Is this a PCI card? The base address might be at a different place then.

It's integrated, but I believe it runs off the PCI bus.
I'll check.

00:08.0 Multimedia audio controller: ESS Technology ES1969 Solo-1 Audiodrive (rev 02) Subsystem: ESS Technology Device 8 […]
Show full quote

00:08.0 Multimedia audio controller: ESS Technology ES1969 Solo-1 Audiodrive (rev 02)
Subsystem: ESS Technology Device 8898
Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 32 (500ns min, 6000ns max)
Interrupt: pin A routed to IRQ 5
Region 0: I/O ports at 7000
Region 1: I/O ports at 7080
Region 2: I/O ports at 70c0
Region 3: I/O ports at 7400
Region 4: I/O ports at 7440
Capabilities: [c0] Power Management version 1
Flags: PMEClk- DSI+ D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
Kernel driver in use: ESS ES1938 (Solo-1)
Kernel modules: snd-es1938

Well, there's the problem - and another one as well.
ioperm() Can only allow up to 0x3FF, so either iopl() or a kernel module is required.

Any thoughts?

Maybe there are driver switches to enable the legacy ports?

Interesting stuff, I haven't really done any linux programming but it doesn't look to be a simple job.
I'm going to try a few things and see if I can talk to the OPL hardware outside of dosbox using /dev/port.

[Edit]
May not be possible this way either.
🙁

Oddly enough using a YMF-724 ioperm() works because you can map the fm port to 0x388. However, /dev/port does not.
Meanwhile, in the ES1938 audio module:

1        /* disable legacy audio */
2        pci_write_config_word(chip->pci, SL_PCI_LEGACYCONTROL, 0x805f);

It may be there for a reason though.

Maybe some of you can give this quick hack a try:

1#include <sys/types.h>
2#include <sys/stat.h>
3#include <sys/io.h>
4#include <fcntl.h>
5#include <errno.h>
6#include <stdio.h>
7#include <string.h>
8
9#ifdef USE_DEVPORT
10static int Portfd = -1;
11#endif
12
13void alWrite( int Port, int Register, unsigned char Value ) {
14#ifndef USE_DEVPORT
15	outb( Register, Port );
16	usleep( 4 );
17	outb( Value, Port + 1 );
18	usleep( 24 );
19#else
20	if ( Portfd != -1 ) {
21		lseek( Portfd, Port, SEEK_SET );
22		write( Portfd, &Register, 1 );
23		usleep( 4 );
24
25		lseek( Portfd, Port + 1, SEEK_SET );
26		write( Portfd, &Value, 1 );
27		usleep( 24 );
28	}
29#endif
30}
31
32unsigned char alRead( int Port ) {
33	unsigned char Value = 0;
34
35#ifndef USE_DEVPORT
36	Value = inb( Port );
37	usleep( 4 );
38#else
39	if ( Portfd != -1 ) {
40		lseek( Portfd, Port, SEEK_SET );
41		read( Portfd, &Value, 1 );
42		usleep( 4 );
43	}
44#endif
45
46	return Value;
47}
48
49int DetectAdlib( int Port ) {
50	unsigned char R1, R2;
51
52	alWrite( Port, 0x04, 0x60 );	// Reset both timers
53	alWrite( Port, 0x04, 0x80 );	// Enable interrupts
54	R1 = alRead( Port );		// Read status register
55
56	alWrite( Port, 0x02, 0xFF );	// Timer 1
57	alWrite( Port, 0x04, 0x21 );	// Start timer 1
58	usleep( 80 );			// Delay for 80us
59
60	R2 = alRead( Port );		// Read status register

61	alWrite( Port, 0x04, 0x60 );
62	alWrite( Port, 0x04, 0x80 );
63
64	printf( "%X %X\n", R1, R2 );
65
66	R1&= 0xE0;
67	R2&= 0xE0;
68
69	return ( R1 == 0x00 && R2 == 0xC0 ) ? 1 : 0;
70}
71
72int main( int Argc, char** Argv ) {
73	int Port = 0;
74
75	if ( Argc < 2 ) {
76		printf( "usage: adlib [port hex]\n" );
77		return 1;
78	}
79
80	sscanf( Argv[ 1 ], "%x", &Port );
81
82	if ( Port < 0 ) {
83		printf( "Invalid port 0x%X\n", Port );
84		return 1;
85	}
86
87#ifndef USE_DEVPORT
88	if ( ioperm( Port, 2, 1 ) == 0 ) {
89		printf( "Got io permissions...\n" );
90
91		if ( DetectAdlib( Port ) == 0 ) {
92			printf( "No adlib at 0x%X\n", Port );
93		} else {
94			printf( "Found adlib at 0x%X\n", Port );
95		}
96	}
97#else
98	Portfd = open( "/dev/port", O_RDWR );
99
100	if ( Portfd > 0 ) {
101		printf( "Opened /dev/port...\n" );
102
103		if ( DetectAdlib( Port ) == 0 ) {
104			printf( "No adlib at 0x%X\n", Port );
105		} else {
106			printf( "Found adlib at 0x%X\n", Port );
107		}
108
109		close( Portfd );
110	} else {
111		printf( "Failed to open /dev/port.\n" );
112	}
113#endif
114
115	return 0;
116}

Compile with either -O2 for ioperm mode or -DUSE_DEVPORT for using /dev/port.
Note that this is a quick hack and only tests for one chip, at least here both methods detect at 0x388.

Edit:
This is really, really hacky.
Though maybe /dev/port can allow using the OPL hardware that uses ports beyond what ioperm can give.

Success!
On my laptop the ESFM is located at 0x7080h!

Does the passthrough also handle the SB completely in hardware?
Maybe we need a separate option to only pass through the OPL chip.

The SB hardware is not touched as interrupt and DMA passthrough are a different level of complexity.

Hello people,

I'm trying to accomplish this too. I can't find a DOSBox build that supports hardware OPL under GNU/Linux nor I don't know how to apply any of what is described in this thread.

How could I apply the hack by TheLazy1 to the source code and what should I change?

Thank you in advance.

This is my hardware:

1# lspci -vvv
2
3	04:01.0 Multimedia audio controller: C-Media Electronics Inc CMI8738/CMI8768 PCI Audio (rev 10)
4	Subsystem: C-Media Electronics Inc CMI8738/C3DX PCI Audio Device
5	Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping+ SERR- FastB2B- DisINTx-
6	Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
7	Latency: 32 (500ns min, 6000ns max)
8	Interrupt: pin A routed to IRQ 19
9	Region 0: I/O ports at e000 [size=256]
10	Capabilities: [c0] Power Management version 2
11		Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-)
12		Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
13	Kernel driver in use: snd_cmipci
14	Kernel modules: snd_cmipci
15

1$ cat /proc/asound/hwdep
202-00: OPL3 FM

1$ pmidi -l
2 Port     Client name                       Port name
3 24:0     C-Media CMI8738                   C-Media CMI8738 MIDI
4 25:0     OPL3 FM synth                     OPL3 FM Port

I can set up and the FM synth correctly with:

1$ sbiload -D /dev/snd/hwC2D0 --opl3 std.o3 drums.o3

PS: I don't know if this is the right procedure or if I should create a new thread.

Pretty please.

I already managed to compile the megabuild6 in Ubuntu 16.04 amd64.

I also had to use root to run it, otherwise I got:
OPL passthrough: permission denied. Aborting.

Tried different configs to no avail.

My ports are

1snd_cmipci: mpu_port=0x330 fm_port=0x388

Any help would be appreciated!

This is called necroposting, create a new thread please.