[PATCH 1/2] dmaengine: hdmac: factorise memset descriptor allocation
From: Vinod Koul <hidden>
Date: 2015-10-07 13:56:16
Also in:
lkml
On Thu, Oct 01, 2015 at 04:52:37PM +0200, Maxime Ripard wrote:
+static struct at_desc *atc_create_memset_desc(struct dma_chan *chan,
+ dma_addr_t psrc,
+ dma_addr_t pdst,
+ size_t len)
+{
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+ struct at_desc *desc;
+ size_t xfer_count;
+
+ u32 ctrla = ATC_SRC_WIDTH(2) |
+ ATC_DST_WIDTH(2);why is this over two lines :)
+ u32 ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN |
+ ATC_SRC_ADDR_MODE_FIXED |
+ ATC_DST_ADDR_MODE_INCR |
+ ATC_FC_MEM2MEM;
+
+ xfer_count = len >> 2;
+ if (xfer_count > ATC_BTSIZE_MAX) {
+ dev_err(chan2dev(chan), "%s: buffer is too big\n",
+ __func__);
+ return NULL;
+ }This is fine, but this is driver limitation. We should really split the txn to multiple descriptors here..
quoted hunk ↗ jump to hunk
@@ -914,46 +953,26 @@ atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, return NULL; } - xfer_count = len >> 2; - if (xfer_count > ATC_BTSIZE_MAX) { - dev_err(chan2dev(chan), "%s: buffer is too big\n", + vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, &paddr);
Mostly people use _zalloc variant, any reason why you don't want that -- ~Vinod