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/openbmc/qemu/hw/usb/
H A Dlibhw.cdiff e2f89926f19d2940eda070542501f39f51a8c81f Tue Jun 26 23:50:42 CDT 2012 David Gibson <david@gibson.dropbear.id.au> usb: Convert usb_packet_{map, unmap} to universal DMA helpers

The USB UHCI and EHCI drivers were converted some time ago to use the
pci_dma_*() helper functions. However, this conversion was not complete
because in some places both these drivers do DMA via the usb_packet_map()
function in usb-libhw.c. That function directly used
cpu_physical_memory_map().

Now that the sglist code uses DMA wrappers properly, we can convert the
functions in usb-libhw.c, thus conpleting the conversion of UHCI and EHCI
to use the DMA wrappers.

Note that usb_packet_map() invokes dma_memory_map() with a NULL invalidate
callback function. When IOMMU support is added, this will mean that
usb_packet_map() and the corresponding usb_packet_unmap() must be called in
close proximity without dropping the qemu device lock - otherwise the guest
might invalidate IOMMU mappings while they are still in use by the device
code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
H A Dhcd-uhci.cdiff e2f89926f19d2940eda070542501f39f51a8c81f Tue Jun 26 23:50:42 CDT 2012 David Gibson <david@gibson.dropbear.id.au> usb: Convert usb_packet_{map, unmap} to universal DMA helpers

The USB UHCI and EHCI drivers were converted some time ago to use the
pci_dma_*() helper functions. However, this conversion was not complete
because in some places both these drivers do DMA via the usb_packet_map()
function in usb-libhw.c. That function directly used
cpu_physical_memory_map().

Now that the sglist code uses DMA wrappers properly, we can convert the
functions in usb-libhw.c, thus conpleting the conversion of UHCI and EHCI
to use the DMA wrappers.

Note that usb_packet_map() invokes dma_memory_map() with a NULL invalidate
callback function. When IOMMU support is added, this will mean that
usb_packet_map() and the corresponding usb_packet_unmap() must be called in
close proximity without dropping the qemu device lock - otherwise the guest
might invalidate IOMMU mappings while they are still in use by the device
code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
H A Dhcd-ehci.cdiff e2f89926f19d2940eda070542501f39f51a8c81f Tue Jun 26 23:50:42 CDT 2012 David Gibson <david@gibson.dropbear.id.au> usb: Convert usb_packet_{map, unmap} to universal DMA helpers

The USB UHCI and EHCI drivers were converted some time ago to use the
pci_dma_*() helper functions. However, this conversion was not complete
because in some places both these drivers do DMA via the usb_packet_map()
function in usb-libhw.c. That function directly used
cpu_physical_memory_map().

Now that the sglist code uses DMA wrappers properly, we can convert the
functions in usb-libhw.c, thus conpleting the conversion of UHCI and EHCI
to use the DMA wrappers.

Note that usb_packet_map() invokes dma_memory_map() with a NULL invalidate
callback function. When IOMMU support is added, this will mean that
usb_packet_map() and the corresponding usb_packet_unmap() must be called in
close proximity without dropping the qemu device lock - otherwise the guest
might invalidate IOMMU mappings while they are still in use by the device
code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>