The PDC driver is a mailbox controller. A mailbox controller
can report that a mailbox message has been "transmitted" either when
a tx interrupt fires or by having the mailbox framework poll. This
commit converts the PDC driver to the poll method. We found that the
tx interrupt happens when the descriptors are read by the SPU hw. Thus,
the interrupt method does not allow more than one tx message in the PDC
tx DMA ring at a time. To keep the SPU hw busy, we would like to keep
the tx ring full under heavy load.
With the poll method, the PDC driver responds that the previous message
has been transmitted if the tx ring has space for another message.
SPU request messages take a variable number of descriptors. If 15
descriptors are available, there is a good chance another message will
fit. Also increased the ring size from 128 to 512 descriptors.
With this change, I found the PDC driver hangs on its spinlock under
heavy load. The PDC spinlock is not required; so I removed it. Calls
to pdc_send_data() are already synchronized because of the channel
spinlock in the mailbox framework. Other references to ring indexes
should not require locking because they only written on either the
tx or rx side.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Minor fix to ensure that debugfs stats pseudo-files are
removed when driver module is unloaded. Previously, the call to
debugfs_remove_recursive() was never being called since the
directory was not empty, and a seg fault would occur if another
process tried to access these leftover files.
Signed-off-by: Steve Lin <steven.lin1@broadcom.com>
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Ensure that DMA is disabled, and pointers reset, when changing
DMA base addresses in pdc_ring_init(). This allows a mailbox client
to be re-inserted after being removed. Otherwise, the DMA doesn't
restart so the client hangs while being reinserted.
Signed-off-by: Steve Lin <steven.lin1@broadcom.com>
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
When creating the debugfs files for the PDC driver, use
octal file permissions rather than symbolic file permissions.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
We get 2 warnings when biuld kernel with W=1:
drivers/mailbox/bcm-pdc-mailbox.c:472:6: warning: no previous prototype for 'pdc_setup_debugfs' [-Wmissing-prototypes]
drivers/mailbox/bcm-pdc-mailbox.c:488:6: warning: no previous prototype for 'pdc_free_debugfs' [-Wmissing-prototypes]
In fact, these functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.
so this patch marks these functions with 'static'.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
We can't pass NULL pointers to pdc_ring_free() so I moved the check for
NULL.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Fix format and type mismatches in a couple debug prints in the
Broadcom PDC driver. Use %pad for dma_addr_t and %pa for
resource_size_t.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
The Broadcom PDC mailbox driver is a mailbox controller that
manages data transfers to and from one or more offload engines.
Signed-off-by: Rob Rice <rob.rice@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Rob Rice