[PATCH] dmaengine: dw-edma: Fix linked list physical address calculation on non-64 bits architectures

Gustavo Pimentel
2020-08-13T14:14:01Z

Fix linked list physical address calculation on non-64 bits architectures.

The paddr variable is phys_addr_t type, which can assume a different
type (u64 or u32) depending on the conditional compilation flag
CONFIG_PHYS_ADDR_T_64BIT.

Since this variable is used in with upper_32 bits() macro to get the
value from 32 to 63 bits, on a non-64 bits architecture this variable
will assume a u32 type, it can cause a compilation warning.

This issue was reported by a Coverity analysis.

Fixes: 7e4b8a4fbe2c ("dmaengine: Add Synopsys eDMA IP version 0 support")

Cc: Joao Pinto <jpinto@synopsys.com>
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
---
drivers/dma/dw-edma/dw-edma-v0-core.c | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/dw-edma/dw-edma-v0-core.c b/drivers/dma/dw-edma/dw-edma-v0-core.c
index 692de47..cfabbf5 100644
--- a/drivers/dma/dw-edma/dw-edma-v0-core.c
+++ b/drivers/dma/dw-edma/dw-edma-v0-core.c
@@ -229,8 +229,13 @@ static void dw_edma_v0_core_write_chunk(struct dw_edma_chunk *chunk)
/* Channel control */
SET_LL(&llp->control, control);
/* Linked list - low, high */
- SET_LL(&llp->llp_low, lower_32_bits(chunk->ll_region.paddr));
- SET_LL(&llp->llp_high, upper_32_bits(chunk->ll_region.paddr));
+ #ifdef CONFIG_PHYS_ADDR_T_64BIT
+ SET_LL(&llp->llp_low, lower_32_bits(chunk->ll_region.paddr));
+ SET_LL(&llp->llp_high, upper_32_bits(chunk->ll_region.paddr));
+ #else /* CONFIG_PHYS_ADDR_T_64BIT */
+ SET_LL(&llp->llp_low, chunk->ll_region.paddr);
+ SET_LL(&llp->llp_high, 0x0);
+ #endif /* CONFIG_PHYS_ADDR_T_64BIT */
}

void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
@@ -257,10 +262,16 @@ void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first)
SET_CH(dw, chan->dir, chan->id, ch_control1,
(DW_EDMA_V0_CCS | DW_EDMA_V0_LLE));
/* Linked list - low, high */
- SET_CH(dw, chan->dir, chan->id, llp_low,
- lower_32_bits(chunk->ll_region.paddr));
- SET_CH(dw, chan->dir, chan->id, llp_high,
- upper_32_bits(chunk->ll_region.paddr));
+ #ifdef CONFIG_PHYS_ADDR_T_64BIT
+ SET_CH(dw, chan->dir, chan->id, llp_low,
+ lower_32_bits(chunk->ll_region.paddr));
+ SET_CH(dw, chan->dir, chan->id, llp_high,
+ upper_32_bits(chunk->ll_region.paddr));
+ #else /* CONFIG_PHYS_ADDR_T_64BIT */
+ SET_CH(dw, chan->dir, chan->id, llp_low,
+ chunk->ll_region.paddr);
+ SET_CH(dw, chan->dir, chan->id, llp_high, 0x0);
+ #endif /* CONFIG_PHYS_ADDR_T_64BIT*/
}
/* Doorbell */
SET_RW(dw, chan->dir, doorbell,
--
2.7.4