When the kernel is built with lockdep support and the owl-dma driver is
used, the following message is shown:
[ 2.496939] INFO: trying to register non-static key.
[ 2.501889] the code is fine but needs lockdep annotation.
[ 2.507357] turning off the locking correctness validator.
[ 2.512834] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.3+ #15
[ 2.519084] Hardware name: Generic DT based system
[ 2.523878] Workqueue: events_freezable mmc_rescan
[ 2.528681] [<801127f0>] (unwind_backtrace) from [<8010da58>] (show_stack+0x10/0x14)
[ 2.536420] [<8010da58>] (show_stack) from [<8080fbe8>] (dump_stack+0xb4/0xe0)
[ 2.543645] [<8080fbe8>] (dump_stack) from [<8017efa4>] (register_lock_class+0x6f0/0x718)
[ 2.551816] [<8017efa4>] (register_lock_class) from [<8017b7d0>] (__lock_acquire+0x78/0x25f0)
[ 2.560330] [<8017b7d0>] (__lock_acquire) from [<8017e5e4>] (lock_acquire+0xd8/0x1f4)
[ 2.568159] [<8017e5e4>] (lock_acquire) from [<80831fb0>] (_raw_spin_lock_irqsave+0x3c/0x50)
[ 2.576589] [<80831fb0>] (_raw_spin_lock_irqsave) from [<8051b5fc>] (owl_dma_issue_pending+0xbc/0x120)
[ 2.585884] [<8051b5fc>] (owl_dma_issue_pending) from [<80668cbc>] (owl_mmc_request+0x1b0/0x390)
[ 2.594655] [<80668cbc>] (owl_mmc_request) from [<80650ce0>] (mmc_start_request+0x94/0xbc)
[ 2.602906] [<80650ce0>] (mmc_start_request) from [<80650ec0>] (mmc_wait_for_req+0x64/0xd0)
[ 2.611245] [<80650ec0>] (mmc_wait_for_req) from [<8065aa10>] (mmc_app_send_scr+0x10c/0x144)
[ 2.619669] [<8065aa10>] (mmc_app_send_scr) from [<80659b3c>] (mmc_sd_setup_card+0x4c/0x318)
[ 2.628092] [<80659b3c>] (mmc_sd_setup_card) from [<80659f0c>] (mmc_sd_init_card+0x104/0x430)
[ 2.636601] [<80659f0c>] (mmc_sd_init_card) from [<8065a3e0>] (mmc_attach_sd+0xcc/0x16c)
[ 2.644678] [<8065a3e0>] (mmc_attach_sd) from [<8065301c>] (mmc_rescan+0x3ac/0x40c)
[ 2.652332] [<8065301c>] (mmc_rescan) from [<80143244>] (process_one_work+0x2d8/0x780)
[ 2.660239] [<80143244>] (process_one_work) from [<80143730>] (worker_thread+0x44/0x598)
[ 2.668323] [<80143730>] (worker_thread) from [<8014b5f8>] (kthread+0x148/0x150)
[ 2.675708] [<8014b5f8>] (kthread) from [<801010b4>] (ret_from_fork+0x14/0x20)
[ 2.682912] Exception stack(0xee8fdfb0 to 0xee8fdff8)
[ 2.687954] dfa0: 00000000 00000000 00000000 00000000
[ 2.696118] dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[ 2.704277] dfe0: 00000000 00000000 00000000 00000000 00000013 00000000
The obvious fix would be to use 'spin_lock_init()' on 'pchan->lock'
before attempting to call 'spin_lock_irqsave()' in 'owl_dma_get_pchan()'.
However, according to Manivannan Sadhasivam, 'pchan->lock' was supposed
to only protect 'pchan->vchan' while 'od->lock' does a similar job in
'owl_dma_terminate_pchan()'.
Therefore, this patch substitutes 'pchan->lock' with 'od->lock' and
removes the 'lock' attribute in 'owl_dma_pchan' struct.
Fixes: 47e20577c2 ("dmaengine: Add Actions Semi Owl family S900 DMA driver")
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Andreas Färber <afaerber@suse.de>
Link: https://lore.kernel.org/r/c6e6cdaca252b5364bd294093673951036488cf0.1588439073.git.cristian.ciocaltea@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Originally freeing descriptors was split into a locked and an unlocked
part. The locked part in vchan_get_all_descriptors() collected all
descriptors on a separate list_head. This was done to allow iterating
over that new list in vchan_dma_desc_free_list() without a lock held.
This became broken in 13bb26ae88 ("dmaengine: virt-dma: don't always
free descriptor upon completion"). With this commit
vchan_dma_desc_free_list() no longer exclusively operates on the
separate list, but starts to put descriptors which can be reused back on
&vc->desc_allocated. This list operation should have been locked, but
wasn't.
In the mean time drivers started to call vchan_dma_desc_free_list() with
their lock held so that we now have the situation that
vchan_dma_desc_free_list() is called locked from some drivers and
unlocked from others.
To clean this up we have to do two things:
1. Add missing locking in vchan_dma_desc_free_list()
2. Make sure drivers call vchan_dma_desc_free_list() unlocked
This needs to be done atomically, so in this patch the locking is added
and all drivers are fixed.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Green Wan <green.wan@sifive.com>
Tested-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191216105328.15198-3-s.hauer@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Simplify this function implementation by using a known wrapper function.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/d36b6a6c-2e3d-8d68-6ddc-969a377ca3b2@web.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Following warnings are generated when compiled with W=1,
drivers/dma/owl-dma.c:170: warning: Function parameter or member 'cyclic'
not described in 'owl_dma_txd'
drivers/dma/owl-dma.c:198: warning: Function parameter or member 'cfg' not
described in 'owl_dma_vchan'
drivers/dma/owl-dma.c:198: warning: Function parameter or member 'drq' not
described in 'owl_dma_vchan'
drivers/dma/owl-dma.c:225: warning: Function parameter or member 'irq' not
described in 'owl_dma'
Fix this by adding comments for relevant struct members to appear in
kernel-doc.
Fixes: d64e1b3f5c ("dmaengine: owl: Add Slave and Cyclic mode support for
Actions Semi Owl S900 SoC")
Reported-by: Vinod Koul <vinod.koul@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add Slave and Cyclic mode support for Actions Semi Owl S900 SoC. The slave
mode supports bus width of 4 bytes common for all peripherals and 1 byte
specific for UART.
The cyclic mode supports only block mode transfer.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Cristian Ciocaltea
Sascha Hauer
Markus Elfring
Manivannan Sadhasivam