bus/pci/promotion: add Alliance VGA core stub

scripts/src/video.lua

@@ -833,6 +833,18 @@ if (VIDEOS["PC_VGA"]~=null) then
 	}
 end
 
+--------------------------------------------------
+--
+--@src/devices/video/pc_vga_ati.h,VIDEOS["PC_VGA_ALLIANCE"] = true
+--------------------------------------------------
+
+if (VIDEOS["PC_VGA_ALLIANCE"]~=null) then
+	files {
+		MAME_DIR .. "src/devices/video/pc_vga_alliance.cpp",
+		MAME_DIR .. "src/devices/video/pc_vga_alliance.h",
+	}
+end
+
 --------------------------------------------------
 --
 --@src/devices/video/pc_vga_ati.h,VIDEOS["PC_VGA_ATI"] = true

src/devices/bus/pci/promotion.cpp

@@ -73,10 +73,11 @@ void promotion3210_device::device_add_mconfig(machine_config &config)
 	screen.set_raw(XTAL(25'174'800), 900, 0, 640, 526, 0, 480);
 	screen.set_screen_update(m_vga, FUNC(vga_device::screen_update));
 
-	VGA(config, m_vga, 0);
+	PROMOTION_VGA(config, m_vga, 0);
 	m_vga->set_screen("screen");
 	// TODO: configurable between 1 and 4 MB (2x EDO slots on board)
-	m_vga->set_vram_size(4*1024*1024);
+	// Only known OEM Board (Miro) has 1MB
+	m_vga->set_vram_size(1*1024*1024);
 
 	// AT&T ATT20C408-13 PrecisionDAC
 	// Reused by ATI Mach64?
@@ -102,6 +103,7 @@ void promotion3210_device::device_reset()
 	// TODO: to be checked
 	command = 0x0000;
 	status = 0x0000;
+	command_mask = 0x23;
 
 	remap_cb();
 }

src/devices/bus/pci/promotion.h

@@ -8,7 +8,7 @@
 
 #include "pci_slot.h"
 
-#include "video/pc_vga.h"
+#include "video/pc_vga_alliance.h"
 
 
 class promotion3210_device : public pci_card_device
@@ -35,7 +35,7 @@ protected:
 
 	virtual void config_map(address_map &map) override;
 
-	required_device<vga_device> m_vga;
+	required_device<promotion_vga_device> m_vga;
 	required_memory_region m_vga_rom;
 private:
 	u8 vram_r(offs_t offset);

src/devices/video/pc_vga_alliance.cpp

@@ -0,0 +1,89 @@
+// license:BSD-3-Clause
+// copyright-holders:
+
+#include "emu.h"
+#include "pc_vga_alliance.h"
+
+#include "screen.h"
+
+#define VERBOSE (LOG_GENERAL)
+//#define LOG_OUTPUT_FUNC osd_printf_info
+#include "logmacro.h"
+
+DEFINE_DEVICE_TYPE(PROMOTION_VGA,  promotion_vga_device,  "promotion_vga",  "Alliance ProMotion VGA i/f")
+
+promotion_vga_device::promotion_vga_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
+	: svga_device(mconfig, PROMOTION_VGA, tag, owner, clock)
+{
+	m_crtc_space_config = address_space_config("crtc_regs", ENDIANNESS_LITTLE, 8, 8, 0, address_map_constructor(FUNC(promotion_vga_device::crtc_map), this));
+	m_seq_space_config = address_space_config("sequencer_regs", ENDIANNESS_LITTLE, 8, 8, 0, address_map_constructor(FUNC(promotion_vga_device::sequencer_map), this));
+	// TODO: ATT20C408-13 RAMDAC (with bit 9 of address space), BIOS does extensive signature checks at POST
+}
+
+static INPUT_PORTS_START(promotion_vga_sense)
+	PORT_START("VGA_SENSE")
+	PORT_BIT(0x01, IP_ACTIVE_LOW, IPT_UNKNOWN )
+	PORT_BIT(0x02, IP_ACTIVE_LOW, IPT_UNKNOWN )
+	PORT_BIT(0x04, IP_ACTIVE_LOW, IPT_UNKNOWN ) // read at POST
+	PORT_BIT(0x08, IP_ACTIVE_LOW, IPT_UNKNOWN )
+INPUT_PORTS_END
+
+ioport_constructor promotion_vga_device::device_input_ports() const
+{
+	return INPUT_PORTS_NAME(promotion_vga_sense);
+}
+
+void promotion_vga_device::device_start()
+{
+	svga_device::device_start();
+}
+
+void promotion_vga_device::device_reset()
+{
+	svga_device::device_reset();
+
+	m_remap_blt = 0;
+	m_remap_mem = 0;
+}
+
+// TODO: lock mechanism
+void promotion_vga_device::crtc_map(address_map &map)
+{
+	svga_device::crtc_map(map);
+	// TODO: $19-$1e for extended regs
+}
+
+// TODO: lock mechanism
+void promotion_vga_device::sequencer_map(address_map &map)
+{
+	svga_device::sequencer_map(map);
+	map(0x10, 0xff).unmaprw();
+	map(0x1b, 0x1b).lrw8(
+		NAME([this]() { return (m_remap_blt & 0x7) << 3 | (m_remap_mem & 0x7); }),
+		NAME([this] (offs_t offset, u8 data) {
+			m_remap_blt = (data >> 3) & 0x7;
+			m_remap_mem = (data >> 0) & 0x7;
+			LOG("aT1B: Remap control %02x (host blt %01x promotion %01x)\n", data, m_remap_blt, m_remap_mem);
+		})
+	);
+}
+
+uint8_t promotion_vga_device::mem_r(offs_t offset)
+{
+	if (m_remap_mem == 1 && (offset & 0x1f800) == 0x00000)
+	{
+		LOG("aT Ext Reg: [%03x] R\n", offset );
+		return 0xff;
+	}
+	return svga_device::mem_r(offset);
+}
+
+void promotion_vga_device::mem_w(offs_t offset, uint8_t data)
+{
+	if (m_remap_mem == 1 && (offset & 0x1f800) == 0x00000)
+	{
+		LOG("aT Ext Reg: [%03x] W %02x\n", offset, data );
+		return;
+	}
+	svga_device::mem_w(offset, data);
+}

src/devices/video/pc_vga_alliance.h

@@ -0,0 +1,40 @@
+// license:BSD-3-Clause
+// copyright-holders:
+
+#ifndef MAME_VIDEO_PC_VGA_PROMOTION_H
+#define MAME_VIDEO_PC_VGA_PROMOTION_H
+
+#pragma once
+
+#include "video/pc_vga.h"
+
+#include "screen.h"
+
+
+class promotion_vga_device :  public svga_device
+{
+public:
+	static constexpr feature_type imperfect_features() { return feature::GRAPHICS; }
+
+	promotion_vga_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
+
+	virtual uint8_t mem_r(offs_t offset) override;
+	virtual void mem_w(offs_t offset, uint8_t data) override;
+
+protected:
+	virtual void device_start() override;
+	virtual void device_reset() override;
+
+	virtual void crtc_map(address_map &map) override;
+	virtual void sequencer_map(address_map &map) override;
+
+	virtual ioport_constructor device_input_ports() const override;
+
+private:
+	u8 m_remap_blt = 0;
+	u8 m_remap_mem = 0;
+};
+
+DECLARE_DEVICE_TYPE(PROMOTION_VGA, promotion_vga_device)
+
+#endif // MAME_VIDEO_PC_VGA_PROMOTION_H