diff options
| author | Frank Li <Frank.Li@nxp.com> | 2026-05-21 23:21:53 +0900 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-06-08 17:02:21 +0530 |
| commit | 8ffba0171c6bbce5f093c6dba5a02c0805b31203 (patch) | |
| tree | 091af11679982567bb9a65b539ae5bea3f8e95d5 | |
| parent | 11d7cfe0c119691b2dafbb699bbca90258c678aa (diff) | |
dmaengine: dw-edma: Add spinlock to protect DONE_INT_MASK and ABORT_INT_MASK
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: 7e4b8a4fbe2c ("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>
| -rw-r--r-- | drivers/dma/dw-edma/dw-edma-core.h | 2 | ||||
| -rw-r--r-- | drivers/dma/dw-edma/dw-edma-v0-core.c | 6 |
2 files changed, 7 insertions, 1 deletions
diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h index 902574b1ba86..6474cacf7195 100644 --- a/drivers/dma/dw-edma/dw-edma-core.h +++ b/drivers/dma/dw-edma/dw-edma-core.h @@ -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; diff --git a/drivers/dma/dw-edma/dw-edma-v0-core.c b/drivers/dma/dw-edma/dw-edma-v0-core.c index 69e8279adec8..cfdd6463252e 100644 --- a/drivers/dma/dw-edma/dw-edma-v0-core.c +++ b/drivers/dma/dw-edma/dw-edma-v0-core.c @@ -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)); |