[PATCH v7 02/11] dt-bindings: dma: dw: Add max burst transaction length property

Serge Semin
2020-07-09T22:47:09Z

This array property is used to indicate the maximum burst transaction
length supported by each DMA channel.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-mips@vger.kernel.org

---

Changelog v2:
- Rearrange SoBs.
- Move $ref to the root level of the properties. So do with the
constraints.
- Set default max-burst-len to 256 TR-WIDTH words.

Changelog v3:
- Add more details into the property description about what limitations
snps,max-burst-len defines.
---
.../bindings/dma/snps,dma-spear1340.yaml | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/dma/snps,dma-spear1340.yaml b/Documentation/devicetree/bindings/dma/snps,dma-spear1340.yaml
index e7611840a7cf..20870f5c14dd 100644
--- a/Documentation/devicetree/bindings/dma/snps,dma-spear1340.yaml
+++ b/Documentation/devicetree/bindings/dma/snps,dma-spear1340.yaml
@@ -120,6 +120,21 @@ properties:
enum: [0, 1]
default: 1

+ snps,max-burst-len:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: |
+ Maximum length of the burst transactions supported by the controller.
+ This property defines the upper limit of the run-time burst setting
+ (CTLx.SRC_MSIZE/CTLx.DST_MSIZE fields) so the allowed burst length
+ will be from 1 to max-burst-len words. It's an array property with one
+ cell per channel in the units determined by the value set in the
+ CTLx.SRC_TR_WIDTH/CTLx.DST_TR_WIDTH fields (data width).
+ items:
+ maxItems: 8
+ items:
+ enum: [4, 8, 16, 32, 64, 128, 256]
+ default: 256
+
snps,dma-protection-control:
$ref: /schemas/types.yaml#definitions/uint32
description: |
--
2.26.2