xref: /openbmc/linux/drivers/dma/hsu/hsu.h (revision eb3fcf00)
1 /*
2  * Driver for the High Speed UART DMA
3  *
4  * Copyright (C) 2015 Intel Corporation
5  *
6  * Partially based on the bits found in drivers/tty/serial/mfd.c.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #ifndef __DMA_HSU_H__
14 #define __DMA_HSU_H__
15 
16 #include <linux/spinlock.h>
17 #include <linux/dma/hsu.h>
18 
19 #include "../virt-dma.h"
20 
21 #define HSU_CH_SR		0x00			/* channel status */
22 #define HSU_CH_CR		0x04			/* channel control */
23 #define HSU_CH_DCR		0x08			/* descriptor control */
24 #define HSU_CH_BSR		0x10			/* FIFO buffer size */
25 #define HSU_CH_MTSR		0x14			/* minimum transfer size */
26 #define HSU_CH_DxSAR(x)		(0x20 + 8 * (x))	/* desc start addr */
27 #define HSU_CH_DxTSR(x)		(0x24 + 8 * (x))	/* desc transfer size */
28 #define HSU_CH_D0SAR		0x20			/* desc 0 start addr */
29 #define HSU_CH_D0TSR		0x24			/* desc 0 transfer size */
30 #define HSU_CH_D1SAR		0x28
31 #define HSU_CH_D1TSR		0x2c
32 #define HSU_CH_D2SAR		0x30
33 #define HSU_CH_D2TSR		0x34
34 #define HSU_CH_D3SAR		0x38
35 #define HSU_CH_D3TSR		0x3c
36 
37 #define HSU_DMA_CHAN_NR_DESC	4
38 #define HSU_DMA_CHAN_LENGTH	0x40
39 
40 /* Bits in HSU_CH_SR */
41 #define HSU_CH_SR_DESCTO(x)	BIT(8 + (x))
42 #define HSU_CH_SR_DESCTO_ANY	(BIT(11) | BIT(10) | BIT(9) | BIT(8))
43 #define HSU_CH_SR_CHE		BIT(15)
44 
45 /* Bits in HSU_CH_CR */
46 #define HSU_CH_CR_CHA		BIT(0)
47 #define HSU_CH_CR_CHD		BIT(1)
48 
49 /* Bits in HSU_CH_DCR */
50 #define HSU_CH_DCR_DESCA(x)	BIT(0 + (x))
51 #define HSU_CH_DCR_CHSOD(x)	BIT(8 + (x))
52 #define HSU_CH_DCR_CHSOTO	BIT(14)
53 #define HSU_CH_DCR_CHSOE	BIT(15)
54 #define HSU_CH_DCR_CHDI(x)	BIT(16 + (x))
55 #define HSU_CH_DCR_CHEI		BIT(23)
56 #define HSU_CH_DCR_CHTOI(x)	BIT(24 + (x))
57 
58 struct hsu_dma_sg {
59 	dma_addr_t addr;
60 	unsigned int len;
61 };
62 
63 struct hsu_dma_desc {
64 	struct virt_dma_desc vdesc;
65 	enum dma_transfer_direction direction;
66 	struct hsu_dma_sg *sg;
67 	unsigned int nents;
68 	unsigned int active;
69 	enum dma_status status;
70 };
71 
72 static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
73 {
74 	return container_of(vdesc, struct hsu_dma_desc, vdesc);
75 }
76 
77 struct hsu_dma_chan {
78 	struct virt_dma_chan vchan;
79 
80 	void __iomem *reg;
81 
82 	/* hardware configuration */
83 	enum dma_transfer_direction direction;
84 	struct dma_slave_config config;
85 
86 	struct hsu_dma_desc *desc;
87 };
88 
89 static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
90 {
91 	return container_of(chan, struct hsu_dma_chan, vchan.chan);
92 }
93 
94 static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
95 {
96 	return readl(hsuc->reg + offset);
97 }
98 
99 static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
100 				   u32 value)
101 {
102 	writel(value, hsuc->reg + offset);
103 }
104 
105 struct hsu_dma {
106 	struct dma_device		dma;
107 
108 	/* channels */
109 	struct hsu_dma_chan		*chan;
110 };
111 
112 static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
113 {
114 	return container_of(ddev, struct hsu_dma, dma);
115 }
116 
117 #endif /* __DMA_HSU_H__ */
118