xref: /linux/drivers/gpu/drm/tiny/arcpgu.c (revision 8137a49e1567726eb10fcf55ad141ac19804ca6b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ARC PGU DRM driver.
4  *
5  * Copyright (C) 2016 Synopsys, Inc. (www.synopsys.com)
6  */
7 
8 #include <linux/clk.h>
9 #include <drm/drm_atomic_helper.h>
10 #include <drm/drm_debugfs.h>
11 #include <drm/drm_device.h>
12 #include <drm/drm_drv.h>
13 #include <drm/drm_fb_cma_helper.h>
14 #include <drm/drm_fb_helper.h>
15 #include <drm/drm_fourcc.h>
16 #include <drm/drm_gem_cma_helper.h>
17 #include <drm/drm_gem_framebuffer_helper.h>
18 #include <drm/drm_of.h>
19 #include <drm/drm_probe_helper.h>
20 #include <drm/drm_simple_kms_helper.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/module.h>
23 #include <linux/of_reserved_mem.h>
24 #include <linux/platform_device.h>
25 
26 #define ARCPGU_REG_CTRL		0x00
27 #define ARCPGU_REG_STAT		0x04
28 #define ARCPGU_REG_FMT		0x10
29 #define ARCPGU_REG_HSYNC	0x14
30 #define ARCPGU_REG_VSYNC	0x18
31 #define ARCPGU_REG_ACTIVE	0x1c
32 #define ARCPGU_REG_BUF0_ADDR	0x40
33 #define ARCPGU_REG_STRIDE	0x50
34 #define ARCPGU_REG_START_SET	0x84
35 
36 #define ARCPGU_REG_ID		0x3FC
37 
38 #define ARCPGU_CTRL_ENABLE_MASK	0x02
39 #define ARCPGU_CTRL_VS_POL_MASK	0x1
40 #define ARCPGU_CTRL_VS_POL_OFST	0x3
41 #define ARCPGU_CTRL_HS_POL_MASK	0x1
42 #define ARCPGU_CTRL_HS_POL_OFST	0x4
43 #define ARCPGU_MODE_XRGB8888	BIT(2)
44 #define ARCPGU_STAT_BUSY_MASK	0x02
45 
46 struct arcpgu_drm_private {
47 	struct drm_device	drm;
48 	void __iomem		*regs;
49 	struct clk		*clk;
50 	struct drm_simple_display_pipe pipe;
51 	struct drm_connector	sim_conn;
52 };
53 
54 #define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)
55 
56 #define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)
57 
58 static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
59 				 unsigned int reg, u32 value)
60 {
61 	iowrite32(value, arcpgu->regs + reg);
62 }
63 
64 static inline u32 arc_pgu_read(struct arcpgu_drm_private *arcpgu,
65 			       unsigned int reg)
66 {
67 	return ioread32(arcpgu->regs + reg);
68 }
69 
70 #define XRES_DEF	640
71 #define YRES_DEF	480
72 
73 #define XRES_MAX	8192
74 #define YRES_MAX	8192
75 
76 static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
77 {
78 	int count;
79 
80 	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
81 	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
82 	return count;
83 }
84 
85 static const struct drm_connector_helper_funcs
86 arcpgu_drm_connector_helper_funcs = {
87 	.get_modes = arcpgu_drm_connector_get_modes,
88 };
89 
90 static const struct drm_connector_funcs arcpgu_drm_connector_funcs = {
91 	.reset = drm_atomic_helper_connector_reset,
92 	.fill_modes = drm_helper_probe_single_connector_modes,
93 	.destroy = drm_connector_cleanup,
94 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
95 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
96 };
97 
98 static int arcpgu_drm_sim_init(struct drm_device *drm, struct drm_connector *connector)
99 {
100 	drm_connector_helper_add(connector, &arcpgu_drm_connector_helper_funcs);
101 	return drm_connector_init(drm, connector, &arcpgu_drm_connector_funcs,
102 				  DRM_MODE_CONNECTOR_VIRTUAL);
103 }
104 
105 #define ENCODE_PGU_XY(x, y)	((((x) - 1) << 16) | ((y) - 1))
106 
107 static const u32 arc_pgu_supported_formats[] = {
108 	DRM_FORMAT_RGB565,
109 	DRM_FORMAT_XRGB8888,
110 	DRM_FORMAT_ARGB8888,
111 };
112 
113 static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
114 {
115 	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
116 	uint32_t pixel_format = fb->format->format;
117 	u32 format = DRM_FORMAT_INVALID;
118 	int i;
119 	u32 reg_ctrl;
120 
121 	for (i = 0; i < ARRAY_SIZE(arc_pgu_supported_formats); i++) {
122 		if (arc_pgu_supported_formats[i] == pixel_format)
123 			format = arc_pgu_supported_formats[i];
124 	}
125 
126 	if (WARN_ON(format == DRM_FORMAT_INVALID))
127 		return;
128 
129 	reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
130 	if (format == DRM_FORMAT_RGB565)
131 		reg_ctrl &= ~ARCPGU_MODE_XRGB8888;
132 	else
133 		reg_ctrl |= ARCPGU_MODE_XRGB8888;
134 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
135 }
136 
137 static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *pipe,
138 					       const struct drm_display_mode *mode)
139 {
140 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
141 	long rate, clk_rate = mode->clock * 1000;
142 	long diff = clk_rate / 200; /* +-0.5% allowed by HDMI spec */
143 
144 	rate = clk_round_rate(arcpgu->clk, clk_rate);
145 	if ((max(rate, clk_rate) - min(rate, clk_rate) < diff) && (rate > 0))
146 		return MODE_OK;
147 
148 	return MODE_NOCLOCK;
149 }
150 
151 static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
152 {
153 	struct drm_display_mode *m = &arcpgu->pipe.crtc.state->adjusted_mode;
154 	u32 val;
155 
156 	arc_pgu_write(arcpgu, ARCPGU_REG_FMT,
157 		      ENCODE_PGU_XY(m->crtc_htotal, m->crtc_vtotal));
158 
159 	arc_pgu_write(arcpgu, ARCPGU_REG_HSYNC,
160 		      ENCODE_PGU_XY(m->crtc_hsync_start - m->crtc_hdisplay,
161 				    m->crtc_hsync_end - m->crtc_hdisplay));
162 
163 	arc_pgu_write(arcpgu, ARCPGU_REG_VSYNC,
164 		      ENCODE_PGU_XY(m->crtc_vsync_start - m->crtc_vdisplay,
165 				    m->crtc_vsync_end - m->crtc_vdisplay));
166 
167 	arc_pgu_write(arcpgu, ARCPGU_REG_ACTIVE,
168 		      ENCODE_PGU_XY(m->crtc_hblank_end - m->crtc_hblank_start,
169 				    m->crtc_vblank_end - m->crtc_vblank_start));
170 
171 	val = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
172 
173 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
174 		val |= ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST;
175 	else
176 		val &= ~(ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST);
177 
178 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
179 		val |= ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST;
180 	else
181 		val &= ~(ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST);
182 
183 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, val);
184 	arc_pgu_write(arcpgu, ARCPGU_REG_STRIDE, 0);
185 	arc_pgu_write(arcpgu, ARCPGU_REG_START_SET, 1);
186 
187 	arc_pgu_set_pxl_fmt(arcpgu);
188 
189 	clk_set_rate(arcpgu->clk, m->crtc_clock * 1000);
190 }
191 
192 static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
193 			   struct drm_crtc_state *crtc_state,
194 			   struct drm_plane_state *plane_state)
195 {
196 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
197 
198 	arc_pgu_mode_set(arcpgu);
199 
200 	clk_prepare_enable(arcpgu->clk);
201 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
202 		      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) |
203 		      ARCPGU_CTRL_ENABLE_MASK);
204 }
205 
206 static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
207 {
208 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
209 
210 	clk_disable_unprepare(arcpgu->clk);
211 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
212 			      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) &
213 			      ~ARCPGU_CTRL_ENABLE_MASK);
214 }
215 
216 static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
217 			   struct drm_plane_state *state)
218 {
219 	struct arcpgu_drm_private *arcpgu;
220 	struct drm_gem_cma_object *gem;
221 
222 	if (!pipe->plane.state->fb)
223 		return;
224 
225 	arcpgu = pipe_to_arcpgu_priv(pipe);
226 	gem = drm_fb_cma_get_gem_obj(pipe->plane.state->fb, 0);
227 	arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->paddr);
228 }
229 
230 static const struct drm_simple_display_pipe_funcs arc_pgu_pipe_funcs = {
231 	.update = arc_pgu_update,
232 	.mode_valid = arc_pgu_mode_valid,
233 	.enable	= arc_pgu_enable,
234 	.disable = arc_pgu_disable,
235 };
236 
237 static const struct drm_mode_config_funcs arcpgu_drm_modecfg_funcs = {
238 	.fb_create  = drm_gem_fb_create,
239 	.atomic_check = drm_atomic_helper_check,
240 	.atomic_commit = drm_atomic_helper_commit,
241 };
242 
243 DEFINE_DRM_GEM_CMA_FOPS(arcpgu_drm_ops);
244 
245 static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
246 {
247 	struct platform_device *pdev = to_platform_device(arcpgu->drm.dev);
248 	struct device_node *encoder_node = NULL, *endpoint_node = NULL;
249 	struct drm_connector *connector = NULL;
250 	struct drm_device *drm = &arcpgu->drm;
251 	struct resource *res;
252 	int ret;
253 
254 	arcpgu->clk = devm_clk_get(drm->dev, "pxlclk");
255 	if (IS_ERR(arcpgu->clk))
256 		return PTR_ERR(arcpgu->clk);
257 
258 	ret = drmm_mode_config_init(drm);
259 	if (ret)
260 		return ret;
261 
262 	drm->mode_config.min_width = 0;
263 	drm->mode_config.min_height = 0;
264 	drm->mode_config.max_width = 1920;
265 	drm->mode_config.max_height = 1080;
266 	drm->mode_config.funcs = &arcpgu_drm_modecfg_funcs;
267 
268 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
269 	arcpgu->regs = devm_ioremap_resource(&pdev->dev, res);
270 	if (IS_ERR(arcpgu->regs))
271 		return PTR_ERR(arcpgu->regs);
272 
273 	dev_info(drm->dev, "arc_pgu ID: 0x%x\n",
274 		 arc_pgu_read(arcpgu, ARCPGU_REG_ID));
275 
276 	/* Get the optional framebuffer memory resource */
277 	ret = of_reserved_mem_device_init(drm->dev);
278 	if (ret && ret != -ENODEV)
279 		return ret;
280 
281 	if (dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32)))
282 		return -ENODEV;
283 
284 	/*
285 	 * There is only one output port inside each device. It is linked with
286 	 * encoder endpoint.
287 	 */
288 	endpoint_node = of_graph_get_next_endpoint(pdev->dev.of_node, NULL);
289 	if (endpoint_node) {
290 		encoder_node = of_graph_get_remote_port_parent(endpoint_node);
291 		of_node_put(endpoint_node);
292 	} else {
293 		connector = &arcpgu->sim_conn;
294 		dev_info(drm->dev, "no encoder found. Assumed virtual LCD on simulation platform\n");
295 		ret = arcpgu_drm_sim_init(drm, connector);
296 		if (ret < 0)
297 			return ret;
298 	}
299 
300 	ret = drm_simple_display_pipe_init(drm, &arcpgu->pipe, &arc_pgu_pipe_funcs,
301 					   arc_pgu_supported_formats,
302 					   ARRAY_SIZE(arc_pgu_supported_formats),
303 					   NULL, connector);
304 	if (ret)
305 		return ret;
306 
307 	if (encoder_node) {
308 		struct drm_bridge *bridge;
309 
310 		/* Locate drm bridge from the hdmi encoder DT node */
311 		bridge = of_drm_find_bridge(encoder_node);
312 		if (!bridge)
313 			return -EPROBE_DEFER;
314 
315 		ret = drm_simple_display_pipe_attach_bridge(&arcpgu->pipe, bridge);
316 		if (ret)
317 			return ret;
318 	}
319 
320 	drm_mode_config_reset(drm);
321 	drm_kms_helper_poll_init(drm);
322 
323 	platform_set_drvdata(pdev, drm);
324 	return 0;
325 }
326 
327 static int arcpgu_unload(struct drm_device *drm)
328 {
329 	drm_kms_helper_poll_fini(drm);
330 	drm_atomic_helper_shutdown(drm);
331 
332 	return 0;
333 }
334 
335 #ifdef CONFIG_DEBUG_FS
336 static int arcpgu_show_pxlclock(struct seq_file *m, void *arg)
337 {
338 	struct drm_info_node *node = (struct drm_info_node *)m->private;
339 	struct drm_device *drm = node->minor->dev;
340 	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(drm);
341 	unsigned long clkrate = clk_get_rate(arcpgu->clk);
342 	unsigned long mode_clock = arcpgu->pipe.crtc.mode.crtc_clock * 1000;
343 
344 	seq_printf(m, "hw  : %lu\n", clkrate);
345 	seq_printf(m, "mode: %lu\n", mode_clock);
346 	return 0;
347 }
348 
349 static struct drm_info_list arcpgu_debugfs_list[] = {
350 	{ "clocks", arcpgu_show_pxlclock, 0 },
351 };
352 
353 static void arcpgu_debugfs_init(struct drm_minor *minor)
354 {
355 	drm_debugfs_create_files(arcpgu_debugfs_list,
356 				 ARRAY_SIZE(arcpgu_debugfs_list),
357 				 minor->debugfs_root, minor);
358 }
359 #endif
360 
361 static const struct drm_driver arcpgu_drm_driver = {
362 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
363 	.name = "arcpgu",
364 	.desc = "ARC PGU Controller",
365 	.date = "20160219",
366 	.major = 1,
367 	.minor = 0,
368 	.patchlevel = 0,
369 	.fops = &arcpgu_drm_ops,
370 	DRM_GEM_CMA_DRIVER_OPS,
371 #ifdef CONFIG_DEBUG_FS
372 	.debugfs_init = arcpgu_debugfs_init,
373 #endif
374 };
375 
376 static int arcpgu_probe(struct platform_device *pdev)
377 {
378 	struct arcpgu_drm_private *arcpgu;
379 	int ret;
380 
381 	arcpgu = devm_drm_dev_alloc(&pdev->dev, &arcpgu_drm_driver,
382 				    struct arcpgu_drm_private, drm);
383 	if (IS_ERR(arcpgu))
384 		return PTR_ERR(arcpgu);
385 
386 	ret = arcpgu_load(arcpgu);
387 	if (ret)
388 		return ret;
389 
390 	ret = drm_dev_register(&arcpgu->drm, 0);
391 	if (ret)
392 		goto err_unload;
393 
394 	drm_fbdev_generic_setup(&arcpgu->drm, 16);
395 
396 	return 0;
397 
398 err_unload:
399 	arcpgu_unload(&arcpgu->drm);
400 
401 	return ret;
402 }
403 
404 static int arcpgu_remove(struct platform_device *pdev)
405 {
406 	struct drm_device *drm = platform_get_drvdata(pdev);
407 
408 	drm_dev_unregister(drm);
409 	arcpgu_unload(drm);
410 
411 	return 0;
412 }
413 
414 static const struct of_device_id arcpgu_of_table[] = {
415 	{.compatible = "snps,arcpgu"},
416 	{}
417 };
418 
419 MODULE_DEVICE_TABLE(of, arcpgu_of_table);
420 
421 static struct platform_driver arcpgu_platform_driver = {
422 	.probe = arcpgu_probe,
423 	.remove = arcpgu_remove,
424 	.driver = {
425 		   .name = "arcpgu",
426 		   .of_match_table = arcpgu_of_table,
427 		   },
428 };
429 
430 module_platform_driver(arcpgu_platform_driver);
431 
432 MODULE_AUTHOR("Carlos Palminha <palminha@synopsys.com>");
433 MODULE_DESCRIPTION("ARC PGU DRM driver");
434 MODULE_LICENSE("GPL");
435