video: vesa: Use mtrr_set_next_var() for graphics memory
At present this uses mtrr_add_request() & mtrr_commit() combination to program the MTRR for graphics memory. This usage has two major issues as below: - mtrr_commit() will re-initialize all MTRR registers from index 0, using the settings previously added by mtrr_add_request() and saved in gd->arch.mtrr_req[], which won't cause any issue but is unnecessary - The way such combination works is based on the assumption that U-Boot has full control with MTRR programming (e.g.: U-Boot without any blob that does all low-level initialization on its own, or using FSP2 which does not touch MTRR), but this is not the case with FSP. FSP programs some MTRRs during its execution but U-Boot does not have the settings saved in gd->arch.mtrr_req[] and when doing mtrr_commit() it will corrupt what was already programmed previously. Correct this to use mtrr_set_next_var() instead. Signed-off-by:Bin Meng <bmeng.cn@gmail.com> Reviewed-by:
Simon Glass <sjg@chromium.org>
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