forked from Minki/linux
f725758b89
POWER9 includes a new interrupt controller, called XIVE, which is quite different from the XICS interrupt controller on POWER7 and POWER8 machines. KVM-HV accesses the XICS directly in several places in order to send and clear IPIs and handle interrupts from PCI devices being passed through to the guest. In order to make the transition to XIVE easier, OPAL firmware will include an emulation of XICS on top of XIVE. Access to the emulated XICS is via OPAL calls. The one complication is that the EOI (end-of-interrupt) function can now return a value indicating that another interrupt is pending; in this case, the XIVE will not signal an interrupt in hardware to the CPU, and software is supposed to acknowledge the new interrupt without waiting for another interrupt to be delivered in hardware. This adapts KVM-HV to use the OPAL calls on machines where there is no XICS hardware. When there is no XICS, we look for a device-tree node with "ibm,opal-intc" in its compatible property, which is how OPAL indicates that it provides XICS emulation. In order to handle the EOI return value, kvmppc_read_intr() has become kvmppc_read_one_intr(), with a boolean variable passed by reference which can be set by the EOI functions to indicate that another interrupt is pending. The new kvmppc_read_intr() keeps calling kvmppc_read_one_intr() until there are no more interrupts to process. The return value from kvmppc_read_intr() is the largest non-zero value of the returns from kvmppc_read_one_intr(). Signed-off-by: Paul Mackerras <paulus@ozlabs.org> |
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| .. | ||
| boot | ||
| configs | ||
| crypto | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| perf | ||
| platforms | ||
| scripts | ||
| sysdev | ||
| xmon | ||
| Kconfig | ||
| Kconfig.debug | ||
| Makefile | ||
| relocs_check.sh | ||