struct platform_device *of_platform_device_create_pdata(
> #if defined(CONFIG_MICROBLAZE)
> dev->archdata.dma_mask = 0xffffffffUL;
> #endif
> + dev->name = dev_name(&dev->dev);
> dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
> - dev->dev.bus = &platform_bus_type;
> dev->dev.platform_data = platform_data;
> + dev->dev.id = PLATFORM_DEVID_NONE;
> + /* device_add will assume that this device is on the same node as
> + * the parent. If there is no parent defined, set the node
> + * explicitly */
> + if (!parent)
> + set_dev_node(&dev->dev, of_node_to_nid(np));
>
> /* We do not fill the DMA ops for platform devices by default.
> * This is currently the responsibility of the platform code
> * to do such, possibly using a device notifier
> */
>
> - if (of_device_add(dev) != 0) {
> + if (platform_device_add(dev)) {
> platform_device_put(dev);
> return NULL;
> }
>
>
>> ---
>> Hi All,
>> Recently I noticed that appearance of /proc/iomem ouput changed
>> when I started using device trees and the reason for this was
>> the of-plaform code was not adding resources in same way as
>> non-dt platform code does.
>>
>> Do you have any reason for not doing it the same way as non-dt platform code?
>>
>> This patch is a fixup to that issue.
>>
>> Comment?
>> thanks,
>> srini
>>
>> drivers/of/platform.c | 23 +++++++++++++++++++++++
>> 1 files changed, 23 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
>> index b80891b..f43922c 100644
>> --- a/drivers/of/platform.c
>> +++ b/drivers/of/platform.c
>> @@ -203,6 +203,7 @@ struct platform_device *of_platform_device_create_pdata(
>> struct device *parent)
>> {
>> struct platform_device *dev;
>> + int i;
>>
>> if (!of_device_is_available(np))
>> return NULL;
>> @@ -218,6 +219,28 @@ struct platform_device *of_platform_device_create_pdata(
>> dev->dev.bus = &platform_bus_type;
>> dev->dev.platform_data = platform_data;
>>
>> + for (i = 0; i < dev->num_resources; i++) {
>> + struct resource *p, *r = &dev->resource[i];
>> +
>> + if (r->name == NULL)
>> + r->name = dev_name(&dev->dev);
>> +
>> + p = r->parent;
>> + if (!p) {
>> + if (resource_type(r) == IORESOURCE_MEM)
>> + p = &iomem_resource;
>> + else if (resource_type(r) == IORESOURCE_IO)
>> + p = &ioport_resource;
>> + }
>> +
>> + if (p && insert_resource(p, r)) {
>> + pr_err("%s: failed to claim resource %d\n",
>> + dev_name(&dev->dev), i);
>> + platform_device_put(dev);
>> + return NULL;
>> + }
>> + }
>> +
>> /* We do not fill the DMA ops for platform devices by default.
>> * This is currently the responsibility of the platform code
>> * to do such, possibly using a device notifier
>> --
>> 1.7.0.4
>>