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 
10 #include <drm/clients/drm_client_setup.h>
11 #include <drm/drm_atomic_helper.h>
12 #include <drm/drm_debugfs.h>
13 #include <drm/drm_device.h>
14 #include <drm/drm_drv.h>
15 #include <drm/drm_edid.h>
16 #include <drm/drm_fb_dma_helper.h>
17 #include <drm/drm_fbdev_dma.h>
18 #include <drm/drm_fourcc.h>
19 #include <drm/drm_framebuffer.h>
20 #include <drm/drm_gem_dma_helper.h>
21 #include <drm/drm_gem_framebuffer_helper.h>
22 #include <drm/drm_module.h>
23 #include <drm/drm_of.h>
24 #include <drm/drm_probe_helper.h>
25 #include <drm/drm_simple_kms_helper.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/module.h>
28 #include <linux/of_reserved_mem.h>
29 #include <linux/platform_device.h>
30 
31 #define ARCPGU_REG_CTRL		0x00
32 #define ARCPGU_REG_STAT		0x04
33 #define ARCPGU_REG_FMT		0x10
34 #define ARCPGU_REG_HSYNC	0x14
35 #define ARCPGU_REG_VSYNC	0x18
36 #define ARCPGU_REG_ACTIVE	0x1c
37 #define ARCPGU_REG_BUF0_ADDR	0x40
38 #define ARCPGU_REG_STRIDE	0x50
39 #define ARCPGU_REG_START_SET	0x84
40 
41 #define ARCPGU_REG_ID		0x3FC
42 
43 #define ARCPGU_CTRL_ENABLE_MASK	0x02
44 #define ARCPGU_CTRL_VS_POL_MASK	0x1
45 #define ARCPGU_CTRL_VS_POL_OFST	0x3
46 #define ARCPGU_CTRL_HS_POL_MASK	0x1
47 #define ARCPGU_CTRL_HS_POL_OFST	0x4
48 #define ARCPGU_MODE_XRGB8888	BIT(2)
49 #define ARCPGU_STAT_BUSY_MASK	0x02
50 
51 struct arcpgu_drm_private {
52 	struct drm_device	drm;
53 	void __iomem		*regs;
54 	struct clk		*clk;
55 	struct drm_simple_display_pipe pipe;
56 	struct drm_connector	sim_conn;
57 };
58 
59 #define dev_to_arcpgu(x) container_of(x, struct arcpgu_drm_private, drm)
60 
61 #define pipe_to_arcpgu_priv(x) container_of(x, struct arcpgu_drm_private, pipe)
62 
arc_pgu_write(struct arcpgu_drm_private * arcpgu,unsigned int reg,u32 value)63 static inline void arc_pgu_write(struct arcpgu_drm_private *arcpgu,
64 				 unsigned int reg, u32 value)
65 {
66 	iowrite32(value, arcpgu->regs + reg);
67 }
68 
arc_pgu_read(struct arcpgu_drm_private * arcpgu,unsigned int reg)69 static inline u32 arc_pgu_read(struct arcpgu_drm_private *arcpgu,
70 			       unsigned int reg)
71 {
72 	return ioread32(arcpgu->regs + reg);
73 }
74 
75 #define XRES_DEF	640
76 #define YRES_DEF	480
77 
78 #define XRES_MAX	8192
79 #define YRES_MAX	8192
80 
arcpgu_drm_connector_get_modes(struct drm_connector * connector)81 static int arcpgu_drm_connector_get_modes(struct drm_connector *connector)
82 {
83 	int count;
84 
85 	count = drm_add_modes_noedid(connector, XRES_MAX, YRES_MAX);
86 	drm_set_preferred_mode(connector, XRES_DEF, YRES_DEF);
87 	return count;
88 }
89 
90 static const struct drm_connector_helper_funcs
91 arcpgu_drm_connector_helper_funcs = {
92 	.get_modes = arcpgu_drm_connector_get_modes,
93 };
94 
95 static const struct drm_connector_funcs arcpgu_drm_connector_funcs = {
96 	.reset = drm_atomic_helper_connector_reset,
97 	.fill_modes = drm_helper_probe_single_connector_modes,
98 	.destroy = drm_connector_cleanup,
99 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
100 	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
101 };
102 
arcpgu_drm_sim_init(struct drm_device * drm,struct drm_connector * connector)103 static int arcpgu_drm_sim_init(struct drm_device *drm, struct drm_connector *connector)
104 {
105 	drm_connector_helper_add(connector, &arcpgu_drm_connector_helper_funcs);
106 	return drm_connector_init(drm, connector, &arcpgu_drm_connector_funcs,
107 				  DRM_MODE_CONNECTOR_VIRTUAL);
108 }
109 
110 #define ENCODE_PGU_XY(x, y)	((((x) - 1) << 16) | ((y) - 1))
111 
112 static const u32 arc_pgu_supported_formats[] = {
113 	DRM_FORMAT_RGB565,
114 	DRM_FORMAT_XRGB8888,
115 	DRM_FORMAT_ARGB8888,
116 };
117 
arc_pgu_set_pxl_fmt(struct arcpgu_drm_private * arcpgu)118 static void arc_pgu_set_pxl_fmt(struct arcpgu_drm_private *arcpgu)
119 {
120 	const struct drm_framebuffer *fb = arcpgu->pipe.plane.state->fb;
121 	uint32_t pixel_format = fb->format->format;
122 	u32 format = DRM_FORMAT_INVALID;
123 	int i;
124 	u32 reg_ctrl;
125 
126 	for (i = 0; i < ARRAY_SIZE(arc_pgu_supported_formats); i++) {
127 		if (arc_pgu_supported_formats[i] == pixel_format)
128 			format = arc_pgu_supported_formats[i];
129 	}
130 
131 	if (WARN_ON(format == DRM_FORMAT_INVALID))
132 		return;
133 
134 	reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
135 	if (format == DRM_FORMAT_RGB565)
136 		reg_ctrl &= ~ARCPGU_MODE_XRGB8888;
137 	else
138 		reg_ctrl |= ARCPGU_MODE_XRGB8888;
139 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
140 }
141 
arc_pgu_mode_valid(struct drm_simple_display_pipe * pipe,const struct drm_display_mode * mode)142 static enum drm_mode_status arc_pgu_mode_valid(struct drm_simple_display_pipe *pipe,
143 					       const struct drm_display_mode *mode)
144 {
145 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
146 	long rate, clk_rate = mode->clock * 1000;
147 	long diff = clk_rate / 200; /* +-0.5% allowed by HDMI spec */
148 
149 	rate = clk_round_rate(arcpgu->clk, clk_rate);
150 	if ((max(rate, clk_rate) - min(rate, clk_rate) < diff) && (rate > 0))
151 		return MODE_OK;
152 
153 	return MODE_NOCLOCK;
154 }
155 
arc_pgu_mode_set(struct arcpgu_drm_private * arcpgu)156 static void arc_pgu_mode_set(struct arcpgu_drm_private *arcpgu)
157 {
158 	struct drm_display_mode *m = &arcpgu->pipe.crtc.state->adjusted_mode;
159 	u32 val;
160 
161 	arc_pgu_write(arcpgu, ARCPGU_REG_FMT,
162 		      ENCODE_PGU_XY(m->crtc_htotal, m->crtc_vtotal));
163 
164 	arc_pgu_write(arcpgu, ARCPGU_REG_HSYNC,
165 		      ENCODE_PGU_XY(m->crtc_hsync_start - m->crtc_hdisplay,
166 				    m->crtc_hsync_end - m->crtc_hdisplay));
167 
168 	arc_pgu_write(arcpgu, ARCPGU_REG_VSYNC,
169 		      ENCODE_PGU_XY(m->crtc_vsync_start - m->crtc_vdisplay,
170 				    m->crtc_vsync_end - m->crtc_vdisplay));
171 
172 	arc_pgu_write(arcpgu, ARCPGU_REG_ACTIVE,
173 		      ENCODE_PGU_XY(m->crtc_hblank_end - m->crtc_hblank_start,
174 				    m->crtc_vblank_end - m->crtc_vblank_start));
175 
176 	val = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
177 
178 	if (m->flags & DRM_MODE_FLAG_PVSYNC)
179 		val |= ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST;
180 	else
181 		val &= ~(ARCPGU_CTRL_VS_POL_MASK << ARCPGU_CTRL_VS_POL_OFST);
182 
183 	if (m->flags & DRM_MODE_FLAG_PHSYNC)
184 		val |= ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST;
185 	else
186 		val &= ~(ARCPGU_CTRL_HS_POL_MASK << ARCPGU_CTRL_HS_POL_OFST);
187 
188 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, val);
189 	arc_pgu_write(arcpgu, ARCPGU_REG_STRIDE, 0);
190 	arc_pgu_write(arcpgu, ARCPGU_REG_START_SET, 1);
191 
192 	arc_pgu_set_pxl_fmt(arcpgu);
193 
194 	clk_set_rate(arcpgu->clk, m->crtc_clock * 1000);
195 }
196 
arc_pgu_enable(struct drm_simple_display_pipe * pipe,struct drm_crtc_state * crtc_state,struct drm_plane_state * plane_state)197 static void arc_pgu_enable(struct drm_simple_display_pipe *pipe,
198 			   struct drm_crtc_state *crtc_state,
199 			   struct drm_plane_state *plane_state)
200 {
201 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
202 
203 	arc_pgu_mode_set(arcpgu);
204 
205 	clk_prepare_enable(arcpgu->clk);
206 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
207 		      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) |
208 		      ARCPGU_CTRL_ENABLE_MASK);
209 }
210 
arc_pgu_disable(struct drm_simple_display_pipe * pipe)211 static void arc_pgu_disable(struct drm_simple_display_pipe *pipe)
212 {
213 	struct arcpgu_drm_private *arcpgu = pipe_to_arcpgu_priv(pipe);
214 
215 	clk_disable_unprepare(arcpgu->clk);
216 	arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
217 			      arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) &
218 			      ~ARCPGU_CTRL_ENABLE_MASK);
219 }
220 
arc_pgu_update(struct drm_simple_display_pipe * pipe,struct drm_plane_state * state)221 static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
222 			   struct drm_plane_state *state)
223 {
224 	struct arcpgu_drm_private *arcpgu;
225 	struct drm_gem_dma_object *gem;
226 
227 	if (!pipe->plane.state->fb)
228 		return;
229 
230 	arcpgu = pipe_to_arcpgu_priv(pipe);
231 	gem = drm_fb_dma_get_gem_obj(pipe->plane.state->fb, 0);
232 	arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->dma_addr);
233 }
234 
235 static const struct drm_simple_display_pipe_funcs arc_pgu_pipe_funcs = {
236 	.update = arc_pgu_update,
237 	.mode_valid = arc_pgu_mode_valid,
238 	.enable	= arc_pgu_enable,
239 	.disable = arc_pgu_disable,
240 };
241 
242 static const struct drm_mode_config_funcs arcpgu_drm_modecfg_funcs = {
243 	.fb_create  = drm_gem_fb_create,
244 	.atomic_check = drm_atomic_helper_check,
245 	.atomic_commit = drm_atomic_helper_commit,
246 };
247 
248 DEFINE_DRM_GEM_DMA_FOPS(arcpgu_drm_ops);
249 
arcpgu_load(struct arcpgu_drm_private * arcpgu)250 static int arcpgu_load(struct arcpgu_drm_private *arcpgu)
251 {
252 	struct platform_device *pdev = to_platform_device(arcpgu->drm.dev);
253 	struct device_node *encoder_node = NULL, *endpoint_node = NULL;
254 	struct drm_connector *connector = NULL;
255 	struct drm_device *drm = &arcpgu->drm;
256 	int ret;
257 
258 	arcpgu->clk = devm_clk_get(drm->dev, "pxlclk");
259 	if (IS_ERR(arcpgu->clk))
260 		return PTR_ERR(arcpgu->clk);
261 
262 	ret = drmm_mode_config_init(drm);
263 	if (ret)
264 		return ret;
265 
266 	drm->mode_config.min_width = 0;
267 	drm->mode_config.min_height = 0;
268 	drm->mode_config.max_width = 1920;
269 	drm->mode_config.max_height = 1080;
270 	drm->mode_config.funcs = &arcpgu_drm_modecfg_funcs;
271 
272 	arcpgu->regs = devm_platform_ioremap_resource(pdev, 0);
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_endpoint_by_regs(pdev->dev.of_node, 0, -1);
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 
arcpgu_unload(struct drm_device * drm)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
arcpgu_show_pxlclock(struct seq_file * m,void * arg)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 
arcpgu_debugfs_init(struct drm_minor * minor)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 	.major = 1,
369 	.minor = 0,
370 	.patchlevel = 0,
371 	.fops = &arcpgu_drm_ops,
372 	DRM_GEM_DMA_DRIVER_OPS,
373 	DRM_FBDEV_DMA_DRIVER_OPS,
374 #ifdef CONFIG_DEBUG_FS
375 	.debugfs_init = arcpgu_debugfs_init,
376 #endif
377 };
378 
arcpgu_probe(struct platform_device * pdev)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_client_setup_with_fourcc(&arcpgu->drm, DRM_FORMAT_RGB565);
398 
399 	return 0;
400 
401 err_unload:
402 	arcpgu_unload(&arcpgu->drm);
403 
404 	return ret;
405 }
406 
arcpgu_remove(struct platform_device * pdev)407 static void 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 
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