tile pci: enable IOMMU to support DMA for legacy devices

[profile/ivi/kernel-adaptation-intel-automotive.git] / arch / tile / include / asm / pci.h

diff --git a/arch/tile/include/asm/pci.h b/arch/tile/include/asm/pci.h
index 2c224c4..553b7ff 100644 (file)
--- a/arch/tile/include/asm/pci.h
+++ b/arch/tile/include/asm/pci.h
@@ -15,6 +15,7 @@
 #ifndef _ASM_TILE_PCI_H
 #define _ASM_TILE_PCI_H
 
+#include <linux/dma-mapping.h>
 #include <linux/pci.h>
 #include <linux/numa.h>
 #include <asm-generic/pci_iomap.h>
@@ -53,6 +54,16 @@ static inline void pci_iounmap(struct pci_dev *dev, void __iomem *addr) {}
 
 #define        TILE_NUM_PCIE   2
 
+/*
+ * The hypervisor maps the entirety of CPA-space as bus addresses, so
+ * bus addresses are physical addresses.  The networking and block
+ * device layers use this boolean for bounce buffer decisions.
+ */
+#define PCI_DMA_BUS_IS_PHYS     1
+
+/* generic pci stuff */
+#include <asm-generic/pci.h>
+
 #else
 
 #include <asm/page.h>
@@ -85,7 +96,47 @@ static inline void pci_iounmap(struct pci_dev *dev, void __iomem *addr) {}
 /*
  * Each Mem-Map interrupt region occupies 4KB.
  */
-#define        MEM_MAP_INTR_REGION_SIZE        (1<< TRIO_MAP_MEM_LIM__ADDR_SHIFT)
+#define        MEM_MAP_INTR_REGION_SIZE        (1 << TRIO_MAP_MEM_LIM__ADDR_SHIFT)
+
+/*
+ * Allocate the PCI BAR window right below 4GB.
+ */
+#define        TILE_PCI_BAR_WINDOW_TOP         (1ULL << 32)
+
+/*
+ * Allocate 1GB for the PCI BAR window.
+ */
+#define        TILE_PCI_BAR_WINDOW_SIZE        (1 << 30)
+
+/*
+ * This is the highest bus address targeting the host memory that
+ * can be generated by legacy PCI devices with 32-bit or less
+ * DMA capability, dictated by the BAR window size and location.
+ */
+#define        TILE_PCI_MAX_DIRECT_DMA_ADDRESS \
+       (TILE_PCI_BAR_WINDOW_TOP - TILE_PCI_BAR_WINDOW_SIZE - 1)
+
+/*
+ * We shift the PCI bus range for all the physical memory up by the whole PA
+ * range. The corresponding CPA of an incoming PCI request will be the PCI
+ * address minus TILE_PCI_MEM_MAP_BASE_OFFSET. This also implies
+ * that the 64-bit capable devices will be given DMA addresses as
+ * the CPA plus TILE_PCI_MEM_MAP_BASE_OFFSET. To support 32-bit
+ * devices, we create a separate map region that handles the low
+ * 4GB.
+ */
+#define        TILE_PCI_MEM_MAP_BASE_OFFSET    (1ULL << CHIP_PA_WIDTH())
+
+/*
+ * End of the PCI memory resource.
+ */
+#define        TILE_PCI_MEM_END        \
+               ((1ULL << CHIP_PA_WIDTH()) + TILE_PCI_BAR_WINDOW_TOP)
+
+/*
+ * Start of the PCI memory resource.
+ */
+#define        TILE_PCI_MEM_START      (TILE_PCI_MEM_END - TILE_PCI_BAR_WINDOW_SIZE)
 
 /*
  * Structure of a PCI controller (host bridge) on Gx.
@@ -108,6 +159,8 @@ struct pci_controller {
        int index;              /* PCI domain number */
        struct pci_bus *root_bus;
 
+       uint64_t mem_offset;    /* cpu->bus memory mapping offset. */
+
        int last_busno;
 
        struct pci_ops *ops;
@@ -126,14 +179,22 @@ extern gxio_trio_context_t trio_contexts[TILEGX_NUM_TRIO];
 
 extern void pci_iounmap(struct pci_dev *dev, void __iomem *);
 
-#endif /* __tilegx__ */
+extern void
+pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
+                       struct resource *res);
+
+extern void
+pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
+                       struct pci_bus_region *region);
 
 /*
- * The hypervisor maps the entirety of CPA-space as bus addresses, so
- * bus addresses are physical addresses.  The networking and block
- * device layers use this boolean for bounce buffer decisions.
+ * The PCI address space does not equal the physical memory address
+ * space (we have an IOMMU). The IDE and SCSI device layers use this
+ * boolean for bounce buffer decisions.
  */
-#define PCI_DMA_BUS_IS_PHYS     1
+#define PCI_DMA_BUS_IS_PHYS     0
+
+#endif /* __tilegx__ */
 
 int __init tile_pci_init(void);
 int __init pcibios_init(void);
@@ -169,7 +230,4 @@ static inline int pcibios_assign_all_busses(void)
 /* implement the pci_ DMA API in terms of the generic device dma_ one */
 #include <asm-generic/pci-dma-compat.h>
 
-/* generic pci stuff */
-#include <asm-generic/pci.h>
-
 #endif /* _ASM_TILE_PCI_H */