On Fri, Dec 2, 2022 at 8:28 AM Wilfred Mallawa <wilfred.mall...@wdc.com> wrote: > > On Thu, 2022-12-01 at 22:08 +0800, Bin Meng wrote: > > The pending register upper limit is currently set to > > plic->num_sources >> 3, which is wrong, e.g.: considering > > plic->num_sources is 7, the upper limit becomes 0 which fails > > the range check if reading the pending register at pending_base. > > > > Fixes: 1e24429e40df ("SiFive RISC-V PLIC Block") > > Signed-off-by: Bin Meng <bm...@tinylab.org> > > > > --- > > > > hw/intc/sifive_plic.c | 5 +++-- > > 1 file changed, 3 insertions(+), 2 deletions(-) > > > > diff --git a/hw/intc/sifive_plic.c b/hw/intc/sifive_plic.c > > index 7a6a358c57..a3fc8222c7 100644 > > --- a/hw/intc/sifive_plic.c > > +++ b/hw/intc/sifive_plic.c > > @@ -143,7 +143,8 @@ static uint64_t sifive_plic_read(void *opaque, > > hwaddr addr, unsigned size) > > uint32_t irq = (addr - plic->priority_base) >> 2; > > > > return plic->source_priority[irq]; > > - } else if (addr_between(addr, plic->pending_base, plic- > > >num_sources >> 3)) { > > + } else if (addr_between(addr, plic->pending_base, > > + (plic->num_sources + 31) >> 3)) { > why does adding specifically 31 work here? >
Each pending register is 32-bit for 32 interrupt sources. Adding 31 is to round up to next pending register offset. Regards, Bin