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Hello All,
I am using Omap3515 (Arm Cortex A8). Enabled I-Cache, D-Cache, Branch Prediction and MMU.
Issue 1:
But what I could notice is code region in external ram is executing faster than internal ram.
If I disable MMU, then access to internal ram is faster. It would be great, if someone explains this.
Issue 2:
And also I am getting a data abort, if I try to copy a frame buffer of 600KB from an external memory region to another external memory region.
Please find attached the MMU Page table
Thanks and regards,
Gopu
Good question... External ram faster than internal ? very strange... Really i have no idea about this. But may be somebody here could have an explaination ?Now my stupid question : Are you sure you use the external memory and not that of the GPU ?
I am using the SDRC, it is CS0 SDRAM. If MMU is enabled then internal ram access speed reduces.
After the data abort, I could notice that the SDR i.e SDRAM is not accessible.
Internal ram issue is due to a mistake in my code. It is solved now. But external ram still aborts. More details in the below link
ARM Cortex A8 : Enabling D Cache aborts