/* SPDX-License-Identifier: GPL-2.0 */
/*
* Definitions for using the Apple Descriptor-Based DMA controller
* in Power Macintosh computers.
*
* Copyright (C) 1996 Paul Mackerras.
*/
#ifdef __KERNEL__
#ifndef _ASM_DBDMA_H_
#define _ASM_DBDMA_H_
/*
* DBDMA control/status registers. All little-endian.
*/
struct dbdma_regs {
unsigned int control; /* lets you change bits in status */
unsigned int status; /* DMA and device status bits (see below) */
unsigned int cmdptr_hi; /* upper 32 bits of command address */
unsigned int cmdptr; /* (lower 32 bits of) command address (phys) */
unsigned int intr_sel; /* select interrupt condition bit */
unsigned int br_sel; /* select branch condition bit */
unsigned int wait_sel; /* select wait condition bit */
unsigned int xfer_mode;
unsigned int data2ptr_hi;
unsigned int data2ptr;
unsigned int res1;
unsigned int address_hi;
unsigned int br_addr_hi;
unsigned int res2[3];
};
/* Bits in control and status registers */
#define RUN 0x8000
#define PAUSE 0x4000
#define FLUSH 0x2000
#define WAKE 0x1000
#define DEAD 0x0800
#define ACTIVE 0x0400
#define BT 0x0100
#define DEVSTAT 0x00ff
/*
* DBDMA command structure. These fields are all little-endian!
*/
struct dbdma_cmd {
__le16 req_count; /* requested byte transfer count */
__le16 command; /* command word (has bit-fields) */
__le32 phy_addr; /* physical data address */
__le32 cmd_dep; /* command-dependent field */
__le16 res_count; /* residual count after completion */
__le16 xfer_status; /* transfer status */
};
/* DBDMA command values in command field */
#define OUTPUT_MORE 0 /* transfer memory data to stream */
#define OUTPUT_LAST 0x1000 /* ditto followed by end marker */
#define INPUT_MORE 0x2000 /* transfer stream data to memory */
#define INPUT_LAST 0x3000 /* ditto, expect end marker */
#define STORE_WORD 0x4000 /* write word (4 bytes) to device reg */
#define LOAD_WORD 0x5000 /* read word (4 bytes) from device reg */
#define DBDMA_NOP 0x6000 /* do nothing */
#define DBDMA_STOP 0x7000 /* suspend processing */
/* Key values in command field */
#define KEY_STREAM0 0 /* usual data stream */
#define KEY_STREAM1 0x100 /* control/status stream */
#define KEY_STREAM2 0x200 /* device-dependent stream */
#define KEY_STREAM3 0x300 /* device-dependent stream */
#define KEY_REGS 0x500 /* device register space */
#define KEY_SYSTEM 0x600 /* system memory-mapped space */
#define KEY_DEVICE 0x700 /* device memory-mapped space */
/* Interrupt control values in command field */
#define INTR_NEVER 0 /* don't interrupt */
#define INTR_IFSET 0x10 /* intr if condition bit is 1 */
#define INTR_IFCLR 0x20 /* intr if condition bit is 0 */
#define INTR_ALWAYS 0x30 /* always interrupt */
/* Branch control values in command field */
#define BR_NEVER 0 /* don't branch */
#define BR_IFSET 0x4 /* branch if condition bit is 1 */
#define BR_IFCLR 0x8 /* branch if condition bit is 0 */
#define BR_ALWAYS 0xc /* always branch */
/* Wait control values in command field */
#define WAIT_NEVER 0 /* don't wait */
#define WAIT_IFSET 1 /* wait if condition bit is 1 */
#define WAIT_IFCLR 2 /* wait if condition bit is 0 */
#define WAIT_ALWAYS 3 /* always wait */
/* Align an address for a DBDMA command structure */
#define DBDMA_ALIGN(x) (((unsigned long)(x) + sizeof(struct dbdma_cmd) - 1) \
& -sizeof(struct dbdma_cmd))
/* Useful macros */
#define DBDMA_DO_STOP(regs) do { \
out_le32(&((regs)->control), (RUN|FLUSH)<<16); \
while(in_le32(&((regs)->status)) & (ACTIVE|FLUSH)) \
; \
} while(0)
#define DBDMA_DO_RESET(regs) do { \
out_le32(&((regs)->control), (ACTIVE|DEAD|WAKE|FLUSH|PAUSE|RUN)<<16);\
while(in_le32(&((regs)->status)) & (RUN)) \
; \
} while(0)
#endif /* _ASM_DBDMA_H_ */
#endif /* __KERNEL__ */
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