qemu-e2k/include/hw/intc/ibex_plic.h
Alistair Francis deef3d2568 intc/ibex_plic: Ensure we don't loose interrupts
If an interrupt occurs between when we claim and complete an interrupt
we currently drop the interrupt in ibex_plic_irqs_set_pending(). This
somewhat matches hardware that also ignore the interrupt between the
claim and complete process.

In the case of hardware though the physical interrupt line will still
be asserted after we have completed the interrupt. This means we will
still act on the interrupt after the complete process. In QEMU we don't
and instead we drop the interrupt as it is never recorded.

This patch changed the behaviour of the Ibex PLIC so that we save all
interrupts that occur while we are between claiming and completing an
interrupt so that we can act on them after the completition process.

This fixes interrupts being dropped when running Tock on OpenTitain in
QEMU.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: e7bcf98c6925b1e6e7828e7c3f85293a09a65b12.1605136387.git.alistair.francis@wdc.com
2020-11-13 21:43:48 -08:00

66 lines
1.5 KiB
C

/*
* QEMU RISC-V lowRISC Ibex PLIC
*
* Copyright (c) 2020 Western Digital
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2 or later, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef HW_IBEX_PLIC_H
#define HW_IBEX_PLIC_H
#include "hw/sysbus.h"
#include "qom/object.h"
#define TYPE_IBEX_PLIC "ibex-plic"
OBJECT_DECLARE_SIMPLE_TYPE(IbexPlicState, IBEX_PLIC)
struct IbexPlicState {
/*< private >*/
SysBusDevice parent_obj;
/*< public >*/
MemoryRegion mmio;
uint32_t *pending;
uint32_t *hidden_pending;
uint32_t *claimed;
uint32_t *source;
uint32_t *priority;
uint32_t *enable;
uint32_t threshold;
uint32_t claim;
/* config */
uint32_t num_cpus;
uint32_t num_sources;
uint32_t pending_base;
uint32_t pending_num;
uint32_t source_base;
uint32_t source_num;
uint32_t priority_base;
uint32_t priority_num;
uint32_t enable_base;
uint32_t enable_num;
uint32_t threshold_base;
uint32_t claim_base;
};
#endif /* HW_IBEX_PLIC_H */