1 # SPDX-License-Identifier: GPL-2.0-only
4 menu "Intel IXP4xx Implementation Options"
6 comment "IXP4xx Platforms"
10 prompt "Device Tree IXP4xx boards"
12 select ARM_APPENDED_DTB # Old Redboot bootloaders deployed
18 Say 'Y' here to support Device Tree-based IXP4xx platforms.
20 config MACH_GATEWAY7001
22 depends on IXP4XX_PCI_LEGACY
24 Say 'Y' here if you want your kernel to support Gateway's
25 7001 Access Point. For more information on this platform,
26 see http://openwrt.org
28 config MACH_GORAMO_MLR
29 bool "GORAMO Multi Link Router"
31 Say 'Y' here if you want your kernel to support GORAMO
37 Say 'Y' here if you want your kernel to support the Motorola
38 PrPCM1100 Processor Mezanine Module. For more information on
39 this platform, see <file:Documentation/arm/ixp4xx.rst>.
42 # Certain registers and IRQs are only enabled if supporting IXP465 CPUs
46 depends on MACH_IXDP465
51 depends on MACH_KIXRP435
54 comment "IXP4xx Options"
56 config IXP4XX_PCI_LEGACY
57 bool "IXP4xx legacy PCI driver support"
60 Selects legacy PCI driver.
61 Not recommended for new development.
63 config IXP4XX_INDIRECT_PCI
64 bool "Use indirect PCI memory access"
65 depends on IXP4XX_PCI_LEGACY
67 IXP4xx provides two methods of accessing PCI memory space:
69 1) A direct mapped window from 0x48000000 to 0x4BFFFFFF (64MB).
70 To access PCI via this space, we simply ioremap() the BAR
71 into the kernel and we can use the standard read[bwl]/write[bwl]
72 macros. This is the preferred method due to speed but it
73 limits the system to just 64MB of PCI memory. This can be
74 problematic if using video cards and other memory-heavy devices.
76 2) If > 64MB of memory space is required, the IXP4xx can be
77 configured to use indirect registers to access the whole PCI
78 memory space. This currently allows for up to 1 GB (0x10000000
79 to 0x4FFFFFFF) of memory on the bus. The disadvantage of this
80 is that every PCI access requires three local register accesses
81 plus a spinlock, but in some cases the performance hit is
82 acceptable. In addition, you cannot mmap() PCI devices in this
83 case due to the indirect nature of the PCI window.
85 By default, the direct method is used. Choose this option if you
86 need to use the indirect method instead. If you don't know
87 what you need, leave this option unselected.