• Paul Burton's avatar
    MIPS: GIC: Introduce asm/mips-gic.h with accessor functions · 582e2b4a
    Paul Burton authored
    This patch introduces a new header providing accessor functions for the
    MIPS Global Interrupt Controller (GIC) mirroring those provided for the
    other 2 components of the MIPS Coherent Processing System (CPS) - the
    Coherence Manager (CM) & Cluster Power Controller (CPC).
    
    This header makes use of the new standardised CPS accessor macros where
    possible, but does require some custom accessors for cases where we have
    either a bit or a register per interrupt.
    
    A major advantage of this over the existing
    include/linux/irqchip/mips-gic.h definitions is that code performing
    accesses can become much simpler, for example this:
    
      gic_update_bits(GIC_REG(SHARED, GIC_SH_SET_TRIGGER) +
                      GIC_INTR_OFS(intr), 1ul << GIC_INTR_BIT(intr),
                      (unsigned long)trig << GIC_INTR_BIT(intr));
    
    ...can become simply:
    
      change_gic_trig(intr, trig);
    
    The accessors handle 32 vs 64 bit in the same way as for CM & CPC code,
    which means that GIC code will also not need to worry about the access
    size in most cases. They are also accessible outside of
    drivers/irqchip/irq-mips-gic.c which will allow for simplification in
    the use of the non-interrupt portions of the GIC (eg. counters) which
    currently require the interrupt controller driver to expose helper
    functions for access.
    
    This patch doesn't change any existing code over to use the new
    accessors yet, since a wholesale change would be invasive & difficult to
    review. Instead follow-on patches will convert code piecemeal to use
    this new header. The one change to existing code is to rename gic_base
    to mips_gic_base & make it global, in order to fit in with the naming
    expected by the standardised CPS accessor macros.
    Signed-off-by: default avatarPaul Burton <paul.burton@imgtec.com>
    Acked-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
    Cc: Jason Cooper <jason@lakedaemon.net>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: linux-kernel@vger.kernel.org
    Cc: linux-mips@linux-mips.org
    Patchwork: https://patchwork.linux-mips.org/patch/17020/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
    582e2b4a
mips-gic.h 9.77 KB