xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep

Provide the registration callback to call in the Xen's
ACPI sleep functionality. This means that during S3/S5
we make a hypercall XENPF_enter_acpi_sleep with the
proper PM1A/PM1B registers.

Based of Ke Yu's <[e-mail]> initial idea.
[ From http://xenbits.xensource.com/linux-2.6.18-xen.hg
change c68699484a65 ]

[v1: Added Copyright and license]
[v2: Added check if PM1A/B the 16-bits MSB contain something. The spec
only uses 16-bits but might have more in future]
Signed-off-by: Liang Tang <[e-mail]>
Signed-off-by: Konrad Rzeszutek Wilk <[e-mail]>

arch/x86/xen/enlighten.c

···
 #include <xen/page.h>
 #include <xen/hvm.h>
 #include <xen/hvc-console.h>
+#include <xen/acpi.h>
 
 #include <asm/paravirt.h>
 #include <asm/apic.h>
···
 
 		/* Make sure ACS will be enabled */
 		pci_request_acs();
+
+		xen_acpi_sleep_register();
 	}
 		
 

drivers/xen/Makefile

···
 obj-$(CONFIG_XEN_PVHVM)			+= platform-pci.o
 obj-$(CONFIG_XEN_TMEM)			+= tmem.o
 obj-$(CONFIG_SWIOTLB_XEN)		+= swiotlb-xen.o
-obj-$(CONFIG_XEN_DOM0)			+= pci.o
+obj-$(CONFIG_XEN_DOM0)			+= pci.o acpi.o
 obj-$(CONFIG_XEN_PCIDEV_BACKEND)	+= xen-pciback/
 obj-$(CONFIG_XEN_PRIVCMD)		+= xen-privcmd.o
 obj-$(CONFIG_XEN_ACPI_PROCESSOR)	+= xen-acpi-processor.o

drivers/xen/acpi.c

···
+/******************************************************************************
+ * acpi.c
+ * acpi file for domain 0 kernel
+ *
+ * Copyright (c) 2011 Konrad Rzeszutek Wilk <[e-mail]>
+ * Copyright (c) 2011 Yu Ke [e-mail]
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <xen/acpi.h>
+#include <xen/interface/platform.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/hypervisor.h>
+
+int xen_acpi_notify_hypervisor_state(u8 sleep_state,
+				     u32 pm1a_cnt, u32 pm1b_cnt)
+{
+	struct xen_platform_op op = {
+		.cmd = XENPF_enter_acpi_sleep,
+		.interface_version = XENPF_INTERFACE_VERSION,
+		.u = {
+			.enter_acpi_sleep = {
+				.pm1a_cnt_val = (u16)pm1a_cnt,
+				.pm1b_cnt_val = (u16)pm1b_cnt,
+				.sleep_state = sleep_state,
+			},
+		},
+	};
+
+	if ((pm1a_cnt & 0xffff0000) || (pm1b_cnt & 0xffff0000)) {
+		WARN(1, "Using more than 16bits of PM1A/B 0x%x/0x%x!"
+		     "Email [e-mail]  Thank you.\n", \
+		     pm1a_cnt, pm1b_cnt);
+		return -1;
+	}
+
+	HYPERVISOR_dom0_op(&op);
+	return 1;
+}

include/xen/acpi.h

···
+/******************************************************************************
+ * acpi.h
+ * acpi file for domain 0 kernel
+ *
+ * Copyright (c) 2011 Konrad Rzeszutek Wilk <[e-mail]>
+ * Copyright (c) 2011 Yu Ke <[e-mail]>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef _XEN_ACPI_H
+#define _XEN_ACPI_H
+
+#include <linux/types.h>
+
+#ifdef CONFIG_XEN_DOM0
+#include <asm/xen/hypervisor.h>
+#include <xen/xen.h>
+#include <linux/acpi.h>
+
+int xen_acpi_notify_hypervisor_state(u8 sleep_state,
+				     u32 pm1a_cnt, u32 pm1b_cnd);
+
+static inline void xen_acpi_sleep_register(void)
+{
+	if (xen_initial_domain())
+		acpi_os_set_prepare_sleep(
+			&xen_acpi_notify_hypervisor_state);
+}
+#else
+static inline void xen_acpi_sleep_register(void)
+{
+}
+#endif
+
+#endif	/* _XEN_ACPI_H */