XILINX GPIO驱动分析

High Level – level 1 hardware driver api

Low Level – level 0 hardware driver api

XGPIO.H

#include "xil_types.h"

#include "xil_assert.h"

#include "xstatus.h"

#include "xgpio_l.h"

Define:

XGpio_CfgInitialize

XGpio_SetDataDirection

XGPIO.C

#include "xgpio.h"

#include "xstatus.h"

Implement:

XGpio_CfgInitialize

XGpio_SetDataDirection

<==上面API：

#include "xgpio_l.h" (xgpio low level)

XGPIO_L.H:

#include "xil_types.h"

#include "xil_assert.h"

#include "xil_io.h"

#define XGPIO_DATA_OFFSET 0x0 /**< Data register for 1st channel */

#define XGPIO_TRI_OFFSET 0x1 /**< I/O direction reg for 1st channel */

#define XGPIO_DATA2_OFFSET 0x2 /**< Data register for 2nd channel */

#define XGPIO_TRI2_OFFSET 0x3 /**< I/O direction reg for 2nd channel */

#define XGPIO_GIE_OFFSET 0x47 /**< Global interrupt enable register */

#define XGPIO_ISR_OFFSET 0x48 /**< Interrupt status register */

#define XGPIO_IER_OFFSET 0x4A /**< Interrupt enable register */

#define XGpio_ReadReg Xil_In32 ==> (xil_io.c)

XGPIO_L.C文件不存在，因为LOW LEVEL的驱动全是MACRO写的，不需要C文件实现。

< == 上面API：

#include "xil_io.h"

XIL_IO.H：

#include "xil_types.h"

#include "xpseudo_asm.h"

#include "xil_printf.h"

DEFINE:

u8 Xil_In8(u32 Addr);

u16 Xil_In16(u32 Addr);

u32 Xil_In32(u32 Addr);

XIL_IO.C

#include "xil_io.h"

#include "xil_types.h"

#include "xil_assert.h"

#include "xpseudo_asm.h"

#include "xreg_cortexa9.h"

Implement:

u8 Xil_In8(u32 Addr);

u16 Xil_In16(u32 Addr);

u32 Xil_In32(u32 Addr);

<= =上层API：

#include "xpseudo_asm.h"

#include "xreg_cortexa9.h"

XPSEUDO_ASM.H 没有C文件

#include "xreg_cortexa9.h"

#include "xpseudo_asm_gcc.h"

XREG_CORTEXA9.H 没有C文件

/* GPRs */

#define XREG_GPR0 r0

#define XREG_GPR1 r1

#define XREG_GPR2 r2

#define XREG_GPR14 r14

#define XREG_GPR15 r15

#define XREG_CPSR cpsr

XPSEUDO_ASM_GCC.H：没有C文件

/* pseudo assembler instructions */

#define mfcpsr() ({unsigned int rval; \

__asm__ __volatile__(\

"mrs %0, cpsr\n"\

: "=r" (rval)\

);\

rval;\

})

/* Memory Operations */

#define ldr(adr) ({unsigned long rval; \

__asm__ __volatile__(\

"ldr %0,[%1]"\

: "=r" (rval) : "r" (adr)\

);\

rval;\

})

下图是各个文件与其对应的功能图：

下图是GPIO模块驱动API的层次结构图：