1 | // SPDX-License-Identifier: GPL-2.0 |
2 | // |
3 | // Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com/ |
4 | // Author: Vignesh Raghavendra <vigneshr@ti.com> |
5 | |
6 | #include <linux/completion.h> |
7 | #include <linux/dma-direction.h> |
8 | #include <linux/dma-mapping.h> |
9 | #include <linux/dmaengine.h> |
10 | #include <linux/err.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/module.h> |
13 | #include <linux/mtd/cfi.h> |
14 | #include <linux/mtd/hyperbus.h> |
15 | #include <linux/mtd/mtd.h> |
16 | #include <linux/mux/consumer.h> |
17 | #include <linux/of.h> |
18 | #include <linux/of_address.h> |
19 | #include <linux/platform_device.h> |
20 | #include <linux/sched/task_stack.h> |
21 | #include <linux/types.h> |
22 | |
23 | #define AM654_HBMC_CALIB_COUNT 25 |
24 | |
25 | struct am654_hbmc_device_priv { |
26 | struct completion rx_dma_complete; |
27 | phys_addr_t device_base; |
28 | struct hyperbus_ctlr *ctlr; |
29 | struct dma_chan *rx_chan; |
30 | }; |
31 | |
32 | struct am654_hbmc_priv { |
33 | struct hyperbus_ctlr ctlr; |
34 | struct hyperbus_device hbdev; |
35 | struct mux_control *mux_ctrl; |
36 | }; |
37 | |
38 | static int am654_hbmc_calibrate(struct hyperbus_device *hbdev) |
39 | { |
40 | struct map_info *map = &hbdev->map; |
41 | struct cfi_private cfi; |
42 | int count = AM654_HBMC_CALIB_COUNT; |
43 | int pass_count = 0; |
44 | int ret; |
45 | |
46 | cfi.interleave = 1; |
47 | cfi.device_type = CFI_DEVICETYPE_X16; |
48 | cfi_send_gen_cmd(cmd: 0xF0, cmd_addr: 0, base: 0, map, cfi: &cfi, type: cfi.device_type, NULL); |
49 | cfi_send_gen_cmd(cmd: 0x98, cmd_addr: 0x55, base: 0, map, cfi: &cfi, type: cfi.device_type, NULL); |
50 | |
51 | while (count--) { |
52 | ret = cfi_qry_present(map, base: 0, cfi: &cfi); |
53 | if (ret) |
54 | pass_count++; |
55 | else |
56 | pass_count = 0; |
57 | if (pass_count == 5) |
58 | break; |
59 | } |
60 | |
61 | cfi_qry_mode_off(base: 0, map, cfi: &cfi); |
62 | |
63 | return ret; |
64 | } |
65 | |
66 | static void am654_hbmc_dma_callback(void *param) |
67 | { |
68 | struct am654_hbmc_device_priv *priv = param; |
69 | |
70 | complete(&priv->rx_dma_complete); |
71 | } |
72 | |
73 | static int am654_hbmc_dma_read(struct am654_hbmc_device_priv *priv, void *to, |
74 | unsigned long from, ssize_t len) |
75 | |
76 | { |
77 | enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT; |
78 | struct dma_chan *rx_chan = priv->rx_chan; |
79 | struct dma_async_tx_descriptor *tx; |
80 | dma_addr_t dma_dst, dma_src; |
81 | dma_cookie_t cookie; |
82 | int ret; |
83 | |
84 | if (!priv->rx_chan || !virt_addr_valid(to) || object_is_on_stack(obj: to)) |
85 | return -EINVAL; |
86 | |
87 | dma_dst = dma_map_single(rx_chan->device->dev, to, len, DMA_FROM_DEVICE); |
88 | if (dma_mapping_error(dev: rx_chan->device->dev, dma_addr: dma_dst)) { |
89 | dev_dbg(priv->ctlr->dev, "DMA mapping failed\n" ); |
90 | return -EIO; |
91 | } |
92 | |
93 | dma_src = priv->device_base + from; |
94 | tx = dmaengine_prep_dma_memcpy(chan: rx_chan, dest: dma_dst, src: dma_src, len, flags); |
95 | if (!tx) { |
96 | dev_err(priv->ctlr->dev, "device_prep_dma_memcpy error\n" ); |
97 | ret = -EIO; |
98 | goto unmap_dma; |
99 | } |
100 | |
101 | reinit_completion(x: &priv->rx_dma_complete); |
102 | tx->callback = am654_hbmc_dma_callback; |
103 | tx->callback_param = priv; |
104 | cookie = dmaengine_submit(desc: tx); |
105 | |
106 | ret = dma_submit_error(cookie); |
107 | if (ret) { |
108 | dev_err(priv->ctlr->dev, "dma_submit_error %d\n" , cookie); |
109 | goto unmap_dma; |
110 | } |
111 | |
112 | dma_async_issue_pending(chan: rx_chan); |
113 | if (!wait_for_completion_timeout(x: &priv->rx_dma_complete, timeout: msecs_to_jiffies(m: len + 1000))) { |
114 | dmaengine_terminate_sync(chan: rx_chan); |
115 | dev_err(priv->ctlr->dev, "DMA wait_for_completion_timeout\n" ); |
116 | ret = -ETIMEDOUT; |
117 | } |
118 | |
119 | unmap_dma: |
120 | dma_unmap_single(rx_chan->device->dev, dma_dst, len, DMA_FROM_DEVICE); |
121 | return ret; |
122 | } |
123 | |
124 | static void am654_hbmc_read(struct hyperbus_device *hbdev, void *to, |
125 | unsigned long from, ssize_t len) |
126 | { |
127 | struct am654_hbmc_device_priv *priv = hbdev->priv; |
128 | |
129 | if (len < SZ_1K || am654_hbmc_dma_read(priv, to, from, len)) |
130 | memcpy_fromio(to, hbdev->map.virt + from, len); |
131 | } |
132 | |
133 | static const struct hyperbus_ops am654_hbmc_ops = { |
134 | .calibrate = am654_hbmc_calibrate, |
135 | .copy_from = am654_hbmc_read, |
136 | }; |
137 | |
138 | static int am654_hbmc_request_mmap_dma(struct am654_hbmc_device_priv *priv) |
139 | { |
140 | struct dma_chan *rx_chan; |
141 | dma_cap_mask_t mask; |
142 | |
143 | dma_cap_zero(mask); |
144 | dma_cap_set(DMA_MEMCPY, mask); |
145 | |
146 | rx_chan = dma_request_chan_by_mask(mask: &mask); |
147 | if (IS_ERR(ptr: rx_chan)) { |
148 | if (PTR_ERR(ptr: rx_chan) == -EPROBE_DEFER) |
149 | return -EPROBE_DEFER; |
150 | dev_dbg(priv->ctlr->dev, "No DMA channel available\n" ); |
151 | return 0; |
152 | } |
153 | priv->rx_chan = rx_chan; |
154 | init_completion(x: &priv->rx_dma_complete); |
155 | |
156 | return 0; |
157 | } |
158 | |
159 | static int am654_hbmc_probe(struct platform_device *pdev) |
160 | { |
161 | struct device_node *np = pdev->dev.of_node; |
162 | struct am654_hbmc_device_priv *dev_priv; |
163 | struct device *dev = &pdev->dev; |
164 | struct am654_hbmc_priv *priv; |
165 | struct resource res; |
166 | int ret; |
167 | |
168 | priv = devm_kzalloc(dev, size: sizeof(*priv), GFP_KERNEL); |
169 | if (!priv) |
170 | return -ENOMEM; |
171 | |
172 | platform_set_drvdata(pdev, data: priv); |
173 | |
174 | priv->hbdev.np = of_get_next_child(node: np, NULL); |
175 | ret = of_address_to_resource(dev: priv->hbdev.np, index: 0, r: &res); |
176 | if (ret) |
177 | return ret; |
178 | |
179 | if (of_property_read_bool(np: dev->of_node, propname: "mux-controls" )) { |
180 | struct mux_control *control = devm_mux_control_get(dev, NULL); |
181 | |
182 | if (IS_ERR(ptr: control)) |
183 | return PTR_ERR(ptr: control); |
184 | |
185 | ret = mux_control_select(mux: control, state: 1); |
186 | if (ret) { |
187 | dev_err(dev, "Failed to select HBMC mux\n" ); |
188 | return ret; |
189 | } |
190 | priv->mux_ctrl = control; |
191 | } |
192 | |
193 | priv->hbdev.map.size = resource_size(res: &res); |
194 | priv->hbdev.map.virt = devm_ioremap_resource(dev, res: &res); |
195 | if (IS_ERR(ptr: priv->hbdev.map.virt)) |
196 | return PTR_ERR(ptr: priv->hbdev.map.virt); |
197 | |
198 | priv->ctlr.dev = dev; |
199 | priv->ctlr.ops = &am654_hbmc_ops; |
200 | priv->hbdev.ctlr = &priv->ctlr; |
201 | |
202 | dev_priv = devm_kzalloc(dev, size: sizeof(*dev_priv), GFP_KERNEL); |
203 | if (!dev_priv) { |
204 | ret = -ENOMEM; |
205 | goto disable_mux; |
206 | } |
207 | |
208 | priv->hbdev.priv = dev_priv; |
209 | dev_priv->device_base = res.start; |
210 | dev_priv->ctlr = &priv->ctlr; |
211 | |
212 | ret = am654_hbmc_request_mmap_dma(priv: dev_priv); |
213 | if (ret) |
214 | goto disable_mux; |
215 | |
216 | ret = hyperbus_register_device(hbdev: &priv->hbdev); |
217 | if (ret) { |
218 | dev_err(dev, "failed to register controller\n" ); |
219 | goto release_dma; |
220 | } |
221 | |
222 | return 0; |
223 | release_dma: |
224 | if (dev_priv->rx_chan) |
225 | dma_release_channel(chan: dev_priv->rx_chan); |
226 | disable_mux: |
227 | if (priv->mux_ctrl) |
228 | mux_control_deselect(mux: priv->mux_ctrl); |
229 | return ret; |
230 | } |
231 | |
232 | static void am654_hbmc_remove(struct platform_device *pdev) |
233 | { |
234 | struct am654_hbmc_priv *priv = platform_get_drvdata(pdev); |
235 | struct am654_hbmc_device_priv *dev_priv = priv->hbdev.priv; |
236 | |
237 | hyperbus_unregister_device(hbdev: &priv->hbdev); |
238 | |
239 | if (priv->mux_ctrl) |
240 | mux_control_deselect(mux: priv->mux_ctrl); |
241 | |
242 | if (dev_priv->rx_chan) |
243 | dma_release_channel(chan: dev_priv->rx_chan); |
244 | } |
245 | |
246 | static const struct of_device_id am654_hbmc_dt_ids[] = { |
247 | { |
248 | .compatible = "ti,am654-hbmc" , |
249 | }, |
250 | { /* end of table */ } |
251 | }; |
252 | |
253 | MODULE_DEVICE_TABLE(of, am654_hbmc_dt_ids); |
254 | |
255 | static struct platform_driver am654_hbmc_platform_driver = { |
256 | .probe = am654_hbmc_probe, |
257 | .remove_new = am654_hbmc_remove, |
258 | .driver = { |
259 | .name = "hbmc-am654" , |
260 | .of_match_table = am654_hbmc_dt_ids, |
261 | }, |
262 | }; |
263 | |
264 | module_platform_driver(am654_hbmc_platform_driver); |
265 | |
266 | MODULE_DESCRIPTION("HBMC driver for AM654 SoC" ); |
267 | MODULE_LICENSE("GPL v2" ); |
268 | MODULE_ALIAS("platform:hbmc-am654" ); |
269 | MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>" ); |
270 | |