xref: /linux/drivers/gpu/drm/tiny/arcpgu.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
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_module.h>
19 #include <drm/drm_of.h>
20 #include <drm/drm_probe_helper.h>
21 #include <drm/drm_simple_kms_helper.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/module.h>
24 #include <linux/of_reserved_mem.h>
25 #include <linux/platform_device.h>
26 
27 #define ARCPGU_REG_CTRL		0x00
28 #define ARCPGU_REG_STAT		0x04
29 #define ARCPGU_REG_FMT		0x10
30 #define ARCPGU_REG_HSYNC	0x14
31 #define ARCPGU_REG_VSYNC	0x18
32 #define ARCPGU_REG_ACTIVE	0x1c
33 #define ARCPGU_REG_BUF0_ADDR	0x40
34 #define ARCPGU_REG_STRIDE	0x50
35 #define ARCPGU_REG_START_SET	0x84
36 
37 #define ARCPGU_REG_ID		0x3FC
38 
39 #define ARCPGU_CTRL_ENABLE_MASK	0x02
40 #define ARCPGU_CTRL_VS_POL_MASK	0x1
41 #define ARCPGU_CTRL_VS_POL_OFST	0x3
42 #define ARCPGU_CTRL_HS_POL_MASK	0x1
43 #define ARCPGU_CTRL_HS_POL_OFST	0x4
44 #define ARCPGU_MODE_XRGB8888	BIT(2)
45 #define ARCPGU_STAT_BUSY_MASK	0x02
46 
47 struct arcpgu_drm_private {
48 	struct drm_device	drm;
49 	void __iomem		*regs;
50 	struct clk		*clk;
51 	struct drm_simple_display_pipe pipe;
52 	struct drm_connector	sim_conn;
53 };
54 
55 #define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)
56 
57 #define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)
58 
59 static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
60 				 unsigned int reg, u32 value)
61 {
62 	iowrite32(value, arcpgu->regs + reg);
63 }
64 
65 static inline u32 arc_pgu_read(struct arcpgu_drm_private *arcpgu,
66 			       unsigned int reg)
67 {
68 	return ioread32(arcpgu->regs + reg);
69 }
70 
71 #define XRES_DEF	640
72 #define YRES_DEF	480
73 
74 #define XRES_MAX	8192
75 #define YRES_MAX	8192
76 
77 static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
78 {
79 	int count;
80 
81 	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
82 	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
83 	return count;
84 }
85 
86 static const struct drm_connector_helper_funcs
87 arcpgu_drm_connector_helper_funcs = {
88 	.get_modes = arcpgu_drm_connector_get_modes,
89 };
90 
91 static const struct drm_connector_funcs arcpgu_drm_connector_funcs = {
92 	.reset = drm_atomic_helper_connector_reset,
93 	.fill_modes = drm_helper_probe_single_connector_modes,
94 	.destroy = drm_connector_cleanup,
95 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
96 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
97 };
98 
99 static int arcpgu_drm_sim_init(struct drm_device *drm, struct drm_connector *connector)
100 {
101 	drm_connector_helper_add(connector, &arcpgu_drm_connector_helper_funcs);
102 	return drm_connector_init(drm, connector, &arcpgu_drm_connector_funcs,
103 				  DRM_MODE_CONNECTOR_VIRTUAL);
104 }
105 
106 #define ENCODE_PGU_XY(x, y)	((((x) - 1) << 16) | ((y) - 1))
107 
108 static const u32 arc_pgu_supported_formats[] = {
109 	DRM_FORMAT_RGB565,
110 	DRM_FORMAT_XRGB8888,
111 	DRM_FORMAT_ARGB8888,
112 };
113 
114 static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
115 {
116 	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
117 	uint32_t pixel_format = fb->format->format;
118 	u32 format = DRM_FORMAT_INVALID;
119 	int i;
120 	u32 reg_ctrl;
121 
122 	for (i = 0; i < ARRAY_SIZE(arc_pgu_supported_formats); i++) {
123 		if (arc_pgu_supported_formats[i] == pixel_format)
124 			format = arc_pgu_supported_formats[i];
125 	}
126 
127 	if (WARN_ON(format == DRM_FORMAT_INVALID))
128 		return;
129 
130 	reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
131 	if (format == DRM_FORMAT_RGB565)
132 		reg_ctrl &= ~ARCPGU_MODE_XRGB8888;
133 	else
134 		reg_ctrl |= ARCPGU_MODE_XRGB8888;
135 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
136 }
137 
138 static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *pipe,
139 					       const struct drm_display_mode *mode)
140 {
141 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
142 	long rate, clk_rate = mode->clock * 1000;
143 	long diff = clk_rate / 200; /* +-0.5% allowed by HDMI spec */
144 
145 	rate = clk_round_rate(arcpgu->clk, clk_rate);
146 	if ((max(rate, clk_rate) - min(rate, clk_rate) < diff) && (rate > 0))
147 		return MODE_OK;
148 
149 	return MODE_NOCLOCK;
150 }
151 
152 static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
153 {
154 	struct drm_display_mode *m = &arcpgu->pipe.crtc.state->adjusted_mode;
155 	u32 val;
156 
157 	arc_pgu_write(arcpgu, ARCPGU_REG_FMT,
158 		      ENCODE_PGU_XY(m->crtc_htotal, m->crtc_vtotal));
159 
160 	arc_pgu_write(arcpgu, ARCPGU_REG_HSYNC,
161 		      ENCODE_PGU_XY(m->crtc_hsync_start - m->crtc_hdisplay,
162 				    m->crtc_hsync_end - m->crtc_hdisplay));
163 
164 	arc_pgu_write(arcpgu, ARCPGU_REG_VSYNC,
165 		      ENCODE_PGU_XY(m->crtc_vsync_start - m->crtc_vdisplay,
166 				    m->crtc_vsync_end - m->crtc_vdisplay));
167 
168 	arc_pgu_write(arcpgu, ARCPGU_REG_ACTIVE,
169 		      ENCODE_PGU_XY(m->crtc_hblank_end - m->crtc_hblank_start,
170 				    m->crtc_vblank_end - m->crtc_vblank_start));
171 
172 	val = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
173 
174 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
175 		val |= ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST;
176 	else
177 		val &= ~(ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST);
178 
179 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
180 		val |= ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST;
181 	else
182 		val &= ~(ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST);
183 
184 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, val);
185 	arc_pgu_write(arcpgu, ARCPGU_REG_STRIDE, 0);
186 	arc_pgu_write(arcpgu, ARCPGU_REG_START_SET, 1);
187 
188 	arc_pgu_set_pxl_fmt(arcpgu);
189 
190 	clk_set_rate(arcpgu->clk, m->crtc_clock * 1000);
191 }
192 
193 static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
194 			   struct drm_crtc_state *crtc_state,
195 			   struct drm_plane_state *plane_state)
196 {
197 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
198 
199 	arc_pgu_mode_set(arcpgu);
200 
201 	clk_prepare_enable(arcpgu->clk);
202 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
203 		      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) |
204 		      ARCPGU_CTRL_ENABLE_MASK);
205 }
206 
207 static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
208 {
209 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
210 
211 	clk_disable_unprepare(arcpgu->clk);
212 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
213 			      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) &
214 			      ~ARCPGU_CTRL_ENABLE_MASK);
215 }
216 
217 static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
218 			   struct drm_plane_state *state)
219 {
220 	struct arcpgu_drm_private *arcpgu;
221 	struct drm_gem_cma_object *gem;
222 
223 	if (!pipe->plane.state->fb)
224 		return;
225 
226 	arcpgu = pipe_to_arcpgu_priv(pipe);
227 	gem = drm_fb_cma_get_gem_obj(pipe->plane.state->fb, 0);
228 	arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->paddr);
229 }
230 
231 static const struct drm_simple_display_pipe_funcs arc_pgu_pipe_funcs = {
232 	.update = arc_pgu_update,
233 	.mode_valid = arc_pgu_mode_valid,
234 	.enable	= arc_pgu_enable,
235 	.disable = arc_pgu_disable,
236 };
237 
238 static const struct drm_mode_config_funcs arcpgu_drm_modecfg_funcs = {
239 	.fb_create  = drm_gem_fb_create,
240 	.atomic_check = drm_atomic_helper_check,
241 	.atomic_commit = drm_atomic_helper_commit,
242 };
243 
244 DEFINE_DRM_GEM_CMA_FOPS(arcpgu_drm_ops);
245 
246 static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
247 {
248 	struct platform_device *pdev = to_platform_device(arcpgu->drm.dev);
249 	struct device_node *encoder_node = NULL, *endpoint_node = NULL;
250 	struct drm_connector *connector = NULL;
251 	struct drm_device *drm = &arcpgu->drm;
252 	struct resource *res;
253 	int ret;
254 
255 	arcpgu->clk = devm_clk_get(drm->dev, "pxlclk");
256 	if (IS_ERR(arcpgu->clk))
257 		return PTR_ERR(arcpgu->clk);
258 
259 	ret = drmm_mode_config_init(drm);
260 	if (ret)
261 		return ret;
262 
263 	drm->mode_config.min_width = 0;
264 	drm->mode_config.min_height = 0;
265 	drm->mode_config.max_width = 1920;
266 	drm->mode_config.max_height = 1080;
267 	drm->mode_config.funcs = &arcpgu_drm_modecfg_funcs;
268 
269 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
270 	arcpgu->regs = devm_ioremap_resource(&pdev->dev, res);
271 	if (IS_ERR(arcpgu->regs))
272 		return PTR_ERR(arcpgu->regs);
273 
274 	dev_info(drm->dev, "arc_pgu ID: 0x%x\n",
275 		 arc_pgu_read(arcpgu, ARCPGU_REG_ID));
276 
277 	/* Get the optional framebuffer memory resource */
278 	ret = of_reserved_mem_device_init(drm->dev);
279 	if (ret && ret != -ENODEV)
280 		return ret;
281 
282 	if (dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32)))
283 		return -ENODEV;
284 
285 	/*
286 	 * There is only one output port inside each device. It is linked with
287 	 * encoder endpoint.
288 	 */
289 	endpoint_node = of_graph_get_next_endpoint(pdev->dev.of_node, NULL);
290 	if (endpoint_node) {
291 		encoder_node = of_graph_get_remote_port_parent(endpoint_node);
292 		of_node_put(endpoint_node);
293 	} else {
294 		connector = &arcpgu->sim_conn;
295 		dev_info(drm->dev, "no encoder found. Assumed virtual LCD on simulation platform\n");
296 		ret = arcpgu_drm_sim_init(drm, connector);
297 		if (ret < 0)
298 			return ret;
299 	}
300 
301 	ret = drm_simple_display_pipe_init(drm, &arcpgu->pipe, &arc_pgu_pipe_funcs,
302 					   arc_pgu_supported_formats,
303 					   ARRAY_SIZE(arc_pgu_supported_formats),
304 					   NULL, connector);
305 	if (ret)
306 		return ret;
307 
308 	if (encoder_node) {
309 		struct drm_bridge *bridge;
310 
311 		/* Locate drm bridge from the hdmi encoder DT node */
312 		bridge = of_drm_find_bridge(encoder_node);
313 		if (!bridge)
314 			return -EPROBE_DEFER;
315 
316 		ret = drm_simple_display_pipe_attach_bridge(&arcpgu->pipe, bridge);
317 		if (ret)
318 			return ret;
319 	}
320 
321 	drm_mode_config_reset(drm);
322 	drm_kms_helper_poll_init(drm);
323 
324 	platform_set_drvdata(pdev, drm);
325 	return 0;
326 }
327 
328 static int arcpgu_unload(struct drm_device *drm)
329 {
330 	drm_kms_helper_poll_fini(drm);
331 	drm_atomic_helper_shutdown(drm);
332 
333 	return 0;
334 }
335 
336 #ifdef CONFIG_DEBUG_FS
337 static int arcpgu_show_pxlclock(struct seq_file *m, void *arg)
338 {
339 	struct drm_info_node *node = (struct drm_info_node *)m->private;
340 	struct drm_device *drm = node->minor->dev;
341 	struct arcpgu_drm_private *arcpgu = dev_to_arcpgu(drm);
342 	unsigned long clkrate = clk_get_rate(arcpgu->clk);
343 	unsigned long mode_clock = arcpgu->pipe.crtc.mode.crtc_clock * 1000;
344 
345 	seq_printf(m, "hw  : %lu\n", clkrate);
346 	seq_printf(m, "mode: %lu\n", mode_clock);
347 	return 0;
348 }
349 
350 static struct drm_info_list arcpgu_debugfs_list[] = {
351 	{ "clocks", arcpgu_show_pxlclock, 0 },
352 };
353 
354 static void arcpgu_debugfs_init(struct drm_minor *minor)
355 {
356 	drm_debugfs_create_files(arcpgu_debugfs_list,
357 				 ARRAY_SIZE(arcpgu_debugfs_list),
358 				 minor->debugfs_root, minor);
359 }
360 #endif
361 
362 static const struct drm_driver arcpgu_drm_driver = {
363 	.driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
364 	.name = "arcpgu",
365 	.desc = "ARC PGU Controller",
366 	.date = "20160219",
367 	.major = 1,
368 	.minor = 0,
369 	.patchlevel = 0,
370 	.fops = &arcpgu_drm_ops,
371 	DRM_GEM_CMA_DRIVER_OPS,
372 #ifdef CONFIG_DEBUG_FS
373 	.debugfs_init = arcpgu_debugfs_init,
374 #endif
375 };
376 
377 static int arcpgu_probe(struct platform_device *pdev)
378 {
379 	struct arcpgu_drm_private *arcpgu;
380 	int ret;
381 
382 	arcpgu = devm_drm_dev_alloc(&pdev->dev, &arcpgu_drm_driver,
383 				    struct arcpgu_drm_private, drm);
384 	if (IS_ERR(arcpgu))
385 		return PTR_ERR(arcpgu);
386 
387 	ret = arcpgu_load(arcpgu);
388 	if (ret)
389 		return ret;
390 
391 	ret = drm_dev_register(&arcpgu->drm, 0);
392 	if (ret)
393 		goto err_unload;
394 
395 	drm_fbdev_generic_setup(&arcpgu->drm, 16);
396 
397 	return 0;
398 
399 err_unload:
400 	arcpgu_unload(&arcpgu->drm);
401 
402 	return ret;
403 }
404 
405 static int arcpgu_remove(struct platform_device *pdev)
406 {
407 	struct drm_device *drm = platform_get_drvdata(pdev);
408 
409 	drm_dev_unregister(drm);
410 	arcpgu_unload(drm);
411 
412 	return 0;
413 }
414 
415 static const struct of_device_id arcpgu_of_table[] = {
416 	{.compatible = "snps,arcpgu"},
417 	{}
418 };
419 
420 MODULE_DEVICE_TABLE(of, arcpgu_of_table);
421 
422 static struct platform_driver arcpgu_platform_driver = {
423 	.probe = arcpgu_probe,
424 	.remove = arcpgu_remove,
425 	.driver = {
426 		   .name = "arcpgu",
427 		   .of_match_table = arcpgu_of_table,
428 		   },
429 };
430 
431 drm_module_platform_driver(arcpgu_platform_driver);
432 
433 MODULE_AUTHOR("Carlos Palminha <palminha@synopsys.com>");
434 MODULE_DESCRIPTION("ARC PGU DRM driver");
435 MODULE_LICENSE("GPL");
436