--- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -435,7 +435,6 @@ config ARCH_IXP4XX select CPU_XSCALE select GENERIC_GPIO select GENERIC_CLOCKEVENTS - select DMABOUNCE if PCI help Support for Intel's IXP4XX (XScale) family of processors. --- a/arch/arm/mach-ixp4xx/Kconfig +++ b/arch/arm/mach-ixp4xx/Kconfig @@ -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" + depends on PCI + default n + select DMABOUNCE + help + The IXP4xx is limited to a 64MB window for PCI DMA, which + requires that PCI accesses >= 64MB are bounced via buffers + below 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. + + Enabling this option makes IXP4xx continue to use the problematic + ARM DMA bounce code. Disabling this option makes IXP4xx use the + kernel's generic bounce code. + + Say 'N'. + +config IXP4XX_ZONE_DMA + bool "Support > 64MB RAM" + depends on !IXP4XX_LEGACY_DMABOUNCE + default y + select ZONE_DMA + 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. + + Disabling this option allows you to omit the support code for + DMA-able memory allocations and DMA bouncing, but the kernel + will then not work properly if more than 64MB of RAM is present. + + Say 'Y' unless your platform is limited to <= 64MB of RAM. + config IXP4XX_QMGR tristate "IXP4xx Queue Manager support" help --- a/arch/arm/mach-ixp4xx/common-pci.c +++ b/arch/arm/mach-ixp4xx/common-pci.c @@ -321,27 +321,33 @@ static int abort_handler(unsigned long a */ static int ixp4xx_pci_platform_notify(struct device *dev) { - if(dev->bus == &pci_bus_type) { - *dev->dma_mask = SZ_64M - 1; + if (dev->bus == &pci_bus_type) { + *dev->dma_mask = SZ_64M - 1; dev->coherent_dma_mask = SZ_64M - 1; +#ifdef CONFIG_DMABOUNCE dmabounce_register_dev(dev, 2048, 4096); +#endif } return 0; } static int ixp4xx_pci_platform_notify_remove(struct device *dev) { - if(dev->bus == &pci_bus_type) { +#ifdef CONFIG_DMABOUNCE + if (dev->bus == &pci_bus_type) dmabounce_unregister_dev(dev); - } +#endif return 0; } -int dma_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size) +#ifdef CONFIG_DMABOUNCE +int dma_needs_bounce_2(struct device *dev, dma_addr_t dma_addr, size_t size) { - return (dev->bus == &pci_bus_type ) && ((dma_addr + size) >= SZ_64M); + return (dev->bus == &pci_bus_type ) && ((dma_addr + size) > SZ_64M); } +#endif +#ifdef CONFIG_ZONE_DMA /* * Only first 64MB of memory can be accessed via PCI. * We use GFP_DMA to allocate safe buffers to do map/unmap. @@ -364,6 +370,7 @@ void __init ixp4xx_adjust_zones(unsigned zhole_size[1] = zhole_size[0]; zhole_size[0] = 0; } +#endif void __init ixp4xx_pci_preinit(void) { --- a/arch/arm/mach-ixp4xx/include/mach/memory.h +++ b/arch/arm/mach-ixp4xx/include/mach/memory.h @@ -16,10 +16,12 @@ #if !defined(__ASSEMBLY__) && defined(CONFIG_PCI) +#ifdef CONFIG_ZONE_DMA void ixp4xx_adjust_zones(unsigned long *size, unsigned long *holes); #define arch_adjust_zones(size, holes) \ ixp4xx_adjust_zones(size, holes) +#endif #define ISA_DMA_THRESHOLD (SZ_64M - 1) #define MAX_DMA_ADDRESS (PAGE_OFFSET + SZ_64M) --- a/arch/arm/common/dmabounce.c +++ b/arch/arm/common/dmabounce.c @@ -30,6 +30,7 @@ #include #include #include +#include #include #include @@ -248,8 +249,15 @@ static inline dma_addr_t map_single(stru needs_bounce = (dma_addr | (dma_addr + size - 1)) & ~mask; } - if (device_info && (needs_bounce || dma_needs_bounce(dev, dma_addr, size))) { +#ifdef CONFIG_DMABOUNCE +int dma_needs_bounce_2(struct device *dev, dma_addr_t dma_addr, size_t size) +{ + return (dev->bus == &pci_bus_type ) && ((dma_addr + size) > SZ_64M); +} + + if (device_info && (needs_bounce || dma_needs_bounce_2(dev, dma_addr, size))) { struct safe_buffer *buf; +#endif buf = alloc_safe_buffer(device_info, ptr, size, dir); if (buf == 0) {