ARCv3: Add CDMA support driver #138
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| a = handle >> 5; | ||
| o = 1 << (handle & 0x1f); |
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Let's not use these magic numbers and have proper defines instead (bits mask / bits shift)
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| a = handle >> 5; | ||
| x = 1 << (handle & 0x1f); |
| u32 len, /* DMA length in bytes */ | ||
| struct cdma_c_attr_t a) /* Attributes */ | ||
| { | ||
| /* Write will block iff busy i.e. DMA_C_STATUS_AUX.B bit is set */ |
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| /* Write will block iff busy i.e. DMA_C_STATUS_AUX.B bit is set */ | |
| /* Write will block if busy i.e. DMA_C_STATUS_AUX.B bit is set */ |
| struct cdma_hw_desc *hw_desc; | ||
| unsigned long flags; | ||
| int done_flg; | ||
| int entry_notfound = 1; |
| */ | ||
| for (ii = 0; ii < dw->nr_channels; ii++) { | ||
| chan = &dw->channels[ii]; | ||
| dev_warn(chan2dev(chan), "WARN. Channel is overflowed.\n"); |
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probably we can remove 'WARN' from comment - this info is provided by dev_warn. Same for dev_err
| u32 tmp; | ||
|
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| bcr.val = read_aux_reg(DMA_BUILD); | ||
| if (bcr.ver < 0x10) |
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Magic number. Probably we can name it as DW_CDMA_MIN_VERSION or something like that.
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| /* vv = (u32)(src >> 32ULL); */ | ||
| /* WRITE_AUX(DMA_C_SRC_HI_AUX, vv); */ | ||
| /* vv = (u32)(dst >> 32ULL); */ | ||
| /* WRITE_AUX(DMA_C_DST_HI_AUX, vv); */ |
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This is suspicious as we set DMA_BIT_MASK(64)
drivers/dma/dw-cdma/dw-cdma.h
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| struct dw_cluster_dma { | ||
| struct dma_device dma; | ||
| struct device_dma_parameters dma_parms; | ||
| int nr_channels; |
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Extra tab. I'd expect that it should be detected by checkpatch.
drivers/dma/dw-cdma/dw-cdma.h
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| struct cdma_chip { | ||
| struct device *dev; | ||
| struct dw_cluster_dma *dw; | ||
| int irq; |
| a = handle >> 5; | ||
| o = 1 << (handle & 0x1f); | ||
| READ_BCR(DMA_S_DONESTATD_AUX(a), x); | ||
| x = x & o; |
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| x = x & o; | |
| x &= o; |
xxkent
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Driver to support Cluster DMA(CDMA) controller for ARCv3. For HS58 tested on nSIM and HAPS using 'dmatest' driver. For HS68 tested on nSIM using 'dmatest' driver. Known limitations: Don't specify 'test_buf_size' 'dmatest' parameter more then 750000 when L2$ is enabled. Looks like L2$ operations in cache-arcv3.c:scm_op_rgn() fails when sz > 750000. Probably it is restriction in HW. Otherwise the kernel will crash.
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Driver to support Cluster DMA(CDMA) controller for ARCv3. For HS58 tested on nSIM and HAPS using 'dmatest' driver. For HS68 tested on nSIM using 'dmatest' driver.
Known limitations:
Don't specify 'test_buf_size' 'dmatest' parameter more then 750000 when L2$ is enabled. Looks like L2$ operations in cache-arcv3.c:scm_op_rgn() fails when sz > 750000. Probably it is restriction in HW. Otherwise the kernel will crash.