1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Definitions for using the Apple Descriptor-Based DMA controller 4 * in Power Macintosh computers. 5 * 6 * Copyright (C) 1996 Paul Mackerras. 7 */ 8 9 #ifdef __KERNEL__ 10 #ifndef _ASM_DBDMA_H_ 11 #define _ASM_DBDMA_H_ 12 /* 13 * DBDMA control/status registers. All little-endian. 14 */ 15 struct dbdma_regs { 16 unsigned int control; /* lets you change bits in status */ 17 unsigned int status; /* DMA and device status bits (see below) */ 18 unsigned int cmdptr_hi; /* upper 32 bits of command address */ 19 unsigned int cmdptr; /* (lower 32 bits of) command address (phys) */ 20 unsigned int intr_sel; /* select interrupt condition bit */ 21 unsigned int br_sel; /* select branch condition bit */ 22 unsigned int wait_sel; /* select wait condition bit */ 23 unsigned int xfer_mode; 24 unsigned int data2ptr_hi; 25 unsigned int data2ptr; 26 unsigned int res1; 27 unsigned int address_hi; 28 unsigned int br_addr_hi; 29 unsigned int res2[3]; 30 }; 31 32 /* Bits in control and status registers */ 33 #define RUN 0x8000 34 #define PAUSE 0x4000 35 #define FLUSH 0x2000 36 #define WAKE 0x1000 37 #define DEAD 0x0800 38 #define ACTIVE 0x0400 39 #define BT 0x0100 40 #define DEVSTAT 0x00ff 41 42 /* 43 * DBDMA command structure. These fields are all little-endian! 44 */ 45 struct dbdma_cmd { 46 __le16 req_count; /* requested byte transfer count */ 47 __le16 command; /* command word (has bit-fields) */ 48 __le32 phy_addr; /* physical data address */ 49 __le32 cmd_dep; /* command-dependent field */ 50 __le16 res_count; /* residual count after completion */ 51 __le16 xfer_status; /* transfer status */ 52 }; 53 54 /* DBDMA command values in command field */ 55 #define OUTPUT_MORE 0 /* transfer memory data to stream */ 56 #define OUTPUT_LAST 0x1000 /* ditto followed by end marker */ 57 #define INPUT_MORE 0x2000 /* transfer stream data to memory */ 58 #define INPUT_LAST 0x3000 /* ditto, expect end marker */ 59 #define STORE_WORD 0x4000 /* write word (4 bytes) to device reg */ 60 #define LOAD_WORD 0x5000 /* read word (4 bytes) from device reg */ 61 #define DBDMA_NOP 0x6000 /* do nothing */ 62 #define DBDMA_STOP 0x7000 /* suspend processing */ 63 64 /* Key values in command field */ 65 #define KEY_STREAM0 0 /* usual data stream */ 66 #define KEY_STREAM1 0x100 /* control/status stream */ 67 #define KEY_STREAM2 0x200 /* device-dependent stream */ 68 #define KEY_STREAM3 0x300 /* device-dependent stream */ 69 #define KEY_REGS 0x500 /* device register space */ 70 #define KEY_SYSTEM 0x600 /* system memory-mapped space */ 71 #define KEY_DEVICE 0x700 /* device memory-mapped space */ 72 73 /* Interrupt control values in command field */ 74 #define INTR_NEVER 0 /* don't interrupt */ 75 #define INTR_IFSET 0x10 /* intr if condition bit is 1 */ 76 #define INTR_IFCLR 0x20 /* intr if condition bit is 0 */ 77 #define INTR_ALWAYS 0x30 /* always interrupt */ 78 79 /* Branch control values in command field */ 80 #define BR_NEVER 0 /* don't branch */ 81 #define BR_IFSET 0x4 /* branch if condition bit is 1 */ 82 #define BR_IFCLR 0x8 /* branch if condition bit is 0 */ 83 #define BR_ALWAYS 0xc /* always branch */ 84 85 /* Wait control values in command field */ 86 #define WAIT_NEVER 0 /* don't wait */ 87 #define WAIT_IFSET 1 /* wait if condition bit is 1 */ 88 #define WAIT_IFCLR 2 /* wait if condition bit is 0 */ 89 #define WAIT_ALWAYS 3 /* always wait */ 90 91 /* Align an address for a DBDMA command structure */ 92 #define DBDMA_ALIGN(x) (((unsigned long)(x) + sizeof(struct dbdma_cmd) - 1) \ 93 & -sizeof(struct dbdma_cmd)) 94 95 /* Useful macros */ 96 #define DBDMA_DO_STOP(regs) do { \ 97 out_le32(&((regs)->control), (RUN|FLUSH)<<16); \ 98 while(in_le32(&((regs)->status)) & (ACTIVE|FLUSH)) \ 99 ; \ 100 } while(0) 101 102 #define DBDMA_DO_RESET(regs) do { \ 103 out_le32(&((regs)->control), (ACTIVE|DEAD|WAKE|FLUSH|PAUSE|RUN)<<16);\ 104 while(in_le32(&((regs)->status)) & (RUN)) \ 105 ; \ 106 } while(0) 107 108 #endif /* _ASM_DBDMA_H_ */ 109 #endif /* __KERNEL__ */ 110