xref: /linux/drivers/media/pci/bt8xx/btcx-risc.c (revision d2912cb15bdda8ba4a5dd73396ad62641af2f520)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 
4     btcx-risc.c
5 
6     bt848/bt878/cx2388x risc code generator.
7 
8     (c) 2000-03 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
9 
10 
11 */
12 
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/pci.h>
18 #include <linux/interrupt.h>
19 #include <linux/videodev2.h>
20 #include <asm/page.h>
21 #include <asm/pgtable.h>
22 
23 #include "btcx-risc.h"
24 
25 static unsigned int btcx_debug;
26 module_param(btcx_debug, int, 0644);
27 MODULE_PARM_DESC(btcx_debug,"debug messages, default is 0 (no)");
28 
29 #define dprintk(fmt, arg...) do {				\
30 	if (btcx_debug)						\
31 		printk(KERN_DEBUG pr_fmt("%s: " fmt),		\
32 		       __func__, ##arg);			\
33 } while (0)
34 
35 
36 /* ---------------------------------------------------------- */
37 /* allocate/free risc memory                                  */
38 
39 static int memcnt;
40 
41 void btcx_riscmem_free(struct pci_dev *pci,
42 		       struct btcx_riscmem *risc)
43 {
44 	if (NULL == risc->cpu)
45 		return;
46 
47 	memcnt--;
48 	dprintk("btcx: riscmem free [%d] dma=%lx\n",
49 		memcnt, (unsigned long)risc->dma);
50 
51 	pci_free_consistent(pci, risc->size, risc->cpu, risc->dma);
52 	memset(risc,0,sizeof(*risc));
53 }
54 
55 int btcx_riscmem_alloc(struct pci_dev *pci,
56 		       struct btcx_riscmem *risc,
57 		       unsigned int size)
58 {
59 	__le32 *cpu;
60 	dma_addr_t dma = 0;
61 
62 	if (NULL != risc->cpu && risc->size < size)
63 		btcx_riscmem_free(pci,risc);
64 	if (NULL == risc->cpu) {
65 		cpu = pci_alloc_consistent(pci, size, &dma);
66 		if (NULL == cpu)
67 			return -ENOMEM;
68 		risc->cpu  = cpu;
69 		risc->dma  = dma;
70 		risc->size = size;
71 
72 		memcnt++;
73 		dprintk("btcx: riscmem alloc [%d] dma=%lx cpu=%p size=%d\n",
74 			memcnt, (unsigned long)dma, cpu, size);
75 	}
76 	memset(risc->cpu,0,risc->size);
77 	return 0;
78 }
79 
80 /* ---------------------------------------------------------- */
81 /* screen overlay helpers                                     */
82 
83 int
84 btcx_screen_clips(int swidth, int sheight, struct v4l2_rect *win,
85 		  struct v4l2_clip *clips, unsigned int n)
86 {
87 	if (win->left < 0) {
88 		/* left */
89 		clips[n].c.left = 0;
90 		clips[n].c.top = 0;
91 		clips[n].c.width  = -win->left;
92 		clips[n].c.height = win->height;
93 		n++;
94 	}
95 	if (win->left + win->width > swidth) {
96 		/* right */
97 		clips[n].c.left   = swidth - win->left;
98 		clips[n].c.top    = 0;
99 		clips[n].c.width  = win->width - clips[n].c.left;
100 		clips[n].c.height = win->height;
101 		n++;
102 	}
103 	if (win->top < 0) {
104 		/* top */
105 		clips[n].c.left = 0;
106 		clips[n].c.top = 0;
107 		clips[n].c.width  = win->width;
108 		clips[n].c.height = -win->top;
109 		n++;
110 	}
111 	if (win->top + win->height > sheight) {
112 		/* bottom */
113 		clips[n].c.left = 0;
114 		clips[n].c.top = sheight - win->top;
115 		clips[n].c.width  = win->width;
116 		clips[n].c.height = win->height - clips[n].c.top;
117 		n++;
118 	}
119 	return n;
120 }
121 
122 int
123 btcx_align(struct v4l2_rect *win, struct v4l2_clip *clips, unsigned int n, int mask)
124 {
125 	s32 nx,nw,dx;
126 	unsigned int i;
127 
128 	/* fixup window */
129 	nx = (win->left + mask) & ~mask;
130 	nw = (win->width) & ~mask;
131 	if (nx + nw > win->left + win->width)
132 		nw -= mask+1;
133 	dx = nx - win->left;
134 	win->left  = nx;
135 	win->width = nw;
136 	dprintk("btcx: window align %dx%d+%d+%d [dx=%d]\n",
137 	       win->width, win->height, win->left, win->top, dx);
138 
139 	/* fixup clips */
140 	for (i = 0; i < n; i++) {
141 		nx = (clips[i].c.left-dx) & ~mask;
142 		nw = (clips[i].c.width) & ~mask;
143 		if (nx + nw < clips[i].c.left-dx + clips[i].c.width)
144 			nw += mask+1;
145 		clips[i].c.left  = nx;
146 		clips[i].c.width = nw;
147 		dprintk("btcx:   clip align %dx%d+%d+%d\n",
148 		       clips[i].c.width, clips[i].c.height,
149 		       clips[i].c.left, clips[i].c.top);
150 	}
151 	return 0;
152 }
153 
154 void
155 btcx_sort_clips(struct v4l2_clip *clips, unsigned int nclips)
156 {
157 	int i,j,n;
158 
159 	if (nclips < 2)
160 		return;
161 	for (i = nclips-2; i >= 0; i--) {
162 		for (n = 0, j = 0; j <= i; j++) {
163 			if (clips[j].c.left > clips[j+1].c.left) {
164 				swap(clips[j], clips[j + 1]);
165 				n++;
166 			}
167 		}
168 		if (0 == n)
169 			break;
170 	}
171 }
172 
173 void
174 btcx_calc_skips(int line, int width, int *maxy,
175 		struct btcx_skiplist *skips, unsigned int *nskips,
176 		const struct v4l2_clip *clips, unsigned int nclips)
177 {
178 	unsigned int clip,skip;
179 	int end, maxline;
180 
181 	skip=0;
182 	maxline = 9999;
183 	for (clip = 0; clip < nclips; clip++) {
184 
185 		/* sanity checks */
186 		if (clips[clip].c.left + clips[clip].c.width <= 0)
187 			continue;
188 		if (clips[clip].c.left > (signed)width)
189 			break;
190 
191 		/* vertical range */
192 		if (line > clips[clip].c.top+clips[clip].c.height-1)
193 			continue;
194 		if (line < clips[clip].c.top) {
195 			if (maxline > clips[clip].c.top-1)
196 				maxline = clips[clip].c.top-1;
197 			continue;
198 		}
199 		if (maxline > clips[clip].c.top+clips[clip].c.height-1)
200 			maxline = clips[clip].c.top+clips[clip].c.height-1;
201 
202 		/* horizontal range */
203 		if (0 == skip || clips[clip].c.left > skips[skip-1].end) {
204 			/* new one */
205 			skips[skip].start = clips[clip].c.left;
206 			if (skips[skip].start < 0)
207 				skips[skip].start = 0;
208 			skips[skip].end = clips[clip].c.left + clips[clip].c.width;
209 			if (skips[skip].end > width)
210 				skips[skip].end = width;
211 			skip++;
212 		} else {
213 			/* overlaps -- expand last one */
214 			end = clips[clip].c.left + clips[clip].c.width;
215 			if (skips[skip-1].end < end)
216 				skips[skip-1].end = end;
217 			if (skips[skip-1].end > width)
218 				skips[skip-1].end = width;
219 		}
220 	}
221 	*nskips = skip;
222 	*maxy = maxline;
223 
224 	if (btcx_debug) {
225 		dprintk("btcx: skips line %d-%d:", line, maxline);
226 		for (skip = 0; skip < *nskips; skip++) {
227 			pr_cont(" %d-%d", skips[skip].start, skips[skip].end);
228 		}
229 		pr_cont("\n");
230 	}
231 }
232