soc: qcom: hvc: add hypervisor call support

Add API support for calling into the hypervisor. This will allow
various drivers to avail hypervisor services.

Change-Id: I0a0e8f8fe13a550ad20c5421b712e207933c82f3
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
[pdaly@codeaurora.org Resolve minor conflicts]
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>

drivers/soc/qcom/Kconfig

@@ -179,6 +179,15 @@ config QCOM_SMEM
 	  The driver provides an interface to items in a heap shared among all
 	  processors in a Qualcomm platform.
 
+config MSM_HVC
+	bool "MSM Hypervisor Call Support"
+	help
+	  This enables the Hypervisor Call module. It provides apis to call
+	  into the hypervisor thereby allowing access to services exposed by
+	  the hypervisor. It is primarily intended to be used for Silicon
+	  Partner/Manufacturer function identifier subrange but supports other
+	  service call subranges as well.
+
 config MSM_IPC_ROUTER_SMD_XPRT
 	depends on MSM_SMD
 	depends on IPC_ROUTER

drivers/soc/qcom/Makefile

@@ -13,6 +13,7 @@ obj-$(CONFIG_MSM_SMP2P)	+=	smp2p.o smp2p_debug.o smp2p_sleepstate.o
 obj-$(CONFIG_MSM_SMP2P_TEST)	+=	smp2p_loopback.o smp2p_test.o smp2p_spinlock_test.o
 obj-$(CONFIG_MSM_QMI_INTERFACE)	+=	qmi_interface.o
 obj-$(CONFIG_MSM_RPM_SMD)	+=	rpm-smd.o
+obj-$(CONFIG_MSM_HVC) += hvc.o
 ifdef CONFIG_DEBUG_FS
 obj-$(CONFIG_MSM_RPM_SMD)	+=	rpm-smd-debug.o
 endif

drivers/soc/qcom/hvc.c

@@ -0,0 +1,102 @@
+/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/io.h>
+#include <linux/export.h>
+#include <linux/err.h>
+
+#include <asm/compiler.h>
+
+#include <soc/qcom/hvc.h>
+
+#define HVC_RET_SUCCESS				0
+#define HVC_RET_ERROR				-1
+#define HVC_RET_EFUNCNOSUPPORT			-2
+#define HVC_RET_EINVALARCH			-3
+#define HVC_RET_EMEMMAP				-4
+#define HVC_RET_EMEMUNMAP			-5
+#define HVC_RET_EMEMPERM			-6
+
+static int hvc_to_linux_errno(int errno)
+{
+	switch (errno) {
+	case HVC_RET_SUCCESS:
+		return 0;
+	case HVC_RET_ERROR:
+		return -EIO;
+	case HVC_RET_EFUNCNOSUPPORT:
+		return -EOPNOTSUPP;
+	case HVC_RET_EINVALARCH:
+	case HVC_RET_EMEMMAP:
+	case HVC_RET_EMEMUNMAP:
+		return -EINVAL;
+	case HVC_RET_EMEMPERM:
+		return -EPERM;
+	};
+
+	return -EINVAL;
+}
+
+#ifdef CONFIG_ARM64
+static int __hvc(u64 x0, u64 x1, u64 x2, u64 x3, u64 x4, u64 x5,
+		 u64 x6, u64 x7, u64 *ret1, u64 *ret2, u64 *ret3)
+{
+	register u64 r0 asm("x0") = x0;
+	register u64 r1 asm("x1") = x1;
+	register u64 r2 asm("x2") = x2;
+	register u64 r3 asm("x3") = x3;
+	register u64 r4 asm("x4") = x4;
+	register u64 r5 asm("x5") = x5;
+	register u64 r6 asm("x6") = x6;
+	register u64 r7 asm("x7") = x7;
+
+	asm volatile(
+			__asmeq("%0", "x0")
+			__asmeq("%1", "x1")
+			__asmeq("%2", "x2")
+			__asmeq("%3", "x3")
+			__asmeq("%4", "x4")
+			__asmeq("%5", "x5")
+			__asmeq("%6", "x6")
+			__asmeq("%7", "x7")
+			"hvc	#0\n"
+		: "+r" (r0), "+r" (r1), "+r" (r2), "+r" (r3)
+		: "r" (r4), "r" (r5), "r" (r6), "r" (r7));
+
+	*ret1 = r1;
+	*ret2 = r2;
+	*ret3 = r3;
+
+	return r0;
+}
+#else
+static int __hvc(u64 x0, u64 x1, u64 x2, u64 x3, u64 x4, u64 x5,
+		 u64 x6, u64 *ret1, u64 *ret2, u64 *ret3)
+{
+	return 0;
+}
+#endif
+
+int hvc(u64 func_id, struct hvc_desc *desc)
+{
+	int ret;
+
+	if (!desc)
+		return -EINVAL;
+
+	ret = __hvc(func_id, desc->arg[0], desc->arg[1], desc->arg[2],
+		    desc->arg[3], desc->arg[4], desc->arg[5], 0,
+		    &desc->ret[0], &desc->ret[1], &desc->ret[2]);
+
+	return hvc_to_linux_errno(ret);
+}
+EXPORT_SYMBOL(hvc);

include/soc/qcom/hvc.h

@@ -0,0 +1,58 @@
+/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MSM_HVC_H
+#define __MSM_HVC_H
+
+#ifdef CONFIG_ARM64
+#define HVC_FN_ARM_BASE				0xC0000000
+#define HVC_FN_CPU_BASE				0xC1000000
+#define HVC_FN_SIP_BASE				0xC2000000
+#define HVC_FN_OEM_BASE				0xC3000000
+#define HVC_FN_APP_BASE				0xF0000000
+#define HVC_FN_OS_BASE				0xF2000000
+#else
+#define HVC_FN_ARM_BASE				0x80000000
+#define HVC_FN_CPU_BASE				0x81000000
+#define HVC_FN_SIP_BASE				0x82000000
+#define HVC_FN_OEM_BASE				0x83000000
+#define HVC_FN_APP_BASE				0xB0000000
+#define HVC_FN_OS_BASE				0xB2000000
+#endif
+
+#define HVC_FN_ARM(n)				(HVC_FN_ARM_BASE + (n))
+#define HVC_FN_CPU(n)				(HVC_FN_CPU_BASE + (n))
+#define HVC_FN_SIP(n)				(HVC_FN_SIP_BASE + (n))
+#define HVC_FN_OEM(n)				(HVC_FN_OEM_BASE + (n))
+#define HVC_FN_APP(n)				(HVC_FN_APP_BASE + (n))
+#define HVC_FN_OS(n)				(HVC_FN_OS_BASE + (n))
+
+#define HVC_MAX_ARGS				6
+#define HVC_MAX_RETS				3
+#define HVC_MAX_EXTRA_ARGS			4
+
+struct hvc_desc {
+	u64 arg[HVC_MAX_ARGS];
+	u64 ret[HVC_MAX_RETS];
+};
+
+struct hvc_extra_args {
+	u64 arg[HVC_MAX_EXTRA_ARGS];
+};
+
+#ifdef CONFIG_MSM_HVC
+extern int hvc(u64 func_id, struct hvc_desc *desc);
+#else
+static inline int hvc(u64 func_id, struct hvc_desc *desc) { return 0; }
+#endif
+
+#endif