It's bus specific aspect to map a given device on the bus and
relevant firmware description of its DMA configuration.
So, this change introduces '/dma_configure/' as bus callback
giving flexibility to busses for implementing its own dma
configuration function.
The change eases the addition of new busses w.r.t. adding the dma
configuration functionality.
This patch also updates the PCI, Platform, ACPI and host1x bus to
use new introduced callbacks.
Suggested-by: Christoph Hellwig <[email protected]>
Signed-off-by: Nipun Gupta <[email protected]>
---
- The patches are based on the comments on:
https://patchwork.kernel.org/patch/10259087/
Changes in v2:
- Do not have dma_deconfigure callback
- Have '/dma_common_configure/' API to provide a common DMA
configuration which can be used by busses if it suits them.
- Platform and ACPI bus to use '/dma_common_configure/' in
'/dma_configure/' callback.
- Updated commit message
- Updated pci_dma_configure API with changes suggested by Robin
drivers/amba/bus.c | 7 +++++++
drivers/base/dma-mapping.c | 35 +++++++++++++++--------------------
drivers/base/platform.c | 6 ++++++
drivers/gpu/host1x/bus.c | 9 +++++++++
drivers/pci/pci-driver.c | 32 ++++++++++++++++++++++++++++++++
include/linux/device.h | 4 ++++
include/linux/dma-mapping.h | 1 +
7 files changed, 74 insertions(+), 20 deletions(-)
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 594c228..2fa1e8b 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -20,6 +20,7 @@
#include <linux/sizes.h>
#include <linux/limits.h>
#include <linux/clk/clk-conf.h>
+#include <linux/dma-mapping.h>
#include <asm/irq.h>
@@ -171,6 +172,11 @@ static int amba_pm_runtime_resume(struct device *dev)
}
#endif /* CONFIG_PM */
+static int amba_dma_configure(struct device *dev)
+{
+ return dma_common_configure(dev);
+}
+
static const struct dev_pm_ops amba_pm = {
.suspend = pm_generic_suspend,
.resume = pm_generic_resume,
@@ -194,6 +200,7 @@ struct bus_type amba_bustype = {
.dev_groups = amba_dev_groups,
.match = amba_match,
.uevent = amba_uevent,
+ .dma_configure = amba_dma_configure,
.pm = &amba_pm,
.force_dma = true,
};
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index 3b11835..48f9af0 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -331,38 +331,33 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
#endif
/*
- * Common configuration to enable DMA API use for a device
+ * Common configuration to enable DMA API use for a device.
+ * A bus can use this function in its 'dma_configure' callback, if
+ * suitable for the bus.
*/
-#include <linux/pci.h>
-
-int dma_configure(struct device *dev)
+int dma_common_configure(struct device *dev)
{
- struct device *bridge = NULL, *dma_dev = dev;
enum dev_dma_attr attr;
int ret = 0;
- if (dev_is_pci(dev)) {
- bridge = pci_get_host_bridge_device(to_pci_dev(dev));
- dma_dev = bridge;
- if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
- dma_dev->parent->of_node)
- dma_dev = dma_dev->parent;
- }
-
- if (dma_dev->of_node) {
- ret = of_dma_configure(dev, dma_dev->of_node);
- } else if (has_acpi_companion(dma_dev)) {
- attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
+ if (dev->of_node) {
+ ret = of_dma_configure(dev, dev->of_node);
+ } else if (has_acpi_companion(dev)) {
+ attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
if (attr != DEV_DMA_NOT_SUPPORTED)
ret = acpi_dma_configure(dev, attr);
}
- if (bridge)
- pci_put_host_bridge_device(bridge);
-
return ret;
}
+int dma_configure(struct device *dev)
+{
+ if (dev->bus->dma_configure)
+ return dev->bus->dma_configure(dev);
+
+ return 0;
+}
void dma_deconfigure(struct device *dev)
{
of_dma_deconfigure(dev);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index f1bf7b3..d2d5891 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1130,6 +1130,11 @@ int platform_pm_restore(struct device *dev)
#endif /* CONFIG_HIBERNATE_CALLBACKS */
+static int platform_dma_configure(struct device *dev)
+{
+ return dma_common_configure(dev);
+}
+
static const struct dev_pm_ops platform_dev_pm_ops = {
.runtime_suspend = pm_generic_runtime_suspend,
.runtime_resume = pm_generic_runtime_resume,
@@ -1141,6 +1146,7 @@ struct bus_type platform_bus_type = {
.dev_groups = platform_dev_groups,
.match = platform_match,
.uevent = platform_uevent,
+ .dma_configure = platform_dma_configure,
.pm = &platform_dev_pm_ops,
.force_dma = true,
};
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index 88a3558..fa9896d 100644
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -314,6 +314,14 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
return strcmp(dev_name(dev), drv->name) == 0;
}
+static int host1x_dma_configure(struct device *dev)
+{
+ if (dev->of_node)
+ return of_dma_configure(dev, dev->of_node);
+
+ return 0;
+}
+
static const struct dev_pm_ops host1x_device_pm_ops = {
.suspend = pm_generic_suspend,
.resume = pm_generic_resume,
@@ -326,6 +334,7 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
struct bus_type host1x_bus_type = {
.name = "host1x",
.match = host1x_device_match,
+ .dma_configure = host1x_dma_configure,
.pm = &host1x_device_pm_ops,
.force_dma = true,
};
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index 3bed6be..b473a4c 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -18,6 +18,8 @@
#include <linux/pm_runtime.h>
#include <linux/suspend.h>
#include <linux/kexec.h>
+#include <linux/of_device.h>
+#include <linux/acpi.h>
#include "pci.h"
struct pci_dynid {
@@ -1522,6 +1524,35 @@ static int pci_bus_num_vf(struct device *dev)
return pci_num_vf(to_pci_dev(dev));
}
+/**
+ * pci_dma_configure - Setup DMA configuration
+ * @dev: ptr to dev structure
+ *
+ * Function to update PCI devices's DMA configuration using the same
+ * info from the OF node or ACPI node of host bridge's parent (if any).
+ */
+static int pci_dma_configure(struct device *dev)
+{
+ struct device *bridge;
+ enum dev_dma_attr attr;
+ int ret = 0;
+
+ bridge = pci_get_host_bridge_device(to_pci_dev(dev));
+
+ if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
+ bridge->parent->of_node) {
+ ret = of_dma_configure(dev, bridge->parent->of_node);
+ } else if (has_acpi_companion(bridge)) {
+ attr = acpi_get_dma_attr(to_acpi_device_node(bridge->fwnode));
+ if (attr != DEV_DMA_NOT_SUPPORTED)
+ ret = acpi_dma_configure(dev, attr);
+ }
+
+ pci_put_host_bridge_device(bridge);
+
+ return ret;
+}
+
struct bus_type pci_bus_type = {
.name = "pci",
.match = pci_bus_match,
@@ -1534,6 +1565,7 @@ struct bus_type pci_bus_type = {
.drv_groups = pci_drv_groups,
.pm = PCI_PM_OPS_PTR,
.num_vf = pci_bus_num_vf,
+ .dma_configure = pci_dma_configure,
.force_dma = true,
};
EXPORT_SYMBOL(pci_bus_type);
diff --git a/include/linux/device.h b/include/linux/device.h
index b093405..1832d90 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -88,6 +88,8 @@ extern int __must_check bus_create_file(struct bus_type *,
* @resume: Called to bring a device on this bus out of sleep mode.
* @num_vf: Called to find out how many virtual functions a device on this
* bus supports.
+ * @dma_configure: Called to setup DMA configuration on a device on
+ this bus.
* @pm: Power management operations of this bus, callback the specific
* device driver's pm-ops.
* @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
@@ -130,6 +132,8 @@ struct bus_type {
int (*num_vf)(struct device *dev);
+ int (*dma_configure)(struct device *dev);
+
const struct dev_pm_ops *pm;
const struct iommu_ops *iommu_ops;
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index eb9eab4..c15986b 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -761,6 +761,7 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
+int dma_common_configure(struct device *dev);
#ifdef CONFIG_HAS_DMA
int dma_configure(struct device *dev);
void dma_deconfigure(struct device *dev);
--
1.9.1
On Wed, Mar 21, 2018 at 04:28:46PM +0000, Nipun Gupta wrote:
>
>
> > -----Original Message-----
> > From: Greg KH [mailto:[email protected]]
> > Sent: Wednesday, March 21, 2018 15:05
> > To: Nipun Gupta <[email protected]>
> > Cc: [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected]; [email protected]
> > foundation.org; [email protected]; linux-arm-
> > [email protected]; [email protected]; [email protected];
> > [email protected]; [email protected];
> > [email protected]; [email protected]; Bharat Bhushan
> > <[email protected]>; Leo Li <[email protected]>
> > Subject: Re: [PATCH v2 2/2] drivers: remove force dma flag from buses
> >
> > On Wed, Mar 21, 2018 at 12:25:23PM +0530, Nipun Gupta wrote:
> > > With each bus implementing its own DMA configuration callback,
> > > there is no need for bus to explicitly have force_dma in its
> > > global structure. This patch modifies of_dma_configure API to
> > > accept an input parameter which specifies if implicit DMA
> > > configuration is required even when it is not described by the
> > > firmware.
> >
> > Having to "remember" what that bool variable means on the end of the
> > function call is a royal pain over time, right?
> >
> > Why not just create a new function:
> > dma_common_configure_force(dma)
> > that always does this? Leave "dma_common_configure()" alone, and then
> > wrap the old code with these two helper functions that call the 'core'
> > code with the bool set properly?
> >
> > That way you do not have to "know" what that parameter is, the function
> > name just documents it automatically, so when you see it in the
> > bus-specific code, no need to go and have to hunt for anything. And if
> > you are reading the dma core code, it's obvious what is happening as the
> > functions are all right there.
>
> How about we do not pass any flag in 'dma_common_configure()', and inside this
> API we pass "true" to 'of_dma_configure()'? I am saying this because currently
> both the busses (platform and AMBA) which uses 'dma_common_configure()' passes
> "true" value. If we create additional 'dma_common_configure_force()', then
> 'dma_common_configure()' will not be used anytime and will become redundant.
>
> If someday new busses come and they needs to use similar functionality which
> 'dma_common_configure()' provides, but with passing "false" to 'of_dma_configure()',
> then what you suggests of having two separate such API's will be more reasonable
> and can be implemented?
If that makes things "simple", yes, sounds good.
greg k-h
On Wed, Mar 21, 2018 at 12:25:23PM +0530, Nipun Gupta wrote:
> With each bus implementing its own DMA configuration callback,
> there is no need for bus to explicitly have force_dma in its
> global structure. This patch modifies of_dma_configure API to
> accept an input parameter which specifies if implicit DMA
> configuration is required even when it is not described by the
> firmware.
Having to "remember" what that bool variable means on the end of the
function call is a royal pain over time, right?
Why not just create a new function:
dma_common_configure_force(dma)
that always does this? Leave "dma_common_configure()" alone, and then
wrap the old code with these two helper functions that call the 'core'
code with the bool set properly?
That way you do not have to "know" what that parameter is, the function
name just documents it automatically, so when you see it in the
bus-specific code, no need to go and have to hunt for anything. And if
you are reading the dma core code, it's obvious what is happening as the
functions are all right there.
thanks,
greg k-h
Hi Nipun,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v4.16-rc6 next-20180323]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Nipun-Gupta/dma-mapping-move-dma-configuration-to-bus-infrastructure/20180323-232307
config: i386-randconfig-x013-201811 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers/base/dma-mapping.c: In function 'dma_common_configure':
>> drivers/base/dma-mapping.c:344:9: error: too many arguments to function 'of_dma_configure'
ret = of_dma_configure(dev, dev->of_node, force_dma);
^~~~~~~~~~~~~~~~
In file included from drivers/base/dma-mapping.c:13:0:
include/linux/of_device.h:110:19: note: declared here
static inline int of_dma_configure(struct device *dev, struct device_node *np)
^~~~~~~~~~~~~~~~
--
drivers/pci/pci-driver.c: In function 'pci_dma_configure':
>> drivers/pci/pci-driver.c:1544:9: error: too many arguments to function 'of_dma_configure'
ret = of_dma_configure(dev, bridge->parent->of_node, true);
^~~~~~~~~~~~~~~~
In file included from drivers/pci/pci-driver.c:21:0:
include/linux/of_device.h:110:19: note: declared here
static inline int of_dma_configure(struct device *dev, struct device_node *np)
^~~~~~~~~~~~~~~~
vim +/of_dma_configure +344 drivers/base/dma-mapping.c
332
333 /*
334 * Common configuration to enable DMA API use for a device.
335 * A bus can use this function in its 'dma_configure' callback, if
336 * suitable for the bus.
337 */
338 int dma_common_configure(struct device *dev, bool force_dma)
339 {
340 enum dev_dma_attr attr;
341 int ret = 0;
342
343 if (dev->of_node) {
> 344 ret = of_dma_configure(dev, dev->of_node, force_dma);
345 } else if (has_acpi_companion(dev)) {
346 attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
347 if (attr != DEV_DMA_NOT_SUPPORTED)
348 ret = acpi_dma_configure(dev, attr);
349 }
350
351 return ret;
352 }
353
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Nipun,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v4.16-rc6 next-20180323]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Nipun-Gupta/dma-mapping-move-dma-configuration-to-bus-infrastructure/20180323-232307
config: i386-randconfig-x014-201811 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=i386
All errors (new ones prefixed by >>):
drivers//bcma/main.c: In function 'bcma_of_fill_device':
>> drivers//bcma/main.c:210:2: error: too many arguments to function 'of_dma_configure'
of_dma_configure(&core->dev, node, false);
^~~~~~~~~~~~~~~~
In file included from include/linux/of_platform.h:12:0,
from drivers//bcma/main.c:17:
include/linux/of_device.h:110:19: note: declared here
static inline int of_dma_configure(struct device *dev, struct device_node *np)
^~~~~~~~~~~~~~~~
vim +/of_dma_configure +210 drivers//bcma/main.c
198
199 static void bcma_of_fill_device(struct device *parent,
200 struct bcma_device *core)
201 {
202 struct device_node *node;
203
204 node = bcma_of_find_child_device(parent, core);
205 if (node)
206 core->dev.of_node = node;
207
208 core->irq = bcma_of_get_irq(parent, core, 0);
209
> 210 of_dma_configure(&core->dev, node, false);
211 }
212
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
> -----Original Message-----
> From: Christoph Hellwig [mailto:[email protected]]
> Sent: Thursday, March 22, 2018 13:46
> To: Nipun Gupta <[email protected]>
>=20
> > +static int amba_dma_configure(struct device *dev)
> > +{
> > + return dma_common_configure(dev);
> > +}
>=20
> So it turns out we only end with two callers of dma_common_configure
> after this series. Based ont hat I'm tempted with the suggestion
> from Robin to just have amba call platform_dma_configure, and move
> the code from dma_common_configure to platform_dma_configure.
okay, that would be fine, trivial query - will it be okay to include
'linux/platform_device.h' in the AMBA bus? I am reluctant for this change
because of including platform file.
Thanks,
Nipun
With each bus implementing its own DMA configuration callback,
there is no need for bus to explicitly have force_dma in its
global structure. This patch modifies of_dma_configure API to
accept an input parameter which specifies if implicit DMA
configuration is required even when it is not described by the
firmware.
Signed-off-by: Nipun Gupta <[email protected]>
---
Changes in v2:
- This is a new change suggested by Robin and Christoph
and is added to the series.
drivers/amba/bus.c | 3 +--
drivers/base/dma-mapping.c | 4 ++--
drivers/base/platform.c | 3 +--
drivers/bcma/main.c | 2 +-
drivers/dma/qcom/hidma_mgmt.c | 2 +-
drivers/gpu/host1x/bus.c | 5 ++---
drivers/of/device.c | 6 ++++--
drivers/of/of_reserved_mem.c | 2 +-
drivers/pci/pci-driver.c | 3 +--
include/linux/device.h | 4 ----
include/linux/dma-mapping.h | 2 +-
include/linux/of_device.h | 4 +++-
12 files changed, 18 insertions(+), 22 deletions(-)
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
index 2fa1e8b..1d58348 100644
--- a/drivers/amba/bus.c
+++ b/drivers/amba/bus.c
@@ -174,7 +174,7 @@ static int amba_pm_runtime_resume(struct device *dev)
static int amba_dma_configure(struct device *dev)
{
- return dma_common_configure(dev);
+ return dma_common_configure(dev, true);
}
static const struct dev_pm_ops amba_pm = {
@@ -202,7 +202,6 @@ struct bus_type amba_bustype = {
.uevent = amba_uevent,
.dma_configure = amba_dma_configure,
.pm = &amba_pm,
- .force_dma = true,
};
static int __init amba_init(void)
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index 48f9af0..03f8584 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -335,13 +335,13 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
* A bus can use this function in its 'dma_configure' callback, if
* suitable for the bus.
*/
-int dma_common_configure(struct device *dev)
+int dma_common_configure(struct device *dev, bool force_dma)
{
enum dev_dma_attr attr;
int ret = 0;
if (dev->of_node) {
- ret = of_dma_configure(dev, dev->of_node);
+ ret = of_dma_configure(dev, dev->of_node, force_dma);
} else if (has_acpi_companion(dev)) {
attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
if (attr != DEV_DMA_NOT_SUPPORTED)
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index d2d5891..154707c 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -1132,7 +1132,7 @@ int platform_pm_restore(struct device *dev)
static int platform_dma_configure(struct device *dev)
{
- return dma_common_configure(dev);
+ return dma_common_configure(dev, true);
}
static const struct dev_pm_ops platform_dev_pm_ops = {
@@ -1148,7 +1148,6 @@ struct bus_type platform_bus_type = {
.uevent = platform_uevent,
.dma_configure = platform_dma_configure,
.pm = &platform_dev_pm_ops,
- .force_dma = true,
};
EXPORT_SYMBOL_GPL(platform_bus_type);
diff --git a/drivers/bcma/main.c b/drivers/bcma/main.c
index e6986c7..fc1f4ac 100644
--- a/drivers/bcma/main.c
+++ b/drivers/bcma/main.c
@@ -207,7 +207,7 @@ static void bcma_of_fill_device(struct device *parent,
core->irq = bcma_of_get_irq(parent, core, 0);
- of_dma_configure(&core->dev, node);
+ of_dma_configure(&core->dev, node, false);
}
unsigned int bcma_core_irq(struct bcma_device *core, int num)
diff --git a/drivers/dma/qcom/hidma_mgmt.c b/drivers/dma/qcom/hidma_mgmt.c
index 000c7019..d64edeb 100644
--- a/drivers/dma/qcom/hidma_mgmt.c
+++ b/drivers/dma/qcom/hidma_mgmt.c
@@ -398,7 +398,7 @@ static int __init hidma_mgmt_of_populate_channels(struct device_node *np)
}
of_node_get(child);
new_pdev->dev.of_node = child;
- of_dma_configure(&new_pdev->dev, child);
+ of_dma_configure(&new_pdev->dev, child, true);
/*
* It is assumed that calling of_msi_configure is safe on
* platforms with or without MSI support.
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index fa9896d..211eb6b 100644
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -317,7 +317,7 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
static int host1x_dma_configure(struct device *dev)
{
if (dev->of_node)
- return of_dma_configure(dev, dev->of_node);
+ return of_dma_configure(dev, dev->of_node, true);
return 0;
}
@@ -336,7 +336,6 @@ struct bus_type host1x_bus_type = {
.match = host1x_device_match,
.dma_configure = host1x_dma_configure,
.pm = &host1x_device_pm_ops,
- .force_dma = true,
};
static void __host1x_device_del(struct host1x_device *device)
@@ -425,7 +424,7 @@ static int host1x_device_add(struct host1x *host1x,
device->dev.bus = &host1x_bus_type;
device->dev.parent = host1x->dev;
- of_dma_configure(&device->dev, host1x->dev->of_node);
+ of_dma_configure(&device->dev, host1x->dev->of_node, true);
err = host1x_device_parse_dt(device, driver);
if (err < 0) {
diff --git a/drivers/of/device.c b/drivers/of/device.c
index 064c818..33d8551 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -76,6 +76,8 @@ int of_device_add(struct platform_device *ofdev)
* of_dma_configure - Setup DMA configuration
* @dev: Device to apply DMA configuration
* @np: Pointer to OF node having DMA configuration
+ * @force_dma: Whether device is to be set up by of_dma_configure() even if
+ * DMA capability is not explicitly described by firmware.
*
* Try to get devices's DMA configuration from DT and update it
* accordingly.
@@ -84,7 +86,7 @@ int of_device_add(struct platform_device *ofdev)
* can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
* to fix up DMA configuration.
*/
-int of_dma_configure(struct device *dev, struct device_node *np)
+int of_dma_configure(struct device *dev, struct device_node *np, bool force_dma)
{
u64 dma_addr, paddr, size = 0;
int ret;
@@ -100,7 +102,7 @@ int of_dma_configure(struct device *dev, struct device_node *np)
* DMA configuration regardless of whether "dma-ranges" is
* correctly specified or not.
*/
- if (!dev->bus->force_dma)
+ if (!force_dma)
return ret == -ENODEV ? 0 : ret;
dma_addr = offset = 0;
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index 9a4f4246..895c83e 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -353,7 +353,7 @@ int of_reserved_mem_device_init_by_idx(struct device *dev,
/* ensure that dma_ops is set for virtual devices
* using reserved memory
*/
- of_dma_configure(dev, np);
+ of_dma_configure(dev, np, true);
dev_info(dev, "assigned reserved memory node %s\n", rmem->name);
} else {
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index b473a4c..b15637a 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -1541,7 +1541,7 @@ static int pci_dma_configure(struct device *dev)
if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
bridge->parent->of_node) {
- ret = of_dma_configure(dev, bridge->parent->of_node);
+ ret = of_dma_configure(dev, bridge->parent->of_node, true);
} else if (has_acpi_companion(bridge)) {
attr = acpi_get_dma_attr(to_acpi_device_node(bridge->fwnode));
if (attr != DEV_DMA_NOT_SUPPORTED)
@@ -1566,7 +1566,6 @@ struct bus_type pci_bus_type = {
.pm = PCI_PM_OPS_PTR,
.num_vf = pci_bus_num_vf,
.dma_configure = pci_dma_configure,
- .force_dma = true,
};
EXPORT_SYMBOL(pci_bus_type);
diff --git a/include/linux/device.h b/include/linux/device.h
index 1832d90..92c530e 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -98,8 +98,6 @@ extern int __must_check bus_create_file(struct bus_type *,
* @p: The private data of the driver core, only the driver core can
* touch this.
* @lock_key: Lock class key for use by the lock validator
- * @force_dma: Assume devices on this bus should be set up by dma_configure()
- * even if DMA capability is not explicitly described by firmware.
*
* A bus is a channel between the processor and one or more devices. For the
* purposes of the device model, all devices are connected via a bus, even if
@@ -140,8 +138,6 @@ struct bus_type {
struct subsys_private *p;
struct lock_class_key lock_key;
-
- bool force_dma;
};
extern int __must_check bus_register(struct bus_type *bus);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index c15986b..3dba3e6 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -761,7 +761,7 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
-int dma_common_configure(struct device *dev);
+int dma_common_configure(struct device *dev, bool force_dma);
#ifdef CONFIG_HAS_DMA
int dma_configure(struct device *dev);
void dma_deconfigure(struct device *dev);
diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index 8da5a1b..b0be3a5 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -55,7 +55,9 @@ static inline struct device_node *of_cpu_device_node_get(int cpu)
return of_node_get(cpu_dev->of_node);
}
-int of_dma_configure(struct device *dev, struct device_node *np);
+int of_dma_configure(struct device *dev,
+ struct device_node *np,
+ bool force_dma);
void of_dma_deconfigure(struct device *dev);
#else /* CONFIG_OF */
--
1.9.1
On Wed, Mar 21, 2018 at 12:25:22PM +0530, Nipun Gupta wrote:
> It's bus specific aspect to map a given device on the bus and
> relevant firmware description of its DMA configuration.
> So, this change introduces '/dma_configure/' as bus callback
> giving flexibility to busses for implementing its own dma
> configuration function.
>
> The change eases the addition of new busses w.r.t. adding the dma
> configuration functionality.
>
> This patch also updates the PCI, Platform, ACPI and host1x bus to
> use new introduced callbacks.
>
> Suggested-by: Christoph Hellwig <[email protected]>
> Signed-off-by: Nipun Gupta <[email protected]>
> ---
> - The patches are based on the comments on:
> https://patchwork.kernel.org/patch/10259087/
>
> Changes in v2:
> - Do not have dma_deconfigure callback
> - Have '/dma_common_configure/' API to provide a common DMA
> configuration which can be used by busses if it suits them.
> - Platform and ACPI bus to use '/dma_common_configure/' in
> '/dma_configure/' callback.
> - Updated commit message
> - Updated pci_dma_configure API with changes suggested by Robin
>
> drivers/amba/bus.c | 7 +++++++
> drivers/base/dma-mapping.c | 35 +++++++++++++++--------------------
> drivers/base/platform.c | 6 ++++++
> drivers/gpu/host1x/bus.c | 9 +++++++++
> drivers/pci/pci-driver.c | 32 ++++++++++++++++++++++++++++++++
> include/linux/device.h | 4 ++++
> include/linux/dma-mapping.h | 1 +
> 7 files changed, 74 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
> index 594c228..2fa1e8b 100644
> --- a/drivers/amba/bus.c
> +++ b/drivers/amba/bus.c
> @@ -20,6 +20,7 @@
> #include <linux/sizes.h>
> #include <linux/limits.h>
> #include <linux/clk/clk-conf.h>
> +#include <linux/dma-mapping.h>
>
> #include <asm/irq.h>
>
> @@ -171,6 +172,11 @@ static int amba_pm_runtime_resume(struct device *dev)
> }
> #endif /* CONFIG_PM */
>
> +static int amba_dma_configure(struct device *dev)
> +{
> + return dma_common_configure(dev);
> +}
> +
> static const struct dev_pm_ops amba_pm = {
> .suspend = pm_generic_suspend,
> .resume = pm_generic_resume,
> @@ -194,6 +200,7 @@ struct bus_type amba_bustype = {
> .dev_groups = amba_dev_groups,
> .match = amba_match,
> .uevent = amba_uevent,
> + .dma_configure = amba_dma_configure,
> .pm = &amba_pm,
> .force_dma = true,
> };
> diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
> index 3b11835..48f9af0 100644
> --- a/drivers/base/dma-mapping.c
> +++ b/drivers/base/dma-mapping.c
> @@ -331,38 +331,33 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
> #endif
>
> /*
> - * Common configuration to enable DMA API use for a device
> + * Common configuration to enable DMA API use for a device.
> + * A bus can use this function in its 'dma_configure' callback, if
> + * suitable for the bus.
> */
> -#include <linux/pci.h>
> -
> -int dma_configure(struct device *dev)
> +int dma_common_configure(struct device *dev)
> {
> - struct device *bridge = NULL, *dma_dev = dev;
> enum dev_dma_attr attr;
> int ret = 0;
>
> - if (dev_is_pci(dev)) {
> - bridge = pci_get_host_bridge_device(to_pci_dev(dev));
> - dma_dev = bridge;
> - if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
> - dma_dev->parent->of_node)
> - dma_dev = dma_dev->parent;
> - }
> -
> - if (dma_dev->of_node) {
> - ret = of_dma_configure(dev, dma_dev->of_node);
> - } else if (has_acpi_companion(dma_dev)) {
> - attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode));
> + if (dev->of_node) {
> + ret = of_dma_configure(dev, dev->of_node);
> + } else if (has_acpi_companion(dev)) {
> + attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
> if (attr != DEV_DMA_NOT_SUPPORTED)
> ret = acpi_dma_configure(dev, attr);
> }
>
> - if (bridge)
> - pci_put_host_bridge_device(bridge);
> -
> return ret;
> }
>
> +int dma_configure(struct device *dev)
> +{
> + if (dev->bus->dma_configure)
> + return dev->bus->dma_configure(dev);
> +
> + return 0;
> +}
> void dma_deconfigure(struct device *dev)
Empty line after this new function? Sorry, couldn't help it :)
> {
> of_dma_deconfigure(dev);
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index f1bf7b3..d2d5891 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -1130,6 +1130,11 @@ int platform_pm_restore(struct device *dev)
>
> #endif /* CONFIG_HIBERNATE_CALLBACKS */
>
> +static int platform_dma_configure(struct device *dev)
> +{
> + return dma_common_configure(dev);
> +}
> +
> static const struct dev_pm_ops platform_dev_pm_ops = {
> .runtime_suspend = pm_generic_runtime_suspend,
> .runtime_resume = pm_generic_runtime_resume,
> @@ -1141,6 +1146,7 @@ struct bus_type platform_bus_type = {
> .dev_groups = platform_dev_groups,
> .match = platform_match,
> .uevent = platform_uevent,
> + .dma_configure = platform_dma_configure,
> .pm = &platform_dev_pm_ops,
> .force_dma = true,
> };
> diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
> index 88a3558..fa9896d 100644
> --- a/drivers/gpu/host1x/bus.c
> +++ b/drivers/gpu/host1x/bus.c
> @@ -314,6 +314,14 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
> return strcmp(dev_name(dev), drv->name) == 0;
> }
>
> +static int host1x_dma_configure(struct device *dev)
> +{
> + if (dev->of_node)
> + return of_dma_configure(dev, dev->of_node);
> +
> + return 0;
> +}
> +
> static const struct dev_pm_ops host1x_device_pm_ops = {
> .suspend = pm_generic_suspend,
> .resume = pm_generic_resume,
> @@ -326,6 +334,7 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
> struct bus_type host1x_bus_type = {
> .name = "host1x",
> .match = host1x_device_match,
> + .dma_configure = host1x_dma_configure,
> .pm = &host1x_device_pm_ops,
> .force_dma = true,
> };
> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
> index 3bed6be..b473a4c 100644
> --- a/drivers/pci/pci-driver.c
> +++ b/drivers/pci/pci-driver.c
> @@ -18,6 +18,8 @@
> #include <linux/pm_runtime.h>
> #include <linux/suspend.h>
> #include <linux/kexec.h>
> +#include <linux/of_device.h>
> +#include <linux/acpi.h>
> #include "pci.h"
>
> struct pci_dynid {
> @@ -1522,6 +1524,35 @@ static int pci_bus_num_vf(struct device *dev)
> return pci_num_vf(to_pci_dev(dev));
> }
>
> +/**
> + * pci_dma_configure - Setup DMA configuration
> + * @dev: ptr to dev structure
> + *
> + * Function to update PCI devices's DMA configuration using the same
> + * info from the OF node or ACPI node of host bridge's parent (if any).
> + */
> +static int pci_dma_configure(struct device *dev)
> +{
> + struct device *bridge;
> + enum dev_dma_attr attr;
> + int ret = 0;
> +
> + bridge = pci_get_host_bridge_device(to_pci_dev(dev));
> +
> + if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
> + bridge->parent->of_node) {
> + ret = of_dma_configure(dev, bridge->parent->of_node);
> + } else if (has_acpi_companion(bridge)) {
> + attr = acpi_get_dma_attr(to_acpi_device_node(bridge->fwnode));
> + if (attr != DEV_DMA_NOT_SUPPORTED)
> + ret = acpi_dma_configure(dev, attr);
> + }
> +
> + pci_put_host_bridge_device(bridge);
> +
> + return ret;
> +}
> +
> struct bus_type pci_bus_type = {
> .name = "pci",
> .match = pci_bus_match,
> @@ -1534,6 +1565,7 @@ struct bus_type pci_bus_type = {
> .drv_groups = pci_drv_groups,
> .pm = PCI_PM_OPS_PTR,
> .num_vf = pci_bus_num_vf,
> + .dma_configure = pci_dma_configure,
> .force_dma = true,
> };
> EXPORT_SYMBOL(pci_bus_type);
> diff --git a/include/linux/device.h b/include/linux/device.h
> index b093405..1832d90 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -88,6 +88,8 @@ extern int __must_check bus_create_file(struct bus_type *,
> * @resume: Called to bring a device on this bus out of sleep mode.
> * @num_vf: Called to find out how many virtual functions a device on this
> * bus supports.
> + * @dma_configure: Called to setup DMA configuration on a device on
> + this bus.
> * @pm: Power management operations of this bus, callback the specific
> * device driver's pm-ops.
> * @iommu_ops: IOMMU specific operations for this bus, used to attach IOMMU
> @@ -130,6 +132,8 @@ struct bus_type {
>
> int (*num_vf)(struct device *dev);
>
> + int (*dma_configure)(struct device *dev);
> +
> const struct dev_pm_ops *pm;
>
> const struct iommu_ops *iommu_ops;
> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
> index eb9eab4..c15986b 100644
> --- a/include/linux/dma-mapping.h
> +++ b/include/linux/dma-mapping.h
> @@ -761,6 +761,7 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
> }
> #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
>
> +int dma_common_configure(struct device *dev);
> #ifdef CONFIG_HAS_DMA
Blank line after the new function declaration?
Other than those very minor things, nice job, this looks good:
Reviewed-by: Greg Kroah-Hartman <[email protected]>
> +static int amba_dma_configure(struct device *dev)
> +{
> + return dma_common_configure(dev);
> +}
So it turns out we only end with two callers of dma_common_configure
after this series. Based ont hat I'm tempted with the suggestion
from Robin to just have amba call platform_dma_configure, and move
the code from dma_common_configure to platform_dma_configure.
> +int dma_configure(struct device *dev)
> +{
> + if (dev->bus->dma_configure)
> + return dev->bus->dma_configure(dev);
> +
> + return 0;
> +}
> void dma_deconfigure(struct device *dev)
As grep pointed out this wants a blank line after the function, and while
in nitpicking mode I'd suggest to remove the blank line above the return
statement while at it.
> diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
> index 88a3558..fa9896d 100644
> --- a/drivers/gpu/host1x/bus.c
> +++ b/drivers/gpu/host1x/bus.c
> @@ -314,6 +314,14 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
> return strcmp(dev_name(dev), drv->name) == 0;
> }
>
> +static int host1x_dma_configure(struct device *dev)
> +{
> + if (dev->of_node)
> + return of_dma_configure(dev, dev->of_node);
> +
> + return 0;
Same here.
> + */
> +static int pci_dma_configure(struct device *dev)
> +{
> + struct device *bridge;
> + enum dev_dma_attr attr;
> + int ret = 0;
> +
> + bridge = pci_get_host_bridge_device(to_pci_dev(dev));
> +
> + if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
> + bridge->parent->of_node) {
> + ret = of_dma_configure(dev, bridge->parent->of_node);
> + } else if (has_acpi_companion(bridge)) {
> + attr = acpi_get_dma_attr(to_acpi_device_node(bridge->fwnode));
> + if (attr != DEV_DMA_NOT_SUPPORTED)
> + ret = acpi_dma_configure(dev, attr);
> + }
The attr declaration can be moved into the inner scope here.
> + pci_put_host_bridge_device(bridge);
> +
> + return ret;
Drop the blank line after the return, please.
> --- a/drivers/dma/qcom/hidma_mgmt.c
> +++ b/drivers/dma/qcom/hidma_mgmt.c
> @@ -398,7 +398,7 @@ static int __init hidma_mgmt_of_populate_channels(struct device_node *np)
> }
> of_node_get(child);
> new_pdev->dev.of_node = child;
> - of_dma_configure(&new_pdev->dev, child);
> + of_dma_configure(&new_pdev->dev, child, true);
> /*
> * It is assumed that calling of_msi_configure is safe on
> * platforms with or without MSI support.
Where did we mark this bus as force_dma before?
> diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
> index 9a4f4246..895c83e 100644
> --- a/drivers/of/of_reserved_mem.c
> +++ b/drivers/of/of_reserved_mem.c
> @@ -353,7 +353,7 @@ int of_reserved_mem_device_init_by_idx(struct device *dev,
> /* ensure that dma_ops is set for virtual devices
> * using reserved memory
> */
> - of_dma_configure(dev, np);
> + of_dma_configure(dev, np, true);
Did all the callers of this one really force dma? I have a hard time
untangling the call stacks unfortunately.
> -----Original Message-----
> From: Nipun Gupta
> Sent: Wednesday, March 21, 2018 12:25 PM
> To: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected]; [email protected]; linux-
> [email protected]; [email protected]; linux-
> [email protected]; [email protected]; linux-
> [email protected]; [email protected]; dri-
> [email protected]; [email protected];
> [email protected]; [email protected]; Bharat Bhushan
> <[email protected]>; Leo Li <[email protected]>; Nipun Gupta
> <[email protected]>
> Subject: [PATCH v2 1/2] dma-mapping: move dma configuration to bus
> infrastructure
>=20
> It's bus specific aspect to map a given device on the bus and relevant fi=
rmware
> description of its DMA configuration.
> So, this change introduces '/dma_configure/' as bus callback giving flexi=
bility to
> busses for implementing its own dma configuration function.
>=20
> The change eases the addition of new busses w.r.t. adding the dma
> configuration functionality.
>=20
> This patch also updates the PCI, Platform, ACPI and host1x bus to use new
> introduced callbacks.
>=20
> Suggested-by: Christoph Hellwig <[email protected]>
> Signed-off-by: Nipun Gupta <[email protected]>
> ---
> - The patches are based on the comments on:
> https://patchwork.kernel.org/patch/10259087/
>=20
> Changes in v2:
> - Do not have dma_deconfigure callback
> - Have '/dma_common_configure/' API to provide a common DMA
> configuration which can be used by busses if it suits them.
> - Platform and ACPI bus to use '/dma_common_configure/' in
> '/dma_configure/' callback.
> - Updated commit message
> - Updated pci_dma_configure API with changes suggested by Robin
>=20
> drivers/amba/bus.c | 7 +++++++
> drivers/base/dma-mapping.c | 35 +++++++++++++++--------------------
> drivers/base/platform.c | 6 ++++++
> drivers/gpu/host1x/bus.c | 9 +++++++++
> drivers/pci/pci-driver.c | 32 ++++++++++++++++++++++++++++++++
> include/linux/device.h | 4 ++++
> include/linux/dma-mapping.h | 1 +
> 7 files changed, 74 insertions(+), 20 deletions(-)
>=20
> diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 594c228..2fa1e=
8b
> 100644
> --- a/drivers/amba/bus.c
> +++ b/drivers/amba/bus.c
> @@ -20,6 +20,7 @@
> #include <linux/sizes.h>
> #include <linux/limits.h>
> #include <linux/clk/clk-conf.h>
> +#include <linux/dma-mapping.h>
>=20
> #include <asm/irq.h>
>=20
> @@ -171,6 +172,11 @@ static int amba_pm_runtime_resume(struct device
> *dev) } #endif /* CONFIG_PM */
>=20
> +static int amba_dma_configure(struct device *dev) {
> + return dma_common_configure(dev);
> +}
> +
> static const struct dev_pm_ops amba_pm =3D {
> .suspend =3D pm_generic_suspend,
> .resume =3D pm_generic_resume,
> @@ -194,6 +200,7 @@ struct bus_type amba_bustype =3D {
> .dev_groups =3D amba_dev_groups,
> .match =3D amba_match,
> .uevent =3D amba_uevent,
> + .dma_configure =3D amba_dma_configure,
> .pm =3D &amba_pm,
> .force_dma =3D true,
> };
> diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c inde=
x
> 3b11835..48f9af0 100644
> --- a/drivers/base/dma-mapping.c
> +++ b/drivers/base/dma-mapping.c
> @@ -331,38 +331,33 @@ void dma_common_free_remap(void *cpu_addr,
> size_t size, unsigned long vm_flags) #endif
>=20
> /*
> - * Common configuration to enable DMA API use for a device
> + * Common configuration to enable DMA API use for a device.
> + * A bus can use this function in its 'dma_configure' callback, if
> + * suitable for the bus.
> */
> -#include <linux/pci.h>
> -
> -int dma_configure(struct device *dev)
> +int dma_common_configure(struct device *dev)
> {
> - struct device *bridge =3D NULL, *dma_dev =3D dev;
> enum dev_dma_attr attr;
> int ret =3D 0;
>=20
> - if (dev_is_pci(dev)) {
> - bridge =3D pci_get_host_bridge_device(to_pci_dev(dev));
> - dma_dev =3D bridge;
> - if (IS_ENABLED(CONFIG_OF) && dma_dev->parent &&
> - dma_dev->parent->of_node)
> - dma_dev =3D dma_dev->parent;
> - }
> -
> - if (dma_dev->of_node) {
> - ret =3D of_dma_configure(dev, dma_dev->of_node);
> - } else if (has_acpi_companion(dma_dev)) {
> - attr =3D acpi_get_dma_attr(to_acpi_device_node(dma_dev-
> >fwnode));
> + if (dev->of_node) {
> + ret =3D of_dma_configure(dev, dev->of_node);
> + } else if (has_acpi_companion(dev)) {
> + attr =3D acpi_get_dma_attr(to_acpi_device_node(dev->fwnode));
> if (attr !=3D DEV_DMA_NOT_SUPPORTED)
> ret =3D acpi_dma_configure(dev, attr);
> }
>=20
> - if (bridge)
> - pci_put_host_bridge_device(bridge);
> -
> return ret;
> }
>=20
> +int dma_configure(struct device *dev)
> +{
> + if (dev->bus->dma_configure)
> + return dev->bus->dma_configure(dev);
What if dma_common_configure() is called in case "bus->dma_configure" is no=
t defined?
Thanks
-Bharat
> +
> + return 0;
> +}
> void dma_deconfigure(struct device *dev) {
> of_dma_deconfigure(dev);
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c index
> f1bf7b3..d2d5891 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -1130,6 +1130,11 @@ int platform_pm_restore(struct device *dev)
>=20
> #endif /* CONFIG_HIBERNATE_CALLBACKS */
>=20
> +static int platform_dma_configure(struct device *dev) {
> + return dma_common_configure(dev);
> +}
> +
> static const struct dev_pm_ops platform_dev_pm_ops =3D {
> .runtime_suspend =3D pm_generic_runtime_suspend,
> .runtime_resume =3D pm_generic_runtime_resume, @@ -1141,6 +1146,7
> @@ struct bus_type platform_bus_type =3D {
> .dev_groups =3D platform_dev_groups,
> .match =3D platform_match,
> .uevent =3D platform_uevent,
> + .dma_configure =3D platform_dma_configure,
> .pm =3D &platform_dev_pm_ops,
> .force_dma =3D true,
> };
> diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c index
> 88a3558..fa9896d 100644
> --- a/drivers/gpu/host1x/bus.c
> +++ b/drivers/gpu/host1x/bus.c
> @@ -314,6 +314,14 @@ static int host1x_device_match(struct device *dev,
> struct device_driver *drv)
> return strcmp(dev_name(dev), drv->name) =3D=3D 0; }
>=20
> +static int host1x_dma_configure(struct device *dev) {
> + if (dev->of_node)
> + return of_dma_configure(dev, dev->of_node);
> +
> + return 0;
> +}
> +
> static const struct dev_pm_ops host1x_device_pm_ops =3D {
> .suspend =3D pm_generic_suspend,
> .resume =3D pm_generic_resume,
> @@ -326,6 +334,7 @@ static int host1x_device_match(struct device *dev,
> struct device_driver *drv) struct bus_type host1x_bus_type =3D {
> .name =3D "host1x",
> .match =3D host1x_device_match,
> + .dma_configure =3D host1x_dma_configure,
> .pm =3D &host1x_device_pm_ops,
> .force_dma =3D true,
> };
> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index
> 3bed6be..b473a4c 100644
> --- a/drivers/pci/pci-driver.c
> +++ b/drivers/pci/pci-driver.c
> @@ -18,6 +18,8 @@
> #include <linux/pm_runtime.h>
> #include <linux/suspend.h>
> #include <linux/kexec.h>
> +#include <linux/of_device.h>
> +#include <linux/acpi.h>
> #include "pci.h"
>=20
> struct pci_dynid {
> @@ -1522,6 +1524,35 @@ static int pci_bus_num_vf(struct device *dev)
> return pci_num_vf(to_pci_dev(dev));
> }
>=20
> +/**
> + * pci_dma_configure - Setup DMA configuration
> + * @dev: ptr to dev structure
> + *
> + * Function to update PCI devices's DMA configuration using the same
> + * info from the OF node or ACPI node of host bridge's parent (if any).
> + */
> +static int pci_dma_configure(struct device *dev) {
> + struct device *bridge;
> + enum dev_dma_attr attr;
> + int ret =3D 0;
> +
> + bridge =3D pci_get_host_bridge_device(to_pci_dev(dev));
> +
> + if (IS_ENABLED(CONFIG_OF) && bridge->parent &&
> + bridge->parent->of_node) {
> + ret =3D of_dma_configure(dev, bridge->parent->of_node);
> + } else if (has_acpi_companion(bridge)) {
> + attr =3D acpi_get_dma_attr(to_acpi_device_node(bridge-
> >fwnode));
> + if (attr !=3D DEV_DMA_NOT_SUPPORTED)
> + ret =3D acpi_dma_configure(dev, attr);
> + }
> +
> + pci_put_host_bridge_device(bridge);
> +
> + return ret;
> +}
> +
> struct bus_type pci_bus_type =3D {
> .name =3D "pci",
> .match =3D pci_bus_match,
> @@ -1534,6 +1565,7 @@ struct bus_type pci_bus_type =3D {
> .drv_groups =3D pci_drv_groups,
> .pm =3D PCI_PM_OPS_PTR,
> .num_vf =3D pci_bus_num_vf,
> + .dma_configure =3D pci_dma_configure,
> .force_dma =3D true,
> };
> EXPORT_SYMBOL(pci_bus_type);
> diff --git a/include/linux/device.h b/include/linux/device.h index
> b093405..1832d90 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -88,6 +88,8 @@ extern int __must_check bus_create_file(struct bus_type
> *,
> * @resume: Called to bring a device on this bus out of sleep mode.
> * @num_vf: Called to find out how many virtual functions a device on th=
is
> * bus supports.
> + * @dma_configure: Called to setup DMA configuration on a device on
> + this bus.
> * @pm: Power management operations of this bus, callback the
> specific
> * device driver's pm-ops.
> * @iommu_ops: IOMMU specific operations for this bus, used to attach
> IOMMU @@ -130,6 +132,8 @@ struct bus_type {
>=20
> int (*num_vf)(struct device *dev);
>=20
> + int (*dma_configure)(struct device *dev);
> +
> const struct dev_pm_ops *pm;
>=20
> const struct iommu_ops *iommu_ops;
> diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h in=
dex
> eb9eab4..c15986b 100644
> --- a/include/linux/dma-mapping.h
> +++ b/include/linux/dma-mapping.h
> @@ -761,6 +761,7 @@ void *dma_mark_declared_memory_occupied(struct
> device *dev, } #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
>=20
> +int dma_common_configure(struct device *dev);
> #ifdef CONFIG_HAS_DMA
> int dma_configure(struct device *dev);
> void dma_deconfigure(struct device *dev);
> --
> 1.9.1
> -----Original Message-----
> From: Christoph Hellwig [mailto:[email protected]]
> Sent: Thursday, March 22, 2018 13:49
> To: Nipun Gupta <[email protected]>
>=20
> > --- a/drivers/dma/qcom/hidma_mgmt.c
> > +++ b/drivers/dma/qcom/hidma_mgmt.c
> > @@ -398,7 +398,7 @@ static int __init
> hidma_mgmt_of_populate_channels(struct device_node *np)
> > }
> > of_node_get(child);
> > new_pdev->dev.of_node =3D child;
> > - of_dma_configure(&new_pdev->dev, child);
> > + of_dma_configure(&new_pdev->dev, child, true);
> > /*
> > * It is assumed that calling of_msi_configure is safe on
> > * platforms with or without MSI support.
>=20
> Where did we mark this bus as force_dma before?
I thought these devices to be on the platform bus as the device is of type
'struct platform_device', though I am not sure then why 'of_dma_configure()=
'
is called here. Is this not on platform bus?
>=20
> > diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.=
c
> > index 9a4f4246..895c83e 100644
> > --- a/drivers/of/of_reserved_mem.c
> > +++ b/drivers/of/of_reserved_mem.c
> > @@ -353,7 +353,7 @@ int of_reserved_mem_device_init_by_idx(struct devic=
e
> *dev,
> > /* ensure that dma_ops is set for virtual devices
> > * using reserved memory
> > */
> > - of_dma_configure(dev, np);
> > + of_dma_configure(dev, np, true);
>=20
> Did all the callers of this one really force dma? I have a hard time
> untangling the call stacks unfortunately.
I see this API being called indirectly from NXP DPAA device driver which
is for platform bus devices. So I marked 'true' out here. There are more pl=
aces
from where it is being called.
Thanks,
Nipun
> -----Original Message-----
> From: Greg KH [mailto:[email protected]]
> Sent: Wednesday, March 21, 2018 15:00
<snip>
> > +int dma_configure(struct device *dev)
> > +{
> > + if (dev->bus->dma_configure)
> > + return dev->bus->dma_configure(dev);
> > +
> > + return 0;
> > +}
> > void dma_deconfigure(struct device *dev)
>=20
> Empty line after this new function? Sorry, couldn't help it :)
>=20
> > {
> > of_dma_deconfigure(dev);
> > diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> > index f1bf7b3..d2d5891 100644
> > --- a/drivers/base/platform.c
> > +++ b/drivers/base/platform.c
> > @@ -1130,6 +1130,11 @@ int platform_pm_restore(struct device *dev)
> >
> > #endif /* CONFIG_HIBERNATE_CALLBACKS */
> >
<snip>
> > +
> > const struct dev_pm_ops *pm;
> >
> > const struct iommu_ops *iommu_ops;
> > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
> > index eb9eab4..c15986b 100644
> > --- a/include/linux/dma-mapping.h
> > +++ b/include/linux/dma-mapping.h
> > @@ -761,6 +761,7 @@ void *dma_mark_declared_memory_occupied(struct
> device *dev,
> > }
> > #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
> >
> > +int dma_common_configure(struct device *dev);
> > #ifdef CONFIG_HAS_DMA
>=20
> Blank line after the new function declaration?
>=20
> Other than those very minor things, nice job, this looks good:
>=20
> Reviewed-by: Greg Kroah-Hartman <[email protected]>
Thank you for the review :). I will fix your comments in next version.
Regards,
Nipun
> -----Original Message-----
> From: Bharat Bhushan
> Sent: Wednesday, March 21, 2018 12:49
> >
> > +int dma_configure(struct device *dev)
> > +{
> > + if (dev->bus->dma_configure)
> > + return dev->bus->dma_configure(dev);
>=20
> What if dma_common_configure() is called in case "bus->dma_configure" is
> not defined?
>=20
> Thanks
> -Bharat
I think it is cleaner for bus to call '/dma_common_configure/' rather
than this been called implicitly, but Robin/Christoph can comment
better on this.
Thanks,
Nipun
> > +int dma_configure(struct device *dev)
> > +{
> > + if (dev->bus->dma_configure)
> > + return dev->bus->dma_configure(dev);
>
> What if dma_common_configure() is called in case "bus->dma_configure" is not defined?
Then we'd still have a dependency of common code on OF and ACPI.
On the other hand we'd get free OF and ACPI dma ranges parsing for
everyone, which might be handy. And which would really help mitigating
the risk that we missed some bus that gets dma configuration from OF,
so maybe it actually is a good idea. I'd just rename it to
dma_default_configure or similar in that case.
Hi Nipun,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v4.16-rc6]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Nipun-Gupta/dma-mapping-move-dma-configuration-to-bus-infrastructure/20180323-232307
config: score-spct6600_defconfig (attached as .config)
compiler: score-elf-gcc (GCC) 4.9.4
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=score
All errors (new ones prefixed by >>):
init/main.o: In function `try_to_run_init_process':
main.c:(.text+0x40): relocation truncated to fit: R_SCORE_24 against `run_init_process'
main.c:(.text+0x78): relocation truncated to fit: R_SCORE_24 against `.L36'
init/main.o: In function `.L132':
main.c:(.text+0x190): relocation truncated to fit: R_SCORE_24 against `.L129'
main.c:(.text+0x200): relocation truncated to fit: R_SCORE_24 against `.L132'
init/main.o: In function `loglevel':
main.c:(.init.text+0xa4): relocation truncated to fit: R_SCORE_24 against `get_option'
init/main.o: In function `.L15':
main.c:(.init.text+0x110): relocation truncated to fit: R_SCORE_24 against `strcmp'
main.c:(.init.text+0x124): relocation truncated to fit: R_SCORE_24 against `parameq'
main.c:(.init.text+0x14c): relocation truncated to fit: R_SCORE_24 against `printk'
init/main.o: In function `.L31':
main.c:(.init.text+0x160): relocation truncated to fit: R_SCORE_24 against `strcmp'
init/main.o: In function `.L21':
main.c:(.init.text+0x170): relocation truncated to fit: R_SCORE_24 against `.L15'
init/main.o: In function `initcall_blacklist':
main.c:(.init.text+0x198): additional relocation overflows omitted from the output
drivers/base/platform.o: In function `platform_dma_configure':
>> platform.c:(.text.platform_dma_configure+0x0): undefined reference to `dma_common_configure'
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation
> -----Original Message-----
> From: Greg KH [mailto:[email protected]]
> Sent: Wednesday, March 21, 2018 15:05
> To: Nipun Gupta <[email protected]>
> Cc: [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]; [email protected]; [email protected];
> [email protected]; [email protected]; [email protected]
> foundation.org; [email protected]; linux-arm-
> [email protected]; [email protected]; [email protected]=
;
> [email protected]; [email protected];
> [email protected]; [email protected]; Bharat Bhushan
> <[email protected]>; Leo Li <[email protected]>
> Subject: Re: [PATCH v2 2/2] drivers: remove force dma flag from buses
>=20
> On Wed, Mar 21, 2018 at 12:25:23PM +0530, Nipun Gupta wrote:
> > With each bus implementing its own DMA configuration callback,
> > there is no need for bus to explicitly have force_dma in its
> > global structure. This patch modifies of_dma_configure API to
> > accept an input parameter which specifies if implicit DMA
> > configuration is required even when it is not described by the
> > firmware.
>=20
> Having to "remember" what that bool variable means on the end of the
> function call is a royal pain over time, right?
>=20
> Why not just create a new function:
> dma_common_configure_force(dma)
> that always does this? Leave "dma_common_configure()" alone, and then
> wrap the old code with these two helper functions that call the 'core'
> code with the bool set properly?
>=20
> That way you do not have to "know" what that parameter is, the function
> name just documents it automatically, so when you see it in the
> bus-specific code, no need to go and have to hunt for anything. And if
> you are reading the dma core code, it's obvious what is happening as the
> functions are all right there.
How about we do not pass any flag in 'dma_common_configure()', and inside t=
his
API we pass "true" to 'of_dma_configure()'? I am saying this because curren=
tly
both the busses (platform and AMBA) which uses 'dma_common_configure()' pas=
ses
"true" value. If we create additional 'dma_common_configure_force()', then
'dma_common_configure()' will not be used anytime and will become redundant=
.
If someday new busses come and they needs to use similar functionality whic=
h
'dma_common_configure()' provides, but with passing "false" to 'of_dma_conf=
igure()',
then what you suggests of having two separate such API's will be more reaso=
nable
and can be implemented?
Thanks,
Nipun
>=20
> thanks,
>=20
> greg k-h