Commit 585d3545 authored by Serge Semin's avatar Serge Semin Committed by Vinod Koul

dmaengine: dw: Initialize min and max burst DMA device capability

According to the DW APB DMAC data book the minimum burst transaction
length is 1 and it's true for any version of the controller since
isn't parametrised in the coreAssembler so can't be changed at the
IP-core synthesis stage. The maximum burst transaction can vary from
channel to channel and from controller to controller depending on a
IP-core parameter the system engineer activated during the IP-core
synthesis. Let's initialise both min_burst and max_burst members of the
DMA controller descriptor with extreme values so the DMA clients could
use them to properly optimize the DMA requests. The channels and
controller-specific max_burst length initialization will be introduced
by the follow-up patches.
Signed-off-by: default avatarSerge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723005848.31907-9-Sergey.Semin@baikalelectronics.ruSigned-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent e6fe5767
...@@ -1223,6 +1223,8 @@ int do_dma_probe(struct dw_dma_chip *chip) ...@@ -1223,6 +1223,8 @@ int do_dma_probe(struct dw_dma_chip *chip)
dw->dma.device_issue_pending = dwc_issue_pending; dw->dma.device_issue_pending = dwc_issue_pending;
/* DMA capabilities */ /* DMA capabilities */
dw->dma.min_burst = DW_DMA_MIN_BURST;
dw->dma.max_burst = DW_DMA_MAX_BURST;
dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS; dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS;
dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS; dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS;
dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) | dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) |
......
...@@ -12,6 +12,8 @@ ...@@ -12,6 +12,8 @@
#define DW_DMA_MAX_NR_MASTERS 4 #define DW_DMA_MAX_NR_MASTERS 4
#define DW_DMA_MAX_NR_CHANNELS 8 #define DW_DMA_MAX_NR_CHANNELS 8
#define DW_DMA_MIN_BURST 1
#define DW_DMA_MAX_BURST 256
/** /**
* struct dw_dma_slave - Controller-specific information about a slave * struct dw_dma_slave - Controller-specific information about a slave
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment