From cf878e169d37b596de41322291523951540984c1 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Mon, 27 Nov 2017 09:11:53 +0100 Subject: x86/jailhouse: Wire up IOAPIC for legacy UART ports The typical I/O interrupts in non-root cells are MSI-based. However, the platform UARTs do not support MSI. In order to run a non-root cell that shall use one of them, the standard IOAPIC must be registered and 1:1 routing for IRQ 3 and 4 set up. If an IOAPIC is not available, the boot loader clears standard_ioapic in the setup data, so registration is skipped. If the guest is not allowed to to use one of those pins, Jailhouse will simply ignore the access. Signed-off-by: Jan Kiszka Signed-off-by: Thomas Gleixner Cc: jailhouse-dev@googlegroups.com Link: https://lkml.kernel.org/r/90d942dda9d48a8046e00bb3c1bb6757c83227be.1511770314.git.jan.kiszka@siemens.com --- arch/x86/kernel/jailhouse.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'arch/x86/kernel/jailhouse.c') diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c index 2b55672ca05f..01d5b06a42bc 100644 --- a/arch/x86/kernel/jailhouse.c +++ b/arch/x86/kernel/jailhouse.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include @@ -52,6 +53,15 @@ static unsigned long jailhouse_get_tsc(void) static void __init jailhouse_get_smp_config(unsigned int early) { + struct ioapic_domain_cfg ioapic_cfg = { + .type = IOAPIC_DOMAIN_STRICT, + .ops = &mp_ioapic_irqdomain_ops, + }; + struct mpc_intsrc mp_irq = { + .type = MP_INTSRC, + .irqtype = mp_INT, + .irqflag = MP_IRQPOL_ACTIVE_HIGH | MP_IRQTRIG_EDGE, + }; unsigned int cpu; if (x2apic_enabled()) { @@ -77,6 +87,17 @@ static void __init jailhouse_get_smp_config(unsigned int early) } smp_found_config = 1; + + if (setup_data.standard_ioapic) { + mp_register_ioapic(0, 0xfec00000, gsi_top, &ioapic_cfg); + + /* Register 1:1 mapping for legacy UART IRQs 3 and 4 */ + mp_irq.srcbusirq = mp_irq.dstirq = 3; + mp_save_irq(&mp_irq); + + mp_irq.srcbusirq = mp_irq.dstirq = 4; + mp_save_irq(&mp_irq); + } } static void jailhouse_no_restart(void) -- cgit v1.2.3-59-g8ed1b