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Release 4.14 arch/m68k/include/asm/dma.h

/* 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; }

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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; }

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/* * 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) { }

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/* 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 }

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/* 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 }

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/* * 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; }

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/* * 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; }

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/* * 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); }

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#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; }

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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; }

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/* * 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) { }

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/* 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 }

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/* 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 }

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/* * 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; }

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/* * 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; }

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/* * 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); }

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#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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