diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2019-07-22 15:44:45 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2019-07-22 18:28:15 +0300 |
| commit | 6f4722b1d1ebf274deb0459a36fad57a7d7fab31 (patch) | |
| tree | cc8bc2f7a343dd689fc92ccc896dffb1b904017e /drivers/dma | |
| parent | 756c3ef93492af382c541e039c1417b96a3d335e (diff) | |
| download | linux-6f4722b1d1ebf274deb0459a36fad57a7d7fab31.tar.xz | |
dmaengine: dw-edma: fix endianess confusion
When building with 'make C=1', sparse reports an endianess bug:
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:60:30: warning: cast removes address space of expression
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: expected void const volatile [noderef] <asn:2>*addr
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: got void *[assigned] ptr
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: expected void const volatile [noderef] <asn:2>*addr
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: got void *[assigned] ptr
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: warning: incorrect type in argument 1 (different address spaces)
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: expected void const volatile [noderef] <asn:2>*addr
drivers/dma/dw-edma/dw-edma-v0-debugfs.c:86:24: got void *[assigned] ptr
The current code is clearly wrong, as it passes an endian-swapped word
into a register function where it gets swapped again. Just pass the variables
directly into lower_32_bits()/upper_32_bits().
Fixes: 7e4b8a4fbe2c ("dmaengine: Add Synopsys eDMA IP version 0 support")
Link: https://lore.kernel.org/lkml/20190617131820.2470686-1-arnd@arndb.de/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Link: https://lore.kernel.org/r/20190722124457.1093886-3-arnd@arndb.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/dw-edma/dw-edma-v0-core.c | 24 |
1 files changed, 10 insertions, 14 deletions
diff --git a/drivers/dma/dw-edma/dw-edma-v0-core.c b/drivers/dma/dw-edma/dw-edma-v0-core.c index 97e3fd41c8a8..692de47b1670 100644 --- a/drivers/dma/dw-edma/dw-edma-v0-core.c +++ b/drivers/dma/dw-edma/dw-edma-v0-core.c @@ -195,7 +195,6 @@ static void dw_edma_v0_core_write_chunk(struct dw_edma_chunk *chunk) struct dw_edma_v0_lli __iomem *lli; struct dw_edma_v0_llp __iomem *llp; u32 control = 0, i = 0; - u64 sar, dar, addr; int j; lli = chunk->ll_region.vaddr; @@ -214,13 +213,11 @@ static void dw_edma_v0_core_write_chunk(struct dw_edma_chunk *chunk) /* Transfer size */ SET_LL(&lli[i].transfer_size, child->sz); /* SAR - low, high */ - sar = cpu_to_le64(child->sar); - SET_LL(&lli[i].sar_low, lower_32_bits(sar)); - SET_LL(&lli[i].sar_high, upper_32_bits(sar)); + SET_LL(&lli[i].sar_low, lower_32_bits(child->sar)); + SET_LL(&lli[i].sar_high, upper_32_bits(child->sar)); /* DAR - low, high */ - dar = cpu_to_le64(child->dar); - SET_LL(&lli[i].dar_low, lower_32_bits(dar)); - SET_LL(&lli[i].dar_high, upper_32_bits(dar)); + SET_LL(&lli[i].dar_low, lower_32_bits(child->dar)); + SET_LL(&lli[i].dar_high, upper_32_bits(child->dar)); i++; } @@ -232,9 +229,8 @@ static void dw_edma_v0_core_write_chunk(struct dw_edma_chunk *chunk) /* Channel control */ SET_LL(&llp->control, control); /* Linked list - low, high */ - addr = cpu_to_le64(chunk->ll_region.paddr); - SET_LL(&llp->llp_low, lower_32_bits(addr)); - SET_LL(&llp->llp_high, upper_32_bits(addr)); + SET_LL(&llp->llp_low, lower_32_bits(chunk->ll_region.paddr)); + SET_LL(&llp->llp_high, upper_32_bits(chunk->ll_region.paddr)); } void dw_edma_v0_core_start(struct dw_edma_chunk *chunk, bool first) @@ -242,7 +238,6 @@ 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->chip->dw; u32 tmp; - u64 llp; dw_edma_v0_core_write_chunk(chunk); @@ -262,9 +257,10 @@ 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 */ - llp = cpu_to_le64(chunk->ll_region.paddr); - SET_CH(dw, chan->dir, chan->id, llp_low, lower_32_bits(llp)); - SET_CH(dw, chan->dir, chan->id, llp_high, upper_32_bits(llp)); + 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)); } /* Doorbell */ SET_RW(dw, chan->dir, doorbell, |