target/riscv/pmp.c: Fix pmp_decode_napot()

Currently, start and end address of a PMP region are not decoded
correctly by pmp_decode_napot().

Let's say we have a 128KB PMP region with base address as 0x80000000.
Now, the PMPADDRx CSR value for this region will be 0x20003fff.

The current pmp_decode_napot() implementation will decode PMPADDRx
CSR as t1=14, base=0x100000000, and range=0x1ffff whereas it should
have decoded PMPADDRx CSR as t1=14, base=0x80000000, and range=0x1fff.

This patch fixes the base value decoding in pmp_decode_napot() when
PMPADDRx CSR is not -1 (i.e. 0xffffffffffffffff).

Signed-off-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
This commit is contained in:
Anup Patel 2018-12-14 19:12:32 +00:00 committed by Palmer Dabbelt
parent 40061ac0bc
commit 71a150bc91
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@ -138,7 +138,7 @@ static void pmp_decode_napot(target_ulong a, target_ulong *sa, target_ulong *ea)
return; return;
} else { } else {
target_ulong t1 = ctz64(~a); target_ulong t1 = ctz64(~a);
target_ulong base = (a & ~(((target_ulong)1 << t1) - 1)) << 3; target_ulong base = (a & ~(((target_ulong)1 << t1) - 1)) << 2;
target_ulong range = ((target_ulong)1 << (t1 + 3)) - 1; target_ulong range = ((target_ulong)1 << (t1 + 3)) - 1;
*sa = base; *sa = base;
*ea = base + range; *ea = base + range;