Re: Emulated PCI devices?
22.10.2016 16:34, Mouse пишет: Its just that usually when you have some expensive HW, emulating it in software is not enough because the HW is usually doing something useful, not just makes some program to work. :) If you don't need any functionality of that HW other than to make some DOS prog happy, Sort of. It's a (relatively-)high-speed input device, and we plan to replace it with either a pre-canned data file or a network connection as a data source. But, even once the host machine has the data, we have to get it into the program somehow. I could replace all the relevant hardware accesses with traps to the emulator, but I could also simulate the hardware it's expecting. I wonder if there is a big difference. Any hardware access you don't have ioperm permissions to, makes it into an emulator trap. So I very much suspect you are talking differently about the same thing. If you patch every in/out insn of your prog into hlt, nothing will really change other than it will be more difficult to simulate. then I am afraid dosemu is not prepared for that, and you'll need to implement the PCI emulator (in which case you can try qemu). OK, I'll talk with the other people invovled and we'll decide what tack to take: hack on the program, add PCI emulation to dosemu, switch emulators, whatever. Since dosemu is really a virtual machine (not like ntvdm or wine, for example dosemu can run real windows31), and so is qemu, you can get most of everything you had with dosemu, with qemu too. Its just that dosemu sets up many things for you automatically, which makes people think of it as of wine or ntvdm, but its not. With qemu you'll have to do a lot of manual setup to get the host FS access for example, but at the end you can get the same results. OTOH adding the PCI emulator to dosemu is not exceptionally difficult, provided that it already has the PCI bios and emulation of the config space ports. Its not like implementing everything from scratches because you likely only need to emulate the device config space. I suppose the device emulation itself will take much more time anyway, esp if it uses DMA. -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Emulated PCI devices?
> Its just that usually when you have some expensive HW, emulating it > in software is not enough because the HW is usually doing something > useful, not just makes some program to work. :) If you don't need > any functionality of that HW other than to make some DOS prog happy, Sort of. It's a (relatively-)high-speed input device, and we plan to replace it with either a pre-canned data file or a network connection as a data source. But, even once the host machine has the data, we have to get it into the program somehow. I could replace all the relevant hardware accesses with traps to the emulator, but I could also simulate the hardware it's expecting. I thought the latter was at least worth looking at; it would have the benefit that it would be running an identical software image to a real machine with real hardware, making some kinds of debugging and verification easier. > then I am afraid dosemu is not prepared for that, and you'll need to > implement the PCI emulator (in which case you can try qemu). OK, I'll talk with the other people invovled and we'll decide what tack to take: hack on the program, add PCI emulation to dosemu, switch emulators, whatever. Many thanks for all your help. Even if we end up switching away from it, dosemu has been extremely helpful in this endeavour! /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTMLmo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Emulated PCI devices?
>> [...] the way dosemu emulates DOS in much the same sense that wine >> emulates Windows, instead of emulating hardware proper [...] > dosemu does emulate the HW and uses freedos (or any other dos you ask > it to boot). To a point, sure. But, for example, it takes file I/O traps and provides its own implementation, backed by the host filesystem, rather than letting the FreeDOS implementation talk to (presumably emulated) disk hardware. >> [...] it involves a legacy application, running under DOS, which >> depends on a particular (relatively rare and expensive) piece of >> hardware. > If you want the DOS driver to communicate to that hardware, [...]. > If you want to emulate the "very expensive hw" without actually using > the real hw, then I wonder what's the point. The point is to get the application running without the fancy hardware (which is now EOLed) without having to rewrite the portions of the application that talk to it. The company has done an EOL buy of that hardware, but that gives them only enough to last about half the time we expect it to take to do the complete port/rewrite. /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTMLmo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Emulated PCI devices?
19.10.2016 03:03, Mouse пишет: I'm working with dosemu and would like to add an emulated PCI device to the emulated DOS machine. [...] Is this something that's already got hooks supporting it, or am I breaking new ground here? There was never any need to emulate the PCI device for DOS. There are hardly too many DOS drivers for the PCI devices. In general, perhaps not. :-) Maybe you can instead emulate the ISA version of that device, As far as I know, no ISA version has ever existed - and, indeed, the particular device in question has just recently been EOLed by its maker. Or maybe you simply want to use qemu It may come to that; I'm working with dosemu because that was the first DOS emulator we tried that we could make the software run in. And, in some respects, I prefer the way dosemu emulates DOS in much the same sense that wine emulates Windows, instead of emulating hardware proper dosemu does emulate the HW and uses freedos (or any other dos you ask it to boot). You can look into dosbox that "emulates" dos. and not caring what software is running on it. because I can't think of the real use-cases where you want to emulate some modern device under dosemu or dosbox. Well, I daresay they are not common, but I've got one. :-) I can't go into too much detail (NDAs and such), but it involves a legacy application, running under DOS, which depends on a particular (relatively rare and expensive) piece of hardware. If you want the DOS driver to communicate to that hardware, then dosemu is fully prepared to that, because no emulation is needed then. If you want to emulate the "very expensive hw" without actually using the real hw, then I wonder what's the point. -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Emulated PCI devices?
19.10.2016 00:45, Mouse пишет: I'm working with dosemu and would like to add an emulated PCI device to the emulated DOS machine. Obviously, I know enough about the hardware I want to emulate to believe I can write an emulation of it. But I'm not sure where to hook it in. (I'm working based on commit 18f6f5cdf1beceae8c7532718bfaf423e4a44f6a.) Good luck. I found src/base/async/pci_bios.c and src/base/dev/misc/pci.c, but they appear to be all about giving the emulated machine access to real PCI hardware on the real machine. That's not what I want; I'm trying to supply the emulated machine with hardware that is not actually present. There is src/env/video/matrox.c, which appears to be monkeying with PCI stuff, but even that checks the real machine's /proc/pci and doesn't run unless there's real hardware backing it (see matroxProbe(), which incidentally is incorrectly commented as being MGAProbe). Is this something that's already got hooks supporting it, or am I breaking new ground here? There was never any need to emulate the PCI device for DOS. There are hardly too many DOS drivers for the PCI devices. Maybe you can instead emulate the ISA version of that device, which should be much simpler than adding the PCI bus emulator. Or maybe you simply want to use qemu because I can't think of the real use-cases where you want to emulate some modern device under dosemu or dosbox. -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Emulated PCI devices?
I'm working with dosemu and would like to add an emulated PCI device to the emulated DOS machine. Obviously, I know enough about the hardware I want to emulate to believe I can write an emulation of it. But I'm not sure where to hook it in. (I'm working based on commit 18f6f5cdf1beceae8c7532718bfaf423e4a44f6a.) I found src/base/async/pci_bios.c and src/base/dev/misc/pci.c, but they appear to be all about giving the emulated machine access to real PCI hardware on the real machine. That's not what I want; I'm trying to supply the emulated machine with hardware that is not actually present. There is src/env/video/matrox.c, which appears to be monkeying with PCI stuff, but even that checks the real machine's /proc/pci and doesn't run unless there's real hardware backing it (see matroxProbe(), which incidentally is incorrectly commented as being MGAProbe). Is this something that's already got hooks supporting it, or am I breaking new ground here? /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTMLmo...@rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B -- To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
