VideoEngine (cedrus) needs assign dedicated SRAM for decoding.
SRAM_C1 is usually used for Allwinner platforms.
Allwinner V3s scale down chip has not SRAM_C1 but only small SRAM_C (44kB).

Result of additional testing:

SRAM_C is mapped in two regions 0x0000_4000 (primary location,
by Datasheet) (size is 0xb000, probably exact size is 0xb0c0
and it is mapped to 4k boundary (to 0x0000_ffff))
and to 0x01d0_4000 (traditional SRAM_C1 region from 0x01d0_0000).

Rest of 0x01d0_0000 are discontinuously filled with R/W register sets
(probably some internals registers from VE) that I thought to be SRAM too.

Programming register SRAM_CTRL_REG0 (0x01c00_0000) with value 0x7fff_ffff
switch out whole region 0x01d0_0000-0x01df_ffff and 0x0000_4000-0x0000_ffff
(dedicate access to VE).

VE/cedrus code use this SRAM region indirectly
(VE_AVC_SRAM_PORT_OFFSET/VE_AVC_SRAM_PORT_DATA...)
and it is not influenced by "real" SRAM mapping or size
so it is working even without this patch.

Signed-off-by: Martin Cerveny <m.cerv...@computer.org>
---
 arch/arm/boot/dts/sun8i-v3s.dtsi | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/sun8i-v3s.dtsi b/arch/arm/boot/dts/sun8i-v3s.dtsi
index e8f304125e2d..bc4b4a0200cb 100644
--- a/arch/arm/boot/dts/sun8i-v3s.dtsi
+++ b/arch/arm/boot/dts/sun8i-v3s.dtsi
@@ -162,17 +162,17 @@ syscon: system-control@1c00000 {
                        #size-cells = <1>;
                        ranges;
 
-                       sram_c: sram@1d00000 {
+                       sram_c: sram@4000 {
                                compatible = "mmio-sram";
-                               reg = <0x01d00000 0x80000>;
+                               reg = <0x4000 0xb000>;
                                #address-cells = <1>;
                                #size-cells = <1>;
-                               ranges = <0 0x01d00000 0x80000>;
+                               ranges = <0 0x4000 0xb000>;
 
                                ve_sram: sram-section@0 {
                                        compatible = 
"allwinner,sun8i-v3s-sram-c1",
                                                     
"allwinner,sun4i-a10-sram-c1";
-                                       reg = <0x000000 0x80000>;
+                                       reg = <0x0 0xb000>;
                                };
                        };
                };
-- 
2.25.1

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