Whether it's a tile based GPU or not doesn't really affect the texture cache architecture. The memory layout of texture will look like some flavor of Morton order or Hilbert curve in all GPUs.
As a result, it's more efficient to render triangles that are close to equilateral triangles because GPU memory system fetches cache lines of texels.
So obviously on tile borders, it may happen that you have to fetch texels twice. This has a small cost as tile borders are only "few" pixels.
Arguably desktop GPUs behave identically to tile based GPUs as experiments such as the following demonstrate:
http://www.g-truc.net/post-0597.html
The size of the tiles differ but both architecture actually process fragments into a hierarchy of tiles of different sizes.
When coding for tile based GPUs my recommendation is to always have in mind:
- Don't switch framebuffer objects unless you really need to.
- When binding a new framebuffer object, if you don't need to save the content of the current framebuffer, discard it. If don't want to load content of the new framebuffer, then you should clear the framebuffer.