patch-2.1.23 linux/arch/sparc/ap1000/dma.c

• Lines: 75
• Date: Sun Jan 26 12:07:06 1997
• Orig file: v2.1.22/linux/arch/sparc/ap1000/dma.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v2.1.22/linux/arch/sparc/ap1000/dma.c linux/arch/sparc/ap1000/dma.c
@@ -0,0 +1,74 @@
+  /*
+   * Copyright 1996 The Australian National University.
+   * Copyright 1996 Fujitsu Laboratories Limited
+   * 
+   * This software may be distributed under the terms of the Gnu
+   * Public License version 2 or later
+  */
+/* dma routines for the AP1000 */
+#include <asm/ap1000/apservice.h>
+#include <asm/ap1000/apreg.h>
+#include <linux/mm.h>
+#include <linux/malloc.h>
+#include <asm/irq.h>
+#include <asm/pgtable.h>
+
+#define DMA_MAX_TRANS_SIZE2 (0xfffffc)
+
+int ap_dma_wait(int ch)
+{
+	int i = 0;
+	while (DMA_IN(ch+DMA_DMST) & DMA_DMST_AC) i++;
+	return i;
+}
+
+/* send some data out a dma channel */
+int ap_dma_go(unsigned long ch,unsigned int p,int size,unsigned long cmd)
+{
+  int rest;
+
+  p = mmu_v2p(p);
+
+  cmd |= DMA_DCMD_ST | DMA_DCMD_TYP_AUTO;
+
+#if 0
+  if (ap_dma_wait(ch)) {
+	  printk("WARNING: dma started when not complete\n");
+  }
+
+  if (cmd == DMA_DCMD_TD_MD && !(BIF_IN(BIF_SDCSR) & BIF_SDCSR_BG)) {
+	  ap_led(0xAA);
+	  printk("attempt to dma without holding the bus\n");
+	  return -1;
+  }
+#endif
+
+  /* reset the dma system */
+  DMA_OUT(ch + DMA_DMST,DMA_DMST_RST);
+
+  if (size <= DMA_MAX_TRANS_SIZE) {
+    DMA_OUT(ch + DMA_MADDR,(unsigned long)p);
+    DMA_OUT(ch + DMA_HSKIP,1);
+    DMA_OUT(ch + DMA_VSKIP,1);
+    DMA_OUT(ch + DMA_DCMD,cmd | B2W(size));
+    return 0;
+  } 
+
+  if (size <= DMA_MAX_TRANS_SIZE2) {
+    if(size & 0x3) size += 4;
+    rest = (size & (DMA_TRANS_BLOCK_SIZE - 1)) >> 2;
+    if (rest) {
+      DMA_OUT(ch + DMA_HDRP,(unsigned)p);
+      p += rest << 2;
+    }
+    DMA_OUT(ch + DMA_MADDR,(unsigned)p);
+    DMA_OUT(ch + DMA_HSKIP,size >> (2 + 6));
+    DMA_OUT(ch + DMA_VSKIP,1);
+    DMA_OUT(ch + DMA_DCMD,cmd | (rest << 16) | 64);
+    return 0;
+  }
+
+  printk("AP1000 DMA operation too big (%d bytes) - aborting\n",size);
+  return(-1);
+}
+