target/linux/sunxi/patches-3.13/160-ahci-add-pre-start-hook.patch

   1 From 3eec76bc21d78e56ac8404b59f29dd9dbbd1528a Mon Sep 17 00:00:00 2001
   2 From: Oliver Schinagl <oliver@schinagl.nl>
   3 Date: Mon, 2 Dec 2013 16:13:32 +0100
   4 Subject: [PATCH] libahci: Add a pre ahci_start_engine hook
   5
   6 Allwinner A10 and A20 ARM SoCs have an AHCI sata controller which need a
   7 special register to be poked before starting the DMA engine.
   8
   9 This register gets reset on an ahci_stop_engine call, so there is no other
  10 place then ahci_start_engine where this poking can be done.
  11
  12 This commit adds a pre ahci_start_engine hook for use by the Allwinner AHCI
  13 driver (and potentially other drivers in the future).
  14
  15 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  16 ---
  17  drivers/ata/ahci.h    | 2 ++
  18  drivers/ata/libahci.c | 4 ++++
  19  2 files changed, 6 insertions(+)
  20
  21 --- a/drivers/ata/ahci.h
  22 +++ b/drivers/ata/ahci.h
  23 @@ -323,6 +323,8 @@ struct ahci_host_priv {
  24         u32                     em_msg_type;    /* EM message type */
  25         struct clk              *clk;           /* Only for platforms supporting clk */
  26         void                    *plat_data;     /* Other platform data */
  27 +       /* Optional pre ahci_start_engine hook */
  28 +       void                    (*pre_start_engine)(struct ata_port *ap);
  29  };
  30
  31  extern int ahci_ignore_sss;
  32 --- a/drivers/ata/libahci.c
  33 +++ b/drivers/ata/libahci.c
  34 @@ -568,8 +568,12 @@ static int ahci_scr_write(struct ata_lin
  35  void ahci_start_engine(struct ata_port *ap)
  36  {
  37         void __iomem *port_mmio = ahci_port_base(ap);
  38 +       struct ahci_host_priv *hpriv = ap->host->private_data;
  39         u32 tmp;
  40
  41 +       if (hpriv->pre_start_engine)
  42 +               hpriv->pre_start_engine(ap);
  43 +
  44         /* start DMA */
  45         tmp = readl(port_mmio + PORT_CMD);
  46         tmp |= PORT_CMD_START;