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
6 #include <linux/bitops.h>
7 #include <linux/errno.h>
8 #include <linux/slab.h>
9 #include <linux/types.h>
13 static void dw_dma_initialize_chan(struct dw_dma_chan *dwc)
15 struct dw_dma *dw = to_dw_dma(dwc->chan.device);
16 u32 cfghi = DWC_CFGH_FIFO_MODE;
17 u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
18 bool hs_polarity = dwc->dws.hs_polarity;
20 cfghi |= DWC_CFGH_DST_PER(dwc->dws.dst_id);
21 cfghi |= DWC_CFGH_SRC_PER(dwc->dws.src_id);
22 cfghi |= DWC_CFGH_PROTCTL(dw->pdata->protctl);
24 /* Set polarity of handshake interface */
25 cfglo |= hs_polarity ? DWC_CFGL_HS_DST_POL | DWC_CFGL_HS_SRC_POL : 0;
27 channel_writel(dwc, CFG_LO, cfglo);
28 channel_writel(dwc, CFG_HI, cfghi);
31 static void dw_dma_suspend_chan(struct dw_dma_chan *dwc, bool drain)
33 u32 cfglo = channel_readl(dwc, CFG_LO);
35 channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
38 static void dw_dma_resume_chan(struct dw_dma_chan *dwc, bool drain)
40 u32 cfglo = channel_readl(dwc, CFG_LO);
42 channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
45 static u32 dw_dma_bytes2block(struct dw_dma_chan *dwc,
46 size_t bytes, unsigned int width, size_t *len)
50 if ((bytes >> width) > dwc->block_size) {
51 block = dwc->block_size;
52 *len = dwc->block_size << width;
54 block = bytes >> width;
61 static size_t dw_dma_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
63 return DWC_CTLH_BLOCK_TS(block) << width;
66 static void dw_dma_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst)
69 * Fix burst size according to dw_dmac. We need to convert them as:
70 * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
72 *maxburst = *maxburst > 1 ? fls(*maxburst) - 2 : 0;
75 static void dw_dma_set_device_name(struct dw_dma *dw, int id)
77 snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", id);
80 static void dw_dma_disable(struct dw_dma *dw)
85 static void dw_dma_enable(struct dw_dma *dw)
90 int dw_dma_probe(struct dw_dma_chip *chip)
94 dw = devm_kzalloc(chip->dev, sizeof(*dw), GFP_KERNEL);
98 /* Channel operations */
99 dw->initialize_chan = dw_dma_initialize_chan;
100 dw->suspend_chan = dw_dma_suspend_chan;
101 dw->resume_chan = dw_dma_resume_chan;
102 dw->encode_maxburst = dw_dma_encode_maxburst;
103 dw->bytes2block = dw_dma_bytes2block;
104 dw->block2bytes = dw_dma_block2bytes;
106 /* Device operations */
107 dw->set_device_name = dw_dma_set_device_name;
108 dw->disable = dw_dma_disable;
109 dw->enable = dw_dma_enable;
112 return do_dma_probe(chip);
114 EXPORT_SYMBOL_GPL(dw_dma_probe);
116 int dw_dma_remove(struct dw_dma_chip *chip)
118 return do_dma_remove(chip);
120 EXPORT_SYMBOL_GPL(dw_dma_remove);