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 struct hsu_dma_sg {
62 	dma_addr_t addr;
63 	unsigned int len;
64 };
65 
66 struct hsu_dma_desc {
67 	struct virt_dma_desc vdesc;
68 	enum dma_transfer_direction direction;
69 	struct hsu_dma_sg *sg;
70 	unsigned int nents;
71 	unsigned int active;
72 	enum dma_status status;
73 };
74 
to_hsu_dma_desc(struct virt_dma_desc * vdesc)75 static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc)
76 {
77 	return container_of(vdesc, struct hsu_dma_desc, vdesc);
78 }
79 
80 struct hsu_dma_chan {
81 	struct virt_dma_chan vchan;
82 
83 	void __iomem *reg;
84 
85 	/* hardware configuration */
86 	enum dma_transfer_direction direction;
87 	struct dma_slave_config config;
88 
89 	struct hsu_dma_desc *desc;
90 };
91 
to_hsu_dma_chan(struct dma_chan * chan)92 static inline struct hsu_dma_chan *to_hsu_dma_chan(struct dma_chan *chan)
93 {
94 	return container_of(chan, struct hsu_dma_chan, vchan.chan);
95 }
96 
hsu_chan_readl(struct hsu_dma_chan * hsuc,int offset)97 static inline u32 hsu_chan_readl(struct hsu_dma_chan *hsuc, int offset)
98 {
99 	return readl(hsuc->reg + offset);
100 }
101 
hsu_chan_writel(struct hsu_dma_chan * hsuc,int offset,u32 value)102 static inline void hsu_chan_writel(struct hsu_dma_chan *hsuc, int offset,
103 				   u32 value)
104 {
105 	writel(value, hsuc->reg + offset);
106 }
107 
108 struct hsu_dma {
109 	struct dma_device		dma;
110 
111 	/* channels */
112 	struct hsu_dma_chan		*chan;
113 	unsigned short			nr_channels;
114 };
115 
to_hsu_dma(struct dma_device * ddev)116 static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev)
117 {
118 	return container_of(ddev, struct hsu_dma, dma);
119 }
120 
121 #endif /* __DMA_HSU_H__ */
122