reactos/drivers/dd/serial/serial.c

   1 /* $Id$
   2  *
   3  * Serial driver
   4  * Written by Jason Filby (jasonfilby@yahoo.com)
   5  * For ReactOS (www.reactos.com)
   6  *
   7  */
   8
   9 #include <ddk/ntddk.h>
  10 //#include <internal/mmhal.h>
  11 //#include "../../../ntoskrnl/include/internal/i386/io.h"
  12 //#include "../../../ntoskrnl/include/internal/io.h"
  13
  14 #define outb_p(a,p) WRITE_PORT_UCHAR((PUCHAR)a,p)
  15 #define outw_p(a,p) WRITE_PORT_USHORT((PUSHORT)a,p)
  16 #define inb_p(p)    READ_PORT_UCHAR((PUCHAR)p)
  17
  18 #define NDEBUG
  19 #include <debug.h>
  20
  21
  22 #define COM1    0x3F8
  23 #define COM2    0x2F8
  24 #define COM3    0x3E8
  25 #define COM4    0x2E8
  26
  27 #define UART_BAUDRATE   96      // 1200 BPS
  28 #define UART_LCRVAL     0x1b    // 0x1b for 8e1
  29 #define UARY_FCRVAL     0x7
  30
  31 int uart_detect(unsigned base)
  32 {
  33         // Returns 0 if no UART detected
  34
  35         outb_p(base+4, 0x10);
  36         if ((inb_p(base+6) & 0xf0)) return 0;
  37         return 1;
  38 };
  39
  40 int irq_setup(unsigned base)
  41 {
  42         // Returns -1 if not found -- otherwise returns interrupt level
  43
  44         char ier, mcr, imrm, imrs, maskm, masks, irqm, irqs;
  45
  46         __asm("cli");          // disable all CPU interrupts
  47         ier = inb_p(base+1);   // read IER
  48         outb_p(base+1,0);      // disable all UART ints
  49         while (!(inb_p(base+5)&0x20));  // wait for the THR to be empty
  50         mcr = inb_p(base+4);   // read MCR
  51         outb_p(base+4,0x0F);   // connect UART to irq line
  52         imrm = inb_p(0x21);    // read contents of master ICU mask register
  53         imrs = inb_p(0xA1);    // read contents of slave ICU mask register
  54         outb_p(0xA0,0x0A);     // next read access to 0xA0 reads out IRR
  55         outb_p(0x20,0x0A);     // next read access to 0x20 reads out IRR
  56         outb_p(base+1,2);      // let's generate interrupts...
  57         maskm = inb_p(0x20);   // this clears all bits except for the one
  58         masks = inb_p(0xA0);   // that corresponds to the int
  59         outb_p(base+1,0);      // drop the int line
  60         maskm &= ~inb_p(0x20); // this clears all bits except for the one
  61         masks &= ~inb_p(0xA0); // that corresponds to the int
  62         outb_p(base+1,2);      // and raise it again just to be sure...
  63         maskm &= inb_p(0x20);  // this clears all bits except for the one
  64         masks &= inb_p(0xA0);  // that corresponds to the int
  65         outb_p(0xA1,~masks);   // now let us unmask this interrupt only
  66         outb_p(0x21,~maskm);
  67         outb_p(0xA0,0x0C);     // enter polled mode
  68         outb_p(0x20,0x0C);     // that order is important with Pentium/PCI systems
  69         irqs = inb_p(0xA0);    // and accept the interrupt
  70         irqm = inb_p(0x20);
  71         inb_p(base+2);         // reset transmitter interrupt in UART
  72         outb_p(base+4,mcr);    // restore old value of MCR
  73         outb_p(base+1,ier);    // restore old value of IER
  74         if (masks) outb_p(0xA0,0x20);  // send an EOI to slave
  75         if (maskm) outb_p(0x20,0x20);  // send an EOI to master
  76         outb_p(0x21,imrm);     // restore old mask register contents
  77         outb_p(0xA1,imrs);
  78         __asm("sti");
  79         if (irqs&0x80)       // slave interrupt occured
  80           return (irqs&0x07)+8;
  81         if (irqm&0x80)       // master interrupt occured
  82           return irqm&0x07;
  83         return -1;
  84 };
  85
  86 void uart_init(unsigned uart_base)
  87 {
  88         // Initialize the UART
  89         outb_p(uart_base+3, 0x80);
  90         outw_p(uart_base, UART_BAUDRATE);
  91         outb_p(uart_base+3, UART_LCRVAL);
  92         outb_p(uart_base+4, 0);
  93 };
  94
  95 unsigned uart_getchar(unsigned uart_base)
  96 {
  97         unsigned x;
  98
  99         x=(inb_p(uart_base+5) & 0x9f) << 8;
 100         if(x & 0x100) x|=((unsigned)inb_p(uart_base)) & 0xff;
 101         return x;
 102 };
 103
 104 void InitializeSerial(void)
 105 {
 106         unsigned comports[4] = { COM1, COM2, COM3, COM4 };
 107         char *comname[4] = { "COM1", "COM2", "COM3", "COM4" };
 108         int i, irq_level;
 109
 110         for (i=0; i<4; i++)
 111         {
 112                 if(uart_detect(comports[i])==0)
 113                 {
 114                           DbgPrint("%s not detected\n", comname[i]);
 115                 } else {
 116                           uart_init(comports[i]);
 117                           irq_level=irq_setup(comports[i]);
 118                           if(irq_level==-1)
 119                           {
 120                                     DbgPrint("Warning: IRQ not detected!\n");
 121                           } else {
 122                                     DbgPrint("%s hooked to interrupt level %d\n", comname[i], irq_level);
 123                           };
 124                 };
 125         };
 126 };
 127
 128 // For testing purposes
 129 void testserial(void)
 130 {
 131         int i=0;
 132         char testc;
 133
 134         union {
 135           unsigned val;
 136           char character;
 137         } x;
 138
 139         DbgPrint("Testing serial input...\n");
 140
 141         while(i==0) {
 142           x.val=uart_getchar(COM1);
 143 //    if(!x.val) continue;
 144 //    if(x.val & 0x100)
 145
 146                 testc=inb_p(COM1);
 147
 148 //    DbgPrint("(%x-%c)  %c\n", x.val, x.character, testc);
 149         };
 150 };
 151
 152 NTSTATUS STDCALL
 153 DriverEntry(PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath)
 154 {
 155         DbgPrint("Serial Driver 0.0.2\n");
 156 //        InitializeSerial();
 157 //        testserial();
 158         return(STATUS_SUCCESS);
 159 };
 160