xref: /linux/drivers/video/fbdev/omap2/omapfb/vrfb.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * VRFB Rotation Engine
4  *
5  * Copyright (C) 2009 Nokia Corporation
6  * Author: Tomi Valkeinen <tomi.valkeinen@nokia.com>
7  */
8 
9 /*#define DEBUG*/
10 
11 #include <linux/err.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/ioport.h>
15 #include <linux/io.h>
16 #include <linux/bitops.h>
17 #include <linux/mutex.h>
18 #include <linux/platform_device.h>
19 
20 #include <video/omapvrfb.h>
21 
22 #ifdef DEBUG
23 #define DBG(format, ...) pr_debug("VRFB: " format, ## __VA_ARGS__)
24 #else
25 #define DBG(format, ...)
26 #endif
27 
28 #define SMS_ROT_CONTROL(context)	(0x0 + 0x10 * context)
29 #define SMS_ROT_SIZE(context)		(0x4 + 0x10 * context)
30 #define SMS_ROT_PHYSICAL_BA(context)	(0x8 + 0x10 * context)
31 #define SMS_ROT_VIRT_BASE(rot)		(0x1000000 * (rot))
32 
33 #define OMAP_VRFB_SIZE			(2048 * 2048 * 4)
34 
35 #define VRFB_PAGE_WIDTH_EXP	5 /* Assuming SDRAM pagesize= 1024 */
36 #define VRFB_PAGE_HEIGHT_EXP	5 /* 1024 = 2^5 * 2^5 */
37 #define VRFB_PAGE_WIDTH		(1 << VRFB_PAGE_WIDTH_EXP)
38 #define VRFB_PAGE_HEIGHT	(1 << VRFB_PAGE_HEIGHT_EXP)
39 #define SMS_IMAGEHEIGHT_OFFSET	16
40 #define SMS_IMAGEWIDTH_OFFSET	0
41 #define SMS_PH_OFFSET		8
42 #define SMS_PW_OFFSET		4
43 #define SMS_PS_OFFSET		0
44 
45 /* bitmap of reserved contexts */
46 static unsigned long ctx_map;
47 
48 struct vrfb_ctx {
49 	u32 base;
50 	u32 physical_ba;
51 	u32 control;
52 	u32 size;
53 };
54 
55 static DEFINE_MUTEX(ctx_lock);
56 
57 /*
58  * Access to this happens from client drivers or the PM core after wake-up.
59  * For the first case we require locking at the driver level, for the second
60  * we don't need locking, since no drivers will run until after the wake-up
61  * has finished.
62  */
63 
64 static void __iomem *vrfb_base;
65 
66 static int num_ctxs;
67 static struct vrfb_ctx *ctxs;
68 
69 static bool vrfb_loaded;
70 
71 static void omap2_sms_write_rot_control(u32 val, unsigned ctx)
72 {
73 	__raw_writel(val, vrfb_base + SMS_ROT_CONTROL(ctx));
74 }
75 
76 static void omap2_sms_write_rot_size(u32 val, unsigned ctx)
77 {
78 	__raw_writel(val, vrfb_base + SMS_ROT_SIZE(ctx));
79 }
80 
81 static void omap2_sms_write_rot_physical_ba(u32 val, unsigned ctx)
82 {
83 	__raw_writel(val, vrfb_base + SMS_ROT_PHYSICAL_BA(ctx));
84 }
85 
86 static inline void restore_hw_context(int ctx)
87 {
88 	omap2_sms_write_rot_control(ctxs[ctx].control, ctx);
89 	omap2_sms_write_rot_size(ctxs[ctx].size, ctx);
90 	omap2_sms_write_rot_physical_ba(ctxs[ctx].physical_ba, ctx);
91 }
92 
93 static u32 get_image_width_roundup(u16 width, u8 bytespp)
94 {
95 	unsigned long stride = width * bytespp;
96 	unsigned long ceil_pages_per_stride = (stride / VRFB_PAGE_WIDTH) +
97 		(stride % VRFB_PAGE_WIDTH != 0);
98 
99 	return ceil_pages_per_stride * VRFB_PAGE_WIDTH / bytespp;
100 }
101 
102 /*
103  * This the extra space needed in the VRFB physical area for VRFB to safely wrap
104  * any memory accesses to the invisible part of the virtual view to the physical
105  * area.
106  */
107 static inline u32 get_extra_physical_size(u16 image_width_roundup, u8 bytespp)
108 {
109 	return (OMAP_VRFB_LINE_LEN - image_width_roundup) * VRFB_PAGE_HEIGHT *
110 		bytespp;
111 }
112 
113 void omap_vrfb_restore_context(void)
114 {
115 	int i;
116 	unsigned long map = ctx_map;
117 
118 	for (i = ffs(map); i; i = ffs(map)) {
119 		/* i=1..32 */
120 		i--;
121 		map &= ~(1 << i);
122 		restore_hw_context(i);
123 	}
124 }
125 
126 void omap_vrfb_adjust_size(u16 *width, u16 *height,
127 		u8 bytespp)
128 {
129 	*width = ALIGN(*width * bytespp, VRFB_PAGE_WIDTH) / bytespp;
130 	*height = ALIGN(*height, VRFB_PAGE_HEIGHT);
131 }
132 EXPORT_SYMBOL(omap_vrfb_adjust_size);
133 
134 u32 omap_vrfb_min_phys_size(u16 width, u16 height, u8 bytespp)
135 {
136 	unsigned long image_width_roundup = get_image_width_roundup(width,
137 		bytespp);
138 
139 	if (image_width_roundup > OMAP_VRFB_LINE_LEN)
140 		return 0;
141 
142 	return (width * height * bytespp) + get_extra_physical_size(
143 		image_width_roundup, bytespp);
144 }
145 EXPORT_SYMBOL(omap_vrfb_min_phys_size);
146 
147 u16 omap_vrfb_max_height(u32 phys_size, u16 width, u8 bytespp)
148 {
149 	unsigned long image_width_roundup = get_image_width_roundup(width,
150 		bytespp);
151 	unsigned long height;
152 	unsigned long extra;
153 
154 	if (image_width_roundup > OMAP_VRFB_LINE_LEN)
155 		return 0;
156 
157 	extra = get_extra_physical_size(image_width_roundup, bytespp);
158 
159 	if (phys_size < extra)
160 		return 0;
161 
162 	height = (phys_size - extra) / (width * bytespp);
163 
164 	/* Virtual views provided by VRFB are limited to 2048x2048. */
165 	return min_t(unsigned long, height, 2048);
166 }
167 EXPORT_SYMBOL(omap_vrfb_max_height);
168 
169 void omap_vrfb_setup(struct vrfb *vrfb, unsigned long paddr,
170 		u16 width, u16 height,
171 		unsigned bytespp, bool yuv_mode)
172 {
173 	unsigned pixel_size_exp;
174 	u16 vrfb_width;
175 	u16 vrfb_height;
176 	u8 ctx = vrfb->context;
177 	u32 size;
178 	u32 control;
179 
180 	DBG("omapfb_set_vrfb(%d, %lx, %dx%d, %d, %d)\n", ctx, paddr,
181 			width, height, bytespp, yuv_mode);
182 
183 	/* For YUV2 and UYVY modes VRFB needs to handle pixels a bit
184 	 * differently. See TRM. */
185 	if (yuv_mode) {
186 		bytespp *= 2;
187 		width /= 2;
188 	}
189 
190 	if (bytespp == 4)
191 		pixel_size_exp = 2;
192 	else if (bytespp == 2)
193 		pixel_size_exp = 1;
194 	else {
195 		BUG();
196 		return;
197 	}
198 
199 	vrfb_width = ALIGN(width * bytespp, VRFB_PAGE_WIDTH) / bytespp;
200 	vrfb_height = ALIGN(height, VRFB_PAGE_HEIGHT);
201 
202 	DBG("vrfb w %u, h %u bytespp %d\n", vrfb_width, vrfb_height, bytespp);
203 
204 	size  = vrfb_width << SMS_IMAGEWIDTH_OFFSET;
205 	size |= vrfb_height << SMS_IMAGEHEIGHT_OFFSET;
206 
207 	control  = pixel_size_exp << SMS_PS_OFFSET;
208 	control |= VRFB_PAGE_WIDTH_EXP  << SMS_PW_OFFSET;
209 	control |= VRFB_PAGE_HEIGHT_EXP << SMS_PH_OFFSET;
210 
211 	ctxs[ctx].physical_ba = paddr;
212 	ctxs[ctx].size = size;
213 	ctxs[ctx].control = control;
214 
215 	omap2_sms_write_rot_physical_ba(paddr, ctx);
216 	omap2_sms_write_rot_size(size, ctx);
217 	omap2_sms_write_rot_control(control, ctx);
218 
219 	DBG("vrfb offset pixels %d, %d\n",
220 			vrfb_width - width, vrfb_height - height);
221 
222 	vrfb->xres = width;
223 	vrfb->yres = height;
224 	vrfb->xoffset = vrfb_width - width;
225 	vrfb->yoffset = vrfb_height - height;
226 	vrfb->bytespp = bytespp;
227 	vrfb->yuv_mode = yuv_mode;
228 }
229 EXPORT_SYMBOL(omap_vrfb_setup);
230 
231 int omap_vrfb_map_angle(struct vrfb *vrfb, u16 height, u8 rot)
232 {
233 	unsigned long size = height * OMAP_VRFB_LINE_LEN * vrfb->bytespp;
234 
235 	vrfb->vaddr[rot] = ioremap_wc(vrfb->paddr[rot], size);
236 
237 	if (!vrfb->vaddr[rot]) {
238 		printk(KERN_ERR "vrfb: ioremap failed\n");
239 		return -ENOMEM;
240 	}
241 
242 	DBG("ioremapped vrfb area %d of size %lu into %p\n", rot, size,
243 		vrfb->vaddr[rot]);
244 
245 	return 0;
246 }
247 EXPORT_SYMBOL(omap_vrfb_map_angle);
248 
249 void omap_vrfb_release_ctx(struct vrfb *vrfb)
250 {
251 	int rot;
252 	int ctx = vrfb->context;
253 
254 	if (ctx == 0xff)
255 		return;
256 
257 	DBG("release ctx %d\n", ctx);
258 
259 	mutex_lock(&ctx_lock);
260 
261 	BUG_ON(!(ctx_map & (1 << ctx)));
262 
263 	clear_bit(ctx, &ctx_map);
264 
265 	for (rot = 0; rot < 4; ++rot) {
266 		if (vrfb->paddr[rot]) {
267 			release_mem_region(vrfb->paddr[rot], OMAP_VRFB_SIZE);
268 			vrfb->paddr[rot] = 0;
269 		}
270 	}
271 
272 	vrfb->context = 0xff;
273 
274 	mutex_unlock(&ctx_lock);
275 }
276 EXPORT_SYMBOL(omap_vrfb_release_ctx);
277 
278 int omap_vrfb_request_ctx(struct vrfb *vrfb)
279 {
280 	int rot;
281 	u32 paddr;
282 	u8 ctx;
283 	int r;
284 
285 	DBG("request ctx\n");
286 
287 	mutex_lock(&ctx_lock);
288 
289 	for (ctx = 0; ctx < num_ctxs; ++ctx)
290 		if ((ctx_map & (1 << ctx)) == 0)
291 			break;
292 
293 	if (ctx == num_ctxs) {
294 		pr_err("vrfb: no free contexts\n");
295 		r = -EBUSY;
296 		goto out;
297 	}
298 
299 	DBG("found free ctx %d\n", ctx);
300 
301 	set_bit(ctx, &ctx_map);
302 
303 	memset(vrfb, 0, sizeof(*vrfb));
304 
305 	vrfb->context = ctx;
306 
307 	for (rot = 0; rot < 4; ++rot) {
308 		paddr = ctxs[ctx].base + SMS_ROT_VIRT_BASE(rot);
309 		if (!request_mem_region(paddr, OMAP_VRFB_SIZE, "vrfb")) {
310 			pr_err("vrfb: failed to reserve VRFB "
311 					"area for ctx %d, rotation %d\n",
312 					ctx, rot * 90);
313 			omap_vrfb_release_ctx(vrfb);
314 			r = -ENOMEM;
315 			goto out;
316 		}
317 
318 		vrfb->paddr[rot] = paddr;
319 
320 		DBG("VRFB %d/%d: %lx\n", ctx, rot*90, vrfb->paddr[rot]);
321 	}
322 
323 	r = 0;
324 out:
325 	mutex_unlock(&ctx_lock);
326 	return r;
327 }
328 EXPORT_SYMBOL(omap_vrfb_request_ctx);
329 
330 bool omap_vrfb_supported(void)
331 {
332 	return vrfb_loaded;
333 }
334 EXPORT_SYMBOL(omap_vrfb_supported);
335 
336 static int __init vrfb_probe(struct platform_device *pdev)
337 {
338 	struct resource *mem;
339 	int i;
340 
341 	/* first resource is the register res, the rest are vrfb contexts */
342 	vrfb_base = devm_platform_ioremap_resource(pdev, 0);
343 	if (IS_ERR(vrfb_base))
344 		return PTR_ERR(vrfb_base);
345 
346 	num_ctxs = pdev->num_resources - 1;
347 
348 	ctxs = devm_kcalloc(&pdev->dev,
349 			num_ctxs, sizeof(struct vrfb_ctx),
350 			GFP_KERNEL);
351 
352 	if (!ctxs)
353 		return -ENOMEM;
354 
355 	for (i = 0; i < num_ctxs; ++i) {
356 		mem = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
357 		if (!mem) {
358 			dev_err(&pdev->dev, "can't get vrfb ctx %d address\n",
359 					i);
360 			return -EINVAL;
361 		}
362 
363 		ctxs[i].base = mem->start;
364 	}
365 
366 	vrfb_loaded = true;
367 
368 	return 0;
369 }
370 
371 static struct platform_driver vrfb_driver = {
372 	.driver.name	= "omapvrfb",
373 };
374 builtin_platform_driver_probe(vrfb_driver, vrfb_probe);
375 
376 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
377 MODULE_DESCRIPTION("OMAP VRFB");
378 MODULE_LICENSE("GPL v2");
379