EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe On 12/03/2020 08:49, Jinpu Wang wrote: > On Wed, Mar 11, 2020 at 11:13 PM Douglas Gilbert <dgilbert@xxxxxxxxxxxx> wrote: >> >> On 2020-03-11 1:08 p.m., Jinpu Wang wrote: >>> On Tue, Jan 28, 2020 at 10:43 AM <Deepak.Ukey@xxxxxxxxxxxxx> wrote: >>>> >>>> >>>> EXTERNAL EMAIL: Do not click links or open attachments unless you >>>> know the content is safe >>>> >>>> On 22/01/2020 08:50, Deepak.Ukey@xxxxxxxxxxxxx wrote: >>>>> -r--r--r-- 1 root root 4096 Jan 21 12:05 >>>>> running_disparity_error_count >>>>> *** >>>>> -r--r--r-- 1 root root 4096 Jan 21 12:05 sas_address >>>>> lrwxrwxrwx 1 root root 0 Jan 21 11:45 subsystem -> >>>>> ../../../../../../../class/sas_phy >>>>> -r--r--r-- 1 root root 4096 Jan 21 12:05 target_port_protocols >>>>> -rw-r--r-- 1 root root 4096 Jan 21 11:45 uevent >>>>> >>>>> Maybe the other stuff provided in the patches are useful, I don't know. >>>>> But debugfs seems better for that. >>>>> >>>>> - 0006-pm80xx-sysfs-attribute-for-number-of-phys >>>>> - 0007-pm80xx-IOCTL-functionality-to-get-phy-status gets things like Programmed Link Rate, Negotiated Link Rate, PHY Identifier >>>>> - 0008-pm80xx-IOCTL-functionality-to-get-phy-error provides other things like Invalid Dword Error Count, Disparity Error Count >>>>> - Thanks for addressing it. We can get this info from /sys/class/sas_phy and /sys/class/sas_port so we will drop these above mentioned three patches from the next - patch series. >>>>> >>> >>>>> >>>>> - 0009-pm80xx-IOCTL-functionality-for-GPIO >>>>> - 0013-pm80xx-IOCTL-functionality-for-TWI-device >>>>> - For the above patches management utility passes command specific information to driver through IOCTL structure, which used by driver to frame the command and - send to FW. We are using the IOCTL interface for the same. Please let us know your thought. >>>> >>>> So I specifically questioned the SGPIO patch and why it would have an IOCTL, as this function is supported in kernel libsas/SAS transport code as an SMP function. >>>>> Thank you for your suggestions. We will make use of function supported in libsas. >>> >>> So basically you only need IOCTL for GPIO and TWI devices, others >>> can implement via libsas interface or from sysfs directly. >>> >>> I would like to suggest you do send out other changes without the >>> IOCTL parts first, and consider again Is it really needed by the >>> user to control GPIO and TWI, and if there is other way to do it? >>> >>> Sorry, I don't have a better suggestion! >> >> LSI SAS HBAs (LSI now owned by Broadcom) implement an internal ** SMP >> target. It can be seen here: >> >> # ls /dev/bsg >> 3:0:0:0 3:0:3:0 8:0:0:0 8:0:0:3 end_device-3:1 expander-3:0 >> 3:0:1:0 4:0:0:0 8:0:0:1 8:0:0:4 end_device-3:1:0 expander-3:1 >> 3:0:2:0 7:0:0:0 8:0:0:2 end_device-3:0:1 end_device-3:2 sas_host3 >> >> It is the last device node: "sas_host3". How do I know it is a SMP target? >> Because this works: >> >> # smp_read_gpio /dev/bsg/sas_host3 >> Read GPIO register response: >> GPIO_CFG[0]: >> version: 0 >> GPIO enable: 1 >> cfg register count: 2 >> gp register count: 1 >> supported drive count: 16 >> JFYI, that specific command is not implemented for libsas SMP host handler (see https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/scsi/libsas/sas_host_smp.c?h=v5.6-rc5#n278), but the write command should be ok >> When you work out what LSI are doing with this, perhaps you could >> write an article about it and make it publicly available. Firmware magic... >> It is always a good idea to see how your competitors solve problems >> :-) > This sounds indeed a better solution, thanks for the info, Doug > > @Deepak Ukey can you check if you guys can also do it this way? We are going to submit the version 3 of the patchset without IOCTL patches and in future we will come up with the different solution for IOCTL patches. Also we will go through the solution suggested by Doug. > > Regards, > Deepak > . >
