What does Linux have against ASUS (or vice versa)?

Erik_FL · 03-25-2007, 01:03 PM

I'm very confused about this whole business of how Linux allocates the device names and recognizes the controllers for mixed SATA / PATA controllers.

The configuration that causes the least problems is this.

Put all PATA drives on the ICH5 controller.
Put all SATA drives on the Promise controller.
Set the ICH5 to be in "P-ATA Ports Only" mode.

That will put all the ICH5 devices on "hd" devices and all Proimse drives on "sd" devices.
It also avoids putting PATA drives on the Promise controller. That isn't supported by the "standard" Linux driver. Your distro apparently has PATA support in "sata_promise" but you can't depend on that being present in the future.

If you mix SATA and PATA drives on the Promise controller be prepared for these possible problems. Adding a SATA drive may change the device name of the PATA drive or the BIOS designation (for example 0x80 to 0x81). I have never tried to boot from a PATA drive on the Promise controller when SATA drives are also connected. I don't know if that configuration will work.

If you mix SATA and PATA drives on the ICH5 you may have these problems.
In "Legacy" mode the SATA drives will appear as "hd" not "sd" devices and will operate at slower ATA-100 speeds. In "Enhanced" mode the SATA drives will appear as "sd" devices but may not be able to share the ICH5 with the IDE driver for the "hd" devices. With the ICH5 in "Enhanced" mode kernel version 2.6 will probably work better than version 2.4.

In your current hardware configuration I can think of some possible explanations for the problems.

When you connect a SATA drive to the Promise controller, either the device name or the BIOS drive ID (0x80) for the PATA boot drive is changing. Linux boots, but is unable to mount the root device. If you're going to boot from a PATA disk it should be connected as the Primary IDE Master on the ICH5. Otherwise you will have to keep changing the boot configuration depending on the location of other drives.

When you connect a SATA drive to the ICH5 you may be expecting to see it show up as a "sd" device, but that isn't necessarily what will happen. In "Legacy" mode the SATA drives appear to be "hd" devices and operate in the slower ATA-100 transfer mode. This may be the only way to use SATA drives in kernel version 2.4. I think you might also have to include some "older IDE driver SATA support" option in the kernel build.

If you use "Enhanced" mode for the ICH5 then the SATA drives will show up as "sd" devices. That will probably only work with kernel version 2.6 since the "sd" and "hd" drivers have to share the interrupt for the ICH5 controllers. It may also change the device name of your boot drive on the Promise controller.

Don't even try to use RAID mode for the Promise controller, because you need additional drivers or software to make that work. I have that working with Linux but it is complicated.

When you make hardware changes I recommend that you boot the Linux installation CD, and then look at the device name assignments to determine which hard disks are where. You can use "cfdisk" to find out the partitions on each drive. The interaction between the different drivers for the Promise and ICH5 is complicated and it's difficult to accurately predict the effect of making a change.

I also recommend using GRUB rather than LILO. It's much easier to reconfigure the GRUB boot configuration (editing "menu.lst"). Changing the LILO configuration requires rewriting the boot block from Linux. Also, GRUB can be installed from a boot floppy or CD in "Native" mode using the BIOS. You can use that mode of GRUB to check the actual device locations as seen by the BIOS. Changing the "boot device" in the BIOS will probably change the BIOS IDs so you should avoid doing that.

xp_newbie · 03-26-2007, 08:13 AM

Erik, I agree with most of what you wrote here. I especially believe that the configuration that causes the least problems is when:

All PATA drives are on the ICH5 controller,
All SATA drives are on the Promise controller and
Ahe ICH5 is set to "P-ATA Ports Only" mode.

At the moment, I can summarize the current situation as follows:

Putting the PATA HDD on the Promise controller was intentional from the beginning, since it allows me to squeeze in a little extra bandwidth: UDMA6 (133 MB/s) on the Promise (PATA) vs. UDMA5 (100 MB/s) on the ICH5 (PATA). Thus, I am not interested in switching the PATA HDD to the ICH5 controller.
Even if I switch the PATA HDD to the ICH5, I believe that Linux (at least this Ubuntu distro) will require re-intallation. Linux is simply not as good as Windows in adapting to hardware configuration changes. Now that I understood this point, I can devise some workaround. If I have to reinstall the OS, I'd rather do it on the 400GB SATA HDD connected to the Promise controller, since this will allow me to use it at UDMA7 (150 MB/s).
I have no intention to mix PATA and SATA on the ICH5. I do intend to mix PATA and SATA on the Promise, but if that is not possible, I will move the PATA HDD to the ICH5 as it will no longer be my main working HDD (i.e. the one with the OS and VMWare VMs).
I have been using RAID mode for the Promise controller from day one - without any problem (on the current Linux installation). That is, as long as I don't introduce any hardware configuration changes. I didn't have to do any special or complicated customization - I just used Ubuntu 6.06 as is out-of-the box.
I have also been using GRUB from day one.

I suspect that upon fresh installation, Linux will deal well with the PATA and SATA drives both on the Promise controller. I will report back the results of this experiment, once I have the time (it may take several weeks, though).

Thanks,
Alex

Erik_FL · 03-26-2007, 12:36 PM

I should have been clearer about what I meant by RAID. I was referring to the hardware RAID mode of the Promise controller, with RAID enabled in the BIOS. That requires either the "dmraid" program (kernel v2.6) or the RAID driver from the Promise site (kerenel v2.4).
The OS RAID on Linux works fine with the "sata_promise" driver, using it as a "normal" Linux block device.

I know that Linux supports PATA ports on the Promise controller because I'm using that configuration. If you want to get UDMA6 (133 MB/s) on the Promise (PATA) you should be aware that not all versions of the "sata_proimse" driver operate the PATA port in that mode.
Some versions of the driver ("sata_promise.c") have this code.

Code:

static void pdc_pata_phy_reset(struct ata_port *ap)
{
	/* FIXME: add cable detect.  Don't assume 40-pin cable */
	ap->cbl = ATA_CBL_PATA40;
	ap->udma_mask &= ATA_UDMA_MASK_40C;

	pdc_reset_port(ap);
	ata_port_probe(ap);
	ata_bus_reset(ap);
}

The code that supports high speed DMA should look similar to this.

Code:

static void pdc_pata_phy_reset(struct ata_port *ap)
{
	u8 tmp;
	void *mmio = (void *) ap->ioaddr.cmd_addr + PDC_CTLSTAT + 0x03;

	tmp = readb(mmio);
	
	if (tmp & 0x01) {
		ap->cbl = ATA_CBL_PATA40;
		ap->udma_mask &= ATA_UDMA_MASK_40C;
	} else {
		ap->cbl = ATA_CBL_PATA80;
	}

	pdc_reset_port(ap);
	ata_port_probe(ap);
	ata_bus_reset(ap);
}

It's pretty obvious that you have the version of "sata_promise" with PATA support, since the other version won't detect the PATA drives. The DMA mode changes are not so obvious without inspecting the code.

In theory, it should be possible to modify Linux to boot without having to re-install it. Finding out the required changes may take more time than reinstalling Linux.

I think that installing Linux on an SATA drive is a good idea. That will mean that the boot disk will always have an "sd" device name and use the newer SATA drivers. Booting from a PATA disk creates problems because the device driver depends on where it's connected. Also, the first SATA port on the Promise controller always seems to be the first "sd" device for the controller. You should be able to connect or disconnect other drives PATA/SATA to the Promise controller without the boot device name changing. As long as you don't enable SATA support on the ICH5 there should be no change in the first "sd" device assigned to the Promise controller.

I don't know the affect of adding or removing drives on the BIOS drive IDs (0x80, 0x81 ...). On my P4C800-E BIOS the drive ID depends on which disk controller I select as the "first" controller (ICH5 versus Promise). That BIOS option isn't mentioned in my BIOS manual (or yours) but it is present in the BIOS version that I have. I've seen some BIOS software that reassigns drive IDs based on which disk you actually boot. Windows only knows how to boot (NTLDR) and format a boot sector using BIOS drive ID 0x80. GRUB can be booted from any drive ID. In order for the BIOS to boot directly to GRUB, the partition or disk specified in the GRUB "setup" command must be on drive ID 0x80. If the rest of GRUB is not on the drive with ID 0x80 then both disks have to be connected in order to boot GRUB. The GRUB boot sector has to be rewritten if the location of GRUB or the drive ID for the GRUB files changes. I just installed both GRUB and NTLDR to the first hardware RAID array on the Promise controller so that they will use drive ID 0x80. I also set my BIOS to detect the Promise controller as the "first" disk controller.

Since I use hardware RAID, I either have to load the "ft3xx" driver from the Promise web site or use the "dmraid" utility with the "sata_promise" driver. Since some of my RAID drives are PATA I have to use the modified "sata_promise" driver that isn't "standard" in the Linux source or Slackware. Some distros like Ubuntu have modified versions of "sata_promise" but I can't say which have both PATA support and 80-pin cable high speed DMA support. I edited the changes in the driver that I'm using because I wanted to use Linux kernel version 2.6.17 with Slackware. I'm hoping that both of those changes will be a standard part of Linux in the near future.

The only advantages to using hardware RAID are that I can boot from the RAID array, and access all the partitions in the RAID array from any operating system (Windows, Linux, DOS, etc.).
Using OS RAID, only the operating system that creates a RAID partition can access that RAID partition. Depending on the boot support in the OS, it may or may not be possible to boot from an OS RAID partition.

xp_newbie · 03-27-2007, 09:25 AM

Quote:

Originally Posted by Erik_FL

I should have been clearer about what I meant by RAID. I was referring to the hardware RAID mode of the Promise controller, with RAID enabled in the BIOS.

That's exactly what I understood and that's exactly what I have been using - the "hardware" RAID mode of the Promise controller, with RAID enabled in the BIOS. I put the word "hardware" in quotation marks because I read somewhere that although this RAID is part of the motherboard, it is actually implemented in firmware. I don't know how true this is and whether there is any performance advantage to using the BIOS RAID vs. the one that comes with Linux.

As for the rest of what you wrote, all I can say for now is WOW! (you know so much about this subject - I wish I knew half of that).

I will report back when time comes for reinstallation.

Thanks,
Alex

Erik_FL · 03-27-2007, 11:21 AM

Quote:

Originally Posted by xp_newbie

That's exactly what I understood and that's exactly what I have been using - the "hardware" RAID mode of the Promise controller, with RAID enabled in the BIOS. I put the word "hardware" in quotation marks because I read somewhere that although this RAID is part of the motherboard, it is actually implemented in firmware. I don't know how true this is and whether there is any performance advantage to using the BIOS RAID vs. the one that comes with Linux.

As for the rest of what you wrote, all I can say for now is WOW! (you know so much about this subject - I wish I knew half of that).

I will report back when time comes for reinstallation.

Thanks,
Alex

From what I understand, if you connect only one drive to the Promise controller it isn't actually operating in "hardware" RAID mode. There are no RAID sets defined. Unless I'm missing something you said that you have just a PATA drive connected.

When you connect a second drive, then the Promise RAID BIOS will operate in RAID mode. Unless you actually plan to define RAID sets using the Promise BIOS you should set the IDE mode and not RAID mode for the Promise Controller.

The Promise controller and ICH5 are both "fake hardware RAID" controllers. They are ordinary disk controller hardware with RAID implemented in the BIOS firmware and a special OS driver. The BIOS firmware is used for booting, and for anything that makes BIOS calls to access hard disks. The OS driver makes the multiple disk controllers and disks appear to be one disk drive to the operating system. The OS driver also issues multiple I/O transfers to do the stiping or mirroring. Connecting more than two or three drives is probably a net loss in performance.

The Linux RAID driver for the Promise controller is called "ft3xx" and can be downloaded from the Promise web site. There is no RAID driver for the Promise controller that supports kernel version 2.6. You can use a program called "dmraid" to configure the device mapper in Linux to work through the "sata_promise" driver. Booting from a RAID set on the Promise controller is complicated. I am doing that but in retrospect I probably should have done something else.

The Windows RAID driver and SATA driver for the Promise controller are two different drivers. You have to install the correct driver (RAID versus SATA) depending on whether you have RAID enabled and RAID sets defined on the Promise controller. I'm not sure how intelligent the drivers are about checking that the correct driver is used for the correct mode of the controller.

With the Promise controller and the ICH5 there is no performance advantage to the simulated hardware RAID versus the Operating System RAID. There are really only two reasons to use the simulated hardware RAID. One is so that you can boot from the RAID array using the BIOS. The other is so that multiple operating systems can see the same RAID array and access the same partitions. Without the simulated hardware RAID each operating system can only see its own OS RAID partitions.

The downside of simulated hardware RAID is the problem of driver availability. The "dmraid" program and device mapper in Linux 2.6 have helped, since you can use the standard Linux drivers instead of proprietary drivers like "ft3xx". However, "dmraid" is not a standard part of Linux and the device naming behavior makes it difficult to boot from a RAID array using "dmraid".

To boot from the Promise RAID controller I had the following problems.

For Linux 2.4

There is no Slackware or Ubuntu "ft3xx" driver
I had to build "ft3xx" on some other computer
The "ft3xx" driver cannot be built into the kernel
I had to make an "initrd" image to load "ft3xx"

For Linux 2.6

The "ft3xx" driver does not support kernel version 2.6
The standard "sata_proimse" doesn't support PATA
I had to edit "sata_promise" to support PATA and high speed DMA
I had to obtain and use "dmraid"
The standard "initrd" doesn't work with "dmraid"
I had to write my own script to make an "initrd"
The standard init scripts don't work with "dmraid"
I had to edit the Linux init scripts
The "dmraid" device names depend on the RAID set name
I had to use device names like /dev/mapper/pdc_bbbffffihj3

KimVette · 03-27-2007, 11:46 AM

Quote:

Originally Posted by xp_newbie

So, I couldn't avoid the following question: ASUS is known as a high quality board manufacturer. Its performance when Windows is installed clearly demonstrates it. [B]So, how come Linux cannot (or does not want to) handle the apparent BIOS bugs (which Microsoft Windows have no problem dealing with)?

For what it's worth (and PLEASE do not take offense), that model board is crap. I built two Windows machines with those boards, and those machines were mistakes. We replaced the boards with other models.

Windows may work optimally on those boards from a casual user perspective but not for applications which require precise timing (i.e., multiple video concentrator cards, asterisk, etc) or performance.

Asus made MUCH better boards in the same price range.

linwing · 03-31-2007, 07:30 PM

I find this thread a little funny. Let's see i run over a dozen linux distros on several Asus mobos, one of them being the P4P800E Deluxe, with zero problems. In fact, once i install say PcLinuxOs, Mepis, Ubuntu, Xandros on a drive attached to one of these mobos, i can usually swap the drive to the others without doing any more than tweaking the nic settings which takes about a minute. And some of them simply pick up the new nic on the first boot.

It helps that i run a series of compatible but not identical nvidia video cards when i want to do this. Otherwise, installing linux only brings whatever difficulties typical of the distro, not something specific to an 'Asus' mobo.

This includes various linux distros on a variety of Ide drives, Sata drives, some quad booted, some booted on single drives, some drives new, some drives dating back as far as '95. No problems.

My other boards by Asus that do this for instance, are the P4C800E Deluxe, the P4P800SE. The P4C is based on the intel 875 and the other two are based on the intel 865PE chipsets which have given me zero difficulties running all kinds of linux distros. That includes a DFI Infinity and a Msi 865PE Neo2 LS.

They work fine in Windows also.

All of these boards are a dream with linux, including the Asus mobos. If you want headaches, that would be in the newer Intel 965's with the jmicron controller or even my Intel 945 with the typical one ide port, by design, such that i have to add an Ide Controller card for my hard drives if i want to run my Ide hard drives and my pair of optical drives. Such is the price of innovation and speed since they're oriented towards sata drives.

But the Asus boards i cited are great for linux (or Windows), give me a break. Such disinformation here about a brand and mobo model and i use all the brands as far as that goes.

And as far as that about Linux and Hardware, especially with regard to these particular mobos, generally i find Linux easier to install, and with some of the distros faster than installing Windows although neither is that hard.

Erik_FL · 04-01-2007, 09:45 AM

Quote:

Originally Posted by linwing

I find this thread a little funny. Let's see i run over a dozen linux distros on several Asus mobos, one of them being the P4P800E Deluxe, with zero problems. In fact, once i install say PcLinuxOs, Mepis, Ubuntu, Xandros on a drive attached to one of these mobos, i can usually swap the drive to the others without doing any more than tweaking the nic settings which takes about a minute. And some of them simply pick up the new nic on the first boot.

It helps that i run a series of compatible but not identical nvidia video cards when i want to do this. Otherwise, installing linux only brings whatever difficulties typical of the distro, not something specific to an 'Asus' mobo.

This includes various linux distros on a variety of Ide drives, Sata drives, some quad booted, some booted on single drives, some drives new, some drives dating back as far as '95. No problems.

My other boards by Asus that do this for instance, are the P4C800E Deluxe, the P4P800SE. The P4C is based on the intel 875 and the other two are based on the intel 865PE chipsets which have given me zero difficulties running all kinds of linux distros. That includes a DFI Infinity and a Msi 865PE Neo2 LS.

They work fine in Windows also.

All of these boards are a dream with linux, including the Asus mobos. If you want headaches, that would be in the newer Intel 965's with the jmicron controller or even my Intel 945 with the typical one ide port, by design, such that i have to add an Ide Controller card for my hard drives if i want to run my Ide hard drives and my pair of optical drives. Such is the price of innovation and speed since they're oriented towards sata drives.

But the Asus boards i cited are great for linux (or Windows), give me a break. Such disinformation here about a brand and mobo model and i use all the brands as far as that goes.

And as far as that about Linux and Hardware, especially with regard to these particular mobos, generally i find Linux easier to install, and with some of the distros faster than installing Windows although neither is that hard.

Linux works well if the hardware is supported by Linux. Unfortunately simulated hardware RAID "fake RAID" is not supported well by Linux. The main limitation with Linux is the lack of available drivers for some hardware. My P4C800E works well with Linux unless I try to use RAID on the Promise disk controller. I don't blame Linux for the lack of drivers, but it still limits the hardware where Linux can be used.

Linux also has problems sharing PCI interrupts between the old IDE drivers and the new SATA drivers implemented as SCSI devices. Personally I think Linux should treat ALL disk block devices the same way (either as SCSI devices or NOT). Changing a disk controller port from IDE to SATA, or SATA to IDE causes device names to shift (even among other disk drives).

When you run into one of the limitations of Linux you may not find it funny at all. I've spent literally days trying to solve compatibility problems with Linux and my P4C800E's Promise RAID controller. The standard "sata_promise" driver in Linux doesn't support many of the features of the controller.

It doesn't support the PATA (IDE) port
It doesn't support high speed DMA on the PATA port
It doesn't support the RAID operating mode

Promise has a driver for Linux 2.4 (not 2.6) but it also has lmitations.

It can only be built as module not as part of the kernel
Promise provides only partial source (it can't be modified)
ASUS does not make the Linux driver available for motherboards
You have to build the driver on some other computer BEFORE installing

The success or failure of Linux is going to depend largely on how well it can keep up with the accelerating changes in PC hardware. The days of the "standard" PC with a known set of hardware are nearly over.

One major problem with Linux distros is that they don't all support the same hardware, and they don't all load the same driver module binaries. Unless a hardware manufacturer provides a compatible module one can't easily install Linux on a disk that requires a proprietary device driver.

linwing · 04-01-2007, 11:21 AM

On page one of this thread there is this: "In my quest for an optimal run of Linux on the P4P800-E Deluxe motherboard, I tried to install Ubuntu 6.10, then Fedora Core 6, then Fedora Core 4, then Slackware 11... But none of them succeed passing the IRQ confusion in this motherboard." End quote. This followed where the thread author said Ubuntu 6.06LT install failed on this mobo.

And the rest on here about 'Asus and Linux," and the P4P800-E. Along with the 'buggy Asus bios,' the mobo is 'crap (at least that was qualified),' the 'what does Asus have against Linux and vice-versa.'

Since in the first place, as i indicated, this mobo and my other Asus mobos WILL install linux fine. I've done it on those (except on slackware i installed 10.2 instead of 11), and a lot more linux distros, and also with the rest of the mobos i cited. And it was easy, easier for me than installing Windows on most of them since usually when the install is complete, i didn't have to so much as touch anything and everything works. If i want Beryl, yes i may have to configure the video card. If some are in beta, there may be some known issues. None of which has anything in particular to do with 'Asus and Linux.'

If you want to get into a long discussion about linux and raid ok. I don't use raid and i don't need to use the Promise controller anyway, There are already two native ide ports and separate sata ports to use on the P4P800E Deluxe that work fine and of the mobos i cited, only the P4C and the P4PE Deluxe have the additional Promise controller anyway. That gives you without the Promise, 4 Ide drives plus Sata drives without ever touching the Promise which i don't. If you want to say you have problems installing linux using the Promise Raid controller, i believe that. If you want to say that sometimes we run into hardware/software hades in linux (or windows) and this is one of them, ok.

I referenced the JMicron controller as an instance of a newer device that seems to make what used to be easy in linux, running your ide hard drive and your cd/dvd burner, difficult. Yes it happens. Usually linux catches up with these.

At any rate running linux on the Asus P4P800E Deluxe is a piece of cake as it is for me with any of my intel 865PE/875 chipset based mobos like that, especially by now.

xp_newbie · 05-23-2007, 11:24 AM

Quote:

Originally Posted by xp_newbie

I suspect that upon fresh installation, Linux will deal well with the PATA and SATA drives both on the Promise controller. I will report back the results of this experiment, once I have the time (it may take several weeks, though).

YUP!

Just as I suspected in my previous post here, Ubuntu has no problem dealing with both the 400GB SATA HDD and the 160GB PATA HDD on the same Promise controller - when doing a fresh install, that is.

This is certainly an area where Linux can be improved - identifying hardware changes. It would be nice to have a command that does something like: "re-identify all hardware please, ignoring all previous data, as if this is a completely new installation."

Sorry it took me more than several weeks to re-install my Ubuntu based workstation. I was simply working around the clock to meet some pressing deadline and couldn't afford the risk of loosing precious time should the installation go wrong.

Thank you all for your help and insight. I think that this was a very interesting lesson (for me, at least).

Alex

P.S. The two HDDs are configured as two distinct RAID arrays - each "array" having a single drive.