Author: tijl
Date: Mon Oct 22 20:55:35 2018
New Revision: 339618
URL: https://svnweb.freebsd.org/changeset/base/339618
Log:
Define linuxkpi readq for 64-bit architectures. It is used by drm-kmod.
Currently the compiler picks up the definition in machine/cpufunc.h.
Add compiler memory barriers to read* and write*. The Linux x86
implementation of these functions uses inline asm with "memory" clobber.
The Linux x86 implementation of read_relaxed* and write_relaxed* uses the
same inline asm without "memory" clobber.
Implement ioread* and iowrite* in terms of read* and write* so they also
have memory barriers.
Qualify the addr parameter in write* as volatile.
Like Linux, define macros with the same name as the inline functions.
Only define 64-bit versions on 64-bit architectures because generally
32-bit architectures can't do atomic 64-bit loads and stores.
Regroup the functions a bit and add brief comments explaining what they do:
- __raw_read*, __raw_write*: atomic, no barriers, no byte swapping
- read_relaxed*, write_relaxed*: atomic, no barriers, little-endian
- read*, write*: atomic, with barriers, little-endian
Add a comment that says our implementation of ioread* and iowrite*
only handles MMIO and does not support port IO.
Reviewed by: hselasky
MFC after: 3 days
Modified:
head/sys/compat/linuxkpi/common/include/linux/io.h
Modified: head/sys/compat/linuxkpi/common/include/linux/io.h
==============================================================================
--- head/sys/compat/linuxkpi/common/include/linux/io.h Mon Oct 22 20:22:33
2018 (r339617)
+++ head/sys/compat/linuxkpi/common/include/linux/io.h Mon Oct 22 20:55:35
2018 (r339618)
@@ -38,153 +38,309 @@
#include <linux/compiler.h>
#include <linux/types.h>
+/*
+ * XXX This is all x86 specific. It should be bus space access.
+ */
+
+/* Access MMIO registers atomically without barriers and byte swapping. */
+
+static inline uint8_t
+__raw_readb(const volatile void *addr)
+{
+ return (*(const volatile uint8_t *)addr);
+}
+#define __raw_readb(addr) __raw_readb(addr)
+
+static inline void
+__raw_writeb(uint8_t v, volatile void *addr)
+{
+ *(volatile uint8_t *)addr = v;
+}
+#define __raw_writeb(v, addr) __raw_writeb(v, addr)
+
+static inline uint16_t
+__raw_readw(const volatile void *addr)
+{
+ return (*(const volatile uint16_t *)addr);
+}
+#define __raw_readw(addr) __raw_readw(addr)
+
+static inline void
+__raw_writew(uint16_t v, volatile void *addr)
+{
+ *(volatile uint16_t *)addr = v;
+}
+#define __raw_writew(v, addr) __raw_writew(v, addr)
+
static inline uint32_t
__raw_readl(const volatile void *addr)
{
- return *(const volatile uint32_t *)addr;
+ return (*(const volatile uint32_t *)addr);
}
+#define __raw_readl(addr) __raw_readl(addr)
static inline void
-__raw_writel(uint32_t b, volatile void *addr)
+__raw_writel(uint32_t v, volatile void *addr)
{
- *(volatile uint32_t *)addr = b;
+ *(volatile uint32_t *)addr = v;
}
+#define __raw_writel(v, addr) __raw_writel(v, addr)
+#ifdef __LP64__
static inline uint64_t
__raw_readq(const volatile void *addr)
{
- return *(const volatile uint64_t *)addr;
+ return (*(const volatile uint64_t *)addr);
}
+#define __raw_readq(addr) __raw_readq(addr)
static inline void
-__raw_writeq(uint64_t b, volatile void *addr)
+__raw_writeq(uint64_t v, volatile void *addr)
{
- *(volatile uint64_t *)addr = b;
+ *(volatile uint64_t *)addr = v;
}
+#define __raw_writeq(v, addr) __raw_writeq(v, addr)
+#endif
-/*
- * XXX This is all x86 specific. It should be bus space access.
- */
#define mmiowb() barrier()
-#undef writel
+/* Access little-endian MMIO registers atomically with memory barriers. */
+
+#undef readb
+static inline uint8_t
+readb(const volatile void *addr)
+{
+ uint8_t v;
+
+ __compiler_membar();
+ v = *(const volatile uint8_t *)addr;
+ __compiler_membar();
+ return (v);
+}
+#define readb(addr) readb(addr)
+
+#undef writeb
static inline void
-writel(uint32_t b, void *addr)
+writeb(uint8_t v, volatile void *addr)
{
- *(volatile uint32_t *)addr = b;
+ __compiler_membar();
+ *(volatile uint8_t *)addr = v;
+ __compiler_membar();
}
+#define writeb(v, addr) writeb(v, addr)
-#undef writel_relaxed
+#undef readw
+static inline uint16_t
+readw(const volatile void *addr)
+{
+ uint16_t v;
+
+ __compiler_membar();
+ v = *(const volatile uint16_t *)addr;
+ __compiler_membar();
+ return (v);
+}
+#define readw(addr) readw(addr)
+
+#undef writew
static inline void
-writel_relaxed(uint32_t b, void *addr)
+writew(uint16_t v, volatile void *addr)
{
- *(volatile uint32_t *)addr = b;
+ __compiler_membar();
+ *(volatile uint16_t *)addr = v;
+ __compiler_membar();
}
+#define writew(v, addr) writew(v, addr)
+#undef readl
+static inline uint32_t
+readl(const volatile void *addr)
+{
+ uint32_t v;
+
+ __compiler_membar();
+ v = *(const volatile uint32_t *)addr;
+ __compiler_membar();
+ return (v);
+}
+#define readl(addr) readl(addr)
+
+#undef writel
+static inline void
+writel(uint32_t v, volatile void *addr)
+{
+ __compiler_membar();
+ *(volatile uint32_t *)addr = v;
+ __compiler_membar();
+}
+#define writel(v, addr) writel(v, addr)
+
+#undef readq
#undef writeq
+#ifdef __LP64__
+static inline uint64_t
+readq(const volatile void *addr)
+{
+ uint64_t v;
+
+ __compiler_membar();
+ v = *(const volatile uint64_t *)addr;
+ __compiler_membar();
+ return (v);
+}
+#define readq(addr) readq(addr)
+
static inline void
-writeq(uint64_t b, void *addr)
+writeq(uint64_t v, volatile void *addr)
{
- *(volatile uint64_t *)addr = b;
+ __compiler_membar();
+ *(volatile uint64_t *)addr = v;
+ __compiler_membar();
}
+#define writeq(v, addr) writeq(v, addr)
+#endif
-#undef writeb
+/* Access little-endian MMIO registers atomically without memory barriers. */
+
+#undef readb_relaxed
+static inline uint8_t
+readb_relaxed(const volatile void *addr)
+{
+ return (*(const volatile uint8_t *)addr);
+}
+#define readb_relaxed(addr) readb_relaxed(addr)
+
+#undef writeb_relaxed
static inline void
-writeb(uint8_t b, void *addr)
+writeb_relaxed(uint8_t v, volatile void *addr)
{
- *(volatile uint8_t *)addr = b;
+ *(volatile uint8_t *)addr = v;
}
+#define writeb_relaxed(v, addr) writeb_relaxed(v, addr)
-#undef writew
+#undef readw_relaxed
+static inline uint16_t
+readw_relaxed(const volatile void *addr)
+{
+ return (*(const volatile uint16_t *)addr);
+}
+#define readw_relaxed(addr) readw_relaxed(addr)
+
+#undef writew_relaxed
static inline void
-writew(uint16_t b, void *addr)
+writew_relaxed(uint16_t v, volatile void *addr)
{
- *(volatile uint16_t *)addr = b;
+ *(volatile uint16_t *)addr = v;
}
+#define writew_relaxed(v, addr) writew_relaxed(v, addr)
+#undef readl_relaxed
+static inline uint32_t
+readl_relaxed(const volatile void *addr)
+{
+ return (*(const volatile uint32_t *)addr);
+}
+#define readl_relaxed(addr) readl_relaxed(addr)
+
+#undef writel_relaxed
+static inline void
+writel_relaxed(uint32_t v, volatile void *addr)
+{
+ *(volatile uint32_t *)addr = v;
+}
+#define writel_relaxed(v, addr) writel_relaxed(v, addr)
+
+#undef readq_relaxed
+#undef writeq_relaxed
+#ifdef __LP64__
+static inline uint64_t
+readq_relaxed(const volatile void *addr)
+{
+ return (*(const volatile uint64_t *)addr);
+}
+#define readq_relaxed(addr) readq_relaxed(addr)
+
+static inline void
+writeq_relaxed(uint64_t v, volatile void *addr)
+{
+ *(volatile uint64_t *)addr = v;
+}
+#define writeq_relaxed(v, addr) writeq_relaxed(v, addr)
+#endif
+
+/* XXX On Linux ioread and iowrite handle both MMIO and port IO. */
+
#undef ioread8
static inline uint8_t
ioread8(const volatile void *addr)
{
- return *(const volatile uint8_t *)addr;
+ return (readb(addr));
}
+#define ioread8(addr) ioread8(addr)
#undef ioread16
static inline uint16_t
ioread16(const volatile void *addr)
{
- return *(const volatile uint16_t *)addr;
+ return (readw(addr));
}
+#define ioread16(addr) ioread16(addr)
#undef ioread16be
static inline uint16_t
ioread16be(const volatile void *addr)
{
- return be16toh(*(const volatile uint16_t *)addr);
+ return (bswap16(readw(addr)));
}
+#define ioread16be(addr) ioread16be(addr)
#undef ioread32
static inline uint32_t
ioread32(const volatile void *addr)
{
- return *(const volatile uint32_t *)addr;
+ return (readl(addr));
}
+#define ioread32(addr) ioread32(addr)
#undef ioread32be
static inline uint32_t
ioread32be(const volatile void *addr)
{
- return be32toh(*(const volatile uint32_t *)addr);
+ return (bswap32(readl(addr)));
}
+#define ioread32be(addr) ioread32be(addr)
#undef iowrite8
static inline void
iowrite8(uint8_t v, volatile void *addr)
{
- *(volatile uint8_t *)addr = v;
+ writeb(v, addr);
}
+#define iowrite8(v, addr) iowrite8(v, addr)
#undef iowrite16
static inline void
iowrite16(uint16_t v, volatile void *addr)
{
- *(volatile uint16_t *)addr = v;
+ writew(v, addr);
}
+#define iowrite16 iowrite16
#undef iowrite32
static inline void
iowrite32(uint32_t v, volatile void *addr)
{
- *(volatile uint32_t *)addr = v;
+ writel(v, addr);
}
+#define iowrite32(v, addr) iowrite32(v, addr)
#undef iowrite32be
static inline void
iowrite32be(uint32_t v, volatile void *addr)
{
- *(volatile uint32_t *)addr = htobe32(v);
+ writel(bswap32(v), addr);
}
-
-#undef readb
-static inline uint8_t
-readb(const volatile void *addr)
-{
- return *(const volatile uint8_t *)addr;
-}
-
-#undef readw
-static inline uint16_t
-readw(const volatile void *addr)
-{
- return *(const volatile uint16_t *)addr;
-}
-
-#undef readl
-static inline uint32_t
-readl(const volatile void *addr)
-{
- return *(const volatile uint32_t *)addr;
-}
+#define iowrite32be(v, addr) iowrite32be(v, addr)
#if defined(__i386__) || defined(__amd64__)
static inline void
_______________________________________________
svn-src-head@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-head
To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
