xref: /openbmc/linux/drivers/dma/hsu/hsu.h (revision e3d786a3)
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 #define HSU_CH_SR_DESCE(x)	BIT(16 + (x))
45 #define HSU_CH_SR_DESCE_ANY	(BIT(19) | BIT(18) | BIT(17) | BIT(16))
46 #define HSU_CH_SR_CDESC_ANY	(BIT(31) | BIT(30))
47 
48 /* Bits in HSU_CH_CR */
49 #define HSU_CH_CR_CHA		BIT(0)
50 #define HSU_CH_CR_CHD		BIT(1)
51 
52 /* Bits in HSU_CH_DCR */
53 #define HSU_CH_DCR_DESCA(x)	BIT(0 + (x))
54 #define HSU_CH_DCR_CHSOD(x)	BIT(8 + (x))
55 #define HSU_CH_DCR_CHSOTO	BIT(14)
56 #define HSU_CH_DCR_CHSOE	BIT(15)
57 #define HSU_CH_DCR_CHDI(x)	BIT(16 + (x))
58 #define HSU_CH_DCR_CHEI		BIT(23)
59 #define HSU_CH_DCR_CHTOI(x)	BIT(24 + (x))
60 
61 /* Bits in HSU_CH_DxTSR */
62 #define HSU_CH_DxTSR_MASK	GENMASK(15, 0)
63 #define HSU_CH_DxTSR_TSR(x)	((x) & HSU_CH_DxTSR_MASK)
64 
65 struct hsu_dma_sg {
66 	dma_addr_t addr;
67 	unsigned int len;
68 };
69 
70 struct hsu_dma_desc {
71 	struct virt_dma_desc vdesc;
72 	enum dma_transfer_direction direction;
73 	struct hsu_dma_sg *sg;
74 	unsigned int nents;
75 	size_t length;
76 	unsigned int active;
77 	enum dma_status status;
78 };
79 
80 static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
81 {
82 	return container_of(vdesc, struct hsu_dma_desc, vdesc);
83 }
84 
85 struct hsu_dma_chan {
86 	struct virt_dma_chan vchan;
87 
88 	void __iomem *reg;
89 
90 	/* hardware configuration */
91 	enum dma_transfer_direction direction;
92 	struct dma_slave_config config;
93 
94 	struct hsu_dma_desc *desc;
95 };
96 
97 static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
98 {
99 	return container_of(chan, struct hsu_dma_chan, vchan.chan);
100 }
101 
102 static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
103 {
104 	return readl(hsuc->reg + offset);
105 }
106 
107 static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
108 				   u32 value)
109 {
110 	writel(value, hsuc->reg + offset);
111 }
112 
113 struct hsu_dma {
114 	struct dma_device		dma;
115 
116 	/* channels */
117 	struct hsu_dma_chan		*chan;
118 	unsigned short			nr_channels;
119 };
120 
121 static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
122 {
123 	return container_of(ddev, struct hsu_dma, dma);
124 }
125 
126 #endif /* __DMA_HSU_H__ */
127