xref: /openbmc/linux/drivers/dma/hsu/hsu.h (revision d9fd5a71)
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/spinlock.h>
14 #include <linux/dma/hsu.h>
15 
16 #include "../virt-dma.h"
17 
18 #define HSU_CH_SR		0x00			/* channel status */
19 #define HSU_CH_CR		0x04			/* channel control */
20 #define HSU_CH_DCR		0x08			/* descriptor control */
21 #define HSU_CH_BSR		0x10			/* FIFO buffer size */
22 #define HSU_CH_MTSR		0x14			/* minimum transfer size */
23 #define HSU_CH_DxSAR(x)		(0x20 + 8 * (x))	/* desc start addr */
24 #define HSU_CH_DxTSR(x)		(0x24 + 8 * (x))	/* desc transfer size */
25 #define HSU_CH_D0SAR		0x20			/* desc 0 start addr */
26 #define HSU_CH_D0TSR		0x24			/* desc 0 transfer size */
27 #define HSU_CH_D1SAR		0x28
28 #define HSU_CH_D1TSR		0x2c
29 #define HSU_CH_D2SAR		0x30
30 #define HSU_CH_D2TSR		0x34
31 #define HSU_CH_D3SAR		0x38
32 #define HSU_CH_D3TSR		0x3c
33 
34 #define HSU_DMA_CHAN_NR_DESC	4
35 #define HSU_DMA_CHAN_LENGTH	0x40
36 
37 /* Bits in HSU_CH_SR */
38 #define HSU_CH_SR_DESCTO(x)	BIT(8 + (x))
39 #define HSU_CH_SR_DESCTO_ANY	(BIT(11) | BIT(10) | BIT(9) | BIT(8))
40 #define HSU_CH_SR_CHE		BIT(15)
41 #define HSU_CH_SR_DESCE(x)	BIT(16 + (x))
42 #define HSU_CH_SR_DESCE_ANY	(BIT(19) | BIT(18) | BIT(17) | BIT(16))
43 #define HSU_CH_SR_CDESC_ANY	(BIT(31) | BIT(30))
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 /* Bits in HSU_CH_DxTSR */
59 #define HSU_CH_DxTSR_MASK	GENMASK(15, 0)
60 #define HSU_CH_DxTSR_TSR(x)	((x) & HSU_CH_DxTSR_MASK)
61 
62 struct hsu_dma_sg {
63 	dma_addr_t addr;
64 	unsigned int len;
65 };
66 
67 struct hsu_dma_desc {
68 	struct virt_dma_desc vdesc;
69 	enum dma_transfer_direction direction;
70 	struct hsu_dma_sg *sg;
71 	unsigned int nents;
72 	size_t length;
73 	unsigned int active;
74 	enum dma_status status;
75 };
76 
77 static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
78 {
79 	return container_of(vdesc, struct hsu_dma_desc, vdesc);
80 }
81 
82 struct hsu_dma_chan {
83 	struct virt_dma_chan vchan;
84 
85 	void __iomem *reg;
86 
87 	/* hardware configuration */
88 	enum dma_transfer_direction direction;
89 	struct dma_slave_config config;
90 
91 	struct hsu_dma_desc *desc;
92 };
93 
94 static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
95 {
96 	return container_of(chan, struct hsu_dma_chan, vchan.chan);
97 }
98 
99 static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
100 {
101 	return readl(hsuc->reg + offset);
102 }
103 
104 static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
105 				   u32 value)
106 {
107 	writel(value, hsuc->reg + offset);
108 }
109 
110 struct hsu_dma {
111 	struct dma_device		dma;
112 
113 	/* channels */
114 	struct hsu_dma_chan		*chan;
115 	unsigned short			nr_channels;
116 };
117 
118 static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
119 {
120 	return container_of(ddev, struct hsu_dma, dma);
121 }
122 
123 #endif /* __DMA_HSU_H__ */
124