xref: /linux/drivers/gpu/drm/tiny/arcpgu.c (revision fb2ac84f8acccdec644d26dfc8ba6554f30cd6c0)
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_edid.h>
14 #include <drm/drm_fb_cma_helper.h>
15 #include <drm/drm_fb_helper.h>
16 #include <drm/drm_fourcc.h>
17 #include <drm/drm_framebuffer.h>
18 #include <drm/drm_gem_cma_helper.h>
19 #include <drm/drm_gem_framebuffer_helper.h>
20 #include <drm/drm_module.h>
21 #include <drm/drm_of.h>
22 #include <drm/drm_probe_helper.h>
23 #include <drm/drm_simple_kms_helper.h>
24 #include <linux/dma-mapping.h>
25 #include <linux/module.h>
26 #include <linux/of_reserved_mem.h>
27 #include <linux/platform_device.h>
28 
29 #define ARCPGU_REG_CTRL		0x00
30 #define ARCPGU_REG_STAT		0x04
31 #define ARCPGU_REG_FMT		0x10
32 #define ARCPGU_REG_HSYNC	0x14
33 #define ARCPGU_REG_VSYNC	0x18
34 #define ARCPGU_REG_ACTIVE	0x1c
35 #define ARCPGU_REG_BUF0_ADDR	0x40
36 #define ARCPGU_REG_STRIDE	0x50
37 #define ARCPGU_REG_START_SET	0x84
38 
39 #define ARCPGU_REG_ID		0x3FC
40 
41 #define ARCPGU_CTRL_ENABLE_MASK	0x02
42 #define ARCPGU_CTRL_VS_POL_MASK	0x1
43 #define ARCPGU_CTRL_VS_POL_OFST	0x3
44 #define ARCPGU_CTRL_HS_POL_MASK	0x1
45 #define ARCPGU_CTRL_HS_POL_OFST	0x4
46 #define ARCPGU_MODE_XRGB8888	BIT(2)
47 #define ARCPGU_STAT_BUSY_MASK	0x02
48 
49 struct arcpgu_drm_private {
50 	struct drm_device	drm;
51 	void __iomem		*regs;
52 	struct clk		*clk;
53 	struct drm_simple_display_pipe pipe;
54 	struct drm_connector	sim_conn;
55 };
56 
57 #define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)
58 
59 #define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)
60 
61 static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
62 				 unsigned int reg, u32 value)
63 {
64 	iowrite32(value, arcpgu->regs + reg);
65 }
66 
67 static inline u32 arc_pgu_read(struct arcpgu_drm_private *arcpgu,
68 			       unsigned int reg)
69 {
70 	return ioread32(arcpgu->regs + reg);
71 }
72 
73 #define XRES_DEF	640
74 #define YRES_DEF	480
75 
76 #define XRES_MAX	8192
77 #define YRES_MAX	8192
78 
79 static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
80 {
81 	int count;
82 
83 	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
84 	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
85 	return count;
86 }
87 
88 static const struct drm_connector_helper_funcs
89 arcpgu_drm_connector_helper_funcs = {
90 	.get_modes = arcpgu_drm_connector_get_modes,
91 };
92 
93 static const struct drm_connector_funcs arcpgu_drm_connector_funcs = {
94 	.reset = drm_atomic_helper_connector_reset,
95 	.fill_modes = drm_helper_probe_single_connector_modes,
96 	.destroy = drm_connector_cleanup,
97 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
98 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
99 };
100 
101 static int arcpgu_drm_sim_init(struct drm_device *drm, struct drm_connector *connector)
102 {
103 	drm_connector_helper_add(connector, &arcpgu_drm_connector_helper_funcs);
104 	return drm_connector_init(drm, connector, &arcpgu_drm_connector_funcs,
105 				  DRM_MODE_CONNECTOR_VIRTUAL);
106 }
107 
108 #define ENCODE_PGU_XY(x, y)	((((x) - 1) << 16) | ((y) - 1))
109 
110 static const u32 arc_pgu_supported_formats[] = {
111 	DRM_FORMAT_RGB565,
112 	DRM_FORMAT_XRGB8888,
113 	DRM_FORMAT_ARGB8888,
114 };
115 
116 static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
117 {
118 	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
119 	uint32_t pixel_format = fb->format->format;
120 	u32 format = DRM_FORMAT_INVALID;
121 	int i;
122 	u32 reg_ctrl;
123 
124 	for (i = 0; i < ARRAY_SIZE(arc_pgu_supported_formats); i++) {
125 		if (arc_pgu_supported_formats[i] == pixel_format)
126 			format = arc_pgu_supported_formats[i];
127 	}
128 
129 	if (WARN_ON(format == DRM_FORMAT_INVALID))
130 		return;
131 
132 	reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
133 	if (format == DRM_FORMAT_RGB565)
134 		reg_ctrl &= ~ARCPGU_MODE_XRGB8888;
135 	else
136 		reg_ctrl |= ARCPGU_MODE_XRGB8888;
137 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
138 }
139 
140 static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *pipe,
141 					       const struct drm_display_mode *mode)
142 {
143 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
144 	long rate, clk_rate = mode->clock * 1000;
145 	long diff = clk_rate / 200; /* +-0.5% allowed by HDMI spec */
146 
147 	rate = clk_round_rate(arcpgu->clk, clk_rate);
148 	if ((max(rate, clk_rate) - min(rate, clk_rate) < diff) && (rate > 0))
149 		return MODE_OK;
150 
151 	return MODE_NOCLOCK;
152 }
153 
154 static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
155 {
156 	struct drm_display_mode *m = &arcpgu->pipe.crtc.state->adjusted_mode;
157 	u32 val;
158 
159 	arc_pgu_write(arcpgu, ARCPGU_REG_FMT,
160 		      ENCODE_PGU_XY(m->crtc_htotal, m->crtc_vtotal));
161 
162 	arc_pgu_write(arcpgu, ARCPGU_REG_HSYNC,
163 		      ENCODE_PGU_XY(m->crtc_hsync_start - m->crtc_hdisplay,
164 				    m->crtc_hsync_end - m->crtc_hdisplay));
165 
166 	arc_pgu_write(arcpgu, ARCPGU_REG_VSYNC,
167 		      ENCODE_PGU_XY(m->crtc_vsync_start - m->crtc_vdisplay,
168 				    m->crtc_vsync_end - m->crtc_vdisplay));
169 
170 	arc_pgu_write(arcpgu, ARCPGU_REG_ACTIVE,
171 		      ENCODE_PGU_XY(m->crtc_hblank_end - m->crtc_hblank_start,
172 				    m->crtc_vblank_end - m->crtc_vblank_start));
173 
174 	val = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
175 
176 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
177 		val |= ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST;
178 	else
179 		val &= ~(ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST);
180 
181 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
182 		val |= ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST;
183 	else
184 		val &= ~(ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST);
185 
186 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, val);
187 	arc_pgu_write(arcpgu, ARCPGU_REG_STRIDE, 0);
188 	arc_pgu_write(arcpgu, ARCPGU_REG_START_SET, 1);
189 
190 	arc_pgu_set_pxl_fmt(arcpgu);
191 
192 	clk_set_rate(arcpgu->clk, m->crtc_clock * 1000);
193 }
194 
195 static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
196 			   struct drm_crtc_state *crtc_state,
197 			   struct drm_plane_state *plane_state)
198 {
199 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
200 
201 	arc_pgu_mode_set(arcpgu);
202 
203 	clk_prepare_enable(arcpgu->clk);
204 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
205 		      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) |
206 		      ARCPGU_CTRL_ENABLE_MASK);
207 }
208 
209 static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
210 {
211 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
212 
213 	clk_disable_unprepare(arcpgu->clk);
214 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
215 			      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) &
216 			      ~ARCPGU_CTRL_ENABLE_MASK);
217 }
218 
219 static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
220 			   struct drm_plane_state *state)
221 {
222 	struct arcpgu_drm_private *arcpgu;
223 	struct drm_gem_cma_object *gem;
224 
225 	if (!pipe->plane.state->fb)
226 		return;
227 
228 	arcpgu = pipe_to_arcpgu_priv(pipe);
229 	gem = drm_fb_cma_get_gem_obj(pipe->plane.state->fb, 0);
230 	arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->paddr);
231 }
232 
233 static const struct drm_simple_display_pipe_funcs arc_pgu_pipe_funcs = {
234 	.update = arc_pgu_update,
235 	.mode_valid = arc_pgu_mode_valid,
236 	.enable	= arc_pgu_enable,
237 	.disable = arc_pgu_disable,
238 };
239 
240 static const struct drm_mode_config_funcs arcpgu_drm_modecfg_funcs = {
241 	.fb_create  = drm_gem_fb_create,
242 	.atomic_check = drm_atomic_helper_check,
243 	.atomic_commit = drm_atomic_helper_commit,
244 };
245 
246 DEFINE_DRM_GEM_CMA_FOPS(arcpgu_drm_ops);
247 
248 static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
249 {
250 	struct platform_device *pdev = to_platform_device(arcpgu->drm.dev);
251 	struct device_node *encoder_node = NULL, *endpoint_node = NULL;
252 	struct drm_connector *connector = NULL;
253 	struct drm_device *drm = &arcpgu->drm;
254 	struct resource *res;
255 	int ret;
256 
257 	arcpgu->clk = devm_clk_get(drm->dev, "pxlclk");
258 	if (IS_ERR(arcpgu->clk))
259 		return PTR_ERR(arcpgu->clk);
260 
261 	ret = drmm_mode_config_init(drm);
262 	if (ret)
263 		return ret;
264 
265 	drm->mode_config.min_width = 0;
266 	drm->mode_config.min_height = 0;
267 	drm->mode_config.max_width = 1920;
268 	drm->mode_config.max_height = 1080;
269 	drm->mode_config.funcs = &arcpgu_drm_modecfg_funcs;
270 
271 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
272 	arcpgu->regs = devm_ioremap_resource(&pdev->dev, res);
273 	if (IS_ERR(arcpgu->regs))
274 		return PTR_ERR(arcpgu->regs);
275 
276 	dev_info(drm->dev, "arc_pgu ID: 0x%x\n",
277 		 arc_pgu_read(arcpgu, ARCPGU_REG_ID));
278 
279 	/* Get the optional framebuffer memory resource */
280 	ret = of_reserved_mem_device_init(drm->dev);
281 	if (ret && ret != -ENODEV)
282 		return ret;
283 
284 	if (dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32)))
285 		return -ENODEV;
286 
287 	/*
288 	 * There is only one output port inside each device. It is linked with
289 	 * encoder endpoint.
290 	 */
291 	endpoint_node = of_graph_get_next_endpoint(pdev->dev.of_node, NULL);
292 	if (endpoint_node) {
293 		encoder_node = of_graph_get_remote_port_parent(endpoint_node);
294 		of_node_put(endpoint_node);
295 	} else {
296 		connector = &arcpgu->sim_conn;
297 		dev_info(drm->dev, "no encoder found. Assumed virtual LCD on simulation platform\n");
298 		ret = arcpgu_drm_sim_init(drm, connector);
299 		if (ret < 0)
300 			return ret;
301 	}
302 
303 	ret = drm_simple_display_pipe_init(drm, &arcpgu->pipe, &arc_pgu_pipe_funcs,
304 					   arc_pgu_supported_formats,
305 					   ARRAY_SIZE(arc_pgu_supported_formats),
306 					   NULL, connector);
307 	if (ret)
308 		return ret;
309 
310 	if (encoder_node) {
311 		struct drm_bridge *bridge;
312 
313 		/* Locate drm bridge from the hdmi encoder DT node */
314 		bridge = of_drm_find_bridge(encoder_node);
315 		if (!bridge)
316 			return -EPROBE_DEFER;
317 
318 		ret = drm_simple_display_pipe_attach_bridge(&arcpgu->pipe, bridge);
319 		if (ret)
320 			return ret;
321 	}
322 
323 	drm_mode_config_reset(drm);
324 	drm_kms_helper_poll_init(drm);
325 
326 	platform_set_drvdata(pdev, drm);
327 	return 0;
328 }
329 
330 static int arcpgu_unload(struct drm_device *drm)
331 {
332 	drm_kms_helper_poll_fini(drm);
333 	drm_atomic_helper_shutdown(drm);
334 
335 	return 0;
336 }
337 
338 #ifdef CONFIG_DEBUG_FS
339 static int arcpgu_show_pxlclock(struct seq_file *m, void *arg)
340 {
341 	struct drm_info_node *node = (struct drm_info_node *)m->private;
342 	struct drm_device *drm = node->minor->dev;
343 	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(drm);
344 	unsigned long clkrate = clk_get_rate(arcpgu->clk);
345 	unsigned long mode_clock = arcpgu->pipe.crtc.mode.crtc_clock * 1000;
346 
347 	seq_printf(m, "hw  : %lu\n", clkrate);
348 	seq_printf(m, "mode: %lu\n", mode_clock);
349 	return 0;
350 }
351 
352 static struct drm_info_list arcpgu_debugfs_list[] = {
353 	{ "clocks", arcpgu_show_pxlclock, 0 },
354 };
355 
356 static void arcpgu_debugfs_init(struct drm_minor *minor)
357 {
358 	drm_debugfs_create_files(arcpgu_debugfs_list,
359 				 ARRAY_SIZE(arcpgu_debugfs_list),
360 				 minor->debugfs_root, minor);
361 }
362 #endif
363 
364 static const struct drm_driver arcpgu_drm_driver = {
365 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
366 	.name = "arcpgu",
367 	.desc = "ARC PGU Controller",
368 	.date = "20160219",
369 	.major = 1,
370 	.minor = 0,
371 	.patchlevel = 0,
372 	.fops = &arcpgu_drm_ops,
373 	DRM_GEM_CMA_DRIVER_OPS,
374 #ifdef CONFIG_DEBUG_FS
375 	.debugfs_init = arcpgu_debugfs_init,
376 #endif
377 };
378 
379 static int arcpgu_probe(struct platform_device *pdev)
380 {
381 	struct arcpgu_drm_private *arcpgu;
382 	int ret;
383 
384 	arcpgu = devm_drm_dev_alloc(&pdev->dev, &arcpgu_drm_driver,
385 				    struct arcpgu_drm_private, drm);
386 	if (IS_ERR(arcpgu))
387 		return PTR_ERR(arcpgu);
388 
389 	ret = arcpgu_load(arcpgu);
390 	if (ret)
391 		return ret;
392 
393 	ret = drm_dev_register(&arcpgu->drm, 0);
394 	if (ret)
395 		goto err_unload;
396 
397 	drm_fbdev_generic_setup(&arcpgu->drm, 16);
398 
399 	return 0;
400 
401 err_unload:
402 	arcpgu_unload(&arcpgu->drm);
403 
404 	return ret;
405 }
406 
407 static int arcpgu_remove(struct platform_device *pdev)
408 {
409 	struct drm_device *drm = platform_get_drvdata(pdev);
410 
411 	drm_dev_unregister(drm);
412 	arcpgu_unload(drm);
413 
414 	return 0;
415 }
416 
417 static const struct of_device_id arcpgu_of_table[] = {
418 	{.compatible = "snps,arcpgu"},
419 	{}
420 };
421 
422 MODULE_DEVICE_TABLE(of, arcpgu_of_table);
423 
424 static struct platform_driver arcpgu_platform_driver = {
425 	.probe = arcpgu_probe,
426 	.remove = arcpgu_remove,
427 	.driver = {
428 		   .name = "arcpgu",
429 		   .of_match_table = arcpgu_of_table,
430 		   },
431 };
432 
433 drm_module_platform_driver(arcpgu_platform_driver);
434 
435 MODULE_AUTHOR("Carlos Palminha <palminha@synopsys.com>");
436 MODULE_DESCRIPTION("ARC PGU DRM driver");
437 MODULE_LICENSE("GPL");
438