wince 2440串口驱动PDD分析（作者：wogoyixikexie@gliet）

                   wince 2440串口驱动PDD分析（作者：wogoyixikexie@gliet）

    经过前面的MDD分析可知，wince串口的接口函数com_init，Com_Open等函数是放在MDD中的，应用程序直接和MDD打交道，然后把需求传到中间层（介于MDD和PDD之间）中间层再调用PDD的函数（和硬件相关的函数）来实现。PDD是硬件相关的操作，如果需要增加串口个数或者外扩串口芯片都需要在这个PDD中实现。Come on！

    在执行com_init函数的时候会间接调用到

1. //根据串口编号创建对象，如果要增加串口个数要修改这个函数，增加case即可。
2. CSerialPDD * CreateSerialObject(LPTSTR lpActivePath, PVOID pMdd,PHWOBJ pHwObj, DWORD DeviceArrayIndex)
3. {
4.     CSerialPDD * pSerialPDD = NULL;
5.     switch (DeviceArrayIndex) {
6.       case 0://和物理串口对应
7.         pSerialPDD = new CPdd2440Serial1(lpActivePath,pMdd, pHwObj);//在PDD实现
8.         break;
9.       case 1:
10.         pSerialPDD = new CPdd2440Serial2(lpActivePath,pMdd, pHwObj);
11.         break;
12.     }
13.     if (pSerialPDD && !pSerialPDD->Init()) {
14.         delete pSerialPDD;
15.         pSerialPDD = NULL;
16.     }    
18.     return pSerialPDD;
19. }

____________________________________________________________________________________________

if (pSerialPDD && !pSerialPDD->Init()) ——读取注册表串口部分

 

1. BOOL CPdd2440Uart::Init()
2. {
3.     if ( CSerialPDD::Init() && IsKeyOpened() && m_XmitFlushDone!=NULL) { 
4.         // IST Setup .--------Get IRQ forom regedit
5.         DDKISRINFO ddi;
6.         if (GetIsrInfo(&ddi)!=ERROR_SUCCESS) {
7.             return FALSE;
8.         }
9.         m_dwSysIntr = ddi.dwSysintr;
10.         if (m_dwSysIntr !=  MAXDWORD && m_dwSysIntr!=0 ) 
11.             m_hISTEvent= CreateEvent(0,FALSE,FALSE,NULL);
12.         
13.         if (m_hISTEvent!=NULL)
14.             InterruptInitialize(m_dwSysIntr,m_hISTEvent,0,0);
15.         else
16.             return FALSE;
17.         
18.         // Get Device Index.
19.         if (!GetRegValue(PC_REG_DEVINDEX_VAL_NAME, (PBYTE)&m_dwDevIndex, PC_REG_DEVINDEX_VAL_LEN)) {
20.             m_dwDevIndex = 0;
21.         }
22.         if (!GetRegValue(PC_REG_SERIALWATERMARK_VAL_NAME,(PBYTE)&m_dwWaterMark,sizeof(DWORD))) {
23.             m_dwWaterMark = 8;
24.         }
25.         if (!GetRegValue(PC_REG_2440UART_INTBIT_VAL_NAME,(PBYTE)&m_dwIntShift,sizeof(DWORD))) {
26.             RETAILMSG(1,(TEXT("Registery does not have %s set. Drivers fail!!!/r/n"),PC_REG_2440UART_INTBIT_VAL_NAME));
27.             m_dwIntShift =0;
28.             return FALSE;
29.         }
30.         if (!GetRegValue(PC_REG_2440UART_IST_TIMEOUTS_VAL_NAME,(PBYTE)&m_dwISTTimeout, PC_REG_2440UART_IST_TIMEOUTS_VAL_LEN)) {
31.             m_dwISTTimeout = INFINITE;
32.         }
33.         if (!MapHardware() || !CreateHardwareAccess()) {
34.             return FALSE;
35.         }
36.         
37.         return TRUE;        
38.     }
39.     return FALSE;
40. }

现在来看看它里面分配的对象，三星的BSP刚好只有两个串口驱动，另外一个做了调试串口。

2. // CPdd2440Serial1 is only use for UART 0 which 
3. // RTS & CTS is use GPH0 GPH1
4. // DTR & DSR is USE GPD0 GPD1
5. class CPdd2440Serial1 : public CPdd2440Uart {
6. public:
7.     CPdd2440Serial1(LPTSTR lpActivePath, PVOID pMdd, PHWOBJ pHwObj)
8.         : CPdd2440Uart(lpActivePath, pMdd, pHwObj)
9.         {
10.         m_pIOPregs = NULL;
11.         m_fIsDSRSet = FALSE;
12.     }
13.     ~CPdd2440Serial1() {
14.         if (m_pIOPregs!=NULL)
15.             MmUnmapIoSpace((PVOID)m_pIOPregs,0);
16.     }
17.     virtual BOOL Init() {
18.         PHYSICAL_ADDRESS    ioPhysicalBase = { S3C2440A_BASE_REG_PA_IOPORT, 0};
19.         ULONG               inIoSpace = 0;
20.         if (TranslateBusAddr(m_hParent,Internal,0, ioPhysicalBase,&inIoSpace,&ioPhysicalBase)) {
21.             // Map it if it is Memeory Mapped IO.
22.             m_pIOPregs = (S3C2440A_IOPORT_REG *)MmMapIoSpace(ioPhysicalBase, sizeof(S3C2440A_IOPORT_REG),FALSE);
23.         }
24.         if (m_pIOPregs) {
25.             DDKISRINFO ddi;
26.             if (GetIsrInfo(&ddi)== ERROR_SUCCESS && 
27.                     KernelIoControl(IOCTL_HAL_REQUEST_SYSINTR, &ddi.dwIrq, sizeof(UINT32), &ddi.dwSysintr, sizeof(UINT32), NULL))
28.             {   
29.                 RegSetValueEx(DEVLOAD_SYSINTR_VALNAME,REG_DWORD,(PBYTE)&ddi.dwSysintr, sizeof(UINT32));
30.             }
31.             else
32.                 return FALSE;
33.             m_pDTRPort = (volatile ULONG *)&(m_pIOPregs->GPDDAT);
34.             m_pDSRPort = (volatile ULONG *)&(m_pIOPregs->GPDDAT);
35.             m_dwDTRPortNum = 0;
36.             m_dwDSRPortNum = 1;
38.             m_pIOPregs->GPHCON &= ~(0x3<<0 | 0x3<<2 | 0x3<<4 | 0x3<<6 );//tx,rx,rts,cts
39.             m_pIOPregs->GPHCON |=  (0x2<<0 | 0x2<<2 | 0x2<<4 | 0x2<<6 ); 
40.             m_pIOPregs->GPHCON |= (0x2<<0 | 0x2<<2);
41.             m_pIOPregs->GPHUP  |= 0xf;
43.             m_pIOPregs->GPDCON &= ~(0x3<<0 | 0x3<<2);//dtr,dsr
44.             m_pIOPregs->GPDCON |= (0x1<<0 | 0x0<<2);
45.             m_pIOPregs->GPDUP  |= 0x3;
47.             return CPdd2440Uart::Init();
48.         }
49.         return FALSE;
50.     };
51.     virtual void    SetDefaultConfiguration() {
52.         CPdd2440Uart::SetDefaultConfiguration();
53.     }
54.     virtual BOOL    InitModem(BOOL bInit) {
55.         SetDTR(bInit);
56.         return CPdd2440Uart::InitModem(bInit);
57.     }
58.     virtual ULONG   GetModemStatus() {
59.         ULONG ulReturn = CPdd2440Uart::GetModemStatus();
60.         ULONG ulEvent = 0;
61.         m_HardwareLock.Lock();
62.         BOOL fIsDSRSet = (((*m_pDSRPort) & (1<<m_dwDSRPortNum))==0);
63.         if (fIsDSRSet != m_fIsDSRSet) {
64.             ulEvent |= EV_DSR | EV_RLSD;
65.         }
66.         ulReturn |= (fIsDSRSet?(MS_DSR_ON|MS_RLSD_ON):0);
67.         m_fIsDSRSet = fIsDSRSet;
68.         m_HardwareLock.Unlock();
69.         if (ulEvent!=0)
70.             EventCallback(ulEvent,ulReturn);
71.         return ulReturn;
72.     }
73.     virtual void    SetDTR(BOOL bSet) {
74.         if (bSet)
75.             *m_pDTRPort &= ~(1<<m_dwDTRPortNum);
76.         else
77.             *m_pDTRPort |= (1<<m_dwDTRPortNum);
78.     };
79. private:
80.     volatile S3C2440A_IOPORT_REG * m_pIOPregs; 
81.     volatile ULONG *    m_pDTRPort;
82.     DWORD               m_dwDTRPortNum;
83.     volatile ULONG *    m_pDSRPort;
84.     DWORD               m_dwDSRPortNum;
85.     BOOL                m_fIsDSRSet;
86. };
87. —————————————————————————————
90. // CPdd2440Serial2 is only use for UART 2 which 
91. // nIrDATXDEN use GPB1
92. class CPdd2440Serial2 : public CPdd2440Uart {
93. public:
94.     CPdd2440Serial2(LPTSTR lpActivePath, PVOID pMdd, PHWOBJ pHwObj)
95.         : CPdd2440Uart(lpActivePath, pMdd, pHwObj)
96.         {
97.         m_pIOPregs = NULL;
98.     }
99.     ~CPdd2440Serial2() {
100.         if (m_pIOPregs!=NULL)
101.             MmUnmapIoSpace((PVOID)m_pIOPregs,0);
102.     }
103.     virtual BOOL Init() {
104.         PHYSICAL_ADDRESS    ioPhysicalBase = { S3C2440A_BASE_REG_PA_IOPORT, 0};
105.         ULONG               inIoSpace = 0;
106.         if (TranslateBusAddr(m_hParent,Internal,0, ioPhysicalBase,&inIoSpace,&ioPhysicalBase)) {
107.             // Map it if it is Memeory Mapped IO.
108.             m_pIOPregs =(S3C2440A_IOPORT_REG *) MmMapIoSpace(ioPhysicalBase, sizeof(S3C2440A_IOPORT_REG),FALSE);
109.         }
110.         if (m_pIOPregs) {
111.             DDKISRINFO ddi;
112.             if (GetIsrInfo(&ddi)== ERROR_SUCCESS && 
113.                     KernelIoControl(IOCTL_HAL_REQUEST_SYSINTR, &ddi.dwIrq, sizeof(UINT32), &ddi.dwSysintr, sizeof(UINT32), NULL))
114.             {   
115.                 RegSetValueEx(DEVLOAD_SYSINTR_VALNAME,REG_DWORD,(PBYTE)&ddi.dwSysintr, sizeof(UINT32));
116.             }
117.             else
118.                 return FALSE;
120.             m_pIOPregs->GPHCON &= ~(0x3<<12 | 0x3<<14); // clear rxd2 txd2
121.             m_pIOPregs->GPHCON |= (0x2<<12 | 0x2<<14); //enabled rxd2 txd2
122.             m_pIOPregs->GPHUP |= 0xc0;//disable pull up
123.         
124.             //m_pIOPregs->GPBCON &= ~(0x3<<2);  //GPB1 -> nIrDATXDEN
125.             //m_pIOPregs->GPBCON |=  (0x1<<2); 
126.             //m_pIOPregs->GPBUP  |=  (0x1<<1);
127.             //m_pIOPregs->GPBDAT &= ~(0x1<<1);
129.             return CPdd2440Uart::Init();
130.         }
131.         return FALSE;
132.     };
133.     virtual void    SetDefaultConfiguration() {
134.         CPdd2440Uart::SetDefaultConfiguration();
135.     }
136.     virtual ULONG   GetModemStatus() {
137.         return (CPdd2440Uart::GetModemStatus() | MS_CTS_ON);
138.     }
139.     virtual void    Rx_Pause(BOOL bSet) {
140.         if(bSet)
141.             m_pIOPregs->GPHCON = (m_pIOPregs->GPHCON & ~(0x3<<14)) | 0x0<<14;
142.         else    
143.             m_pIOPregs->GPHCON = (m_pIOPregs->GPHCON & ~(0x3<<14)) | 0x2<<14;
144.     }
146.     volatile S3C2440A_IOPORT_REG * m_pIOPregs; 
147. };

 

——鉴于我的C++水平，我就先沉默了。看来要花点时间学习一下。

1. // I must learn well C++ 
2. //前面刚有人回帖说做驱动工程师不用C++，现在郁闷了吧。
3. //对于这个KernelIoControl要有新的认识才行
4. CReg2440Uart::CReg2440Uart(PULONG pRegAddr)
5. :   m_pReg(pRegAddr)
6. {
7.     m_fIsBackedUp = FALSE;
8.     PROCESSOR_INFO procInfo;
9.     DWORD dwBytesReturned;
10.     //IOCTL_PROCESSOR_INFORMATION? Why do use it?
11.     if (!KernelIoControl(IOCTL_PROCESSOR_INFORMATION, NULL, 0, &procInfo, sizeof(PROCESSOR_INFO), &dwBytesReturned))
12.     {
13.         m_s3c2440_pclk = DEFAULT_S3C2440A_PCLK;
14.         RETAILMSG(TRUE, (TEXT("WARNING: CReg2440Uart::CReg2440Uart failed to obtain processor frequency - using default value (%d)./r/n"), m_s3c2440_pclk)); 
15.     }
16.     else
17.     {
18.         m_s3c2440_pclk = procInfo.dwClockSpeed;
19.         RETAILMSG(TRUE, (TEXT("INFO: CReg2440Uart::CReg2440Uart using processor frequency reported by the OAL (%d)./r/n"), m_s3c2440_pclk)); 
20.     }
22. }

现在来看看IOCTL_PROCESSOR_INFORMATION这东西到底是做什么的，在BSP下oal_ioctl_tab.h有

{ IOCTL_PROCESSOR_INFORMATION,              0,  OALIoCtlProcessorInfo       },
也就是说通过KernelIoControl执行了OALIoCtlProcessorInfo  这个函数。在别的地方也发现了IOCTL_PROCESSOR_INFORMATION

smdk2440_ARMV4I/cesysgen/oak/inc/pkfuncs.h(327)

#define IOCTL_PROCESSOR_INFORMATION   CTL_CODE(FILE_DEVICE_HAL, 25, METHOD_BUFFERED, FILE_ANY_ACCESS)

现在来看看这个CTL_CODE是什么东西，看PB帮助文档如下：

This macro creates a unique system I/O control code (IOCTL).

#define CTL_CODE(DeviceType, Function, Method, Access) (
((DeviceType) << 16) | ((Access) << 14) | ((Function) << 2) | (Method)
)

Parameters
    
    
    
    

     
     
     
     
 
      DeviceType 
     
     
     
     
     

       Defines the type of device for the given IOCTL. 
      
This parameter can be no bigger than a WORD value. 
 
      
The values used by Microsoft are in the range 0-32767; the values 32768-65535 are reserved for use by OEMs and IHVs. 
 
     
     
     
     
     
 
      
The following device types are specific to Windows CE: 
 
      
 
       
FILE_DEVICE_HAL 
 
       
FILE_DEVICE_CONSOLE 
 
       
FILE_DEVICE_PSL 
 
       
FILE_DEVICE_SERVICE 
 
      
 
     
     
     
     
     
 
      
...更多信息请看PB帮助ms-help://MS.WindowsCE.500/wcehardware5/html/wce50lrfCTLCODE.htm
 
     
    
    
    
    

 

现在来看看OALIoCtlProcessorInfo 这个函数是怎么实现的。

C:/WINCE500/PLATFORM/COMMON/SRC/COMMON/IOCTL/procinfo.c

 

 

 

1. //------------------------------------------------------------------------------
2. //
3. //  Function:  OALIoCtlProcessorInformation
4. //
5. //  Implements the IOCTL_PROCESSOR_INFORMATION handler.
6. //
7. BOOL OALIoCtlProcessorInfo(
8.     UINT32 code, VOID *pInpBuffer, UINT32 inpSize, VOID *pOutBuffer, 
9.     UINT32 outSize, UINT32 *pOutSize
10. ) {
11.     BOOL rc = FALSE;
12.     PROCESSOR_INFO *pInfo = (PROCESSOR_INFO*)pOutBuffer;
13.     UINT32 length1, length2, length3;
15.     OALMSG(OAL_FUNC, (L"+OALIoCtlProcessorInfo(...)/r/n"));
17.     // Set required/returned size if pointer isn't NULL
18.     if (pOutSize != NULL) *pOutSize = sizeof(PROCESSOR_INFO);
19.     
20.     // Validate inputs
21.     if (pOutBuffer == NULL || outSize < sizeof(PROCESSOR_INFO)) {
22.         NKSetLastError(ERROR_INSUFFICIENT_BUFFER);
23.         OALMSG(OAL_WARN, (
24.             L"WARN: OALIoCtlProcessorInfo: Buffer too small/r/n"
25.         ));
26.         goto cleanUp;
27.     }
29.     // Verify OAL lengths
30.     length1 = (NKwcslen(g_oalIoCtlProcessorCore) + 1) * sizeof(WCHAR);
31.     if (length1 > sizeof(pInfo->szProcessCore)) {
32.         OALMSG(OAL_ERROR, (
33.             L"ERROR:OALIoCtlProcessorInfo: Core value too big/r/n"
34.         ));
35.         goto cleanUp;
36.     }
38.     length2 = (NKwcslen(g_oalIoCtlProcessorName) + 1) * sizeof(WCHAR);
39.     if (length2 > sizeof(pInfo->szProcessorName)) {
40.         OALMSG(OAL_ERROR, (
41.             L"ERROR:OALIoCtlProcessorInfo: Name value too big/r/n"
42.         ));
43.         goto cleanUp;
44.     }
46.     length3 = (NKwcslen(g_oalIoCtlProcessorVendor) + 1) * sizeof(WCHAR);
47.     if (length3 > sizeof(pInfo->szVendor)) {
48.         OALMSG(OAL_ERROR, (
49.             L"ERROR:OALIoCtlProcessorInfo: Vendor value too big/r/n"
50.         ));
51.         goto cleanUp;
52.     }
54.     // Copy in processor information    
55.     pInfo->wVersion = 1;
56.     memset(pInfo, 0, sizeof(PROCESSOR_INFO));
57.     memcpy(pInfo->szProcessCore, g_oalIoCtlProcessorCore, length1);
58.     memcpy(pInfo->szProcessorName, g_oalIoCtlProcessorName, length2);
59.     memcpy(pInfo->szVendor, g_oalIoCtlProcessorVendor, length3);
60.     pInfo->dwInstructionSet = g_oalIoCtlInstructionSet;
61.     pInfo->dwClockSpeed  = g_oalIoCtlClockSpeed;
63.     // Indicate success
64.     rc = TRUE;
66. cleanUp:
67.     OALMSG(OAL_FUNC, (L"-OALIoCtlProcessorInfo(rc = %d)/r/n", rc));
68.     return rc;
69. }
71. //---------------------------------？？？好复杂，看不懂。等下再看了。

——————————————————————————————————————————————————————

现在来看点实际点的东西吧。

——我发现这个串口物理中断转换成逻辑（系统）中断有点奇怪。

DDKISRINFO ddi;
            if (GetIsrInfo(&ddi)== ERROR_SUCCESS &&
                    KernelIoControl(IOCTL_HAL_REQUEST_SYSINTR, &ddi.dwIrq, sizeof(UINT32), &ddi.dwSysintr, sizeof(UINT32), NULL))
            {  
                RegSetValueEx(DEVLOAD_SYSINTR_VALNAME,REG_DWORD,(PBYTE)&ddi.dwSysintr, sizeof(UINT32));
            }

 

——————找到GetIsrInfo函数：C:/WINCE500/PUBLIC/COMMON/OAK/INC/cregedit.h(99)

 DWORD   GetIsrInfo( DDKISRINFO* pddi )
    {
        if( pddi && m_hDevKey )
        {
            pddi->cbSize = sizeof( DDKISRINFO );
            DWORD status = DDKReg_GetIsrInfo( m_hDevKey, pddi );
            return status;
        }
        else
        {
            return ERROR_INVALID_FUNCTION;
        }
    }

——由此可知最终还是通过DDKReg_GetIsrInfo来实现，继续跟踪。

哦，天啊，这个函数不开源的。

This function populates a DDKISRINFO structure with information from the registry. If you specify an interrupt service routine (ISR) DLL, you must also specify a handler entry point and an interrupt request (IRQ).

DWORD WINAPI DDKReg_GetIsrInfo(
  HKEY hk, 
  PDDKISRINFO pii
);

Parameters

hk

[in] Handle to a registry key.

pii

[out] Pointer to a DDKISRINFO structure.

Requirements

OS Versions: Windows CE .NET 4.0 and later.
Header: Ddkreg.h.
Link Library: Coredll.lib.—————————不开源的

上面的DDKISRINFO结构体

This structure contains interrupt service routine (ISR) information.

typedef struct _DDKISRINFO_tag {
  DWORD cbSize;
  DWORD dwIrq;
  DWORD dwSysintr;
  WCHAR szIsrDll[DEVDLL_LEN];
  WCHAR szIsrHandler[DEVENTRY_LEN];
} DDKISRINFO, *PDDKISRINFO;

Members

cbSize

Size of this structure.

dwIrq

Interrupt number. Use Irq in the registry or IRQ_UNSPECIFIED if there is no entry.

dwSysintr

Interrupt identifier. Use Sysintr in the registry or SYSINTR_NOP if there is no entry.

szIsrDll

Installable ISR DLL. Use IsrDll in the registry.

szIsrHandler

Installable ISR DLL entry point. Use IsrHandler in the registry.

Requirements

OS Versions: Windows CE .NET 4.0 and later.
Header: Ddkreg.h.

——————————————————————————————————————————————