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#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 : addad 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], dmabp[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) &dmawp[MCFDMA_DMR], dmawp[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 */
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