This patch adds support to setup DMA coherency for PCI device using
the ACPI _CCA attribute. According to the ACPI spec, the _CCA attribute
is required for ARM64. Therefore, this patch is a pre-req for ACPI PCI
support for ARM64 which is currently in development.
Also, this should not affect other architectures that does not define
CONFIG_ACPI_CCA_REQUIRED, since the default value is coherent.
I have included the following patch from Jeremy before cleaning up
the acpi_check_dma() function (in patch 2).
http://www.spinics.net/lists/linux-usb/msg128582.html)
Changes from V2: (https://lkml.org/lkml/2015/8/25/549)
* Return -ENOSUPP instead of -1 (per Rafael's suggestion)
* Add WARN() when fail to setup DMA for PCI device when booting
ACPI (per Arnd's suggestion)
* Added Acked-by from Rob.
* Minor clean up
Changes from V1: (https://lkml.org/lkml/2015/8/13/182)
* Include patch 1 from Jeremy to enable support for _CCA=0
* Clean up acpi_check_dma() per Bjorn suggestions
* Split the original V1 patch into two patches (patch 3 and 4)
Jeremy Linton (1):
Honor ACPI _CCA attribute setting
Suravee Suthikulpanit (3):
ACPI/scan: Clean up acpi_check_dma
PCI: OF: Move of_pci_dma_configure() to pci_dma_configure()
PCI: ACPI: Add support for PCI device DMA coherency
drivers/acpi/acpi_platform.c | 7 ++++++-
drivers/acpi/glue.c | 6 +++---
drivers/acpi/scan.c | 39 +++++++++++++++++++++++++++++++++++++++
drivers/base/property.c | 10 +++++++---
drivers/of/of_pci.c | 20 --------------------
drivers/pci/probe.c | 35 +++++++++++++++++++++++++++++++++--
include/acpi/acpi_bus.h | 35 ++---------------------------------
include/linux/acpi.h | 4 ++--
include/linux/of_pci.h | 3 ---
9 files changed, 92 insertions(+), 67 deletions(-)
--
2.1.0
From: Jeremy Linton <[email protected]>
ACPI configurations can now mark devices as noncoherent,
support that choice.
NOTE: This is required to support USB on ARM Juno Development Board.
Signed-off-by: Jeremy Linton <[email protected]>
Signed-off-by: Suravee Suthikulpanit <[email protected]>
CC: Bjorn Helgaas <[email protected]>
CC: Catalin Marinas <[email protected]>
CC: Rob Herring <[email protected]>
CC: Will Deacon <[email protected]>
CC: Rafael J. Wysocki <[email protected]>
---
include/acpi/acpi_bus.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 83061ca..7ecb8e4 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -399,7 +399,7 @@ static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent)
* case 1. Do not support and disable DMA.
* case 2. Support but rely on arch-specific cache maintenance for
* non-coherence DMA operations.
- * Currently, we implement case 1 above.
+ * Currently, we implement case 2 above.
*
* For the case when _CCA is missing (i.e. cca_seen=0) and
* platform specifies ACPI_CCA_REQUIRED, we do not support DMA,
@@ -407,7 +407,8 @@ static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent)
*
* See acpi_init_coherency() for more info.
*/
- if (adev->flags.coherent_dma) {
+ if (adev->flags.coherent_dma ||
+ (adev->flags.cca_seen && IS_ENABLED(CONFIG_ARM64))) {
ret = true;
if (coherent)
*coherent = adev->flags.coherent_dma;
--
2.1.0
The original name of acpi_check_dma() function does not clearly tell what
exactly it is checking. Also, returning two boolean values (one to indicate
device is DMA capability, and the other to inidicate device coherency
attribute) can be confusing.
So, in order to simplify the function, this patch renames acpi_check_dma()
to acpi_check_dma_coherency() to clearly indicate the purpose of this
function, and only returns an integer where -1 means DMA not supported,
1 means coherent DMA, and 0 means non-coherent DMA.
Also, this patch moves the function into drivers/acpi/scan.c since
it is easier to follow the logic in the acpi_init_coherency() in the
same file here.
Signed-off-by: Suravee Suthikulpanit <[email protected]>
Suggested-by: Bjorn Helgaas <[email protected]>
Suggested-by: Rafael J. Wysocki <[email protected]>
CC: Catalin Marinas <[email protected]>
CC: Rob Herring <[email protected]>
CC: Will Deacon <[email protected]>
---
drivers/acpi/acpi_platform.c | 7 ++++++-
drivers/acpi/glue.c | 6 +++---
drivers/acpi/scan.c | 39 +++++++++++++++++++++++++++++++++++++++
drivers/base/property.c | 10 +++++++---
include/acpi/acpi_bus.h | 36 ++----------------------------------
include/linux/acpi.h | 4 ++--
6 files changed, 59 insertions(+), 43 deletions(-)
diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c
index 06a67d5..0b17a78 100644
--- a/drivers/acpi/acpi_platform.c
+++ b/drivers/acpi/acpi_platform.c
@@ -103,7 +103,12 @@ struct platform_device *acpi_create_platform_device(struct acpi_device *adev)
pdevinfo.res = resources;
pdevinfo.num_res = count;
pdevinfo.fwnode = acpi_fwnode_handle(adev);
- pdevinfo.dma_mask = acpi_check_dma(adev, NULL) ? DMA_BIT_MASK(32) : 0;
+
+ if (acpi_check_dma_coherency(adev) < 0)
+ pdevinfo.dma_mask = 0;
+ else
+ pdevinfo.dma_mask = DMA_BIT_MASK(32);
+
pdev = platform_device_register_full(&pdevinfo);
if (IS_ERR(pdev))
dev_err(&adev->dev, "platform device creation failed: %ld\n",
diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c
index b9657af..9be7f0f 100644
--- a/drivers/acpi/glue.c
+++ b/drivers/acpi/glue.c
@@ -168,7 +168,6 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
struct list_head *physnode_list;
unsigned int node_id;
int retval = -EINVAL;
- bool coherent;
if (has_acpi_companion(dev)) {
if (acpi_dev) {
@@ -225,8 +224,9 @@ int acpi_bind_one(struct device *dev, struct acpi_device *acpi_dev)
if (!has_acpi_companion(dev))
ACPI_COMPANION_SET(dev, acpi_dev);
- if (acpi_check_dma(acpi_dev, &coherent))
- arch_setup_dma_ops(dev, 0, 0, NULL, coherent);
+ retval = acpi_check_dma_coherency(acpi_dev);
+ if (retval >= 0)
+ arch_setup_dma_ops(dev, 0, 0, NULL, retval);
acpi_physnode_link_name(physical_node_name, node_id);
retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index ec25635..1d68289 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2182,6 +2182,45 @@ void acpi_free_pnp_ids(struct acpi_device_pnp *pnp)
kfree(pnp->unique_id);
}
+/**
+ * acpi_check_dma_coherency - Check DMA coherency for the specified device.
+ * @adev: The pointer to acpi device to check coherency attribute
+ *
+ * Return -ENOTSUPP if DMA is not supported. Otherwise, return 1 if the
+ * device support coherent DMA, or 0 for non-coherent DMA.
+ */
+int acpi_check_dma_coherency(struct acpi_device *adev)
+{
+ int ret = -ENOTSUPP;
+
+ if (!adev)
+ return ret;
+
+ /**
+ * Currently, we only support _CCA=1 (i.e. coherent_dma=1)
+ * This should be equivalent to specifying dma-coherent for
+ * a device in OF.
+ *
+ * For the case when _CCA=0 (i.e. coherent_dma=0 && cca_seen=1),
+ * we have two choices:
+ * 1. Do not support and disable DMA.
+ * 2. Support but rely on arch-specific cache maintenance for
+ * non-coherenje DMA operations.
+ * Currently, we implement case 2 above.
+ *
+ * For the case when _CCA is missing (i.e. cca_seen=0) and
+ * platform specifies ACPI_CCA_REQUIRED, we do not support DMA,
+ * and fallback to arch-specific default handling.
+ *
+ * See acpi_init_coherency() for more info.
+ */
+ if (!adev->flags.cca_seen && IS_ENABLED(CONFIG_ACPI_CCA_REQUIRED))
+ return ret;
+
+ return adev->flags.coherent_dma;
+}
+EXPORT_SYMBOL_GPL(acpi_check_dma_coherency);
+
static void acpi_init_coherency(struct acpi_device *adev)
{
unsigned long long cca = 0;
diff --git a/drivers/base/property.c b/drivers/base/property.c
index f3f6d16..cd45dfc 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -525,10 +525,14 @@ bool device_dma_is_coherent(struct device *dev)
{
bool coherent = false;
- if (IS_ENABLED(CONFIG_OF) && dev->of_node)
+ if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
coherent = of_dma_is_coherent(dev->of_node);
- else
- acpi_check_dma(ACPI_COMPANION(dev), &coherent);
+ } else {
+ int ret = acpi_check_dma_coherency(ACPI_COMPANION(dev));
+
+ if (ret >= 0)
+ coherent = ret;
+ }
return coherent;
}
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 7ecb8e4..baf43ea 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -382,40 +382,6 @@ struct acpi_device {
void (*remove)(struct acpi_device *);
};
-static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent)
-{
- bool ret = false;
-
- if (!adev)
- return ret;
-
- /**
- * Currently, we only support _CCA=1 (i.e. coherent_dma=1)
- * This should be equivalent to specifyig dma-coherent for
- * a device in OF.
- *
- * For the case when _CCA=0 (i.e. coherent_dma=0 && cca_seen=1),
- * There are two cases:
- * case 1. Do not support and disable DMA.
- * case 2. Support but rely on arch-specific cache maintenance for
- * non-coherence DMA operations.
- * Currently, we implement case 2 above.
- *
- * For the case when _CCA is missing (i.e. cca_seen=0) and
- * platform specifies ACPI_CCA_REQUIRED, we do not support DMA,
- * and fallback to arch-specific default handling.
- *
- * See acpi_init_coherency() for more info.
- */
- if (adev->flags.coherent_dma ||
- (adev->flags.cca_seen && IS_ENABLED(CONFIG_ARM64))) {
- ret = true;
- if (coherent)
- *coherent = adev->flags.coherent_dma;
- }
- return ret;
-}
-
static inline bool is_acpi_node(struct fwnode_handle *fwnode)
{
return fwnode && fwnode->type == FWNODE_ACPI;
@@ -640,6 +606,8 @@ static inline bool acpi_device_can_poweroff(struct acpi_device *adev)
return adev->power.states[ACPI_STATE_D3_COLD].flags.valid;
}
+int acpi_check_dma_coherency(struct acpi_device *adev);
+
#else /* CONFIG_ACPI */
static inline int register_acpi_bus_type(void *bus) { return 0; }
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index d2445fa..d350c9e 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -562,9 +562,9 @@ static inline int acpi_device_modalias(struct device *dev,
return -ENODEV;
}
-static inline bool acpi_check_dma(struct acpi_device *adev, bool *coherent)
+static inline int acpi_check_dma_coherency(struct acpi_device *adev)
{
- return false;
+ return -ENOTSUPP;
}
#define ACPI_PTR(_ptr) (NULL)
--
2.1.0
This patch move of_pci_dma_configure() to a more generic
pci_dma_configure(), which can be extended by non-OF code (e.g. ACPI).
This has no functional change.
Signed-off-by: Suravee Suthikulpanit <[email protected]>
Acked-by: Rob Herring <[email protected]>
CC: Bjorn Helgaas <[email protected]>
CC: Catalin Marinas <[email protected]>
CC: Will Deacon <[email protected]>
CC: Rafael J. Wysocki <[email protected]>
CC: Murali Karicheri <[email protected]>
---
drivers/of/of_pci.c | 20 --------------------
drivers/pci/probe.c | 27 +++++++++++++++++++++++++--
include/linux/of_pci.h | 3 ---
3 files changed, 25 insertions(+), 25 deletions(-)
diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
index 5751dc5..b66ee4e 100644
--- a/drivers/of/of_pci.c
+++ b/drivers/of/of_pci.c
@@ -117,26 +117,6 @@ int of_get_pci_domain_nr(struct device_node *node)
}
EXPORT_SYMBOL_GPL(of_get_pci_domain_nr);
-/**
- * of_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 of host bridge's parent (if any).
- */
-void of_pci_dma_configure(struct pci_dev *pci_dev)
-{
- struct device *dev = &pci_dev->dev;
- struct device *bridge = pci_get_host_bridge_device(pci_dev);
-
- if (!bridge->parent)
- return;
-
- of_dma_configure(dev, bridge->parent->of_node);
- pci_put_host_bridge_device(bridge);
-}
-EXPORT_SYMBOL_GPL(of_pci_dma_configure);
-
#if defined(CONFIG_OF_ADDRESS)
/**
* of_pci_get_host_bridge_resources - Parse PCI host bridge resources from DT
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index cefd636..4de6594 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -6,12 +6,14 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
-#include <linux/of_pci.h>
+#include <linux/of_device.h>
#include <linux/pci_hotplug.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/cpumask.h>
#include <linux/pci-aspm.h>
+#include <linux/acpi.h>
+#include <linux/property.h>
#include <asm-generic/pci-bridge.h>
#include "pci.h"
@@ -1544,6 +1546,27 @@ static void pci_init_capabilities(struct pci_dev *dev)
pci_enable_acs(dev);
}
+/**
+ * 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 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) && dev->dev.of_node) {
+ if (!bridge->parent)
+ return;
+
+ of_dma_configure(&dev->dev, bridge->parent->of_node);
+ }
+
+ pci_put_host_bridge_device(bridge);
+}
+
void pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
{
int ret;
@@ -1557,7 +1580,7 @@ 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;
- of_pci_dma_configure(dev);
+ pci_dma_configure(dev);
pci_set_dma_max_seg_size(dev, 65536);
pci_set_dma_seg_boundary(dev, 0xffffffff);
diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
index 29fd3fe..ce0e5ab 100644
--- a/include/linux/of_pci.h
+++ b/include/linux/of_pci.h
@@ -16,7 +16,6 @@ int of_pci_get_devfn(struct device_node *np);
int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
int of_get_pci_domain_nr(struct device_node *node);
-void of_pci_dma_configure(struct pci_dev *pci_dev);
#else
static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
{
@@ -51,8 +50,6 @@ of_get_pci_domain_nr(struct device_node *node)
{
return -1;
}
-
-static inline void of_pci_dma_configure(struct pci_dev *pci_dev) { }
#endif
#if defined(CONFIG_OF_ADDRESS)
--
2.1.0
This patch adds support for setting up PCI device DMA coherency from
ACPI _CCA object that should normally be specified in the DSDT node
of its PCI host bridge.
Signed-off-by: Suravee Suthikulpanit <[email protected]>
CC: Bjorn Helgaas <[email protected]>
CC: Catalin Marinas <[email protected]>
CC: Rob Herring <[email protected]>
CC: Will Deacon <[email protected]>
CC: Rafael J. Wysocki <[email protected]>
CC: Murali Karicheri <[email protected]>
---
drivers/pci/probe.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 4de6594..7cfd8e2 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1551,17 +1551,25 @@ static void pci_init_capabilities(struct pci_dev *dev)
* @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 of host bridge's parent (if any).
+ * 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) && dev->dev.of_node) {
- if (!bridge->parent)
- return;
-
- of_dma_configure(&dev->dev, bridge->parent->of_node);
+ if (bridge->parent)
+ of_dma_configure(&dev->dev,
+ bridge->parent->of_node);
+ } else if (has_acpi_companion(bridge)) {
+ struct acpi_device *adev = to_acpi_node(bridge->fwnode);
+ int ret = acpi_check_dma_coherency(adev);
+
+ if (ret < 0)
+ WARN(1, FW_BUG "PCI device %s fail to setup DMA.\n",
+ pci_name(dev));
+ else
+ arch_setup_dma_ops(&dev->dev, 0, 0, NULL, ret);
}
pci_put_host_bridge_device(bridge);
--
2.1.0