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 */
46static unsigned long ctx_map;
47
48struct vrfb_ctx {
49	u32 base;
50	u32 physical_ba;
51	u32 control;
52	u32 size;
53};
54
55static 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
64static void __iomem *vrfb_base;
65
66static int num_ctxs;
67static struct vrfb_ctx *ctxs;
68
69static bool vrfb_loaded;
70
71static void omap2_sms_write_rot_control(u32 val, unsigned ctx)
72{
73	__raw_writel(val, vrfb_base + SMS_ROT_CONTROL(ctx));
74}
75
76static void omap2_sms_write_rot_size(u32 val, unsigned ctx)
77{
78	__raw_writel(val, vrfb_base + SMS_ROT_SIZE(ctx));
79}
80
81static 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
86static 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
93static 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 */
107static 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
113void 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
126void 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}
132EXPORT_SYMBOL(omap_vrfb_adjust_size);
133
134u32 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}
145EXPORT_SYMBOL(omap_vrfb_min_phys_size);
146
147u16 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}
167EXPORT_SYMBOL(omap_vrfb_max_height);
168
169void 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}
229EXPORT_SYMBOL(omap_vrfb_setup);
230
231int 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}
247EXPORT_SYMBOL(omap_vrfb_map_angle);
248
249void 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}
276EXPORT_SYMBOL(omap_vrfb_release_ctx);
277
278int 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;
324out:
325	mutex_unlock(&ctx_lock);
326	return r;
327}
328EXPORT_SYMBOL(omap_vrfb_request_ctx);
329
330bool omap_vrfb_supported(void)
331{
332	return vrfb_loaded;
333}
334EXPORT_SYMBOL(omap_vrfb_supported);
335
336static 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
371static void __exit vrfb_remove(struct platform_device *pdev)
372{
373	vrfb_loaded = false;
374}
375
376static struct platform_driver vrfb_driver = {
377	.driver.name	= "omapvrfb",
378	.remove		= __exit_p(vrfb_remove),
379};
380
381module_platform_driver_probe(vrfb_driver, vrfb_probe);
382
383MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
384MODULE_DESCRIPTION("OMAP VRFB");
385MODULE_LICENSE("GPL v2");
386