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1/*2 * linux/drivers/video/bt431.h3 *4 * Copyright 2003 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de>5 * Copyright 2016 Maciej W. Rozycki <macro@linux-mips.org>6 *7 * This file is subject to the terms and conditions of the GNU General8 * Public License. See the file COPYING in the main directory of this9 * archive for more details.10 */11#include <linux/types.h>12 13#define BT431_CURSOR_SIZE 6414 15/*16 * Bt431 cursor generator registers, 32-bit aligned.17 * Two twin Bt431 are used on the DECstation's PMAG-AA.18 */19struct bt431_regs {20 volatile u16 addr_lo;21 u16 pad0;22 volatile u16 addr_hi;23 u16 pad1;24 volatile u16 addr_cmap;25 u16 pad2;26 volatile u16 addr_reg;27 u16 pad3;28};29 30static inline u16 bt431_set_value(u8 val)31{32 return ((val << 8) | (val & 0xff)) & 0xffff;33}34 35static inline u8 bt431_get_value(u16 val)36{37 return val & 0xff;38}39 40/*41 * Additional registers addressed indirectly.42 */43#define BT431_REG_CMD 0x000044#define BT431_REG_CXLO 0x000145#define BT431_REG_CXHI 0x000246#define BT431_REG_CYLO 0x000347#define BT431_REG_CYHI 0x000448#define BT431_REG_WXLO 0x000549#define BT431_REG_WXHI 0x000650#define BT431_REG_WYLO 0x000751#define BT431_REG_WYHI 0x000852#define BT431_REG_WWLO 0x000953#define BT431_REG_WWHI 0x000a54#define BT431_REG_WHLO 0x000b55#define BT431_REG_WHHI 0x000c56 57#define BT431_REG_CRAM_BASE 0x000058#define BT431_REG_CRAM_END 0x01ff59 60/*61 * Command register.62 */63#define BT431_CMD_CURS_ENABLE 0x4064#define BT431_CMD_XHAIR_ENABLE 0x2065#define BT431_CMD_OR_CURSORS 0x1066#define BT431_CMD_XOR_CURSORS 0x0067#define BT431_CMD_1_1_MUX 0x0068#define BT431_CMD_4_1_MUX 0x0469#define BT431_CMD_5_1_MUX 0x0870#define BT431_CMD_xxx_MUX 0x0c71#define BT431_CMD_THICK_1 0x0072#define BT431_CMD_THICK_3 0x0173#define BT431_CMD_THICK_5 0x0274#define BT431_CMD_THICK_7 0x0375 76static inline void bt431_select_reg(struct bt431_regs *regs, int ir)77{78 /*79 * The compiler splits the write in two bytes without these80 * helper variables.81 */82 volatile u16 *lo = &(regs->addr_lo);83 volatile u16 *hi = &(regs->addr_hi);84 85 mb();86 *lo = bt431_set_value(ir & 0xff);87 wmb();88 *hi = bt431_set_value((ir >> 8) & 0xff);89}90 91/* Autoincrement read/write. */92static inline u8 bt431_read_reg_inc(struct bt431_regs *regs)93{94 /*95 * The compiler splits the write in two bytes without the96 * helper variable.97 */98 volatile u16 *r = &(regs->addr_reg);99 100 mb();101 return bt431_get_value(*r);102}103 104static inline void bt431_write_reg_inc(struct bt431_regs *regs, u8 value)105{106 /*107 * The compiler splits the write in two bytes without the108 * helper variable.109 */110 volatile u16 *r = &(regs->addr_reg);111 112 mb();113 *r = bt431_set_value(value);114}115 116static inline u8 bt431_read_reg(struct bt431_regs *regs, int ir)117{118 bt431_select_reg(regs, ir);119 return bt431_read_reg_inc(regs);120}121 122static inline void bt431_write_reg(struct bt431_regs *regs, int ir, u8 value)123{124 bt431_select_reg(regs, ir);125 bt431_write_reg_inc(regs, value);126}127 128/* Autoincremented read/write for the cursor map. */129static inline u16 bt431_read_cmap_inc(struct bt431_regs *regs)130{131 /*132 * The compiler splits the write in two bytes without the133 * helper variable.134 */135 volatile u16 *r = &(regs->addr_cmap);136 137 mb();138 return *r;139}140 141static inline void bt431_write_cmap_inc(struct bt431_regs *regs, u16 value)142{143 /*144 * The compiler splits the write in two bytes without the145 * helper variable.146 */147 volatile u16 *r = &(regs->addr_cmap);148 149 mb();150 *r = value;151}152 153static inline u16 bt431_read_cmap(struct bt431_regs *regs, int cr)154{155 bt431_select_reg(regs, cr);156 return bt431_read_cmap_inc(regs);157}158 159static inline void bt431_write_cmap(struct bt431_regs *regs, int cr, u16 value)160{161 bt431_select_reg(regs, cr);162 bt431_write_cmap_inc(regs, value);163}164 165static inline void bt431_enable_cursor(struct bt431_regs *regs)166{167 bt431_write_reg(regs, BT431_REG_CMD,168 BT431_CMD_CURS_ENABLE | BT431_CMD_OR_CURSORS169 | BT431_CMD_4_1_MUX | BT431_CMD_THICK_1);170}171 172static inline void bt431_erase_cursor(struct bt431_regs *regs)173{174 bt431_write_reg(regs, BT431_REG_CMD, BT431_CMD_4_1_MUX);175}176 177static inline void bt431_position_cursor(struct bt431_regs *regs, u16 x, u16 y)178{179 /*180 * Magic from the MACH sources.181 *182 * Cx = x + D + H - P183 * P = 37 if 1:1, 52 if 4:1, 57 if 5:1184 * D = pixel skew between outdata and external data185 * H = pixels between HSYNCH falling and active video186 *187 * Cy = y + V - 32188 * V = scanlines between HSYNCH falling, two or more189 * clocks after VSYNCH falling, and active video190 */191 x += 412 - 52;192 y += 68 - 32;193 194 /* Use autoincrement. */195 bt431_select_reg(regs, BT431_REG_CXLO);196 bt431_write_reg_inc(regs, x & 0xff); /* BT431_REG_CXLO */197 bt431_write_reg_inc(regs, (x >> 8) & 0x0f); /* BT431_REG_CXHI */198 bt431_write_reg_inc(regs, y & 0xff); /* BT431_REG_CYLO */199 bt431_write_reg_inc(regs, (y >> 8) & 0x0f); /* BT431_REG_CYHI */200}201 202static inline void bt431_set_cursor(struct bt431_regs *regs,203 const char *data, const char *mask,204 u16 rop, u16 width, u16 height)205{206 u16 x, y;207 int i;208 209 i = 0;210 width = DIV_ROUND_UP(width, 8);211 bt431_select_reg(regs, BT431_REG_CRAM_BASE);212 for (y = 0; y < BT431_CURSOR_SIZE; y++)213 for (x = 0; x < BT431_CURSOR_SIZE / 8; x++) {214 u16 val = 0;215 216 if (y < height && x < width) {217 val = mask[i];218 if (rop == ROP_XOR)219 val = (val << 8) | (val ^ data[i]);220 else221 val = (val << 8) | (val & data[i]);222 i++;223 }224 bt431_write_cmap_inc(regs, val);225 }226}227 228static inline void bt431_init_cursor(struct bt431_regs *regs)229{230 /* no crosshair window */231 bt431_select_reg(regs, BT431_REG_WXLO);232 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WXLO */233 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WXHI */234 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WYLO */235 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WYHI */236 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WWLO */237 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WWHI */238 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WHLO */239 bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WHHI */240}241