github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-27 01:32:21 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

dmaengine: dw-edma: Add spinlock to protect DONE_INT_MASK and ABORT_INT_MASK

Browse Source 
The DONE_INT_MASK and ABORT_INT_MASK registers are shared by all DMA
channels, and modifying them requires a read-modify-write sequence.
Because this operation is not atomic, concurrent calls to
dw_edma_v0_core_start() can introduce race conditions if two channels
update these registers simultaneously.

Add a spinlock to serialize access to these registers and prevent race
conditions.

Fixes: 7e4b8a4fbe ("dmaengine: Add Synopsys eDMA IP version 0 support")
Cc: stable@vger.kernel.org
Signed-off-by: Frank Li <Frank.Li@nxp.com>
[den: update dw_edma.lock comment]
Link: https://lore.kernel.org/dmaengine/20260109-edma_ll-v2-1-5c0b27b2c664@nxp.com/
Signed-off-by: Koichiro Den <den@valinux.co.jp>
Link: https://patch.msgid.link/20260521142153.2957432-5-den@valinux.co.jp
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Frank Li 2026-05-21 23:21:53 +09:00 committed by Vinod Koul
parent 11d7cfe0c1
commit 8ffba0171c
2 changed files with 7 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/dma/dw-edma/dw-edma-core.h
View File

@ -109,7 +109,7 @@ struct dw_edma {
struct dw_edma_chan *chan;
raw_spinlock_t lock; /* Only for legacy */
raw_spinlock_t lock; /* Protect v0 shared registers */
struct dw_edma_chip *chip;

6
drivers/dma/dw-edma/dw-edma-v0-core.c
View File

@ -364,6 +364,7 @@ static void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
{
struct dw_edma_chan *chan = chunk->chan;
struct dw_edma *dw = chan->dw;
unsigned long flags;
u32 tmp;
dw_edma_v0_core_write_chunk(chunk);
@ -408,6 +409,8 @@ static void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
}
}
/* Interrupt unmask - done, abort */
raw_spin_lock_irqsave(&dw->lock, flags);
tmp = GET_RW_32(dw, chan->dir, int_mask);
tmp &= ~FIELD_PREP(EDMA_V0_DONE_INT_MASK, BIT(chan->id));
tmp &= ~FIELD_PREP(EDMA_V0_ABORT_INT_MASK, BIT(chan->id));
@ -416,6 +419,9 @@ static void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
tmp = GET_RW_32(dw, chan->dir, linked_list_err_en);
tmp |= FIELD_PREP(EDMA_V0_LINKED_LIST_ERR_MASK, BIT(chan->id));
SET_RW_32(dw, chan->dir, linked_list_err_en, tmp);
raw_spin_unlock_irqrestore(&dw->lock, flags);
/* Channel control */
SET_CH_32(dw, chan->dir, chan->id, ch_control1,
(DW_EDMA_V0_CCS | DW_EDMA_V0_LLE));