diff options
Diffstat (limited to 'target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch')
| -rw-r--r-- | target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch | 32 |
1 files changed, 13 insertions, 19 deletions
diff --git a/target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch b/target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch index 83e2a4964f..f5d0a58c6c 100644 --- a/target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch +++ b/target/linux/ixp4xx/patches-2.6.35/050-disable_dmabounce.patch @@ -1,8 +1,8 @@ --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig -@@ -417,7 +417,6 @@ config ARCH_IXP4XX +@@ -435,7 +435,6 @@ config ARCH_IXP4XX + select CPU_XSCALE select GENERIC_GPIO - select GENERIC_TIME select GENERIC_CLOCKEVENTS - select DMABOUNCE if PCI help @@ -10,26 +10,24 @@ --- a/arch/arm/mach-ixp4xx/Kconfig +++ b/arch/arm/mach-ixp4xx/Kconfig -@@ -199,6 +199,45 @@ config IXP4XX_INDIRECT_PCI +@@ -199,6 +199,43 @@ config IXP4XX_INDIRECT_PCI need to use the indirect method instead. If you don't know what you need, leave this option unselected. +config IXP4XX_LEGACY_DMABOUNCE -+ bool "legacy PCI DMA bounce support" ++ bool "Legacy PCI DMA bounce support" + depends on PCI + default n + select DMABOUNCE + help + The IXP4xx is limited to a 64MB window for PCI DMA, which -+ requires that PCI accesses above 64MB are bounced via buffers -+ below 64MB. Furthermore the IXP4xx has an erratum where PCI -+ read prefetches just below the 64MB limit can trigger lockups. ++ requires that PCI accesses >= 64MB are bounced via buffers ++ below 64MB. + -+ The kernel has traditionally handled these two issue by using -+ ARM specific DMA bounce support code for all accesses >= 64MB. ++ The kernel has traditionally handled this issue by using ARM ++ specific DMA bounce support code for all accesses >= 64MB. + That code causes problems of its own, so it is desirable to -+ disable it. As the kernel now has a workaround for the PCI read -+ prefetch erratum, it no longer requires the ARM bounce code. ++ disable it. + + Enabling this option makes IXP4xx continue to use the problematic + ARM DMA bounce code. Disabling this option makes IXP4xx use the @@ -58,7 +56,7 @@ help --- a/arch/arm/mach-ixp4xx/common-pci.c +++ b/arch/arm/mach-ixp4xx/common-pci.c -@@ -321,27 +321,38 @@ static int abort_handler(unsigned long a +@@ -321,27 +321,33 @@ static int abort_handler(unsigned long a */ static int ixp4xx_pci_platform_notify(struct device *dev) { @@ -88,12 +86,8 @@ +#ifdef CONFIG_DMABOUNCE int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size) { -+ /* Note that this returns true for the last page below 64M due to -+ * IXP4xx erratum 15 (SCR 1289), which states that PCI prefetches -+ * can cross the boundary between valid memory and a reserved region -+ * causing AHB bus errors and a lock-up. -+ */ - return (dev->bus == &pci_bus_type ) && ((dma_addr + size) >= SZ_64M); +- return (dev->bus == &pci_bus_type ) && ((dma_addr + size) >= SZ_64M); ++ return (dev->bus == &pci_bus_type ) && ((dma_addr + size) > SZ_64M); } +#endif @@ -101,7 +95,7 @@ /* * Only first 64MB of memory can be accessed via PCI. * We use GFP_DMA to allocate safe buffers to do map/unmap. -@@ -364,6 +375,7 @@ void __init ixp4xx_adjust_zones(int node +@@ -364,6 +370,7 @@ void __init ixp4xx_adjust_zones(int node zhole_size[1] = zhole_size[0]; zhole_size[0] = 0; } |