summaryrefslogtreecommitdiffstats
path: root/src/arch/i386/include/io.h
diff options
context:
space:
mode:
authorMichael Brown2005-03-08 19:53:11 +0100
committerMichael Brown2005-03-08 19:53:11 +0100
commit3d6123e69ab879c72ff489afc5bf93ef0b7a94ce (patch)
tree9f3277569153a550fa8d81ebd61bd88f266eb8da /src/arch/i386/include/io.h
downloadipxe-3d6123e69ab879c72ff489afc5bf93ef0b7a94ce.tar.gz
ipxe-3d6123e69ab879c72ff489afc5bf93ef0b7a94ce.tar.xz
ipxe-3d6123e69ab879c72ff489afc5bf93ef0b7a94ce.zip
Initial revision
Diffstat (limited to 'src/arch/i386/include/io.h')
-rw-r--r--src/arch/i386/include/io.h246
1 files changed, 246 insertions, 0 deletions
diff --git a/src/arch/i386/include/io.h b/src/arch/i386/include/io.h
new file mode 100644
index 00000000..e351a0c1
--- /dev/null
+++ b/src/arch/i386/include/io.h
@@ -0,0 +1,246 @@
+#ifndef ETHERBOOT_IO_H
+#define ETHERBOOT_IO_H
+
+
+/* Amount of relocation etherboot is experiencing */
+extern unsigned long virt_offset;
+
+/* Don't require identity mapped physical memory,
+ * osloader.c is the only valid user at the moment.
+ */
+static inline unsigned long virt_to_phys(volatile const void *virt_addr)
+{
+ return ((unsigned long)virt_addr) + virt_offset;
+}
+
+static inline void *phys_to_virt(unsigned long phys_addr)
+{
+ return (void *)(phys_addr - virt_offset);
+}
+
+/* virt_to_bus converts an addresss inside of etherboot [_start, _end]
+ * into a memory access cards can use.
+ */
+#define virt_to_bus virt_to_phys
+
+
+/* bus_to_virt reverses virt_to_bus, the address must be output
+ * from virt_to_bus to be valid. This function does not work on
+ * all bus addresses.
+ */
+#define bus_to_virt phys_to_virt
+
+/* ioremap converts a random 32bit bus address into something
+ * etherboot can access.
+ */
+static inline void *ioremap(unsigned long bus_addr, unsigned long length __unused)
+{
+ return bus_to_virt(bus_addr);
+}
+
+/* iounmap cleans up anything ioremap had to setup */
+static inline void iounmap(void *virt_addr __unused)
+{
+ return;
+}
+
+/*
+ * This file contains the definitions for the x86 IO instructions
+ * inb/inw/inl/outb/outw/outl and the "string versions" of the same
+ * (insb/insw/insl/outsb/outsw/outsl). You can also use "pausing"
+ * versions of the single-IO instructions (inb_p/inw_p/..).
+ *
+ * This file is not meant to be obfuscating: it's just complicated
+ * to (a) handle it all in a way that makes gcc able to optimize it
+ * as well as possible and (b) trying to avoid writing the same thing
+ * over and over again with slight variations and possibly making a
+ * mistake somewhere.
+ */
+
+/*
+ * Thanks to James van Artsdalen for a better timing-fix than
+ * the two short jumps: using outb's to a nonexistent port seems
+ * to guarantee better timings even on fast machines.
+ *
+ * On the other hand, I'd like to be sure of a non-existent port:
+ * I feel a bit unsafe about using 0x80 (should be safe, though)
+ *
+ * Linus
+ */
+
+#ifdef SLOW_IO_BY_JUMPING
+#define __SLOW_DOWN_IO __asm__ __volatile__("jmp 1f\n1:\tjmp 1f\n1:")
+#else
+#define __SLOW_DOWN_IO __asm__ __volatile__("outb %al,$0x80")
+#endif
+
+#ifdef REALLY_SLOW_IO
+#define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
+#else
+#define SLOW_DOWN_IO __SLOW_DOWN_IO
+#endif
+
+/*
+ * readX/writeX() are used to access memory mapped devices. On some
+ * architectures the memory mapped IO stuff needs to be accessed
+ * differently. On the x86 architecture, we just read/write the
+ * memory location directly.
+ */
+#define readb(addr) (*(volatile unsigned char *) (addr))
+#define readw(addr) (*(volatile unsigned short *) (addr))
+#define readl(addr) (*(volatile unsigned int *) (addr))
+
+#define writeb(b,addr) ((*(volatile unsigned char *) (addr)) = (b))
+#define writew(b,addr) ((*(volatile unsigned short *) (addr)) = (b))
+#define writel(b,addr) ((*(volatile unsigned int *) (addr)) = (b))
+
+#define memcpy_fromio(a,b,c) memcpy((a),(void *)(b),(c))
+#define memcpy_toio(a,b,c) memcpy((void *)(a),(b),(c))
+
+/*
+ * Force strict CPU ordering.
+ * And yes, this is required on UP too when we're talking
+ * to devices.
+ *
+ * For now, "wmb()" doesn't actually do anything, as all
+ * Intel CPU's follow what Intel calls a *Processor Order*,
+ * in which all writes are seen in the program order even
+ * outside the CPU.
+ *
+ * I expect future Intel CPU's to have a weaker ordering,
+ * but I'd also expect them to finally get their act together
+ * and add some real memory barriers if so.
+ *
+ * Some non intel clones support out of order store. wmb() ceases to be a
+ * nop for these.
+ */
+
+#define mb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory")
+#define rmb() mb()
+#define wmb() mb();
+
+
+/*
+ * Talk about misusing macros..
+ */
+
+#define __OUT1(s,x) \
+extern void __out##s(unsigned x value, unsigned short port); \
+extern inline void __out##s(unsigned x value, unsigned short port) {
+
+#define __OUT2(s,s1,s2) \
+__asm__ __volatile__ ("out" #s " %" s1 "0,%" s2 "1"
+
+#define __OUT(s,s1,x) \
+__OUT1(s,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); } \
+__OUT1(s##c,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); } \
+__OUT1(s##_p,x) __OUT2(s,s1,"w") : : "a" (value), "d" (port)); SLOW_DOWN_IO; } \
+__OUT1(s##c_p,x) __OUT2(s,s1,"") : : "a" (value), "id" (port)); SLOW_DOWN_IO; }
+
+#define __IN1(s,x) \
+extern unsigned x __in##s(unsigned short port); \
+extern inline unsigned x __in##s(unsigned short port) { unsigned x _v;
+
+#define __IN2(s,s1,s2) \
+__asm__ __volatile__ ("in" #s " %" s2 "1,%" s1 "0"
+
+#define __IN(s,s1,x,i...) \
+__IN1(s,x) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); return _v; } \
+__IN1(s##c,x) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); return _v; } \
+__IN1(s##_p,x) __IN2(s,s1,"w") : "=a" (_v) : "d" (port) ,##i ); SLOW_DOWN_IO; return _v; } \
+__IN1(s##c_p,x) __IN2(s,s1,"") : "=a" (_v) : "id" (port) ,##i ); SLOW_DOWN_IO; return _v; }
+
+#define __INS(s) \
+extern void ins##s(unsigned short port, void * addr, unsigned long count); \
+extern inline void ins##s(unsigned short port, void * addr, unsigned long count) \
+{ __asm__ __volatile__ ("cld ; rep ; ins" #s \
+: "=D" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
+
+#define __OUTS(s) \
+extern void outs##s(unsigned short port, const void * addr, unsigned long count); \
+extern inline void outs##s(unsigned short port, const void * addr, unsigned long count) \
+{ __asm__ __volatile__ ("cld ; rep ; outs" #s \
+: "=S" (addr), "=c" (count) : "d" (port),"0" (addr),"1" (count)); }
+
+__IN(b,"", char)
+__IN(w,"",short)
+__IN(l,"", long)
+
+__OUT(b,"b",char)
+__OUT(w,"w",short)
+__OUT(l,,int)
+
+__INS(b)
+__INS(w)
+__INS(l)
+
+__OUTS(b)
+__OUTS(w)
+__OUTS(l)
+
+/*
+ * Note that due to the way __builtin_constant_p() works, you
+ * - can't use it inside a inline function (it will never be true)
+ * - you don't have to worry about side effects within the __builtin..
+ */
+#define outb(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outbc((val),(port)) : \
+ __outb((val),(port)))
+
+#define inb(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inbc(port) : \
+ __inb(port))
+
+#define outb_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outbc_p((val),(port)) : \
+ __outb_p((val),(port)))
+
+#define inb_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inbc_p(port) : \
+ __inb_p(port))
+
+#define outw(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outwc((val),(port)) : \
+ __outw((val),(port)))
+
+#define inw(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inwc(port) : \
+ __inw(port))
+
+#define outw_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outwc_p((val),(port)) : \
+ __outw_p((val),(port)))
+
+#define inw_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inwc_p(port) : \
+ __inw_p(port))
+
+#define outl(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outlc((val),(port)) : \
+ __outl((val),(port)))
+
+#define inl(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inlc(port) : \
+ __inl(port))
+
+#define outl_p(val,port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __outlc_p((val),(port)) : \
+ __outl_p((val),(port)))
+
+#define inl_p(port) \
+((__builtin_constant_p((port)) && (port) < 256) ? \
+ __inlc_p(port) : \
+ __inl_p(port))
+
+#endif /* ETHERBOOT_IO_H */