HIKEY OP-TEE切换UART运行状态

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已经实现了UART的安全状态的切换。打算基于此继续开发OPTEE_OS相应的各类驱动。
一.资源准备

OPTEE工程源码：OPTEE官网
注意：根据说明下载hikey_debian的代码版本。

二.实现方法

1.Hikey_Debian的代码版本带有helloworld的样例TA，可以修改为调用静态TA，当然也可以自行编写TA调用静态TA，调用方法前文讲述过了，不再累述。

2.下载OPTEE工程源码后，本身不能支持静态TA的编译和调用，需修改配置文件，修改方法参见：静态TA配置

3.修改/devel/optee/optee_os/core/arch/arm/plat-hikey/platform_config.h文件，经过与OP-TEE官方咨询，确定Hikey TZPC的基地址为0xF8002000，大小为0x878，修改内容如下：

...
...
#define CONSOLE_UART_BASE       0xF7113000
#else
#error Unknown console UART
#endif+/* TZPC */
+#define TZPC_BASE          0xF8002000
+#define TZPC_SIZE          0x878#define CONSOLE_BAUDRATE    115200
#define CONSOLE_UART_CLK_IN_HZ  19200000...
...

4.修改/devel/optee/optee_os/core/arch/arm/plat-hikey/main.c文件，默认的OP-TEE的可访问硬件地址中不包含TZPC的地址，需要自行添加进去，TZPC的地址位于安全世界下，则地址空间属性为MEM_AREA_IO_SEC，由于需要切换UART的运行状态，同样需要修改UART的地址权限也为SEC，也就是访问EL1下的地址，修改内容如下：


...
....cpu_suspend = pm_do_nothing,.cpu_resume = pm_do_nothing,.system_off = pm_do_nothing,.system_reset = pm_do_nothing,
};-register_phys_mem(MEM_AREA_IO_SEC, CONSOLE_UART_BASE, PL011_REG_SIZE);
+register_phys_mem(MEM_AREA_IO_SEC, CONSOLE_UART_BASE, PL011_REG_SIZE);+register_phys_mem(MEM_AREA_IO_SEC, TZPC_BASE, TZPC_SIZE);const struct thread_handlers *generic_boot_get_handlers(void)
{return &handlers;
}
...
...

4.在/devel/optee/optee_os/core/arch/arm/sta/目录下，新建sta_reg.c文件，作为静态TA文件，内容如下：

#include <compiler.h>
#include <stdio.h>
#include <trace.h>
#include <kernel/static_ta.h>
#include <string.h>
#include <string_ext.h>
#include <mm/tee_pager.h>
#include <mm/core_memprot.h>#include <drivers/pl011.h>#include <io.h> #define TA_NAME     "sta_reg.ta"#define STA_REG_UUID \{ 0xd96a5b40, 0x12c7, 0x21af, \{ 0x87, 0x94, 0x10, 0x02, 0xa5, 0xd5, 0xc6, 0x1b } }#define STA_READ_STATS      0
#define STA_WRITE_STATS     1#define CONSOLE_UART_BASE       0xF7113000/* flag register */
/* TZPC */ 
#define TZPC_BASE          0xF8002000
#define TZPC_SIZE          0x878#define SLAVE_PROTX_STATE    0x830#define SLAVE_PROTX_SET    0x834#define SLAVE_PROTX_CLEAN    0x838/*
#define set_sec_uart0     (1 << 26) UART0 设置安全状态
#define set_sec_uart1     (1 << 27) UART1 设置安全状态
#define set_sec_uart2     (1 << 28) UART2 设置安全状态
#define set_sec_uart3     (1 << 29) UART3 设置安全状态
#define set_sec_uart4     (1 << 30) UART4 设置安全状态*/static vaddr_t console_base(void)
{static void *va;if (cpu_mmu_enabled()) {if (!va)va = phys_to_virt(CONSOLE_UART_BASE, MEM_AREA_IO_SEC);return (vaddr_t)va;}return CONSOLE_UART_BASE;
}static vaddr_t tzpc_base(void)
{static void *va;if (cpu_mmu_enabled()) {if (!va)va = phys_to_virt(TZPC_BASE, MEM_AREA_IO_SEC);return (vaddr_t)va;}return TZPC_BASE;
}static TEE_Result read_regs(uint32_t type __unused, TEE_Param p[4] __unused)
{  EMSG("TZPC_UART_STATE: 0x%x\n",read32(tzpc_base()+SLAVE_PROTX_STATE));   return TEE_SUCCESS;
}static TEE_Result write_regs(uint32_t type __unused, TEE_Param p[4] __unused)
{ vaddr_t uart_base = console_base();int ch;MSG("TZPC_WRITE_UART:on the write");write32(0xFF000000, tzpc_base()+SLAVE_PROTX_SET);DMSG("TZPC_WRITE_UART:on the write finish");DMSG("welcome into the secure world!\n");DMSG("please input 'a' to back the normal world!\n");DMSG("TZPC_UART_STATE: 0x%x\n",read32(tzpc_base()+SLAVE_PROTX_STATE)); do{ch = pl011_getchar(uart_base);}while(ch != 97)write32(0xFFFFFFFF, tzpc_base()+SLAVE_PROTX_CLEAN);DMSG("have been back to the normal world!\n");return TEE_SUCCESS;
}/** Trusted Application Entry Points*/static TEE_Result create_ta(void)
{return TEE_SUCCESS;
}static void destroy_ta(void)
{
}static TEE_Result open_session(uint32_t ptype __unused,TEE_Param params[4] __unused,void **ppsess __unused)
{return TEE_SUCCESS;
}static void close_session(void *psess __unused)
{
}static TEE_Result invoke_command(void *psess __unused,uint32_t cmd, uint32_t ptypes,TEE_Param params[4])
{switch (cmd) {case STA_READ_STATS:return read_regs(ptypes, params);case STA_WRITE_STATS:return write_regs(ptypes, params);default:break;}return TEE_ERROR_BAD_PARAMETERS;
}static_ta_register(.uuid = STA_REG_UUID, .name = TA_NAME,.create_entry_point = create_ta,.destroy_entry_point = destroy_ta,.open_session_entry_point = open_session,.close_session_entry_point = close_session,.invoke_command_entry_point = invoke_command);