Hi Marek,
Thanks for reviewing.
On 7/14/22 21:02, Marek Vasut wrote:
On 7/13/22 16:21, Amelie Delaunay wrote:
[...]
diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index adb25a11c70f..3916295fe154 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -142,6 +142,8 @@
#define STM32_DMA_DIRECT_MODE_GET(n) (((n) &
STM32_DMA_DIRECT_MODE_MASK) >> 2)
#define STM32_DMA_ALT_ACK_MODE_MASK BIT(4)
#define STM32_DMA_ALT_ACK_MODE_GET(n) (((n) &
STM32_DMA_ALT_ACK_MODE_MASK) >> 4)
+#define STM32_DMA_MDMA_STREAM_ID_MASK GENMASK(19, 16)
+#define STM32_DMA_MDMA_STREAM_ID_GET(n) (((n) &
STM32_DMA_MDMA_STREAM_ID_MASK) >> 16)
Try FIELD_GET() from include/linux/bitfield.h
[...]
Yes, but not only on this new line. I'll add a prior patch to the
patchset to use FIELD_{GET,PREP}() helpers every where custom macros are
used.
@@ -1630,6 +1670,20 @@ static int stm32_dma_probe(struct
platform_device *pdev)
chan->id = i;
chan->vchan.desc_free = stm32_dma_desc_free;
vchan_init(&chan->vchan, dd);
+
+ chan->mdma_config.ifcr = res->start;
+ chan->mdma_config.ifcr += (chan->id & 4) ? STM32_DMA_HIFCR :
STM32_DMA_LIFCR;
+
+ chan->mdma_config.tcf = STM32_DMA_TCI;
+ /*
+ * bit0 of chan->id represents the need to left shift by 6
+ * bit1 of chan->id represents the need to extra left shift
by 16
+ * TCIF0, chan->id = b0000; TCIF4, chan->id = b0100: left
shift by 0*6 + 0*16
+ * TCIF1, chan->id = b0001; TCIF5, chan->id = b0101: left
shift by 1*6 + 0*16
+ * TCIF2, chan->id = b0010; TCIF6, chan->id = b0110: left
shift by 0*6 + 1*16
+ * TCIF3, chan->id = b0011; TCIF7, chan->id = b0111: left
shift by 1*6 + 1*16
+ */
+ chan->mdma_config.tcf <<= (6 * (chan->id & 0x1) + 16 *
((chan->id & 0x2) >> 1));
Some sort of symbolic macros instead of open-coded constants could help
readability here.
I agree. As the same kind of computation is done in
stm32_dma_irq_status() and stm32_dma_irq_clear(), I'll add another prior
patch to the patchset to introduce new macro helpers to get ISR/IFCR
offset depending on channel id, and to get channel flags mask depending
on channel id.
[...]
Regards,
Amelie
