Claire Chang
2021-Apr-22 08:15 UTC
[Nouveau] [PATCH v5 16/16] of: Add plumbing for restricted DMA pool
If a device is not behind an IOMMU, we look up the device node and set
up the restricted DMA when the restricted-dma-pool is presented.
Signed-off-by: Claire Chang <tientzu at chromium.org>
---
drivers/of/address.c | 25 +++++++++++++++++++++++++
drivers/of/device.c | 3 +++
drivers/of/of_private.h | 5 +++++
3 files changed, 33 insertions(+)
diff --git a/drivers/of/address.c b/drivers/of/address.c
index 54f221dde267..fff3adfe4986 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -8,6 +8,7 @@
#include <linux/logic_pio.h>
#include <linux/module.h>
#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
#include <linux/sizes.h>
@@ -1109,6 +1110,30 @@ bool of_dma_is_coherent(struct device_node *np)
}
EXPORT_SYMBOL_GPL(of_dma_is_coherent);
+int of_dma_set_restricted_buffer(struct device *dev)
+{
+ struct device_node *node;
+ int count, i;
+
+ if (!dev->of_node)
+ return 0;
+
+ count = of_property_count_elems_of_size(dev->of_node,
"memory-region",
+ sizeof(phandle));
+ for (i = 0; i < count; i++) {
+ node = of_parse_phandle(dev->of_node, "memory-region", i);
+ /* There might be multiple memory regions, but only one
+ * restriced-dma-pool region is allowed.
+ */
+ if (of_device_is_compatible(node, "restricted-dma-pool") &&
+ of_device_is_available(node))
+ return of_reserved_mem_device_init_by_idx(
+ dev, dev->of_node, i);
+ }
+
+ return 0;
+}
+
/**
* of_mmio_is_nonposted - Check if device uses non-posted MMIO
* @np: device node
diff --git a/drivers/of/device.c b/drivers/of/device.c
index c5a9473a5fb1..d8d865223e51 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct
device_node *np,
arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
+ if (!iommu)
+ return of_dma_set_restricted_buffer(dev);
+
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);
diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h
index d717efbd637d..e9237f5eff48 100644
--- a/drivers/of/of_private.h
+++ b/drivers/of/of_private.h
@@ -163,12 +163,17 @@ struct bus_dma_region;
#if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA)
int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map);
+int of_dma_set_restricted_buffer(struct device *dev);
#else
static inline int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map)
{
return -ENODEV;
}
+static inline int of_dma_get_restricted_buffer(struct device *dev)
+{
+ return -ENODEV;
+}
#endif
#endif /* _LINUX_OF_PRIVATE_H */
--
2.31.1.368.gbe11c130af-goog
Claire Chang
2021-Apr-23 02:52 UTC
[Nouveau] [PATCH v5 16/16] of: Add plumbing for restricted DMA pool
On Thu, Apr 22, 2021 at 4:17 PM Claire Chang <tientzu at chromium.org> wrote:> > If a device is not behind an IOMMU, we look up the device node and set > up the restricted DMA when the restricted-dma-pool is presented. > > Signed-off-by: Claire Chang <tientzu at chromium.org> > --- > drivers/of/address.c | 25 +++++++++++++++++++++++++ > drivers/of/device.c | 3 +++ > drivers/of/of_private.h | 5 +++++ > 3 files changed, 33 insertions(+) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 54f221dde267..fff3adfe4986 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -8,6 +8,7 @@ > #include <linux/logic_pio.h> > #include <linux/module.h> > #include <linux/of_address.h> > +#include <linux/of_reserved_mem.h> > #include <linux/pci.h> > #include <linux/pci_regs.h> > #include <linux/sizes.h> > @@ -1109,6 +1110,30 @@ bool of_dma_is_coherent(struct device_node *np) > } > EXPORT_SYMBOL_GPL(of_dma_is_coherent); > > +int of_dma_set_restricted_buffer(struct device *dev) > +{ > + struct device_node *node; > + int count, i; > + > + if (!dev->of_node) > + return 0; > + > + count = of_property_count_elems_of_size(dev->of_node, "memory-region", > + sizeof(phandle)); > + for (i = 0; i < count; i++) { > + node = of_parse_phandle(dev->of_node, "memory-region", i); > + /* There might be multiple memory regions, but only one > + * restriced-dma-pool region is allowed. > + */ > + if (of_device_is_compatible(node, "restricted-dma-pool") && > + of_device_is_available(node)) > + return of_reserved_mem_device_init_by_idx( > + dev, dev->of_node, i); > + } > + > + return 0; > +} > + > /** > * of_mmio_is_nonposted - Check if device uses non-posted MMIO > * @np: device node > diff --git a/drivers/of/device.c b/drivers/of/device.c > index c5a9473a5fb1..d8d865223e51 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, > > arch_setup_dma_ops(dev, dma_start, size, iommu, coherent); > > + if (!iommu) > + return of_dma_set_restricted_buffer(dev); > + > return 0; > } > EXPORT_SYMBOL_GPL(of_dma_configure_id); > diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h > index d717efbd637d..e9237f5eff48 100644 > --- a/drivers/of/of_private.h > +++ b/drivers/of/of_private.h > @@ -163,12 +163,17 @@ struct bus_dma_region; > #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA) > int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map); > +int of_dma_set_restricted_buffer(struct device *dev); > #else > static inline int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map) > { > return -ENODEV; > } > +static inline int of_dma_get_restricted_buffer(struct device *dev)This one should be of_dma_set_restricted_buffer. Sorry for the typo.> +{ > + return -ENODEV; > +} > #endif > > #endif /* _LINUX_OF_PRIVATE_H */ > -- > 2.31.1.368.gbe11c130af-goog >
Robin Murphy
2021-Apr-23 13:35 UTC
[Nouveau] [PATCH v5 16/16] of: Add plumbing for restricted DMA pool
On 2021-04-22 09:15, Claire Chang wrote:> If a device is not behind an IOMMU, we look up the device node and set > up the restricted DMA when the restricted-dma-pool is presented. > > Signed-off-by: Claire Chang <tientzu at chromium.org> > --- > drivers/of/address.c | 25 +++++++++++++++++++++++++ > drivers/of/device.c | 3 +++ > drivers/of/of_private.h | 5 +++++ > 3 files changed, 33 insertions(+) > > diff --git a/drivers/of/address.c b/drivers/of/address.c > index 54f221dde267..fff3adfe4986 100644 > --- a/drivers/of/address.c > +++ b/drivers/of/address.c > @@ -8,6 +8,7 @@ > #include <linux/logic_pio.h> > #include <linux/module.h> > #include <linux/of_address.h> > +#include <linux/of_reserved_mem.h> > #include <linux/pci.h> > #include <linux/pci_regs.h> > #include <linux/sizes.h> > @@ -1109,6 +1110,30 @@ bool of_dma_is_coherent(struct device_node *np) > } > EXPORT_SYMBOL_GPL(of_dma_is_coherent); > > +int of_dma_set_restricted_buffer(struct device *dev) > +{ > + struct device_node *node; > + int count, i; > + > + if (!dev->of_node) > + return 0; > + > + count = of_property_count_elems_of_size(dev->of_node, "memory-region", > + sizeof(phandle)); > + for (i = 0; i < count; i++) { > + node = of_parse_phandle(dev->of_node, "memory-region", i); > + /* There might be multiple memory regions, but only one > + * restriced-dma-pool region is allowed. > + */What's the use-case for having multiple regions if the restricted pool is by definition the only one accessible? Robin.> + if (of_device_is_compatible(node, "restricted-dma-pool") && > + of_device_is_available(node)) > + return of_reserved_mem_device_init_by_idx( > + dev, dev->of_node, i); > + } > + > + return 0; > +} > + > /** > * of_mmio_is_nonposted - Check if device uses non-posted MMIO > * @np: device node > diff --git a/drivers/of/device.c b/drivers/of/device.c > index c5a9473a5fb1..d8d865223e51 100644 > --- a/drivers/of/device.c > +++ b/drivers/of/device.c > @@ -165,6 +165,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, > > arch_setup_dma_ops(dev, dma_start, size, iommu, coherent); > > + if (!iommu) > + return of_dma_set_restricted_buffer(dev); > + > return 0; > } > EXPORT_SYMBOL_GPL(of_dma_configure_id); > diff --git a/drivers/of/of_private.h b/drivers/of/of_private.h > index d717efbd637d..e9237f5eff48 100644 > --- a/drivers/of/of_private.h > +++ b/drivers/of/of_private.h > @@ -163,12 +163,17 @@ struct bus_dma_region; > #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA) > int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map); > +int of_dma_set_restricted_buffer(struct device *dev); > #else > static inline int of_dma_get_range(struct device_node *np, > const struct bus_dma_region **map) > { > return -ENODEV; > } > +static inline int of_dma_get_restricted_buffer(struct device *dev) > +{ > + return -ENODEV; > +} > #endif > > #endif /* _LINUX_OF_PRIVATE_H */ >