xref: /openbmc/linux/drivers/dma/hsu/hsu.h (revision 85250a24)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Driver for the High Speed UART DMA
4  *
5  * Copyright (C) 2015 Intel Corporation
6  *
7  * Partially based on the bits found in drivers/tty/serial/mfd.c.
8  */
9 
10 #ifndef __DMA_HSU_H__
11 #define __DMA_HSU_H__
12 
13 #include <linux/bits.h>
14 #include <linux/container_of.h>
15 #include <linux/io.h>
16 #include <linux/types.h>
17 
18 #include <linux/dma/hsu.h>
19 
20 #include "../virt-dma.h"
21 
22 #define HSU_CH_SR		0x00			/* channel status */
23 #define HSU_CH_CR		0x04			/* channel control */
24 #define HSU_CH_DCR		0x08			/* descriptor control */
25 #define HSU_CH_BSR		0x10			/* FIFO buffer size */
26 #define HSU_CH_MTSR		0x14			/* minimum transfer size */
27 #define HSU_CH_DxSAR(x)		(0x20 + 8 * (x))	/* desc start addr */
28 #define HSU_CH_DxTSR(x)		(0x24 + 8 * (x))	/* desc transfer size */
29 #define HSU_CH_D0SAR		0x20			/* desc 0 start addr */
30 #define HSU_CH_D0TSR		0x24			/* desc 0 transfer size */
31 #define HSU_CH_D1SAR		0x28
32 #define HSU_CH_D1TSR		0x2c
33 #define HSU_CH_D2SAR		0x30
34 #define HSU_CH_D2TSR		0x34
35 #define HSU_CH_D3SAR		0x38
36 #define HSU_CH_D3TSR		0x3c
37 
38 #define HSU_DMA_CHAN_NR_DESC	4
39 #define HSU_DMA_CHAN_LENGTH	0x40
40 
41 /* Bits in HSU_CH_SR */
42 #define HSU_CH_SR_DESCTO(x)	BIT(8 + (x))
43 #define HSU_CH_SR_DESCTO_ANY	GENMASK(11, 8)
44 #define HSU_CH_SR_CHE		BIT(15)
45 #define HSU_CH_SR_DESCE(x)	BIT(16 + (x))
46 #define HSU_CH_SR_DESCE_ANY	GENMASK(19, 16)
47 #define HSU_CH_SR_CDESC_ANY	GENMASK(31, 30)
48 
49 /* Bits in HSU_CH_CR */
50 #define HSU_CH_CR_CHA		BIT(0)
51 #define HSU_CH_CR_CHD		BIT(1)
52 
53 /* Bits in HSU_CH_DCR */
54 #define HSU_CH_DCR_DESCA(x)	BIT(0 + (x))
55 #define HSU_CH_DCR_CHSOD(x)	BIT(8 + (x))
56 #define HSU_CH_DCR_CHSOTO	BIT(14)
57 #define HSU_CH_DCR_CHSOE	BIT(15)
58 #define HSU_CH_DCR_CHDI(x)	BIT(16 + (x))
59 #define HSU_CH_DCR_CHEI		BIT(23)
60 #define HSU_CH_DCR_CHTOI(x)	BIT(24 + (x))
61 
62 /* Bits in HSU_CH_DxTSR */
63 #define HSU_CH_DxTSR_MASK	GENMASK(15, 0)
64 #define HSU_CH_DxTSR_TSR(x)	((x) & HSU_CH_DxTSR_MASK)
65 
66 struct hsu_dma_sg {
67 	dma_addr_t addr;
68 	unsigned int len;
69 };
70 
71 struct hsu_dma_desc {
72 	struct virt_dma_desc vdesc;
73 	enum dma_transfer_direction direction;
74 	struct hsu_dma_sg *sg;
75 	unsigned int nents;
76 	size_t length;
77 	unsigned int active;
78 	enum dma_status status;
79 };
80 
81 static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
82 {
83 	return container_of(vdesc, struct hsu_dma_desc, vdesc);
84 }
85 
86 struct hsu_dma_chan {
87 	struct virt_dma_chan vchan;
88 
89 	void __iomem *reg;
90 
91 	/* hardware configuration */
92 	enum dma_transfer_direction direction;
93 	struct dma_slave_config config;
94 
95 	struct hsu_dma_desc *desc;
96 };
97 
98 static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
99 {
100 	return container_of(chan, struct hsu_dma_chan, vchan.chan);
101 }
102 
103 static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
104 {
105 	return readl(hsuc->reg + offset);
106 }
107 
108 static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
109 				   u32 value)
110 {
111 	writel(value, hsuc->reg + offset);
112 }
113 
114 struct hsu_dma {
115 	struct dma_device		dma;
116 
117 	/* channels */
118 	struct hsu_dma_chan		*chan;
119 	unsigned short			nr_channels;
120 };
121 
122 static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
123 {
124 	return container_of(ddev, struct hsu_dma, dma);
125 }
126 
127 #endif /* __DMA_HSU_H__ */
128