xref: /openbmc/linux/drivers/usb/musb/cppi_dma.h (revision 842ed298)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (C) 2005-2006 by Texas Instruments */
3 
4 #ifndef _CPPI_DMA_H_
5 #define _CPPI_DMA_H_
6 
7 #include <linux/slab.h>
8 #include <linux/list.h>
9 #include <linux/errno.h>
10 #include <linux/dmapool.h>
11 #include <linux/dmaengine.h>
12 
13 #include "musb_core.h"
14 #include "musb_dma.h"
15 
16 /* CPPI RX/TX state RAM */
17 
18 struct cppi_tx_stateram {
19 	u32 tx_head;			/* "DMA packet" head descriptor */
20 	u32 tx_buf;
21 	u32 tx_current;			/* current descriptor */
22 	u32 tx_buf_current;
23 	u32 tx_info;			/* flags, remaining buflen */
24 	u32 tx_rem_len;
25 	u32 tx_dummy;			/* unused */
26 	u32 tx_complete;
27 };
28 
29 struct cppi_rx_stateram {
30 	u32 rx_skipbytes;
31 	u32 rx_head;
32 	u32 rx_sop;			/* "DMA packet" head descriptor */
33 	u32 rx_current;			/* current descriptor */
34 	u32 rx_buf_current;
35 	u32 rx_len_len;
36 	u32 rx_cnt_cnt;
37 	u32 rx_complete;
38 };
39 
40 /* hw_options bits in CPPI buffer descriptors */
41 #define CPPI_SOP_SET	((u32)(1 << 31))
42 #define CPPI_EOP_SET	((u32)(1 << 30))
43 #define CPPI_OWN_SET	((u32)(1 << 29))	/* owned by cppi */
44 #define CPPI_EOQ_MASK	((u32)(1 << 28))
45 #define CPPI_ZERO_SET	((u32)(1 << 23))	/* rx saw zlp; tx issues one */
46 #define CPPI_RXABT_MASK	((u32)(1 << 19))	/* need more rx buffers */
47 
48 #define CPPI_RECV_PKTLEN_MASK 0xFFFF
49 #define CPPI_BUFFER_LEN_MASK 0xFFFF
50 
51 #define CPPI_TEAR_READY ((u32)(1 << 31))
52 
53 /* CPPI data structure definitions */
54 
55 #define	CPPI_DESCRIPTOR_ALIGN	16	/* bytes; 5-dec docs say 4-byte align */
56 
57 struct cppi_descriptor {
58 	/* hardware overlay */
59 	u32		hw_next;	/* next buffer descriptor Pointer */
60 	u32		hw_bufp;	/* i/o buffer pointer */
61 	u32		hw_off_len;	/* buffer_offset16, buffer_length16 */
62 	u32		hw_options;	/* flags:  SOP, EOP etc*/
63 
64 	struct cppi_descriptor *next;
65 	dma_addr_t	dma;		/* address of this descriptor */
66 	u32		buflen;		/* for RX: original buffer length */
67 } __attribute__ ((aligned(CPPI_DESCRIPTOR_ALIGN)));
68 
69 
70 struct cppi;
71 
72 /* CPPI  Channel Control structure */
73 struct cppi_channel {
74 	struct dma_channel	channel;
75 
76 	/* back pointer to the DMA controller structure */
77 	struct cppi		*controller;
78 
79 	/* which direction of which endpoint? */
80 	struct musb_hw_ep	*hw_ep;
81 	bool			transmit;
82 	u8			index;
83 
84 	/* DMA modes:  RNDIS or "transparent" */
85 	u8			is_rndis;
86 
87 	/* book keeping for current transfer request */
88 	dma_addr_t		buf_dma;
89 	u32			buf_len;
90 	u32			maxpacket;
91 	u32			offset;		/* dma requested */
92 
93 	void __iomem		*state_ram;	/* CPPI state */
94 
95 	struct cppi_descriptor	*freelist;
96 
97 	/* BD management fields */
98 	struct cppi_descriptor	*head;
99 	struct cppi_descriptor	*tail;
100 	struct cppi_descriptor	*last_processed;
101 
102 	/* use tx_complete in host role to track endpoints waiting for
103 	 * FIFONOTEMPTY to clear.
104 	 */
105 	struct list_head	tx_complete;
106 };
107 
108 /* CPPI DMA controller object */
109 struct cppi {
110 	struct dma_controller		controller;
111 	void __iomem			*mregs;		/* Mentor regs */
112 	void __iomem			*tibase;	/* TI/CPPI regs */
113 
114 	int				irq;
115 
116 	struct cppi_channel		tx[4];
117 	struct cppi_channel		rx[4];
118 
119 	struct dma_pool			*pool;
120 
121 	struct list_head		tx_complete;
122 };
123 
124 /* CPPI IRQ handler */
125 extern irqreturn_t cppi_interrupt(int, void *);
126 
127 struct cppi41_dma_channel {
128 	struct dma_channel channel;
129 	struct cppi41_dma_controller *controller;
130 	struct musb_hw_ep *hw_ep;
131 	struct dma_chan *dc;
132 	dma_cookie_t cookie;
133 	u8 port_num;
134 	u8 is_tx;
135 	u8 is_allocated;
136 	u8 usb_toggle;
137 
138 	dma_addr_t buf_addr;
139 	u32 total_len;
140 	u32 prog_len;
141 	u32 transferred;
142 	u32 packet_sz;
143 	struct list_head tx_check;
144 	int tx_zlp;
145 };
146 
147 #endif				/* end of ifndef _CPPI_DMA_H_ */
148