From ef3548668c02cc8c3922f4423f32b53e662811c6 Mon Sep 17 00:00:00 2001 From: Jacob Pan Date: Mon, 9 Nov 2009 11:24:14 -0800 Subject: x86, pic: Introduce legacy_pic abstraction This patch makes i8259A like legacy programmable interrupt controller code into a driver so that legacy pic functions can be selected at runtime based on platform information, such as HW subarchitecure ID. Default structure of legacy_pic maintains the current code path for x86pc. Signed-off-by: Jacob Pan LKML-Reference: <43F901BD926A4E43B106BF17856F07559FB80D03@orsmsx508.amr.corp.intel.com> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/i8259.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'arch/x86/kernel/i8259.c') diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c index df89102bef80..b80987ca33ea 100644 --- a/arch/x86/kernel/i8259.c +++ b/arch/x86/kernel/i8259.c @@ -358,3 +358,46 @@ void init_8259A(int auto_eoi) spin_unlock_irqrestore(&i8259A_lock, flags); } +/* + * make i8259 a driver so that we can select pic functions at run time. the goal + * is to make x86 binary compatible among pc compatible and non-pc compatible + * platforms, such as x86 MID. + */ + +static void __init legacy_pic_noop(void) { }; +static void __init legacy_pic_uint_noop(unsigned int unused) { }; +static void __init legacy_pic_int_noop(int unused) { }; + +static struct irq_chip dummy_pic_chip = { + .name = "dummy pic", + .mask = legacy_pic_uint_noop, + .unmask = legacy_pic_uint_noop, + .disable = legacy_pic_uint_noop, + .mask_ack = legacy_pic_uint_noop, +}; +static int legacy_pic_irq_pending_noop(unsigned int irq) +{ + return 0; +} + +struct legacy_pic null_legacy_pic = { + .nr_legacy_irqs = 0, + .chip = &dummy_pic_chip, + .mask_all = legacy_pic_noop, + .restore_mask = legacy_pic_noop, + .init = legacy_pic_int_noop, + .irq_pending = legacy_pic_irq_pending_noop, + .make_irq = legacy_pic_uint_noop, +}; + +struct legacy_pic default_legacy_pic = { + .nr_legacy_irqs = NR_IRQS_LEGACY, + .chip = &i8259A_chip, + .mask_all = mask_8259A, + .restore_mask = unmask_8259A, + .init = init_8259A, + .irq_pending = i8259A_irq_pending, + .make_irq = make_8259A_irq, +}; + +struct legacy_pic *legacy_pic = &default_legacy_pic; -- cgit v1.2.3