From patchwork Fri Feb 10 10:02:21 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [v3,3/3] KVM: PPC: epapr: install ev_idle hcall for e500 guest Date: Fri, 10 Feb 2012 00:02:21 -0000 From: Liu Yu-B13201 X-Patchwork-Id: 140540 Message-Id: <1328868141-17364-3-git-send-email-yu.liu@freescale.com> To: , , Cc: , , Liu Yu If the guest hypervisor node contains "has-idle" property. Signed-off-by: Liu Yu --- v3: 1. apply the hcall idle for all ppc platform 2. add a loop to prevent spurious wakeups arch/powerpc/kernel/Makefile | 2 +- arch/powerpc/kernel/epapr.S | 47 ++++++++++++++++++++++++++++++++++++++ arch/powerpc/kernel/epapr_para.c | 14 ++++++++++- 3 files changed, 61 insertions(+), 2 deletions(-) create mode 100644 arch/powerpc/kernel/epapr.S diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile index 1e41c76..65e24be 100644 --- a/arch/powerpc/kernel/Makefile +++ b/arch/powerpc/kernel/Makefile @@ -134,7 +134,7 @@ ifneq ($(CONFIG_XMON)$(CONFIG_KEXEC),) obj-y += ppc_save_regs.o endif -obj-$(CONFIG_EPAPR_PARA) += epapr_para.o +obj-$(CONFIG_EPAPR_PARA) += epapr_para.o epapr.o obj-$(CONFIG_KVM_GUEST) += kvm.o kvm_emul.o # Disable GCOV in odd or sensitive code diff --git a/arch/powerpc/kernel/epapr.S b/arch/powerpc/kernel/epapr.S new file mode 100644 index 0000000..34cc54f --- /dev/null +++ b/arch/powerpc/kernel/epapr.S @@ -0,0 +1,47 @@ +/* + * Copyright (C) 2012 Freescale Semiconductor, Inc. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define HC_VENDOR_EPAPR (1 << 16) +#define HC_EV_IDLE 16 + +_GLOBAL(epapr_ev_idle) +epapr_ev_idle: +#ifdef CONFIG_E500 + rlwinm r3,r1,0,0,31-THREAD_SHIFT /* current thread_info */ + lwz r4,TI_LOCAL_FLAGS(r3) /* set napping bit */ + ori r4,r4,_TLF_NAPPING /* so when we take an exception */ + stw r4,TI_LOCAL_FLAGS(r3) /* it will return to our caller */ +#endif + wrteei 1 + +idle_loop: + LOAD_REG_IMMEDIATE(r11, HC_VENDOR_EPAPR | HC_EV_IDLE) + +/* Hypercall entry point. Will be patched with device tree instructions. */ +.global epapr_hypercall_start +epapr_hypercall_start: + li r3, -1 + nop + nop + nop + + /* + * Guard against spurious wakeups (e.g. from a hypervisor) -- + * any real interrupt will cause us to return to LR due to + * _TLF_NAPPING. + */ + b idle_loop diff --git a/arch/powerpc/kernel/epapr_para.c b/arch/powerpc/kernel/epapr_para.c index 7e1561a..ff8fb78 100644 --- a/arch/powerpc/kernel/epapr_para.c +++ b/arch/powerpc/kernel/epapr_para.c @@ -20,6 +20,10 @@ #include #include #include +#include + +extern void epapr_ev_idle(void); +extern u32 epapr_hypercall_start[]; u32 *epapr_hcall_insts; int epapr_hcall_insts_len; @@ -28,7 +32,7 @@ static int __init epapr_para_init(void) { struct device_node *hyper_node; u32 *insts; - int len; + int len, i; hyper_node = of_find_node_by_path("/hypervisor"); if (!hyper_node) @@ -38,8 +42,16 @@ static int __init epapr_para_init(void) if (!(len % 4) && (len >= (4 * 4))) { epapr_hcall_insts = insts; epapr_hcall_insts_len = len; + + for (i = 0; i < (len / 4); i++) + epapr_hypercall_start[i] = insts[i]; + flush_icache_range((ulong)epapr_hypercall_start, + (ulong)epapr_hypercall_start + len); } + if (of_get_property(hyper_node, "has-idle", NULL)) + ppc_md.power_save = epapr_ev_idle; + return 0; }