1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * MUSB OTG driver DMA controller abstraction 4 * 5 * Copyright 2005 Mentor Graphics Corporation 6 * Copyright (C) 2005-2006 by Texas Instruments 7 * Copyright (C) 2006-2007 Nokia Corporation 8 */ 9 10#ifndef __MUSB_DMA_H__ 11#define __MUSB_DMA_H__ 12 13struct musb_hw_ep; 14 15/* 16 * DMA Controller Abstraction 17 * 18 * DMA Controllers are abstracted to allow use of a variety of different 19 * implementations of DMA, as allowed by the Inventra USB cores. On the 20 * host side, usbcore sets up the DMA mappings and flushes caches; on the 21 * peripheral side, the gadget controller driver does. Responsibilities 22 * of a DMA controller driver include: 23 * 24 * - Handling the details of moving multiple USB packets 25 * in cooperation with the Inventra USB core, including especially 26 * the correct RX side treatment of short packets and buffer-full 27 * states (both of which terminate transfers). 28 * 29 * - Knowing the correlation between dma channels and the 30 * Inventra core's local endpoint resources and data direction. 31 * 32 * - Maintaining a list of allocated/available channels. 33 * 34 * - Updating channel status on interrupts, 35 * whether shared with the Inventra core or separate. 36 */ 37 38#define MUSB_HSDMA_BASE 0x200 39#define MUSB_HSDMA_INTR (MUSB_HSDMA_BASE + 0) 40#define MUSB_HSDMA_CONTROL 0x4 41#define MUSB_HSDMA_ADDRESS 0x8 42#define MUSB_HSDMA_COUNT 0xc 43 44#define DMA_ADDR_INVALID (~(dma_addr_t)0) 45 46#ifdef CONFIG_MUSB_PIO_ONLY 47#define is_dma_capable() (0) 48#else 49#define is_dma_capable() (1) 50#endif 51 52#ifdef CONFIG_USB_UX500_DMA 53#define musb_dma_ux500(musb) (musb->ops->quirks & MUSB_DMA_UX500) 54#else 55#define musb_dma_ux500(musb) 0 56#endif 57 58#ifdef CONFIG_USB_TI_CPPI41_DMA 59#define musb_dma_cppi41(musb) (musb->ops->quirks & MUSB_DMA_CPPI41) 60#else 61#define musb_dma_cppi41(musb) 0 62#endif 63 64#ifdef CONFIG_USB_TUSB_OMAP_DMA 65#define tusb_dma_omap(musb) (musb->ops->quirks & MUSB_DMA_TUSB_OMAP) 66#else 67#define tusb_dma_omap(musb) 0 68#endif 69 70#ifdef CONFIG_USB_INVENTRA_DMA 71#define musb_dma_inventra(musb) (musb->ops->quirks & MUSB_DMA_INVENTRA) 72#else 73#define musb_dma_inventra(musb) 0 74#endif 75 76#if defined(CONFIG_USB_TI_CPPI41_DMA) 77#define is_cppi_enabled(musb) musb_dma_cppi41(musb) 78#else 79#define is_cppi_enabled(musb) 0 80#endif 81 82/* 83 * DMA channel status ... updated by the dma controller driver whenever that 84 * status changes, and protected by the overall controller spinlock. 85 */ 86enum dma_channel_status { 87 /* unallocated */ 88 MUSB_DMA_STATUS_UNKNOWN, 89 /* allocated ... but not busy, no errors */ 90 MUSB_DMA_STATUS_FREE, 91 /* busy ... transactions are active */ 92 MUSB_DMA_STATUS_BUSY, 93 /* transaction(s) aborted due to ... dma or memory bus error */ 94 MUSB_DMA_STATUS_BUS_ABORT, 95 /* transaction(s) aborted due to ... core error or USB fault */ 96 MUSB_DMA_STATUS_CORE_ABORT 97}; 98 99struct dma_controller; 100 101/** 102 * struct dma_channel - A DMA channel. 103 * @private_data: channel-private data 104 * @max_len: the maximum number of bytes the channel can move in one 105 * transaction (typically representing many USB maximum-sized packets) 106 * @actual_len: how many bytes have been transferred 107 * @status: current channel status (updated e.g. on interrupt) 108 * @desired_mode: true if mode 1 is desired; false if mode 0 is desired 109 * 110 * channels are associated with an endpoint for the duration of at least 111 * one usb transfer. 112 */ 113struct dma_channel { 114 void *private_data; 115 /* FIXME not void* private_data, but a dma_controller * */ 116 size_t max_len; 117 size_t actual_len; 118 enum dma_channel_status status; 119 bool desired_mode; 120 bool rx_packet_done; 121}; 122 123/* 124 * dma_channel_status - return status of dma channel 125 * @c: the channel 126 * 127 * Returns the software's view of the channel status. If that status is BUSY 128 * then it's possible that the hardware has completed (or aborted) a transfer, 129 * so the driver needs to update that status. 130 */ 131static inline enum dma_channel_status 132dma_channel_status(struct dma_channel *c) 133{ 134 return (is_dma_capable() && c) ? c->status : MUSB_DMA_STATUS_UNKNOWN; 135} 136 137/** 138 * struct dma_controller - A DMA Controller. 139 * @musb: the usb controller 140 * @start: call this to start a DMA controller; 141 * return 0 on success, else negative errno 142 * @stop: call this to stop a DMA controller 143 * return 0 on success, else negative errno 144 * @channel_alloc: call this to allocate a DMA channel 145 * @channel_release: call this to release a DMA channel 146 * @channel_abort: call this to abort a pending DMA transaction, 147 * returning it to FREE (but allocated) state 148 * @dma_callback: invoked on DMA completion, useful to run platform 149 * code such IRQ acknowledgment. 150 * 151 * Controllers manage dma channels. 152 */ 153struct dma_controller { 154 struct musb *musb; 155 struct dma_channel *(*channel_alloc)(struct dma_controller *, 156 struct musb_hw_ep *, u8 is_tx); 157 void (*channel_release)(struct dma_channel *); 158 int (*channel_program)(struct dma_channel *channel, 159 u16 maxpacket, u8 mode, 160 dma_addr_t dma_addr, 161 u32 length); 162 int (*channel_abort)(struct dma_channel *); 163 int (*is_compatible)(struct dma_channel *channel, 164 u16 maxpacket, 165 void *buf, u32 length); 166 void (*dma_callback)(struct dma_controller *); 167}; 168 169/* called after channel_program(), may indicate a fault */ 170extern void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit); 171 172#ifdef CONFIG_MUSB_PIO_ONLY 173static inline struct dma_controller * 174musb_dma_controller_create(struct musb *m, void __iomem *io) 175{ 176 return NULL; 177} 178 179static inline void musb_dma_controller_destroy(struct dma_controller *d) { } 180 181#else 182 183extern struct dma_controller * 184(*musb_dma_controller_create)(struct musb *, void __iomem *); 185 186extern void (*musb_dma_controller_destroy)(struct dma_controller *); 187#endif 188 189/* Platform specific DMA functions */ 190extern struct dma_controller * 191musbhs_dma_controller_create(struct musb *musb, void __iomem *base); 192extern void musbhs_dma_controller_destroy(struct dma_controller *c); 193extern struct dma_controller * 194musbhs_dma_controller_create_noirq(struct musb *musb, void __iomem *base); 195extern irqreturn_t dma_controller_irq(int irq, void *private_data); 196 197extern struct dma_controller * 198tusb_dma_controller_create(struct musb *musb, void __iomem *base); 199extern void tusb_dma_controller_destroy(struct dma_controller *c); 200 201extern struct dma_controller * 202cppi41_dma_controller_create(struct musb *musb, void __iomem *base); 203extern void cppi41_dma_controller_destroy(struct dma_controller *c); 204 205extern struct dma_controller * 206ux500_dma_controller_create(struct musb *musb, void __iomem *base); 207extern void ux500_dma_controller_destroy(struct dma_controller *c); 208 209#endif /* __MUSB_DMA_H__ */ 210