Commit-ID: cf878e169d37b596de41322291523951540984c1 Gitweb: https://git.kernel.org/tip/cf878e169d37b596de41322291523951540984c1 Author: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> AuthorDate: Mon, 27 Nov 2017 09:11:53 +0100 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitDate: Sun, 14 Jan 2018 21:11:57 +0100 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 <jan.kiszka@xxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: jailhouse-dev@xxxxxxxxxxxxxxxx Link: https://lkml.kernel.org/r/90d942dda9d48a8046e00bb3c1bb6757c83227be.1511770314.git.jan.kiszka@xxxxxxxxxxx --- arch/x86/kernel/jailhouse.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/arch/x86/kernel/jailhouse.c b/arch/x86/kernel/jailhouse.c index 2b55672..01d5b06 100644 --- a/arch/x86/kernel/jailhouse.c +++ b/arch/x86/kernel/jailhouse.c @@ -15,6 +15,7 @@ #include <asm/cpu.h> #include <asm/hypervisor.h> #include <asm/i8259.h> +#include <asm/irqdomain.h> #include <asm/reboot.h> #include <asm/setup.h> @@ -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) -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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