I'd like some clarifications:
Dos this driver support a set of hardware that is distinct from that
supported by megasas? I.e. no overlap between what drivers requiring
users to "choose" which driver to use for their hardware, right?
I seem to understand that this driver *only* supports drives configured
as a RAID, and doesn't support ordinary JBOD uses? So a drive used
with this controller can only be used with either megasas or another
instance of this driver. Right?
-- Garrett
Frank Che wrote:
> I'm sponsoring this fast track for Susan Scheufele and Yu Wu.
> Requested release binding is Patch. Timer is set to Mar 12, 2009.
>
> -Frank
>
> 2. Project Summary
>
> This project integrates LSI MegaRAID SAS2.0 Controller HBA driver,
> mr_sas, into Solaris. Requested Release binding is Patch.
>
> LSI's next generation of SAS2.0 HBA controllers will support a new
> driver based on the LSI's MegaRAID Firmware Interface (MFI).
> The driver was developed by LSI, and the driver capabilities are
> significantly upgraded from the previous generation driver, including
> dynamic enumeration, SMP support, Hot Plug for Disk and HBA, tape
> pass through, and a related kmdb module. The new driver supports
> the LSI SAS2108(Liberator) controller.
>
> 4. Technical Description:
>
> 4.1. Details:
>
> The mr_sas(7d) driver will support LSI's MegaRAID SAS2.0
> controllers, and will not support LSI's SAS1.0 controllers.
> The on-disk metadata format is compatible, so that MegaRAID
> drives can be moved from SAS1.0 to SAS2.0 controllers without
> fear of data loss, and vice versa.
>
> The mr_sas(7d) driver will be DDI and SCSAv2-complaint, as
> much as possible. The driver will provide new functionality compared
> to the existing megasas(7d) driver: dynamic enumeration, SMP,
> drive hot plug, and a related kmdb module. Additional software
> features are planned to be implemented by LSI and Sun in separate
> phases over the next year.
>
> 4.3. In Scope:
>
> The following features are supported in the initial version
> of the driver.
> X86 Support - starting with X86 due to limited hardware availability
> Sparc Support - available within 2 builds of the X86 support
> 64 bit DMA - normal HBA feature, was missing from gen1 driver
> initially
> Dynamic Enumeration - .conf file not required to attach logical
> drives
> SMP Enumeration - logical drives may be accessed via a SAS expander
> FMA level 2 support - checks for errors on DMA and PIO accesses
> Hot Plug of Drives - handled via the LSI management utilities
> MSI-X support - for MSI and MSI-X interrupts.
> Solaris quiesce - for fastboot support
> mdb walker - provides driver-related kmdb info
> Expander pass through - for specified SAS expanders
>
> 4.4. Out of Scope:
>
> The following features are planned as follow-on enhancements for
> the driver. They are not supported in the initial release
> of the driver due to time-to-market considerations.
> Tape pass through - for specified SAS tape drives
> Hot Plug of HBA - first RFE following Sparc, required for blades
> SMP Multipathing - requirements need further clarification,
> for load balancing and failover
> Power Management - LSI is investigating the fw support required
> Timeout support - LSI is investigating the fw support required
> PCI-E relaxed ordering - verified that the device supports it
> kstats - part of follow-on performance work
> kmem_cache_alloc - if performance testing warrants its usage
> fwflash plugin - firmware upgrade for the card and drives is already
> handled via the LSI management utilities
> FMA 2.5 support - support for LSI MegaRAID-specific error
> conditions,
> is already handled via the LSI management utilities
>
> The following features are not supported with mr_sas(7D):
> raidctl plugin - Sun has made a business choice to pass through
> the responsibility for the device configuration tools to the
> vendor (eg, LSI). There is no "value add" in adding the same
> capabilities that LSI provides today.
> MPXIO - generically does not work with RAID drivers
> JBOD passthrough - no near-term support for this feature is planned
> iPort code - only applies if there is JBOD passthrough support
> WWN registration of devices - no support for this feature is
> planned by LSI for this driver
>
> 4.5. Interfaces:
>
> The project exports the following interfaces:
>
> Interface Name Stability Comments
> --------------- --------------- -------------
> mr_sas(7D) Committed Driver name
> SUNWmrsas Committed Package name
>
>
> 4.6. Doc Impact:
>
> A man page will be created for the mr_sas(7d) driver.
>
> 4.7. Admin/Config Impact:
>
> The BIOS will be used to create RAID volumes for X86 platforms.
> There is a minimal Fcode interface that may be used to create
> RAID volumes for Sparc platforms. In addition, LSI's RAID
> configuration and management utilities are supported with this
> driver, and are available for download from LSI's website.
>
> 4.8. HA Impact:
>
> Not supported due to lack of MPXIO, which generically does not
> work with hardware RAID drivers.
>
> 4.10. Packaging & Delivery:
>
> The mr_sas(7d) driver will be delivered initially on the x86
> architectures, and shortly thereafter on Sparc. The mr_sas(7d)
> driver will be included as:
>
> /kernel/drv/mr_sas
> /kernel/drv/mr_sas.conf
> /kernel/drv/amd64/mr_sas
> /kernel/drv/sparcv9/mr_sas
>
> The mr_sas(7d) manpage will be included in SUNWman.
>
> 6. Resources and Schedule:
>
> 6.4. Product Approval Committee requested information:
> 6.4.1. Consolidation or Component Name: ON
>
> 6.5. ARC review type: Fast Track
>
> 6.6. ARC Exposure: open
>
>
