mach64_cursor.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  ATI Mach64 CT/VT/GT/LT Cursor Support
  4 */
  5
  6#include <linux/fb.h>
  7#include <linux/init.h>
  8#include <linux/string.h>
  9
 10#include <asm/io.h>
 11
 12#ifdef __sparc__
 13#include <asm/fbio.h>
 14#endif
 15
 16#include <video/mach64.h>
 17#include "atyfb.h"
 18
 19/*
 20 * The hardware cursor definition requires 2 bits per pixel. The
 21 * Cursor size reguardless of the visible cursor size is 64 pixels
 22 * by 64 lines. The total memory required to define the cursor is
 23 * 16 bytes / line for 64 lines or 1024 bytes of data. The data
 24 * must be in a contigiuos format. The 2 bit cursor code values are
 25 * as follows:
 26 *
 27 *	00 - pixel colour = CURSOR_CLR_0
 28 *	01 - pixel colour = CURSOR_CLR_1
 29 *	10 - pixel colour = transparent (current display pixel)
 30 *	11 - pixel colour = 1's complement of current display pixel
 31 *
 32 *	Cursor Offset        64 pixels		 Actual Displayed Area
 33 *            \_________________________/
 34 *	      |			|	|	|
 35 *	      |<--------------->|	|	|
 36 *	      | CURS_HORZ_OFFSET|	|	|
 37 *	      |			|_______|	|  64 Lines
 38 *	      |			   ^	|	|
 39 *	      |			   |	|	|
 40 *	      |		CURS_VERT_OFFSET|	|
 41 *	      |			   |	|	|
 42 *	      |____________________|____|	|
 43 *
 44 *
 45 * The Screen position of the top left corner of the displayed
 46 * cursor is specificed by CURS_HORZ_VERT_POSN. Care must be taken
 47 * when the cursor hot spot is not the top left corner and the
 48 * physical cursor position becomes negative. It will be displayed
 49 * if either the horizontal or vertical cursor position is negative
 50 *
 51 * If x becomes negative the cursor manager must adjust the CURS_HORZ_OFFSET
 52 * to a larger number and saturate CUR_HORZ_POSN to zero.
 53 *
 54 * if Y becomes negative, CUR_VERT_OFFSET must be adjusted to a larger number,
 55 * CUR_OFFSET must be adjusted to a point to the appropriate line in the cursor
 56 * definitation and CUR_VERT_POSN must be saturated to zero.
 57 */
 58
 59/* compose pixels based on mask */
 60static inline unsigned long comp(unsigned long set, unsigned long unset, unsigned long mask)
 61{
 62	return ((set ^ unset) & mask) ^ unset;
 63}
 64
 65    /*
 66     *  Hardware Cursor support.
 67     */
 68static const u8 cursor_bits_lookup[16] = {
 69	0x00, 0x40, 0x10, 0x50, 0x04, 0x44, 0x14, 0x54,
 70	0x01, 0x41, 0x11, 0x51, 0x05, 0x45, 0x15, 0x55
 71};
 72
 73static int atyfb_cursor(struct fb_info *info, struct fb_cursor *cursor)
 74{
 75	struct atyfb_par *par = (struct atyfb_par *) info->par;
 76	u16 xoff, yoff;
 77	int x, y, h;
 78
 79#ifdef __sparc__
 80	if (par->mmaped)
 81		return -EPERM;
 82#endif
 83	if (par->asleep)
 84		return -EPERM;
 85
 86	wait_for_fifo(1, par);
 87	if (cursor->enable)
 88		aty_st_le32(GEN_TEST_CNTL, aty_ld_le32(GEN_TEST_CNTL, par)
 89			    | HWCURSOR_ENABLE, par);
 90	else
 91		aty_st_le32(GEN_TEST_CNTL, aty_ld_le32(GEN_TEST_CNTL, par)
 92				& ~HWCURSOR_ENABLE, par);
 93
 94	/* set position */
 95	if (cursor->set & FB_CUR_SETPOS) {
 96		x = cursor->image.dx - cursor->hot.x - info->var.xoffset;
 97		if (x < 0) {
 98			xoff = -x;
 99			x = 0;
100		} else {
101			xoff = 0;
102		}
103
104		y = cursor->image.dy - cursor->hot.y - info->var.yoffset;
105		if (y < 0) {
106			yoff = -y;
107			y = 0;
108		} else {
109			yoff = 0;
110		}
111
112		h = cursor->image.height;
113
114		/*
115		 * In doublescan mode, the cursor location
116		 * and heigh also needs to be doubled.
117		 */
118                if (par->crtc.gen_cntl & CRTC_DBL_SCAN_EN) {
119			y<<=1;
120			h<<=1;
121		}
122		wait_for_fifo(3, par);
123		aty_st_le32(CUR_OFFSET, (info->fix.smem_len >> 3) + (yoff << 1), par);
124		aty_st_le32(CUR_HORZ_VERT_OFF,
125			    ((u32) (64 - h + yoff) << 16) | xoff, par);
126		aty_st_le32(CUR_HORZ_VERT_POSN, ((u32) y << 16) | x, par);
127	}
128
129	/* Set color map */
130	if (cursor->set & FB_CUR_SETCMAP) {
131		u32 fg_idx, bg_idx, fg, bg;
132
133		fg_idx = cursor->image.fg_color;
134		bg_idx = cursor->image.bg_color;
135
136		fg = ((info->cmap.red[fg_idx] & 0xff) << 24) |
137		     ((info->cmap.green[fg_idx] & 0xff) << 16) |
138		     ((info->cmap.blue[fg_idx] & 0xff) << 8) | 0xff;
139
140		bg = ((info->cmap.red[bg_idx] & 0xff) << 24) |
141		     ((info->cmap.green[bg_idx] & 0xff) << 16) |
142		     ((info->cmap.blue[bg_idx] & 0xff) << 8);
143
144		wait_for_fifo(2, par);
145		aty_st_le32(CUR_CLR0, bg, par);
146		aty_st_le32(CUR_CLR1, fg, par);
147	}
148
149	if (cursor->set & (FB_CUR_SETSHAPE | FB_CUR_SETIMAGE)) {
150	    u8 *src = (u8 *)cursor->image.data;
151	    u8 *msk = (u8 *)cursor->mask;
152	    u8 __iomem *dst = (u8 __iomem *)info->sprite.addr;
153	    unsigned int width = (cursor->image.width + 7) >> 3;
154	    unsigned int height = cursor->image.height;
155	    unsigned int align = info->sprite.scan_align;
156
157	    unsigned int i, j, offset;
158	    u8 m, b;
159
160	    // Clear cursor image with 1010101010...
161	    fb_memset_io(dst, 0xaa, 1024);
162
163	    offset = align - width*2;
164
165	    for (i = 0; i < height; i++) {
166		for (j = 0; j < width; j++) {
167			u16 l = 0xaaaa;
168			b = *src++;
169			m = *msk++;
170			switch (cursor->rop) {
171			case ROP_XOR:
172			    // Upper 4 bits of mask data
173			    l = cursor_bits_lookup[(b ^ m) >> 4] |
174			    // Lower 4 bits of mask
175				    (cursor_bits_lookup[(b ^ m) & 0x0f] << 8);
176			    break;
177			case ROP_COPY:
178			    // Upper 4 bits of mask data
179			    l = cursor_bits_lookup[(b & m) >> 4] |
180			    // Lower 4 bits of mask
181				    (cursor_bits_lookup[(b & m) & 0x0f] << 8);
182			    break;
183			}
184			/*
185			 * If cursor size is not a multiple of 8 characters
186			 * we must pad it with transparent pattern (0xaaaa).
187			 */
188			if ((j + 1) * 8 > cursor->image.width) {
189				l = comp(l, 0xaaaa,
190				    (1 << ((cursor->image.width & 7) * 2)) - 1);
191			}
192			fb_writeb(l & 0xff, dst++);
193			fb_writeb(l >> 8, dst++);
194		}
195		dst += offset;
196	    }
197	}
198
199	return 0;
200}
201
202int aty_init_cursor(struct fb_info *info, struct fb_ops *atyfb_ops)
203{
204	unsigned long addr;
205
206	info->fix.smem_len -= PAGE_SIZE;
207
208#ifdef __sparc__
209	addr = (unsigned long) info->screen_base - 0x800000 + info->fix.smem_len;
210	info->sprite.addr = (u8 *) addr;
211#else
212#ifdef __BIG_ENDIAN
213	addr = info->fix.smem_start - 0x800000 + info->fix.smem_len;
214	info->sprite.addr = (u8 *) ioremap(addr, 1024);
215#else
216	addr = (unsigned long) info->screen_base + info->fix.smem_len;
217	info->sprite.addr = (u8 *) addr;
218#endif
219#endif
220	if (!info->sprite.addr)
221		return -ENXIO;
222	info->sprite.size = PAGE_SIZE;
223	info->sprite.scan_align = 16;	/* Scratch pad 64 bytes wide */
224	info->sprite.buf_align = 16; 	/* and 64 lines tall. */
225	info->sprite.flags = FB_PIXMAP_IO;
226
227	atyfb_ops->fb_cursor = atyfb_cursor;
228
229	return 0;
230}
231