xref: /linux/drivers/video/fbdev/omap2/omapfb/vrfb.c (revision 746680ec6696585e30db3e18c93a63df9cbec39c)
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/export.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/ioport.h>
16 #include <linux/io.h>
17 #include <linux/bitops.h>
18 #include <linux/mutex.h>
19 #include <linux/platform_device.h>
20 
21 #include <video/omapvrfb.h>
22 
23 #ifdef DEBUG
24 #define DBG(format, ...) pr_debug("VRFB: " format, ## __VA_ARGS__)
25 #else
26 #define DBG(format, ...)
27 #endif
28 
29 #define SMS_ROT_CONTROL(context)	(0x0 + 0x10 * context)
30 #define SMS_ROT_SIZE(context)		(0x4 + 0x10 * context)
31 #define SMS_ROT_PHYSICAL_BA(context)	(0x8 + 0x10 * context)
32 #define SMS_ROT_VIRT_BASE(rot)		(0x1000000 * (rot))
33 
34 #define OMAP_VRFB_SIZE			(2048 * 2048 * 4)
35 
36 #define VRFB_PAGE_WIDTH_EXP	5 /* Assuming SDRAM pagesize= 1024 */
37 #define VRFB_PAGE_HEIGHT_EXP	5 /* 1024 = 2^5 * 2^5 */
38 #define VRFB_PAGE_WIDTH		(1 << VRFB_PAGE_WIDTH_EXP)
39 #define VRFB_PAGE_HEIGHT	(1 << VRFB_PAGE_HEIGHT_EXP)
40 #define SMS_IMAGEHEIGHT_OFFSET	16
41 #define SMS_IMAGEWIDTH_OFFSET	0
42 #define SMS_PH_OFFSET		8
43 #define SMS_PW_OFFSET		4
44 #define SMS_PS_OFFSET		0
45 
46 /* bitmap of reserved contexts */
47 static unsigned long ctx_map;
48 
49 struct vrfb_ctx {
50 	u32 base;
51 	u32 physical_ba;
52 	u32 control;
53 	u32 size;
54 };
55 
56 static DEFINE_MUTEX(ctx_lock);
57 
58 /*
59  * Access to this happens from client drivers or the PM core after wake-up.
60  * For the first case we require locking at the driver level, for the second
61  * we don't need locking, since no drivers will run until after the wake-up
62  * has finished.
63  */
64 
65 static void __iomem *vrfb_base;
66 
67 static int num_ctxs;
68 static struct vrfb_ctx *ctxs;
69 
70 static bool vrfb_loaded;
71 
72 static void omap2_sms_write_rot_control(u32 val, unsigned ctx)
73 {
74 	__raw_writel(val, vrfb_base + SMS_ROT_CONTROL(ctx));
75 }
76 
77 static void omap2_sms_write_rot_size(u32 val, unsigned ctx)
78 {
79 	__raw_writel(val, vrfb_base + SMS_ROT_SIZE(ctx));
80 }
81 
82 static void omap2_sms_write_rot_physical_ba(u32 val, unsigned ctx)
83 {
84 	__raw_writel(val, vrfb_base + SMS_ROT_PHYSICAL_BA(ctx));
85 }
86 
87 static inline void restore_hw_context(int ctx)
88 {
89 	omap2_sms_write_rot_control(ctxs[ctx].control, ctx);
90 	omap2_sms_write_rot_size(ctxs[ctx].size, ctx);
91 	omap2_sms_write_rot_physical_ba(ctxs[ctx].physical_ba, ctx);
92 }
93 
94 static u32 get_image_width_roundup(u16 width, u8 bytespp)
95 {
96 	unsigned long stride = width * bytespp;
97 	unsigned long ceil_pages_per_stride = (stride / VRFB_PAGE_WIDTH) +
98 		(stride % VRFB_PAGE_WIDTH != 0);
99 
100 	return ceil_pages_per_stride * VRFB_PAGE_WIDTH / bytespp;
101 }
102 
103 /*
104  * This the extra space needed in the VRFB physical area for VRFB to safely wrap
105  * any memory accesses to the invisible part of the virtual view to the physical
106  * area.
107  */
108 static inline u32 get_extra_physical_size(u16 image_width_roundup, u8 bytespp)
109 {
110 	return (OMAP_VRFB_LINE_LEN - image_width_roundup) * VRFB_PAGE_HEIGHT *
111 		bytespp;
112 }
113 
114 void omap_vrfb_restore_context(void)
115 {
116 	int i;
117 	unsigned long map = ctx_map;
118 
119 	for (i = ffs(map); i; i = ffs(map)) {
120 		/* i=1..32 */
121 		i--;
122 		map &= ~(1 << i);
123 		restore_hw_context(i);
124 	}
125 }
126 
127 void omap_vrfb_adjust_size(u16 *width, u16 *height,
128 		u8 bytespp)
129 {
130 	*width = ALIGN(*width * bytespp, VRFB_PAGE_WIDTH) / bytespp;
131 	*height = ALIGN(*height, VRFB_PAGE_HEIGHT);
132 }
133 EXPORT_SYMBOL(omap_vrfb_adjust_size);
134 
135 u32 omap_vrfb_min_phys_size(u16 width, u16 height, u8 bytespp)
136 {
137 	unsigned long image_width_roundup = get_image_width_roundup(width,
138 		bytespp);
139 
140 	if (image_width_roundup > OMAP_VRFB_LINE_LEN)
141 		return 0;
142 
143 	return (width * height * bytespp) + get_extra_physical_size(
144 		image_width_roundup, bytespp);
145 }
146 EXPORT_SYMBOL(omap_vrfb_min_phys_size);
147 
148 u16 omap_vrfb_max_height(u32 phys_size, u16 width, u8 bytespp)
149 {
150 	unsigned long image_width_roundup = get_image_width_roundup(width,
151 		bytespp);
152 	unsigned long height;
153 	unsigned long extra;
154 
155 	if (image_width_roundup > OMAP_VRFB_LINE_LEN)
156 		return 0;
157 
158 	extra = get_extra_physical_size(image_width_roundup, bytespp);
159 
160 	if (phys_size < extra)
161 		return 0;
162 
163 	height = (phys_size - extra) / (width * bytespp);
164 
165 	/* Virtual views provided by VRFB are limited to 2048x2048. */
166 	return min_t(unsigned long, height, 2048);
167 }
168 EXPORT_SYMBOL(omap_vrfb_max_height);
169 
170 void omap_vrfb_setup(struct vrfb *vrfb, unsigned long paddr,
171 		u16 width, u16 height,
172 		unsigned bytespp, bool yuv_mode)
173 {
174 	unsigned pixel_size_exp;
175 	u16 vrfb_width;
176 	u16 vrfb_height;
177 	u8 ctx = vrfb->context;
178 	u32 size;
179 	u32 control;
180 
181 	DBG("omapfb_set_vrfb(%d, %lx, %dx%d, %d, %d)\n", ctx, paddr,
182 			width, height, bytespp, yuv_mode);
183 
184 	/* For YUV2 and UYVY modes VRFB needs to handle pixels a bit
185 	 * differently. See TRM. */
186 	if (yuv_mode) {
187 		bytespp *= 2;
188 		width /= 2;
189 	}
190 
191 	if (bytespp == 4)
192 		pixel_size_exp = 2;
193 	else if (bytespp == 2)
194 		pixel_size_exp = 1;
195 	else {
196 		BUG();
197 		return;
198 	}
199 
200 	vrfb_width = ALIGN(width * bytespp, VRFB_PAGE_WIDTH) / bytespp;
201 	vrfb_height = ALIGN(height, VRFB_PAGE_HEIGHT);
202 
203 	DBG("vrfb w %u, h %u bytespp %d\n", vrfb_width, vrfb_height, bytespp);
204 
205 	size  = vrfb_width << SMS_IMAGEWIDTH_OFFSET;
206 	size |= vrfb_height << SMS_IMAGEHEIGHT_OFFSET;
207 
208 	control  = pixel_size_exp << SMS_PS_OFFSET;
209 	control |= VRFB_PAGE_WIDTH_EXP  << SMS_PW_OFFSET;
210 	control |= VRFB_PAGE_HEIGHT_EXP << SMS_PH_OFFSET;
211 
212 	ctxs[ctx].physical_ba = paddr;
213 	ctxs[ctx].size = size;
214 	ctxs[ctx].control = control;
215 
216 	omap2_sms_write_rot_physical_ba(paddr, ctx);
217 	omap2_sms_write_rot_size(size, ctx);
218 	omap2_sms_write_rot_control(control, ctx);
219 
220 	DBG("vrfb offset pixels %d, %d\n",
221 			vrfb_width - width, vrfb_height - height);
222 
223 	vrfb->xres = width;
224 	vrfb->yres = height;
225 	vrfb->xoffset = vrfb_width - width;
226 	vrfb->yoffset = vrfb_height - height;
227 	vrfb->bytespp = bytespp;
228 	vrfb->yuv_mode = yuv_mode;
229 }
230 EXPORT_SYMBOL(omap_vrfb_setup);
231 
232 int omap_vrfb_map_angle(struct vrfb *vrfb, u16 height, u8 rot)
233 {
234 	unsigned long size = height * OMAP_VRFB_LINE_LEN * vrfb->bytespp;
235 
236 	vrfb->vaddr[rot] = ioremap_wc(vrfb->paddr[rot], size);
237 
238 	if (!vrfb->vaddr[rot]) {
239 		printk(KERN_ERR "vrfb: ioremap failed\n");
240 		return -ENOMEM;
241 	}
242 
243 	DBG("ioremapped vrfb area %d of size %lu into %p\n", rot, size,
244 		vrfb->vaddr[rot]);
245 
246 	return 0;
247 }
248 EXPORT_SYMBOL(omap_vrfb_map_angle);
249 
250 void omap_vrfb_release_ctx(struct vrfb *vrfb)
251 {
252 	int rot;
253 	int ctx = vrfb->context;
254 
255 	if (ctx == 0xff)
256 		return;
257 
258 	DBG("release ctx %d\n", ctx);
259 
260 	mutex_lock(&ctx_lock);
261 
262 	BUG_ON(!(ctx_map & (1 << ctx)));
263 
264 	clear_bit(ctx, &ctx_map);
265 
266 	for (rot = 0; rot < 4; ++rot) {
267 		if (vrfb->paddr[rot]) {
268 			release_mem_region(vrfb->paddr[rot], OMAP_VRFB_SIZE);
269 			vrfb->paddr[rot] = 0;
270 		}
271 	}
272 
273 	vrfb->context = 0xff;
274 
275 	mutex_unlock(&ctx_lock);
276 }
277 EXPORT_SYMBOL(omap_vrfb_release_ctx);
278 
279 int omap_vrfb_request_ctx(struct vrfb *vrfb)
280 {
281 	int rot;
282 	u32 paddr;
283 	u8 ctx;
284 	int r;
285 
286 	DBG("request ctx\n");
287 
288 	mutex_lock(&ctx_lock);
289 
290 	for (ctx = 0; ctx < num_ctxs; ++ctx)
291 		if ((ctx_map & (1 << ctx)) == 0)
292 			break;
293 
294 	if (ctx == num_ctxs) {
295 		pr_err("vrfb: no free contexts\n");
296 		r = -EBUSY;
297 		goto out;
298 	}
299 
300 	DBG("found free ctx %d\n", ctx);
301 
302 	set_bit(ctx, &ctx_map);
303 
304 	memset(vrfb, 0, sizeof(*vrfb));
305 
306 	vrfb->context = ctx;
307 
308 	for (rot = 0; rot < 4; ++rot) {
309 		paddr = ctxs[ctx].base + SMS_ROT_VIRT_BASE(rot);
310 		if (!request_mem_region(paddr, OMAP_VRFB_SIZE, "vrfb")) {
311 			pr_err("vrfb: failed to reserve VRFB "
312 					"area for ctx %d, rotation %d\n",
313 					ctx, rot * 90);
314 			omap_vrfb_release_ctx(vrfb);
315 			r = -ENOMEM;
316 			goto out;
317 		}
318 
319 		vrfb->paddr[rot] = paddr;
320 
321 		DBG("VRFB %d/%d: %lx\n", ctx, rot*90, vrfb->paddr[rot]);
322 	}
323 
324 	r = 0;
325 out:
326 	mutex_unlock(&ctx_lock);
327 	return r;
328 }
329 EXPORT_SYMBOL(omap_vrfb_request_ctx);
330 
331 bool omap_vrfb_supported(void)
332 {
333 	return vrfb_loaded;
334 }
335 EXPORT_SYMBOL(omap_vrfb_supported);
336 
337 static int __init vrfb_probe(struct platform_device *pdev)
338 {
339 	struct resource *mem;
340 	int i;
341 
342 	/* first resource is the register res, the rest are vrfb contexts */
343 	vrfb_base = devm_platform_ioremap_resource(pdev, 0);
344 	if (IS_ERR(vrfb_base))
345 		return PTR_ERR(vrfb_base);
346 
347 	num_ctxs = pdev->num_resources - 1;
348 
349 	ctxs = devm_kcalloc(&pdev->dev,
350 			num_ctxs, sizeof(struct vrfb_ctx),
351 			GFP_KERNEL);
352 
353 	if (!ctxs)
354 		return -ENOMEM;
355 
356 	for (i = 0; i < num_ctxs; ++i) {
357 		mem = platform_get_resource(pdev, IORESOURCE_MEM, 1 + i);
358 		if (!mem) {
359 			dev_err(&pdev->dev, "can't get vrfb ctx %d address\n",
360 					i);
361 			return -EINVAL;
362 		}
363 
364 		ctxs[i].base = mem->start;
365 	}
366 
367 	vrfb_loaded = true;
368 
369 	return 0;
370 }
371 
372 static struct platform_driver vrfb_driver = {
373 	.driver.name	= "omapvrfb",
374 };
375 builtin_platform_driver_probe(vrfb_driver, vrfb_probe);
376 
377 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
378 MODULE_DESCRIPTION("OMAP VRFB");
379 MODULE_LICENSE("GPL v2");
380