[RFC PATCH 1/5] firmware: qcom: scm: Split out 32-bit specific SCM code

[Kumar Gala <galak@codeaurora.org>]

Split out the 32-bit SCM implementation into its own file to prep for
supporting a 64-bit/ARM64 implementation as well.  We create a simple shim
to ensure both versions conform to the same interface.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
---
 drivers/firmware/Makefile                      |   3 +-
 drivers/firmware/{qcom_scm.c => qcom_scm-32.c} |  15 +-
 drivers/firmware/qcom_scm.c                    | 442 +------------------------
 drivers/firmware/qcom_scm.h                    |  29 ++
 4 files changed, 42 insertions(+), 447 deletions(-)
 copy drivers/firmware/{qcom_scm.c => qcom_scm-32.c} (96%)
 create mode 100644 drivers/firmware/qcom_scm.h

diff --git a/drivers/firmware/Makefile b/drivers/firmware/Makefile
index 3fdd391..3001f1a 100644
--- a/drivers/firmware/Makefile
+++ b/drivers/firmware/Makefile
@@ -12,7 +12,8 @@ obj-$(CONFIG_ISCSI_IBFT_FIND)	+= iscsi_ibft_find.o
 obj-$(CONFIG_ISCSI_IBFT)	+= iscsi_ibft.o
 obj-$(CONFIG_FIRMWARE_MEMMAP)	+= memmap.o
 obj-$(CONFIG_QCOM_SCM)		+= qcom_scm.o
-CFLAGS_qcom_scm.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
+obj-$(CONFIG_QCOM_SCM)		+= qcom_scm-32.o
+CFLAGS_qcom_scm-32.o :=$(call as-instr,.arch_extension sec,-DREQUIRES_SEC=1)
 
 obj-$(CONFIG_GOOGLE_FIRMWARE)	+= google/
 obj-$(CONFIG_EFI)		+= efi/
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm-32.c
similarity index 96%
copy from drivers/firmware/qcom_scm.c
copy to drivers/firmware/qcom_scm-32.c
index 994b50f..89be15e 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm-32.c
@@ -27,6 +27,7 @@
 #include <asm/outercache.h>
 #include <asm/cacheflush.h>
 
+#include "qcom_scm.h"
 
 #define QCOM_SCM_ENOMEM		-5
 #define QCOM_SCM_EOPNOTSUPP	-4
@@ -386,8 +387,6 @@ u32 qcom_scm_get_version(void)
 }
 EXPORT_SYMBOL(qcom_scm_get_version);
 
-#define QCOM_SCM_SVC_BOOT			0x1
-#define QCOM_SCM_BOOT_ADDR			0x1
 /*
  * Set the cold/warm boot address for one of the CPU cores.
  */
@@ -412,7 +411,7 @@ static int qcom_scm_set_boot_addr(u32 addr, int flags)
  * Set the cold boot address of the cpus. Any cpu outside the supported
  * range would be removed from the cpu present mask.
  */
-int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
+int __qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 {
 	int flags = 0;
 	int cpu;
@@ -435,7 +434,6 @@ int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 
 	return qcom_scm_set_boot_addr(virt_to_phys(entry), flags);
 }
-EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
 
 /**
  * qcom_scm_set_warm_boot_addr() - Set the warm boot address for cpus
@@ -445,7 +443,7 @@ EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
  * Set the Linux entry point for the SCM to transfer control to when coming
  * out of a power down. CPU power down may be executed on cpuidle or hotplug.
  */
-int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
+int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 {
 	int ret;
 	int flags = 0;
@@ -473,10 +471,6 @@ int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 
 	return ret;
 }
-EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
-
-#define QCOM_SCM_CMD_TERMINATE_PC	0x2
-#define QCOM_SCM_FLUSH_FLAG_MASK	0x3
 
 /**
  * qcom_scm_cpu_power_down() - Power down the cpu
@@ -486,9 +480,8 @@ EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
  * the control would return from this function, otherwise, the cpu jumps to the
  * warm boot entry point set for this cpu upon reset.
  */
-void qcom_scm_cpu_power_down(u32 flags)
+void __qcom_scm_cpu_power_down(u32 flags)
 {
 	qcom_scm_call_atomic1(QCOM_SCM_SVC_BOOT, QCOM_SCM_CMD_TERMINATE_PC,
 			flags & QCOM_SCM_FLUSH_FLAG_MASK);
 }
-EXPORT_SYMBOL(qcom_scm_cpu_power_down);
diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 994b50f..9989241 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -16,393 +16,12 @@
  * 02110-1301, USA.
  */
 
-#include <linux/slab.h>
-#include <linux/io.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/errno.h>
-#include <linux/err.h>
+#include <linux/cpumask.h>
+#include <linux/export.h>
+#include <linux/types.h>
 #include <linux/qcom_scm.h>
 
-#include <asm/outercache.h>
-#include <asm/cacheflush.h>
-
-
-#define QCOM_SCM_ENOMEM		-5
-#define QCOM_SCM_EOPNOTSUPP	-4
-#define QCOM_SCM_EINVAL_ADDR	-3
-#define QCOM_SCM_EINVAL_ARG	-2
-#define QCOM_SCM_ERROR		-1
-#define QCOM_SCM_INTERRUPTED	1
-
-#define QCOM_SCM_FLAG_COLDBOOT_CPU0	0x00
-#define QCOM_SCM_FLAG_COLDBOOT_CPU1	0x01
-#define QCOM_SCM_FLAG_COLDBOOT_CPU2	0x08
-#define QCOM_SCM_FLAG_COLDBOOT_CPU3	0x20
-
-#define QCOM_SCM_FLAG_WARMBOOT_CPU0	0x04
-#define QCOM_SCM_FLAG_WARMBOOT_CPU1	0x02
-#define QCOM_SCM_FLAG_WARMBOOT_CPU2	0x10
-#define QCOM_SCM_FLAG_WARMBOOT_CPU3	0x40
-
-struct qcom_scm_entry {
-	int flag;
-	void *entry;
-};
-
-static struct qcom_scm_entry qcom_scm_wb[] = {
-	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU0 },
-	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU1 },
-	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU2 },
-	{ .flag = QCOM_SCM_FLAG_WARMBOOT_CPU3 },
-};
-
-static DEFINE_MUTEX(qcom_scm_lock);
-
-/**
- * struct qcom_scm_command - one SCM command buffer
- * @len: total available memory for command and response
- * @buf_offset: start of command buffer
- * @resp_hdr_offset: start of response buffer
- * @id: command to be executed
- * @buf: buffer returned from qcom_scm_get_command_buffer()
- *
- * An SCM command is laid out in memory as follows:
- *
- *	------------------- <--- struct qcom_scm_command
- *	| command header  |
- *	------------------- <--- qcom_scm_get_command_buffer()
- *	| command buffer  |
- *	------------------- <--- struct qcom_scm_response and
- *	| response header |      qcom_scm_command_to_response()
- *	------------------- <--- qcom_scm_get_response_buffer()
- *	| response buffer |
- *	-------------------
- *
- * There can be arbitrary padding between the headers and buffers so
- * you should always use the appropriate qcom_scm_get_*_buffer() routines
- * to access the buffers in a safe manner.
- */
-struct qcom_scm_command {
-	__le32 len;
-	__le32 buf_offset;
-	__le32 resp_hdr_offset;
-	__le32 id;
-	__le32 buf[0];
-};
-
-/**
- * struct qcom_scm_response - one SCM response buffer
- * @len: total available memory for response
- * @buf_offset: start of response data relative to start of qcom_scm_response
- * @is_complete: indicates if the command has finished processing
- */
-struct qcom_scm_response {
-	__le32 len;
-	__le32 buf_offset;
-	__le32 is_complete;
-};
-
-/**
- * alloc_qcom_scm_command() - Allocate an SCM command
- * @cmd_size: size of the command buffer
- * @resp_size: size of the response buffer
- *
- * Allocate an SCM command, including enough room for the command
- * and response headers as well as the command and response buffers.
- *
- * Returns a valid &qcom_scm_command on success or %NULL if the allocation fails.
- */
-static struct qcom_scm_command *alloc_qcom_scm_command(size_t cmd_size, size_t resp_size)
-{
-	struct qcom_scm_command *cmd;
-	size_t len = sizeof(*cmd) + sizeof(struct qcom_scm_response) + cmd_size +
-		resp_size;
-	u32 offset;
-
-	cmd = kzalloc(PAGE_ALIGN(len), GFP_KERNEL);
-	if (cmd) {
-		cmd->len = cpu_to_le32(len);
-		offset = offsetof(struct qcom_scm_command, buf);
-		cmd->buf_offset = cpu_to_le32(offset);
-		cmd->resp_hdr_offset = cpu_to_le32(offset + cmd_size);
-	}
-	return cmd;
-}
-
-/**
- * free_qcom_scm_command() - Free an SCM command
- * @cmd: command to free
- *
- * Free an SCM command.
- */
-static inline void free_qcom_scm_command(struct qcom_scm_command *cmd)
-{
-	kfree(cmd);
-}
-
-/**
- * qcom_scm_command_to_response() - Get a pointer to a qcom_scm_response
- * @cmd: command
- *
- * Returns a pointer to a response for a command.
- */
-static inline struct qcom_scm_response *qcom_scm_command_to_response(
-		const struct qcom_scm_command *cmd)
-{
-	return (void *)cmd + le32_to_cpu(cmd->resp_hdr_offset);
-}
-
-/**
- * qcom_scm_get_command_buffer() - Get a pointer to a command buffer
- * @cmd: command
- *
- * Returns a pointer to the command buffer of a command.
- */
-static inline void *qcom_scm_get_command_buffer(const struct qcom_scm_command *cmd)
-{
-	return (void *)cmd->buf;
-}
-
-/**
- * qcom_scm_get_response_buffer() - Get a pointer to a response buffer
- * @rsp: response
- *
- * Returns a pointer to a response buffer of a response.
- */
-static inline void *qcom_scm_get_response_buffer(const struct qcom_scm_response *rsp)
-{
-	return (void *)rsp + le32_to_cpu(rsp->buf_offset);
-}
-
-static int qcom_scm_remap_error(int err)
-{
-	pr_err("qcom_scm_call failed with error code %d\n", err);
-	switch (err) {
-	case QCOM_SCM_ERROR:
-		return -EIO;
-	case QCOM_SCM_EINVAL_ADDR:
-	case QCOM_SCM_EINVAL_ARG:
-		return -EINVAL;
-	case QCOM_SCM_EOPNOTSUPP:
-		return -EOPNOTSUPP;
-	case QCOM_SCM_ENOMEM:
-		return -ENOMEM;
-	}
-	return -EINVAL;
-}
-
-static u32 smc(u32 cmd_addr)
-{
-	int context_id;
-	register u32 r0 asm("r0") = 1;
-	register u32 r1 asm("r1") = (u32)&context_id;
-	register u32 r2 asm("r2") = cmd_addr;
-	do {
-		asm volatile(
-			__asmeq("%0", "r0")
-			__asmeq("%1", "r0")
-			__asmeq("%2", "r1")
-			__asmeq("%3", "r2")
-#ifdef REQUIRES_SEC
-			".arch_extension sec\n"
-#endif
-			"smc	#0	@ switch to secure world\n"
-			: "=r" (r0)
-			: "r" (r0), "r" (r1), "r" (r2)
-			: "r3");
-	} while (r0 == QCOM_SCM_INTERRUPTED);
-
-	return r0;
-}
-
-static int __qcom_scm_call(const struct qcom_scm_command *cmd)
-{
-	int ret;
-	u32 cmd_addr = virt_to_phys(cmd);
-
-	/*
-	 * Flush the command buffer so that the secure world sees
-	 * the correct data.
-	 */
-	__cpuc_flush_dcache_area((void *)cmd, cmd->len);
-	outer_flush_range(cmd_addr, cmd_addr + cmd->len);
-
-	ret = smc(cmd_addr);
-	if (ret < 0)
-		ret = qcom_scm_remap_error(ret);
-
-	return ret;
-}
-
-static void qcom_scm_inv_range(unsigned long start, unsigned long end)
-{
-	u32 cacheline_size, ctr;
-
-	asm volatile("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
-	cacheline_size = 4 << ((ctr >> 16) & 0xf);
-
-	start = round_down(start, cacheline_size);
-	end = round_up(end, cacheline_size);
-	outer_inv_range(start, end);
-	while (start < end) {
-		asm ("mcr p15, 0, %0, c7, c6, 1" : : "r" (start)
-		     : "memory");
-		start += cacheline_size;
-	}
-	dsb();
-	isb();
-}
-
-/**
- * qcom_scm_call() - Send an SCM command
- * @svc_id: service identifier
- * @cmd_id: command identifier
- * @cmd_buf: command buffer
- * @cmd_len: length of the command buffer
- * @resp_buf: response buffer
- * @resp_len: length of the response buffer
- *
- * Sends a command to the SCM and waits for the command to finish processing.
- *
- * A note on cache maintenance:
- * Note that any buffers that are expected to be accessed by the secure world
- * must be flushed before invoking qcom_scm_call and invalidated in the cache
- * immediately after qcom_scm_call returns. Cache maintenance on the command
- * and response buffers is taken care of by qcom_scm_call; however, callers are
- * responsible for any other cached buffers passed over to the secure world.
- */
-static int qcom_scm_call(u32 svc_id, u32 cmd_id, const void *cmd_buf,
-			size_t cmd_len, void *resp_buf, size_t resp_len)
-{
-	int ret;
-	struct qcom_scm_command *cmd;
-	struct qcom_scm_response *rsp;
-	unsigned long start, end;
-
-	cmd = alloc_qcom_scm_command(cmd_len, resp_len);
-	if (!cmd)
-		return -ENOMEM;
-
-	cmd->id = cpu_to_le32((svc_id << 10) | cmd_id);
-	if (cmd_buf)
-		memcpy(qcom_scm_get_command_buffer(cmd), cmd_buf, cmd_len);
-
-	mutex_lock(&qcom_scm_lock);
-	ret = __qcom_scm_call(cmd);
-	mutex_unlock(&qcom_scm_lock);
-	if (ret)
-		goto out;
-
-	rsp = qcom_scm_command_to_response(cmd);
-	start = (unsigned long)rsp;
-
-	do {
-		qcom_scm_inv_range(start, start + sizeof(*rsp));
-	} while (!rsp->is_complete);
-
-	end = (unsigned long)qcom_scm_get_response_buffer(rsp) + resp_len;
-	qcom_scm_inv_range(start, end);
-
-	if (resp_buf)
-		memcpy(resp_buf, qcom_scm_get_response_buffer(rsp), resp_len);
-out:
-	free_qcom_scm_command(cmd);
-	return ret;
-}
-
-#define SCM_CLASS_REGISTER	(0x2 << 8)
-#define SCM_MASK_IRQS		BIT(5)
-#define SCM_ATOMIC(svc, cmd, n) (((((svc) << 10)|((cmd) & 0x3ff)) << 12) | \
-				SCM_CLASS_REGISTER | \
-				SCM_MASK_IRQS | \
-				(n & 0xf))
-
-/**
- * qcom_scm_call_atomic1() - Send an atomic SCM command with one argument
- * @svc_id: service identifier
- * @cmd_id: command identifier
- * @arg1: first argument
- *
- * This shall only be used with commands that are guaranteed to be
- * uninterruptable, atomic and SMP safe.
- */
-static s32 qcom_scm_call_atomic1(u32 svc, u32 cmd, u32 arg1)
-{
-	int context_id;
-
-	register u32 r0 asm("r0") = SCM_ATOMIC(svc, cmd, 1);
-	register u32 r1 asm("r1") = (u32)&context_id;
-	register u32 r2 asm("r2") = arg1;
-
-	asm volatile(
-			__asmeq("%0", "r0")
-			__asmeq("%1", "r0")
-			__asmeq("%2", "r1")
-			__asmeq("%3", "r2")
-#ifdef REQUIRES_SEC
-			".arch_extension sec\n"
-#endif
-			"smc    #0      @ switch to secure world\n"
-			: "=r" (r0)
-			: "r" (r0), "r" (r1), "r" (r2)
-			: "r3");
-	return r0;
-}
-
-u32 qcom_scm_get_version(void)
-{
-	int context_id;
-	static u32 version = -1;
-	register u32 r0 asm("r0");
-	register u32 r1 asm("r1");
-
-	if (version != -1)
-		return version;
-
-	mutex_lock(&qcom_scm_lock);
-
-	r0 = 0x1 << 8;
-	r1 = (u32)&context_id;
-	do {
-		asm volatile(
-			__asmeq("%0", "r0")
-			__asmeq("%1", "r1")
-			__asmeq("%2", "r0")
-			__asmeq("%3", "r1")
-#ifdef REQUIRES_SEC
-			".arch_extension sec\n"
-#endif
-			"smc	#0	@ switch to secure world\n"
-			: "=r" (r0), "=r" (r1)
-			: "r" (r0), "r" (r1)
-			: "r2", "r3");
-	} while (r0 == QCOM_SCM_INTERRUPTED);
-
-	version = r1;
-	mutex_unlock(&qcom_scm_lock);
-
-	return version;
-}
-EXPORT_SYMBOL(qcom_scm_get_version);
-
-#define QCOM_SCM_SVC_BOOT			0x1
-#define QCOM_SCM_BOOT_ADDR			0x1
-/*
- * Set the cold/warm boot address for one of the CPU cores.
- */
-static int qcom_scm_set_boot_addr(u32 addr, int flags)
-{
-	struct {
-		__le32 flags;
-		__le32 addr;
-	} cmd;
-
-	cmd.addr = cpu_to_le32(addr);
-	cmd.flags = cpu_to_le32(flags);
-	return qcom_scm_call(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR,
-			&cmd, sizeof(cmd), NULL, 0);
-}
+#include "qcom_scm.h"
 
 /**
  * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus
@@ -414,26 +33,7 @@ static int qcom_scm_set_boot_addr(u32 addr, int flags)
  */
 int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus)
 {
-	int flags = 0;
-	int cpu;
-	int scm_cb_flags[] = {
-		QCOM_SCM_FLAG_COLDBOOT_CPU0,
-		QCOM_SCM_FLAG_COLDBOOT_CPU1,
-		QCOM_SCM_FLAG_COLDBOOT_CPU2,
-		QCOM_SCM_FLAG_COLDBOOT_CPU3,
-	};
-
-	if (!cpus || (cpus && cpumask_empty(cpus)))
-		return -EINVAL;
-
-	for_each_cpu(cpu, cpus) {
-		if (cpu < ARRAY_SIZE(scm_cb_flags))
-			flags |= scm_cb_flags[cpu];
-		else
-			set_cpu_present(cpu, false);
-	}
-
-	return qcom_scm_set_boot_addr(virt_to_phys(entry), flags);
+	return __qcom_scm_set_cold_boot_addr(entry, cpus);
 }
 EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
 
@@ -447,37 +47,10 @@ EXPORT_SYMBOL(qcom_scm_set_cold_boot_addr);
  */
 int qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus)
 {
-	int ret;
-	int flags = 0;
-	int cpu;
-
-	/*
-	 * Reassign only if we are switching from hotplug entry point
-	 * to cpuidle entry point or vice versa.
-	 */
-	for_each_cpu(cpu, cpus) {
-		if (entry == qcom_scm_wb[cpu].entry)
-			continue;
-		flags |= qcom_scm_wb[cpu].flag;
-	}
-
-	/* No change in entry function */
-	if (!flags)
-		return 0;
-
-	ret = qcom_scm_set_boot_addr(virt_to_phys(entry), flags);
-	if (!ret) {
-		for_each_cpu(cpu, cpus)
-			qcom_scm_wb[cpu].entry = entry;
-	}
-
-	return ret;
+	return __qcom_scm_set_warm_boot_addr(entry, cpus);
 }
 EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
 
-#define QCOM_SCM_CMD_TERMINATE_PC	0x2
-#define QCOM_SCM_FLUSH_FLAG_MASK	0x3
-
 /**
  * qcom_scm_cpu_power_down() - Power down the cpu
  * @flags - Flags to flush cache
@@ -488,7 +61,6 @@ EXPORT_SYMBOL(qcom_scm_set_warm_boot_addr);
  */
 void qcom_scm_cpu_power_down(u32 flags)
 {
-	qcom_scm_call_atomic1(QCOM_SCM_SVC_BOOT, QCOM_SCM_CMD_TERMINATE_PC,
-			flags & QCOM_SCM_FLUSH_FLAG_MASK);
+	__qcom_scm_cpu_power_down(flags);
 }
 EXPORT_SYMBOL(qcom_scm_cpu_power_down);
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
new file mode 100644
index 0000000..9fbede4
--- /dev/null
+++ b/drivers/firmware/qcom_scm.h
@@ -0,0 +1,29 @@
+/* Copyright (c) 2010-2014, 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 __QCOM_SCM_INT_H
+#define __QCOM_SCM_INT_H
+
+#define QCOM_SCM_SVC_BOOT		0x1
+#define QCOM_SCM_BOOT_ADDR		0x1
+#define QCOM_SCM_BOOT_ADDR_MC		0x11
+
+#define QCOM_SCM_FLAG_HLOS		0x01
+#define QCOM_SCM_FLAG_COLDBOOT_MC	0x02
+#define QCOM_SCM_FLAG_WARMBOOT_MC	0x04
+extern int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus);
+extern int __qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus);
+
+#define QCOM_SCM_CMD_TERMINATE_PC	0x2
+#define QCOM_SCM_FLUSH_FLAG_MASK	0x3
+#define QCOM_SCM_CMD_CORE_HOTPLUGGED	0x10
+extern void __qcom_scm_cpu_power_down(u32 flags);
+#endif
-- 
Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project