[PATCH v2 1/4] soc: Amlogic: Add secure monitor driver

Carlo Caione
2016-05-18T14:56:19Z

Introduce a driver to provide calls into secure monitor mode.

In the Amlogic SoCs these calls are used for multiple reasons: access to
NVMEM, set USB boot, enable JTAG, etc...

Signed-off-by: Carlo Caione <carlo-6IF/jdPJHihWk0Htik3J/w@public.gmane.org>
---
drivers/soc/Kconfig | 1 +
drivers/soc/Makefile | 1 +
drivers/soc/meson/Kconfig | 8 ++
drivers/soc/meson/Makefile | 1 +
drivers/soc/meson/meson_sm.c | 155 +++++++++++++++++++++++++++++++++++++
include/linux/soc/meson/meson_sm.h | 22 ++++++
6 files changed, 188 insertions(+)
create mode 100644 drivers/soc/meson/Kconfig
create mode 100644 drivers/soc/meson/Makefile
create mode 100644 drivers/soc/meson/meson_sm.c
create mode 100644 include/linux/soc/meson/meson_sm.h

diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index cb58ef0..7e70b52 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -4,6 +4,7 @@ source "drivers/soc/bcm/Kconfig"
source "drivers/soc/brcmstb/Kconfig"
source "drivers/soc/fsl/qe/Kconfig"
source "drivers/soc/mediatek/Kconfig"
+source "drivers/soc/meson/Kconfig"
source "drivers/soc/qcom/Kconfig"
source "drivers/soc/rockchip/Kconfig"
source "drivers/soc/samsung/Kconfig"
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 5ade713..9024d2b 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_ARCH_DOVE) += dove/
obj-$(CONFIG_MACH_DOVE) += dove/
obj-y += fsl/
obj-$(CONFIG_ARCH_MEDIATEK) += mediatek/
+obj-$(CONFIG_ARCH_MESON) += meson/
obj-$(CONFIG_ARCH_QCOM) += qcom/
obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
obj-$(CONFIG_SOC_SAMSUNG) += samsung/
diff --git a/drivers/soc/meson/Kconfig b/drivers/soc/meson/Kconfig
new file mode 100644
index 0000000..fff11a3
--- /dev/null
+++ b/drivers/soc/meson/Kconfig
@@ -0,0 +1,8 @@
+#
+# Amlogic Secure Monitor driver
+#
+config MESON_SM
+ bool
+ default ARCH_MESON
+ help
+ Say y here to enable the Amlogic secure monitor driver
diff --git a/drivers/soc/meson/Makefile b/drivers/soc/meson/Makefile
new file mode 100644
index 0000000..9ab3884
--- /dev/null
+++ b/drivers/soc/meson/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_MESON_SM) += meson_sm.o
diff --git a/drivers/soc/meson/meson_sm.c b/drivers/soc/meson/meson_sm.c
new file mode 100644
index 0000000..16f7e32
--- /dev/null
+++ b/drivers/soc/meson/meson_sm.c
@@ -0,0 +1,155 @@
+/*
+ * Amlogic Secure Monitor driver
+ *
+ * Copyright (C) 2016 Endless Mobile, Inc.
+ * Author: Carlo Caione <carlo-6IF/jdPJHihWk0Htik3J/w@public.gmane.org>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdarg.h>
+#include <asm/cacheflush.h>
+#include <asm/compiler.h>
+#include <linux/arm-smccc.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/smp.h>
+
+#include <linux/soc/meson/meson_sm.h>
+
+#define SM_MEM_SIZE 0x1000
+
+/*
+ * To read from / write to the secure monitor we use two bounce buffers. The
+ * physical addresses of the two buffers are obtained by querying the secure
+ * monitor itself.
+ */
+
+static u32 sm_phy_in_base;
+static u32 sm_phy_out_base;
+
+static void __iomem *sm_sharemem_in_base;
+static void __iomem *sm_sharemem_out_base;
+
+struct meson_sm_data {
+ u32 cmd;
+ u32 arg0;
+ u32 arg1;
+ u32 arg2;
+ u32 arg3;
+ u32 arg4;
+ u32 ret;
+};
+
+static void __meson_sm_call(void *info)
+{
+ struct meson_sm_data *data = info;
+ struct arm_smccc_res res;
+
+ arm_smccc_smc(data->cmd,
+ data->arg0, data->arg1, data->arg2,
+ data->arg3, data->arg4, 0, 0, &res);
+ data->ret = res.a0;
+}
+
+u32 meson_sm_call(u32 cmd, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4)
+{
+ struct meson_sm_data data;
+
+ data.cmd = cmd;
+ data.arg0 = arg0;
+ data.arg1 = arg1;
+ data.arg2 = arg2;
+ data.arg3 = arg3;
+ data.arg4 = arg4;
+ data.ret = 0;
+
+ __meson_sm_call(&data);
+
+ return data.ret;
+}
+
+u32 meson_sm_call_read(void *buffer, u32 cmd, u32 arg0, u32 arg1,
+ u32 arg2, u32 arg3, u32 arg4)
+{
+ u32 size;
+
+ size = meson_sm_call(cmd, arg0, arg1, arg2, arg3, arg4);
+
+ if (!size || size > SM_MEM_SIZE)
+ return -EINVAL;
+
+ memcpy(buffer, sm_sharemem_out_base, size);
+ return size;
+}
+
+u32 meson_sm_call_write(void *buffer, unsigned int b_size, u32 cmd, u32 arg0,
+ u32 arg1, u32 arg2, u32 arg3, u32 arg4)
+{
+ u32 size;
+
+ if (b_size > SM_MEM_SIZE)
+ return -EINVAL;
+
+ memcpy(sm_sharemem_in_base, buffer, b_size);
+
+ size = meson_sm_call(cmd, arg0, arg1, arg2, arg3, arg4);
+
+ if (!size)
+ return -EINVAL;
+
+ return size;
+}
+
+static int meson_sm_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ int cmd_in, cmd_out;
+
+ if (of_property_read_u32(np, "amlogic,sm_cmd_input_base", &cmd_in))
+ return -EINVAL;
+
+ if (of_property_read_u32(np, "amlogic,sm_cmd_output_base", &cmd_out))
+ return -EINVAL;
+
+ sm_phy_in_base = meson_sm_call(cmd_in, 0, 0, 0, 0, 0);
+ sm_sharemem_in_base = ioremap_cache(sm_phy_in_base, SM_MEM_SIZE);
+ if (!sm_sharemem_in_base)
+ return -EINVAL;
+
+ sm_phy_out_base = meson_sm_call(cmd_out, 0, 0, 0, 0, 0);
+ sm_sharemem_out_base = ioremap_cache(sm_phy_out_base, SM_MEM_SIZE);
+ if (!sm_sharemem_out_base) {
+ iounmap(sm_sharemem_in_base);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id meson_sm_ids[] = {
+ { .compatible = "amlogic,meson-sm" },
+ { /* sentinel */},
+};
+MODULE_DEVICE_TABLE(of, meson_sm_ids);
+
+static struct platform_driver meson_sm_platform_driver = {
+ .probe = meson_sm_probe,
+ .driver = {
+ .name = "secmon",
+ .of_match_table = meson_sm_ids,
+ },
+};
+module_platform_driver(meson_sm_platform_driver);
+
+MODULE_AUTHOR("Carlo Caione <carlo-6IF/jdPJHihWk0Htik3J/w@public.gmane.org>");
+MODULE_DESCRIPTION("Amlogic secure monitor driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/soc/meson/meson_sm.h b/include/linux/soc/meson/meson_sm.h
new file mode 100644
index 0000000..6ff8317
--- /dev/null
+++ b/include/linux/soc/meson/meson_sm.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2016 Endless Mobile, Inc.
+ * Author: Carlo Caione <carlo-6IF/jdPJHihWk0Htik3J/w@public.gmane.org>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _MESON_SM_H_
+#define _MESON_SM_H_
+
+u32 meson_sm_call(u32 cmd, u32 arg0, u32 arg1, u32 arg2, u32 arg3, u32 arg4);
+u32 meson_sm_call_read(void *buffer, u32 cmd, u32 arg0, u32 arg1, u32 arg2,
+ u32 arg3, u32 arg4);
+u32 meson_sm_call_write(void *buffer, unsigned int b_size, u32 cmd, u32 arg0,
+ u32 arg1, u32 arg2, u32 arg3, u32 arg4);
+
+#endif /* _MESON_SM_H_ */