patch-2.4.10 linux/arch/mips/jazz/jazzdma.c

• Lines: 848
• Date: Sun Sep 9 10:43:01 2001
• Orig file: v2.4.9/linux/arch/mips/jazz/jazzdma.c
• Orig date: Thu Feb 24 22:52:30 2000

diff -u --recursive --new-file v2.4.9/linux/arch/mips/jazz/jazzdma.c linux/arch/mips/jazz/jazzdma.c
@@ -1,6 +1,4 @@
 /*
- * arch/mips/jazz/jazzdma.c
- *
  * Mips Jazz DMA controller support
  * Copyright (C) 1995, 1996 by Andreas Busse
  *
@@ -27,7 +25,7 @@
  */
 #define CONF_DEBUG_VDMA 0
 
-static unsigned long vdma_pagetable_start = 0;
+static unsigned long vdma_pagetable_start;
 
 /*
  * Debug stuff
@@ -44,16 +42,16 @@
  */
 static inline void vdma_pgtbl_init(void)
 {
-    int i;
-    unsigned long paddr = 0;
-    VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
-  
-    for (i=0; i<VDMA_PGTBL_ENTRIES; i++)
-    {
-        pgtbl[i].frame = paddr;
-        pgtbl[i].owner = VDMA_PAGE_EMPTY;
-        paddr += VDMA_PAGESIZE;
-    }
+	int i;
+	unsigned long paddr = 0;
+	VDMA_PGTBL_ENTRY *pgtbl =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
+
+	for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
+		pgtbl[i].frame = paddr;
+		pgtbl[i].owner = VDMA_PAGE_EMPTY;
+		paddr += VDMA_PAGESIZE;
+	}
 }
 
 /*
@@ -77,13 +75,12 @@
 	 */
 	vdma_pgtbl_init();
 
-	r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE,PHYSADDR(vdma_pagetable_start));
+	r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE,
+			  PHYSADDR(vdma_pagetable_start));
 	r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
 	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
 
 	printk("VDMA: R4030 DMA pagetables initialized.\n");
-
-	return KSEG0ADDR(vdma_pagetable_end);
 }
 
 /*
@@ -91,92 +88,90 @@
  */
 unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
 {
-    VDMA_PGTBL_ENTRY *entry = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
-    int first;
-    int last;
-    int pages;
-    unsigned int frame;
-    unsigned long laddr;
-    int i;
-    unsigned long flags;
-
-    /* check arguments */
-  
-    if (paddr > 0x1fffffff)
-    {
-        if (vdma_debug)
-            printk("vdma_alloc: Invalid physical address: %08lx\n",paddr);
-        return VDMA_ERROR;	/* invalid physical address */
-    }
-    if (size > 0x400000 || size == 0)
-    {
-        if (vdma_debug)
-            printk("vdma_alloc: Invalid size: %08lx\n",size);
-        return VDMA_ERROR;	/* invalid physical address */
-    }
-  
-    save_and_cli (flags);
-    /*
-     * Find free chunk
-     */
-    pages = (size + 4095) >> 12; /* no. of pages to allocate */
-    first = 0;
-    while (1)
-    {
-        while (entry[first].owner != VDMA_PAGE_EMPTY &&
-               first < VDMA_PGTBL_ENTRIES)
-            first++;
-        if (first+pages > VDMA_PGTBL_ENTRIES) { /* nothing free */
-	    restore_flags (flags);
-            return VDMA_ERROR;
-	}
-
-        last = first+1;
-        while (entry[last].owner == VDMA_PAGE_EMPTY && last-first < pages)
-            last++;
-    
-        if (last-first == pages)
-            break;			/* found */
-    }
-  
-    /*
-     * Mark pages as allocated
-     */
-    laddr = (first << 12) + (paddr & (VDMA_PAGESIZE-1));
-    frame = paddr & ~(VDMA_PAGESIZE-1);
-  
-    for (i=first; i<last; i++)
-    {
-        entry[i].frame = frame;
-        entry[i].owner = laddr;
-        frame += VDMA_PAGESIZE;
-    }
-
-    /*
-     * Update translation table and return logical start address
-     */
-    r4030_write_reg32(JAZZ_R4030_TRSTBL_INV,0);
-
-    if (vdma_debug > 1)
-        printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
-               pages,laddr);
-
-    if (vdma_debug > 2)
-    {
-        printk("LADDR: ");
-        for (i=first; i<last; i++)
-            printk("%08x ",i<<12);
-        printk("\nPADDR: ");
-        for (i=first; i<last; i++)
-            printk("%08x ",entry[i].frame);
-        printk("\nOWNER: ");
-        for (i=first; i<last; i++)
-            printk("%08x ",entry[i].owner);
-        printk("\n");
-    }
-  
-    restore_flags(flags);
-    return laddr;
+	VDMA_PGTBL_ENTRY *entry =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
+	int first;
+	int last;
+	int pages;
+	unsigned int frame;
+	unsigned long laddr;
+	int i;
+	unsigned long flags;
+
+	/* check arguments */
+
+	if (paddr > 0x1fffffff) {
+		if (vdma_debug)
+			printk("vdma_alloc: Invalid physical address: %08lx\n",
+			       paddr);
+		return VDMA_ERROR;	/* invalid physical address */
+	}
+	if (size > 0x400000 || size == 0) {
+		if (vdma_debug)
+			printk("vdma_alloc: Invalid size: %08lx\n", size);
+		return VDMA_ERROR;	/* invalid physical address */
+	}
+
+	save_and_cli(flags);
+	/*
+	 * Find free chunk
+	 */
+	pages = (size + 4095) >> 12;	/* no. of pages to allocate */
+	first = 0;
+	while (1) {
+		while (entry[first].owner != VDMA_PAGE_EMPTY &&
+		       first < VDMA_PGTBL_ENTRIES) first++;
+		if (first + pages > VDMA_PGTBL_ENTRIES) {	/* nothing free */
+			restore_flags(flags);
+			return VDMA_ERROR;
+		}
+
+		last = first + 1;
+		while (entry[last].owner == VDMA_PAGE_EMPTY
+		       && last - first < pages)
+			last++;
+
+		if (last - first == pages)
+			break;	/* found */
+	}
+
+	/*
+	 * Mark pages as allocated
+	 */
+	laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
+	frame = paddr & ~(VDMA_PAGESIZE - 1);
+
+	for (i = first; i < last; i++) {
+		entry[i].frame = frame;
+		entry[i].owner = laddr;
+		frame += VDMA_PAGESIZE;
+	}
+
+	/*
+	 * Update translation table and return logical start address
+	 */
+	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
+
+	if (vdma_debug > 1)
+		printk
+		    ("vdma_alloc: Allocated %d pages starting from %08lx\n",
+		     pages, laddr);
+
+	if (vdma_debug > 2) {
+		printk("LADDR: ");
+		for (i = first; i < last; i++)
+			printk("%08x ", i << 12);
+		printk("\nPADDR: ");
+		for (i = first; i < last; i++)
+			printk("%08x ", entry[i].frame);
+		printk("\nOWNER: ");
+		for (i = first; i < last; i++)
+			printk("%08x ", entry[i].owner);
+		printk("\n");
+	}
+
+	restore_flags(flags);
+	return laddr;
 }
 
 /*
@@ -186,102 +181,103 @@
  */
 int vdma_free(unsigned long laddr)
 {
-    VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
-    int i;
+	VDMA_PGTBL_ENTRY *pgtbl =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
+	int i;
+
+	i = laddr >> 12;
+
+	if (pgtbl[i].owner != laddr) {
+		printk
+		    ("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
+		     laddr);
+		return -1;
+	}
+
+	while (pgtbl[i].owner == laddr && i < VDMA_PGTBL_ENTRIES) {
+		pgtbl[i].owner = VDMA_PAGE_EMPTY;
+		i++;
+	}
 
-    i = laddr >> 12;
+	if (vdma_debug > 1)
+		printk("vdma_free: freed %ld pages starting from %08lx\n",
+		       i - (laddr >> 12), laddr);
 
-    if (pgtbl[i].owner != laddr)
-    {
-        printk("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
-               laddr);
-        return -1;
-    }
-  
-    while (pgtbl[i].owner == laddr && i < VDMA_PGTBL_ENTRIES)
-    {
-        pgtbl[i].owner = VDMA_PAGE_EMPTY;
-        i++;
-    }
-  
-    if (vdma_debug > 1)
-        printk("vdma_free: freed %ld pages starting from %08lx\n",
-               i-(laddr>>12),laddr);
-  
-    return 0;
+	return 0;
 }
 
 /*
  * Map certain page(s) to another physical address.
  * Caller must have allocated the page(s) before.
  */
-int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size)
+int vdma_remap(unsigned long laddr, unsigned long paddr,
+	       unsigned long size)
 {
-    VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
-    int first, pages, npages;
+	VDMA_PGTBL_ENTRY *pgtbl =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
+	int first, pages, npages;
+
+	if (laddr > 0xffffff) {
+		if (vdma_debug)
+			printk
+			    ("vdma_map: Invalid logical address: %08lx\n",
+			     laddr);
+		return -EINVAL;	/* invalid logical address */
+	}
+	if (paddr > 0x1fffffff) {
+		if (vdma_debug)
+			printk
+			    ("vdma_map: Invalid physical address: %08lx\n",
+			     paddr);
+		return -EINVAL;	/* invalid physical address */
+	}
+
+	npages = pages =
+	    (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
+	first = laddr >> 12;
+	if (vdma_debug)
+		printk("vdma_remap: first=%x, pages=%x\n", first, pages);
+	if (first + pages > VDMA_PGTBL_ENTRIES) {
+		if (vdma_debug)
+			printk("vdma_alloc: Invalid size: %08lx\n", size);
+		return -EINVAL;
+	}
+
+	paddr &= ~(VDMA_PAGESIZE - 1);
+	while (pages > 0 && first < VDMA_PGTBL_ENTRIES) {
+		if (pgtbl[first].owner != laddr) {
+			if (vdma_debug)
+				printk("Trying to remap other's pages.\n");
+			return -EPERM;	/* not owner */
+		}
+		pgtbl[first].frame = paddr;
+		paddr += VDMA_PAGESIZE;
+		first++;
+		pages--;
+	}
+
+	/*
+	 * Update translation table
+	 */
+	r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
+
+	if (vdma_debug > 2) {
+		int i;
+		pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
+		first = laddr >> 12;
+		printk("LADDR: ");
+		for (i = first; i < first + pages; i++)
+			printk("%08x ", i << 12);
+		printk("\nPADDR: ");
+		for (i = first; i < first + pages; i++)
+			printk("%08x ", pgtbl[i].frame);
+		printk("\nOWNER: ");
+		for (i = first; i < first + pages; i++)
+			printk("%08x ", pgtbl[i].owner);
+		printk("\n");
+	}
 
-    if (laddr > 0xffffff)
-    {
-        if (vdma_debug)
-            printk("vdma_map: Invalid logical address: %08lx\n",laddr);
-        return -EINVAL;		/* invalid logical address */
-    }
-    if (paddr > 0x1fffffff)
-    {
-        if (vdma_debug)
-            printk("vdma_map: Invalid physical address: %08lx\n",paddr);
-        return -EINVAL;		/* invalid physical address */
-    }
-  
-    npages = pages = (((paddr & (VDMA_PAGESIZE-1)) + size) >> 12) + 1;
-    first = laddr >> 12;
-    if (vdma_debug)
-        printk("vdma_remap: first=%x, pages=%x\n",first,pages);
-    if (first+pages > VDMA_PGTBL_ENTRIES)
-    {
-        if (vdma_debug)
-            printk("vdma_alloc: Invalid size: %08lx\n",size);
-        return -EINVAL;
-    }
-
-    paddr &= ~(VDMA_PAGESIZE-1);
-    while (pages > 0 && first < VDMA_PGTBL_ENTRIES)
-    {
-        if (pgtbl[first].owner != laddr)
-        {
-            if (vdma_debug)
-                printk("Trying to remap other's pages.\n");
-            return -EPERM;		/* not owner */
-        }
-        pgtbl[first].frame = paddr;
-        paddr += VDMA_PAGESIZE;
-        first++;
-        pages--;
-    }
-
-    /*
-     * Update translation table
-     */
-    r4030_write_reg32(JAZZ_R4030_TRSTBL_INV,0);
-  
-    if (vdma_debug > 2)
-    {
-        int i;
-        pages = (((paddr & (VDMA_PAGESIZE-1)) + size) >> 12) + 1;
-        first = laddr >> 12;
-        printk("LADDR: ");
-        for (i=first; i<first+pages; i++)
-            printk("%08x ",i<<12);
-        printk("\nPADDR: ");
-        for (i=first; i<first+pages; i++)
-            printk("%08x ",pgtbl[i].frame);
-        printk("\nOWNER: ");
-        for (i=first; i<first+pages; i++)
-            printk("%08x ",pgtbl[i].owner);
-        printk("\n");
-    }
-      
-    return 0;
+	return 0;
 }
 
 /*
@@ -291,22 +287,22 @@
  */
 unsigned long vdma_phys2log(unsigned long paddr)
 {
-    int i;
-    int frame;
-    VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
-
-    frame = paddr & ~(VDMA_PAGESIZE-1);
-
-    for (i=0; i<VDMA_PGTBL_ENTRIES; i++)
-    {
-        if (pgtbl[i].frame == frame)
-            break;
-    }
+	int i;
+	int frame;
+	VDMA_PGTBL_ENTRY *pgtbl =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
+
+	frame = paddr & ~(VDMA_PAGESIZE - 1);
+
+	for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
+		if (pgtbl[i].frame == frame)
+			break;
+	}
 
-    if (i == VDMA_PGTBL_ENTRIES)
-        return ~0UL;
+	if (i == VDMA_PGTBL_ENTRIES)
+		return ~0UL;
 
-    return (i<<12) + (paddr & (VDMA_PAGESIZE-1));
+	return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
 }
 
 /*
@@ -314,44 +310,47 @@
  */
 unsigned long vdma_log2phys(unsigned long laddr)
 {
-    VDMA_PGTBL_ENTRY *pgtbl = (VDMA_PGTBL_ENTRY *)vdma_pagetable_start;
+	VDMA_PGTBL_ENTRY *pgtbl =
+	    (VDMA_PGTBL_ENTRY *) vdma_pagetable_start;
 
-    return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE-1));
+	return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
 }
-  
+
 /*
  * Print DMA statistics
  */
 void vdma_stats(void)
 {
-    int i;
-  
-    printk("vdma_stats: CONFIG: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_CONFIG));
-    printk("R4030 translation table base: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
-    printk("R4030 translation table limit: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
-    printk("vdma_stats: INV_ADDR: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_INV_ADDR));
-    printk("vdma_stats: R_FAIL_ADDR: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
-    printk("vdma_stats: M_FAIL_ADDR: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
-    printk("vdma_stats: IRQ_SOURCE: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
-    printk("vdma_stats: I386_ERROR: %08x\n",
-           r4030_read_reg32(JAZZ_R4030_I386_ERROR));
-    printk("vdma_chnl_modes:   ");
-    for (i=0; i<8; i++)
-        printk("%04x ",
-               (unsigned)r4030_read_reg32(JAZZ_R4030_CHNL_MODE+(i<<5)));
-    printk("\n");
-    printk("vdma_chnl_enables: ");
-    for (i=0; i<8; i++)
-        printk("%04x ",
-               (unsigned)r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(i<<5)));
-    printk("\n");
+	int i;
+
+	printk("vdma_stats: CONFIG: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_CONFIG));
+	printk("R4030 translation table base: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
+	printk("R4030 translation table limit: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
+	printk("vdma_stats: INV_ADDR: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_INV_ADDR));
+	printk("vdma_stats: R_FAIL_ADDR: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
+	printk("vdma_stats: M_FAIL_ADDR: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
+	printk("vdma_stats: IRQ_SOURCE: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
+	printk("vdma_stats: I386_ERROR: %08x\n",
+	       r4030_read_reg32(JAZZ_R4030_I386_ERROR));
+	printk("vdma_chnl_modes:   ");
+	for (i = 0; i < 8; i++)
+		printk("%04x ",
+		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
+						   (i << 5)));
+	printk("\n");
+	printk("vdma_chnl_enables: ");
+	for (i = 0; i < 8; i++)
+		printk("%04x ",
+		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+						   (i << 5)));
+	printk("\n");
 }
 
 /*
@@ -363,33 +362,35 @@
  */
 void vdma_enable(int channel)
 {
-    int status;
-  
-    if (vdma_debug)
-        printk("vdma_enable: channel %d\n",channel);
-  
-    /*
-     * Check error conditions first
-     */
-    status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5));
-    if (status & 0x400)
-        printk("VDMA: Channel %d: Address error!\n",channel);
-    if (status & 0x200)
-        printk("VDMA: Channel %d: Memory error!\n",channel);
-
-    /*
-     * Clear all interrupt flags
-     */
-    r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5),
-		      r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5)) |
-                      R4030_TC_INTR | R4030_MEM_INTR | R4030_ADDR_INTR);
-
-    /*
-     * Enable the desired channel
-     */
-    r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5),
-                      r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5)) |
-                      R4030_CHNL_ENABLE);
+	int status;
+
+	if (vdma_debug)
+		printk("vdma_enable: channel %d\n", channel);
+
+	/*
+	 * Check error conditions first
+	 */
+	status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
+	if (status & 0x400)
+		printk("VDMA: Channel %d: Address error!\n", channel);
+	if (status & 0x200)
+		printk("VDMA: Channel %d: Memory error!\n", channel);
+
+	/*
+	 * Clear all interrupt flags
+	 */
+	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
+			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+					   (channel << 5)) | R4030_TC_INTR
+			  | R4030_MEM_INTR | R4030_ADDR_INTR);
+
+	/*
+	 * Enable the desired channel
+	 */
+	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
+			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+					   (channel << 5)) |
+			  R4030_CHNL_ENABLE);
 }
 
 /*
@@ -397,28 +398,34 @@
  */
 void vdma_disable(int channel)
 {
-    if (vdma_debug)
-    {
-        int status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5));
-
-        printk("vdma_disable: channel %d\n",channel);
-        printk("VDMA: channel %d status: %04x (%s) mode: "
-               "%02x addr: %06x count: %06x\n",
-               channel,status,((status & 0x600) ? "ERROR" : "OK"),
-               (unsigned)r4030_read_reg32(JAZZ_R4030_CHNL_MODE+(channel<<5)),
-               (unsigned)r4030_read_reg32(JAZZ_R4030_CHNL_ADDR+(channel<<5)),
-               (unsigned)r4030_read_reg32(JAZZ_R4030_CHNL_COUNT+(channel<<5)));
-    }
-  
-    r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5),
-                      r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5)) &
-                      ~R4030_CHNL_ENABLE);
-
-    /*
-     * After disabling a DMA channel a remote bus register should be
-     * read to ensure that the current DMA acknowledge cycle is completed.
-     */
-    *((volatile unsigned int *)JAZZ_DUMMY_DEVICE);
+	if (vdma_debug) {
+		int status =
+		    r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+				     (channel << 5));
+
+		printk("vdma_disable: channel %d\n", channel);
+		printk("VDMA: channel %d status: %04x (%s) mode: "
+		       "%02x addr: %06x count: %06x\n",
+		       channel, status,
+		       ((status & 0x600) ? "ERROR" : "OK"),
+		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
+						   (channel << 5)),
+		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
+						   (channel << 5)),
+		       (unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
+						   (channel << 5)));
+	}
+
+	r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
+			  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+					   (channel << 5)) &
+			  ~R4030_CHNL_ENABLE);
+
+	/*
+	 * After disabling a DMA channel a remote bus register should be
+	 * read to ensure that the current DMA acknowledge cycle is completed.
+	 */
+	*((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
 }
 
 /*
@@ -432,56 +439,60 @@
  */
 void vdma_set_mode(int channel, int mode)
 {
-    if (vdma_debug)
-        printk("vdma_set_mode: channel %d, mode 0x%x\n", channel, mode);
-
-    switch(channel)
-    {
-    case JAZZ_SCSI_DMA:			/* scsi */
-        r4030_write_reg32(JAZZ_R4030_CHNL_MODE+(channel<<5),
+	if (vdma_debug)
+		printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
+		       mode);
+
+	switch (channel) {
+	case JAZZ_SCSI_DMA:	/* scsi */
+		r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
 /*			  R4030_MODE_FAST | */
 /*			  R4030_MODE_BURST | */
-                          R4030_MODE_INTR_EN |
-                          R4030_MODE_WIDTH_16 |
-                          R4030_MODE_ATIME_80);
-        break;
-      
-    case JAZZ_FLOPPY_DMA:	/* floppy */
-        r4030_write_reg32(JAZZ_R4030_CHNL_MODE+(channel<<5),
+				  R4030_MODE_INTR_EN |
+				  R4030_MODE_WIDTH_16 |
+				  R4030_MODE_ATIME_80);
+		break;
+
+	case JAZZ_FLOPPY_DMA:	/* floppy */
+		r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
 /*			  R4030_MODE_FAST | */
 /*			  R4030_MODE_BURST | */
-                          R4030_MODE_INTR_EN |
-                          R4030_MODE_WIDTH_8 |
-                          R4030_MODE_ATIME_120);
-        break;
-
-    case JAZZ_AUDIOL_DMA:
-    case JAZZ_AUDIOR_DMA:
-        printk("VDMA: Audio DMA not supported yet.\n");
-        break;
-      
-    default:
-        printk("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
-               channel);
-    }
-  
-    switch(mode)
-    {
-    case DMA_MODE_READ:
-        r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5),
-                          r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5)) &
-                          ~R4030_CHNL_WRITE);
-        break;
-      
-    case DMA_MODE_WRITE:
-        r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5),
-                          r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5)) |
-                          R4030_CHNL_WRITE);
-      break;
-      
-    default:
-        printk("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",mode);
-    }
+				  R4030_MODE_INTR_EN |
+				  R4030_MODE_WIDTH_8 |
+				  R4030_MODE_ATIME_120);
+		break;
+
+	case JAZZ_AUDIOL_DMA:
+	case JAZZ_AUDIOR_DMA:
+		printk("VDMA: Audio DMA not supported yet.\n");
+		break;
+
+	default:
+		printk
+		    ("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
+		     channel);
+	}
+
+	switch (mode) {
+	case DMA_MODE_READ:
+		r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
+				  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+						   (channel << 5)) &
+				  ~R4030_CHNL_WRITE);
+		break;
+
+	case DMA_MODE_WRITE:
+		r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
+				  r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
+						   (channel << 5)) |
+				  R4030_CHNL_WRITE);
+		break;
+
+	default:
+		printk
+		    ("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
+		     mode);
+	}
 }
 
 /*
@@ -489,10 +500,11 @@
  */
 void vdma_set_addr(int channel, long addr)
 {
-    if (vdma_debug)
-        printk("vdma_set_addr: channel %d, addr %lx\n",channel,addr);
+	if (vdma_debug)
+		printk("vdma_set_addr: channel %d, addr %lx\n", channel,
+		       addr);
 
-    r4030_write_reg32(JAZZ_R4030_CHNL_ADDR+(channel<<5),addr);
+	r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
 }
 
 /*
@@ -500,25 +512,28 @@
  */
 void vdma_set_count(int channel, int count)
 {
-    if (vdma_debug)
-        printk("vdma_set_count: channel %d, count %08x\n",channel,(unsigned)count);
-  
-    r4030_write_reg32(JAZZ_R4030_CHNL_COUNT+(channel<<5),count);
+	if (vdma_debug)
+		printk("vdma_set_count: channel %d, count %08x\n", channel,
+		       (unsigned) count);
+
+	r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
 }
-     
+
 /*
  * Get Residual
  */
 int vdma_get_residue(int channel)
 {
-    int residual;
-  
-    residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT+(channel<<5));
-
-    if (vdma_debug)
-        printk("vdma_get_residual: channel %d: residual=%d\n",channel,residual);
-  
-    return residual;
+	int residual;
+
+	residual =
+	    r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));
+
+	if (vdma_debug)
+		printk("vdma_get_residual: channel %d: residual=%d\n",
+		       channel, residual);
+
+	return residual;
 }
 
 /*
@@ -526,12 +541,13 @@
  */
 int vdma_get_enable(int channel)
 {
-    int enable;
-    
-    enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE+(channel<<5));
-    
-    if (vdma_debug)
-	printk("vdma_get_enable: channel %d: enable=%d\n",channel,enable);
-    
-    return enable;
+	int enable;
+
+	enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
+
+	if (vdma_debug)
+		printk("vdma_get_enable: channel %d: enable=%d\n", channel,
+		       enable);
+
+	return enable;
 }