1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2022 Schneider-Electric |
4 | * Author: Miquel Raynal <miquel.raynal@bootlin.com |
5 | * Based on TI crossbar driver written by Peter Ujfalusi <peter.ujfalusi@ti.com> |
6 | */ |
7 | #include <linux/bitops.h> |
8 | #include <linux/of.h> |
9 | #include <linux/of_dma.h> |
10 | #include <linux/of_platform.h> |
11 | #include <linux/platform_device.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/soc/renesas/r9a06g032-sysctrl.h> |
14 | #include <linux/types.h> |
15 | |
16 | #define RNZ1_DMAMUX_NCELLS 6 |
17 | #define RZN1_DMAMUX_MAX_LINES 64 |
18 | #define RZN1_DMAMUX_LINES_PER_CTLR 16 |
19 | |
20 | struct rzn1_dmamux_data { |
21 | struct dma_router dmarouter; |
22 | DECLARE_BITMAP(used_chans, 2 * RZN1_DMAMUX_LINES_PER_CTLR); |
23 | }; |
24 | |
25 | struct rzn1_dmamux_map { |
26 | unsigned int req_idx; |
27 | }; |
28 | |
29 | static void rzn1_dmamux_free(struct device *dev, void *route_data) |
30 | { |
31 | struct rzn1_dmamux_data *dmamux = dev_get_drvdata(dev); |
32 | struct rzn1_dmamux_map *map = route_data; |
33 | |
34 | dev_dbg(dev, "Unmapping DMAMUX request %u\n" , map->req_idx); |
35 | |
36 | clear_bit(nr: map->req_idx, addr: dmamux->used_chans); |
37 | |
38 | kfree(objp: map); |
39 | } |
40 | |
41 | static void *rzn1_dmamux_route_allocate(struct of_phandle_args *dma_spec, |
42 | struct of_dma *ofdma) |
43 | { |
44 | struct platform_device *pdev = of_find_device_by_node(np: ofdma->of_node); |
45 | struct rzn1_dmamux_data *dmamux = platform_get_drvdata(pdev); |
46 | struct rzn1_dmamux_map *map; |
47 | unsigned int dmac_idx, chan, val; |
48 | u32 mask; |
49 | int ret; |
50 | |
51 | if (dma_spec->args_count != RNZ1_DMAMUX_NCELLS) |
52 | return ERR_PTR(error: -EINVAL); |
53 | |
54 | map = kzalloc(size: sizeof(*map), GFP_KERNEL); |
55 | if (!map) |
56 | return ERR_PTR(error: -ENOMEM); |
57 | |
58 | chan = dma_spec->args[0]; |
59 | map->req_idx = dma_spec->args[4]; |
60 | val = dma_spec->args[5]; |
61 | dma_spec->args_count -= 2; |
62 | |
63 | if (chan >= RZN1_DMAMUX_LINES_PER_CTLR) { |
64 | dev_err(&pdev->dev, "Invalid DMA request line: %u\n" , chan); |
65 | ret = -EINVAL; |
66 | goto free_map; |
67 | } |
68 | |
69 | if (map->req_idx >= RZN1_DMAMUX_MAX_LINES || |
70 | (map->req_idx % RZN1_DMAMUX_LINES_PER_CTLR) != chan) { |
71 | dev_err(&pdev->dev, "Invalid MUX request line: %u\n" , map->req_idx); |
72 | ret = -EINVAL; |
73 | goto free_map; |
74 | } |
75 | |
76 | dmac_idx = map->req_idx >= RZN1_DMAMUX_LINES_PER_CTLR ? 1 : 0; |
77 | dma_spec->np = of_parse_phandle(np: ofdma->of_node, phandle_name: "dma-masters" , index: dmac_idx); |
78 | if (!dma_spec->np) { |
79 | dev_err(&pdev->dev, "Can't get DMA master\n" ); |
80 | ret = -EINVAL; |
81 | goto free_map; |
82 | } |
83 | |
84 | dev_dbg(&pdev->dev, "Mapping DMAMUX request %u to DMAC%u request %u\n" , |
85 | map->req_idx, dmac_idx, chan); |
86 | |
87 | if (test_and_set_bit(nr: map->req_idx, addr: dmamux->used_chans)) { |
88 | ret = -EBUSY; |
89 | goto free_map; |
90 | } |
91 | |
92 | mask = BIT(map->req_idx); |
93 | ret = r9a06g032_sysctrl_set_dmamux(mask, val: val ? mask : 0); |
94 | if (ret) |
95 | goto clear_bitmap; |
96 | |
97 | return map; |
98 | |
99 | clear_bitmap: |
100 | clear_bit(nr: map->req_idx, addr: dmamux->used_chans); |
101 | free_map: |
102 | kfree(objp: map); |
103 | |
104 | return ERR_PTR(error: ret); |
105 | } |
106 | |
107 | #ifdef CONFIG_OF |
108 | static const struct of_device_id rzn1_dmac_match[] = { |
109 | { .compatible = "renesas,rzn1-dma" }, |
110 | {} |
111 | }; |
112 | #endif |
113 | |
114 | static int rzn1_dmamux_probe(struct platform_device *pdev) |
115 | { |
116 | struct device_node *mux_node = pdev->dev.of_node; |
117 | const struct of_device_id *match; |
118 | struct device_node *dmac_node; |
119 | struct rzn1_dmamux_data *dmamux; |
120 | |
121 | dmamux = devm_kzalloc(dev: &pdev->dev, size: sizeof(*dmamux), GFP_KERNEL); |
122 | if (!dmamux) |
123 | return -ENOMEM; |
124 | |
125 | dmac_node = of_parse_phandle(np: mux_node, phandle_name: "dma-masters" , index: 0); |
126 | if (!dmac_node) |
127 | return dev_err_probe(dev: &pdev->dev, err: -ENODEV, fmt: "Can't get DMA master node\n" ); |
128 | |
129 | match = of_match_node(matches: rzn1_dmac_match, node: dmac_node); |
130 | of_node_put(node: dmac_node); |
131 | if (!match) |
132 | return dev_err_probe(dev: &pdev->dev, err: -EINVAL, fmt: "DMA master is not supported\n" ); |
133 | |
134 | dmamux->dmarouter.dev = &pdev->dev; |
135 | dmamux->dmarouter.route_free = rzn1_dmamux_free; |
136 | |
137 | platform_set_drvdata(pdev, data: dmamux); |
138 | |
139 | return of_dma_router_register(np: mux_node, of_dma_route_allocate: rzn1_dmamux_route_allocate, |
140 | dma_router: &dmamux->dmarouter); |
141 | } |
142 | |
143 | static const struct of_device_id rzn1_dmamux_match[] = { |
144 | { .compatible = "renesas,rzn1-dmamux" }, |
145 | {} |
146 | }; |
147 | MODULE_DEVICE_TABLE(of, rzn1_dmamux_match); |
148 | |
149 | static struct platform_driver rzn1_dmamux_driver = { |
150 | .driver = { |
151 | .name = "renesas,rzn1-dmamux" , |
152 | .of_match_table = rzn1_dmamux_match, |
153 | }, |
154 | .probe = rzn1_dmamux_probe, |
155 | }; |
156 | module_platform_driver(rzn1_dmamux_driver); |
157 | |
158 | MODULE_LICENSE("GPL" ); |
159 | MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com" ); |
160 | MODULE_DESCRIPTION("Renesas RZ/N1 DMAMUX driver" ); |
161 | |