Add a pretty bare bones implementation of APM 1.1 that can turn on and off the power supply and grahics card. This implementation would also query battery life but I don't have anything to test it on.

Author: joshudson

8086tiny.c

@@ -65,6 +65,7 @@
 #ifndef GRAPHICS_UPDATE_DELAY
 #define GRAPHICS_UPDATE_DELAY 360000
 #endif
+#define APM_INST_DELAY 1000
 #define KEYBOARD_TIMER_UPDATE_DELAY 20000
 #define HALT_TIME_MICROSECONDS 100
 #define KEYBOARD_TIMER_DELAY_FROM_HALT 1000
@@ -205,11 +206,14 @@ unsigned char mem[RAM_SIZE + 16], io_ports[IO_PORT_COUNT + 16],
 	hlt_this_time, setting_ss, prior_setting_ss, reset_ip_after_rep_trace,
 	shift_count;
 unsigned short *regs16, reg_ip, seg_override, file_index, wave_counter, reg_ip_before_rep_trace;
-unsigned int op_source, op_dest, rm_addr, op_to_addr, op_from_addr, i_data0, i_data1, i_data2, scratch_uint, scratch2_uint, keyboard_timer_inst_counter, graphics_inst_counter, set_flags_type, GRAPHICS_X, GRAPHICS_Y, pixel_colors[16], vmem_ctr;
-int op_result, disk[3], scratch_int;
+unsigned int op_source, op_dest, rm_addr, op_to_addr, op_from_addr, i_data0, i_data1, i_data2, scratch_uint, scratch2_uint, keyboard_timer_inst_counter, graphics_inst_counter, apm_inst_counter, set_flags_type, GRAPHICS_X, GRAPHICS_Y, pixel_colors[16], vmem_ctr;
+int op_result, disk[3], scratch_int, device_status;
 time_t clock_buf;
 struct timeb ms_clock;
 
+#define DEVICE_STATUS_GRAPHICS 1
+#define DEVICE_STATUS_FASTCPU 2
+
 #ifndef NO_GRAPHICS
 SDL_AudioSpec sdl_audio = {44100, AUDIO_U8, 1, 0, 128};
 SDL_Surface *sdl_screen;
@@ -220,6 +224,7 @@ unsigned short vid_addr_lookup[VIDEO_RAM_SIZE], cga_colors[4] = {0 /* Black */,
 // Helper functions
 
 void callxms();
+void callapm();
 
 // Set carry flag
 char set_CF(int new_CF)
@@ -848,6 +853,8 @@ int main(int argc, char **argv)
 							: (errno == EINVAL) ? 0x04 /* out of range on disk device */ : 0xAA /* no disk */;
 					OPCODE 4:	// XMS
 						callxms();
+					OPCODE 5:
+						callapm();
 				}
 				if ((uint8_t)i_data0 == 11	// ud2
 					|| (uint8_t)i_data0 >= 32)
@@ -1023,7 +1030,7 @@ int main(int argc, char **argv)
 			graphics_inst_counter = 0;
 			hlt_this_time = 0;
 			// Video card in graphics mode?
-			if (io_ports[0x3B8] & 2)
+			if (io_ports[0x3B8] & 2 && device_status & DEVICE_STATUS_GRAPHICS)
 			{
 				// If we don't already have an SDL window open, set it up and compute color and video memory translation tables
 				if (!sdl_screen)
@@ -1057,6 +1064,11 @@ int main(int argc, char **argv)
 			SDL_PumpEvents();
 		}
 #endif
+		if (!setting_ss && !hlt_this_time && !(device_status & DEVICE_STATUS_FASTCPU) && ++apm_inst_counter >= APM_INST_DELAY) {
+			hlt_this_time = 1;
+			apm_inst_counter = 0;
+		}
+
 		if (hlt_this_time) {
 			struct timespec ts;
 			ts.tv_sec = 0;
@@ -1240,6 +1252,54 @@ uint32_t getfreexms() {
 	return lower;
 }
 
+void callapm() {
+	char buf[12];
+	int h, tmp;
+	switch (regs8[REG_AH]) {
+	OPCODE_CHAIN 0: // CPU slow
+		device_status &= ~DEVICE_STATUS_FASTCPU;
+	OPCODE 1: // CPU normal
+		device_status |= ~DEVICE_STATUS_FASTCPU;
+	OPCODE 2: // graphics card off
+		device_status &= ~DEVICE_STATUS_GRAPHICS;
+	OPCODE 3: // graphics card on
+		device_status |= DEVICE_STATUS_GRAPHICS;
+	OPCODE 4: // Get battery status
+#ifdef _WIN32
+		regs8[REG_BL] = 0xff;
+#else
+		h = open("/sys/class/power_supply/BAT0/status", O_RDONLY);
+		if (h >= 0 && (0 < read(h, buf, 12)))
+			regs8[REG_BL] = buf[0] == 'C' ? 3 /* charging */ : 2 /* critical */;
+		else
+			regs8[REG_BL] = 0xFF; // Unable
+		if (h >= 0) close(h);
+		h = open("/sys/class/power_supply/BAT0/capacity", O_RDONLY);
+		if (h >= 0 && ((tmp = read(h, buf, 10)) > 0))
+			buf[tmp] = 0, regs8[REG_CL] = atoi(buf);
+		else
+			regs8[REG_CL] = 0xFF; // Unable
+		if (h >= 0) close(h);
+		if (regs8[REG_CL] != 0xFF && regs8[REG_BL] == 2) {
+			if (regs8[REG_CL] >= 50) regs8[REG_BL] = 0; // High
+			else if (regs8[REG_CL] >= 10) regs8[REG_BL] = 1; // Low
+			// If we can't get battery charge and we're not charging it's critical
+		}
+#endif
+	OPCODE 5: // Get AC status
+#ifdef _WIN32
+		regs8[REG_BH] = 0xff;
+#else
+		h = open("/sys/class/power_supply/AC/online", O_RDONLY);
+		if (h >= 0 && (0 < read(h, buf, 2)))
+			regs8[REG_BH] = buf[0] - 1; // 0 = offline, 1 = online
+		else
+			regs8[REG_BH] = 0xFF; // Unable
+		if (h >= 0) close(h);
+#endif
+	}
+}
+
 
 void callxms() {
   uint32_t ii, free;

bios.asm

@@ -88,7 +88,15 @@ bios_entry:
 
 	; Now we can do whatever we want! DL starts off being the boot disk.
 
+	cmp	byte [cs:boot_state], 0
+	jne	.warm_early_boot
 	mov	[cs:boot_device], dl
+.warm_early_boot:
+	mov	[cs:apm_flags], byte 0
+
+	; Set CPU to high power
+	mov	ah, 1
+	db	0x0f, 0x05
 
 	; Set up Hercules graphics support. We start with the adapter in text mode
 
@@ -111,6 +119,10 @@ bios_entry:
 	mov	al, 0x57	; 0x57 = 87 (* 4) = 348 pixels high (GRAPHICS_Y)
 	out	dx, al
 
+	; Graphics power on
+	mov	ah, 3
+	db	0x0f, 0x05
+
 	pop	dx
 
 	pop	ax
@@ -2610,6 +2622,8 @@ int15:	; Here we do not support any of the functions, and just return
 	; je	int15_intercept
 	cmp	ah, 0x88
 	je	int15_getextmem
+	cmp	ah, 0x53
+	je	int15_apm
 
 ; Otherwise, function not supported
 
@@ -2643,10 +2657,218 @@ int15_getextmem:
 	db 0Fh, 04h		; call into XMS interface
 	cmc			; if it returned NC, it means error
 	jnc .ret		; no error -->
-	mov ah, 86h
+	; No XMS interface but high memory exists
+	mov ax, 64
+	clc
 .ret:
 	jmp reach_stack_carry
 
+int15_apmversion:
+	cmp	cx, 0x101
+	ja	.nope
+	mov	ax, 0x101
+	jmp	reach_stack_clc
+.nope	mov	ah, 0x0b
+	jmp	reach_stack_stc
+
+int15_apmbogonstate:
+	jmp	reach_stack_clc
+
+int15_apm:
+	cmp	al, 0
+	je	.apmchk
+	cmp	al, 1
+	je	.real
+	cmp	al, 2
+	je	.prot16
+	cmp	al, 3
+	je	.prot32
+	cmp	al, 4
+	je	.realdc
+	cmp	al, 5
+	je	.cpuidle
+	cmp	al, 6
+	je	.cpubusy
+	cmp	al, 7
+	je	.setpower
+	cmp	al, 8
+	je	.ends
+	cmp	al, 9
+	je	.ends
+	cmp	al, 10
+	je	.getbattery
+	cmp	al, 11
+	je	.getevent
+	cmp	al, 12
+	je	.getpower
+	cmp	al, 13
+	je	int15_apmbogonstate
+	cmp	al, 14
+	je	int15_apmversion
+	mov	ah, 0ah
+	jmp	.fail
+
+.prot16:	; 16 bit protected mode, but we're an 8086
+	mov	ah, 6
+	jmp	.fail
+.prot32:	; 32 bit protected mode, lolno
+	mov	ah, 8
+.fail	jmp	reach_stack_stc
+.apmchk:
+	mov	ax, 0x101
+	mov	bx, 'PM'
+	mov	cx, 4
+.ok	jmp	reach_stack_clc
+
+.realdc:	; Real mode APM disconnect
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	mov	[cs:apm_flags], byte 0
+	mov	ah, 1			; Take CPU out of idle
+	db	0x0f, 0x05
+	jmp	reach_stack_clc
+.notconnected:
+	mov	ah, 0x03
+	jmp	.fail
+
+.real:	; Real mode connect -- neither of these do anything interesting
+	; Suspend would turn off the mouse; so we can't easily implement a good idle policy
+	test	[cs:apm_flags], byte 1
+	jnz	.realalready
+	or	bx, bx
+	jnz	.fail
+	mov	[cs:apm_flags], byte 1
+	jmp	.ok
+.realalready:
+	mov	ah, 0x02
+	jmp	.fail
+
+.cpuidle:
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	push	ax
+	mov	ah, 0
+	db	0x0f, 0x05
+	pop	ax
+	jmp	.ok
+
+.cpubusy:	; Documentation says bios should be able to tell; this bios can't
+		; However this bios can only slow on cpuidle so it's all right
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	push	ax
+	mov	ah, 1
+	db	0x0f, 0x05
+	pop	ax
+	jmp	.ok
+
+.ends:		; Enable/disable is NOP
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	cmp	bx, 0xffff
+	je	.ok
+	jmp	.fail
+
+.setpower:
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	cmp	cx, 3
+	ja	.nos
+	je	.cxk
+	cmp	cx, 0
+	jne	.nxs
+.cxk	cmp	bx, 1
+	je	.system
+	cmp	bx, 0x100
+	je	.graphics
+.nodevice:
+	mov	ah, 9
+	jmp	.fail
+.nos	mov	ah, 0x0a
+	jmp	.fail
+.nxs	mov	ah, 0x60
+	jmp	.fail
+
+.system	cmp	cx, 3
+	je	.poweroff
+	jmp	.ok
+.graphics:
+	push	ax
+	mov	ah, 3
+	cmp	cx, 3
+	and	[cs:apm_flags], byte 0xfb
+	je	.graphicsoff
+	mov	ah, 2
+	or	[cs:apm_flags], byte 4
+.graphicsoff:
+	db	0x0f, 0x05
+	pop	ax
+	jmp	.ok
+
+.poweroff:	; Turn off the system
+	mov	bx, bp	; Get error code from caller, if any
+	mov	ax, dx
+	jmp	0:0
+
+.getpower:
+	cmp	bx, 0x100
+	je	.getgraphics
+	cmp	bx, 1		; System
+	jne	.nodevice
+	mov	cx, 1
+	jmp	.ok
+.getgraphics:
+	xor	cx, cx
+	test	[cs:apm_flags], byte 4
+	jz	.getgraphicson
+	mov	cl, 3
+.getgraphicson:
+	jmp	.ok
+
+.getbattery:
+	cmp	bx, 1
+	ja	.nodevice	; asks for specific battery; but we are APM 1.1
+	push	ax
+	; This call always succeeds
+	mov	ah, 4
+	db	0x0f, 0x05
+	mov	ah, 5
+	db	0x0f, 0x05
+	pop	ax
+	jmp	reach_stack_clc
+
+.getevent:
+	; There's only one event: battery
+	test	[cs:apm_flags], byte 1
+	jz	.notconnected
+	push	bp
+	mov	bp, sp
+	push	ax
+	push	bx
+	push	cx
+	mov	ah, 4
+	db	0x0f, 0x05
+	cmp	bl, 2
+	jne	.gennocrit
+	test	[cs:apm_flags], byte 2
+	jz	.gencritalready
+	or	[cs:apm_flags], byte 2
+	; I hate this specification. What is labelled as low battery notification is critical battery notification and
+	; what is labelled as critical battery notification is critical batter after waking from unscheduled suspend. -JH
+	mov	[bp - 4], word 5	; AX = battery notification
+	clc
+	jmp	.geexit
+.gennocrit:
+	and	[cs:apm_flags], byte 0xfd
+.gencritalready:
+	mov	[bp - 1], byte 80h	; AH = no event
+	stc
+.geexit:
+	pop	cx
+	pop	bx
+	pop	ax
+	pop	bp
+	jmp	reach_stack_carry
 
 ; ************************* INT 16h handler - keyboard
 
@@ -4050,6 +4272,9 @@ crt_curpos_y_last	db	0
 last_int8_msec	dw	0
 last_key_sdl	db 	0
 
+; APM data
+apm_flags	db	0
+
 ; Now follow the tables for instruction decode helping
 
 		align 8