[v5,0/5] IRQ affinity support in PLIC driver

Message

Anup Patel Jan. 19, 2019, 5:56 a.m. UTC

This patchset primarily adds IRQ affinity support in PLIC driver and
other improvements.

It gives mechanism for explicitly route external interrupts to particular
CPUs using smp_affinity attribute of each Linux IRQs. Also, we can now
use IRQ balancer from kernel-space or user-space.

The patchset is tested on QEMU virt machine. It is based on Linux-4.20
and can be found at riscv_plic_irq_affinity_v4 branch of:
https://github.com/avpatel/linux.git

Changes since v4:
 - Use "if (force)" instead of "if (!force)" in PATCH5

Changes since v3:
 - Dropped PATCH2
 - Added PATCH to not inline plic_toggle() and plic_irq_toggle()
 - Moved PATCH3 changes to PATCH6
 - Used WARN_ON_ONCE() instead of WARN_ON() in PATCH5

Changes since v2:
 - Fixed incorrect address of enable registers using sizeof(u32) in PATCH1
 - Retained comment about need for locking in PATCH1
 - Split PATCH2 into two patches
 - Split PATCH3 into two patches
 - Minor fix in commit description of PATCH4

Changes since v1:
 - Removed few whitspace changes from PATCH1
 - Keep use of DEFINE_PER_CPU() as it is

Anup Patel (5):
  irqchip: sifive-plic: Pre-compute context hart base and enable base
  irqchip: sifive-plic: Don't inline plic_toggle() and plic_irq_toggle()
  irqchip: sifive-plic: Add warning in plic_init() if handler already
    present
  irqchip: sifive-plic: Differentiate between PLIC handler and context
  irqchip: sifive-plic: Implement irq_set_affinity() for SMP host

 drivers/irqchip/irq-sifive-plic.c | 110 +++++++++++++++++++-----------
 1 file changed, 71 insertions(+), 39 deletions(-)