From 47566421f029b0a489b63f8195b3ff944e017056 Mon Sep 17 00:00:00 2001 From: Alistair Francis Date: Wed, 12 Oct 2022 11:14:49 +1000 Subject: target/riscv: pmp: Fixup TLB size calculation Since commit 4047368938f6 "accel/tcg: Introduce tlb_set_page_full" we have been seeing this assert ../accel/tcg/cputlb.c:1294: tlb_set_page_with_attrs: Assertion `is_power_of_2(size)' failed. When running Tock on the OpenTitan machine. The issue is that pmp_get_tlb_size() would return a TLB size that wasn't a power of 2. The size was also smaller then TARGET_PAGE_SIZE. This patch ensures that any TLB size less then TARGET_PAGE_SIZE is rounded down to 1 to ensure it's a valid size. Signed-off-by: Alistair Francis Reviewed-by: LIU Zhiwei Reviewed-by: Richard Henderson Message-id: 20221012011449.506928-1-alistair.francis@opensource.wdc.com Message-Id: <20221012011449.506928-1-alistair.francis@opensource.wdc.com> --- target/riscv/pmp.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/target/riscv/pmp.c b/target/riscv/pmp.c index ea2b67d947..2b43e399b8 100644 --- a/target/riscv/pmp.c +++ b/target/riscv/pmp.c @@ -628,6 +628,18 @@ bool pmp_is_range_in_tlb(CPURISCVState *env, hwaddr tlb_sa, } if (*tlb_size != 0) { + /* + * At this point we have a tlb_size that is the smallest possible size + * That fits within a TARGET_PAGE_SIZE and the PMP region. + * + * If the size is less then TARGET_PAGE_SIZE we drop the size to 1. + * This means the result isn't cached in the TLB and is only used for + * a single translation. + */ + if (*tlb_size < TARGET_PAGE_SIZE) { + *tlb_size = 1; + } + return true; } -- cgit v1.2.3