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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/m68k/include/asm/dma.h
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/m68k/include/asm/dma.h498
1 files changed, 498 insertions, 0 deletions
diff --git a/arch/m68k/include/asm/dma.h b/arch/m68k/include/asm/dma.h
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+++ b/arch/m68k/include/asm/dma.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _M68K_DMA_H
+#define _M68K_DMA_H 1
+
+#ifdef CONFIG_COLDFIRE
+/*
+ * ColdFire DMA Model:
+ * ColdFire DMA supports two forms of DMA: Single and Dual address. Single
+ * address mode emits a source address, and expects that the device will either
+ * pick up the data (DMA READ) or source data (DMA WRITE). This implies that
+ * the device will place data on the correct byte(s) of the data bus, as the
+ * memory transactions are always 32 bits. This implies that only 32 bit
+ * devices will find single mode transfers useful. Dual address DMA mode
+ * performs two cycles: source read and destination write. ColdFire will
+ * align the data so that the device will always get the correct bytes, thus
+ * is useful for 8 and 16 bit devices. This is the mode that is supported
+ * below.
+ *
+ * AUG/22/2000 : added support for 32-bit Dual-Address-Mode (K) 2000
+ * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
+ *
+ * AUG/25/2000 : added support for 8, 16 and 32-bit Single-Address-Mode (K)2000
+ * Oliver Kamphenkel (O.Kamphenkel@tu-bs.de)
+ *
+ * APR/18/2002 : added proper support for MCF5272 DMA controller.
+ * Arthur Shipkowski (art@videon-central.com)
+ */
+
+#include <asm/coldfire.h>
+#include <asm/mcfsim.h>
+#include <asm/mcfdma.h>
+
+/*
+ * Set number of channels of DMA on ColdFire for different implementations.
+ */
+#if defined(CONFIG_M5249) || defined(CONFIG_M5307) || defined(CONFIG_M5407) || \
+ defined(CONFIG_M523x) || defined(CONFIG_M527x) || \
+ defined(CONFIG_M528x) || defined(CONFIG_M525x)
+
+#define MAX_M68K_DMA_CHANNELS 4
+#elif defined(CONFIG_M5272)
+#define MAX_M68K_DMA_CHANNELS 1
+#elif defined(CONFIG_M53xx)
+#define MAX_M68K_DMA_CHANNELS 0
+#else
+#define MAX_M68K_DMA_CHANNELS 2
+#endif
+
+extern unsigned int dma_base_addr[MAX_M68K_DMA_CHANNELS];
+extern unsigned int dma_device_address[MAX_M68K_DMA_CHANNELS];
+
+#if !defined(CONFIG_M5272)
+#define DMA_MODE_WRITE_BIT 0x01 /* Memory/IO to IO/Memory select */
+#define DMA_MODE_WORD_BIT 0x02 /* 8 or 16 bit transfers */
+#define DMA_MODE_LONG_BIT 0x04 /* or 32 bit transfers */
+#define DMA_MODE_SINGLE_BIT 0x08 /* single-address-mode */
+
+/* I/O to memory, 8 bits, mode */
+#define DMA_MODE_READ 0
+/* memory to I/O, 8 bits, mode */
+#define DMA_MODE_WRITE 1
+/* I/O to memory, 16 bits, mode */
+#define DMA_MODE_READ_WORD 2
+/* memory to I/O, 16 bits, mode */
+#define DMA_MODE_WRITE_WORD 3
+/* I/O to memory, 32 bits, mode */
+#define DMA_MODE_READ_LONG 4
+/* memory to I/O, 32 bits, mode */
+#define DMA_MODE_WRITE_LONG 5
+/* I/O to memory, 8 bits, single-address-mode */
+#define DMA_MODE_READ_SINGLE 8
+/* memory to I/O, 8 bits, single-address-mode */
+#define DMA_MODE_WRITE_SINGLE 9
+/* I/O to memory, 16 bits, single-address-mode */
+#define DMA_MODE_READ_WORD_SINGLE 10
+/* memory to I/O, 16 bits, single-address-mode */
+#define DMA_MODE_WRITE_WORD_SINGLE 11
+/* I/O to memory, 32 bits, single-address-mode */
+#define DMA_MODE_READ_LONG_SINGLE 12
+/* memory to I/O, 32 bits, single-address-mode */
+#define DMA_MODE_WRITE_LONG_SINGLE 13
+
+#else /* CONFIG_M5272 is defined */
+
+/* Source static-address mode */
+#define DMA_MODE_SRC_SA_BIT 0x01
+/* Two bits to select between all four modes */
+#define DMA_MODE_SSIZE_MASK 0x06
+/* Offset to shift bits in */
+#define DMA_MODE_SSIZE_OFF 0x01
+/* Destination static-address mode */
+#define DMA_MODE_DES_SA_BIT 0x10
+/* Two bits to select between all four modes */
+#define DMA_MODE_DSIZE_MASK 0x60
+/* Offset to shift bits in */
+#define DMA_MODE_DSIZE_OFF 0x05
+/* Size modifiers */
+#define DMA_MODE_SIZE_LONG 0x00
+#define DMA_MODE_SIZE_BYTE 0x01
+#define DMA_MODE_SIZE_WORD 0x02
+#define DMA_MODE_SIZE_LINE 0x03
+
+/*
+ * Aliases to help speed quick ports; these may be suboptimal, however. They
+ * do not include the SINGLE mode modifiers since the MCF5272 does not have a
+ * mode where the device is in control of its addressing.
+ */
+
+/* I/O to memory, 8 bits, mode */
+#define DMA_MODE_READ ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
+/* memory to I/O, 8 bits, mode */
+#define DMA_MODE_WRITE ((DMA_MODE_SIZE_BYTE << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_BYTE << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
+/* I/O to memory, 16 bits, mode */
+#define DMA_MODE_READ_WORD ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
+/* memory to I/O, 16 bits, mode */
+#define DMA_MODE_WRITE_WORD ((DMA_MODE_SIZE_WORD << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_WORD << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
+/* I/O to memory, 32 bits, mode */
+#define DMA_MODE_READ_LONG ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_SRC_SA_BIT)
+/* memory to I/O, 32 bits, mode */
+#define DMA_MODE_WRITE_LONG ((DMA_MODE_SIZE_LONG << DMA_MODE_DSIZE_OFF) | (DMA_MODE_SIZE_LONG << DMA_MODE_SSIZE_OFF) | DMA_DES_SA_BIT)
+
+#endif /* !defined(CONFIG_M5272) */
+
+#if !defined(CONFIG_M5272)
+/* enable/disable a specific DMA channel */
+static __inline__ void enable_dma(unsigned int dmanr)
+{
+ volatile unsigned short *dmawp;
+
+#ifdef DMA_DEBUG
+ printk("enable_dma(dmanr=%d)\n", dmanr);
+#endif
+
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+ dmawp[MCFDMA_DCR] |= MCFDMA_DCR_EEXT;
+}
+
+static __inline__ void disable_dma(unsigned int dmanr)
+{
+ volatile unsigned short *dmawp;
+ volatile unsigned char *dmapb;
+
+#ifdef DMA_DEBUG
+ printk("disable_dma(dmanr=%d)\n", dmanr);
+#endif
+
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+ dmapb = (unsigned char *) dma_base_addr[dmanr];
+
+ /* Turn off external requests, and stop any DMA in progress */
+ dmawp[MCFDMA_DCR] &= ~MCFDMA_DCR_EEXT;
+ dmapb[MCFDMA_DSR] = MCFDMA_DSR_DONE;
+}
+
+/*
+ * Clear the 'DMA Pointer Flip Flop'.
+ * Write 0 for LSB/MSB, 1 for MSB/LSB access.
+ * Use this once to initialize the FF to a known state.
+ * After that, keep track of it. :-)
+ * --- In order to do that, the DMA routines below should ---
+ * --- only be used while interrupts are disabled! ---
+ *
+ * This is a NOP for ColdFire. Provide a stub for compatibility.
+ */
+static __inline__ void clear_dma_ff(unsigned int dmanr)
+{
+}
+
+/* set mode (above) for a specific DMA channel */
+static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
+{
+
+ volatile unsigned char *dmabp;
+ volatile unsigned short *dmawp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
+#endif
+
+ dmabp = (unsigned char *) dma_base_addr[dmanr];
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+
+ /* Clear config errors */
+ dmabp[MCFDMA_DSR] = MCFDMA_DSR_DONE;
+
+ /* Set command register */
+ dmawp[MCFDMA_DCR] =
+ MCFDMA_DCR_INT | /* Enable completion irq */
+ MCFDMA_DCR_CS | /* Force one xfer per request */
+ MCFDMA_DCR_AA | /* Enable auto alignment */
+ /* single-address-mode */
+ ((mode & DMA_MODE_SINGLE_BIT) ? MCFDMA_DCR_SAA : 0) |
+ /* sets s_rw (-> r/w) high if Memory to I/0 */
+ ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_S_RW : 0) |
+ /* Memory to I/O or I/O to Memory */
+ ((mode & DMA_MODE_WRITE_BIT) ? MCFDMA_DCR_SINC : MCFDMA_DCR_DINC) |
+ /* 32 bit, 16 bit or 8 bit transfers */
+ ((mode & DMA_MODE_WORD_BIT) ? MCFDMA_DCR_SSIZE_WORD :
+ ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_SSIZE_LONG :
+ MCFDMA_DCR_SSIZE_BYTE)) |
+ ((mode & DMA_MODE_WORD_BIT) ? MCFDMA_DCR_DSIZE_WORD :
+ ((mode & DMA_MODE_LONG_BIT) ? MCFDMA_DCR_DSIZE_LONG :
+ MCFDMA_DCR_DSIZE_BYTE));
+
+#ifdef DEBUG_DMA
+ printk("%s(%d): dmanr=%d DSR[%x]=%x DCR[%x]=%x\n", __FILE__, __LINE__,
+ dmanr, (int) &dmabp[MCFDMA_DSR], dmabp[MCFDMA_DSR],
+ (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR]);
+#endif
+}
+
+/* Set transfer address for specific DMA channel */
+static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
+{
+ volatile unsigned short *dmawp;
+ volatile unsigned int *dmalp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
+#endif
+
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+
+ /* Determine which address registers are used for memory/device accesses */
+ if (dmawp[MCFDMA_DCR] & MCFDMA_DCR_SINC) {
+ /* Source incrementing, must be memory */
+ dmalp[MCFDMA_SAR] = a;
+ /* Set dest address, must be device */
+ dmalp[MCFDMA_DAR] = dma_device_address[dmanr];
+ } else {
+ /* Destination incrementing, must be memory */
+ dmalp[MCFDMA_DAR] = a;
+ /* Set source address, must be device */
+ dmalp[MCFDMA_SAR] = dma_device_address[dmanr];
+ }
+
+#ifdef DEBUG_DMA
+ printk("%s(%d): dmanr=%d DCR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
+ __FILE__, __LINE__, dmanr, (int) &dmawp[MCFDMA_DCR], dmawp[MCFDMA_DCR],
+ (int) &dmalp[MCFDMA_SAR], dmalp[MCFDMA_SAR],
+ (int) &dmalp[MCFDMA_DAR], dmalp[MCFDMA_DAR]);
+#endif
+}
+
+/*
+ * Specific for Coldfire - sets device address.
+ * Should be called after the mode set call, and before set DMA address.
+ */
+static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
+{
+#ifdef DMA_DEBUG
+ printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
+#endif
+
+ dma_device_address[dmanr] = a;
+}
+
+/*
+ * NOTE 2: "count" represents _bytes_.
+ */
+static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
+{
+ volatile unsigned short *dmawp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
+#endif
+
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+ dmawp[MCFDMA_BCR] = (unsigned short)count;
+}
+
+/*
+ * Get DMA residue count. After a DMA transfer, this
+ * should return zero. Reading this while a DMA transfer is
+ * still in progress will return unpredictable results.
+ * Otherwise, it returns the number of _bytes_ left to transfer.
+ */
+static __inline__ int get_dma_residue(unsigned int dmanr)
+{
+ volatile unsigned short *dmawp;
+ unsigned short count;
+
+#ifdef DMA_DEBUG
+ printk("get_dma_residue(dmanr=%d)\n", dmanr);
+#endif
+
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+ count = dmawp[MCFDMA_BCR];
+ return((int) count);
+}
+#else /* CONFIG_M5272 is defined */
+
+/*
+ * The MCF5272 DMA controller is very different than the controller defined above
+ * in terms of register mapping. For instance, with the exception of the 16-bit
+ * interrupt register (IRQ#85, for reference), all of the registers are 32-bit.
+ *
+ * The big difference, however, is the lack of device-requested DMA. All modes
+ * are dual address transfer, and there is no 'device' setup or direction bit.
+ * You can DMA between a device and memory, between memory and memory, or even between
+ * two devices directly, with any combination of incrementing and non-incrementing
+ * addresses you choose. This puts a crimp in distinguishing between the 'device
+ * address' set up by set_dma_device_addr.
+ *
+ * Therefore, there are two options. One is to use set_dma_addr and set_dma_device_addr,
+ * which will act exactly as above in -- it will look to see if the source is set to
+ * autoincrement, and if so it will make the source use the set_dma_addr value and the
+ * destination the set_dma_device_addr value. Otherwise the source will be set to the
+ * set_dma_device_addr value and the destination will get the set_dma_addr value.
+ *
+ * The other is to use the provided set_dma_src_addr and set_dma_dest_addr functions
+ * and make it explicit. Depending on what you're doing, one of these two should work
+ * for you, but don't mix them in the same transfer setup.
+ */
+
+/* enable/disable a specific DMA channel */
+static __inline__ void enable_dma(unsigned int dmanr)
+{
+ volatile unsigned int *dmalp;
+
+#ifdef DMA_DEBUG
+ printk("enable_dma(dmanr=%d)\n", dmanr);
+#endif
+
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+ dmalp[MCFDMA_DMR] |= MCFDMA_DMR_EN;
+}
+
+static __inline__ void disable_dma(unsigned int dmanr)
+{
+ volatile unsigned int *dmalp;
+
+#ifdef DMA_DEBUG
+ printk("disable_dma(dmanr=%d)\n", dmanr);
+#endif
+
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+
+ /* Turn off external requests, and stop any DMA in progress */
+ dmalp[MCFDMA_DMR] &= ~MCFDMA_DMR_EN;
+ dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
+}
+
+/*
+ * Clear the 'DMA Pointer Flip Flop'.
+ * Write 0 for LSB/MSB, 1 for MSB/LSB access.
+ * Use this once to initialize the FF to a known state.
+ * After that, keep track of it. :-)
+ * --- In order to do that, the DMA routines below should ---
+ * --- only be used while interrupts are disabled! ---
+ *
+ * This is a NOP for ColdFire. Provide a stub for compatibility.
+ */
+static __inline__ void clear_dma_ff(unsigned int dmanr)
+{
+}
+
+/* set mode (above) for a specific DMA channel */
+static __inline__ void set_dma_mode(unsigned int dmanr, char mode)
+{
+
+ volatile unsigned int *dmalp;
+ volatile unsigned short *dmawp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_mode(dmanr=%d,mode=%d)\n", dmanr, mode);
+#endif
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+ dmawp = (unsigned short *) dma_base_addr[dmanr];
+
+ /* Clear config errors */
+ dmalp[MCFDMA_DMR] |= MCFDMA_DMR_RESET;
+
+ /* Set command register */
+ dmalp[MCFDMA_DMR] =
+ MCFDMA_DMR_RQM_DUAL | /* Mandatory Request Mode setting */
+ MCFDMA_DMR_DSTT_SD | /* Set up addressing types; set to supervisor-data. */
+ MCFDMA_DMR_SRCT_SD | /* Set up addressing types; set to supervisor-data. */
+ /* source static-address-mode */
+ ((mode & DMA_MODE_SRC_SA_BIT) ? MCFDMA_DMR_SRCM_SA : MCFDMA_DMR_SRCM_IA) |
+ /* dest static-address-mode */
+ ((mode & DMA_MODE_DES_SA_BIT) ? MCFDMA_DMR_DSTM_SA : MCFDMA_DMR_DSTM_IA) |
+ /* burst, 32 bit, 16 bit or 8 bit transfers are separately configurable on the MCF5272 */
+ (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_DSTS_OFF) |
+ (((mode & DMA_MODE_SSIZE_MASK) >> DMA_MODE_SSIZE_OFF) << MCFDMA_DMR_SRCS_OFF);
+
+ dmawp[MCFDMA_DIR] |= MCFDMA_DIR_ASCEN; /* Enable completion interrupts */
+
+#ifdef DEBUG_DMA
+ printk("%s(%d): dmanr=%d DMR[%x]=%x DIR[%x]=%x\n", __FILE__, __LINE__,
+ dmanr, (int) &dmalp[MCFDMA_DMR], dmalp[MCFDMA_DMR],
+ (int) &dmawp[MCFDMA_DIR], dmawp[MCFDMA_DIR]);
+#endif
+}
+
+/* Set transfer address for specific DMA channel */
+static __inline__ void set_dma_addr(unsigned int dmanr, unsigned int a)
+{
+ volatile unsigned int *dmalp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_addr(dmanr=%d,a=%x)\n", dmanr, a);
+#endif
+
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+
+ /* Determine which address registers are used for memory/device accesses */
+ if (dmalp[MCFDMA_DMR] & MCFDMA_DMR_SRCM) {
+ /* Source incrementing, must be memory */
+ dmalp[MCFDMA_DSAR] = a;
+ /* Set dest address, must be device */
+ dmalp[MCFDMA_DDAR] = dma_device_address[dmanr];
+ } else {
+ /* Destination incrementing, must be memory */
+ dmalp[MCFDMA_DDAR] = a;
+ /* Set source address, must be device */
+ dmalp[MCFDMA_DSAR] = dma_device_address[dmanr];
+ }
+
+#ifdef DEBUG_DMA
+ printk("%s(%d): dmanr=%d DMR[%x]=%x SAR[%x]=%08x DAR[%x]=%08x\n",
+ __FILE__, __LINE__, dmanr, (int) &dmalp[MCFDMA_DMR], dmalp[MCFDMA_DMR],
+ (int) &dmalp[MCFDMA_DSAR], dmalp[MCFDMA_DSAR],
+ (int) &dmalp[MCFDMA_DDAR], dmalp[MCFDMA_DDAR]);
+#endif
+}
+
+/*
+ * Specific for Coldfire - sets device address.
+ * Should be called after the mode set call, and before set DMA address.
+ */
+static __inline__ void set_dma_device_addr(unsigned int dmanr, unsigned int a)
+{
+#ifdef DMA_DEBUG
+ printk("set_dma_device_addr(dmanr=%d,a=%x)\n", dmanr, a);
+#endif
+
+ dma_device_address[dmanr] = a;
+}
+
+/*
+ * NOTE 2: "count" represents _bytes_.
+ *
+ * NOTE 3: While a 32-bit register, "count" is only a maximum 24-bit value.
+ */
+static __inline__ void set_dma_count(unsigned int dmanr, unsigned int count)
+{
+ volatile unsigned int *dmalp;
+
+#ifdef DMA_DEBUG
+ printk("set_dma_count(dmanr=%d,count=%d)\n", dmanr, count);
+#endif
+
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+ dmalp[MCFDMA_DBCR] = count;
+}
+
+/*
+ * Get DMA residue count. After a DMA transfer, this
+ * should return zero. Reading this while a DMA transfer is
+ * still in progress will return unpredictable results.
+ * Otherwise, it returns the number of _bytes_ left to transfer.
+ */
+static __inline__ int get_dma_residue(unsigned int dmanr)
+{
+ volatile unsigned int *dmalp;
+ unsigned int count;
+
+#ifdef DMA_DEBUG
+ printk("get_dma_residue(dmanr=%d)\n", dmanr);
+#endif
+
+ dmalp = (unsigned int *) dma_base_addr[dmanr];
+ count = dmalp[MCFDMA_DBCR];
+ return(count);
+}
+
+#endif /* !defined(CONFIG_M5272) */
+#endif /* CONFIG_COLDFIRE */
+
+/* it's useless on the m68k, but unfortunately needed by the new
+ bootmem allocator (but this should do it for this) */
+#define MAX_DMA_ADDRESS PAGE_OFFSET
+
+#define MAX_DMA_CHANNELS 8
+
+extern int request_dma(unsigned int dmanr, const char * device_id); /* reserve a DMA channel */
+extern void free_dma(unsigned int dmanr); /* release it again */
+
+#ifdef CONFIG_PCI
+extern int isa_dma_bridge_buggy;
+#else
+#define isa_dma_bridge_buggy (0)
+#endif
+
+#endif /* _M68K_DMA_H */