/* * linux/drivers/video/bt431.h * * Copyright 2003 Thiemo Seufer <seufer@csv.ica.uni-stuttgart.de> * * This file is subject to the terms and conditions of the GNU General * Public License. See the file COPYING in the main directory of this * archive for more details. */ #include <linux/types.h> #include <asm/system.h> /* * Bt431 cursor generator registers, 32-bit aligned. * Two twin Bt431 are used on the DECstation's PMAG-AA. */ struct bt431_regs { volatile u16 addr_lo; u16 pad0; volatile u16 addr_hi; u16 pad1; volatile u16 addr_cmap; u16 pad2; volatile u16 addr_reg; u16 pad3; }; static inline u16 bt431_set_value(u8 val) { return ((val << 8) | (val & 0xff)) & 0xffff; } static inline u8 bt431_get_value(u16 val) { return val & 0xff; } /* * Additional registers addressed indirectly. */ #define BT431_REG_CMD 0x0000 #define BT431_REG_CXLO 0x0001 #define BT431_REG_CXHI 0x0002 #define BT431_REG_CYLO 0x0003 #define BT431_REG_CYHI 0x0004 #define BT431_REG_WXLO 0x0005 #define BT431_REG_WXHI 0x0006 #define BT431_REG_WYLO 0x0007 #define BT431_REG_WYHI 0x0008 #define BT431_REG_WWLO 0x0009 #define BT431_REG_WWHI 0x000a #define BT431_REG_WHLO 0x000b #define BT431_REG_WHHI 0x000c #define BT431_REG_CRAM_BASE 0x0000 #define BT431_REG_CRAM_END 0x01ff /* * Command register. */ #define BT431_CMD_CURS_ENABLE 0x40 #define BT431_CMD_XHAIR_ENABLE 0x20 #define BT431_CMD_OR_CURSORS 0x10 #define BT431_CMD_AND_CURSORS 0x00 #define BT431_CMD_1_1_MUX 0x00 #define BT431_CMD_4_1_MUX 0x04 #define BT431_CMD_5_1_MUX 0x08 #define BT431_CMD_xxx_MUX 0x0c #define BT431_CMD_THICK_1 0x00 #define BT431_CMD_THICK_3 0x01 #define BT431_CMD_THICK_5 0x02 #define BT431_CMD_THICK_7 0x03 static inline void bt431_select_reg(struct bt431_regs *regs, int ir) { /* * The compiler splits the write in two bytes without these * helper variables. */ volatile u16 *lo = &(regs->addr_lo); volatile u16 *hi = &(regs->addr_hi); mb(); *lo = bt431_set_value(ir & 0xff); wmb(); *hi = bt431_set_value((ir >> 8) & 0xff); } /* Autoincrement read/write. */ static inline u8 bt431_read_reg_inc(struct bt431_regs *regs) { /* * The compiler splits the write in two bytes without the * helper variable. */ volatile u16 *r = &(regs->addr_reg); mb(); return bt431_get_value(*r); } static inline void bt431_write_reg_inc(struct bt431_regs *regs, u8 value) { /* * The compiler splits the write in two bytes without the * helper variable. */ volatile u16 *r = &(regs->addr_reg); mb(); *r = bt431_set_value(value); } static inline u8 bt431_read_reg(struct bt431_regs *regs, int ir) { bt431_select_reg(regs, ir); return bt431_read_reg_inc(regs); } static inline void bt431_write_reg(struct bt431_regs *regs, int ir, u8 value) { bt431_select_reg(regs, ir); bt431_write_reg_inc(regs, value); } /* Autoincremented read/write for the cursor map. */ static inline u16 bt431_read_cmap_inc(struct bt431_regs *regs) { /* * The compiler splits the write in two bytes without the * helper variable. */ volatile u16 *r = &(regs->addr_cmap); mb(); return *r; } static inline void bt431_write_cmap_inc(struct bt431_regs *regs, u16 value) { /* * The compiler splits the write in two bytes without the * helper variable. */ volatile u16 *r = &(regs->addr_cmap); mb(); *r = value; } static inline u16 bt431_read_cmap(struct bt431_regs *regs, int cr) { bt431_select_reg(regs, cr); return bt431_read_cmap_inc(regs); } static inline void bt431_write_cmap(struct bt431_regs *regs, int cr, u16 value) { bt431_select_reg(regs, cr); bt431_write_cmap_inc(regs, value); } static inline void bt431_enable_cursor(struct bt431_regs *regs) { bt431_write_reg(regs, BT431_REG_CMD, BT431_CMD_CURS_ENABLE | BT431_CMD_OR_CURSORS | BT431_CMD_4_1_MUX | BT431_CMD_THICK_1); } static inline void bt431_erase_cursor(struct bt431_regs *regs) { bt431_write_reg(regs, BT431_REG_CMD, BT431_CMD_4_1_MUX); } static inline void bt431_position_cursor(struct bt431_regs *regs, u16 x, u16 y) { /* * Magic from the MACH sources. * * Cx = x + D + H - P * P = 37 if 1:1, 52 if 4:1, 57 if 5:1 * D = pixel skew between outdata and external data * H = pixels between HSYNCH falling and active video * * Cy = y + V - 32 * V = scanlines between HSYNCH falling, two or more * clocks after VSYNCH falling, and active video */ x += 412 - 52; y += 68 - 32; /* Use autoincrement. */ bt431_select_reg(regs, BT431_REG_CXLO); bt431_write_reg_inc(regs, x & 0xff); /* BT431_REG_CXLO */ bt431_write_reg_inc(regs, (x >> 8) & 0x0f); /* BT431_REG_CXHI */ bt431_write_reg_inc(regs, y & 0xff); /* BT431_REG_CYLO */ bt431_write_reg_inc(regs, (y >> 8) & 0x0f); /* BT431_REG_CYHI */ } static inline void bt431_set_font(struct bt431_regs *regs, u8 fgc, u16 width, u16 height) { int i; u16 fgp = fgc ? 0xffff : 0x0000; u16 bgp = fgc ? 0x0000 : 0xffff; bt431_select_reg(regs, BT431_REG_CRAM_BASE); for (i = BT431_REG_CRAM_BASE; i <= BT431_REG_CRAM_END; i++) { u16 value; if (height << 6 <= i << 3) value = bgp; else if (width <= i % 8 << 3) value = bgp; else if (((width >> 3) & 0xffff) > i % 8) value = fgp; else value = fgp & ~(bgp << (width % 8 << 1)); bt431_write_cmap_inc(regs, value); } } static inline void bt431_init_cursor(struct bt431_regs *regs) { /* no crosshair window */ bt431_select_reg(regs, BT431_REG_WXLO); bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WXLO */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WXHI */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WYLO */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WYHI */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WWLO */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WWHI */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WHLO */ bt431_write_reg_inc(regs, 0x00); /* BT431_REG_WHHI */ }