Section 5 Exceptions
SH7751 Group, SH7751R Group
Page 154 of 1128
R01UH0457EJ0301 Rev. 3.01
Sep 24, 2013
(3) Initial Page Write Exception
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Source: TLB is hit in a store access, but dirty bit D = 0
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Transition address: VBR + H'0000 0100
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Transition operations:
The virtual address (32 bits) at which this exception occurred is set in TEA, and the
corresponding virtual page number (22 bits) is set in PTEH [31:10]. ASID in PTEH indicates
the ASID when this exception occurred.
The PC and SR contents for the instruction at which this exception occurred are saved in SPC
and SSR. The R15 contents at this time are saved in SGR.
Exception code H'080 is set in EXPEVT. The BL, MD, and RB bits are set to 1 in SR, and a
branch is made to PC = VBR + H'0100.
Initial_write_exception()
{
TEA = EXCEPTION_ADDRESS;
PTEH.VPN = PAGE_NUMBER;
SPC = PC;
SSR = SR;
SGR = R15;
EXPEVT = H'00000080;
SR.MD = 1;
SR.RB = 1;
SR.BL = 1;
PC = VBR + H'00000100;
}