Sifive platform dma (sf-pdma) has both in-order and out-of-order
configurations but sf-pdam driver configured to do in-order DMA
transfers, with out-of-order configuration got better throughput
in the PolarFire SoC platform.
Add a PolarFire SoC specific compatible and code to support
for out-of-order dma transfers
Reviewed-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Signed-off-by: Shravan Chippa <shravan.chippa@microchip.com>
Link: https://lore.kernel.org/r/20231208103856.3732998-4-shravan.chippa@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct sf_pdma.
[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
Cc: Vinod Koul <vkoul@kernel.org>
Cc: Green Wan <green.wan@sifive.com>
Cc: dmaengine@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230817235859.49846-9-keescook@chromium.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a
DMA channel") changed sf_pdma_prep_dma_memcpy() to unconditionally
allocate a new sf_pdma_desc each time it is called.
The driver previously recycled descs, by checking the in_use flag, only
allocating additional descs if the existing one was in use. This logic
was removed in commit b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread
support for a DMA channel"), but sf_pdma_free_desc() was not changed to
handle the new behaviour.
As a result, each time sf_pdma_prep_dma_memcpy() is called, the previous
descriptor is leaked, over time leading to memory starvation:
unreferenced object 0xffffffe008447300 (size 192):
comm "irq/39-mchp_dsc", pid 343, jiffies 4294906910 (age 981.200s)
hex dump (first 32 bytes):
00 00 00 ff 00 00 00 00 b8 c1 00 00 00 00 00 00 ................
00 00 70 08 10 00 00 00 00 00 00 c0 00 00 00 00 ..p.............
backtrace:
[<00000000064a04f4>] kmemleak_alloc+0x1e/0x28
[<00000000018927a7>] kmem_cache_alloc+0x11e/0x178
[<000000002aea8d16>] sf_pdma_prep_dma_memcpy+0x40/0x112
Add the missing kfree() to sf_pdma_free_desc(), and remove the redundant
in_use flag.
Fixes: b2cc5c465c2c ("dmaengine: sf-pdma: Add multithread support for a DMA channel")
Signed-off-by: Shravan Chippa <shravan.chippa@microchip.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230120100623.3530634-1-shravan.chippa@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
It currently assumes that there are always four channels, it would
cause the error if there is actually less than four channels. Change
that by getting number of channel from device tree.
For backwards-compatibility, it uses the default value (i.e. 4) when
there is no 'dma-channels' information in dts.
Signed-off-by: Zong Li <zong.li@sifive.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Link: https://lore.kernel.org/r/f08a95b6582a51712c5b2c3cb859136d07bfa8b9.1648461096.git.zong.li@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The place where the macro, SF_PDMA_REG_BASE(), is cause kernel-doc
using wrong function declaration. Move it to header file.
Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-2-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There are several comments starting from "/**" but not for function
comment purpose. It causes kernel-doc parsing wrong string. Replace
"/**" with "/*" to fix them.
Signed-off-by: Green Wan <green.wan@sifive.com>
Link: https://lore.kernel.org/r/20191118143554.16129-1-green.wan@sifive.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
