1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2013,2018,2020-2021 Intel Corporation
3
4#include <linux/bitops.h>
5#include <linux/dmaengine.h>
6#include <linux/errno.h>
7#include <linux/io.h>
8#include <linux/pci.h>
9#include <linux/slab.h>
10#include <linux/types.h>
11
12#include "internal.h"
13
14#define DMA_CTL_CH(x) (0x1000 + (x) * 4)
15#define DMA_SRC_ADDR_FILLIN(x) (0x1100 + (x) * 4)
16#define DMA_DST_ADDR_FILLIN(x) (0x1200 + (x) * 4)
17#define DMA_XBAR_SEL(x) (0x1300 + (x) * 4)
18#define DMA_REGACCESS_CHID_CFG (0x1400)
19
20#define CTL_CH_TRANSFER_MODE_MASK GENMASK(1, 0)
21#define CTL_CH_TRANSFER_MODE_S2S 0
22#define CTL_CH_TRANSFER_MODE_S2D 1
23#define CTL_CH_TRANSFER_MODE_D2S 2
24#define CTL_CH_TRANSFER_MODE_D2D 3
25#define CTL_CH_RD_RS_MASK GENMASK(4, 3)
26#define CTL_CH_WR_RS_MASK GENMASK(6, 5)
27#define CTL_CH_RD_NON_SNOOP_BIT BIT(8)
28#define CTL_CH_WR_NON_SNOOP_BIT BIT(9)
29
30#define XBAR_SEL_DEVID_MASK GENMASK(15, 0)
31#define XBAR_SEL_RX_TX_BIT BIT(16)
32#define XBAR_SEL_RX_TX_SHIFT 16
33
34#define REGACCESS_CHID_MASK GENMASK(2, 0)
35
36static unsigned int idma32_get_slave_devfn(struct dw_dma_chan *dwc)
37{
38 struct device *slave = dwc->chan.slave;
39
40 if (!slave || !dev_is_pci(slave))
41 return 0;
42
43 return to_pci_dev(slave)->devfn;
44}
45
46static void idma32_initialize_chan_xbar(struct dw_dma_chan *dwc)
47{
48 struct dw_dma *dw = to_dw_dma(ddev: dwc->chan.device);
49 void __iomem *misc = __dw_regs(dw);
50 u32 cfghi = 0, cfglo = 0;
51 u8 dst_id, src_id;
52 u32 value;
53
54 /* DMA Channel ID Configuration register must be programmed first */
55 value = readl(addr: misc + DMA_REGACCESS_CHID_CFG);
56
57 value &= ~REGACCESS_CHID_MASK;
58 value |= dwc->chan.chan_id;
59
60 writel(val: value, addr: misc + DMA_REGACCESS_CHID_CFG);
61
62 /* Configure channel attributes */
63 value = readl(addr: misc + DMA_CTL_CH(dwc->chan.chan_id));
64
65 value &= ~(CTL_CH_RD_NON_SNOOP_BIT | CTL_CH_WR_NON_SNOOP_BIT);
66 value &= ~(CTL_CH_RD_RS_MASK | CTL_CH_WR_RS_MASK);
67 value &= ~CTL_CH_TRANSFER_MODE_MASK;
68
69 switch (dwc->direction) {
70 case DMA_MEM_TO_DEV:
71 value |= CTL_CH_TRANSFER_MODE_D2S;
72 value |= CTL_CH_WR_NON_SNOOP_BIT;
73 break;
74 case DMA_DEV_TO_MEM:
75 value |= CTL_CH_TRANSFER_MODE_S2D;
76 value |= CTL_CH_RD_NON_SNOOP_BIT;
77 break;
78 default:
79 /*
80 * Memory-to-Memory and Device-to-Device are ignored for now.
81 *
82 * For Memory-to-Memory transfers we would need to set mode
83 * and disable snooping on both sides.
84 */
85 return;
86 }
87
88 writel(val: value, addr: misc + DMA_CTL_CH(dwc->chan.chan_id));
89
90 /* Configure crossbar selection */
91 value = readl(addr: misc + DMA_XBAR_SEL(dwc->chan.chan_id));
92
93 /* DEVFN selection */
94 value &= ~XBAR_SEL_DEVID_MASK;
95 value |= idma32_get_slave_devfn(dwc);
96
97 switch (dwc->direction) {
98 case DMA_MEM_TO_DEV:
99 value |= XBAR_SEL_RX_TX_BIT;
100 break;
101 case DMA_DEV_TO_MEM:
102 value &= ~XBAR_SEL_RX_TX_BIT;
103 break;
104 default:
105 /* Memory-to-Memory and Device-to-Device are ignored for now */
106 return;
107 }
108
109 writel(val: value, addr: misc + DMA_XBAR_SEL(dwc->chan.chan_id));
110
111 /* Configure DMA channel low and high registers */
112 switch (dwc->direction) {
113 case DMA_MEM_TO_DEV:
114 dst_id = dwc->chan.chan_id;
115 src_id = dwc->dws.src_id;
116 break;
117 case DMA_DEV_TO_MEM:
118 dst_id = dwc->dws.dst_id;
119 src_id = dwc->chan.chan_id;
120 break;
121 default:
122 /* Memory-to-Memory and Device-to-Device are ignored for now */
123 return;
124 }
125
126 /* Set default burst alignment */
127 cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
128
129 /* Low 4 bits of the request lines */
130 cfghi |= IDMA32C_CFGH_DST_PER(dst_id & 0xf);
131 cfghi |= IDMA32C_CFGH_SRC_PER(src_id & 0xf);
132
133 /* Request line extension (2 bits) */
134 cfghi |= IDMA32C_CFGH_DST_PER_EXT(dst_id >> 4 & 0x3);
135 cfghi |= IDMA32C_CFGH_SRC_PER_EXT(src_id >> 4 & 0x3);
136
137 channel_writel(dwc, CFG_LO, cfglo);
138 channel_writel(dwc, CFG_HI, cfghi);
139}
140
141static void idma32_initialize_chan_generic(struct dw_dma_chan *dwc)
142{
143 u32 cfghi = 0;
144 u32 cfglo = 0;
145
146 /* Set default burst alignment */
147 cfglo |= IDMA32C_CFGL_DST_BURST_ALIGN | IDMA32C_CFGL_SRC_BURST_ALIGN;
148
149 /* Low 4 bits of the request lines */
150 cfghi |= IDMA32C_CFGH_DST_PER(dwc->dws.dst_id & 0xf);
151 cfghi |= IDMA32C_CFGH_SRC_PER(dwc->dws.src_id & 0xf);
152
153 /* Request line extension (2 bits) */
154 cfghi |= IDMA32C_CFGH_DST_PER_EXT(dwc->dws.dst_id >> 4 & 0x3);
155 cfghi |= IDMA32C_CFGH_SRC_PER_EXT(dwc->dws.src_id >> 4 & 0x3);
156
157 channel_writel(dwc, CFG_LO, cfglo);
158 channel_writel(dwc, CFG_HI, cfghi);
159}
160
161static void idma32_suspend_chan(struct dw_dma_chan *dwc, bool drain)
162{
163 u32 cfglo = channel_readl(dwc, CFG_LO);
164
165 if (drain)
166 cfglo |= IDMA32C_CFGL_CH_DRAIN;
167
168 channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
169}
170
171static void idma32_resume_chan(struct dw_dma_chan *dwc, bool drain)
172{
173 u32 cfglo = channel_readl(dwc, CFG_LO);
174
175 if (drain)
176 cfglo &= ~IDMA32C_CFGL_CH_DRAIN;
177
178 channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
179}
180
181static u32 idma32_bytes2block(struct dw_dma_chan *dwc,
182 size_t bytes, unsigned int width, size_t *len)
183{
184 u32 block;
185
186 if (bytes > dwc->block_size) {
187 block = dwc->block_size;
188 *len = dwc->block_size;
189 } else {
190 block = bytes;
191 *len = bytes;
192 }
193
194 return block;
195}
196
197static size_t idma32_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width)
198{
199 return IDMA32C_CTLH_BLOCK_TS(block);
200}
201
202static inline u8 idma32_encode_maxburst(u32 maxburst)
203{
204 return maxburst > 1 ? fls(x: maxburst) - 1 : 0;
205}
206
207static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc)
208{
209 struct dma_slave_config *sconfig = &dwc->dma_sconfig;
210 u8 smsize = 0, dmsize = 0;
211
212 if (dwc->direction == DMA_MEM_TO_DEV)
213 dmsize = idma32_encode_maxburst(maxburst: sconfig->dst_maxburst);
214 else if (dwc->direction == DMA_DEV_TO_MEM)
215 smsize = idma32_encode_maxburst(maxburst: sconfig->src_maxburst);
216
217 return DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN |
218 DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize);
219}
220
221static void idma32_set_device_name(struct dw_dma *dw, int id)
222{
223 snprintf(buf: dw->name, size: sizeof(dw->name), fmt: "idma32:dmac%d", id);
224}
225
226/*
227 * Program FIFO size of channels.
228 *
229 * By default full FIFO (512 bytes) is assigned to channel 0. Here we
230 * slice FIFO on equal parts between channels.
231 */
232static void idma32_fifo_partition(struct dw_dma *dw)
233{
234 u64 value = IDMA32C_FP_PSIZE_CH0(64) | IDMA32C_FP_PSIZE_CH1(64) |
235 IDMA32C_FP_UPDATE;
236 u64 fifo_partition = 0;
237
238 /* Fill FIFO_PARTITION low bits (Channels 0..1, 4..5) */
239 fifo_partition |= value << 0;
240
241 /* Fill FIFO_PARTITION high bits (Channels 2..3, 6..7) */
242 fifo_partition |= value << 32;
243
244 /* Program FIFO Partition registers - 64 bytes per channel */
245 idma32_writeq(dw, FIFO_PARTITION1, fifo_partition);
246 idma32_writeq(dw, FIFO_PARTITION0, fifo_partition);
247}
248
249static void idma32_disable(struct dw_dma *dw)
250{
251 do_dw_dma_off(dw);
252 idma32_fifo_partition(dw);
253}
254
255static void idma32_enable(struct dw_dma *dw)
256{
257 idma32_fifo_partition(dw);
258 do_dw_dma_on(dw);
259}
260
261int idma32_dma_probe(struct dw_dma_chip *chip)
262{
263 struct dw_dma *dw;
264
265 dw = devm_kzalloc(dev: chip->dev, size: sizeof(*dw), GFP_KERNEL);
266 if (!dw)
267 return -ENOMEM;
268
269 /* Channel operations */
270 if (chip->pdata->quirks & DW_DMA_QUIRK_XBAR_PRESENT)
271 dw->initialize_chan = idma32_initialize_chan_xbar;
272 else
273 dw->initialize_chan = idma32_initialize_chan_generic;
274 dw->suspend_chan = idma32_suspend_chan;
275 dw->resume_chan = idma32_resume_chan;
276 dw->prepare_ctllo = idma32_prepare_ctllo;
277 dw->bytes2block = idma32_bytes2block;
278 dw->block2bytes = idma32_block2bytes;
279
280 /* Device operations */
281 dw->set_device_name = idma32_set_device_name;
282 dw->disable = idma32_disable;
283 dw->enable = idma32_enable;
284
285 chip->dw = dw;
286 return do_dma_probe(chip);
287}
288EXPORT_SYMBOL_GPL(idma32_dma_probe);
289
290int idma32_dma_remove(struct dw_dma_chip *chip)
291{
292 return do_dma_remove(chip);
293}
294EXPORT_SYMBOL_GPL(idma32_dma_remove);
295