RT1052 sdram作为lcd显存问题

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

RT1052 sdram作为lcd显存问题

Jump to solution
4,656 Views
qq240997293
Contributor I

前提条件:
1.sdram的配置使用官方DCD配置,配置为166MHz;
2.lcd的显存地址为0x81800000,每帧大小为800*480*4 byte,目前项目用了5帧数据;
3.将0x81800000后的8MB空间配置为noncache,如下图

qq240997293_0-1652262492869.png

问题描述:
1.将帧①的数据拷贝到帧②,如下代码

qq240997293_1-1652262579512.png

花费时间过长,消耗了约112ms;
2.将帧③的数据全都写为0xFFFFFFFF,消耗了约24ms;

而将0x81800000后的8MB空间配置为cacheable,如下图

qq240997293_2-1652262755809.png

问题1的耗时时间变为28ms;
问题2的耗时时间基本不变。

但是将0x81800000后的8MB空间配置为cacheable的情况下,LCD显示出来的画面存在部分像素点不对的情况,而noncache的情况下,显示出来的画面都是对的。

提问:
请问
1.怎么保证拷贝帧①到帧②的耗时约30ms已内的情况下,使显示数据正确??
2.一般显存是需要配置为noncache的,但是我这拷贝一帧速率不满足要求,是啥具体原因导致的?
怎么解决?

 

 

0 Kudos
1 Solution
4,645 Views
jeremyzhou
NXP Employee
NXP Employee

Hi,

非常感谢使用NXP产品,很高兴为你提供技术支持!
1.怎么保证拷贝帧①到帧②的耗时约30ms已内的情况下,使显示数据正确??
-- 你可以试试DMA.
2.一般显存是需要配置为noncache的,但是我这拷贝一帧速率不满足要求,是啥具体原因导致的?
-- 应该跟Cache特性有关,建议参考此应用手册了解一下。

Have a great day,
TIC

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

 

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------

 

View solution in original post

0 Kudos
4 Replies
4,642 Views
qq240997293
Contributor I

已经试过DMA传输,结果速度更慢。
疑似是sdk版本不一致,导致clk配置不一致导致的。
我用同样的硬件,在别人的代码环境下面跑就速度就上去了。
别人使用了官方最新的sdk,我用的野火开发板的旧sdk。

0 Kudos
4,646 Views
jeremyzhou
NXP Employee
NXP Employee

Hi,

非常感谢使用NXP产品,很高兴为你提供技术支持!
1.怎么保证拷贝帧①到帧②的耗时约30ms已内的情况下,使显示数据正确??
-- 你可以试试DMA.
2.一般显存是需要配置为noncache的,但是我这拷贝一帧速率不满足要求,是啥具体原因导致的?
-- 应该跟Cache特性有关,建议参考此应用手册了解一下。

Have a great day,
TIC

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

 

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------

 

0 Kudos
4,634 Views
qq240997293
Contributor I

仍然未解决,我遇到的问题跟这个帖子很像;
(25条消息) rt1052 usb速率_RT1052 SDRAM内数据拷贝太慢_weixin_39733232的博客-CSDN博客
但是并没有人解答。
LCD显存部分应该是不允许开cache的,因为会导致花屏。
不知道我这sdram拷贝数据速度异常缓慢的原因是啥。

0 Kudos
4,614 Views
jeremyzhou
NXP Employee
NXP Employee

Hi,
感谢回复!
我建议你测试一下SDRAM的性能表现, 具体参考应用手册代码
Have a great day,
TIC

-------------------------------------------------------------------------------
Note:
- If this post answers your question, please click the "Mark Correct" button. Thank you!

 

- We are following threads for 7 weeks after the last post, later replies are ignored
Please open a new thread and refer to the closed one, if you have a related question at a later point in time.
-------------------------------------------------------------------------------

0 Kudos