[PATCH] arm: versatile: fix and enable PCI I/O space

Rob Herring robherring2 at gmail.com
Mon Jun 11 10:03:58 EDT 2012


From: Arnd Bergmann <arnd at arndb.de>

With commit 4d5fc58dbe34b (ARM: remove bunch of now unused
mach/io.h files), the I/O space setup was completely broken on
versatile. This patch fixes that and prepares for further
I/O space clean-up.

I/O space handling on the versatile platform is currently
broken in multiple ways. Most importantly, the ports do
not get mapped into the virtual address space at all.

Also, there is some amount of confusion between PCI I/O
space and other statically mapped MMIO registers in the
platform code:

* The __io_address() macro that is used to access the
  platform register maps to the same __io macro that gets
  used for I/O space.

* The IO_SPACE_LIMIT is set to a value that is much larger
  than the total available space.

* The I/O resource of the PCI bus is set to the physical
  address of the mapping, which is way outside of the
  actual I/O space limit as well as the address range that
  gets decoded by traditional PCI cards.

* No attempt is made to stay outside of the ISA port range
  that some device drivers try access.

* No resource gets requested as a child of ioport_resource,
  but an IORESOURCE_IO type mapping gets requested
  as a child of iomem_resource.

This patch attempts to correct all of the above. This makes
it possible to use virtio-pci based virtual devices as well
as actual PCI cards including those with legacy ISA port
ranges like VGA.

Some of the issues seem to be duplicated on other platforms.

Signed-off-by: Arnd Bergmann <arnd at arndb.de>
[rob: update to 3.5-rc2 and io.h cleanup related changes]
Signed-off-by: Rob Herring <rob.herring at calxeda.com>
---
Arnd, Olof,

This should be applied for 3.5. There is a more simple fix to just
restore IO_RESOURCE_LIMIT to 0xffffffff, but I think that moves in
the wrong direction. This patch is needed to unify the I/O space
mapping.

Rob

 arch/arm/Kconfig                                |    1 +
 arch/arm/mach-versatile/core.c                  |   19 +++-------------
 arch/arm/mach-versatile/include/mach/hardware.h |    3 ++-
 arch/arm/mach-versatile/include/mach/io.h       |   27 +++++++++++++++++++++++
 arch/arm/mach-versatile/pci.c                   |   18 +++++++++++++--
 5 files changed, 49 insertions(+), 19 deletions(-)
 create mode 100644 arch/arm/mach-versatile/include/mach/io.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 84449dd..b1b2752 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -293,6 +293,7 @@ config ARCH_VERSATILE
 	select ICST
 	select GENERIC_CLOCKEVENTS
 	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select NEED_MACH_IO_H if PCI
 	select PLAT_VERSATILE
 	select PLAT_VERSATILE_CLCD
 	select PLAT_VERSATILE_FPGA_IRQ
diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c
index cf4687e..cd8ea35 100644
--- a/arch/arm/mach-versatile/core.c
+++ b/arch/arm/mach-versatile/core.c
@@ -169,26 +169,13 @@ static struct map_desc versatile_io_desc[] __initdata = {
 		.pfn		= __phys_to_pfn(VERSATILE_PCI_CFG_BASE),
 		.length		= VERSATILE_PCI_CFG_BASE_SIZE,
 		.type		= MT_DEVICE
-	},
-#if 0
- 	{
-		.virtual	=  VERSATILE_PCI_VIRT_MEM_BASE0,
-		.pfn		= __phys_to_pfn(VERSATILE_PCI_MEM_BASE0),
-		.length		= SZ_16M,
-		.type		= MT_DEVICE
 	}, {
-		.virtual	=  VERSATILE_PCI_VIRT_MEM_BASE1,
-		.pfn		= __phys_to_pfn(VERSATILE_PCI_MEM_BASE1),
-		.length		= SZ_16M,
-		.type		= MT_DEVICE
-	}, {
-		.virtual	=  VERSATILE_PCI_VIRT_MEM_BASE2,
-		.pfn		= __phys_to_pfn(VERSATILE_PCI_MEM_BASE2),
-		.length		= SZ_16M,
+		.virtual	=  (unsigned long)VERSATILE_PCI_VIRT_MEM_BASE0,
+		.pfn		= __phys_to_pfn(VERSATILE_PCI_MEM_BASE0),
+		.length		= IO_SPACE_LIMIT,
 		.type		= MT_DEVICE
 	},
 #endif
-#endif
 };
 
 void __init versatile_map_io(void)
diff --git a/arch/arm/mach-versatile/include/mach/hardware.h b/arch/arm/mach-versatile/include/mach/hardware.h
index 4d4973d..408e58d 100644
--- a/arch/arm/mach-versatile/include/mach/hardware.h
+++ b/arch/arm/mach-versatile/include/mach/hardware.h
@@ -29,8 +29,9 @@
  */
 #define VERSATILE_PCI_VIRT_BASE		(void __iomem *)0xe8000000ul
 #define VERSATILE_PCI_CFG_VIRT_BASE	(void __iomem *)0xe9000000ul
+#define VERSATILE_PCI_VIRT_MEM_BASE0	(void __iomem *)PCIO_BASE
 
-/* macro to get at IO space when running virtually */
+/* macro to get at MMIO space when running virtually */
 #define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
 
 #define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))
diff --git a/arch/arm/mach-versatile/include/mach/io.h b/arch/arm/mach-versatile/include/mach/io.h
new file mode 100644
index 0000000..90f729f
--- /dev/null
+++ b/arch/arm/mach-versatile/include/mach/io.h
@@ -0,0 +1,27 @@
+/*
+ *  arch/arm/mach-versatile/include/mach/io.h
+ *
+ *  Copyright (C) 2003 ARM Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#ifndef __ASM_ARM_ARCH_IO_H
+#define __ASM_ARM_ARCH_IO_H
+
+#define PCIO_BASE	0xeb000000ul
+ 
+#define __io(a)		((a) + PCIO_BASE)
+
+#endif
diff --git a/arch/arm/mach-versatile/pci.c b/arch/arm/mach-versatile/pci.c
index 15c6a00..bec933b 100644
--- a/arch/arm/mach-versatile/pci.c
+++ b/arch/arm/mach-versatile/pci.c
@@ -169,11 +169,18 @@ static struct pci_ops pci_versatile_ops = {
 	.write	= versatile_write_config,
 };
 
+static struct resource io_port = {
+	.name	= "PCI",
+	.start	= 0,
+	.end	= IO_SPACE_LIMIT,
+	.flags	= IORESOURCE_IO,
+};
+
 static struct resource io_mem = {
 	.name	= "PCI I/O space",
 	.start	= VERSATILE_PCI_MEM_BASE0,
 	.end	= VERSATILE_PCI_MEM_BASE0+VERSATILE_PCI_MEM_BASE0_SIZE-1,
-	.flags	= IORESOURCE_IO,
+	.flags	= IORESOURCE_MEM,
 };
 
 static struct resource non_mem = {
@@ -200,6 +207,12 @@ static int __init pci_versatile_setup_resources(struct pci_sys_data *sys)
 		       "memory region (%d)\n", ret);
 		goto out;
 	}
+	ret = request_resource(&ioport_resource, &io_port);
+	if (ret) {
+		printk(KERN_ERR "PCI: unable to allocate I/O "
+		       "port region (%d)\n", ret);
+		goto out;
+	}
 	ret = request_resource(&iomem_resource, &non_mem);
 	if (ret) {
 		printk(KERN_ERR "PCI: unable to allocate non-prefetchable "
@@ -218,7 +231,7 @@ static int __init pci_versatile_setup_resources(struct pci_sys_data *sys)
 	 * the mem resource for this bus
 	 * the prefetch mem resource for this bus
 	 */
-	pci_add_resource_offset(&sys->resources, &io_mem, sys->io_offset);
+	pci_add_resource_offset(&sys->resources, &io_port, sys->io_offset);
 	pci_add_resource_offset(&sys->resources, &non_mem, sys->mem_offset);
 	pci_add_resource_offset(&sys->resources, &pre_mem, sys->mem_offset);
 
@@ -249,6 +262,7 @@ int __init pci_versatile_setup(int nr, struct pci_sys_data *sys)
 
 	if (nr == 0) {
 		sys->mem_offset = 0;
+		sys->io_offset = 0;
 		ret = pci_versatile_setup_resources(sys);
 		if (ret < 0) {
 			printk("pci_versatile_setup: resources... oops?\n");
-- 
1.7.9.5




More information about the linux-arm-kernel mailing list