Hi all, MIPS Uboot works OK.Part of the code is as below.
And my questions: 1.read status register($12) and save value to $10,but don't use the value in $10 to do anything. Because uboot overwrite $10. 2.Is it right?I can delete this code "mfc0 $10,$12" from uboot. Thanks. Bruce # Initialize Misc. Cop0 state # Read status register mfc0 $10, $12 //Can I delete this code? # Set up Status register: # Disable Coprocessor Usable bits # Turn off Reduce Power bit # Turn off reverse endian # Turn off BEV (use normal exception vectors) # Clear TS, SR, NMI bits # Clear Interrupt masks # Clear User Mode # Clear ERL # Set EXL # Clear Interrupt Enable # modify by Bruce #li $11, 0x0000ff02 li $11, 0x00000004 mtc0 $11, $12 # Disable watch exceptions mtc0 $0, $18 # Clear Watch Status bits li $11, 0x3 mtc0 $11, $19 # Clear WP bit to avoid watch exception upon user code entry # Clear IV bit - Interrupts go to general exception vector # Clear software interrupts mtc0 $0, $13 # Set KSeg0 to cacheable # Config.K0 mfc0 $10, $16 //Overwrite $10 register.Why uboot read status register($12) and save value to $10,but don't use $10. li $11, 0x7 not $11 and $10, $11 or $10, 0x3 mtc0 $10, $16
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