dingusppc/devices/video/appleramdac.h

/*
DingusPPC - The Experimental PowerPC Macintosh emulator
Copyright (C) 2018-24 divingkatae and maximum
                      (theweirdo)     spatium

(Contact divingkatae#1017 or powermax#2286 on Discord for more info)

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

/** Definitions for the Apple RAMDAC ASICs (RaDACal & DACula). */

#ifndef APPLE_RAMDAC_H
#define APPLE_RAMDAC_H

#include <devices/common/hwcomponent.h>
#include <devices/ioctrl/macio.h>

#include <cinttypes>
#include <functional>

enum DacFlavour {
    RADACAL,
    DACULA,
};

#define DACULA_VENDOR_SIERRA    0x3C // 14.3 MHz
#define DACULA_VENDOR_OTHER     0x84 // 15 MHz

constexpr auto VIDEO_XTAL = 14318180.0f; // external crystal oscillator frequency

namespace RamdacRegs {

enum RamdacRegs : uint8_t {
    ADDRESS         = 0, // address register
    CURSOR_CLUT     = 1, // cursor palette data
    MULTI           = 2, // multipurpose section
    CLUT_DATA       = 3, // color palette data

    // multipurpose section registers (both RaDACal & DACula)
    CURSOR_POS_HI   = 0x10, // cursor position, high-order byte
    CURSOR_POS_LO   = 0x11, // cursor position, low-order byte
    MISC_CTRL       = 0x20, // miscellaneus control bits ; Dacula: read ; when 1MB VRAM then write (mode&15) else write (mode)
    DBL_BUF_CTRL    = 0x21, // double buffer control bits ; Dacula: write 4; Radical: set to 0 if using optional bank (bankb) in Open Firmware or for 2nd page in ndrv
    TEST_CTRL       = 0x22, // enable/disable DAC tests ; Dacula: write 0

    // multipurpose section registers (DACula only)
    PLL_CTRL        = 0x23, // phase locked loop control ; Dacula: if read 2 then write 3 else write 2 <-
    VIDCLK_M_SET_A  = 0x24, // M parameter for the set A ; Dacula: N2 for 2
    VIDCLK_PN_SET_A = 0x25, // P & N parameters for the set A ; Dacula: D2 for 2
    //              = 0x26, // Dacula: write 0xc6 before changing the clock
    VIDCLK_M_SET_B  = 0x27, // M parameter for the set B ; Dacula: N2 for 3 <-
    VIDCLK_PN_SET_B = 0x28, // P & N parameters for the set B ; Dacula: D2 for 3 <-
    DAC_29          = 0x29, // Dacula: linux writes 0xa6 after changing the clock ; macrom writes 0xc6
    VENDOR_ID       = 0x40, // Dacula: DAC_TYPE 0x3c or 0x84
};

}; // namespace RamdacRegs

typedef std::function<void(uint8_t index, uint8_t *colors)> GetClutEntryCallback;
typedef std::function<void(uint8_t index, uint8_t *colors)> SetClutEntryCallback;
typedef std::function<void(bool cursor_on)> CursorCtrlCallback;

class AppleRamdac : public HWComponent, public IobusDevice {
public:
    AppleRamdac(DacFlavour flavour);
    ~AppleRamdac() = default;

    uint16_t    iodev_read(uint32_t address);
    void        iodev_write(uint32_t address, uint16_t value);

    int get_clock_div();
    int get_pix_width();
    int get_dot_freq();
    uint8_t get_dbl_buf_cr() { return dbl_buf_cr; }

    void set_fb_parameters(int width, int height, uint32_t pitch) {
        this->video_width  = width;
        this->video_height = height;
        this->fb_pitch     = pitch;
    };

    void measure_hw_cursor(uint8_t *fb_ptr);
    void draw_hw_cursor(uint8_t *src_buf, uint8_t *dst_buf, int dst_pitch);

    GetClutEntryCallback get_clut_entry_cb = nullptr;
    SetClutEntryCallback set_clut_entry_cb = nullptr;
    CursorCtrlCallback   cursor_ctrl_cb    = nullptr;

protected:
    DacFlavour  flavour;
    uint8_t     dac_addr        = 0;
    uint8_t     dac_cr          = 0;
    uint8_t     dbl_buf_cr      = 0;
    uint8_t     tst_cr          = 0;
    uint16_t    cursor_xpos     = 0; // horizontal position of the cursor region
    uint16_t    cursor_ypos     = 0;
    uint16_t    cursor_height   = 0;
    uint8_t     cursor_pos_lo   = 0;
    uint8_t     clk_m[2]        = {};
    uint8_t     clk_pn[2]       = {};
    uint8_t     pll_cr          = 0;
    uint8_t     dac_vendor      = DACULA_VENDOR_SIERRA;
    uint8_t     comp_index      = 0;
    uint8_t     clut_color[3]   = {};
    uint32_t    cursor_clut[8]  = {};
    int         video_width     = 0;
    int         video_height    = 0;
    uint32_t    fb_pitch        = 0;
};

#endif // APPLE_RAMDAC_H