Merge tag 'omapdss-for-3.7' of git://gitorious.org/linux-omap-dss2/linux into fbdev-next

Omapdss driver changes for the 3.7 merge window.

Notable changes:

* Basic writeback support for DISPC level. Writeback is not yet usable, though,
  as we need higher level code to actually expose the writeback feature to
  userspace.
* Rewriting the omapdss output drivers. We're trying to remove the hard links
  between the omapdss and the panels, and this rewrite work moves us closer to
  that goal.
* Cleanup and restructuring patches that have been made while working on device
  tree support for omapdss. Device tree support is still some way ahead, but
  these patches are good cleanups in themselves.
* Basic OMAP5 DSS support for DPI and DSI outputs.
* Workaround for the problem that GFX overlay's fifo is too small for high
  resolution scenarios, causing underflows.
* Cleanups that remove dependencies to omap platform code.

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/mips/pci/pci-ar724x.c b/arch/mips/pci/pci-ar724x.c
index 414a7459858d..86d77a666458 100644
--- a/arch/mips/pci/pci-ar724x.c
+++ b/arch/mips/pci/pci-ar724x.c
@@ -23,9 +23,12 @@
 #define AR724X_PCI_MEM_BASE	0x10000000
 #define AR724X_PCI_MEM_SIZE	0x08000000
 
+#define AR724X_PCI_REG_RESET		0x18
 #define AR724X_PCI_REG_INT_STATUS	0x4c
 #define AR724X_PCI_REG_INT_MASK		0x50
 
+#define AR724X_PCI_RESET_LINK_UP	BIT(0)
+
 #define AR724X_PCI_INT_DEV0		BIT(14)
 
 #define AR724X_PCI_IRQ_COUNT		1
@@ -38,6 +41,15 @@ static void __iomem *ar724x_pci_ctrl_base;
 
 static u32 ar724x_pci_bar0_value;
 static bool ar724x_pci_bar0_is_cached;
+static bool ar724x_pci_link_up;
+
+static inline bool ar724x_pci_check_link(void)
+{
+	u32 reset;
+
+	reset = __raw_readl(ar724x_pci_ctrl_base + AR724X_PCI_REG_RESET);
+	return reset & AR724X_PCI_RESET_LINK_UP;
+}
 
 static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
 			    int size, uint32_t *value)
@@ -46,6 +58,9 @@ static int ar724x_pci_read(struct pci_bus *bus, unsigned int devfn, int where,
 	void __iomem *base;
 	u32 data;
 
+	if (!ar724x_pci_link_up)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
 	if (devfn)
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
@@ -96,6 +111,9 @@ static int ar724x_pci_write(struct pci_bus *bus, unsigned int devfn, int where,
 	u32 data;
 	int s;
 
+	if (!ar724x_pci_link_up)
+		return PCIBIOS_DEVICE_NOT_FOUND;
+
 	if (devfn)
 		return PCIBIOS_DEVICE_NOT_FOUND;
 
@@ -280,6 +298,10 @@ int __init ar724x_pcibios_init(int irq)
 	if (ar724x_pci_ctrl_base == NULL)
 		goto err_unmap_devcfg;
 
+	ar724x_pci_link_up = ar724x_pci_check_link();
+	if (!ar724x_pci_link_up)
+		pr_warn("ar724x: PCIe link is down\n");
+
 	ar724x_pci_irq_init(irq);
 	register_pci_controller(&ar724x_pci_controller);