target/linux/mvebu/patches-3.10/0197-xhci-fix-dma-mask-setup-in-xhci.c.patch

   1 From 5cb802766e9cdc9a56e8ce8e4686692ebbcfb5cc Mon Sep 17 00:00:00 2001
   2 From: Xenia Ragiadakou <burzalodowa@gmail.com>
   3 Date: Mon, 23 Dec 2013 16:59:02 +0100
   4 Subject: [PATCH 197/203] xhci: fix dma mask setup in xhci.c
   5
   6 The function dma_set_mask() tests internally whether the dma_mask pointer
   7 for the device is initialized and fails if the dma_mask pointer is NULL.
   8 On pci platforms, the device dma_mask pointer is initialized, when pci
   9 devices are enumerated, to point to the pci_dev->dma_mask which is 0xffffffff.
  10 However, for non-pci platforms, the dma_mask pointer may not be initialized
  11 and in that case dma_set_mask() will fail.
  12
  13 This patch initializes the dma_mask and the coherent_dma_mask to 32bits
  14 in xhci_plat_probe(), before the call to usb_create_hcd() that sets the
  15 "uses_dma" flag for the usb bus and the call to usb_add_hcd() that creates
  16 coherent dma pools for the usb hcd.
  17
  18 Moreover, a call to dma_set_mask() does not set the device coherent_dma_mask.
  19 Since the xhci-hcd driver calls dma_alloc_coherent() and dma_pool_alloc()
  20 to allocate consistent DMA memory blocks, the coherent DMA address mask
  21 has to be set explicitly.
  22
  23 This patch sets the coherent_dma_mask to 64bits in xhci_gen_setup() when
  24 the xHC is capable for 64-bit DMA addressing.
  25
  26 If dma_set_mask() succeeds, for a given bitmask, it is guaranteed that
  27 the given bitmask is also supported for consistent DMA mappings.
  28
  29 Other changes introduced in this patch are:
  30
  31 - The return value of dma_set_mask() is checked to ensure that the required
  32   dma bitmask conforms with the host system's addressing capabilities.
  33
  34 - The dma_mask setup code for the non-primary hcd was removed since both
  35   primary and non-primary hcd refer to the same generic device whose
  36   dma_mask and coherent_dma_mask are already set during the setup of
  37   the primary hcd.
  38
  39 - The code for reading the HCCPARAMS register to find out the addressing
  40   capabilities of xHC was removed since its value is already cached in
  41   xhci->hccparams.
  42
  43 - hcd->self.controller was replaced with the dev variable since it is
  44   already available.
  45
  46 Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com>
  47 Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
  48
  49 Conflicts:
  50         drivers/usb/host/xhci-plat.c
  51 ---
  52  drivers/usb/host/xhci-plat.c | 10 ++++++++++
  53  drivers/usb/host/xhci.c      | 19 +++++--------------
  54  2 files changed, 15 insertions(+), 14 deletions(-)
  55
  56 --- a/drivers/usb/host/xhci-plat.c
  57 +++ b/drivers/usb/host/xhci-plat.c
  58 @@ -15,6 +15,7 @@
  59  #include <linux/module.h>
  60  #include <linux/slab.h>
  61  #include <linux/of.h>
  62 +#include <linux/dma-mapping.h>
  63
  64  #include "xhci.h"
  65
  66 @@ -105,6 +106,15 @@ static int xhci_plat_probe(struct platfo
  67         if (!res)
  68                 return -ENODEV;
  69
  70 +       /* Initialize dma_mask and coherent_dma_mask to 32-bits */
  71 +       ret = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
  72 +       if (ret)
  73 +               return ret;
  74 +       if (!pdev->dev.dma_mask)
  75 +               pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
  76 +       else
  77 +               dma_set_mask(&pdev->dev, DMA_BIT_MASK(32));
  78 +
  79         hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
  80         if (!hcd)
  81                 return -ENOMEM;
  82 --- a/drivers/usb/host/xhci.c
  83 +++ b/drivers/usb/host/xhci.c
  84 @@ -4654,7 +4654,6 @@ int xhci_gen_setup(struct usb_hcd *hcd,
  85         struct xhci_hcd         *xhci;
  86         struct device           *dev = hcd->self.controller;
  87         int                     retval;
  88 -       u32                     temp;
  89
  90         /* Accept arbitrarily long scatter-gather lists */
  91         hcd->self.sg_tablesize = ~0;
  92 @@ -4682,14 +4681,6 @@ int xhci_gen_setup(struct usb_hcd *hcd,
  93                 /* xHCI private pointer was set in xhci_pci_probe for the second
  94                  * registered roothub.
  95                  */
  96 -               xhci = hcd_to_xhci(hcd);
  97 -               temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
  98 -               if (HCC_64BIT_ADDR(temp)) {
  99 -                       xhci_dbg(xhci, "Enabling 64-bit DMA addresses.\n");
 100 -                       dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64));
 101 -               } else {
 102 -                       dma_set_mask(hcd->self.controller, DMA_BIT_MASK(32));
 103 -               }
 104                 return 0;
 105         }
 106
 107 @@ -4728,12 +4719,12 @@ int xhci_gen_setup(struct usb_hcd *hcd,
 108                 goto error;
 109         xhci_dbg(xhci, "Reset complete\n");
 110
 111 -       temp = xhci_readl(xhci, &xhci->cap_regs->hcc_params);
 112 -       if (HCC_64BIT_ADDR(temp)) {
 113 +       /* Set dma_mask and coherent_dma_mask to 64-bits,
 114 +        * if xHC supports 64-bit addressing */
 115 +       if (HCC_64BIT_ADDR(xhci->hcc_params) &&
 116 +                       !dma_set_mask(dev, DMA_BIT_MASK(64))) {
 117                 xhci_dbg(xhci, "Enabling 64-bit DMA addresses.\n");
 118 -               dma_set_mask(hcd->self.controller, DMA_BIT_MASK(64));
 119 -       } else {
 120 -               dma_set_mask(hcd->self.controller, DMA_BIT_MASK(32));
 121 +               dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
 122         }
 123
 124         xhci_dbg(xhci, "Calling HCD init\n");