[PATCH V11 06/11] of/acpi: Configure dma operations at probe time for platform/amba/pci bus devices

From: Sricharan R
Date: Mon Apr 10 2017 - 07:22:35 EST


Configuring DMA ops at probe time will allow deferring device probe when
the IOMMU isn't available yet. The dma_configure for the device is
now called from the generic device_attach callback just before the
bus/driver probe is called. This way, configuring the DMA ops for the
device would be called at the same place for all bus_types, hence the
deferred probing mechanism should work for all buses as well.

pci_bus_add_devices (platform/amba)(_device_create/driver_register)
| |
pci_bus_add_device (device_add/driver_register)
| |
device_attach device_initial_probe
| |
__device_attach_driver __device_attach_driver
|
driver_probe_device
|
really_probe
|
dma_configure

Similarly on the device/driver_unregister path __device_release_driver is
called which inturn calls dma_deconfigure.

This patch changes the dma ops configuration to probe time for
both OF and ACPI based platform/amba/pci bus devices.

Tested-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Tested-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> (drivers/pci part)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
---
drivers/acpi/glue.c | 5 -----
drivers/base/dd.c | 9 +++++++++
drivers/base/dma-mapping.c | 40 ++++++++++++++++++++++++++++++++++++++++
drivers/of/platform.c | 5 +----
drivers/pci/probe.c | 28 ----------------------------
include/linux/dma-mapping.h | 12 ++++++++++++
6 files changed, 62 insertions(+), 37 deletions(-)

diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index fb19e1c..c05f241 100644
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c
@@ -176,7 +176,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
struct list_head *physnode_list;
unsigned int node_id;
int retval = -EINVAL;
- enum dev_dma_attr attr;

if (has_acpi_companion(dev)) {
if (acpi_dev) {
@@ -233,10 +232,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
if (!has_acpi_companion(dev))
ACPI_COMPANION_SET(dev, acpi_dev);

- attr = acpi_get_dma_attr(acpi_dev);
- if (attr != DEV_DMA_NOT_SUPPORTED)
- acpi_dma_configure(dev, attr);
-
acpi_physnode_link_name(physical_node_name, node_id);
retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
physical_node_name);
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index a1fbf55..4882f06 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -19,6 +19,7 @@

#include <linux/device.h>
#include <linux/delay.h>
+#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/wait.h>
@@ -356,6 +357,10 @@ static int really_probe(struct device *dev, struct device_driver *drv)
if (ret)
goto pinctrl_bind_failed;

+ ret = dma_configure(dev);
+ if (ret)
+ goto dma_failed;
+
if (driver_sysfs_add(dev)) {
printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
__func__, dev_name(dev));
@@ -417,6 +422,8 @@ static int really_probe(struct device *dev, struct device_driver *drv)
goto done;

probe_failed:
+ dma_deconfigure(dev);
+dma_failed:
if (dev->bus)
blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
@@ -826,6 +833,8 @@ static void __device_release_driver(struct device *dev, struct device *parent)
drv->remove(dev);

device_links_driver_cleanup(dev);
+ dma_deconfigure(dev);
+
devres_release_all(dev);
dev->driver = NULL;
dev_set_drvdata(dev, NULL);
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index efd71cf..449b948 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -7,9 +7,11 @@
* This file is released under the GPLv2.
*/

+#include <linux/acpi.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gfp.h>
+#include <linux/of_device.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

@@ -341,3 +343,41 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
vunmap(cpu_addr);
}
#endif
+
+/*
+ * Common configuration to enable DMA API use for a device
+ */
+#include <linux/pci.h>
+
+int dma_configure(struct device *dev)
+{
+ struct device *bridge = NULL, *dma_dev = dev;
+ enum dev_dma_attr attr;
+
+ 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) {
+ 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 (attr != DEV_DMA_NOT_SUPPORTED)
+ acpi_dma_configure(dev, attr);
+ }
+
+ if (bridge)
+ pci_put_host_bridge_device(bridge);
+
+ return 0;
+}
+
+void dma_deconfigure(struct device *dev)
+{
+ of_dma_deconfigure(dev);
+ acpi_dma_deconfigure(dev);
+}
diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 5344db5..2aa4ebb 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -22,6 +22,7 @@
#include <linux/slab.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
+#include <linux/of_iommu.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
@@ -186,11 +187,9 @@ static struct platform_device *of_platform_device_create_pdata(

dev->dev.bus = &platform_bus_type;
dev->dev.platform_data = platform_data;
- of_dma_configure(&dev->dev, dev->dev.of_node);
of_msi_configure(&dev->dev, dev->dev.of_node);

if (of_device_add(dev) != 0) {
- of_dma_deconfigure(&dev->dev);
platform_device_put(dev);
goto err_clear_flag;
}
@@ -248,7 +247,6 @@ static struct amba_device *of_amba_device_create(struct device_node *node,
dev_set_name(&dev->dev, "%s", bus_id);
else
of_device_make_bus_id(&dev->dev);
- of_dma_configure(&dev->dev, dev->dev.of_node);

/* Allow the HW Peripheral ID to be overridden */
prop = of_get_property(node, "arm,primecell-periphid", NULL);
@@ -542,7 +540,6 @@ static int of_platform_device_destroy(struct device *dev, void *data)
amba_device_unregister(to_amba_device(dev));
#endif

- of_dma_deconfigure(dev);
of_node_clear_flag(dev->of_node, OF_POPULATED);
of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
return 0;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index dfc9a27..5a8dd43 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1893,33 +1893,6 @@ static void pci_set_msi_domain(struct pci_dev *dev)
dev_set_msi_domain(&dev->dev, d);
}

-/**
- * pci_dma_configure - Setup DMA configuration
- * @dev: ptr to pci_dev struct of the PCI device
- *
- * 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 void pci_dma_configure(struct pci_dev *dev)
-{
- struct device *bridge = pci_get_host_bridge_device(dev);
-
- if (IS_ENABLED(CONFIG_OF) &&
- bridge->parent && bridge->parent->of_node) {
- of_dma_configure(&dev->dev, bridge->parent->of_node);
- } else if (has_acpi_companion(bridge)) {
- struct acpi_device *adev = to_acpi_device_node(bridge->fwnode);
- enum dev_dma_attr attr = acpi_get_dma_attr(adev);
-
- if (attr == DEV_DMA_NOT_SUPPORTED)
- dev_warn(&dev->dev, "DMA not supported.\n");
- else
- acpi_dma_configure(&dev->dev, attr);
- }
-
- pci_put_host_bridge_device(bridge);
-}
-
void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
{
int ret;
@@ -1933,7 +1906,6 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
dev->dev.dma_mask = &dev->dma_mask;
dev->dev.dma_parms = &dev->dma_parms;
dev->dev.coherent_dma_mask = 0xffffffffull;
- pci_dma_configure(dev);

pci_set_dma_max_seg_size(dev, 65536);
pci_set_dma_seg_boundary(dev, 0xffffffff);
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 0977317..4f3eece 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -728,6 +728,18 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
}
#endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */

+#ifdef CONFIG_HAS_DMA
+int dma_configure(struct device *dev);
+void dma_deconfigure(struct device *dev);
+#else
+static inline int dma_configure(struct device *dev)
+{
+ return 0;
+}
+
+static inline void dma_deconfigure(struct device *dev) {}
+#endif
+
/*
* Managed DMA API
*/
--
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