This directory contains the implementation of Genode's AHCI driver

Behavior
--------

The driver supports x86 32/64 bit platforms and the Exynos5 SOC. If
more than one AHCI controller is present, the first one will be used.
Each active device on each AHCI port will be represented by a Genode
block session. The server must be configured via a policy, that states
which client can access a certain device:


!<start name="ahci">
!  <binary name="ahci_drv" />
!  <resource name="RAM" quantum="10M" />
!  <provides><service name="Block" /></provides> }
!  <route>
!    <any-service> <parent /> <any-child /> </any-service>
!  </route>
!  <config atapi="no">
!    <!-- use model and serial number -->
!    <policy label_prefix="test-ahci" model="QEMU HARDDISK" serial="QM00005" writeable="yes" />
!    <!-- use controller port number -->
!    <policy label_prefix="bench" device="1" writeable="yes" />
!    <!-- read-only access -->
!    <policy label_prefix="boot_fs" device="2"/>
!  </config>
!</start>

In the example above, a session request labeled with "test-ahci" gains access to
a device with certain model and serial numbers, "bench" gains access to
device at port 1, and finally the session "boot_fs" gains read-only access to
port 2. ATAPI support is by default disabled and can be enabled by
setting the config attribute "atapi" to "yes".

ahci_drv supports reporting of active ports, which can be enabled via
configuration sub-node like follows.

!<report ports="yes"/>

The report structure is depicted by the following example.

! <ports>
!   <port num="0" type="ATA" block_count="32768" block_size="512"
!     model="QEMU HARDDISK" serial="QM00005"/>
!   <port num="1" type="ATAPI"/>
!   <port num="2" type="ATA" block_count="32768" block_size="512"
!     model="QEMU HARDDISK" serial="QM00009"/>
! </ports>
