summaryrefslogtreecommitdiff
path: root/hw/xfree86/os-support/misc/BUSmemcpy.c
diff options
context:
space:
mode:
Diffstat (limited to 'hw/xfree86/os-support/misc/BUSmemcpy.c')
-rw-r--r--hw/xfree86/os-support/misc/BUSmemcpy.c409
1 files changed, 409 insertions, 0 deletions
diff --git a/hw/xfree86/os-support/misc/BUSmemcpy.c b/hw/xfree86/os-support/misc/BUSmemcpy.c
new file mode 100644
index 000000000..acef268a1
--- /dev/null
+++ b/hw/xfree86/os-support/misc/BUSmemcpy.c
@@ -0,0 +1,409 @@
+
+/****************************************************************************
+
+ For Alpha Linux, BusToMem() and MemToBus() can be simply memcpy(), BUT:
+ we need to prevent unaligned operations when accessing DENSE space on the BUS,
+ as the video memory is mmap'd that way. The below code does this.
+
+NOTE: we could simply use the "memcpy()" from LIBC here, but that, currently, is
+ not as fast.
+
+Thanks to Linus Torvalds for contributing this code.
+
+****************************************************************************/
+
+/* $XFree86: xc/programs/Xserver/hw/xfree86/os-support/misc/BUSmemcpy.c,v 1.4 2000/02/12 20:45:44 dawes Exp $ */
+
+#include "X.h"
+#include "xf86.h"
+#include "xf86Priv.h"
+#include "xf86_OSlib.h"
+
+#ifdef __alpha__
+
+#include "compiler.h"
+
+/*
+ * The Jensen lacks dense memory, thus we have to address the bus via
+ * the sparse addressing scheme. These routines are only used in s3im.c
+ * Non time critical code uses SlowBCopy_{from/to} bus.
+ *
+ * Martin Ostermann (ost@comnets.rwth-aachen.de) - Apr.-Sep. 1996
+ */
+
+#ifdef TEST_JENSEN_CODE /* define to test the Sparse addressing on a non-Jensen */
+#define LWORD_CODING (0x18)
+#define SPARSE (5)
+#else
+#define LWORD_CODING (0x60)
+#define SPARSE (7)
+#endif
+
+void
+xf86JensenMemToBus(char *Base, long dst, long src, int count)
+{
+ if( ((long)src^((long)dst)) & 3) {
+ /* src & dst are NOT aligned to each other */
+ unsigned long addr;
+ unsigned long low_word, high_word,last_read;
+ long rm,loop;
+ unsigned long tmp,org,org2,mask,src_org,count_org;
+
+ src_org=src;
+ count_org=count;
+
+ /* add EISA longword coding and round off*/
+ addr = (long)(Base+(dst<<SPARSE) + LWORD_CODING) & ~(3<<SPARSE);
+ rm = (long)dst & 3;
+ count += rm;
+
+ count = count_org + rm;
+ org = *(volatile unsigned int *)addr;
+ __asm__("ldq_u %0,%1"
+ :"=r" (low_word):"m" (*(unsigned long *)(src_org)));
+ src = src_org - rm;
+ if( count > 4 ) {
+ last_read = src_org+count_org - 1;
+ __asm__("ldq_u %0,%1"
+ :"=r" (high_word):"m" (*(unsigned long *)(src+4)));
+ __asm__("extll %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" ((unsigned long)(src)));
+ __asm__("extlh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" ((unsigned long)(src)));
+ tmp |= low_word;
+ src += 4;
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" (rm));
+ __asm__("mskql %1,%2,%0"
+ :"=r" (org2)
+ :"r" (org), "r" (rm));
+ tmp |= org2;
+
+ loop = (count-4) >> 2; /* loop eqv. count>=4 ; count -= 4 */
+ while (loop) {
+ /* tmp to be stored completly -- need to read next word*/
+ low_word = high_word;
+ *(volatile unsigned int *) (addr) = tmp;
+ __asm__("ldq_u %0,%1"
+ :"=r" (high_word):"m" (*(unsigned long*)(src+4)));
+ loop --;
+ __asm__("extll %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" ((unsigned long)src));
+ __asm__("extlh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" ((unsigned long)src));
+ src += 4;
+ tmp |= low_word;
+ addr += 4<<SPARSE;
+ }
+ if ( count & 3 ) {
+ /* Store tmp completly, and possibly read one more word.*/
+ *(volatile unsigned int *) (addr) = tmp;
+ __asm__("ldq_u %0,%1"
+ :"=r" (tmp):"m" (*((unsigned long *)(last_read)) ));
+ addr += 4<<SPARSE;
+ __asm__("extll %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (high_word), "r" ((unsigned long)src));
+ __asm__("extlh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" ((unsigned long)src));
+ tmp |= low_word;
+ org = *(volatile unsigned int *)addr;
+
+ __asm__("mskql %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" (count&3));
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (org)
+ :"r" (org), "r" (count&3));
+
+ tmp |= org;
+ }
+ *(volatile unsigned int *) (addr) = tmp;
+ return;
+ } else { /* count > 4 */
+ __asm__("ldq_u %0,%1"
+ :"=r" (high_word):"m" (*(unsigned long *)(src+4)));
+ __asm__("extll %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" ((unsigned long)(src)));
+ __asm__("extlh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" ((unsigned long)(src)));
+ tmp |= low_word;
+ if( count < 4 ) {
+
+ mask = -1;
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (mask)
+ :"r" (mask), "r" (rm));
+ __asm__("mskql %1,%2,%0"
+ :"=r" (mask)
+ :"r" (mask), "r" (count));
+ tmp = (tmp & mask) | (org & ~mask);
+ *(volatile unsigned int *) (addr) = tmp;
+ return;
+ } else {
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" (rm));
+ __asm__("mskql %1,%2,%0"
+ :"=r" (org2)
+ :"r" (org), "r" (rm));
+
+ tmp |= org2;
+ *(volatile unsigned int *) (addr) = tmp;
+ return;
+ }
+ }
+ } else { /* src & dst are aligned to each other */
+ unsigned long addr;
+ unsigned int tmp,org,rm;
+ unsigned int *src_r;
+
+ /* add EISA longword coding and round off*/
+ addr = (long)(Base+(dst<<SPARSE) + LWORD_CODING) & ~(3<<SPARSE);
+
+ src_r = (unsigned int*)((long)src & ~3L);
+ rm=(long)src & 3;
+ count += rm;
+
+ tmp = *src_r;
+ org = *(volatile unsigned int *)addr;
+
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" (rm));
+ __asm__("mskql %1,%2,%0"
+ :"=r" (org)
+ :"r" (org), "r" (rm));
+
+ tmp |= org;
+
+ while (count > 4) {
+ *(volatile unsigned int *) addr = tmp;
+ addr += 4<<SPARSE;
+ src_r += 1;
+ tmp = *src_r;
+ count -= 4;
+ }
+
+ org = *(volatile unsigned int *)addr;
+ __asm__("mskql %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (tmp), "r" (count));
+ __asm__("mskqh %1,%2,%0"
+ :"=r" (org)
+ :"r" (org), "r" (count));
+ tmp |= org;
+ *(volatile unsigned int *) (addr) = tmp;
+ }
+}
+
+void
+xf86JensenBusToMem(char *Base, char *dst, unsigned long src, int count)
+{
+#if 0
+ /* Optimization of BusToMem() is left as an exercise to the reader ;-)
+ * Consider that ldq_u/extlh/extll won't work because of the bus being
+ * only 4 bytes wide!
+ */
+#else
+ unsigned long addr;
+ long result;
+
+ addr = (unsigned long)(Base+(src<<SPARSE)) ;
+ while( addr & (3<<SPARSE) ){
+ if(count <= 0) return;
+ result = *(volatile int *) addr;
+ result >>= ((addr>>SPARSE) & 3) * 8;
+ *dst++ = (char) result;
+ addr += 1<<SPARSE;
+ count--;
+ }
+ count -=4;
+ while(count >= 0){
+ int i;
+
+ result = *(volatile int *) (addr+LWORD_CODING);
+ for(i=4;i--;) {
+ *dst++ = (char) result;
+ result >>= 8;
+ }
+ addr += 4<<SPARSE;
+ count -= 4;
+ }
+ count +=4;
+
+ while( count ){
+ result = *(volatile int *) addr;
+ result >>= ((addr>>SPARSE) & 3) * 8;
+ *dst++ = (char) result;
+ addr += 1<<SPARSE;
+ count--;
+ }
+#endif
+}
+
+
+static unsigned long __memcpy(unsigned long dest, unsigned long src, int n);
+
+void
+xf86BusToMem(unsigned char *dst, unsigned char *src, int len)
+{
+ __memcpy((unsigned long)dst, (unsigned long)src, len);
+}
+void
+xf86MemToBus(unsigned char *dst, unsigned char *src, int len)
+{
+ if (len == sizeof(int))
+ if (!(((long)src | (long)dst) & 3))
+ *((unsigned int*)dst) = *((unsigned int*)(src));
+ else {
+ int i;
+ if (((long)src) & 3)
+ i = ldl_u((unsigned int*)src);
+ else
+ i = *(unsigned int*)src;
+ if (((long)dst) & 3)
+ stl_u(i,(unsigned int*)dst);
+ else
+ *(unsigned int*)dst = i;
+ }
+ else
+ __memcpy((unsigned long)dst, (unsigned long)src, len);
+}
+
+/*
+ * linux/arch/alpha/lib/memcpy.c
+ *
+ * Copyright (C) 1995 Linus Torvalds, used with his permission.
+ */
+
+/*
+ * This is a reasonably optimized memcpy() routine.
+ */
+
+/*
+ * Note that the C code is written to be optimized into good assembly. However,
+ * at this point gcc is unable to sanely compile "if (n >= 0)", resulting in a
+ * explicit compare against 0 (instead of just using the proper "blt reg, xx" or
+ * "bge reg, xx"). I hope alpha-gcc will be fixed to notice this eventually..
+ */
+
+/*
+ * This should be done in one go with ldq_u*2/mask/stq_u. Do it
+ * with a macro so that we can fix it up later..
+ */
+#define ALIGN_DEST_TO8(d,s,n) \
+ while (d & 7) { \
+ if (n <= 0) return; \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+
+/*
+ * This should similarly be done with ldq_u*2/mask/stq. The destination
+ * is aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST(d,s,n) \
+ while (n > 0) { \
+ n--; \
+ *(char *) d = *(char *) s; \
+ d++; s++; \
+ }
+
+/*
+ * This should be done with ldq/mask/stq. The source and destination are
+ * aligned, but we don't fill in a full quad-word
+ */
+#define DO_REST_ALIGNED(d,s,n) DO_REST(d,s,n)
+
+/*
+ * This does unaligned memory copies. We want to avoid storing to
+ * an unaligned address, as that would do a read-modify-write cycle.
+ * We also want to avoid double-reading the unaligned reads.
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static __inline__ void __memcpy_unaligned(unsigned long d, unsigned long s, long n)
+{
+ ALIGN_DEST_TO8(d,s,n);
+ n -= 8; /* to avoid compare against 8 in the loop */
+ if (n >= 0) {
+ unsigned long low_word, high_word;
+ __asm__("ldq_u %0,%1":"=r" (low_word):"m" (*(unsigned long *) s));
+ do {
+ unsigned long tmp;
+ __asm__("ldq_u %0,%1":"=r" (high_word):"m" (*(unsigned long *)(s+8)));
+ n -= 8;
+ __asm__("extql %1,%2,%0"
+ :"=r" (low_word)
+ :"r" (low_word), "r" (s));
+ __asm__("extqh %1,%2,%0"
+ :"=r" (tmp)
+ :"r" (high_word), "r" (s));
+ s += 8;
+ *(unsigned long *) d = low_word | tmp;
+ d += 8;
+ low_word = high_word;
+ } while (n >= 0);
+ }
+ n += 8;
+ DO_REST(d,s,n);
+}
+
+/*
+ * Hmm.. Strange. The __asm__ here is there to make gcc use a integer register
+ * for the load-store. I don't know why, but it would seem that using a floating
+ * point register for the move seems to slow things down (very small difference,
+ * though).
+ *
+ * Note the ordering to try to avoid load (and address generation) latencies.
+ */
+static __inline__ void __memcpy_aligned(unsigned long d, unsigned long s, long n)
+{
+ ALIGN_DEST_TO8(d,s,n);
+ n -= 8;
+ while (n >= 0) {
+ unsigned long tmp;
+ __asm__("ldq %0,%1":"=r" (tmp):"m" (*(unsigned long *) s));
+ n -= 8;
+ s += 8;
+ *(unsigned long *) d = tmp;
+ d += 8;
+ }
+ n += 8;
+ DO_REST_ALIGNED(d,s,n);
+}
+
+static unsigned long __memcpy(unsigned long dest, unsigned long src, int n)
+{
+ if (!((dest ^ src) & 7)) {
+ __memcpy_aligned(dest, src, n);
+ return dest;
+ }
+ __memcpy_unaligned(dest, src, n);
+ return dest;
+}
+
+#else /* __alpha__ */
+
+void
+xf86BusToMem(unsigned char *dst, unsigned char *src, int len)
+{
+ memcpy(dst, src, len);
+}
+void
+xf86MemToBus(unsigned char *dst, unsigned char *src, int len)
+{
+ memcpy(dst, src, len);
+}
+
+#endif /* __alpha__ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 02:28:20 +0000