Commit graph

20 commits

Author SHA1 Message Date
Anup Patel
ecbf9ef15a dmaengine: bcm-sba-raid: Remove redundant SBA_REQUEST_STATE_COMPLETED
The SBA_REQUEST_STATE_COMPLETED state was added to keep track
of sba_request which got completed but cannot be freed because
underlying Async Tx descriptor was not ACKed by DMA client.

Instead of above, we can free the sba_request with non-ACKed
Async Tx descriptor and sba_alloc_request() will ensure that
it always allocates sba_request with ACKed Async Tx descriptor.
This alternate approach makes SBA_REQUEST_STATE_COMPLETED state
redundant hence this patch removes it.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
29e0f486d9 dmaengine: bcm-sba-raid: Explicitly ACK mailbox message after sending
We should explicitly ACK mailbox message because after
sending message we can know the send status via error
attribute of brcm_message.

This will also help SBA-RAID to use "txdone_ack" method
whenever mailbox controller supports it.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
8529a927e2 dmaengine: bcm-sba-raid: Add debugfs support
This patch adds debugfs support to report stats via debugfs
which in-turn will help debug hang or error situations.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
b99c238669 dmaengine: bcm-sba-raid: Remove redundant SBA_REQUEST_STATE_RECEIVED
The SBA_REQUEST_STATE_RECEIVED state is now redundant because
received sba_request are immediately freed or moved to completed
list in sba_process_received_request().

This patch removes redundant SBA_REQUEST_STATE_RECEIVED state.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
d6ffd2395a dmaengine: bcm-sba-raid: Re-factor sba_process_deferred_requests()
Currently, sba_process_deferred_requests() handles both pending
and completed sba_request which is unnecessary overhead for
sba_issue_pending() because completed sba_request handling is
not required in sba_issue_pending().

This patch breaks sba_process_deferred_requests() into two parts
sba_process_received_request() and _sba_process_pending_requests().

The sba_issue_pending() will only process pending sba_request
by calling _sba_process_pending_requests(). This will improve
sba_issue_pending().

The sba_receive_message() will only process received sba_request
by calling sba_process_received_request() for each received
sba_request. The sba_process_received_request() will also call
_sba_process_pending_requests() after handling received sba_request
because we might have pending sba_request not submitted by previous
call to sba_issue_pending().

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
fd8eb5395f dmaengine: bcm-sba-raid: Pre-ack async tx descriptor
We should pre-ack async tx descriptor at time of
allocating sba_request (just like other RAID drivers).

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
6df8f913d2 dmaengine: bcm-sba-raid: Peek mbox when we have no free requests
When setting up RAID array on several NVMe disks we observed that
sba_alloc_request() start failing (due to no free requests left)
and RAID array setup becomes very slow.

To improve performance, we do mbox channel peek when we have
no free requests. This improves performance of RAID array setup
because mbox requests that were completed but not processed by
mbox completion worker will be processed immediately by mbox
channel peek.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
eb67744b9a dmaengine: bcm-sba-raid: Alloc resources before registering DMA device
We should allocate DMA channel resources before registering the
DMA device in sba_probe() because we can get DMA request soon
after registering the DMA device. If DMA channel resources are
not allocated before first DMA request then SBA-RAID driver will
crash.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
f83385142c dmaengine: bcm-sba-raid: Improve sba_issue_pending() run duration
The pending sba_request list can become very long in real-life usage
(e.g. setting up RAID array) which can cause sba_issue_pending() to
run for long duration.

This patch adds common sba_process_deferred_requests() to process
few completed and pending requests so that it finishes in short
duration. We use this common sba_process_deferred_requests() in
both sba_issue_pending() and sba_receive_message().

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
5346aafcef dmaengine: bcm-sba-raid: Increase number of free sba_request
Currently, we have only 1024 free sba_request created
by sba_prealloc_channel_resources(). This is too low
and the prep_xxx() callbacks start failing more often
at time of RAID array setup over NVMe disks.

This patch sets number of free sba_request created by
sba_prealloc_channel_resources() to be:
<number_of_mailbox_channels> x 8192

Due to above, we will have sufficient number of free
sba_request and prep_xxx() callbacks failing is very
unlikely.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
5655e00f5c dmaengine: bcm-sba-raid: Allow arbitrary number free sba_request
Currently, we cannot have any arbitrary number of free sba_request
because sba_prealloc_channel_resources() allocates an array of
sba_request using devm_kcalloc() and kcalloc() cannot provide
memory beyond certain size.

This patch removes "reqs" (sba_request array) from sba_device
and makes "cmds" as variable array (instead of pointer) in
sba_request. This helps sba_prealloc_channel_resources() to
allocate sba_request and associated SBA command in one allocation
which in-turn allows arbitrary number of free sba_request.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
abfa251afe dmaengine: bcm-sba-raid: Remove reqs_free_count from sba_device
The reqs_free_count member of sba_device is not used anywhere
hence no point in tracking number of free sba_request.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
e7ae72aa65 dmaengine: bcm-sba-raid: Remove redundant resp_dma from sba_request
Both resp and resp_dma are redundant in sba_request because
resp is unused and resp_dma carries same information present
in tx.phys of sba_request. This patch removes both resp and
resp_dma from sba_request.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
10f1a33080 dmaengine: bcm-sba-raid: Remove redundant next_count from sba_request
The next_count in sba_request is redundant because same information
is captured by next_pending_count. This patch removes next_count
from sba_request.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
57a2850859 dmaengine: bcm-sba-raid: Common flags for sba_request state and fence
This patch merges sba_request state and fence into common
sba_request flags. The sba_request flags not only saves
memory but it can also be extended in-future without adding
new members.

We also make each sba_request state as separate bit in
sba_request flags to help debugging situations where a
sba_request is accidently in two states.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
e4274cfa42 dmaengine: bcm-sba-raid: Reduce locking context in sba_alloc_request()
We don't require to hold "sba->reqs_lock" for long-time
in sba_alloc_request() because lock protection is not
required when initializing members of "struct sba_request".

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Anup Patel
e897091ab9 dmaengine: bcm-sba-raid: Minor improvments in comments
This patch does following improvments to comments:
1. Make section comments consistent across the driver by
avoiding " SBA " in some of the comments
2. Add/update few more section comments

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-08-28 16:44:24 +05:30
Vinod Koul
dd2bceb0a8 dmaengine: bcm-scm-raid: statify functions
This driver builds with warnings which can be fixed by making these
functions static.

  CC [M]  drivers/dma/bcm-sba-raid.o
drivers/dma/bcm-sba-raid.c:786:1: warning: no previous prototype for ‘sba_prep_dma_xor_req’ [-Wmissing-prototypes]
 sba_prep_dma_xor_req(struct sba_device *sba,
 ^
drivers/dma/bcm-sba-raid.c:995:1: warning: no previous prototype for ‘sba_prep_dma_pq_req’ [-Wmissing-prototypes]
 sba_prep_dma_pq_req(struct sba_device *sba, dma_addr_t off,
 ^
drivers/dma/bcm-sba-raid.c:1247:1: warning: no previous prototype for ‘sba_prep_dma_pq_single_req’ [-Wmissing-prototypes]
 sba_prep_dma_pq_single_req(struct sba_device *sba, dma_addr_t off,
 ^

Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-07-19 10:03:24 +05:30
Colin Ian King
1fc63cb4f1 dmaengine: bcm-scm-raid: remove redundant null check on req
Req is never null on at the point of the null check, so
remove this redundant check and just return &req->tx.

Detected by CoverityScan, CID#1436147 ("Logically dead code")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-05-19 08:56:16 +05:30
Anup Patel
743e1c8ffe dmaengine: Add Broadcom SBA RAID driver
The Broadcom stream buffer accelerator (SBA) provides offloading
capabilities for RAID operations. This SBA offload engine is
accessible via Broadcom SoC specific ring manager.

This patch adds Broadcom SBA RAID driver which provides one
DMA device with RAID capabilities using one or more Broadcom
SoC specific ring manager channels. The SBA RAID driver in its
current shape implements memcpy, xor, and pq operations.

Signed-off-by: Anup Patel <anup.patel@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-05-16 10:01:57 +05:30