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authorIonela Voinescu <ionela.voinescu@imgtec.com>2014-09-24 17:05:33 +0100
committerPatrick Georgi <pgeorgi@google.com>2015-03-21 11:07:50 +0100
commitce22c023878d2b2e5963f379857ccec4815aeede (patch)
treeb047099359cc3695ac939803cd643c2f2de8afd3 /payloads/libpayload/include
parent51421633d534752c2d677a5255f9583ecdcd4a60 (diff)
libpayload: arch/mips: Add basic MIPS architecture support
Add the basic build infrastructure and architectural support required to build for targets using the MIPS architecture. This will require the addition of cache maintenance. BUG=chrome-os-partner:31438 TEST=tested on Pistachio FPGA with Depthcharge as payload; successfully executed payload. BRANCH=none Change-Id: I75cfd0536860b6d84b53a567940fe6668d9b2cbb Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: 758c8cb9a6846e6ca32be409ec5f7a888ac9c888 Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com> Original-Change-Id: I0b9af983bf5032335a519ce2510a0b3aca082edf Original-Reviewed-on: https://chromium-review.googlesource.com/219740 Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/8741 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Diffstat (limited to 'payloads/libpayload/include')
-rw-r--r--payloads/libpayload/include/mips/arch/byteorder.h43
-rw-r--r--payloads/libpayload/include/mips/arch/cache.h98
-rw-r--r--payloads/libpayload/include/mips/arch/cpu.h85
-rw-r--r--payloads/libpayload/include/mips/arch/exception.h90
-rw-r--r--payloads/libpayload/include/mips/arch/io.h67
-rw-r--r--payloads/libpayload/include/mips/arch/stdint.h95
-rw-r--r--payloads/libpayload/include/mips/arch/types.h76
-rw-r--r--payloads/libpayload/include/mips/arch/virtual.h31
-rw-r--r--payloads/libpayload/include/swab.h44
9 files changed, 629 insertions, 0 deletions
diff --git a/payloads/libpayload/include/mips/arch/byteorder.h b/payloads/libpayload/include/mips/arch/byteorder.h
new file mode 100644
index 0000000000..002451accc
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/byteorder.h
@@ -0,0 +1,43 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_BYTEORDER_H__
+#define __MIPS_ARCH_BYTEORDER_H__
+
+#include <stdint.h>
+#include <swab.h>
+
+#ifndef __ORDER_LITTLE_ENDIAN__
+#error "What endian are you!?"
+#endif
+
+#define cpu_to_le64(x) ((uint64_t)(x))
+#define le64_to_cpu(x) ((uint64_t)(x))
+#define cpu_to_le32(x) ((uint32_t)(x))
+#define le32_to_cpu(x) ((uint32_t)(x))
+#define cpu_to_le16(x) ((uint16_t)(x))
+#define le16_to_cpu(x) ((uint16_t)(x))
+#define cpu_to_be64(x) swab64(x)
+#define be64_to_cpu(x) swab64(x)
+#define cpu_to_be32(x) swab32((x))
+#define be32_to_cpu(x) swab32((x))
+#define cpu_to_be16(x) swab16((x))
+#define be16_to_cpu(x) swab16((x))
+
+#endif /* __MIPS_ARCH_BYTEORDER_H__ */
diff --git a/payloads/libpayload/include/mips/arch/cache.h b/payloads/libpayload/include/mips/arch/cache.h
new file mode 100644
index 0000000000..9485671e98
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/cache.h
@@ -0,0 +1,98 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_CACHE_H__
+#define __MIPS_ARCH_CACHE_H__
+
+
+#include <stddef.h>
+#include <stdint.h>
+
+
+/*
+ * Sync primitives
+ */
+
+/* data memory barrier */
+static inline void dmb(void)
+{
+ /* TODO */
+}
+
+/* data sync barrier */
+static inline void dsb(void)
+{
+ /* TODO */
+}
+
+/* instruction sync barrier */
+static inline void isb(void)
+{
+ /* TODO */
+}
+
+
+/*
+ * Cache maintenance API
+ */
+
+/* dcache clean and invalidate all */
+void dcache_clean_invalidate_all(void);
+
+/* dcache clean all */
+void dcache_clean_all(void);
+
+/* dcache invalidate all (on current level given by CCSELR) */
+void dcache_invalidate_all(void);
+
+/* returns number of bytes per cache line */
+unsigned int dcache_line_bytes(void);
+
+/* dcache and MMU disable */
+void dcache_mmu_disable(void);
+
+/* dcache and MMU enable */
+void dcache_mmu_enable(void);
+
+/* perform all icache/dcache maintenance needed after loading new code */
+void cache_sync_instructions(void);
+
+/* tlb invalidate all */
+void tlb_invalidate_all(void);
+
+/*
+ * Generalized setup/init functions
+ */
+
+/* mmu initialization (set page table address, set permissions, etc) */
+void mmu_init(void);
+
+enum dcache_policy {
+ DCACHE_OFF,
+ DCACHE_WRITEBACK,
+ DCACHE_WRITETHROUGH,
+};
+
+/* disable the mmu for a range. Primarily useful to lock out address 0. */
+void mmu_disable_range(unsigned long start_mb, unsigned long size_mb);
+/* mmu range configuration (set dcache policy) */
+void mmu_config_range(unsigned long start_mb, unsigned long size_mb,
+ enum dcache_policy policy);
+
+#endif /* __MIPS_ARCH_CACHE_H__ */
diff --git a/payloads/libpayload/include/mips/arch/cpu.h b/payloads/libpayload/include/mips/arch/cpu.h
new file mode 100644
index 0000000000..952ec7c528
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/cpu.h
@@ -0,0 +1,85 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#ifndef __MIPS_ARCH_CPU_H__
+#define __MIPS_ARCH_CPU_H__
+
+/*
+ * Reading at this address allows to identify the platform the code is running
+ * on
+ */
+#define IMG_PLATFORM_ID() (*((unsigned *)0xB8149060))
+#define IMG_PLATFORM_ID_SILICON 0xF00D0006
+
+#define CP0_COUNT 9
+#define CP0_COMPARE 11
+#define CP0_STATUS 12
+#define CP0_CAUSE 13
+#define CP0_WATCHLO 18
+#define CP0_WATCHHI 19
+
+/* coprocessor 0 enable */
+#define ST0_CU0 (1 << 28)
+#define C0_CAUSE_DC (1 << 27)
+
+/***************************************************************************
+ * The following section was copied from arch/mips/include/asm/mipsregs.h in
+ * the 3.14 kernel tree.
+ */
+
+/*
+ * Macros to access the system control coprocessor
+ */
+
+#define __read_32bit_c0_register(source, sel) \
+({ int __res; \
+ if (sel == 0) \
+ __asm__ __volatile__( \
+ "mfc0\t%0, " #source "\n\t" \
+ : "=r" (__res)); \
+ else \
+ __asm__ __volatile__( \
+ ".set\tmips32\n\t" \
+ "mfc0\t%0, " #source ", " #sel "\n\t" \
+ ".set\tmips0\n\t" \
+ : "=r" (__res)); \
+ __res; \
+})
+
+#define __write_32bit_c0_register(register, sel, value) \
+do { \
+ if (sel == 0) \
+ __asm__ __volatile__( \
+ "mtc0\t%z0, " #register "\n\t" \
+ : : "Jr" ((unsigned int)(value))); \
+ else \
+ __asm__ __volatile__( \
+ ".set\tmips32\n\t" \
+ "mtc0\t%z0, " #register ", " #sel "\n\t" \
+ ".set\tmips0" \
+ : : "Jr" ((unsigned int)(value))); \
+} while (0)
+
+/* Shortcuts to access various internal registers, keep adding as needed. */
+#define read_c0_count() __read_32bit_c0_register($9, 0)
+#define write_c0_count(val) __write_32bit_c0_register($9, 0, (val))
+
+#define read_c0_cause() __read_32bit_c0_register($13, 0)
+#define write_c0_cause(val) __write_32bit_c0_register($13, 0, (val))
+/***************************************************************************/
+
+#endif /* __MIPS_ARCH_CPU_H__ */
diff --git a/payloads/libpayload/include/mips/arch/exception.h b/payloads/libpayload/include/mips/arch/exception.h
new file mode 100644
index 0000000000..9557cb7049
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/exception.h
@@ -0,0 +1,90 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_EXCEPTION_H__
+#define __MIPS_ARCH_EXCEPTION_H__
+
+#include <stdint.h>
+
+void exception_init_asm(void);
+void exception_dispatch(void);
+
+struct exception_state_t {
+ struct {
+ /* Always 0: just to keep the series complete */
+ u32 zero;
+ /* Reserved for the assembler */
+ /* TODO: is this actually needed here? */
+ u32 at;
+ /* v0-v1: expression evaluation */
+ u32 v0;
+ u32 v1;
+ /* a0-a3: Arguments */
+ u32 a0;
+ u32 a1;
+ u32 a2;
+ u32 a3;
+ /* t0-t3: Temporary registers for expression evaluation */
+ u32 t0;
+ u32 t1;
+ u32 t2;
+ u32 t3;
+ u32 t4;
+ u32 t5;
+ u32 t6;
+ u32 t7;
+ /* s0-s7: Saved registers */
+ u32 s0;
+ u32 s1;
+ u32 s2;
+ u32 s3;
+ u32 s4;
+ u32 s5;
+ u32 s6;
+ u32 s7;
+ /* t8-t9: Temporary registers for expression evaluation */
+ u32 t8;
+ u32 t9;
+ /* k0-k1: reserved for SO kernel */
+ u32 k0;
+ u32 k1;
+ /* Global pointer */
+ u32 gp;
+ /* Stack pointer */
+ u32 sp;
+ /* Frame pointer */
+ u32 fp;
+ /* Return address */
+ u32 ra;
+ } regs;
+ u32 vector;
+} __attribute__((packed));
+
+extern struct exception_state_t *exception_state_ptr;
+extern u32 *exception_stack_end;
+
+enum {
+ EXC_CACHE_ERROR = 0,
+ EXC_TLB_REFILL_AND_ALL = 1,
+ EXC_INTERRUPT = 2,
+ EXC_EJTAG_DEBUG = 3,
+ EXC_COUNT
+};
+
+#endif /* __MIPS_ARCH_EXCEPTION_H__ */
diff --git a/payloads/libpayload/include/mips/arch/io.h b/payloads/libpayload/include/mips/arch/io.h
new file mode 100644
index 0000000000..d2d9338037
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/io.h
@@ -0,0 +1,67 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * Based on arch/armv7/include/arch/io.h:
+ * Copyright 2013 Google Inc.
+ * Copyright (C) 1996-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_IO_H__
+#define __MIPS_ARCH_IO_H__
+
+#include <arch/types.h>
+#include <arch/cache.h>
+#include <arch/byteorder.h>
+
+#define read8(a) (*(volatile uint8_t *) (a))
+#define read16(a) (*(volatile uint16_t *) (a))
+#define read32(a) (*(volatile uint32_t *) (a))
+
+#define write8(v, a) (*(volatile uint8_t *) (a) = (v))
+#define write16(v, a) (*(volatile uint16_t *) (a) = (v))
+#define write32(v, a) (*(volatile uint32_t *) (a) = (v))
+
+
+/*
+ * Clear and set bits in one shot. These macros can be used to clear and
+ * set multiple bits in a register using a single call. These macros can
+ * also be used to set a multiple-bit bit pattern using a mask, by
+ * specifying the mask in the 'clear' parameter and the new bit pattern
+ * in the 'set' parameter.
+ */
+
+#define out_arch(type, endian, a, v) write##type(cpu_to_##endian(v), a)
+#define in_arch(type, endian, a) endian##_to_cpu(read##type(a))
+
+#define readb(a) read8(a)
+#define readw(a) read16(a)
+#define readl(a) read32(a)
+
+#define inb(a) read8(a)
+#define inw(a) read16(a)
+#define inl(a) read32(a)
+
+#define writeb(v, a) write8(v, a)
+#define writew(v, a) write16(v, a)
+#define writel(v, a) write32(v, a)
+
+#define outb(v, a) write8(v, a)
+#define outw(v, a) write16(v, a)
+#define outl(v, a) write32(v, a)
+
+#endif /* __MIPS_ARCH_IO_H__ */
diff --git a/payloads/libpayload/include/mips/arch/stdint.h b/payloads/libpayload/include/mips/arch/stdint.h
new file mode 100644
index 0000000000..c182530862
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/stdint.h
@@ -0,0 +1,95 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Based on src/arch/armv7/include/stdint.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_STDINT_H__
+#define __MIPS_STDINT_H__
+
+#if defined(__GNUC__)
+#define __HAVE_LONG_LONG__ 1
+#else
+#define __HAVE_LONG_LONG__ 0
+#endif
+
+/* Exact integral types */
+typedef unsigned char uint8_t;
+typedef signed char int8_t;
+
+typedef unsigned short uint16_t;
+typedef signed short int16_t;
+
+typedef unsigned int uint32_t;
+typedef signed int int32_t;
+
+#if __HAVE_LONG_LONG__
+typedef unsigned long long uint64_t;
+typedef signed long long int64_t;
+#endif
+
+/* Small types */
+typedef unsigned char uint_least8_t;
+typedef signed char int_least8_t;
+
+typedef unsigned short uint_least16_t;
+typedef signed short int_least16_t;
+
+typedef unsigned int uint_least32_t;
+typedef signed int int_least32_t;
+
+#if __HAVE_LONG_LONG__
+typedef unsigned long long uint_least64_t;
+typedef signed long long int_least64_t;
+#endif
+
+/* Fast Types */
+typedef unsigned char uint_fast8_t;
+typedef signed char int_fast8_t;
+
+typedef unsigned int uint_fast16_t;
+typedef signed int int_fast16_t;
+
+typedef unsigned int uint_fast32_t;
+typedef signed int int_fast32_t;
+
+#if __HAVE_LONG_LONG__
+typedef unsigned long long uint_fast64_t;
+typedef signed long long int_fast64_t;
+#endif
+
+/* Largest integral types */
+#if __HAVE_LONG_LONG__
+typedef long long int intmax_t;
+typedef unsigned long long uintmax_t;
+#else
+typedef long int intmax_t;
+typedef unsigned long int uintmax_t;
+#endif
+
+typedef uint8_t u8;
+typedef uint16_t u16;
+typedef uint32_t u32;
+#if __HAVE_LONG_LONG__
+typedef uint64_t u64;
+#endif
+typedef int8_t s8;
+typedef int16_t s16;
+typedef int32_t s32;
+
+#undef __HAVE_LONG_LONG__
+
+#endif /* __MIPS_STDINT_H__ */
diff --git a/payloads/libpayload/include/mips/arch/types.h b/payloads/libpayload/include/mips/arch/types.h
new file mode 100644
index 0000000000..151817e679
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/types.h
@@ -0,0 +1,76 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * Based on src/arch/armv7/include/arch/types.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_TYPES_H
+#define __MIPS_ARCH_TYPES_H
+
+#include <arch/stdint.h>
+
+typedef unsigned short umode_t;
+
+/*
+ * __xx is ok: it doesn't pollute the POSIX namespace. Use these in the
+ * header files exported to user space
+ */
+
+typedef __signed__ char __s8;
+typedef unsigned char __u8;
+
+typedef __signed__ short __s16;
+typedef unsigned short __u16;
+
+typedef __signed__ int __s32;
+typedef unsigned int __u32;
+
+#if defined(__GNUC__)
+__extension__ typedef __signed__ long long __s64;
+__extension__ typedef unsigned long long __u64;
+#endif
+
+typedef signed char s8;
+typedef unsigned char u8;
+
+typedef signed short s16;
+typedef unsigned short u16;
+
+typedef signed int s32;
+typedef unsigned int u32;
+
+typedef signed long long s64;
+typedef unsigned long long u64;
+
+#define BITS_PER_LONG 32
+
+/* Dma addresses are 32-bits wide. */
+
+typedef u32 dma_addr_t;
+
+typedef unsigned long phys_addr_t;
+typedef unsigned long phys_size_t;
+
+typedef long time_t;
+typedef long suseconds_t;
+
+#ifndef NULL
+#define NULL ((void *)0)
+#endif
+
+#endif /* __MIPS_ARCH_TYPES_H */
diff --git a/payloads/libpayload/include/mips/arch/virtual.h b/payloads/libpayload/include/mips/arch/virtual.h
new file mode 100644
index 0000000000..70aea20b9c
--- /dev/null
+++ b/payloads/libpayload/include/mips/arch/virtual.h
@@ -0,0 +1,31 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (C) 2014 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __MIPS_ARCH_VIRTUAL_H
+#define __MIPS_ARCH_VIRTUAL_H
+
+extern unsigned long virtual_offset;
+
+#define virt_to_phys(virt) ((unsigned long) (virt) + virtual_offset)
+#define phys_to_virt(phys) ((void *) ((unsigned long) (phys) - virtual_offset))
+
+#define virt_to_bus(addr) virt_to_phys(addr)
+#define bus_to_virt(addr) phys_to_virt(addr)
+
+#endif
diff --git a/payloads/libpayload/include/swab.h b/payloads/libpayload/include/swab.h
new file mode 100644
index 0000000000..2198077ad2
--- /dev/null
+++ b/payloads/libpayload/include/swab.h
@@ -0,0 +1,44 @@
+#ifndef _SWAB_H
+#define _SWAB_H
+
+/*
+ * linux/byteorder/swab.h
+ * Byte-swapping, independently from CPU endianness
+ * swabXX[ps]?(foo)
+ *
+ * Francois-Rene Rideau <fare@tunes.org> 19971205
+ * separated swab functions from cpu_to_XX,
+ * to clean up support for bizarre-endian architectures.
+ *
+ * See asm-i386/byteorder.h and suches for examples of how to provide
+ * architecture-dependent optimized versions
+ *
+ */
+
+/* casts are necessary for constants, because we never know for sure
+ * how U/UL/ULL map to __u16, __u32, __u64. At least not in a portable way.
+ */
+#define swab16(x) \
+ ((unsigned short)( \
+ (((unsigned short)(x) & (unsigned short)0x00ffU) << 8) | \
+ (((unsigned short)(x) & (unsigned short)0xff00U) >> 8)))
+
+#define swab32(x) \
+ ((unsigned int)( \
+ (((unsigned int)(x) & (unsigned int)0x000000ffUL) << 24) | \
+ (((unsigned int)(x) & (unsigned int)0x0000ff00UL) << 8) | \
+ (((unsigned int)(x) & (unsigned int)0x00ff0000UL) >> 8) | \
+ (((unsigned int)(x) & (unsigned int)0xff000000UL) >> 24)))
+
+#define swab64(x) \
+ ((uint64_t)( \
+ (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) | \
+ (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
+ (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
+ (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) << 8) | \
+ (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >> 8) | \
+ (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
+ (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
+ (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
+
+#endif /* _SWAB_H */