1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2007-2008 Atmel Corporation
3 // Copyright (C) 2010-2011 ST Microelectronics
4 // Copyright (C) 2013,2018 Intel Corporation
5
6 #include <linux/bitops.h>
7 #include <linux/dmaengine.h>
8 #include <linux/errno.h>
9 #include <linux/slab.h>
10 #include <linux/types.h>
11
12 #include "internal.h"
13
dw_dma_initialize_chan(struct dw_dma_chan * dwc)14 static void dw_dma_initialize_chan(struct dw_dma_chan *dwc)
15 {
16 struct dw_dma *dw = to_dw_dma(dwc->chan.device);
17 u32 cfghi = is_slave_direction(dwc->direction) ? 0 : DWC_CFGH_FIFO_MODE;
18 u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
19 bool hs_polarity = dwc->dws.hs_polarity;
20
21 cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
22 cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
23 cfghi |= DWC_CFGH_PROTCTL(dw->pdata->protctl);
24
25 /* Set polarity of handshake interface */
26 cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0;
27
28 channel_writel(dwc, CFG_LO, cfglo);
29 channel_writel(dwc, CFG_HI, cfghi);
30 }
31
dw_dma_suspend_chan(struct dw_dma_chan * dwc,bool drain)32 static void dw_dma_suspend_chan(struct dw_dma_chan *dwc, bool drain)
33 {
34 u32 cfglo = channel_readl(dwc, CFG_LO);
35
36 channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
37 }
38
dw_dma_resume_chan(struct dw_dma_chan * dwc,bool drain)39 static void dw_dma_resume_chan(struct dw_dma_chan *dwc, bool drain)
40 {
41 u32 cfglo = channel_readl(dwc, CFG_LO);
42
43 channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
44 }
45
dw_dma_bytes2block(struct dw_dma_chan * dwc,size_t bytes,unsigned int width,size_t * len)46 static u32 dw_dma_bytes2block(struct dw_dma_chan *dwc,
47 size_t bytes, unsigned int width, size_t *len)
48 {
49 u32 block;
50
51 if ((bytes >> width) > dwc->block_size) {
52 block = dwc->block_size;
53 *len = dwc->block_size << width;
54 } else {
55 block = bytes >> width;
56 *len = bytes;
57 }
58
59 return block;
60 }
61
dw_dma_block2bytes(struct dw_dma_chan * dwc,u32 block,u32 width)62 static size_t dw_dma_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
63 {
64 return DWC_CTLH_BLOCK_TS(block) << width;
65 }
66
dw_dma_prepare_ctllo(struct dw_dma_chan * dwc)67 static u32 dw_dma_prepare_ctllo(struct dw_dma_chan *dwc)
68 {
69 struct dma_slave_config *sconfig = &dwc->dma_sconfig;
70 u8 smsize = (dwc->direction == DMA_DEV_TO_MEM) ? sconfig->src_maxburst : 0;
71 u8 dmsize = (dwc->direction == DMA_MEM_TO_DEV) ? sconfig->dst_maxburst : 0;
72 u8 p_master = dwc->dws.p_master;
73 u8 m_master = dwc->dws.m_master;
74 u8 dms = (dwc->direction == DMA_MEM_TO_DEV) ? p_master : m_master;
75 u8 sms = (dwc->direction == DMA_DEV_TO_MEM) ? p_master : m_master;
76
77 return DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN |
78 DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize) |
79 DWC_CTLL_DMS(dms) | DWC_CTLL_SMS(sms);
80 }
81
dw_dma_encode_maxburst(struct dw_dma_chan * dwc,u32 * maxburst)82 static void dw_dma_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
83 {
84 /*
85 * Fix burst size according to dw_dmac. We need to convert them as:
86 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
87 */
88 *maxburst = *maxburst > 1 ? fls(*maxburst) - 2 : 0;
89 }
90
dw_dma_set_device_name(struct dw_dma * dw,int id)91 static void dw_dma_set_device_name(struct dw_dma *dw, int id)
92 {
93 snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", id);
94 }
95
dw_dma_disable(struct dw_dma * dw)96 static void dw_dma_disable(struct dw_dma *dw)
97 {
98 do_dw_dma_off(dw);
99 }
100
dw_dma_enable(struct dw_dma * dw)101 static void dw_dma_enable(struct dw_dma *dw)
102 {
103 do_dw_dma_on(dw);
104 }
105
dw_dma_probe(struct dw_dma_chip * chip)106 int dw_dma_probe(struct dw_dma_chip *chip)
107 {
108 struct dw_dma *dw;
109
110 dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
111 if (!dw)
112 return -ENOMEM;
113
114 /* Channel operations */
115 dw->initialize_chan = dw_dma_initialize_chan;
116 dw->suspend_chan = dw_dma_suspend_chan;
117 dw->resume_chan = dw_dma_resume_chan;
118 dw->prepare_ctllo = dw_dma_prepare_ctllo;
119 dw->encode_maxburst = dw_dma_encode_maxburst;
120 dw->bytes2block = dw_dma_bytes2block;
121 dw->block2bytes = dw_dma_block2bytes;
122
123 /* Device operations */
124 dw->set_device_name = dw_dma_set_device_name;
125 dw->disable = dw_dma_disable;
126 dw->enable = dw_dma_enable;
127
128 chip->dw = dw;
129 return do_dma_probe(chip);
130 }
131 EXPORT_SYMBOL_GPL(dw_dma_probe);
132
dw_dma_remove(struct dw_dma_chip * chip)133 int dw_dma_remove(struct dw_dma_chip *chip)
134 {
135 return do_dma_remove(chip);
136 }
137 EXPORT_SYMBOL_GPL(dw_dma_remove);
138