1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved.
4 *
5 * Parts of this file were based on sources as follows:
6 *
7 * Copyright (c) 2006-2008 Intel Corporation
8 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
9 * Copyright (C) 2011 Texas Instruments
10 */
11
12/**
13 * DOC: ARM PrimeCell PL110 and PL111 CLCD Driver
14 *
15 * The PL110/PL111 is a simple LCD controller that can support TFT
16 * and STN displays. This driver exposes a standard KMS interface
17 * for them.
18 *
19 * The driver currently doesn't expose the cursor.  The DRM API for
20 * cursors requires support for 64x64 ARGB8888 cursor images, while
21 * the hardware can only support 64x64 monochrome with masking
22 * cursors.  While one could imagine trying to hack something together
23 * to look at the ARGB8888 and program reasonable in monochrome, we
24 * just don't expose the cursor at all instead, and leave cursor
25 * support to the application software cursor layer.
26 *
27 * TODO:
28 *
29 * - Fix race between setting plane base address and getting IRQ for
30 *   vsync firing the pageflip completion.
31 *
32 * - Read back hardware state at boot to skip reprogramming the
33 *   hardware when doing a no-op modeset.
34 *
35 * - Use the CLKSEL bit to support switching between the two external
36 *   clock parents.
37 */
38
39#include <linux/amba/bus.h>
40#include <linux/dma-buf.h>
41#include <linux/module.h>
42#include <linux/of.h>
43#include <linux/of_graph.h>
44#include <linux/of_reserved_mem.h>
45#include <linux/shmem_fs.h>
46#include <linux/slab.h>
47#include <linux/version.h>
48
49#include <drm/drm_atomic_helper.h>
50#include <drm/drm_bridge.h>
51#include <drm/drm_drv.h>
52#include <drm/drm_fb_cma_helper.h>
53#include <drm/drm_fb_helper.h>
54#include <drm/drm_gem_cma_helper.h>
55#include <drm/drm_gem_framebuffer_helper.h>
56#include <drm/drm_of.h>
57#include <drm/drm_panel.h>
58#include <drm/drm_probe_helper.h>
59#include <drm/drm_vblank.h>
60
61#include "pl111_drm.h"
62#include "pl111_versatile.h"
63#include "pl111_nomadik.h"
64
65#define DRIVER_DESC      "DRM module for PL111"
66
67static const struct drm_mode_config_funcs mode_config_funcs = {
68	.fb_create = drm_gem_fb_create,
69	.atomic_check = drm_atomic_helper_check,
70	.atomic_commit = drm_atomic_helper_commit,
71};
72
73static int pl111_modeset_init(struct drm_device *dev)
74{
75	struct drm_mode_config *mode_config;
76	struct pl111_drm_dev_private *priv = dev->dev_private;
77	struct device_node *np = dev->dev->of_node;
78	struct device_node *remote;
79	struct drm_panel *panel = NULL;
80	struct drm_bridge *bridge = NULL;
81	bool defer = false;
82	int ret;
83	int i;
84
85	ret = drmm_mode_config_init(dev);
86	if (ret)
87		return ret;
88
89	mode_config = &dev->mode_config;
90	mode_config->funcs = &mode_config_funcs;
91	mode_config->min_width = 1;
92	mode_config->max_width = 1024;
93	mode_config->min_height = 1;
94	mode_config->max_height = 768;
95
96	i = 0;
97	for_each_endpoint_of_node(np, remote) {
98		struct drm_panel *tmp_panel;
99		struct drm_bridge *tmp_bridge;
100
101		dev_dbg(dev->dev, "checking endpoint %d\n", i);
102
103		ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
104						  0, i,
105						  &tmp_panel,
106						  &tmp_bridge);
107		if (ret) {
108			if (ret == -EPROBE_DEFER) {
109				/*
110				 * Something deferred, but that is often just
111				 * another way of saying -ENODEV, but let's
112				 * cast a vote for later deferral.
113				 */
114				defer = true;
115			} else if (ret != -ENODEV) {
116				/* Continue, maybe something else is working */
117				dev_err(dev->dev,
118					"endpoint %d returns %d\n", i, ret);
119			}
120		}
121
122		if (tmp_panel) {
123			dev_info(dev->dev,
124				 "found panel on endpoint %d\n", i);
125			panel = tmp_panel;
126		}
127		if (tmp_bridge) {
128			dev_info(dev->dev,
129				 "found bridge on endpoint %d\n", i);
130			bridge = tmp_bridge;
131		}
132
133		i++;
134	}
135
136	/*
137	 * If we can't find neither panel nor bridge on any of the
138	 * endpoints, and any of them retured -EPROBE_DEFER, then
139	 * let's defer this driver too.
140	 */
141	if ((!panel && !bridge) && defer)
142		return -EPROBE_DEFER;
143
144	if (panel) {
145		bridge = drm_panel_bridge_add_typed(panel,
146						    DRM_MODE_CONNECTOR_Unknown);
147		if (IS_ERR(bridge)) {
148			ret = PTR_ERR(bridge);
149			goto finish;
150		}
151	} else if (bridge) {
152		dev_info(dev->dev, "Using non-panel bridge\n");
153	} else {
154		dev_err(dev->dev, "No bridge, exiting\n");
155		return -ENODEV;
156	}
157
158	priv->bridge = bridge;
159	if (panel) {
160		priv->panel = panel;
161		priv->connector = drm_panel_bridge_connector(bridge);
162	}
163
164	ret = pl111_display_init(dev);
165	if (ret != 0) {
166		dev_err(dev->dev, "Failed to init display\n");
167		goto out_bridge;
168	}
169
170	ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
171						    bridge);
172	if (ret)
173		return ret;
174
175	if (!priv->variant->broken_vblank) {
176		ret = drm_vblank_init(dev, 1);
177		if (ret != 0) {
178			dev_err(dev->dev, "Failed to init vblank\n");
179			goto out_bridge;
180		}
181	}
182
183	drm_mode_config_reset(dev);
184
185	drm_kms_helper_poll_init(dev);
186
187	goto finish;
188
189out_bridge:
190	if (panel)
191		drm_panel_bridge_remove(bridge);
192finish:
193	return ret;
194}
195
196static struct drm_gem_object *
197pl111_gem_import_sg_table(struct drm_device *dev,
198			  struct dma_buf_attachment *attach,
199			  struct sg_table *sgt)
200{
201	struct pl111_drm_dev_private *priv = dev->dev_private;
202
203	/*
204	 * When using device-specific reserved memory we can't import
205	 * DMA buffers: those are passed by reference in any global
206	 * memory and we can only handle a specific range of memory.
207	 */
208	if (priv->use_device_memory)
209		return ERR_PTR(-EINVAL);
210
211	return drm_gem_cma_prime_import_sg_table(dev, attach, sgt);
212}
213
214DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
215
216static struct drm_driver pl111_drm_driver = {
217	.driver_features =
218		DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
219	.ioctls = NULL,
220	.fops = &drm_fops,
221	.name = "pl111",
222	.desc = DRIVER_DESC,
223	.date = "20170317",
224	.major = 1,
225	.minor = 0,
226	.patchlevel = 0,
227	.dumb_create = drm_gem_cma_dumb_create,
228	.gem_free_object_unlocked = drm_gem_cma_free_object,
229	.gem_vm_ops = &drm_gem_cma_vm_ops,
230	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
231	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
232	.gem_prime_import_sg_table = pl111_gem_import_sg_table,
233	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
234	.gem_prime_mmap = drm_gem_cma_prime_mmap,
235	.gem_prime_vmap = drm_gem_cma_prime_vmap,
236
237#if defined(CONFIG_DEBUG_FS)
238	.debugfs_init = pl111_debugfs_init,
239#endif
240};
241
242static int pl111_amba_probe(struct amba_device *amba_dev,
243			    const struct amba_id *id)
244{
245	struct device *dev = &amba_dev->dev;
246	struct pl111_drm_dev_private *priv;
247	const struct pl111_variant_data *variant = id->data;
248	struct drm_device *drm;
249	int ret;
250
251	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
252	if (!priv)
253		return -ENOMEM;
254
255	drm = drm_dev_alloc(&pl111_drm_driver, dev);
256	if (IS_ERR(drm))
257		return PTR_ERR(drm);
258	amba_set_drvdata(amba_dev, drm);
259	priv->drm = drm;
260	drm->dev_private = priv;
261	priv->variant = variant;
262
263	ret = of_reserved_mem_device_init(dev);
264	if (!ret) {
265		dev_info(dev, "using device-specific reserved memory\n");
266		priv->use_device_memory = true;
267	}
268
269	if (of_property_read_u32(dev->of_node, "max-memory-bandwidth",
270				 &priv->memory_bw)) {
271		dev_info(dev, "no max memory bandwidth specified, assume unlimited\n");
272		priv->memory_bw = 0;
273	}
274
275	/* The two main variants swap this register */
276	if (variant->is_pl110 || variant->is_lcdc) {
277		priv->ienb = CLCD_PL110_IENB;
278		priv->ctrl = CLCD_PL110_CNTL;
279	} else {
280		priv->ienb = CLCD_PL111_IENB;
281		priv->ctrl = CLCD_PL111_CNTL;
282	}
283
284	priv->regs = devm_ioremap_resource(dev, &amba_dev->res);
285	if (IS_ERR(priv->regs)) {
286		dev_err(dev, "%s failed mmio\n", __func__);
287		ret = PTR_ERR(priv->regs);
288		goto dev_put;
289	}
290
291	/* This may override some variant settings */
292	ret = pl111_versatile_init(dev, priv);
293	if (ret)
294		goto dev_put;
295
296	pl111_nomadik_init(dev);
297
298	/* turn off interrupts before requesting the irq */
299	writel(0, priv->regs + priv->ienb);
300
301	ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0,
302			       variant->name, priv);
303	if (ret != 0) {
304		dev_err(dev, "%s failed irq %d\n", __func__, ret);
305		return ret;
306	}
307
308	ret = pl111_modeset_init(drm);
309	if (ret != 0)
310		goto dev_put;
311
312	ret = drm_dev_register(drm, 0);
313	if (ret < 0)
314		goto dev_put;
315
316	drm_fbdev_generic_setup(drm, priv->variant->fb_bpp);
317
318	return 0;
319
320dev_put:
321	drm_dev_put(drm);
322	of_reserved_mem_device_release(dev);
323
324	return ret;
325}
326
327static void pl111_amba_remove(struct amba_device *amba_dev)
328{
329	struct device *dev = &amba_dev->dev;
330	struct drm_device *drm = amba_get_drvdata(amba_dev);
331	struct pl111_drm_dev_private *priv = drm->dev_private;
332
333	drm_dev_unregister(drm);
334	if (priv->panel)
335		drm_panel_bridge_remove(priv->bridge);
336	drm_dev_put(drm);
337	of_reserved_mem_device_release(dev);
338}
339
340/*
341 * This early variant lacks the 565 and 444 pixel formats.
342 */
343static const u32 pl110_pixel_formats[] = {
344	DRM_FORMAT_ABGR8888,
345	DRM_FORMAT_XBGR8888,
346	DRM_FORMAT_ARGB8888,
347	DRM_FORMAT_XRGB8888,
348	DRM_FORMAT_ABGR1555,
349	DRM_FORMAT_XBGR1555,
350	DRM_FORMAT_ARGB1555,
351	DRM_FORMAT_XRGB1555,
352};
353
354static const struct pl111_variant_data pl110_variant = {
355	.name = "PL110",
356	.is_pl110 = true,
357	.formats = pl110_pixel_formats,
358	.nformats = ARRAY_SIZE(pl110_pixel_formats),
359	.fb_bpp = 16,
360};
361
362/* RealView, Versatile Express etc use this modern variant */
363static const u32 pl111_pixel_formats[] = {
364	DRM_FORMAT_ABGR8888,
365	DRM_FORMAT_XBGR8888,
366	DRM_FORMAT_ARGB8888,
367	DRM_FORMAT_XRGB8888,
368	DRM_FORMAT_BGR565,
369	DRM_FORMAT_RGB565,
370	DRM_FORMAT_ABGR1555,
371	DRM_FORMAT_XBGR1555,
372	DRM_FORMAT_ARGB1555,
373	DRM_FORMAT_XRGB1555,
374	DRM_FORMAT_ABGR4444,
375	DRM_FORMAT_XBGR4444,
376	DRM_FORMAT_ARGB4444,
377	DRM_FORMAT_XRGB4444,
378};
379
380static const struct pl111_variant_data pl111_variant = {
381	.name = "PL111",
382	.formats = pl111_pixel_formats,
383	.nformats = ARRAY_SIZE(pl111_pixel_formats),
384	.fb_bpp = 32,
385};
386
387static const u32 pl110_nomadik_pixel_formats[] = {
388	DRM_FORMAT_RGB888,
389	DRM_FORMAT_BGR888,
390	DRM_FORMAT_ABGR8888,
391	DRM_FORMAT_XBGR8888,
392	DRM_FORMAT_ARGB8888,
393	DRM_FORMAT_XRGB8888,
394	DRM_FORMAT_BGR565,
395	DRM_FORMAT_RGB565,
396	DRM_FORMAT_ABGR1555,
397	DRM_FORMAT_XBGR1555,
398	DRM_FORMAT_ARGB1555,
399	DRM_FORMAT_XRGB1555,
400	DRM_FORMAT_ABGR4444,
401	DRM_FORMAT_XBGR4444,
402	DRM_FORMAT_ARGB4444,
403	DRM_FORMAT_XRGB4444,
404};
405
406static const struct pl111_variant_data pl110_nomadik_variant = {
407	.name = "LCDC (PL110 Nomadik)",
408	.formats = pl110_nomadik_pixel_formats,
409	.nformats = ARRAY_SIZE(pl110_nomadik_pixel_formats),
410	.is_lcdc = true,
411	.st_bitmux_control = true,
412	.broken_vblank = true,
413	.fb_bpp = 16,
414};
415
416static const struct amba_id pl111_id_table[] = {
417	{
418		.id = 0x00041110,
419		.mask = 0x000fffff,
420		.data = (void *)&pl110_variant,
421	},
422	{
423		.id = 0x00180110,
424		.mask = 0x00fffffe,
425		.data = (void *)&pl110_nomadik_variant,
426	},
427	{
428		.id = 0x00041111,
429		.mask = 0x000fffff,
430		.data = (void *)&pl111_variant,
431	},
432	{0, 0},
433};
434MODULE_DEVICE_TABLE(amba, pl111_id_table);
435
436static struct amba_driver pl111_amba_driver __maybe_unused = {
437	.drv = {
438		.name = "drm-clcd-pl111",
439	},
440	.probe = pl111_amba_probe,
441	.remove = pl111_amba_remove,
442	.id_table = pl111_id_table,
443};
444
445#ifdef CONFIG_ARM_AMBA
446module_amba_driver(pl111_amba_driver);
447#endif
448
449MODULE_DESCRIPTION(DRIVER_DESC);
450MODULE_AUTHOR("ARM Ltd.");
451MODULE_LICENSE("GPL");
452