[PATCH 1/3] PCI: Introduce pci_bus_addr_t

[Yinghai Lu <yinghai@kernel.org>]

David Ahern found commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows
to fit in upstream windows") broke booting on sparc/T5-8.

In the boot log, there is
  pci 0000:06:00.0: reg 0x184: can't handle BAR above 4GB (bus address
  0x110204000)
but that only could happen when dma_addr_t is 32-bit.

According to David Miller, all DMA occurs behind an IOMMU and these
IOMMUs only support 32-bit addressing, therefore dma_addr_t is
32-bit on sparc64.

Let's introduce pci_bus_addr_t instead of using dma_addr_t,
and pci_bus_addr_t will be 64-bit on 64-bit platform or X86_PAE.

Fixes: commit d63e2e1f3df9 ("sparc/PCI: Clip bridge windows to fit in upstream windows")
Fixes: commit 23b13bc76f35 ("PCI: Fail safely if we can't handle BARs larger than 4GB")
Link: http://lkml.kernel.org/r/CAE9FiQU1gJY1LYrxs+ma5LCTEEe4xmtjRG0aXJ9K_Tsu+m9Wuw@mail.gmail.com
Reported-by: David Ahern <david.ahern@oracle.com>
Tested-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: <stable@vger.kernel.org> #3.19
---
 drivers/pci/Kconfig |  4 ++++
 drivers/pci/bus.c   | 10 +++++-----
 drivers/pci/probe.c | 12 ++++++------
 include/linux/pci.h | 12 +++++++++---
 4 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 7a8f1c5..6a5a269 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -1,6 +1,10 @@
 #
 # PCI configuration
 #
+config PCI_BUS_ADDR_T_64BIT
+	def_bool y if (64BIT || X86_PAE)
+	depends on PCI
+
 config PCI_MSI
 	bool "Message Signaled Interrupts (MSI and MSI-X)"
 	depends on PCI
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 90fa3a7..6fbd3f2 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -92,11 +92,11 @@ void pci_bus_remove_resources(struct pci_bus *bus)
 }
 
 static struct pci_bus_region pci_32_bit = {0, 0xffffffffULL};
-#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
 static struct pci_bus_region pci_64_bit = {0,
-				(dma_addr_t) 0xffffffffffffffffULL};
-static struct pci_bus_region pci_high = {(dma_addr_t) 0x100000000ULL,
-				(dma_addr_t) 0xffffffffffffffffULL};
+				(pci_bus_addr_t) 0xffffffffffffffffULL};
+static struct pci_bus_region pci_high = {(pci_bus_addr_t) 0x100000000ULL,
+				(pci_bus_addr_t) 0xffffffffffffffffULL};
 #endif
 
 /*
@@ -200,7 +200,7 @@ int pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
 					  resource_size_t),
 		void *alignf_data)
 {
-#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
 	int rc;
 
 	if (res->flags & IORESOURCE_MEM_64) {
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 8d2f400..f71cb7c 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -253,8 +253,8 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 	}
 
 	if (res->flags & IORESOURCE_MEM_64) {
-		if ((sizeof(dma_addr_t) < 8 || sizeof(resource_size_t) < 8) &&
-		    sz64 > 0x100000000ULL) {
+		if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8)
+		    && sz64 > 0x100000000ULL) {
 			res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED;
 			res->start = 0;
 			res->end = 0;
@@ -263,7 +263,7 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
 			goto out;
 		}
 
-		if ((sizeof(dma_addr_t) < 8) && l) {
+		if ((sizeof(pci_bus_addr_t) < 8) && l) {
 			/* Above 32-bit boundary; try to reallocate */
 			res->flags |= IORESOURCE_UNSET;
 			res->start = 0;
@@ -398,7 +398,7 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
 	struct pci_dev *dev = child->self;
 	u16 mem_base_lo, mem_limit_lo;
 	u64 base64, limit64;
-	dma_addr_t base, limit;
+	pci_bus_addr_t base, limit;
 	struct pci_bus_region region;
 	struct resource *res;
 
@@ -425,8 +425,8 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
 		}
 	}
 
-	base = (dma_addr_t) base64;
-	limit = (dma_addr_t) limit64;
+	base = (pci_bus_addr_t) base64;
+	limit = (pci_bus_addr_t) limit64;
 
 	if (base != base64) {
 		dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 211e9da..6021bbe 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -573,9 +573,15 @@ int raw_pci_read(unsigned int domain, unsigned int bus, unsigned int devfn,
 int raw_pci_write(unsigned int domain, unsigned int bus, unsigned int devfn,
 		  int reg, int len, u32 val);
 
+#ifdef CONFIG_PCI_BUS_ADDR_T_64BIT
+typedef u64 pci_bus_addr_t;
+#else
+typedef u32 pci_bus_addr_t;
+#endif
+
 struct pci_bus_region {
-	dma_addr_t start;
-	dma_addr_t end;
+	pci_bus_addr_t start;
+	pci_bus_addr_t end;
 };
 
 struct pci_dynids {
@@ -1124,7 +1130,7 @@ int __must_check pci_bus_alloc_resource(struct pci_bus *bus,
 
 int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr);
 
-static inline dma_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
+static inline pci_bus_addr_t pci_bus_address(struct pci_dev *pdev, int bar)
 {
 	struct pci_bus_region region;
 
-- 
1.8.4.5