summaryrefslogtreecommitdiff
path: root/include/asm-mips/mach-generic
diff options
context:
space:
mode:
authorAtsushi Nemoto <anemo@mba.ocn.ne.jp>2006-02-16 16:36:24 (GMT)
committerRalf Baechle <ralf@linux-mips.org>2006-03-21 13:27:45 (GMT)
commita8433137ea9143bb3a2bc18a3407b5a130fdb868 (patch)
treeff40223bf542173015c070a988a4f3b0554f89ea /include/asm-mips/mach-generic
parentc1449c8fa40859eb269025a7db85b34115205f5b (diff)
downloadlinux-a8433137ea9143bb3a2bc18a3407b5a130fdb868.tar.xz
[MIPS] Make I/O helpers more customizable
1. Move ioswab*() and __mem_ioswab*() to mangle-port.h. This gets rid of CONFIG_SGI_IP22 from include/asm-mips/io.h. 2. Pass a virtual address to *ioswab*(). Then we can provide mach-specific *ioswab*() and can do every evil thing based on its argument. It could be useful on machines which have regions with different endian conversion scheme. 3. Call __swizzle_addr*() _after_ adding mips_io_port_base. This unifies the meaning of the argument of __swizzle_addr*() (always virtual address). Then mach-specific __swizzle_addr*() can do every evil thing based on the argument. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'include/asm-mips/mach-generic')
-rw-r--r--include/asm-mips/mach-generic/mangle-port.h36
1 files changed, 36 insertions, 0 deletions
diff --git a/include/asm-mips/mach-generic/mangle-port.h b/include/asm-mips/mach-generic/mangle-port.h
index 4a98d83..6e1b0c0 100644
--- a/include/asm-mips/mach-generic/mangle-port.h
+++ b/include/asm-mips/mach-generic/mangle-port.h
@@ -13,4 +13,40 @@
#define __swizzle_addr_l(port) (port)
#define __swizzle_addr_q(port) (port)
+/*
+ * Sane hardware offers swapping of PCI/ISA I/O space accesses in hardware;
+ * less sane hardware forces software to fiddle with this...
+ *
+ * Regardless, if the host bus endianness mismatches that of PCI/ISA, then
+ * you can't have the numerical value of data and byte addresses within
+ * multibyte quantities both preserved at the same time. Hence two
+ * variations of functions: non-prefixed ones that preserve the value
+ * and prefixed ones that preserve byte addresses. The latters are
+ * typically used for moving raw data between a peripheral and memory (cf.
+ * string I/O functions), hence the "__mem_" prefix.
+ */
+#if defined(CONFIG_SWAP_IO_SPACE)
+
+# define ioswabb(a,x) (x)
+# define __mem_ioswabb(a,x) (x)
+# define ioswabw(a,x) le16_to_cpu(x)
+# define __mem_ioswabw(a,x) (x)
+# define ioswabl(a,x) le32_to_cpu(x)
+# define __mem_ioswabl(a,x) (x)
+# define ioswabq(a,x) le64_to_cpu(x)
+# define __mem_ioswabq(a,x) (x)
+
+#else
+
+# define ioswabb(a,x) (x)
+# define __mem_ioswabb(a,x) (x)
+# define ioswabw(a,x) (x)
+# define __mem_ioswabw(a,x) cpu_to_le16(x)
+# define ioswabl(a,x) (x)
+# define __mem_ioswabl(a,x) cpu_to_le32(x)
+# define ioswabq(a,x) (x)
+# define __mem_ioswabq(a,x) cpu_to_le32(x)
+
+#endif
+
#endif /* __ASM_MACH_GENERIC_MANGLE_PORT_H */