Hi James, I've noticed you haven't merged this patch. To avoid further problems I resent a V5 to this patch removing the Kconfig change. Dolev > On Thu, 2013-05-02 at 17:25 +0530, Santosh Y wrote: >> From: Dolev Raviv <draviv@xxxxxxxxxxxxxx> >> >> Add support for sending UFS query requests through tagged command >> queuing. This design allows queuing query requests in any open slot >> along with other SCSI commands. In this way there is no need to >> save a slot in the requests queue and decrease its size. >> >> A query request is posing to a SCSI command to use native flow. But >> unlike normal SCSI command flow, the data and response fields are >> filled in UFS host data structure instead of passing as arguments >> while queuing into SCSI mlqueue (mid-layer SCSI queue, the requests >> from this queue are submitted to the device queue). As per specification >> only one query request is allowed to be processed by device. Hence a >> mutex lock for protecting data and response fields (hba->query.request >> and >> hba->query.response) needs to be held while query request is in >> progress. >> >> The API for submitting a query request is ufs_query_request() in >> ufshcd.c. This function is responsible for: >> 1. Obtaining the SCSI device from the host >> 2. Keeping the query mutex to prevent multiple queries >> 3. Storing the required data for sending a query request in ufs_hba >> 4. Queuing a SCSI vendor specific command to trigger a query request >> in the UFS driver. >> >> The callers of ufs_query_request() are expected to fill the query >> command data fields and are to provide an allocated response field >> for the driver to fill response fields after request completion. >> >> The request and response upiu is extended in a union to enable using the >> same data structure, both for command upiu and query request upiu. >> >> The query request flow is separated from the scsi command flow in: >> 1. Preparing the request >> 2. Validating response (error) codes >> 3. Copying data (only used for descriptor read/write query requests) >> 4. Copying response/sense >> >> Data error can't be handled in the scsi command native flow. Hence, >> we pass the code as without a change back to the submitting layer. >> >> UPIU (UFS Protocol Information Unit) size is increased to 512 bytes >> from 128. The UPIU header and the transaction specific fields (SCSI >> command or Query Request OSF - Op-code Specific Fields) are 32 bytes >> together, the rest is used to transfer extra request data (such as >> descriptor in query requests). In order to accommodate the largest >> descriptor in the UFS spec (256 bytes) we need to increase the UPIU >> size. >> >> Signed-off-by: Dolev Raviv <draviv@xxxxxxxxxxxxxx> >> Signed-off-by: Santosh Y <santoshsy@xxxxxxxxx> >> >> diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig >> index 35faf24..82417d6 100644 >> --- a/drivers/scsi/ufs/Kconfig >> +++ b/drivers/scsi/ufs/Kconfig >> @@ -35,6 +35,7 @@ >> config SCSI_UFSHCD >> tristate "Universal Flash Storage Controller Driver Core" >> depends on SCSI >> + default y >> ---help--- >> This selects the support for UFS devices in Linux, say Y and make >> sure that you know the name of your UFS host adapter (the card > > I don't think you want to force this on in every configuration since > it's only appropriate to non server/desktop. I stripped this hunk. > > James > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
