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Added emulation of IBM 80386 Memory Expansion Adapter. PS/2 Model 80 now supports up to 12MB RAM.

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This commit is contained in:
SarahW 2017-04-18 22:14:32 +01:00
commit aeccbd8bd6
4 changed files with 144 additions and 12 deletions
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151
src/ps2_mca.c
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@ -33,6 +33,8 @@ static struct
uint8_t io_id;
mem_mapping_t shadow_mapping;
mem_mapping_t split_mapping;
mem_mapping_t expansion_mapping;
uint8_t (*planar_read)(uint16_t port);
void (*planar_write)(uint16_t port, uint8_t val);
@ -40,40 +42,73 @@ static struct
uint8_t mem_regs[3];
uint32_t split_addr;
uint8_t mem_pos_regs[8];
} ps2;
uint8_t ps2_read_shadow_ram(uint32_t addr, void *priv)
static uint8_t ps2_read_shadow_ram(uint32_t addr, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
return mem_read_ram(addr, priv);
}
uint16_t ps2_read_shadow_ramw(uint32_t addr, void *priv)
static uint16_t ps2_read_shadow_ramw(uint32_t addr, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
return mem_read_ramw(addr, priv);
}
uint32_t ps2_read_shadow_raml(uint32_t addr, void *priv)
static uint32_t ps2_read_shadow_raml(uint32_t addr, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
return mem_read_raml(addr, priv);
}
void ps2_write_shadow_ram(uint32_t addr, uint8_t val, void *priv)
static void ps2_write_shadow_ram(uint32_t addr, uint8_t val, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
mem_write_ram(addr, val, priv);
}
void ps2_write_shadow_ramw(uint32_t addr, uint16_t val, void *priv)
static void ps2_write_shadow_ramw(uint32_t addr, uint16_t val, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
mem_write_ramw(addr, val, priv);
}
void ps2_write_shadow_raml(uint32_t addr, uint32_t val, void *priv)
static void ps2_write_shadow_raml(uint32_t addr, uint32_t val, void *priv)
{
addr = (addr & 0x1ffff) + 0xe0000;
mem_write_raml(addr, val, priv);
}
static uint8_t ps2_read_split_ram(uint32_t addr, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
return mem_read_ram(addr, priv);
}
static uint16_t ps2_read_split_ramw(uint32_t addr, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
return mem_read_ramw(addr, priv);
}
static uint32_t ps2_read_split_raml(uint32_t addr, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
return mem_read_raml(addr, priv);
}
static void ps2_write_split_ram(uint32_t addr, uint8_t val, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
mem_write_ram(addr, val, priv);
}
static void ps2_write_split_ramw(uint32_t addr, uint16_t val, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
mem_write_ramw(addr, val, priv);
}
static void ps2_write_split_raml(uint32_t addr, uint32_t val, void *priv)
{
addr = (addr & 0x3ffff) + 0xa0000;
mem_write_raml(addr, val, priv);
}
#define PS2_SETUP_IO 0x80
@ -609,7 +644,7 @@ void ps2_mca_board_model_55sx_init()
static void mem_encoding_update()
{
if (ps2.split_addr >= mem_size*1024)
mem_set_mem_state(ps2.split_addr, 256 * 1024, MEM_READ_EXTERNAL | MEM_WRITE_EXTERNAL);
mem_mapping_disable(&ps2.split_mapping);
ps2.split_addr = (ps2.mem_regs[0] & 0xf) << 20;
@ -621,7 +656,7 @@ static void mem_encoding_update()
if (!(ps2.mem_regs[1] & 8))
{
if (ps2.split_addr >= mem_size*1024)
mem_set_mem_state(ps2.split_addr, 256 * 1024, MEM_READ_INTERNAL | MEM_WRITE_INTERNAL);
mem_mapping_set_addr(&ps2.split_mapping, ps2.split_addr, 256*1024);
}
}
@ -650,6 +685,24 @@ static void mem_encoding_write(uint16_t addr, uint8_t val, void *p)
mem_encoding_update();
}
static uint8_t ps2_mem_expansion_read(int port, void *p)
{
return ps2.mem_pos_regs[port & 7];
}
static void ps2_mem_expansion_write(int port, uint8_t val, void *p)
{
if (port < 0x102 || port == 0x104)
return;
ps2.mem_pos_regs[port & 7] = val;
if (ps2.mem_pos_regs[2] & 1)
mem_mapping_enable(&ps2.expansion_mapping);
else
mem_mapping_disable(&ps2.expansion_mapping);
}
void ps2_mca_board_model_80_type2_init()
{
ps2_mca_board_common_init();
@ -667,8 +720,86 @@ void ps2_mca_board_model_80_type2_init()
ps2.mem_regs[1] = 2;
if (mem_size == 2*1024)
switch (mem_size/1024)
{
case 1:
ps2.option[1] = 0x0c;
break;
case 2:
ps2.option[1] = 0x0e;
else
break;
case 3:
ps2.option[1] = 0x02;
break;
case 4:
default:
ps2.option[1] = 0x0a;
break;
}
mem_mapping_add(&ps2.split_mapping,
(mem_size+256) * 1024,
256*1024,
ps2_read_split_ram,
ps2_read_split_ramw,
ps2_read_split_raml,
ps2_write_split_ram,
ps2_write_split_ramw,
ps2_write_split_raml,
&ram[0xa0000],
MEM_MAPPING_INTERNAL,
NULL);
mem_mapping_disable(&ps2.split_mapping);
if (mem_size > 4096)
{
/* Only 4 MB supported on planar, create a memory expansion card for the rest */
mem_mapping_set_addr(&ram_high_mapping, 0x100000, 0x300000);
ps2.mem_pos_regs[0] = 0xff;
ps2.mem_pos_regs[1] = 0xfc;
switch (mem_size/1024)
{
case 5:
ps2.mem_pos_regs[4] = 0xfc;
break;
case 6:
ps2.mem_pos_regs[4] = 0xfe;
break;
case 7:
ps2.mem_pos_regs[4] = 0xf2;
break;
case 8:
ps2.mem_pos_regs[4] = 0xfa;
break;
case 9:
ps2.mem_pos_regs[4] = 0xca;
break;
case 10:
ps2.mem_pos_regs[4] = 0xea;
break;
case 11:
ps2.mem_pos_regs[4] = 0x2a;
break;
case 12:
ps2.mem_pos_regs[4] = 0xaa;
break;
}
mca_add(ps2_mem_expansion_read, ps2_mem_expansion_write, NULL);
mem_mapping_add(&ps2.expansion_mapping,
0x400000,
(mem_size - 4096)*1024,
mem_read_ram,
mem_read_ramw,
mem_read_raml,
mem_write_ram,
mem_write_ramw,
mem_write_raml,
&ram[0x400000],
MEM_MAPPING_INTERNAL,
NULL);
mem_mapping_disable(&ps2.expansion_mapping);
}
}