ACPI: Implement acpi_dma_configure

On DT based systems, the of_dma_configure() API implements DMA
configuration for a given device. On ACPI systems an API equivalent to
of_dma_configure() is missing which implies that it is currently not
possible to set-up DMA operations for devices through the ACPI generic
kernel layer.

This patch fills the gap by introducing acpi_dma_configure/deconfigure()
calls that for now are just wrappers around arch_setup_dma_ops() and
arch_teardown_dma_ops() and also updates ACPI and PCI core code to use
the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions.

Since acpi_dma_configure() is used to configure DMA operations, the
function initializes the dma/coherent_dma masks to sane default values
if the current masks are uninitialized (also to keep the default values
consistent with DT systems) to make sure the device has a complete
default DMA set-up.

The DMA range size passed to arch_setup_dma_ops() is sized according
to the device coherent_dma_mask (starting at address 0x0), mirroring the
DT probing path behaviour when a dma-ranges property is not provided
for the device being probed; this changes the current arch_setup_dma_ops()
call parameters in the ACPI probing case, but since arch_setup_dma_ops()
is a NOP on all architectures but ARM/ARM64 this patch does not change
the current kernel behaviour on them.

Signed-off-by: Lorenzo Pieralisi <[email protected]>
Acked-by: Bjorn Helgaas <[email protected]> [pci]
Acked-by: Rafael J. Wysocki <[email protected]>
Reviewed-by: Tomasz Nowicki <[email protected]>
Tested-by: Hanjun Guo <[email protected]>
Tested-by: Tomasz Nowicki <[email protected]>
Cc: Bjorn Helgaas <[email protected]>
Cc: Robin Murphy <[email protected]>
Cc: Tomasz Nowicki <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
5 files changed