From 84613387cb60bc760a4588822cd61fb88e1d7fad Mon Sep 17 00:00:00 2001 From: Alessandro Zummo Date: Sun, 6 Nov 2005 14:34:12 +0000 Subject: [ARM] 3089/1: ixp4xx AHB/PCI endianness fix MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch from Alessandro Zummo This patch fixes AHB/PCI endianness problems when the processor is in little-endian mode. The patch configures the CSR register closely following the directives in [1], paragraph 4.1, page 19. According to the considerations in [1], page 11, while the AHB bus supports both endian modes, on the IXP4XX it always uses big-endian. The PCI bus is connected to the South AHB. A wrong setting in the CSR register will thus cause a malfunctional PCI bus. A schematic diagram of the bus interconnections on the IXP4XX can be found in [1], page 18. The patch has been verified to work on the NSLU2 in both LE and BE modes. The author is Peter Korsgaard. [1] Intel® IXP4XX Product Line of Network Processors and IXC1100 Control Plane Processor: Understanding Big Endian and Little Endian Modes http://www.intel.com/design/network/applnots/25423701.pdf Signed-off-by: Alessandro Zummo Signed-off-by: Deepak Saxena Signed-off-by: Russell King --- arch/arm/mach-ixp4xx/common-pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm/mach-ixp4xx/common-pci.c b/arch/arm/mach-ixp4xx/common-pci.c index 2b544363c078..9795da270e3a 100644 --- a/arch/arm/mach-ixp4xx/common-pci.c +++ b/arch/arm/mach-ixp4xx/common-pci.c @@ -427,7 +427,7 @@ void __init ixp4xx_pci_preinit(void) #ifdef __ARMEB__ *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS; #else - *PCI_CSR = PCI_CSR_IC; + *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE; #endif pr_debug("DONE\n"); -- cgit v1.2.3-58-ga151