1. 29 9月, 2008 4 次提交
    • T
      libata: implement slave_link · b1c72916
      Tejun Heo 提交于
      Explanation taken from the comment of ata_slave_link_init().
      
       In libata, a port contains links and a link contains devices.  There
       is single host link but if a PMP is attached to it, there can be
       multiple fan-out links.  On SATA, there's usually a single device
       connected to a link but PATA and SATA controllers emulating TF based
       interface can have two - master and slave.
      
       However, there are a few controllers which don't fit into this
       abstraction too well - SATA controllers which emulate TF interface
       with both master and slave devices but also have separate SCR
       register sets for each device.  These controllers need separate links
       for physical link handling (e.g. onlineness, link speed) but should
       be treated like a traditional M/S controller for everything else
       (e.g. command issue, softreset).
      
       slave_link is libata's way of handling this class of controllers
       without impacting core layer too much.  For anything other than
       physical link handling, the default host link is used for both master
       and slave.  For physical link handling, separate @ap->slave_link is
       used.  All dirty details are implemented inside libata core layer.
       From LLD's POV, the only difference is that prereset, hardreset and
       postreset are called once more for the slave link, so the reset
       sequence looks like the following.
      
       prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
       softreset(M) -> postreset(M) -> postreset(S)
      
       Note that softreset is called only for the master.  Softreset resets
       both M/S by definition, so SRST on master should handle both (the
       standard method will work just fine).
      
      As slave_link excludes PMP support and only code paths which deal with
      the attributes of physical link are affected, all the changes are
      localized to libata.h, libata-core.c and libata-eh.c.
      
       * ata_is_host_link() updated so that slave_link is considered as host
         link too.
      
       * iterator extended to iterate over the slave_link when using the
         underbarred version.
      
       * force param handling updated such that devno 16 is mapped to the
         slave link/device.
      
       * ata_link_on/offline() updated to return the combined result from
         master and slave link.  ata_phys_link_on/offline() are the direct
         versions.
      
       * EH autopsy and report are performed separately for master slave
         links.  Reset is udpated to implement the above described reset
         sequence.
      
      Except for reset update, most changes are minor, many of them just
      modifying dev->link to ata_dev_phys_link(dev) or using phys online
      test instead.
      
      After this update, LLDs can take full advantage of per-dev SCR
      registers by simply turning on slave link.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      b1c72916
    • T
      libata: misc updates to prepare for slave link · b5b3fa38
      Tejun Heo 提交于
      * Add ATA_EH_ALL_ACTIONS.
      
      * Make sata_link_{on|off}_line() return bool instead of int.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      b5b3fa38
    • T
      libata: reimplement link iterator · aadffb68
      Tejun Heo 提交于
      Implement __ata_port_next_link() and reimplement
      __ata_port_for_each_link() and ata_port_for_each_link() using it.
      This removes relatively large inlined code and makes iteration easier
      to extend.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      aadffb68
    • T
      libata: make SCR access ops per-link · 82ef04fb
      Tejun Heo 提交于
      Logically, SCR access ops should take @link; however, there was no
      compelling reason to convert all SCR access ops when adding @link
      abstraction as there's one-to-one mapping between a port and a non-PMP
      link.  However, that assumption won't hold anymore with the scheduled
      addition of slave link.
      
      Make SCR access ops per-link.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      82ef04fb
  2. 26 9月, 2008 1 次提交
  3. 25 9月, 2008 18 次提交
  4. 24 9月, 2008 17 次提交